Indole alkaloids isolated from the Nicotiana tabacum-derived Aspergillus fumigatus 0338 as potential inhibitors for tobacco powdery mildew and their mode of actions.

To explore active natural products against tobacco powdery mildew caused by Golovinomyces cichoracearum, an extract from the fermentation of endophytic Aspergillus fumigatus 0338 was investigated. The mechanisms of action for active compounds were also studied in detail. As a result, 14 indole alkaloid derivatives were isolated, with seven being newly discovered (1-7) and the remaining seven previously described (8-14). Notably, compounds 1-3 are rare linearly fused 6/6/5 tricyclic prenylated indole alkaloids, with asperversiamide J being the only known natural product of this kind. The isopentenyl substitutions at the 5-position in compounds 4 and 5 are also rare, with only compounds 1-(5-prenyl-1H-indol-3-yl)-propan-2-one (8) and 1-(6-methoxy-5-prenyl-1H-indol3-yl)-propan-2-one currently available. In addition, compounds 6 and 7 are new framework indole alkaloid derivatives bearing a 6-methyl-1,7-dihydro-2H-azepin-2-one ring. The purified compounds were evaluated for their activity against G. cichoracearum, and the results revealed that compounds 7 and 9 demonstrated obvious anti-G. cichoracearum activities with an inhibition rate of 82.6% and 85.2%, respectively, at a concentration of 250 µg/mL, these rates were better than that of the positive control agent, carbendazim (78.6%). The protective and curative effects of compounds 7 and 9 were also better than that of positive control, at the same concentration. Moreover, the mechanistic study showed that treatment with compound 9 significantly increased the structural tightness of tobacco leaves and directly affect the conidiospores of G. cichoracearum, thereby enhancing resistance. Compounds 7 and 9 could also induce systemic acquired resistance (SAR), directly regulating the expression of defense enzymes, defense genes, and plant semaphorins, which may further contribute to increased plant resistance. Based on the activity experiments and molecular dockings, the indole core structure may be the foundation of these compounds' anti-G. cichoracearum activity. Among them, the indole derivative parent structures of compounds 6, 7, and 9 exhibit strong effects. Moreover, the methoxy substitution in compound 7 can enhance their activity. By isolating and structurally identifying the above indole alkaloids, new candidates for anti-powdery mildew chemical screening were discovered, which could enhance the utilization of N. tabacum-derived fungi in pesticide development.

Bioorthogonal labeling and profiling of N6-isopentenyladenosine (i6A) modified RNA.

Chemical modifications in RNAs play crucial roles in diversifying their structures and regulating numerous biochemical processes. Since the 1990s, several hydrophobic prenyl-modifications have been discovered in various RNAs. Prenyl groups serve as precursors for terpenes and many other biological molecules. The processes of prenylation in different macromolecules have been extensively studied. We introduce here a novel chemical biology toolkit that not only labels i6A, a prenyl-modified RNA residue, by leveraging the unique reactivity of the prenyl group, but also provides a general strategy to incorporate fluorescence functionalities into RNAs for molecular tracking purposes. Our findings revealed that iodine-mediated cyclization reactions of the prenyl group occur rapidly, transforming i6A from a hydrogen-bond acceptor to a donor. Based on this reactivity, we developed an Iodine-Mediated Cyclization and Reverse Transcription (IMCRT) tRNA-seq method, which can profile all nine endogenous tRNAs containing i6A residues in Saccharomyces cerevisiae with single-base resolution. Furthermore, under stress conditions, we observed a decline in i6A levels in budding yeast, accompanied by significant decrease of mutation rate at A37 position. Thus, the IMCRT tRNA-seq method not only permits semi-quantification of i6A levels in tRNAs but also holds potential for transcriptome-wide detection and analysis of various RNA species containing i6A modifications.

What do windsurfers and kitesurfers in Germany know about surfer's ear and how is it influenced by protective measures?

OBJECTIVE: This study investigated the frequency of ear canal protection use and looked at its influence on external auditory exostosis severity and knowledge about external auditory exostosis among windsurfers and kitesurfers on the German coast. METHOD: This retrospective cross-sectional study interviewed 130 windsurfers and kitesurfers along the German coast on knowledge of external auditory exostosis, exposure time, use of neoprene hoods and earplugs, and otological complaints. Participants underwent bilateral video-otoscopic examination. RESULTS: Knowledge of external auditory exostosis was 'good' or 'excellent' in 78 of 130 (60 per cent) individuals and 'poor' or non-existent in 52 of 130 (40 per cent) individuals. Knowledge was positively correlated with hours of exposure, otological complaints and frequency of ear canal protection use. A significant negative influence of neoprene hood use on external auditory exostosis severity was shown. CONCLUSION: The positive effect of external auditory exostosis knowledge on the frequency of ear canal protection and the reduction of external auditory exostosis risk implies a need for health education on this topic.

The Application of Neoprene Diving Boots in Reduction of Feet Injuries in the Sowing Process Among the Rice Farmers in Thailand.

Foot injuries have been a problem among Thai farmers for a long time. The sowing process is one of the high-risk processes because farmers have to walk in the field to spray rice seed without footwear. Literature review showed that cuts from stepping on sharp material or snail shells were major sources of injury. Traditional footwear such as Ninja shoes or cloth socks have raised the questions regarding their ability in protection from such injuries. This study investigates using Neoprene diving boots to protect from foot injuries during the rice sowing process. The sample from this study were farmers from Sena District, Phra Nakhon Si Ayutthaya Province, Thailand. 29 farmer wearing Neoprene diving boots, 7 farmers wearing traditional Ninja shoes, and 19 farmers wearing cloth socks were asked to work in the sowing process and interviewed about any foot injuries that may have occurred. The statistical test showed there were no significant differences in characteristics among each group of farmers, except for work experience. The results show that there were no foot injuries in farmers wearing Neoprene diving boots, whereas 73% of farmers wearing Ninja shoes, and 14% of farmers wearing cloth socks still had foot injuries. Most injuries were alaceration that were caused by the golden apple snail. The satisfaction survey showed that farmers were satisfied and strongly satisfied with all of the aesthetics, utilization, and functionality factors. This study suggested that the Neoprene diving boots can be recommended for farmers to use as safeguarding against foot injuries in the rice sowing process.

Acrylates in artificial nails-Results of product analyses and glove penetration studies.

BACKGROUND: Artificial nail materials are mixtures that are prone to contain several sensitizing (meth)acrylates. It is not known whether the listing of (meth)acrylates is correct in these products' packages. Protective gloves suited for nail work are needed. OBJECTIVES: To analyse (meth)acrylates in gel nail and acrylic nail products chemically and to compare the results with the information in the product labels, and to study penetration of artificial nail materials through selected disposable gloves. METHODS: We analysed 31 gel nail products and 6 acrylic nail products for their (meth)acrylate content by gas chromatography-mass spectrometry (GC-MS). We tested the penetration of two nail products through three disposable gloves: nitrile rubber, neoprene rubber and polyvinyl chloride (PVC). RESULTS: Altogether 32/37 products contained (meth)acrylates. In all of them, there was discrepancy between the listed (meth)acrylates and those discovered in the analysis. The commonest (meth)acrylates were hydroxyethyl methacrylate (HEMA, 20/37 samples) and hydroxypropyl methacrylate (HPMA, 9/37 samples), but many of the product packages failed to declare them. Isobornyl acrylate (IBA) was discovered in nine gel nail products. The neoprene glove could withstand nail gel for 20 min and thin nitrile glove and PVC glove for 5 min. Acrylic nail liquid penetrated through disposable gloves quickly. CONCLUSIONS: Labelling of artificial nail products was notably incorrect on most products. Requirements for product labelling must be updated so that the risk of sensitization associated with artificial nail products is clearly indicated. Disposable gloves can probably be used short-term in gel nail work, whereas disposable gloves do not protect the user from acrylic nail liquids.

Mechanical characterization of human skin-A non-invasive digital twin approach using vibration-response integrated with numerical methods.

This paper proposes an innovative approach to identify elastic material properties and mass density of soft tissues based on interpreting their mechanical vibration response, externally excited by a mechanical indenter or acoustic waves. A vibration test is performed on soft sheets to measure their response to a continuous range of excitation frequencies. The frequency responses are collected with a pair of high-speed cameras in conjunction with 3-D digital image correlation (DIC). Two cases are considered, including suspended/fully-free rectangular neoprene sheets as artificial tissue cutout samples and continuous layered human skin vibrations. An efficient theoretical model is developed to analytically simulate the free vibrations of the neoprene artificial sheet samples as well as the continuous layered human skins. The high accuracy and validity of the presented analytical simulations are demonstrated through comparison with the DIC measurements and the conducted frequency tests, as well as a number of finite element (FE) modeling. The developed analytical approach is implemented into a numerical algorithm to perform an inverse calculation of the soft sheets' elastic properties using the imported experimental vibration results and the predicted system's mass via the system equivalent reduction/expansion process (SEREP) method. It is shown that the proposed frequency-dependent inverse approach is capable of rapidly predicting the material properties of the tested samples with high accuracy.

Abdominal aortic branches of red-rumped agouti (Dasyprocta leporina Linnaeus, 1758).

Understanding the cardiovascular system is fundamental in diagnosing pathologies and interpreting exams, such as contrast radiographs. In this context, the present study describes the collateral abdominal aorta artery branches of red-rumped agouti. Ten red-rumped agoutis, six males and four females, were assessed. The vascular system was perfused with Neoprene 450 latex coloured with a yellow pigment, dissected and analysed. Three euthanized animals were perfused with a barium sulfate solution (1 g mL-1 ) associated with latex Neoprene 450 at a 1:3 ratio to obtain contrast-enhanced radiographs. The abdominal aorta emitted the celiac artery, which in turn originated the left gastric, hepatic and splenic arteries. The second collateral branch comprised the cranial mesenteric artery, followed by the renal arteries, which emitted the adrenal arteries, with the caudal emergence of the gonadal arteries. The caudal mesenteric artery appeared in a caudal direction. The abdominal aorta divided after reaching the pelvic cavity entrance, originating the right and left common iliac arteries. Before its bifurcation, the abdominal aorta dorsocaudally emitted its last collateral branch, the median sacral artery. The collateral branches of the aorta, therefore, resemble previously described rodent patterns, with few variations.

Influence of neoprene ankle orthoses on dynamic balance during a vertical jump in healthy individuals and with sprain history: A cross-sectional study.

INTRODUCTION: A sprain describes an excessive amount of force or strain on a ligament, which may or may not lead to its rupture. Orthoses are among the most common modalities prescribed as a conservative treatment for ankle instability and sprain. OBJECTIVE: We aimed to analyse the effect of neoprene orthosis on the balance and functionality of healthy individuals and volunteers with lateral ankle sprains METHODS: We evaluated 12 healthy volunteers (control group) and 12 volunteers diagnosed with a sprain and/or instability (patient group). A total of 14 men and 10 women participated in the study, with an average age of 26.15 (± 4.40) years. The volunteers' tasks consisted of performing vertical bipodal and unipodal jumps on a force platform, which were recorded in a video from the lateral view of the lower limb for posterior evaluation of the knee and ankle angles. Mann-Whitney and Wilcoxon tests were used for comparisons, considering p < 0.05 level of significance. RESULTS: The control group presented a decrease in ground reaction force when using Orthosis during the bipodal jump (p < 0.05). A decrease in anteroposterior force displacement was also observed in the left unipodal jump (p < 0.01). The patient group presented an increase in force and moment of medial-lateral displacement for both bipodal (p < 0.02) and left unipodal jumps with Orthosis (p < 0.02). A kinematic analysis showed that the control group presented the smallest knee flexion angle (p < 0.01), while the patient group presented the smallest dorsiflexion ankle angle in the bipodal jump when using orthosis (p < 0.01). CONCLUSION: We concluded that orthosis had influence on individuals' balance and joint angles. In healthy individuals presented better balance with and without orthosis and greater flexion with orthosis in the bipodal jump, regarding to the patient group presented smaller oscillations in the unipodal jump with orthosis and showed smaller knee flexion and ankle dorsiflexion.

Preliminary study of elastic-tension digital neoprene orthoses for proximal interphalangeal joint flexion contracture.

Flexion contracture of the proximal interphalangeal joint (PIPJ) is one of the most frequent complications in finger trauma. Orthoses are the most widely used method to optimize total end-range time (TERT). No previous studies showed that an elastic tension orthosis could be applied for longer than 12 h. We aimed to demonstrate that the elastic-tension digital neoprene orthosis (ETDNO) can achieve higher TERT and therefore better range of motion than other elastic-tension orthoses (ETO) described in the literature. A prospective study of treatment of PIPJ flexion contracture included 10 PIP joints in 8 patients who met the selection criteria. They were instructed to use the ETDNO for around 23 h per day as far as possible, during a period of 3 weeks. Patients reported a mean TERT of 20.6 h a day. PIPJ contracture improved by a mean Torque Range of Motion (TROM) of 23.5° at 500 g and 22.9° at 800 g of passive extension force during the 3-week treatment. Based on the results of this study, the ETDNO appears to offer a highly effective approach for improving PIPJ flexion contracture, increasing range of motion in extension. ETDNO's efficacy probably lies in the significantly improved comfort and low-profile design, enabling excellent compliance and thus optimizing TERT. LEVEL OF EVIDENCE: Level III.

A new monitoring approach for sustainability assessment of subsurface utilities gasket materials against gasoline and chlorinated solvents: Field evaluation and model development.

Once installed, underground concrete pipes with rubber gaskets might be exposed to contaminated soil and groundwater. A pipe material monitoring capsule (PMMC) has been developed to evaluate volatile organic compounds (VOCs) breaking through three types of pipe gaskets; Neoprene, Buna-N, and Viton. The PMMCs were deployed in three contaminated sites: two with gasoline and one with chlorinated solvent (CS). A 3-D field-domain numerical model has been developed for each site to calibrate equivalent hydraulic parameters of each gasket material (ke, D) against benzene and PCE diffusion. The calibrated parameters were then used to compute the concentrations as well as rate of breakthrough of the two study contaminants. A protocol was developed for installing/retrieval of PMMCs to monitor PCE and benzene mass breaking through the gasket material with time. Employing PMMC, benzene concentrations breaking through the Neoprene and Buna-N after 4 months were approximately 70% and 60% respectively of the monitoring wells concentration. The corresponding value for PCE breakthrough after 4 months was 60% for both the Neoprene and Buna-N. Both gasket materials of Neoprene and Buna-N yielded similar performances, including higher rate of contaminant breakthrough compared to Viton. A nonlinear relationship of mass breaking through the gaskets of benzene and PCE with time was discerned from the modeling and field data.

Structural Basis of Substrate Promiscuity and Catalysis by the Reverse Prenyltransferase N-Dimethylallyl-l-tryptophan Synthase from Fusarium fujikuroi.

The regiospecific prenylation of an aromatic amino acid catalyzed by a dimethylallyl-l-tryptophan synthase (DMATS) is a key step in the biosynthesis of many fungal and bacterial natural products. DMATS enzymes share a common "ABBA" fold with divergent active site contours that direct alternative C-C, C-N, and C-O bond-forming trajectories. DMATS1 from Fusarium fujikuroi catalyzes the reverse N-prenylation of l-Trp by generating an allylic carbocation from dimethylallyl diphosphate (DMAPP) that then alkylates the indole nitrogen of l-Trp. DMATS1 stands out among the greater DMATS family because it exhibits unusually broad substrate specificity: it can utilize geranyl diphosphate (GPP) or l-Tyr as an alternative prenyl donor or acceptor, respectively; it can catalyze both forward and reverse prenylation, i.e., at C1 or C3 of DMAPP; and it can catalyze C-N and C-O bond-forming reactions. Here, we report the crystal structures of DMATS1 and its complexes with l-Trp or l-Tyr and unreactive thiolodiphosphate analogues of the prenyl donors DMAPP and GPP. Structures of ternary complexes mimic Michaelis complexes with actual substrates and illuminate active site features that govern prenylation regiochemistry. Comparison with CymD, a bacterial enzyme that catalyzes the reverse N-prenylation of l-Trp with DMAPP, indicates that bacterial and fungal DMATS enzymes share a conserved reaction mechanism. However, the narrower active site contour of CymD enforces narrower substrate specificity. Structure-function relationships established for DMATS enzymes will ultimately inform protein engineering experiments that will broaden the utility of these enzymes as useful tools for synthetic biology.

Farnesyl pyrophosphate compartmentalization in the green microalga Chlamydomonas reinhardtii during heterologous (E)-α-bisabolene production.

BACKGROUND: Eukaryotic algae have recently emerged as hosts for metabolic engineering efforts to generate heterologous isoprenoids. Isoprenoid metabolic architectures, flux, subcellular localization, and transport dynamics have not yet been fully elucidated in algal hosts. RESULTS: In this study, we investigated the accessibility of different isoprenoid precursor pools for C15 sesquiterpenoid generation in the cytoplasm and chloroplast of Chlamydomonas reinhardtii using the Abies grandis bisabolene synthase (AgBS) as a reporter. The abundance of the C15 sesquiterpene precursor farnesyl pyrophosphate (FPP) was not increased in the cytosol by co-expression and fusion of AgBS with different FPP synthases (FPPSs), indicating limited C5 precursor availability in the cytoplasm. However, FPP was shown to be available in the plastid stroma, where bisabolene titers could be improved several-fold by FPPSs. Sesquiterpene production was greatest when AgBS-FPPS fusions were directed to the plastid and could further be improved by increasing the gene dosage. During scale-up cultivation with different carbon sources and light regimes, specific sesquiterpene productivities from the plastid were highest with CO2 as the only carbon source and light:dark illumination cycles. Potential prenyl unit transporters are proposed based on bioinformatic analyses, which may be in part responsible for our observations. CONCLUSIONS: Our findings indicate that the algal chloroplast can be harnessed in addition to the cytosol to exploit the full potential of algae as green cell factories for non-native sesquiterpenoid generation. Identification of a prenyl transporter may be leveraged for further extending this capacity.

Three Australian Lepidosperma Labill. Species as sources of prenylated and oxyprenylated derivatives of piceatannol, resveratrol and pinosylvin: Melatoninergic binding and inhibition of quinone reductase 2.

Prenylated and hydroxyprenylated piceatannol, resveratrol and pinosylvin derivatives were isolated from resin produced by three Australian Lepidosperma Labill. Species (Cyperaceae). From L. congestum R.Br. one known compound, 3',5'-bis-prenyl-E-resveratrol, and five undescribed compounds were isolated, 3'-O-prenyl-5'-prenyl-E-piceatannol, 5',6'-bis-prenyl-E-piceatannol, 5'-prenyl-E-piceatannol, 3',5'-bis(3-hydroxy-3-methylbutyl)-E-resveratrol and 3',5'-bis-E-hydroxyprenyl-E-resveratrol. From L. gunnii Boeckeler one undescribed compound was isolated, 3'-E-hydroxyprenyl-5'-Z-hydroxyprenyl-E-resveratrol. From L. laterale R.Br. six undescribed compounds were isolated, 3-O-prenyl-E-pinosylvin, 3-O-Z-hydroxyprenyl-E-pinosylvin, 3'-Z-hydroxyprenyl-E-resveratrol, 3-O-Z-hydroxyprenyl-E-resveratrol, 3-O-Z-hydroxyprenyl-4'-O-methyl-E-resveratrol, and 3-O-prenyl-3'-δ,δ'-dihydroxyprenyl-E-resveratrol. Compounds, including a reference compound 3-O-prenyl-3'-O-methyl-E-piceatannol, were screened in an assay for melatoninergic binding to MT1 and MT2 receptors and binding to QR2/MT3 enzyme, and for inhibition of QR2/MT3 in a functional assay. Strong binding was observed for 3-O-Z-hydroxyprenyl-E-resveratrol with a Ki of 0.022 nM and the strongest inhibition of QR2/MT3 observed was for the reference compound, 3-O-prenyl-3'-O-methyl-E-piceatannol, with an inhibition of 61% at 1 µM and 95% at 10 µM. The three most active binders and inhibitors of QR2/MT3 were found to have a common substructure corresponding to 3-O-prenylresveratrol.

Characterization of prenylated phenolics in Glycyrrhiza uralensis by offline two-dimensional liquid chromatography/mass spectrometry coupled with mass defect filter.

Prenylated phenolics are an important class of natural products. In this study, an efficient strategy was established to systematically characterize the prenylated phenolics in Glycyrrhiza uralensis, a popular herbal medicine. Firstly, offline two-dimensional liquid chromatography/mass spectrometry (2DLC/MS) coupled with mass defect filter (MDF) technology was used to preliminarily detect 1631 potential prenylated phenolics. Secondly, the tandem mass spectrometry fragmentation features of different types of prenylated phenolics were investigated using 29 reference standards. Diagnostic fragmentations included neutral loss (NL) of 42 Da for the annular type and NL of 56 Da for the catenulate type in the positive ion mode, and NL of 56 Da for A-ring prenyl groups and NL of 69 Da for B-ring prenyl groups in the negative ion mode. As a result, the prenylation types, substitution sites, and adjacent OH and OCH3 substitutions of 320 prenylated phenolics in G. uralensis were rapidly characterized. Moreover, three prenylated dihydrostilbenes were purified from the aerial part of G. uralensis to verify the structural characterizations.

Development of Biocompatible Ene-Ligation Enabled by Prenyl-Based ß-Caryophyllene with Triazoline/Selectfluor under Physiological Conditions.

Here, we first report a rapid and highly selective biocompatible ligation that proceeds via a strain-promoted prenyl-involved [2, 3]-Ene rearrangement process. We demonstrate the usefulness of naturally occurring strain-promoted ß-caryophyllene with triazoline (PTAD)/Selectfluor in the study of tagging molecule-of-interest. Experiments in peptide (Histone H3 (1-21) and Myhc (614-629)) and protein (BSA, ßLG, and HSP40) models exemplified the utility of the Ene-ligation for in vivo imaging and tracking.

Enzymatic formation of a prenyl ß-carboline by a fungal indole prenyltransferase.

CdpNPT from Aspergillus fumigatus is a fungal indole prenyltransferase (IPT) with remarkable substrate promiscuity to generate prenylated compounds. Our first investigation of the catalytic potential of CdpNPT against a ß-carboline, harmol (1), revealed that the enzyme also accepts 1 as the prenyl acceptor with dimethylallyl diphosphate (DMAPP) as the prenyl donor and selectively prenylates the C-6 position of 1 by the "regular-type" dimethylallylation to produce 6-(3-dimethylallyl)harmol (2). Furthermore, our X-ray crystal structure analysis of the C-His6-tagged CdpNPT (38-440) truncated mutant complexed with 1 and docking studies of DMAPP to the crystal structure of the CdpNPT (38-440) mutant suggested that CdpNPT could employ the two-step prenylation system to produce 2.

Collateral aortic branches in the collared peccary (Pecari tajacu Linnaeus, 1758).

The determination of arterial vascular distribution patterns can contribute to more detailed knowledge on arterial systems. In this context, the aim of the present study was to describe the collateral aortic branches in the collared peccary, aiming to define a standard model for this species, providing information through comparative anatomy for analysis of some evolutionary aspects of the order Artiodactyla. Ten young male animals were employed. The vascular system was washed with a saline solution and then perfused with Neoprene 450 latex coloured with red or yellow pigment, followed by collateral aorta branch dissections and analyses. The contrasted digital radiography technique was applied to two animals, which were initially perfused with a barium sulphate solution (1 g/ml) and Neoprene 450 latex at a 1:3 ratio, and subsequently, the digital radiographic examination was performed. The aortic arch of the collared peccary emitted the brachiocephalic trunk and the left subclavian artery, while eight symmetric pairs of dorsal intercostal arteries originated from the thoracic aorta. The abdominal aorta, in turn, exhibited the celiac, cranial mesenteric, renal, caudal mesenteric, testicular, external iliac, internal iliac and sacral arteries as the collateral branches in all studied animals. Therefore, no relevant variations were observed regarding the arrangement of the arterial distribution of the aorta, thus suggesting a static standard model in the collared peccary.

A Randomized Controlled Trial Comparing a Patella-Stabilizing, Motion-Restricting Knee Brace Versus a Neoprene Nonhinged Knee Brace After a First-Time Traumatic Patellar Dislocation.

BACKGROUND: A traumatic lateral patellar dislocation is a common injury in adolescents and young adults. The majority of first-time dislocations can be treated nonoperatively. Various types of knee braces are used for nonoperative treatment, but evidence on the most preferable bracing method is lacking. PURPOSE: To evaluate the efficacy of a patella-stabilizing, motion-restricting knee brace versus a neoprene nonhinged knee brace for the treatment of a first-time traumatic patellar dislocation at 3 years of follow-up. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A total of 101 skeletally mature patients with a first-time traumatic patellar dislocation were enrolled in the study. After exclusion criteria were applied, 79 patients with a first-time traumatic patellar dislocation were randomized and allocated into 2 study groups: group A, with a patella-stabilizing, motion-restricting knee brace (hinged to allow knee range of motion [ROM] of 0°-30°) and group B, with a neoprene nonhinged knee brace (not restricting any knee motion). Both groups received similar physical therapy instructions and were advised to use the brace continuously for 4 weeks. Overall, 64 patients completed the trial. RESULTS: The redislocation rate in group A was 34.4% (11/32) and in group B it was 37.5% (12/32) (risk difference, -3.1% [95% CI, -26.6% to 20.3%]; P = .794). Patients in group A had less knee ROM than those in group B at 4 weeks (90° vs 115°, respectively; P < .001) and 3 months (125° vs 133°, respectively; P = .028). Patients in group A had more quadriceps muscle atrophy than patients in group B at 4 weeks (24/32 vs 16/32, respectively; P = .048) and 3 months. At 6 months, patients in group B reported better functional outcomes than patients in group A (Kujala score mean difference, 4.6; P = .012), although no clinically relevant difference was found at 3 years. CONCLUSION: The use of a patella-stabilizing, motion-restricting knee brace for 4 weeks after a first-time traumatic patellar dislocation did not result in a statistically significant reduction in redislocations versus a neoprene nonhinged knee brace, although this trial was underpowered to detect more modest differences. Knee immobilization was associated with quadriceps muscle atrophy, less knee ROM, and worse functional outcomes in the first 6 months after the injury. REGISTRATION: NCT01344915 (ClinicalTrials.gov identifier).

Escherichia coli tRNA 2-selenouridine synthase SelU selects its prenyl substrate to accomplish its enzymatic function.

Bacterial tRNA 2-selenouridine synthase (SelU) in vitro converts S2U-RNA to its selenium analog (Se2U-RNA) in a two-step process: (i) geranylation of S2U-RNA (with geranyl pyrophosphate, gePP), and (ii) selenation of the resulting geS2U-RNA (with the selenophosphate anion, SePO33-). Using an S2U-containing anticodon stem-loop fragment derived from tRNALys (S2U-RNA) and recombinant SelU with an MBP tag, we found that only geranyl (C10) pyrophosphate is the substrate for this enzyme, while other pyrophosphates such as isopentenyl (C5), dimethylallyl (C5), farnesyl (C15) and geranylgeranyl (C20) are not. Interestingly, methyl (C1)- and C5-, C10-, and C15-prenyl-containing S2U-RNAs (which were chemically obtained) underwent the selenation reaction promoted by SelU, although the Se2U-RNA product was obtained in decreasing yields in the following order: geranyl ≥ farnesyl > dimethylallyl ≫ methyl. Microscale thermophoresis showed an affinity between gePP and SelU in the micromolar range, while the other pyrophosphates tested, such as isopentenyl, dimethylallyl, farnesyl and geranylgeranyl, either did not bind to the protein or their binding affinity was above 1 mM. These results agree well with the in silico analysis, with gePP being the best binding substrate (the lowest relative free energy of binding (ΔG) and a small solvent-accessible surface area (SASA)). These results suggest that SelU has high substrate specificity for the prenylation reaction (only gePP is accepted), whereas there is little discrimination for the selenation reaction. We therefore suggest that only gePP and the geranylated tRNA serve as substrates for the conversion of 2-thio-tRNAs to 2-seleno-tRNAs, as it is found in the bacterial system.

A State-of-the-art Review and Prospective Therapeutic Applications of Prenyl Flavonoids as Chemosensitizers against Antifungal Multidrug Resistance in Candida albicans.

Multidrug resistance (MDR) in the opportunistic pathogen Candida albicans is defined as non-susceptibility to at least one agent in two or more drug classes. This phenomenon has been increasingly reported since the rise in the incidence of fungal infections in immunocompromised patients at the end of the last century. After the discovery of efflux pump overexpression as a principal mechanism causing MDR in Candida strains, drug discovery targeting fungal efflux transporters has had a growing impact. Chemosensitization aims to enhance azole intracellular concentrations through combination therapy with transporter inhibitors. Consequently, the use of drug efflux inhibitors combined with the antifungal agent will sensitize the pathogen. As a result, the use of lower drug concentrations will reduce possible adverse effects on the host. Through an extensive revision of the literature, this review aims to provide an exhaustive and critical analysis of the studies carried out in the past two decades regarding the chemosensitization strategy to cope with multidrug resistance in C. albicans. This work provides a deep analysis of the research on the inhibition of drug-efflux membrane transporters by prenylated flavonoids and the interactions of these phytocompounds with azole antifungals as an approach to chemosensitize multidrug-resistant C. albicans strains. We highlight the importance of prenylflavonoids and their particular chemical and pharmacological characteristics that make them excellent candidates with therapeutic potential as chemosensitizers. Finally, we propose the need for further research on prenyl flavonoids as inhibitors of drug-efflux mediated fungal resistance.