Comtrifosides A and B, two new triterpenoid saponins from the leaves of Combretum trifoliatum.

The phytochemical composition of the Combretum trifoliatum leaves was studied for the first time. Two new triterpenoid saponins, named comtrifoside A (1) and comtrifoside B (2), together with two other saponins (3-4) were purified by variously chromatographic techniques. For the first time, compound 3 was informed from the Combretum genus, as well as all of the isolated compounds (1-4) were reported from C. trifoliatum. The chemical structures of them were clearly characterised using extensive UV-VIS, IR, HRMS-ESI, and NMR experimental data. The in vitro anti-inflammatory activities of 1 & 2 were examined against NO overproduction in LPS activation of RAW264.7.

Tinctoric acid A-B, two new hopan-type triterpenoids from the Vietnamese lichen, Parmotrema tinctorum (Despr. ex Nyl.) hale with α-glucosidase inhibitory activity.

Two new hopan-type triterpenoids, namely tinctoric acid A-B (1-2), were isolated from the lichen Parmotrema tinctorum (Despr. ex Nyl.) Hale. Their structures were elucidated by extensive spectroscopic analyses (1D and 2D NMR). The absolute configuration at C-22 of 1 was established through DP4 probability. Compounds 1-2 were evaluated for their inhibitory activity against α-glucosidase and found to be more potent than those of positive control (acarbose, IC50 168 µM) with values IC50 74.7 and 98.2 µM, respectively. Both of these compounds interacted well with enzyme α-glucosidase MAL32 through H-bonds and hydrophobic interaction.

Bio-guided isolation of alpha-glucosidase inhibitory compounds from Vietnamese Garcinia schomburgkiana fruits: in vitro and in silico studies.

Garcinia schomburgkiana is an edible tree widely distributed in the southern region of Vietnam. Little is known about the alpha-glucosidase inhibition of the Vietnamese Garcinia schomburgkiana. The aim of the current study was to explore the anti-diabetic potential of G. schomburgkiana fruits. All the fractions of G. schomburgkiana were evaluated for alpha-glucosidase inhibition, followed by bioassay-guided isolation. A new compound, epi-guttiferone Q (1), together with ten known compounds, guttiferones I-K (2-3), hypersampsone I (4), sampsonione D (5), sampsonione H (6), ß-mangostin (7), α-mangostin (8), 9-hydroxycalabaxanthone (9), and fuscaxanthone (10), were isolated and structurally elucidated. The structure of the new metabolite 1 was confirmed through 1D and 2D NMR spectroscopy, and MS analysis. To the best of our knowledge, the metabolites (except 3) have not been isolated from this plant previously. All isolated compounds were evaluated for their alpha-glucosidase inhibition. Compounds 1-6 showed potent activity with IC50 values ranging from 16.2 to 130.6 µM. Compound 2 was further selected for a kinetic study. The result indicated that it was a competitive type. Additionally, in silico docking was employed to predict the binding mechanism of 1-2 and 4-6 in the active site of alpha-glucosidase, suggesting their potential as promising anti-diabetic compounds. Molecular dynamic simulation was also applied to 1 to better understand its inhibitory mechanism.

Tinctorin, a new spiroterpenoid from the lichen Parmotrema tinctorum (Despr. ex Nyl.) Hale growing in Vietnam.

A new spiroterpenoid, namely tinctorin (1), along with one known compound, norreticulatin (2), were isolated from the lichen Parmotrema tinctorum (Despr. ex Nyl.) Hale. Their structures were elucidated by extensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. The absolute configuration of 2 was established for the first time. Compound 1 was evaluated for its inhibitory activity against α-glucosidase and found to be inactive.

New Halogenated Flavonoids from Adenosma bracteosum and Vitex negundo and Their α-Glucosidase Inhibition.

Adenosma bracteosum and Vitex negundo are natural sources of methoxylated flavonoids. Little is known about the α-glucosidase inhibition of multi-methoxylated flavonoid derivatives. Eighteen natural flavonoids were isolated from A. bracteosum and V. negundo. Seven halogenated derivatives were synthesized. Their chemical structures were elucidated by extensive NMR analysis and high-resolution mass spectroscopy as well as comparisons in literature. All compounds were evaluated for their α-glucosidase inhibition. Most compounds showed good activity with IC50 values ranging from 16.7 to 421.8 µM. 6,8-Dibromocatechin was the most active compound with an IC50 value of 16.7 µM. A molecular docking study was conducted, indicating that those compounds are potent α-glucosidase inhibitors.

Glacial changes in sea level modulated millennial-scale variability of Southeast Asian autumn monsoon rainfall.

Most paleoclimate studies of Mainland Southeast Asia hydroclimate focus on the summer monsoon, with few studies investigating rainfall in other seasons. Here, we present a multiproxy stalagmite record (45,000 to 4,000 years) from central Vietnam, a region that receives most of its annual rainfall in autumn (September-November). We find evidence of a prolonged dry period spanning the last glacial maximum that is punctuated by an abrupt shift to wetter conditions during the deglaciation at ~14 ka. Paired with climate model simulations, we show that sea-level change drives autumn monsoon rainfall variability on glacial-orbital timescales. Consistent with the dry signal in the stalagmite record, climate model simulations reveal that lower glacial sea level exposes land in the Gulf of Tonkin and along the South China Shelf, reducing convection and moisture delivery to central Vietnam. When sea level rises and these landmasses flood at ~14 ka, moisture delivery to central Vietnam increases, causing an abrupt shift from dry to wet conditions. On millennial timescales, we find signatures of well-known Heinrich Stadials (HS) (dry conditions) and Dansgaard-Oeschger Events (wet conditions). Model simulations show that during the dry HS, changes in sea surface temperature related to meltwater forcing cause the formation of an anomalous anticyclone in the Western Pacific, which advects dry air across central Vietnam, decreasing autumn rainfall. Notably, sea level modulates the magnitude of millennial-scale dry and wet phases by muting dry events and enhancing wet events during periods of low sea level, highlighting the importance of this mechanism to autumn monsoon variability.

A New Carvotacetone Derivative from the Aerial Part of Sphaeranthus africanus.

Sphaeranthus africanus L. is native in Vietnam. Little is known about α-glucosidase inhibition of Sphaeranthus africanus and its isolated compounds. A bioactive-guided isolation was applied to the Vietnamese Sphaeranthus africanus to find α-glucosidase inhibitory components. Eight compounds were detected and structurally elucidated. They are 3-angeloyloxy-5-[2'',3''-epoxy-2''-methylbutanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[3''-chloro-2''-hydroxy-2''-methylbutanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[2''R,3''R-dihydroxy-2''-methyl-butanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[2''S,3''R-dihydroxy-2''-methylbutanoyloxy]-7-hydroxycarvotacetone, 3-angeloyloxy-5-[2''S,3''S-dihydroxy-2''-methylbutanoyloxy]-7-hydroxycarvotacetone, 5-angeloyloxy-7-hydroxy-3-tigloyloxycarvotacetone, 3-O-methylquercetin, and chrysosplenol D. Their chemical structures were elucidated by extensive 1D and 2D NMR analysis and high-resolution mass spectroscopy as well as comparisons in literature. 3-Angeloyloxy-5-[2''S,3''S-dihydroxy-2''-methylbutanoyloxy]-7-hydroxycarvotacetone is a new compound. Isolated compounds were evaluated for the α-glucosidase inhibition. Isolated compounds showed moderate activity with IC50 values ranging from 128.9-274.3 µM while others are weak. A molecular docking study was conducted, indicating that isolated compounds are potent α-glucosidase inhibitory compounds.

Caprini assessment utilization and impact on patient safety in gynecologic surgery.

PURPOSE: Postoperative venous thromboembolism (VTE) can potentially be associated with significant morbidity, mortality, and healthcare costs. The aim of this study was to determine the utilization of Caprini guideline indicated VTE in elective gynecologic surgery patients and its impact on postoperative VTE and bleeding complications. METHODS: This was a retrospective cohort study of elective gynecologic surgical procedures performed between January 1, 2016, and May 31, 2021. Two study cohorts were generated: (1) those who received and (2) those who did not receive VTE prophylaxis based on Caprini score risk stratification. Outcome measures were then compared between the study cohorts and included the development of a VTE up to 90-days postoperatively. Secondary outcome measures included postoperative bleeding events. RESULTS: A total of 5471 patients met inclusion criteria and the incidence of VTE up to 90 days postoperatively was 1.04%. Overall, 29.6% of gynecologic surgery patients received Caprini score-based guideline VTE prophylaxis. 39.2% of patients that met high-risk VTE criteria (Caprini > 5) received appropriate Caprini score-based prophylaxis. In multivariate regression analysis, the American Society of Anesthesiologists (ASA) score (OR 2.37, CI 1.27-4.45, p < 0.0001) and Caprini score (OR 1.13, CI 1.03-1.24, p = 0.008) predicted postoperatively VTE occurrence. Increasing Charlson comorbidity score (OR 1.39, CI 1.31-1.47, P < 0.001) ASA score (OR 1.36, CI 1.19-1.55, P < 0.001) and Caprini score (OR 1.10, CI 1.08-1.13, P < 0.001) were associated with increased odds of receiving appropriate inpatient VTE prophylaxis. CONCLUSION: While the overall incidence of VTE was low in this cohort, enhanced adherence to risk-based practice guidelines may provide more patient benefit than harm to postoperative gynecologic patients.

Communication Training Helps to Reduce Burnout During COVID-19 Pandemic.

Objective: To determine the effectiveness of communication training and its impact on burnout among healthcare providers (physicians, physician assistants, nurse practitioners), in the setting of the COVID-19 pandemic. Methods: To evaluate the effectiveness of communication training on burnout during the COVID-19 pandemic, healthcare providers participating in a Communication in Healthcare (CIH) module between October 31, 2019, through February 20, 2020, were identified using a scanned sign-in sheet. A 3-question online survey regarding the utilization of communication skills during the COVID-19 pandemic was sent via email. An ordinal scale was used to rate the effectiveness of the training on subsequent burnout and work satisfaction during the pandemic. Results: Of the 98 surveys distributed via email, a total of 33 participants completed the survey. Seventy-three percent of respondents agreed that communication training helped prevent burnout, and 39% strongly agreed that the modules improved work satisfaction. Conclusion: Our study found communication training was effective in reducing burnout in healthcare providers, in the setting of the COVID-19 pandemic. The participants felt the communication tools learned from the training modules were useful in improving work satisfaction and communication with patients during the pandemic.

Indicuen, a new hopane from Parmotrema indicum Hale growing in Vietnam.

One new hopane-type triterpene, indicuen (1), along with eight known compounds (2-9) were isolated from the n-hexane extract of the lichen Parmotrema indicum Hale. The chemical structures of isolated compounds were identified by interpretation of their spectroscopic data (1D, 2D NMR and HRESIMS) combined with DFT-NMR chemical shift calculations and subsequent assignment of DP4+ probabilities and by comparison with the literature. Indicuen represents for a rare hopane bearing a 1-carboxyethyl substituent at C-21 in lichens. Compounds 1-3 and 5-8 were evaluated for α-glucosidase inhibition and cytotoxicity against K562 and HepG2 cancer cell lines. Compounds 1, 5 and 7 exhibited moderate α-glucosidase inhibition with IC50 values of 201.1, 156.3 and 187.4 µM, respectively. Compound 1 also showed weak cytotoxicity toward K562 cell line while others showed no activity.

Anonazepine, a new alkaloid from the leaves of Annona muricata (Annonaceae).

From the CHCl3-soluble extract of Annona muricata L. (Annonaceae) leaves, one new 3-benzazepine-type alkaloid, anonazepine (1), and four known aporphine-type alkaloids, (+)-laurotetanine (2), (+)-norglaucine (3), (-)-xylopine (4), and lanuginosine (5), were isolated. Except for (-)-xylopine (4), these remaining known alkaloids were first reported in A. muricata. The structures of the isolated alkaloids were established by 1D and 2D NMR spectroscopy and MS, as well as comparison with literature data. The new 3-benzazepine-type alkaloid existed in an inseparable mixture of two equilibrium conformers. Its absolute configuration was determined based on comparing their experimental and calculated ECD data. The anti-inflammatory activity of the isolated alkaloids was investigated, but none of the alkaloids showed a significant result.

Supercritical CO2 assisted extraction of essential oil and naringin from Citrus grandis peel: in vitro antimicrobial activity and docking study.

The extraction of bioactive compounds, including essential oils and flavonoids, using organic solvents is a significant environmental concern. In this work, waste C. grandis peel was the ingredient used to extract essential oil and naringin by conducting a supercritical CO2 technique with a two stage process. In the first stage, the extraction with only supercritical CO2 solvent showed a significant enhancement of the d-limonene component, up to 95.66% compared with the hydro-distillation extraction (87.60%). The extraction of naringin using supercritical CO2 and ethanol as a co-solvent was done in the second stage of the process, followed by evaluating in vitro antimicrobial activity of both the essential oil and naringin. The essential oil indicated significant activity against M. catarrhalis (0.25 mg ml-1), S. pyogenes (1.0 mg ml-1), S. pneumoniae (1.0 mg ml-1). Whilst naringin gave good inhibition towards all tested microbial strains with MIC values in the range of 6.25-25.0 µM. In particular, naringin exhibited high antifungal activity against T. rubrum, T. mentagrophytes, and M. gypseum. The molecular docking study also confirmed that d-limonene inhibited bacterium M. catarrhalis well and that naringin possessed potential ligand interactions that proved the inhibition effective against fungi. Molecular dynamics simulations of naringin demonstrated the best docking model using Gromacs during simulation up to 100 ns to explore the stability of the complex naringin and crystal structure of enzyme 2VF5: PDB.

α-Glucosidase Inhibitory Cycloartanes from the Vietnamese Combretum quadrangulare.

Leaves of Combretum quadrangulare Kurz showed potent α-glucosidase inhibition. Two new cycloartane-type triterpenes, combretic acids D and E were isolated from the bioactive fraction. The chemical structures were determined using NMR and MS methods. Combretic acid D represents for the first cycloartane having a dihydrofuran ring in the side chain. Combretic acids D and E showed significant α-glucosidase inhibition, with IC50 values of 13.9 and 30.7 µM, respectively. Combretic acid D was determined to be a non-competitive type in the kinetic study. The docking study in combination with dynamic simulations of this compound provided the molecular understanding of α-glucosidase inhibition.

Surgical Science-Simbionix Robotic Hysterectomy Simulator: Validating a New Tool.

STUDY OBJECTIVE: To gather validity evidence for and determine acceptability of Surgical Science-Simbionix Hysterectomy Modules for the DaVinci Xi console simulation system (software; 3D Systems by Simbionix [now Surgical Science-Simbionix], Littleton, CO, and hardware; Intuitive Surgical, Inc., Sunnyvale, CA) and evaluate performance benchmarks between novice and experienced or expert surgeons. DESIGN: Prospective education study (Messick validity framework). SETTING: Multicenter, academic medical institutions. PARTICIPANTS: Residents, fellows, and faculty in obstetrics and gynecology were invited to participate at 3 institutions. Participants were categorized by experience level: fewer than 10 hysterectomies (novice), 10 to 50 hysterectomies (experienced), and more than 50 hysterectomies (expert). A total of 10 novice, 10 experienced, and 14 expert surgeons were included. INTERVENTIONS: Participants completed 4 simulator modules (ureter identification, bladder flap development, colpotomy, complete hysterectomy) and a qualitative survey. Simulator recordings were reviewed in duplicate by educators in minimally invasive gynecologic surgery using the Modified Global Evaluative Assessment of Robotic Skills (GEARS) rating scale. MEASUREMENTS AND MAIN RESULTS: Most participants felt that the simulator realistically simulated robotic hysterectomy (64.7%) and that feedback provided by the simulator was as or more helpful than feedback from previous simulators (88.2%) but less helpful than feedback provided in the operating room (73.5%). Participants felt that this simulator would be helpful for teaching junior residents. Simulator-generated metrics correlated with GEARS performance for the bladder flap and ureter identification modules in multiple domains including total movements and total time for completion. GEARS performance for the bladder flap module correlated with experience level (novice vs experienced/expert) in the domains of interest and total score but did not consistently correlate for the other procedural modules. Performance benchmarks were evaluated for the bladder flap module for each GEARS domain and total score. CONCLUSION: The modules were well received by participants of all experience levels. Individual simulation modules appear to better discriminate between novice and experienced/expert users than overall simulator performance. Based on these data and participant feedback, the use of individual modules in early residency education may be helpful for providing feedback and may ultimately serve as 1 component of determining readiness to perform robotic hysterectomy.

Alpha-glucosidase inhibitors from Nervilia concolor, Tecoma stans, and Bouea macrophylla.

Tecoma stans (L.) Juss. Ex Kunth is widely used in folk medicine. In ethnomedicine, it is applied as a cardioprotective, hepatoprotective, antiarthritic, antinociceptive, anti-inflammatory, and antimicrobial. The aqueous extract is considered antidiabetic, and is used as a traditional remedy in Mexico. More than 120 chemical constituents have been identified in its leaves, barks, and roots. However, less is known about the phytochemical properties of T. stans flower extracts. The herbal plant Nervilia concolor (Blume) Schltr. is native to Vietnam, and is used in traditional Chinese medicine to treat diseases such as bronchitis, stomatitis, acute pneumonia, and laryngitis. Only two previous reports have addressed the chemical content of this plant. Bouea macrophylla Griff., commonly known as marian plum or plum mango, is a tropical plant that is used to treat a range of illnesses. Phytochemical analysis of B. macrophylla suggests the presence of volatile components and flavonoids. However, existing data have been obtained from screening without isolation. As part of our ongoing search for alpha-glucosidase inhibitors from Vietnamese medicinal plants, we conducted bioactive-guided isolation of the whole plant N. concolor, the flowers of T. stans, and the leaves of B. macrophylla. We isolated and structurally elucidated five known compounds from T. stans: ursolic acid (TS1), 3-oxours-12-en-28-oic acid (TS2), chrysoeriol (TS3), ferulic acid (TS4), and tecomine (TS5). Three known compounds were isolated from Nervilia concolor: astragalin (NC1), isoquercitrin (NC2), and caffeic acid (NC3). From B. macrophylla, betullinic acid (BM1), methyl gallate (BM2), and 3-O-galloyl gallic acid methyl ester (BM3) were isolated. All compounds showed promising alpha-glucosidase inhibition, with IC50 values ranging from 1.4 to 143.3 µM. The kinetics of enzyme inhibition showed BM3 to be a competitive-type inhibitor. An in silico molecular docking model confirmed that compounds NC1, NC2, and BM3 were potential inhibitors of the α-glucosidase enzyme. Molecular dynamics simulations were carried out with compound BM3 demonstrating the best docking model during simulation up to 100 ns to explore the stability of the complex ligand-protein.

Impact of robotic single and dual console systems in the training of minimally invasive gynecology surgery (MIGS) fellows.

The advantages of dual console use in robotic surgical education have not been described. The aims of this study are to compare fellow console time, surgical steps performed, and surgical takeovers between attending and fellow surgeons using dual versus single console robotic systems. Participants included minimally invasive gynecologic surgery (MIGS) fellows (N = 3) and subspecialty trained gynecologic surgeons (N = 5). Prospective data were obtained on 126 patients (N = 77 single console, N = 49 dual console) undergoing robotic hysterectomy. Variables included demographics, surgical characteristics (fellow, month of fellowship, attending surgeon, concomitant oophorectomy, additional surgical procedures, estimated blood loss, specimen weight), and outcomes (console time, docking time, console time/docking time ratio, total case time, number of surgical steps performed by the fellow, number of surgical takeovers, complications). After controlling for potential confounders, fellows spent a mean of 25.8 min longer (P < 0.001) at the console in dual console operations compared to single. Dual console surgeries had a greater number of steps performed by the fellow (OR[> 5 steps]: 3.37, P = 0.009), a higher console time/docking time ratio (P < 0.001), and more surgical takeovers between fellow and attending (OR [> 1 takeover]: 3.53, P < 0.001). There were no significant differences between the two groups regarding docking time (P = 0.15), case time (P = 0.79), or complications (P = 0.30). Our findings suggest dual console robotic training provide fellows the opportunity for more "hands-on" experience with longer console time, higher number of surgical steps performed, and added interaction with the attending surgeon when compared with single console training. These surgical metrics provide objectivity in competency-based robotic training without increasing the complications or surgical time.

Parmosidone K, a new meta-depsidone from the lichen Parmotrema tsavoense.

Further phytochemical investigation on P. tsavoense led to one new meta-depsidone, parmosidone K together with one known compound, barbatic acid. Their structures were determined by 1D and 2D NMR analysis, high resolution mass spectroscopy, and comparison their NMR data with those reported in literatures. Parmosidone K was evaluated for α-glucosidase inhibition and revealed the powerful activity with IC50 value of 3.12 µM.

Ricicomin A, a new alkaloid from the leaves of Ricinus communis Linn.

From the leaves of Ricinus communis Linn., one new alkaloid, named ricicomin A (1) together with three known ones, ricinine (2), N-demethylricinine (3) and 4-[2-formyl-5-(methoxymethyl)-1H-pyrrol-1-yl]butanoic acid (4) were justified by repeated chromatographic methods. Their structures were determined by comprehensive IR, HR-ESI-MS and NMR analyses. Compound 4 was identified for the first time from the genus Ricinus. DFT-NMR chemical shift calculations and subsequent DP4+ probability methods were applied to confirm the chemical structure of 1. Compounds 1-3 did not display cytotoxic effect against three human cancer cell lines (MCF-7, HepG2 and HeLa) using SRB assay.