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1.
J Neurogastroenterol Motil ; 30(3): 332-342, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38972868

RESUMO

Background/Aims: Ineffective esophageal motility (IEM) is common in patients with gastroesophageal reflux disease (GERD) and can be associated with poor esophageal contraction reserve on multiple rapid swallows. Alterations in the esophageal microbiome have been reported in GERD, but the relationship to presence or absence of contraction reserve in IEM patients has not been evaluated. We aim to investigate whether contraction reserve influences esophageal microbiome alterations in patients with GERD and IEM. Methods: We prospectively enrolled GERD patients with normal endoscopy and evaluated esophageal motility and contraction reserve with multiple rapid swallows during high-resolution manometry. The esophageal mucosa was biopsied for DNA extraction and 16S ribosomal RNA gene V3-V4 (Illumina)/full-length (Pacbio) amplicon sequencing analysis. Results: Among the 56 recruited patients, 20 had normal motility (NM), 19 had IEM with contraction reserve (IEM-R), and 17 had IEM without contraction reserve (IEM-NR). Esophageal microbiome analysis showed a significant decrease in microbial richness in patients with IEM-NR when compared to NM. The beta diversity revealed different microbiome profiles between patients with NM or IEM-R and IEM-NR (P = 0.037). Several esophageal bacterial taxa were characteristic in patients with IEM-NR, including reduced Prevotella spp. and Veillonella dispar, and enriched Fusobacterium nucleatum. In a microbiome-based random forest model for predicting IEM-NR, an area under the receiver operating characteristic curve of 0.81 was yielded. Conclusions: In symptomatic GERD patients with normal endoscopic findings, the esophageal microbiome differs based on contraction reserve among IEM. Absent contraction reserve appears to alter the physiology and microbiota of the esophagus.

2.
J Neuroeng Rehabil ; 21(1): 116, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997727

RESUMO

OBJECTIVE: This study explored the impact of one session of low-pressure leg blood flow restriction (BFR) during treadmill walking on dual-task performance in older adults using the neurovisceral integration model framework. METHODS: Twenty-seven older adults participated in 20-min treadmill sessions, either with BFR (100 mmHg cuff pressure on both thighs) or without it (NBFR). Dual-task performance, measured through light-pod tapping while standing on foam, and heart rate variability during treadmill walking were compared. RESULTS: Following BFR treadmill walking, the reaction time (p = 0.002) and sway area (p = 0.012) of the posture dual-task were significantly reduced. Participants exhibited a lower mean heart rate (p < 0.001) and higher heart rate variability (p = 0.038) during BFR treadmill walking. Notably, BFR also led to band-specific reductions in regional brain activities (theta, alpha, and beta bands, p < 0.05). The topology of the EEG network in the theta and alpha bands became more star-like in the post-test after BFR treadmill walking (p < 0.005). CONCLUSION: BFR treadmill walking improves dual-task performance in older adults via vagally-mediated network integration with superior neural economy. This approach has the potential to prevent age-related falls by promoting cognitive reserves.


Assuntos
Frequência Cardíaca , Caminhada , Humanos , Idoso , Masculino , Feminino , Caminhada/fisiologia , Frequência Cardíaca/fisiologia , Teste de Esforço , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Fluxo Sanguíneo Regional/fisiologia , Desempenho Psicomotor/fisiologia , Perna (Membro)/fisiologia
3.
J Sci Food Agric ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38925544

RESUMO

BACKGROUND: Microbiota succession determines the flavor and quality of fermented foods. Quantitative PCR-based quantitative microbiome profiling (QMP) has been applied broadly for microbial analysis from absolute abundance perspectives, transforming microbiota ratios into counts by normalizing 16S ribosomal RNA (16S rRNA) gene sequencing data with gene copies quantified by quantitative PCR. However, the application of QMP in fermented foods is still limited. RESULTS: QMP elucidated microbial succession of Taiwanese pickled cabbage. In the spontaneous first-round fermentation (FR), the 16S rRNA gene copies of total bacteria increased from 6.1 to 10 log copies mL-1. The dominant lactic acid bacteria genera were successively Lactococcus, Leuconostoc and Lactiplantibacillus. Despite the decrease in the proportion of Lactococcus during the succession, the absolute abundance of Lactococcus still increased. In the backslopping second-round fermentation (SR), the total bacteria 16S rRNA gene copies increased from 7.6 to 9.9 log copies mL-1. The addition of backslopping starter and vinegar rapidly led to a homogenous microbial community dominated by Lactiplantibacillus. The proportion of Lactiplantibacillus remained consistently around 90% during SR, whereas its absolute abundance exhibited a continuous increase. In SR without vinegar, Leuconostoc consistently dominated the fermentation. CONCLUSION: The present study highlights that compositional analysis would misinterpret microbial dynamics, whereas QMP reflected the real succession profiles and unveiled the essential role of vinegar in promoting Lactiplantibacillus dominance in backslopping fermentation of Taiwanese pickled cabbage. Quantitative microbiome profiling (QMP) was found to be a more promising approach for the detailed observation of microbiome succession in food fermentation compared to compositional analysis. © 2024 Society of Chemical Industry.

4.
J Chin Med Assoc ; 87(7): 686-690, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38771089

RESUMO

BACKGROUND: Ligamentous laxity, cartilage wear, and diffuse synovitis are frequently seen in thumb basal joint arthritis. Although these degenerative changes may be mild for the majority, they have the potential to cause discomfort during movement and compromised hand function. This study assesses the long-term outcomes of arthroscopic debridement, synovectomy, and thermal shrinkage in managing early-stage basal joint arthritis. METHODS: We retrospectively reviewed patients with basal joint arthritis who underwent arthroscopic debridement, synovectomy, and thermal shrinkage between November 2010 and January 2021 by a single surgeon at our medical institute. We assessed functional outcomes, thumb range of motion, perioperative nonsteroidal anti-inflammatory drug (NSAID) use, return to work and satisfaction level. RESULTS: A total of 12 patients (13 hands), with a mean follow-up of 72 months, were included in this study. Significant improvements were observed in pain scores and functional outcomes, along with a reduction in postoperative NSAID use. Patients also reported a relatively quick return to work and a high satisfaction level. CONCLUSION: The study highlights the benefits of arthroscopic intervention, providing a minimally invasive approach with favorable long-term outcomes for patients with symptomatic basal joint arthritis.


Assuntos
Artroscopia , Desbridamento , Sinovectomia , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Artrite/cirurgia , Adulto
5.
J Hand Surg Am ; 49(4): 321-328, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38300191

RESUMO

PURPOSE: Recent biomechanical studies have highlighted the importance of foveal reinsertion when repairing triangular fibrocartilage complex (TFCC) injury with foveal tears. However, clinical studies comparing different repair techniques are scarce. We compared the clinical outcomes of suture anchor repair and rein-type capsular suture in patients with TFCC palmer 1B foveal tears with a minimum of 2-year follow-up. METHODS: This was a single-surgeon, single-center, retrospective, comparative study. We included patients who underwent TFCC repair surgery due to a foveal tear from December 2013 to October 2018 with a minimum follow-up of 24 months. Postoperative Quick Disabilities of Arm, Shoulder, and Hand (QuickDASH) score, Modified Mayo Wrist Score, visual analogue scale for pain, wrist range of motion, and grip strength were compared. We also measured the maximal ulnar head displacement with dynamic ultrasound to quantify distal radioulnar joint stability. RESULTS: In total, 103 patients were in the suture anchor group (group A) and 84 patients in the rein-type capsular suture group (group B). The mean follow-up time exceeded three years for both groups. There was a minimal difference regarding QuickDASH score, visual analogue scale for pain, and grip strength ratio between the two groups. The rein-type group had significantly better Modified Mayo Wrist Score. The suture anchor group showed better distal radioulnar joint stability with dynamic ultrasound, but was more limited in ulnar deviation. However, these differences are most likely clinically insignificant. CONCLUSIONS: Both suture anchor repair and rein-type capsular suture yielded satisfactory results for TFCC 1B foveal tear in a minimum of 2-year follow-up. The functional scores were similar, and no major complications or recurrent instability were noted in either group. TYPE OF STUDY/LEVEL OF EVIDENCE: Retrospective Therapeutic Comparative Investigation IV.


Assuntos
Fibrocartilagem Triangular , Traumatismos do Punho , Humanos , Fibrocartilagem Triangular/lesões , Seguimentos , Estudos Retrospectivos , Âncoras de Sutura , Articulação do Punho/cirurgia , Dor , Traumatismos do Punho/cirurgia , Artroscopia/métodos , Suturas , Técnicas de Sutura
6.
J Orthop Surg Res ; 18(1): 661, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37670343

RESUMO

PURPOSE: The objective of this study was to investigate the potential of arthroscopic scapholunate ligament repair and dorsal capsulodesis with suture anchor as a treatment option for patients experiencing symptomatic acute and subacute (< 3 months) scapholunate instability. METHODS: From Jan. 2017 to Jan 2020, 19 wrists with acute or subacute tears of the SL ligament with symptomatic instability were treated with arthroscopic SL repair and dorsal capsulodesis with a suture anchor. The average time from injury to operation was 8.8 weeks (range, 4-11 weeks) and the regular follow-up mean duration at our clinic was 26.5 months (range, 24-32 months). The pain score according to the visual analog scale, wrist range of motion, grip strength, radiographic outcomes and functional outcomes according to the Modified Mayo Wrist Score (MMWS) were evaluated preoperatively and postoperatively during the follow-up period. RESULTS: All 19 patients had rupture and dissociation of the SL ligament in the radiocarpal joint. The total arc of wrist motion in the flexion-extension plane loss averaged 5.1° (P > .01).The Wilcoxon signed-rank test was used to compare the results: grip force improved significantly with 14.7% improvement of that on the normal side (P < .01); the postoperative MMWS was significantly better than the preoperative scores (P < .01). Of 19 patients of the series, 18 patients (94.7%) achieved good or excellent results according to the MMWS and 16 patients (84.2%) resumed their previous activities. Only one patient (5.3%) had residual laxity of the scapholunate ligament joint at 15 months of follow-up. CONCLUSIONS: At a minimum of two years of follow-up, patients with acute or subacute symptomatic dissociation of scapholunate ligament instability who underwent arthroscopic scapholunate ligament repair and dorsal capsulodesis with suture anchor treatment had satisfactory results. LEVEL OF EVIDENCE: Level IV, case series.


Assuntos
Âncoras de Sutura , Articulação do Punho , Humanos , Punho , Ligamentos Articulares , Instituições de Assistência Ambulatorial
7.
J Chin Med Assoc ; 86(11): 981-984, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37729606

RESUMO

BACKGROUND: The ideal scenario for ulnar nerve repair is primary end-to-end neurorrhaphy in a tension-free environment. However, this could be complicated by soft tissue loss, scarring, and neuroma formation in a delayed injury, creating a nerve defect. With a wrist-level nerve defect, a flexion position can help shorten the nerve gap; however, maintaining the position can be challenging intraoperatively and postoperatively. METHODS: Previously, we proposed our method of using a 1.6-mm K wire for radius-lunate-capitate pinning of the wrist in flexion to minimize the nerve gap, thereby facilitating neuroma excision and end-to-end neurorrhaphy in delayed ulnar nerve injury. In this study, we elaborate our method and present our case series. RESULTS: From October 2018 to July 2020, five patients (mean age: 48.2 years; mean delay from injury to surgery: 84.6 days; mean follow-up: 17.5 months) were retrospectively reviewed. The mean flexion fixation angle was 52°, and the K wire was removed at an average of 5.1 weeks postoperatively. All patients were followed up for a minimum of 12 months. All patients achieved M4 and S3 or S3+ neurologically (according to the criteria of the Nerve Injuries Committee of the British Medical Research Council). The mean disabilities arm, shoulder, and hand score was 14.1. The mean grasp and pinch strengths were, respectively, 76.8% and 63.6% of the contralateral hand. All wrist range of motion returned to normal within 12 weeks. No complications were noted intraoperatively or postoperatively. CONCLUSION: Our study showed that radiocarpal pinning of the wrist in flexion was safe and convenient to minimize the nerve gap and to facilitate end-to-end neurorrhaphy in limited-sized wrist-level ulnar nerve defects.


Assuntos
Neuroma , Traumatismos do Punho , Humanos , Pessoa de Meia-Idade , Punho , Nervo Ulnar/lesões , Nervo Ulnar/cirurgia , Estudos Retrospectivos , Articulação do Punho/cirurgia , Neuroma/complicações , Amplitude de Movimento Articular/fisiologia , Resultado do Tratamento , Traumatismos do Punho/complicações , Traumatismos do Punho/cirurgia
8.
Bioorg Chem ; 141: 106843, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37696148

RESUMO

In the present study, the undescribed schitriterpenoids, kadsujanonols A-I (1-9), and eleven reported compounds (10-20) were isolated from K. japonica L. vines. Their structures of 3,4-seco-schitriterpenoids were elucidated mainly by spectroscopic analyses including 1H-, 13C-, and 2D-NMR, IR, HRESIMS spectra. The spatial configurations were determined by the single-crystal X-ray diffraction analysis of kadsujapnonol A (1), 15, 17, and 18, CD data and computational analysis. Furthermore, all isolates were evaluated for the anti-neuroinflammatory activity on LPS-stimulated NO production in BV2 microglial cells and compounds 2, 4, 5, 7, 9, 11, 13-16, and 18 exposed better or comparable suppression abilities than PDTC. Among them, kadlongilactone B (14) showed the best significant inhibiting ability (IC50 = 0.87 µg/mL) and the effect is through the attenuation of the inflammatory transcription factor p65NF-κB. Preliminary structure-activity relationship revealed that δ-lactone at the side chain and 7-member lactone at C-3/C-4, and 3,4:9,10 ring opening are important.


Assuntos
Kadsura , Kadsura/química , Relação Estrutura-Atividade , Microglia , Lactonas , Lipopolissacarídeos/farmacologia , Estrutura Molecular
9.
IEEE Trans Image Process ; 32: 4677-4688, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37527318

RESUMO

In this paper, we propose an efficient deep learning pipeline for light field acquisition using a back-to-back dual-fisheye camera. The proposed pipeline generates a light field from a sequence of 360° raw images captured by the dual-fisheye camera. It has three main components: a convolutional network (CNN) that enforces a spatiotemporal consistency constraint on the subviews of the 360° light field, an equirectangular matching cost that aims at increasing the accuracy of disparity estimation, and a light field resampling subnet that produces the 360° light field based on the disparity information. Ablation tests are conducted to analyze the performance of the proposed pipeline using the HCI light field datasets with five objective assessment metrics (MSE, MAE, PSNR, SSIM, and GMSD). We also use real data obtained from a commercially available dual-fisheye camera to quantitatively and qualitatively test the effectiveness, robustness, and quality of the proposed pipeline. Our contributions include: 1) a novel spatiotemporal consistency loss that enforces the subviews of the 360° light field to be consistent, 2) an equirectangular matching cost that combats severe projection distortion of fisheye images, and 3) a light field resampling subnet that retains the geometric structure of spherical subviews while enhancing the angular resolution of the light field.

10.
Front Chem ; 11: 1223335, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426336

RESUMO

The Euphorbiaceae plant Euphorbia neriifolia L. is distributed widely in India, Thailand, Southeastern China, and Taiwan and used as a carminative and expectorant to treat several inflammation-related diseases, such as gonorrhoea, asthma, and cancer. In the course of our search for potential anti-inflammatory agents from the titled plant, 11 triterpenes from the stem of E. neriifolia were isolated and reported in our previous endeavor. Given its rich abundance in triterpenoids, the ethanolic extract in this follow-up exploration has led to the isolation of additional eight triterpenes, including six new euphanes-neritriterpenols H and J-N (1 and 3-7)-one new tirucallane, neritriterpenol I (2), and a known compound, 11-oxo-kansenonol (8). Their chemical structures were elucidated on the basis of spectroscopic data, including 1D- and 2D NMR, and HRESIMS spectra. The absolute stereochemistry of neritriterpenols was determined by single-crystal X-ray diffraction analysis, ICD spectra, and DP4+ NMR data calculations. Compounds 1-8 were also evaluated for their anti-inflammatory activity by using lipopolysaccharide (LPS)-stimulated IL-6 and TNF-α on RAW 264.7 macrophage cells. Intriguingly, the euphane-type triterpenes (1 and 3-8) showed an inhibitory effect on LPS-induced IL-6 but not on TNF-α, while tirucallane-type triterpene 2 showed strong inhibition on both IL-6 and TNF-α.

11.
Nat Commun ; 14(1): 2528, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-37137912

RESUMO

Oxidized cysteine residues are highly reactive and can form functional covalent conjugates, of which the allosteric redox switch formed by the lysine-cysteine NOS bridge is an example. Here, we report a noncanonical FAD-dependent enzyme Orf1 that adds a glycine-derived N-formimidoyl group to glycinothricin to form the antibiotic BD-12. X-ray crystallography was used to investigate this complex enzymatic process, which showed Orf1 has two substrate-binding sites that sit 13.5 Å apart unlike canonical FAD-dependent oxidoreductases. One site could accommodate glycine and the other glycinothricin or glycylthricin. Moreover, an intermediate-enzyme adduct with a NOS-covalent linkage was observed in the later site, where it acts as a two-scissile-bond linkage facilitating nucleophilic addition and cofactor-free decarboxylation. The chain length of nucleophilic acceptors vies with bond cleavage sites at either N-O or O-S accounting for N-formimidoylation or N-iminoacetylation. The resultant product is no longer sensitive to aminoglycoside-modifying enzymes, a strategy that antibiotic-producing species employ to counter drug resistance in competing species.


Assuntos
Aminoglicosídeos , Cisteína , Cisteína/química , Ligantes , Sítios de Ligação , Antibacterianos , Cristalografia por Raios X , Glicina
12.
Mol Syst Biol ; 19(4): e11127, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36856068

RESUMO

Cancers represent complex autonomous systems, displaying self-sufficiency in growth signaling. Autonomous growth is fueled by a cancer cell's ability to "secrete-and-sense" growth factors (GFs): a poorly understood phenomenon. Using an integrated computational and experimental approach, here we dissect the impact of a feedback-coupled GTPase circuit within the secretory pathway that imparts secretion-coupled autonomy. The circuit is assembled when the Ras-superfamily monomeric GTPase Arf1, and the heterotrimeric GTPase Giαßγ and their corresponding GAPs and GEFs are coupled by GIV/Girdin, a protein that is known to fuel aggressive traits in diverse cancers. One forward and two key negative feedback loops within the circuit create closed-loop control, allow the two GTPases to coregulate each other, and convert the expected switch-like behavior of Arf1-dependent secretion into an unexpected dose-response alignment behavior of sensing and secretion. Such behavior translates into cell survival that is self-sustained by stimulus-proportionate secretion. Proteomic studies and protein-protein interaction network analyses pinpoint GFs (e.g., the epidermal GF) as key stimuli for such self-sustenance. Findings highlight how the enhanced coupling of two biological switches in cancer cells is critical for multiscale feedback control to achieve secretion-coupled autonomy of growth factors.


Assuntos
Células Eucarióticas , Proteômica , Transdução de Sinais , GTP Fosfo-Hidrolases
13.
Nat Prod Res ; : 1-8, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36606546

RESUMO

The spirohydantoin-containing cucurbitane-type triterpenoid, kaguacidine A (1), was isolated and purified from 95% ethanol extract of vines of Momordica charantia L. (Cucurbitaceae). Its unprecedented chemical structure, a spirohydantoin substituent at C-23 of cucurbitane, was elucidated by extensive spectroscopic analyses, including HRESIMS, IR, optical rotation, 1 D- and 2 D-NMR spectra. The possible biosynthetic pathway is deduced and may be attributed to the metabolic activity of microbial symbionts in M. charantia L. Compound 1 was evaluated for anti-inflammatory activity against LPS-induced NO production in RAW 264.7 cells and anti-proliferative activity against four cancer cell lines, including HEp-2, MCF-7, Hep-G2, and WiDr. Compound 1 showed moderate anti-inflammatory activity with an IC50 value of 18.5 ± 0.4 µg/mL and weak anti-proliferative activity against MCF-7, HEp-2, Hep-G2, and WiDr with IC50 values of >40, 33.8 ± 0.6, 31.0 ± 0.7, and 27.0 ± 0.7 µM, respectively.

14.
Orthopedics ; 46(2): 103-107, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36343631

RESUMO

For Bennett fractures with tiny avulsion fragments, healing may be jeopardized owing to limited fracture contact surface if displacement of reduced fracture junctions occurs. This study aimed to assess the efficacy of treating Bennett fractures with tiny avulsion fragments using percutaneous small-diameter K-wires for tiny fragment fixation and thumb carpometacarpal (CMC) joint transfixation. From 2011 to 2019, we retrospectively enrolled patients with Gedda type 3 Bennett fractures who underwent operation with K-wire percutaneous pinning for the tiny fragment and CMC joint. We enrolled a total of 13 patients (13 fractures) with a mean age of 26.9 years (range, 18-42 years) at operation and a mean follow-up time of 17.9 months (range, 12-34 months). At the final follow-up, the shortened Disabilities of the Arm, Shoulder and Hand Questionnaire mean score was 4.7, and the visual analog scale score for pain during activity was 0.7. Mean grip strength was 34.7 kg (97.7% of the value on the unaffected side). Mean pinch strength was 5.4 kg (90.5% of the value on the unaffected side). Mean first web opening angle was 66.2° (96.6% of the value on the unaffected side). There were no changes in gap and step-off during the healing process and no osteoarthritic changes in the thumb CMC joint at the final follow-up. For Bennett fractures with tiny avulsion fragment, percutaneous treatment with small-diameter K-wires for fragment fixation and thumb CMC joint transfixation provides a viable alternative with fracture healing and good functional outcomes. [Orthopedics. 2023;46(2):103-107.].


Assuntos
Fraturas Ósseas , Luxações Articulares , Traumatismos do Punho , Humanos , Adulto , Fixação Interna de Fraturas , Estudos Retrospectivos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Luxações Articulares/cirurgia
15.
Tech Hand Up Extrem Surg ; 27(1): 45-48, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35993564

RESUMO

Open reduction internal fixation with plate fixation is commonly used in treating metacarpal fractures to facilitate early rehabilitation. However, it is sometimes challenging to maintain a satisfactory 3-dimensional alignment during the plating process. We present a method using a temporary centrally placed intramedullary k-wire to maintain a fundamental stability for reduction of metacarpal fractures. This method facilitates the plating process and simplifies the open reduction internal fixation of the metacarpal fractures.


Assuntos
Fixação Intramedular de Fraturas , Fraturas Ósseas , Traumatismos da Mão , Ossos Metacarpais , Humanos , Ossos Metacarpais/cirurgia , Fraturas Ósseas/cirurgia , Fixação Interna de Fraturas/métodos , Fios Ortopédicos , Fixação Intramedular de Fraturas/métodos
16.
Pharmaceuticals (Basel) ; 15(10)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36297330

RESUMO

Hybrid natural products produced via mixed biosynthetic pathways are unique and often surprise one with unexpected medicinal properties in addition to their fascinating structural complexity/diversity. In view of chemical structures, hybridization is a way of diversifying natural products usually through dimerization of two similar or dissimilar subcomponents through a C-C or N-C covalent linkage. Here, we report four structurally attractive diterpene-alkaloid conjugates polyalongarins A-D (1-4), clerodane-containing aporphine and proaporphine alkaloids, the first of its kind from the barks of Taiwanese Polyalthia longifolia (Sonn.) Thwaites var. pendula. In addition to conventional spectroscopic analysis, single crystal X-ray crystallography was employed to determine the chemical structures and stereo-configurations of 1. Compounds 1-4 were subsequently subjected to in vitro antiviral examination against DENV2 by evaluating the expression level of the NS2B protein in DENV2-infected Huh-7 cells. These compounds display encouraging anti-DENV2 activity with superb EC50 (2.8-6.4 µM) and CC50 values (50.4-200 µM). The inhibitory mechanism of 1-4 on NS2B was further explored drawing on in-silico molecular docking analysis. Based on calculated binding affinities and predicted interactions between the functional groups of 1-4 and the allosteric-site residues of the DENV2 NS2B-NS3 protease, our analysis concludes that the clerodane-aporphine/proaporphine-type hybrids are novel and effective DENV NS2B-NS3 protease inhibitors.

17.
Front Chem ; 10: 1003356, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36186589

RESUMO

Mesona procumbens Hemsley is a plant conventionally processed to provide popular food materials and herbal medicines in Asia. In this study, six triterpene acids, including five new ones (mesonaic acids D-H, 1-5), and one proximadiol-type sesquiterpene (7) were isolated from the methanolic extract of the air-dried M. procumbens. Chemical structures of 1‒7 were established by spectroscopic methods, especially 2D NMR techniques (1H-1H COSY, HSQC, HMBC, and NOESY) and HRESIMS. Concerning their biological activities, compounds 1, 2, 6, and 7 were examined manifesting high inhibition toward the pro-inflammatory NO production with EC50 values ranging from 12.88 to 21.21 µM, outrunning the positive control quercetin (24.12 µM). The mesoeudesmol B (7) identified from M. procumbens is the very first example, which exhibited high anti-inflammatory activity diminishing the level of the lipopolysaccharide-induced NO in RAW264.7 macrophage cells, thereby suppressing the secretion of pro-inflammatory cytokines TNF-α and IL-6 and the level of two critical downstream inflammatory mediators iNOS and COX-2.

18.
Appl Environ Microbiol ; 88(17): e0080622, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36000868

RESUMO

Albofungin, a hexacyclic aromatic natural product, exhibits broad-spectrum antimicrobial activity. Its biosynthesis, regulation, and resistance remain elusive. Here, we report the albofungin (abf) biosynthetic gene cluster (BGC) from its producing strain Streptomyces tumemacerans JCM5050. The nascent abf BGC encodes 70 putative genes, including regulators, transporters, type II polyketide synthases (PKSs), oxidoreductase, and tailoring enzymes. To validate the intactness and functionality of the BGC, we developed an Escherichia coli-Streptomyces shuttle bacterial artificial chromosome system, whereby the abf BGC was integrated into the genome of a nonproducing host via heterologous conjugation, wherefrom albofungin can be produced, confirming that the BGC is in effect. We then delimited the boundaries of the BGC by means of in vitro CRISPR-Cas9 DNA editing, concluding a minimal but essential 60-kb abf BGC ranging from orfL to abf58. The orfA gene encoding a reduced flavin adenine dinucleotide (FADH2)-dependent halogenase was examined and is capable of transforming albofungin to halogen-substituted congeners in vivo and in vitro. The orfL gene encoding a transporter was examined in vivo. The presence/absence of orfA or orfL demonstrated that the MIC of albofungin is subject to alteration when an extracellular polysaccharide intercellular adhesin was formed. Despite that halogenation of albofungin somewhat increases binding affinity to transglycosylase (TGase), albofungin with/without a halogen substituent manifests similar in vitro antimicrobial activity. Halogenation, however, limits overall dissemination and effectiveness given a high secretion rate, weak membrane permeability, and high hydrophobicity of the resulting products, whereby the functions of orfA and orfL are correlated with drug detoxification/resistance for the first time. IMPORTANCE Albofungin, a natural product produced from Streptomycetes, exhibits bioactivities against bacteria, fungi, and tumor cells. The biosynthetic logic, regulations, and resistance of albofungin remain yet to be addressed. Herein, the minimal albofungin (abf) biosynthetic gene cluster (BGC) from the producing strain Streptomyces tumemacerans JCM5050 was precisely delimited using the Escherichia coli-Streptomyces shuttle bacterial artificial chromosome system, of which the gene essentiality was established in vivo and in vitro. Next, we characterized two genes orfA and orfL encoded in the abf BGC, which act as a reduced flavin adenine dinucleotide (FADH2)-dependent halogenase and an albofungin-congeners transporter, respectively. While each testing microorganism exhibited different sensitivities to albofungins, the MIC values of albofungins against testing strains with/without orfA and/or orfL were subject to considerable changes. Halogen-substituted albofungins mediated by OrfA manifested overall compromised dissemination and effectiveness, revealing for the first time that two functionally distinct proteins OrfA and OrfL are associated together, exerting a novel "belt and braces" mechanism in antimicrobial detoxification/resistance.


Assuntos
Anti-Infecciosos , Produtos Biológicos , Streptomyces , Anti-Infecciosos/metabolismo , Produtos Biológicos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Flavina-Adenina Dinucleotídeo/metabolismo , Halogenação , Halogênios/metabolismo , Família Multigênica , Streptomyces/genética , Xantenos
19.
J Hand Surg Eur Vol ; 47(9): 935-943, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35579202

RESUMO

This retrospective study reviewed 28 patients, aged 10 to 17 years, who underwent corrective osteotomy for malunion of the proximal phalangeal distal condyles at a mean of 9 weeks (range 2-52) from injury. There were 19 patients treated with K-wire and nine patients with locking plates. The two groups were comparable for trauma mechanism, fracture type, time delay from injury and the type of initial treatment. The K-wire group had a shorter duration of operation and shorter time to union than the plating group. For both groups, postoperative radiographs showed significant correction, which remained unchanged until the final follow-up (minimum 12 months), although greater residual coronal angulation was found in the K-wire group. The outcomes in 17 of the 28 patients were graded as excellent or good according to the Al-Qattan classification, with no difference between the groups. The complication rate was also similar between the groups, while the locking plate group had a higher rate of secondary surgery.Level of evidence: III.


Assuntos
Placas Ósseas , Osteotomia , Adolescente , Osso e Ossos , Fixação Interna de Fraturas , Humanos , Estudos Retrospectivos , Resultado do Tratamento
20.
Food Chem X ; 14: 100286, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35330883

RESUMO

Four novel triterpene glycosides, taimordisins A-D (1-4), were discovered from fresh fruits of Taiwanese Momordica charantia. The chemical framework and relative stereochemistry of these four natural products were isolated, purified, and determined by using various separation and spectroscopy techniques. Each of them features a unique bicyclic-fused or trifuso-centro-fused ring system. Notably, 1 and 2 are cucurbitane-based compounds possessing a new C-24 and C-2″ carbon-carbon linkage with 5-hydroxy-2-(hydroxymethyl)tetrahydro-4H-pyran-4-one and 6-(hydroxymethyl)tetrahydro-4H-pyran-3,4,4-triol units, respectively, and represented an unprecedented molecular skeleton. In terms of biosynthesis, they all originate from a common precursor 3-hydroxycucurbita-5,24-dien-19-al-7,23-di-O-ß-glucopyranoside. Of two sugar moieties, the one at 23-O-ß-glucopyranoside grants each individual congener uniqueness likely through microbial symbiont-mediated intramolecular transformation into two major types of furo[2,3-b]pyranone and furo[3,2-c]pyranone derivatives. These new products possess desirable anti-inflammatory biological activities in addition to being generally regarded as safe.

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