Discovery of new triterpene glycosides from Dendrobium officinale with their α-glucosidase and α-amylase inhibitory activity.

In this study, seven new pentacyclic triterpene glycosides, named dendrocinaosides A-G (1-7), and six known ones (8-13) were isolated from the whole plants of Dendrobium officinale. Their structures were determined by analyses of HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1-4, 8, and 9 potentially inhibited α-glucosidase and α-amylase activities with the IC50 values ranging from 31.3 ± 2.2 to 42.4 ± 2.5 µM for anti α-glucosidase and from 36.5 ± 1.8 to 56.4 ± 2.0 µM for anti α-amylase activities, respectively, which were lower than that of the positive control, acarbose, showing IC50 values of 47.1 ± 1.4 µM for anti α-glucosidase and 145.7 ± 2.2 µM for anti α-amylase.

Rare Cause of Gastrointestinal Bleeding: A Case Report of Pancreatic Arteriovenous Malformation.

BACKGROUND Arteriovenous malformation is an unusual cause of gastrointestinal bleeding, particularly in the pancreas. A definitive treatment strategy is not yet established. CASE REPORT We present the case of a 37-year-old man with underlying hypertension and no significant family history who presented with a 3-month history of intermittent epigastric pains and unintentional weight loss of 5 kg in 2 months. The upper endoscopy showed a large duodenal ulcer, which was uncontrolled with a standard dose of proton pump inhibitors. An abdominal computed tomography scan with contrast was indicated and revealed an enhanced mass of 2.5×3.5×4 cm in size, located on the second and third parts of the duodenum and head of the pancreas, indicating an arteriovenous malformation. On day 10 of hospitalization, the patient suddenly had melena and a drop of hemoglobin level to 5.6 g/dL; angiography intervention was successful to control the bleeding. However, gastrointestinal bleeding recurred after 2 weeks, and the patient successfully underwent a Whipple procedure. CONCLUSIONS The diagnosis and therapeutic management of arteriovenous malformations are uniquely challenging; therefore, pancreatic arteriovenous malformations should be listed on the differential diagnosis, particularly in those cases with non-healing and large duodenal ulcers. Otherwise, early imaging modalities should be performed to confirm the diagnosis. In particular, angiography can temporarily control bleeding before proceeding with more definitive therapy.

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.

The first maternal genetic study of hunter-gatherers from Vietnam.

The current limitation of ancient DNA data from Vietnam led to the controversy surrounding the prehistory of people in this region. The combination of high heat and humidity damaged ancient bones that challenged the study of human evolution, especially when using DNA as study materials. So far, only 4 k years of history have been recorded despite the 65 k years of history of anatomically modern human occupations in Vietnam. Here we report, to our knowledge, the oldest mitogenomes of two hunter-gatherers from Vietnam. We extracted DNA from the femurs of two individuals aged 6.2 k cal BP from the Con Co Ngua (CCN) site in Thanh Hoa, Vietnam. This archeological site is the largest cemetery of the hunter-gatherer population in Southeast Asia (SEA) that was discovered, but their genetics have not been explored until the present. We indicated that the CCN haplotype belongs to a rare haplogroup that was not detected in any present-day Vietnamese individuals. Further matrilineal analysis on CCN mitogenomes showed a close relationship with ancient farmers and present-day populations in SEA. The mitogenomes of hunter-gatherers from Vietnam debate the "two layers" model of peopling history in SEA and provide an alternative solution for studying challenging ancient human samples from Vietnam.

The Influence of Protein Charge and Molecular Weight on the Affinity of Aptamers.

Aptamers offer several advantages over antibodies. However, to ensure high affinity and specificity, a better understanding of the interactions between the nucleic-acid-based aptamers and their targets is mandatory. Therefore, we investigated the influence of two physical properties of proteins-molecular mass and charge-on the affinity of nucleic-acid-based aptamers. For this purpose, first, the affinity of two random oligonucleotides towards twelve proteins was determined. No binding was observed for proteins with a negative net charge towards the two oligonucleotides, while up to nanomolar affinity was determined for positively charged proteins with a high pI value. Second, a literature analysis comprising 369 aptamer-peptide/protein pairs was performed. The dataset included 296 different target peptides and proteins and is thus currently one of the largest databases for aptamers for proteins and peptides. The targets considered covered isoelectric points of 4.1-11.8 and a molecular weight range of 0.7-330 kDa, while the dissociation constants ranged from 50 fM to 29.5 µM. This also revealed a significant inverse correlation between the protein's isoelectric point and the affinity of aptamers. In contrast, no trend was observed between the affinity and the molecular weight of the target protein with either approach.

A sensorless anti-windup speed control approach to axial gap bearingless motors with nonlinear lumped mismatched disturbance observers.

In this paper, sensorless robust speed control with nonlinear lumped mismatched disturbance observers for a permanent magnet type axial gap bearingless motor (AGBM) is designed. Multistage anti-windup-based dynamic surface control combined with integral backstepping control is proposed to control the motor's axial displacement and rotor speed. The approach is against parameter uncertainties and external disturbances, improving steady-state accuracy, eliminating the derivative explosion phenomenon, no chattering problem, and reducing the magnitude of the control system when current saturation occurs. In addition, a novel nonlinear lumped mismatched disturbance observer is proposed to improve the approach under unmodeled dynamics and external disturbances. To obtain high-accuracy tracking control, the control system includes the robust controller combined with the disturbance observers and anticipatory activation of anti-windup (AW) compensation, which means the controller is more complex. Then, to design a sensorless robust speed control for the motor, the rotor position and speed observer require higher accuracy. High-gain back-EMF observer combined with an improved phase-locked loop is proposed to estimate rotor angular position and speed even when the motor speed is reversed. Overall stability of closed-loop system control, including a sensorless speed control approach for motors using back-EMF estimation combined with saturation of the currents and lumped disturbance observers, is mathematically proven. Finally, the simulation results under measurement noise show that the proposed control system are obtained the effectiveness, feasibility, and robustness.

The Complete Chloroplast Genome of An Ophiorrhiza baviensis Drake Species Reveals Its Molecular Structure, Comparative, and Phylogenetic Relationships.

Ophiorrhiza baviensis Drake, a flowering medical plant in the Rubiaceae, exists uncertainly within the Ophiorrhiza genus' evolutionary relationships. For the first time, the whole chloroplast (cp) genome of an O. baviensis Drake species was sequenced and annotated. Our findings demonstrate that the complete cp genome of O. baviensis is 154,770 bp in size, encoding a total of 128 genes, including 87 protein-coding genes, 8 rRNAs, and 33 tRNAs. A total of 59 SSRs were screened in the studied cp genome, along with six highly variable loci, which can be applied to generate significant molecular markers for the Ophiorrhiza genus. The comparative analysis of the O. baviensis cp genome with two published others of the Ophiorrhiza genus revealed a high similarity; however, there were some notable gene rearrangements in the O. densa plastome. The maximum likelihood phylogenetic trees were constructed based on the concatenation of the rps16 gene and the trnL-trnF intergenic spacer sequence, indicating a close relationship between the studied O. baviensis and other Ophiorrhiza. This study will provide a theoretical molecular basis for identifying O. baviensis Drake, as well as species of the Ophiorrhiza genus, and contribute to shedding light on the chloroplast genome evolution of Rubiaceae.

Community engagement in health systems interventions and research in conflict-affected countries: a scoping review of approaches.

BACKGROUND: Healthcare research, planning, and delivery with minimal community engagement can result in financial wastage, failure to meet objectives, and frustration in the communities that programmes are designed to help. Engaging communities - individual service-users and user groups - in the planning, delivery, and assessment of healthcare initiatives from inception promotes transparency, accountability, and 'ownership'. Health systems affected by conflict must try to ensure that interventions engage communities and do not exacerbate existing problems. Engaging communities in interventions and research on conflict-affected health systems is essential to begin addressing effects on service delivery and access. OBJECTIVE: This review aimed to identify and interrogate the literature on community engagement in health system interventions and research in conflict-affected settings. METHODS: We conducted a scoping review using Arksey & O'Malley's framework, synthesising the data descriptively. RESULTS: We included 19 of 2,355 potential sources identified. Each discussed at least one aspect of community engagement, predominantly participatory methods, in 12 conflict-affected countries. Major lessons included the importance of engaging community and religious leaders, as well as people of lower socioeconomic status, in both designing and delivering culturally acceptable healthcare; mobilising community members and involving them in programme delivery to increase acceptability; mediating between governments, armed groups and other organisations to increase the ability of healthcare providers to remain in post; giving community members spaces for feedback on healthcare provision, to provide communities with evidence that programmes and initiatives are working. CONCLUSION: Community engagement in identifying and setting priorities, decision-making, implementing, and evaluating potential solutions helps people share their views and encourages a sense of ownership and increases the likely success of healthcare interventions. However, engaging communities can be particularly difficult in conflict-affected settings, where priorities may not be easy to identify, and many other factors, such as safety, power relations, and entrenched inequalities, must be considered.

Operationalising Regional Cooperation for Infectious Disease Control: A Scoping Review of Regional Disease Control Bodies and Networks.

BACKGROUND: The rapid spread of the coronavirus disease 2019 (COVID-19) pandemic demonstrates the value of regional cooperation in infectious disease prevention and control. We explored the literature on regional infectious disease control bodies, to identify lessons, barriers and enablers to inform operationalisation of a regional infectious disease control body or network in southeast Asia. METHODS: We conducted a scoping review to examine existing literature on regional infectious disease control bodies and networks, and to identify lessons that can be learned that will be useful for operationalisation of a regional infectious disease control body such as the Association of Southeast Asian Nations (ASEAN) Center for Public Health Emergency and Emerging Diseases. RESULTS: Of the 57 articles included, 53 (93%) were in English, with two (3%) in Spanish and one (2%) each in Dutch and French. Most were commentaries or review articles describing programme initiatives. Sixteen (28%) publications focused on organisations in the Asian continent, with 14 (25%) focused on Africa, and 14 (25%) primarily focused on the European region. Key lessons focused on organisational factors, diagnosis and detection, human resources, communication, accreditation, funding, and sustainability. Enablers and constraints were consistent across regions/ organisations. A clear understanding of the regional context, budgets, cultural or language issues, staffing capacity and governmental priorities, is pivotal. An initial workshop inclusive of the various bodies involved in the design, implementation, monitoring or evaluation of programmes is essential. Clear governance structure, with individual responsibilities clear from the beginning, will reduce friction. Secure, long-term funding is also a key aspect of the success of any programme. CONCLUSION: Operationalisation of regional infectious disease bodies and networks is complicated, but with extensive groundwork, and focus on organisational factors, diagnosis and detection, human resources, communication, accreditation, funding, and sustainability, it is achievable. Ways to promote success are to include as many stakeholders as possible from the beginning, to ensure that context-specific factors are considered, and to encourage employees through capacity building and mentoring, to ensure they feel valued and reduce staff turnover.

Vietnam Association of Gastroenterology (VNAGE) consensus on the management of Helicobacter pylori infection.

Helicobacter pylori (H. pylori) infection is prevalent and has a rapidly increasing antibiotic resistance rate in Vietnam. Reinfection is quite common, and gastric carcinoma remains one of the most common malignancies, which is not uncommon to develop after successful eradication. The purpose of this consensus is to provide updated recommendations on the management of H. pylori infection in the country. The consensus panel consisted of 32 experts from 14 major universities and institutions in Vietnam who were invited to review the evidence and develop the statements using the Delphi method. The process followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The consensus level was defined as ≥80% for agreement on the proposed statements. Due to the limited availability of high-quality local evidence, this consensus was also based on high-quality evidence from international studies, especially those conducted in other populations in the Asia-Pacific region. The panel finally reached a consensus on 27 statements after two voting rounds, which consisted of four sections (1) indications for testing and selection of diagnostic tests (2), treatment regimens, (3) post-treatment confirmation of H. pylori status, and (4) reinfection prevention methods and follow-up after eradication. Important issues that require further evidence include studies on third-line regimens, strategies to prevent H. pylori reinfection, and post-eradication follow-up for precancerous gastric lesions. We hope this consensus will help guide the current clinical practice in Vietnam and promote multicenter studies in the country and international collaborations.

Late Discovering Spina Ventosa: A Case Report.

INTRODUCTION: Spina Ventosa is a rare condition that is easy to misdiagnose as other diseases. We present a case of late-diagnosed Spina Ventosa, which had not only the osteoarticular tuberculosis symptoms but also some severe symptoms, including pleural effusion, ascites, and anemia. By intensive treatment, our patient recovered completely. CASE REPORT: A 7-year-old boy was admitted with complaints of painless swelling of metacarpals, metatarsals, and phalanges of his hands and feet and a discharging sinus of the left toe. There was no family or past history of tuberculosis. His immunizations were up to date. General examination revealed that the child had pallor and was emaciated. No lymphadenopathy was detected. Investigations revealed hemoglobin: 74 g/l, and erythrocyte sedimentation rate (ESR) was 42 mm/hour. QuantiFERON-TB test was positive. The radiograph showed irregular swelling with sclerosis of the underlying bones. The right-hand x-ray showed cortical destruction, sclerosis, and cystic expansion or right second metacarpal. Chest x-ray indicated pleural effusion. Histopathological examination of specimen from the foot and lung and abdomen fluid confirmed tuberculosis. The child was treated with the first-line tuberculosis treatment regimen (Isoniazid, Rifampicin, Ethambutol, and Pyrazinamide) for two months, followed by Isoniazid, Rifampicin, and Pyrazinamide for a further four months. His lesions disappeared after six weeks of intensive treatment. CONCLUSION: A delay in diagnosis and treatment of tuberculosis can lead to systemic manifestations in multiple organs. Despite the delay in diagnosis, this child had a good outcome due to being treated promptly and adequately after the presentation.

Complete chloroplast genome of novel Adrinandra megaphylla Hu species: molecular structure, comparative and phylogenetic analysis.

Adrinandra megaphylla Hu is a medicinal plant belonging to the Adrinandra genus, which is well-known for its potential health benefits due to its bioactive compounds. This study aimed to assemble and annotate the chloroplast genome of A. megaphylla as well as compare it with previously published cp genomes within the Adrinandra genus. The chloroplast genome was reconstructed using de novo and reference-based assembly of paired-end reads generated by long-read sequencing of total genomic DNA. The size of the chloroplast genome was 156,298 bp, comprised a large single-copy (LSC) region of 85,688 bp, a small single-copy (SSC) region of 18,424 bp, and a pair of inverted repeats (IRa and IRb) of 26,093 bp each; and a total of 51 SSRs and 48 repeat structures were detected. The chloroplast genome includes a total of 131 functional genes, containing 86 protein-coding genes, 37 transfer RNA genes, and 8 ribosomal RNA genes. The A. megaphylla chloroplast genome indicated that gene content and structure are highly conserved. The phylogenetic reconstruction using complete cp sequences, matK and trnL genes from Pentaphylacaceae species exhibited a genetic relationship. Among them, matK sequence is a better candidate for phylogenetic resolution. This study is the first report for the chloroplast genome of the A. megaphylla.

Image formation by a biological curved mirror array of the fisheye in the deep-sea environment.

In this paper, we present the imaging formation process of the piecewise mirror eyes of the deep-sea spookfish, which has a strange combination of refractive and reflective eyes. The biological reflective eye structure is formulated to the curved surface's flat mirror array. Zemax is utilized to evaluate optical features such as the modulation transfer function, distortion, and imaging performances. However, the natural images are highly distorted, and the resolution is lower than expected. Therefore, we increase the number of piecewise mirrors of the fisheye to see higher quality images, which can be improved entirely by the mirror shapes. Finally, the fisheye's imaging analysis reveals the deep-sea creature's resolution limit and also shows the possibility of artificial and biomimetic camera applications.

Metagenomic insights into lignocellulose-degrading genes through Illumina-based de novo sequencing of the microbiome in Vietnamese native goats' rumen.

The scarcity of enzymes having an optimal activity in lignocellulose deconstruction is an obstacle for industrial-scale conversion of cellulosic biomass into biofuels. With the aim of mining novel lignocellulolytic enzymes, a ~9 Gb metagenome of bacteria in Vietnamese native goats' rumen was sequenced by Illumina platform. From the data, 821 ORFs encoding carbohydrate esterases (CEs) and polysaccharide lyases (PLs) serving for lignocellulose pre-treatment, 816 ORFs encoding 11 glycoside hydrolase families (GHs) of cellulases, and 2252 ORFs encoding 22 GHs of hemicellulases, were mined. The carbohydrate binding module (CBM) was also abundant with 763 ORFs, of which 480 ORFs are located with lignocellulolytic enzymes. The enzyme modularity analysis showed that CBMs are usually present in endoglucanase, endo 1,3-beta-D-glucosidase, and endoxylanase, whereas fibronectin 3-like module (FN3) mainly represents in GH3 and immunoglobulin-like domain (Ig) was located in GH9 only. Every domain located in each ORF was analyzed in detail to contribute enzymes' modularity which is valuable for modelling, to study the structure, and for recombinant production. With the aim of confirming the annotated results, a mined ORF encoding CBM63 was highly expressed in E. coli in soluble form. The purified recombinant CBM63 exhibited no cellulase activity, but enhanced a commercial cellulase activity in the destruction of a paper filter.

Metagenomic analysis of bacterial community structure and diversity of lignocellulolytic bacteria in Vietnamese native goat rumen.

OBJECTIVE: In a previous study, analysis of Illumina sequenced metagenomic DNA data of bacteria in Vietnamese goats' rumen showed a high diversity of putative lignocellulolytic genes. In this study, taxonomy speculation of microbial community and lignocellulolytic bacteria population in the rumen was conducted to elucidate a role of bacterial structure for effective degradation of plant materials. METHODS: The metagenomic data had been subjected into Basic Local Alignment Search Tool (BLASTX) algorithm and the National Center for Biotechnology Information non-redundant sequence database. Here the BLASTX hits were further processed by the Metagenome Analyzer program to statistically analyze the abundance of taxa. RESULTS: Microbial community in the rumen is defined by dominance of Bacteroidetes compared to Firmicutes. The ratio of Firmicutes versus Bacteroidetes was 0.36:1. An abundance of Synergistetes was uniquely identified in the goat microbiome may be formed by host genotype. With regard to bacterial lignocellulose degraders, the ratio of lignocellulolytic genes affiliated with Firmicutes compared to the genes linked to Bacteroidetes was 0.11:1, in which the genes encoding putative hemicellulases, carbohydrate esterases, polysaccharide lyases originated from Bacteroidetes were 14 to 20 times higher than from Firmicutes. Firmicutes seem to possess more cellulose hydrolysis capacity showing a Firmicutes/Bacteroidetes ratio of 0.35:1. Analysis of lignocellulolytic potential degraders shows that four species belonged to Bacteroidetes phylum, while two species belonged to Firmicutes phylum harbouring at least 12 different catalytic domains for all lignocellulose pretreatment, cellulose, as well as hemicellulose saccharification. CONCLUSION: Based on these findings, we speculate that increasing the members of Bacteroidetes to keep a low ratio of Firmicutes versus Bacteroidetes in goat rumen has resulted most likely in an increased lignocellulose digestion.

Independent Loss of Methylthioadenosine Phosphorylase (MTAP) in Primary Cutaneous T-Cell Lymphoma.

Methylthioadenosine phosphorylase (MTAP) and the tumor suppressor genes CDKN2A-CDKN2B are frequently deleted in malignancies. The specific role of MTAP in cutaneous T-cell lymphoma subgroups, mycosis fungoides (MF) and Sézary syndrome (SS), is unknown. In 213 skin samples from patients with MF/SS, MTAP copy number loss (34%) was more frequent than CDKN2A (12%) in all cutaneous T-cell lymphoma stages using quantitative reverse transcription PCR. Importantly, in early stage MF, MTAP loss occurred independently of CDKN2A loss in 37% of samples. In peripheral blood mononuclear cells from patients with SS, codeletion with CDKN2A occurred in 18% of samples but loss of MTAP alone was uncommon. In CD4(+) cells from SS, reduced MTAP mRNA expression correlated with MTAP copy number loss (P < 0.01) but reduced MTAP expression was also detected in the absence of copy number loss. Deep sequencing of MTAP/CDKN2A-CDKN2B loci in 77 peripheral blood mononuclear cell DNA samples from patients with SS did not show any nonsynonymous mutations, but read-depth analysis suggested focal deletions consistent with MTAP and CDKN2A copy number loss detected with quantitative reverse transcription PCR. In a cutaneous T-cell lymphoma cell line, promoter hypermethylation was shown to downregulate MTAP expression and may represent a mechanism of MTAP inactivation. In conclusion, our findings suggest that there may be selection in early stages of MF for MTAP deletion within the cutaneous tumor microenvironment.

Overexpression of miR-210, a downstream target of HIF1α, causes centrosome amplification in renal carcinoma cells.

MiR-210 is significantly up-regulated in clear cell renal cell carcinoma (CCC), but the mechanism and biological consequences of miR-210 up-regulation are poorly understood. Here, we show that miR-210 is highly expressed in renal carcinoma cell lines and that its expression is clearly correlated with accumulation of hypoxia-inducible factor 1α (HIF1α) under normoxia as well as hypoxia, suggesting that miR-210 up-regulation in renal carcinoma cells is most likely due to accumulation of HIF1α. To reveal the effects of miR-210 up-regulation, the miR-210 precursor was transfected into renal carcinoma cells. After transfection, the cells accumulated at the G2/M phase of the cell cycle and their viability was decreased, suggesting that miR-210 overexpression may trigger an event that hinders normal cell division. Immunocytochemistry demonstrated a multipolar spindle accompanied by centrosome amplification in cells overexpressing miR-210. It has been reported that centrosome amplification induces chromosome mis-segregation, finally leading to chromosome instability and aneuploidy. Indeed, the proportion of aneuploid cells (>4n) was increased in miR-210 overexpressed cells. By using the TargetScan and PicTar algorithms, E2F3 was identified as one of the possible targets of miR-210 and was suppressed at the protein level by miR-210. Moreover, the proportion of aneuploid cells was increased in E2F3 siRNA transfected cells. On the basis of these results, we propose that miR-210 up-regulation due to HIF1α accumulation may induce aneuploidy via E2F3 down-regulation at least in part, and may play a role in tumourigenesis and/or progression of CCC.

Polarized superfluidity in the attractive hubbard model with population imbalance.

We study a two-component Fermi system with attractive interactions and different populations of the two species in a cubic lattice. For an intermediate coupling, we find a uniformly polarized superfluid which is stable down to very low temperatures. The momentum distribution of this phase closely resembles that of the Sarma phase, characterized by two Fermi surfaces. This phase is shown to be stabilized by a potential energy gain, as in a BCS superfluid, in contrast with the unpolarized Bose-Einstein condensate which is stabilized by kinetic energy. We present general arguments suggesting that preformed pairs in the unpolarized superfluid favor the stabilization of a polarized superfluid phase.

Measuring the one-particle excitations of ultracold fermionic atoms by stimulated Raman spectroscopy.

We propose a Raman spectroscopy technique which is able to probe the one-particle Green function, the Fermi surface, and the quasiparticles of a gas of strongly interacting ultracold atoms. We give quantitative examples of experimentally accessible spectra. The efficiency of the method is validated by means of simulated images for the case of a usual Fermi liquid as well as for more exotic states: specific signatures of, e.g., a d-wave pseudogap are clearly visible.