Role of PAR1-Egr1 in the Initiation of Thoracic Aortic Aneurysm in Fbln4-Deficient Mice.

OBJECTIVE: Remodeling of the extracellular matrix plays a vital role in cardiovascular diseases. Using a mouse model of postnatal ascending aortic aneurysms (termed Fbln4SMKO), we have reported that abnormal mechanosensing led to aneurysm formation in Fbln4SMKO with an upregulation of the mechanosensitive transcription factor, Egr1 (Early growth response 1). However, the role of Egr1 and its upstream regulator(s) in the initiation of aneurysm development and their relationship to an aneurysmal microenvironment are unknown. Approach and Results: To investigate the contribution of Egr1 in the aneurysm development, we deleted Egr1 in Fbln4SMKO mice and generated double knockout mice (DKO, Fbln4SMKO; Egr1-/-). Aneurysms were prevented in DKO mice (42.8%) and Fbln4SMKO; Egr1+/- mice (26%). Ingenuity Pathway Analysis identified PAR1 (protease-activated receptor 1) as a potential Egr1 upstream gene. Protein and transcript levels of PAR1 were highly increased in Fbln4SMKO aortas at postnatal day 1 before aneurysm formed, together with active thrombin and MMP (matrix metalloproteinase)-9, both of which serve as a PAR1 activator. Concordantly, protein levels of PAR1, Egr1, and thrombin were significantly increased in human thoracic aortic aneurysms. In vitro cyclic stretch assays (1.0 Hz, 20% strain, 8 hours) using mouse primary vascular smooth muscle cells induced marked expression of PAR1 and secretion of prothrombin in response to mechanical stretch. Thrombin was sufficient to induce Egr1 expression in a PAR1-dependent manner. CONCLUSIONS: We propose that thrombin, MMP-9, and mechanical stimuli in the Fbln4SMKO aorta activate PAR1, leading to the upregulation of Egr1 and initiation of ascending aortic aneurysms.

Genetic Determinants and Genotype-Phenotype Correlations in Vietnamese Patients With Dilated Cardiomyopathy.

BACKGROUND: Dilated cardiomyopathy (DCM) is an important cause of heart failure and cardiac transplantation. This study determined the prevalence of DCM-associated genes and evaluated the genotype-phenotype correlation in Vietnamese patients.Methods and Results:This study analyzed 58 genes from 230 patients. The study cohort consisted of 64.3% men; age at diagnosis 47.9±13.7 years; familial (10.9%) and sporadic DCM (82.2%). The diagnostic yield was 23.5%, 44.0% in familial and 19.6% in sporadic DCM.TTNtruncating variants (TTNtv) were predominant (46.4%), followed byTPM1,DSP,LMNA,MYBPC3,MYH6,MYH7,DES,TNNT2,ACTC1,ACTN2,BAG3,DMD,FKTN,PLN,TBX5,RBM20,TCAP(2-6%). Familial DCM, genotype-positive andTTNtv-positive patients were younger than those with genotype-negative and sporadic DCM. Genotype-positive patients displayed a decreased systolic blood pressure and left ventricular wall thickness compared to genotype-negative patients. Genotype-positive patients, particularly those withTTNtv, had a family history of DCM, higher left atrial volume index and body mass index, and lower right ventricle-fractional area change than genotype-negative patients. Genotype-positive patients reached the combined outcomes more frequently and at a younger age than genotype-negative patients. Major cardiac events occurred more frequently in patients positive with genes other thanTTNtv. CONCLUSIONS: The study findings provided an overview of Vietnamese DCM patients' genetic profile and suggested that management of environmental factors may be beneficial for DCM patients.

Presence of Hypertrophic Cardiomyopathy Related Gene Mutations and Clinical Manifestations in Vietnamese Patients With Hypertrophic Cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is associated primarily with pathogenic mutations in sarcomeric genes. The aim of this study was to identify the prevalence and distribution of disease-causing mutations in HCM-associated genes and the genotype-phenotype relationship in Vietnamese patients with HCM.Methods and Results:Genetic testing was performed by next-generation sequencing in 104 unrelated probands for 23 HCM-related genes and in 57 family members for the mutation(s) detected. Clinical manifestations were recorded for genotype-phenotype correlation analysis. Mutation detection rate was 43.4%. Mutations inMYBPC3accounted for 38.6%, followed byTPM1(20.5%),MYH7(18.2%),TNNT2(9.1%),TNNI3(4.5%) andMYL2(2.3%). A mutation inGLAassociated with Fabry disease was found in 1 patient. A mutation inTPM1(c.842T>C, p.Met281Thr) was identified in 8 unrelated probands (18.2%) and 8 family members from 5 probands. Genotype-positive status related toMYH7,TPM1, andTNNT2mutations was associated with severe clinical manifestations.MYH7-positive patients displayed worse prognosis compared withMYBPC3-positive patients. Interestingly,TPM1c.842T>C mutation was associated with high penetrance and severe HCM phenotype. CONCLUSIONS: We report for the first time the prevalence of HCM-related gene variants in Vietnamese patients with HCM.MYH7,TPM1, andTNNT2mutations were associated with unfavorable prognosis.

Knowledge, experience and attitudes towards skin-to-skin contact following Caesarean sections among health professionals in Vietnam.

AIM: This study explored knowledge, experience and attitudes of health professionals towards early essential newborn care and skin-to-skin contact following Caesarean sections in a tertiary hospital in Central Vietnam. METHOD: We conducted a cross-sectional descriptive study using an anonymous questionnaire in March 2016. Health professionals from obstetrics, anaesthesiology and neonatology departments were surveyed. RESULTS: All of the 204 surveys were returned, accounting for 82% of total staff involved in the care for women and newborns with Caesarean sections. Correct knowledge of early essential newborn care was lowest among anaesthesiology staff. Health professionals reported that ≥90% of Caesarean section births they attended in the preceding week had skin-to-skin contact. Approximately 16% obstetricians, 71% midwives, 49% anaesthesiology and 76% neonatology staff considered the current frequency of skin-to-skin contact to be about right. The remainder considered the current rate too high. All professional groups identified the main difficulties of conducting skin-to-skin contact as the temperature in the operating theatre and the need for additional staff. Other concerns included increasing the risk of the baby of falling off, prolonging the operation and difficulty to monitor mothers. CONCLUSION: The study identifies issues where improvements can be made in the implementation of skin-to-skin contact following Caesarean sections.

K13 Propeller Mutations in Plasmodium falciparum Populations in Regions of Malaria Endemicity in Vietnam from 2009 to 2016.

The spread of artemisinin-resistant Plasmodium falciparum compromises the therapeutic efficacy of artemisinin combination therapies (ACTs) and is considered the greatest threat to current global initiatives to control and eliminate malaria. This is particularly relevant in Vietnam, where dihydroartemisinin-piperaquine (DP) is the recommended ACT for P. falciparum infection. The propeller domain gene of K13, a molecular marker of artemisinin resistance, was successfully sequenced in 1,060 P. falciparum isolates collected at 3 malaria hot spots in Vietnam between 2009 and 2016. Eight K13 propeller mutations (Thr474Ile, Tyr493His, Arg539Thr, Ile543Thr, Pro553Leu, Val568Gly, Pro574Leu, and Cys580Tyr), including several that have been validated to be artemisinin resistance markers, were found. The prevalences of K13 mutations were 29% (222/767), 6% (11/188), and 43% (45/105) in the Binh Phuoc, Ninh Thuan, and Gia Lai Provinces of Vietnam, respectively. Cys580Tyr became the dominant genotype in recent years, with 79.1% (34/43) of isolates in Binh Phuoc Province and 63% (17/27) of isolates in Gia Lai Province carrying this mutation. K13 mutations were associated with reduced ring-stage susceptibility to dihydroartemisinin (DHA) in vitro and prolonged parasite clearance in vivo An analysis of haplotypes flanking K13 suggested the presence of multiple strains with the Cys580Tyr mutation rather than a single strain expanding across the three sites.

Nam Dia long, a Vietnamese folk formula, induces apoptosis in MCF-7 cells through various mechanisms of action.

BACKGROUND: The holistic approach of traditional medicine renders the identification of its mechanisms of action difficult. Microarray technology provides an efficient way to analyze the complex genome-wide gene expression of cells treated with mixtures of medicinal ingredients. We performed transcriptional profiling of MCF-7 cells treated with Nam Dia Long (NDL), a Vietnamese traditional formula, to explore the mechanism of action underlying the apoptosis inducing effect of this formula reported in a previous study. METHODS: MCF-7 cells were treated with aqueous extracts of NDL at the IC50 concentration for 24, 36 and 48 h. Total RNAs at 24 h and 48 h were subsequently extracted, reverse transcribed and submitted to microarray expression profiling using the Human HT-12 v4.0 Expression Bead Chip (Illumina). Functional analyses were performed using the Database for Annotation, Visualization and Integrated Discovery and the Ingenuity Pathways Analysis. The expression level from selected genes at the three time points were assessed by quantitative real-time RT-PCR and Western blot. RESULTS: Fifty-four and 601 genes were differentially expressed at 24 and 48 h of NDL treatment, respectively. Genes with altered expression at 24 h were mostly involved in cell responses to xenobiotic stress whereas genes differentially expressed at 48 h were related to endoplasmic reticulum stress, DNA damage and cell cycle control. Apoptosis of NDL treated MCF-7 cells resulted from a combination of different mechanisms including the intrinsic and extrinsic pathways, cell cycle arrest- and oxidative stress-related cell death. CONCLUSION: NDL elicited a two-stage response in MCF-7 treated cells with apoptosis as the ultimate result. The various mechanisms inducing apoptosis reflected the complexity of the formula composition.

Women's communication self-efficacy and expectations of primary male partners' cooperation in sexually transmitted infection treatment in Ho Chi Minh City, Vietnam: a cross-sectional study.

BACKGROUND: Effective control of sexually transmitted infections (STIs) depends on affected patients notifying their sexual partners, and partners following through with screening and treatment. Our study assessed high-risk-STI women's confidence in STI-diagnosis-related communications with their primary male partners in Ho Chi Minh City, Vietnam, and determined associated characteristics of the women and their partners. METHODS: We employed convenience and snowball sampling in a clinic-based setting to recruit 126 women from August to October 2013. All data were obtained from women's self-report. RESULTS: The proportions of participants who were "slightly confident" or "very confident" that they could disclose their STI positivity to partners, ask partners to have an STI examination or treatment, and give partners bacterial-STI medications were 70.3%, 62.1%, and 69.0%, respectively. The proportions who perceived that their partners would be "very likely" to have an STI examination and to take STI medications were 16.2% and 38.8%, respectively. Significantly lower self-efficacy was observed in women who had a lower education level, who had ever traded sex, or whose primary partners were not husbands or fiancés. CONCLUSIONS: Our results suggest potential for piloting STI-partner-targeted interventions. To be effective, these programs should improve women's self-efficacy and primary partners' cooperation with screening and treatment.

Selective cytotoxicity of a Vietnamese traditional formula, Nam Dia long, against MCF-7 cells by synergistic effects.

BACKGROUND: Nam Dia Long (NDL) is a Vietnamese traditional formula used for the treatment of some chronic diseases, including cancers, but which lacks evidence-based support. We investigated the selective cytotoxicity of NDL on some tumor cell lines and possible interactions among its ingredients leading to the overall activity. METHODS: Crude aqueous extracts of NDL, its ingredients including Vigna radiata (L.) Wilczek, Vigna unguiculata (L.) Walp. subsp. unguiculata, Sauropus androgynous (L.) Merr and different ingredient combinations were used for the treatment of MCF-7, Hep G2, NCI-H460 cells and normal fibroblasts. The IC50 of NDL on tumor and normal cells were determined by sulforhodamine B (SRB) assay and used to calculate a selectivity index (SI). Apoptosis induction activity of NDL was determined by acridine orange - ethidium bromide (AO-EB) staining, genomic DNA and cell cycle analysis. The combination index (CI) reflecting the types of interactions among ingredients was calculated based on the median-effect principle. Real-time cell growth monitoring by the xCELLigence system was used to determine the kinetic profile of the treated MCF-7 cells. RESULTS: NDL exerted cytotoxicity on all tumor and normal cells, with the highest effect on MCF-7 cells. SI values for MCF-7, Hep G2 and NCI-H460 were 6.45, 1.61 and 1.29, respectively, indicating a high selective cytotoxicity of NDL toward MCF-7 cells. Profiles of cell death differed for MCF-7 cells and fibroblasts suggesting different mechanism of action of NDL toward these two cell types. The cytotoxicity of NDL against MCF-7 cells was due to apoptosis induction. NDL caused a cell cycle non-phase-specific effect on MCF-7 cells. CI indicated synergistic interactions among the ingredients leading to the overall activity of the complete formula. The real-time monitoring of MCF-7 cells growth after being treated with NDL and three-component combinations suggested that the presence of all ingredients was needed to reach the full cytotoxic activity. The growth kinetic profile of MCF-7 cells treated with different combinations also indicated a synergistic effect of all ingredients. CONCLUSION: NDL exhibited selective cytotoxicity toward MCF-7 cells. This effect probably resulted from synergistic interactions among the NDL ingredients. NDL should be explored for breast cancer treatment.

Indoor-Light-Activated Blue TiO2-Molecule-WO3 Visible Photocatalyst for Antibacterial Performance against Escherichia coli.

Currently used visible light catalysts either operate with high-power light sources or require prolonged periods of time for catalytic reactions. This presents a limitation regarding facile application in indoor environments and spaces frequented by the public. Furthermore, this gives rise to elevated power consumption. Here, we enhance photocatalytic performance with blue TiO2 and WO3 complexes covalently coupled through an organic molecule, 3-mercaptopropionic acid, under indoor light. Antibacterial experiments against 108 CFU/mL Escherichia coli (E. coli) suspensions were conducted under indoor light exposure conditions. They showed a sterilization effect of almost 90% within 70 min and nearly 100% after 110 min. The complex generates reactive oxygen species (ROS), such as •OH and O2•-, under natural air conditions. We also showed that h+ and •OH are important for sterilizing E. coli using common scavengers. This research highlights the potential of these complexes to generate ROS, effectively playing a crucial role in antibacterial effects under indoor light.

Neuropathogenesis-on-chips for neurodegenerative diseases.

Developing diagnostics and treatments for neurodegenerative diseases (NDs) is challenging due to multifactorial pathogenesis that progresses gradually. Advanced in vitro systems that recapitulate patient-like pathophysiology are emerging as alternatives to conventional animal-based models. In this review, we explore the interconnected pathogenic features of different types of ND, discuss the general strategy to modelling NDs using a microfluidic chip, and introduce the organoid-on-a-chip as the next advanced relevant model. Lastly, we overview how these models are being applied in academic and industrial drug development. The integration of microfluidic chips, stem cells, and biotechnological devices promises to provide valuable insights for biomedical research and developing diagnostic and therapeutic solutions for NDs.

Radiation-induced long-term dysphagia in survivors of head and neck cancer and association with dose-volume parameters.

BACKGROUND: Although dysphagia is a common side effect after radiotherapy (RT) of head and neck cancer (HNC), data on long-term dysphagia is scarce. We aimed to 1) compare radiation dose parameters in HNC survivors with and without dysphagia, 2) investigate factors associated with long-term dysphagia and its possible impact on health-related quality of life (HRQoL), and 3) investigate how our data agree with existing NTCP models. METHODS: This cross-sectional study conducted in 2018-2020, included HNC survivors treated in 2007-2013. Participants attended a one-day examination in hospital and filled in patient questionnaires. Dysphagia was measured with the EORTC QLQ-H&N35 swallowing scale. Toxicity was scored with CTCAE v.4. We contoured swallowing organs at risk (SWOAR) on RT plans, calculated dose-volume histograms (DVHs), performed logistic regression analyses and tested our data in established NTCP models. RESULTS: Of the 239 participants, 75 (31%) reported dysphagia. Compared to survivors without dysphagia, this group had reduced HRQoL and the DVHs for infrahyoid SWOAR were significantly shifted to the right. Long-term dysphagia was associated with age (OR 1.07, 95% CI 1.03-1.10), female sex (OR 2.75, 95% CI 1.45-5.21), and mean dose to middle pharyngeal constrictor muscle (MD-MPCM) (OR 1.06, 95% CI 1.03-1.09). NTCP models overall underestimated the risk of long-term dysphagia. CONCLUSIONS: Long-term dysphagia was associated with higher age, being female, and high MD-MPCM. Doses to distally located SWOAR seemed to be risk factors. Existing NTCP models do not sufficiently predict long-term dysphagia. Further efforts are needed to reduce the prevalence and consequences of this late effect.

Chronic fatigue in long-term survivors of head and neck cancer treated with radiotherapy.

BACKGROUND: There is lack of evidence on chronic fatigue (CF) following radiotherapy (RT) in survivors of head and neck cancer (HNC). We aimed to compare CF in HNC survivors > 5 years post-RT with a reference population and investigate factors associated with CF and the possible impact of CF on health-related quality of life (HRQoL). MATERIAL AND METHODS: In this cross-sectional study we included HNC survivors treated in 2007-2013. Participants filled in patient-reported outcome measures and attended a one-day examination. CF was measured with the Fatigue Questionnaire and compared with a matched reference population using t-tests and Cohen's effect size. Associations between CF, clinical and RT-related factors were investigated using logistic regression. HRQoL was measured with the EORTC Quality of Life core questionnaire. RESULTS: The median age of the 227 HNC survivors was 65 years and median time to follow-up was 8.5 years post-RT. CF was twice more prevalent in HNC survivors compared to a reference population. In multivariable analyses, female sex (OR 3.39, 95 % CI 1.82-6.31), comorbidity (OR 2.17, 95 % CI 1.20-3.94) and treatment with intensity-modulated RT (OR 2.13, 95 % CI 1.16-3.91) were associated with CF, while RT dose parameters were not. Survivors with CF compared to those without, had significantly worse HRQoL. CONCLUSIONS: CF in HNC survivors is particularly important for female patients, while specific factors associated with RT appear not to play a role. The high CF prevalence in long-term HNC survivors associated with impaired HRQoL is important information beneficial for clinicians and patients to improve patient follow-up.

Asymptomatic congenital ductus arteriosus aneurysm in a newborn: Case by approach.

A ductus arteriosus aneurysm is a rare congenital lesion with a localized saccular or tubular dilation of the ductus arteriosus. This lesion usually appears in all ages. Some case reports suggest the most common age of diagnosis is less than 2 months. We reported a case of an asymptomatic ductus arteriosus aneurysm in neonates. Echocardiography at 2 days of age revealed a tubular dilation of the ductus arteriosus connected to the pulmonary artery. Computed tomography angiogram showed a ductus arteriosus aneurysm with thrombus at the pulmonary end. It resolved spontaneously in the six months of life without serious complications.

Increasing charge transfer of SERS by the combination of amorphous Al2O3-Al thin film and ZnO nanorods decorated with Ag nanoparticles for trace detection of metronidazole.

In this work, we study the charge transfer improvement by the combination of two semiconductors of SERS. The energy levels of the semiconductor, when combined, become intermediate energy levels that support the charge transfer from the HOMO to the LUMO level, amplifying the Raman signal of the organic molecules. The SERS substrates of Ag/a-Al2O3-Al/ZnO nanorods with high sensitivity are prepared for detecting dye rhodamine 6G (R6G) and metronidazole (MNZ) standard. The highly ordered vertically grown ZnO nanorods (NRs) are first developed on a glass substrate by a wet chemical bath deposition method. Then, ZnO NRs are covered with an amorphous oxidized aluminum thin film by a vacuum thermal evaporation method to produce a platform with a large surface area and high charge transfer performance. Finally, silver nanoparticles (NPs) are decorated onto this platform to form an active SERS substrate. The structure, surface morphology, optical properties, and elements in the sample are investigated by Raman spectroscopy, X-ray diffractometry, field-emission scanning electron microscopy (FE-SEM), ultraviolet-visible spectroscopy (UV-vis), reflectance spectroscopy, and energy dispersion X-ray spectroscopy (EDS). Rhodamine 6G is used as a reagent to evaluate the SERS substrates with an analytical enhancement factor (EF) of ∼1.85 × 1010 at the limit of detection (LOD) of 10-11 M. These SERS substrates are used to detect metronidazole standard at a LOD of 0.01 ppm and an EF of 2.2 × 106. The SERS substrate exhibits high sensitivity and stability for promising wide application in chemical, biomedical, and pharmaceutical detection.

Protective Role of Endothelial Fibulin-4 in Valvulo-Arterial Integrity.

Background Homeostasis of the vessel wall is cooperatively maintained by endothelial cells (ECs), smooth muscle cells, and adventitial fibroblasts. The genetic deletion of fibulin-4 (Fbln4) in smooth muscle cells (SMKO) leads to the formation of thoracic aortic aneurysms with the disruption of elastic fibers. Although Fbln4 is expressed in the entire vessel wall, its function in ECs and relevance to the maintenance of valvulo-arterial integrity are not fully understood. Methods and Results Gene silencing of FBLN4 was conducted on human aortic ECs to evaluate morphological changes and gene expression profile. Fbln4 double knockout (DKO) mice in ECs and smooth muscle cells were generated and subjected to histological analysis, echocardiography, Western blotting, RNA sequencing, and immunostaining. An evaluation of the thoracic aortic aneurysm phenotype and screening of altered signaling pathways were performed. Knockdown of FBLN4 in human aortic ECs induced mesenchymal cell-like changes with the upregulation of mesenchymal genes, including TAGLN and MYL9. DKO mice showed the exacerbation of thoracic aortic aneurysms when compared with those of SMKO and upregulated Thbs1, a mechanical stress-responsive molecule, throughout the aorta. DKO mice also showed progressive aortic valve thickening with collagen deposition from postnatal day 14, as well as turbulent flow in the ascending aorta. Furthermore, RNA sequencing and immunostaining of the aortic valve revealed the upregulation of genes involved in endothelial-to-mesenchymal transition, inflammatory response, and tissue fibrosis in DKO valves and the presence of activated valve interstitial cells. Conclusions The current study uncovers the pivotal role of endothelial fibulin-4 in the maintenance of valvulo-arterial integrity, which influences thoracic aortic aneurysm progression.

Sweet Wormwood and Tortoise Shell Decoction (Thanh Hao Miet Giap Thang) Induces DNA Damage, S-Phase Arrest, and Apoptosis in MCF-7 Cells via ATR-CHK1 Signaling Pathway.

Introduction: Sweet wormwood and tortoise shell decoction, Thanh Hao Miet Giap Thang (THMGT) in Vietnamese, a traditional formula composed of five ingredients, is used in complementary care in Vietnam for patients who underwent conventional cancer treatment. To expand the clinical use and explore novel functions of THMGT, this study was conducted to investigate the effect of THMGT in terms of antiproliferative activity and selective cytotoxicity toward human breast cancer cells MCF-7. Methods: Cytotoxicity of THMGT against human breast cancer cells MCF-7 and primary fibroblasts from a heathy donor were studied using sulforhodamine B (SRB) assay. Flow cytometry analysis, immunofluorescence, and western blotting were also performed to elucidate underlying mechanisms of THMGT action. Results: The SRB assay on treated MCF-7 cells and primary fibroblasts from a heathy donor indicated selective cytotoxicity of THMGT with a selective index of 3.92. Annexin V/PI staining and flow cytometric analysis on stained MCF-7 cells showed that the THMGT-treated cells were arrested at the S phase and subsequently underwent apoptosis. Western blot analysis showed an upregulation of γ-H2AX, increased protein levels of phosphorylated CHK1, TP53, and phosphorylated TP53 in a time-dependent manner, and a downregulated expression of ATR and MDM2. Conclusion: These results suggested DNA damaging effect and ATR-CHK1-mediated cell cycle arrest of THMGT on MCF-7 cells resulting in apoptosis induction.

Investigating risk factors behind piglet facial and sow teat lesions through a literature review and a survey on teeth reduction.

Introduction: Piglet facial and sow teat lesions are the main reported reasons why pig producers routinely practice teeth resection. This is a painful procedure performed on piglets, where their needle teeth are clipped or ground to resect the pointed tip. The practice raises welfare concerns. In contrast to other procedures, such as tail docking, we know little about the risk factors for these two types of lesions. Methods: We employed two methods to answer these questions: (1) reviewing the literature to identify potential risk factors, and (2) surveying pig production stakeholders worldwide to identify the occurrence of these lesions and the strategies used in practice that enable pig producers to manage or prevent these lesions while avoiding teeth resection. For the literature review, we used Google Scholar to include peer-reviewed publications and gray literature. We distributed the survey using convenience sampling and documented information on the current situation regarding teeth resection, including the methods, frequencies, and reasons for resecting piglets' teeth, the occurrence of piglet facial and sow teat lesions, and measures used to prevent and control these lesions. Results: The literature review identified six major risk factors for both lesions, including the presence or absence of teeth resection, housing system, litter size, piglet management, environmental enrichment, milk production and other piglet management practices. However, most studies focused on the effects of the first two factors with very few studies investigating the other risk factors. There were 75 responses to the survey from 17 countries. The survey showed that half of the respondents practiced teeth resection with many recognizing that facial and teat lesions are the main reasons behind this practice. However, many producers used other interventions rather than teeth resection to prevent these lesions. These interventions focused on improving milk production of the sow, managing large litters, and providing environmental enrichment. Discussion: More research is needed to validate these interventions and more science-based advice is needed to bridge the gap between research and practice to help more producers further understand the cause of piglet facial and sow teat lesions to transition toward the cessation of routine teeth resection.

Rukamtenol, a new spiro compound isolated from Flacourtia rukam Zoll. & Moritzi growing in Vietnam.

Chemical investigation of chloroform extract of Flacourtia rukam Zoll. & Moritzi stems led to the isolation of one new compound namely rukamtenol together with four known compounds, viz., chaulmooric acid, flacourtin, 3,4,5-trimethoxyphenyl ß-D-glucopyranoside, and daucosterol. Their structures and relative stereochemistry have been determined by 1D and 2D NMR analysis, high resolution mass spectroscopy, and compared with those in literatures. Rukamtenol represented the first 2-oxaspiro[4.4]non-8-en-3-one in nature. The relative configuration of rukamtinol was defined using DFT-NMR chemical shift calculations and subsequent DP4 probability method. Rukamtenol, flacourtin, and 3,4,5-trimethoxyphenyl ß-D-glucopyranoside were tested for cytotoxic activity toward three MDA-MB-231, HepG2, and RD cancer cell lines. However, they failed to reveal any activity (IC50 > 100 µM) on these cell lines.

Microbial Diversity Analysis Using 16S rRNA Gene Amplicon Sequencing of Rhizosphere Soils from Double-Cropping Rice and Rice-Shrimp Farming Systems in Soc Trang, Vietnam.

Different rice farming systems affect the soil microbial communities. Here, we report the results of 16S rRNA gene amplicon sequencing of soils collected from intensive rice cultivation and rice-shrimp farming systems in Soc Trang, Vietnam. The dominant phyla in these systems were Firmicutes, Actinobacteriota, Chloroflexi, Myxococcota, and Acidobacteriota.

Glycosylation steps during spiramycin biosynthesis in Streptomyces ambofaciens: involvement of three glycosyltransferases and their interplay with two auxiliary proteins.

Streptomyces ambofaciens synthesizes spiramycin, a 16-membered macrolide antibiotic used in human medicine. The spiramycin molecule consists of a polyketide lactone ring (platenolide) synthesized by a type I polyketide synthase, to which three deoxyhexoses (mycaminose, forosamine, and mycarose) are attached successively in this order. These sugars are essential to the antibacterial activity of spiramycin. We previously identified four genes in the spiramycin biosynthetic gene cluster predicted to encode glycosyltransferases. We individually deleted each of these four genes and showed that three of them were required for spiramycin biosynthesis. The role of each of the three glycosyltransferases in spiramycin biosynthesis was determined by identifying the biosynthetic intermediates accumulated by the corresponding mutant strains. This led to the identification of the glycosyltransferase responsible for the attachment of each of the three sugars. Moreover, two genes encoding putative glycosyltransferase auxiliary proteins were also identified in the spiramycin biosynthetic gene cluster. When these two genes were deleted, one of them was found to be dispensable for spiramycin biosynthesis. However, analysis of the biosynthetic intermediates accumulated by mutant strains devoid of each of the auxiliary proteins (or of both of them), together with complementation experiments, revealed the interplay of glycosyltransferases with the auxiliary proteins. One of the auxiliary proteins interacted efficiently with the two glycosyltransferases transferring mycaminose and forosamine while the other auxiliary protein interacted only with the mycaminosyltransferase.