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1.
Development ; 149(1)2022 01 01.
Article in English | MEDLINE | ID: mdl-35020896

ABSTRACT

In early placental development, progenitor cytotrophoblasts (CTB) differentiate along one of two cellular trajectories: the villous or extravillous pathways. CTB committed to the villous pathway fuse with neighboring CTB to form the outer multinucleated syncytiotrophoblast (SCT), whereas CTB committed to the extravillous pathway differentiate into invasive extravillous trophoblasts (EVT). Unfortunately, little is known about the processes controlling human CTB progenitor maintenance and differentiation. To address this, we established a single cell RNA sequencing (scRNA-seq) dataset from first trimester placentas to identify cell states important in trophoblast progenitor establishment, renewal and differentiation. Multiple distinct trophoblast states were identified, representing progenitor CTB, column CTB, SCT precursors and EVT. Lineage trajectory analysis identified a progenitor origin that was reproduced in human trophoblast stem cell organoids. Heightened expression of basal cell adhesion molecule (BCAM) defined this primitive state, where BCAM enrichment or gene silencing resulted in enhanced or diminished organoid growth, respectively. Together, this work describes at high-resolution trophoblast heterogeneity within the first trimester, resolves gene networks within human CTB progenitors and identifies BCAM as a primitive progenitor marker and possible regulator.


Subject(s)
Cell Adhesion Molecules/metabolism , Cell Lineage , Lutheran Blood-Group System/metabolism , Trophoblasts/metabolism , Adult , Cell Adhesion Molecules/genetics , Cell Differentiation , Cells, Cultured , Female , Gene Expression Regulation, Developmental , Gene Regulatory Networks , Human Embryonic Stem Cells/cytology , Human Embryonic Stem Cells/metabolism , Humans , Lutheran Blood-Group System/genetics , Organoids/cytology , Organoids/metabolism , Trophoblasts/cytology
2.
PLoS Genet ; 18(1): e1009519, 2022 01.
Article in English | MEDLINE | ID: mdl-35077443

ABSTRACT

The blood brain barrier (BBB) forms a stringent barrier that protects the brain from components in the circulation that could interfere with neuronal function. At the same time, the BBB enables selective transport of critical nutrients and other chemicals to the brain. Beyond these functions, another recently recognized function is even less characterized, specifically the role of the BBB in modulating behavior by affecting neuronal function in a sex-dependent manner. Notably, signaling in the adult Drosophila BBB is required for normal male courtship behavior. Courtship regulation also relies on male-specific molecules in the BBB. Our previous studies have demonstrated that adult feminization of these cells in males significantly lowered courtship. Here, we conducted microarray analysis of BBB cells isolated from males and females. Findings revealed that these cells contain male- and female-enriched transcripts, respectively. Among these transcripts, nuclear receptor Hr46/Hr3 was identified as a male-enriched BBB transcript. Hr46/Hr3 is best known for its essential roles in the ecdysone response during development and metamorphosis. In this study, we demonstrate that Hr46/Hr3 is specifically required in the BBB cells for courtship behavior in mature males. The protein is localized in the nuclei of sub-perineurial glial cells (SPG), indicating that it might act as a transcriptional regulator. These data provide a catalogue of sexually dimorphic BBB transcripts and demonstrate a physiological adult role for the nuclear receptor Hr46/Hr3 in the regulation of male courtship, a novel function that is independent of its developmental role.


Subject(s)
Blood-Brain Barrier/metabolism , Courtship , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Drosophila melanogaster/physiology , Receptors, Cytoplasmic and Nuclear/genetics , Receptors, Cytoplasmic and Nuclear/metabolism , Animals , Drosophila melanogaster/genetics , Ecdysone/metabolism , Female , Gene Expression Profiling , Gene Expression Regulation , Male , Oligonucleotide Array Sequence Analysis , Sex Characteristics , Sexual Behavior, Animal/physiology
3.
J Hepatol ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38986744

ABSTRACT

BACKGROUND & AIMS: An optimal HCV vaccine requires the induction of antibodies that neutralise the infectivity of many heterogenous viral isolates. In this study, we have focused on determining the optimal recombinant envelope glycoprotein component to elicit cross-neutralising antibodies against global HCV genotypes. We compared the immunoreactivity and antigenicity of the HCV genotype 1a strain H77C-derived envelope glycoprotein heterodimer gpE1/gpE2 with that of recombinant gpE2 alone. METHODS: Characterisation of the envelope glycoproteins was accomplished by determining their ability to bind to a panel of broadly cross-neutralising monoclonal antibodies. Immunogenicity was determined by testing the ability of vaccine antisera to neutralise the infectivity in vitro of a panel of pseudotyped HCV particles in which gpE1/gpE2 derived from representative isolates of the major global HCV genotypes were displayed. RESULTS: gpE1/gpE2 binds to more diverse broadly cross-neutralising antibodies than gpE2 alone and elicits a broader profile of cross-neutralising antibodies in animals, especially against more heterologous, non-1a genotypes. While not all heterologous HCV strains can be potently inhibited in vitro by gpE1/gpE2 antisera derived from a single HCV strain, the breadth of heterologous cross-neutralisation is shown to be substantial. CONCLUSIONS: Our work supports the inclusion of gpE1/gpE2 in an HCV vaccine in order to maximise the cross-neutralisation of heterogenous HCV isolates. Our data also offers future directions in formulating a cocktail of gpE1/gpE2 antigens from a small selection of HCV genotypes to further enhance cross-neutralisation of global HCV strains and hopefully advance the development of a globally effective HCV vaccine. IMPACT AND IMPLICATIONS: An HCV vaccine is urgently required to prevent the high global incidence of HCV infection and disease. Since HCV is a highly heterogeneous virus, it is desirable for a vaccine to elicit antibodies that neutralise the infectivity of most global strains. To this end, we have compared the immunoreactivity and antigenicity of recombinant H77C E1E2 heterodimer with that of H77C E2 alone and show that the former exhibits more cross-neutralising epitopes and demonstrates a broader cross-neutralisation profile in vitro. In addition, our data suggests a way to further broaden cross-neutralisation using a combination of E1E2 antigens derived from a few different HCV clades. Our work is relevant for the development of an effective global HCV vaccine.

4.
Reprod Biomed Online ; 49(3): 104112, 2024 09.
Article in English | MEDLINE | ID: mdl-39013260

ABSTRACT

RESEARCH QUESTION: What is the diagnostic accuracy of hysterosalpingo-foam sonography (HyFoSy), using two-dimensional ultrasound in tubal patency assessment in infertile women compared with laparoscopy with dye chromotubation? DESIGN: This prospective study was conducted at My Duc Hospital, Vietnam. Infertile women aged 18 years or older, who were scheduled for laparoscopy, were included. Visual Analogue Scale (VAS) score for perception of pain during HyFoSy was used. Laparoscopy was carried out on the same day. Clinicians undertaking laparoscopy were blinded to HyFoSy results. Sensitivity, specificity, negative and positive predictive value, and 95% confidence intervals were calculated. A sample size of 455 women (n = 910 fallopian tubes) was needed to demonstrate a fluctuation hypothesis, not exceeding 6%, for sensitivity and specificity (power 0.80, two-sided alpha 5%, loss to follow-up 5%). RESULTS: Between 2019 and 2022, 455 participants were recruited. Hysterosalpingo-foam sonography was unsuccessfully carried out in six participants. Two withdrew their consent. Data analysis was conducted on the remaining 447 participants (n = 868 fallopian tubes). The sensitivity and specificity of hysterosalpingo-foam sonography compared with laparoscopy were 0.75 (95% CI 0.71 to 0.79) and 0.70 (95% CI 0.65 to 0.74), respectively. Hysterosalpingo-foam sonography gave a positive predictive value of 0.76 (95% CI 0.73 to 0.80) and negative predictive value of 0.68 (95% CI 0.64 to 0.73). A total of 42.8% of women reported a VAS score of no pain. No adverse event was reported. CONCLUSION: Compared with laparoscopy with dye chromotubation, two-dimensional HyFoSy is a well-tolerated, reliable technique for assessing tubal patency.


Subject(s)
Fallopian Tube Patency Tests , Fallopian Tubes , Infertility, Female , Laparoscopy , Ultrasonography , Humans , Female , Infertility, Female/diagnostic imaging , Adult , Fallopian Tubes/diagnostic imaging , Ultrasonography/methods , Fallopian Tube Patency Tests/methods , Prospective Studies , Sensitivity and Specificity , Young Adult , Hysterosalpingography/methods
5.
BMC Neurol ; 24(1): 51, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38297247

ABSTRACT

BACKGROUND: This retrospective study examined the humanistic burden of fatigue in patients with relapsing-remitting multiple sclerosis (RRMS), compared with adults without MS, using data from the 2017 and 2019 US National Health and Wellness Survey. METHODS: The 5-item Modified Fatigue Impact Scale (MFIS-5) was used to assess level of fatigue (MFIS-5 score <15: low fatigue [LF]; MFIS-5 score ≥15: high fatigue [HF]) in patients with RRMS. Health-related quality of life (HRQoL) measures (Short Form 36-Item Health Survey version 2, Euroqol-5 Dimensions-5 Levels [EQ-5D-5L], Patient Health Questionnaire-9 [PHQ-9], Generalized Anxiety Disorder-7 [GAD-7], Perceived Deficits Questionnaire-5) and treatment-related characteristics were assessed. RESULTS: In total, 498 respondents were identified as RRMS (n=375 RRMS+LF, n=123 RRMS+HF) and compared with 1,494 matched non-MS controls. RRMS+LF and RRMS+HF had significantly lower Short Form 6 Dimensions health utility, Mental and Physical Component Summary, and EQ-5D-5L scores and higher PHQ-9 and GAD-7 scores, compared with matched non-MS controls (all p<0.001); scores were worse for RRMS+HF than RRMS+LF across all measures (all p<0.001). A higher proportion of RRMS+HF reported moderate-to-severe depression and moderate-to-severe anxiety, compared with RRMS+LF and matched non-MS controls (both p<0.001). Fatigue was a significant predictor of poor HRQoL across all measures (all p<0.001). CONCLUSIONS: Patients with RRMS experienced lower HRQoL with higher levels of fatigue, highlighting an unmet need. Results may help to inform physician-patient communication and shared decision-making to address fatigue and its associated impact on patients' HRQoL.


Subject(s)
Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Adult , Humans , Multiple Sclerosis/complications , Multiple Sclerosis/epidemiology , Quality of Life , Retrospective Studies , Multiple Sclerosis, Relapsing-Remitting/complications , Multiple Sclerosis, Relapsing-Remitting/epidemiology , Health Surveys , Fatigue/epidemiology , Fatigue/etiology
6.
BMC Neurol ; 24(1): 378, 2024 Oct 08.
Article in English | MEDLINE | ID: mdl-39379875

ABSTRACT

BACKGROUND: Brain volume loss (BVL) has been identified as a predictor of disability progression in relapsing multiple sclerosis (RMS). As many available disease-modifying treatments (DMTs) have shown an effect on slowing BVL, this is becoming an emerging clinical endpoint in RMS clinical trials. METHODS: In this study, a systematic literature review was conducted to identify BVL results from randomized controlled trials of DMTs in RMS. Indirect treatment comparisons (ITCs) were conducted to estimate the relative efficacy of DMTs on BVL using two approaches: a model-based meta-analysis (MBMA) with adjustment for measurement timepoint and DMT dosage, and a network meta-analysis (NMA). RESULTS: In the MBMA, DMTs associated with significantly reduced BVL versus placebo at two years included fingolimod (mean difference [MD] = 0.25; 95% confidence interval [CI] = 0.15 - 0.36), ozanimod (MD = 0.26; 95% CI = 0.12 - 0.41), teriflunomide (MD = 0.38; 95% CI = 0.20 - 0.55), alemtuzumab (MD = 0.38; 95% CI = 0.10 - 0.67) and ponesimod (MD = 0.71; 95% CI = 0.48 - 0.95), whereas interferons and natalizumab performed the most poorly. The results of NMA analysis were generally comparable with those of the MBMA. CONCLUSIONS: Limitations of these analyses included the potential for confounding due to pseudoatrophy, and a lack of long-term clinical data for BVL. Our findings suggest that important differences in BVL may exist between DMTs. Continued investigation of BVL in studies of RMS is important to complement traditional disability endpoints, and to foster a better understanding of the mechanisms by which DMTs can slow BVL.


Subject(s)
Brain , Multiple Sclerosis, Relapsing-Remitting , Humans , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Multiple Sclerosis, Relapsing-Remitting/diagnostic imaging , Multiple Sclerosis, Relapsing-Remitting/pathology , Brain/diagnostic imaging , Brain/pathology , Brain/drug effects , Randomized Controlled Trials as Topic/methods , Immunologic Factors/therapeutic use , Immunosuppressive Agents/therapeutic use , Fingolimod Hydrochloride/therapeutic use
7.
BMC Infect Dis ; 24(1): 800, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39118006

ABSTRACT

Liver injury with marked elevation of aspartate aminotransferase enzyme (AST) is commonly observed in dengue infection. To understand the pathogenesis of this liver damage, we compared the plasma levels of hepatic specific, centrilobular predominant enzymes (glutamate dehydrogenase, GLDH; glutathione S transferase-α, αGST), periportal enriched 4-hydroxyphenylpyruvate dioxygenase (HPPD), periportal predominant arginase-1 (ARG-1), and other non-specific biomarkers (paraoxonase-1, PON-1) in patients with different outcomes of dengue infection. This hospital-based study enrolled 87 adult dengue patients, stratified into three groups based on plasma AST levels (< 80, 80-400, > 400 U/L) in a 1:1:1 ratio (n = 40, n = 40, n = 40, respectively. The new liver enzymes in the blood samples from the 4th to 6th days of their illness were measured by commercial enzyme-linked immunosorbent assay (ELISA) or colorimetric kits. Based on the diagnosis at discharge days, our patients were classified as 40 (46%) dengue without warning signs (D), 35 (40.2%) dengue with warning signs (DWS), and 11 (12.6%) severe dengue (SD) with either shock (two patients) or AST level over 1000 U/L (nine patients), using the 2009 WHO classification. The group of high AST (> 400 U/L) also had higher ALT, GLDH, ARG-1, and HPPD than the other groups, while the high (> 400 U/L) and moderate (80-400 U/L) AST groups had higher ALT, αGST, ARG-1, and HPPD than the low AST group (< 80 U/L). There was a good correlation between AST, alanine aminotransferase enzyme (ALT), and the new liver biomarkers such as GLDH, αGST, ARG-1, and HPPD. Our findings suggest that dengue-induced liver damage initiates predominantly in the centrilobular area toward the portal area during the dengue progression. Moreover, these new biomarkers should be investigated further to explain the pathogenesis of dengue and to validate their prognostic utility.


Subject(s)
Aspartate Aminotransferases , Biomarkers , Dengue , Liver , Humans , Male , Biomarkers/blood , Female , Adult , Dengue/blood , Dengue/diagnosis , Dengue/complications , Case-Control Studies , Middle Aged , Aspartate Aminotransferases/blood , Vietnam , Liver/pathology , Young Adult , Liver Diseases/blood , Glutathione Transferase/blood , Aged , Southeast Asian People
8.
Public Health Nutr ; : 1-37, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38804077

ABSTRACT

OBJECTIVE: SEANUTS II Vietnam aims to obtain an in-depth understanding of the nutritional status and nutrient intake of children between 0.5-11.9 years old. DESIGN: Cross-sectional survey. SETTING: A multistage cluster systematic random sampling method was implemented in different regions in Vietnam: North Mountainous, Central Highlands, Red River Delta, North Central and Coastal Area, Southeast and Mekong River Delta. PARTICIPANTS: 4001 children between 6 months and 11.9 years of age. RESULTS: Prevalence of stunting and underweight was higher in rural than in urban children, whereas overweight and obese rates were higher in urban areas. 12.0% of the children had anemia and especially children 0.5-1-year-old were affected (38.6%). Low serum retinol was found in 6.2% of children ≥ 4 years old. Prevalence of vitamin D insufficiency was 31.1% while 60.8% had low serum zinc. For nutrient intake, overall, 80.1% of the children did not meet the estimated energy requirements. For calcium intake, ∼60% of the younger children did not meet the RNI while it was 92.6% in children >7 years old. For vitamin D intake, 95.0% of the children did not meet RNI. CONCLUSIONS: SEANUTS II Vietnam indicated that overnutrition was more prevalent than undernutrition in urban areas, while undernutrition was found more in rural areas. The high prevalence of low serum zinc, vitamin D insufficiency and the inadequate intakes of calcium and vitamin D are of concern. Nutrition strategies for Vietnamese children should consider three sides of malnutrition and focus on approaches for the prevention malnutrition.

9.
PLoS Genet ; 17(6): e1009594, 2021 06.
Article in English | MEDLINE | ID: mdl-34097698

ABSTRACT

The number of grains per panicle is an important yield-related trait in cereals which depends in part on panicle branching complexity. One component of this complexity is the number of secondary branches per panicle. Previously, a GWAS site associated with secondary branch and spikelet numbers per panicle in rice was identified. Here we combined gene capture, bi-parental genetic population analysis, expression profiling and transgenic approaches in order to investigate the functional significance of a cluster of 6 ANK and ANK-TPR genes within the QTL. Four of the ANK and ANK-TPR genes present a differential expression associated with panicle secondary branch number in contrasted accessions. These differential expression patterns correlate in the different alleles of these genes with specific deletions of potential cis-regulatory sequences in their promoters. Two of these genes were confirmed through functional analysis as playing a role in the control of panicle architecture. Our findings indicate that secondary branching diversity in the rice panicle is governed in part by differentially expressed genes within this cluster encoding ANK and ANK-TPR domain proteins that may act as positive or negative regulators of panicle meristem's identity transition from indeterminate to determinate state.


Subject(s)
Ankyrins/genetics , Oryza/genetics , Repetitive Sequences, Nucleic Acid , Gene Expression Regulation, Plant , Genes, Plant , Quantitative Trait Loci
10.
Curr Issues Mol Biol ; 45(3): 2213-2229, 2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36975513

ABSTRACT

Salmonella enterica is one of the most dangerous foodborne pathogens listed by the World Health Organization. In this study, whole-duck samples were collected at wet markets in five districts in Hanoi, Vietnam, in October 2019 to assess their Salmonella infection rates and evaluate the susceptibility of the isolated strains to antibiotics currently used in the prophylaxis and treatment of Salmonella infection. Based on the antibiotic resistance profiles, eight multidrug resistance strains were whole-genome-sequenced, and their antibiotic resistance genes, genotypes, multi-locus sequence-based typing (MLST), virulence factors, and plasmids were analyzed. The results of the antibiotic susceptibility test indicate that phenotypic resistance to tetracycline and cefazolin was the most common (82.4%, 28/34 samples). However, all isolates were susceptible to cefoxitin and meropenem. Among the eight sequenced strains, we identified 43 genes associated with resistance to multiple classes of antibiotics such as aminoglycoside, beta-lactam, chloramphenicol, lincosamide, quinolone, and tetracycline. Notably, all strains carried the blaCTX-M-55 gene, which confers resistance to third-generation antibiotics including cefotaxime, cefoperazone, ceftizoxime, and ceftazidime, as well as resistance genes of other broad-spectrum antibiotics used in clinical treatment such as gentamicin, tetracycline, chloramphenicol, and ampicillin. Forty-three different antibiotic resistance genes were predicted to be present in the isolated Salmonella strains' genomes. In addition, three plasmids were predicted in two strains, 43_S11 and 60_S17. The sequenced genomes also indicated that all strains carried SPI-1, SPI-2, and SPI-3. These SPIs are composed of antimicrobial resistance gene clusters and thus represent a potential threat to public health management. Taken together, this study highlights the extent of multidrug-resistant Salmonella contamination in duck meat in Vietnam.

11.
Development ; 147(2)2020 01 23.
Article in English | MEDLINE | ID: mdl-31871275

ABSTRACT

Early placental development and the establishment of the invasive trophoblast lineage take place within a low oxygen environment. However, conflicting and inconsistent findings have obscured the role of oxygen in regulating invasive trophoblast differentiation. In this study, the effect of hypoxic, normoxic and atmospheric oxygen on invasive extravillous pathway progression was examined using a human placental explant model. Here, we show that exposure to low oxygen enhances extravillous column outgrowth and promotes the expression of genes that align with extravillous trophoblast (EVT) lineage commitment. By contrast, supra-physiological atmospheric levels of oxygen promote trophoblast proliferation while simultaneously stalling EVT progression. Low oxygen-induced EVT differentiation coincided with elevated transcriptomic levels of lysyl oxidase (LOX) in trophoblast anchoring columns, in which functional experiments established a role for LOX activity in promoting EVT column outgrowth. The findings of this work support a role for low oxygen in potentiating the differentiation of trophoblasts along the extravillous pathway. In addition, these findings generate insight into new molecular processes controlled by oxygen during early placental development.


Subject(s)
Cell Differentiation/drug effects , Cell Lineage/drug effects , Oxygen/pharmacology , Protein-Lysine 6-Oxidase/metabolism , Trophoblasts/cytology , Adult , Cell Hypoxia/drug effects , Female , Gene Expression Regulation, Developmental/drug effects , Humans , Models, Biological , Transcriptome/genetics , Young Adult
12.
Drug Metab Dispos ; 51(7): 862-872, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37059472

ABSTRACT

Navoximod (GDC-0919) is a small molecule inhibitor of indoleamine 2,3-dioxygenase 1 (IDO1) developed to reduce T cell immunosuppression associated with cancer. This study describes the absorption, metabolism, and excretion (AME) of navoximod in rats and dogs after a single oral dose of [14C]-navoximod. An unexpected thiocyanate metabolite M1 and a chiral inversion metabolite M51 were captured as the major circulating metabolites in rats, accounting for 30% and 18% of 0-24 hours exposure, respectively. These two metabolites combined had much lower systemic exposure in dogs and humans (<6% and <1%). The novel cyanide release is proposed to occur via 4,5-epoxidation on the fused imidazole ring, leading to ring opening and rearrangement along with the release of cyanide. The decyanated metabolites were identified and confirmed by synthetic standards, which supported the proposed mechanism. In dogs, glucuronidation to M19 was the major clearance mechanism, representing 59% of the dose in the bile of bile duct-cannulated (BDC) dogs and 19% of the dose in the urine of intact dogs. Additionally, M19 also represented 52% of drug related exposure in circulation in dogs. In comparison, in humans, navoximod was mainly cleared through glucuronidation to M28 and excreted in urine (60% of the dose). The differences in the metabolism and elimination observed in vivo were qualitatively recapitulated in vitro with liver microsomes, suspended hepatocytes, and cocultured primary hepatocytes. The striking species differences in regioselective glucuronidation is likely explained by the species differences in UGT1A9, which was mainly responsible for M28 formation in humans. SIGNIFICANCE STATEMENT: The results from this study demonstrated significant species differences in metabolism (especially glucuronidation) and elimination of navoximod among rats, dogs, and humans. The study also illustrated the mechanism of a novel cyanide release metabolism from the fused imidazo[5,1-a]isoindole ring. Such biotransformation should be kept in mind when working with imidazole-containing new chemical entities in drug discovery and development.


Subject(s)
Indoleamine-Pyrrole 2,3,-Dioxygenase , Isoindoles , Humans , Rats , Dogs , Animals , Indoleamine-Pyrrole 2,3,-Dioxygenase/analysis , Isoindoles/analysis , Cyanides/analysis , Species Specificity , Imidazoles , Biotransformation , Feces/chemistry
13.
Metab Eng ; 72: 150-160, 2022 07.
Article in English | MEDLINE | ID: mdl-35301124

ABSTRACT

Violacein, a blue-violet compound with a wide range of beneficial bioactivities, is an attractive product for microbial production. Currently, violacein production has been demonstrated in several sugar heterotrophs through metabolic engineering; however, the cost of production remains an obstacle for business ventures. To address this issue, the development of host strains that can utilize inexpensive alternative substrates to reduce production costs would enable the commercialization of violacein. In this study, we engineered a facultative methylotroph, Methylorubrum extorquens AM1, to develop a methanol-based platform for violacein production. By optimizing expression vectors as well as inducer concentrations, 11.7 mg/L violacein production was first demonstrated using methanol as the sole substrate. Considering that unidentified bottlenecks for violacein biosynthesis in the shikimate pathway of M. extorquens AM1 would be difficult to address using generic metabolic engineering approaches, random mutagenesis and site-directed mutagenesis were implemented, and a 2-fold improvement in violacein production was achieved. Finally, by co-utilization of methanol and acetate, a remarkable enhancement of violacein production to 118 mg/L was achieved. Our results establish a platform strain for violacein production from non-sugar feedstocks, which may contribute to the development of an economically efficient large-scale fermentation system for violacein production.


Subject(s)
Methanol , Methylobacterium extorquens , Acetates/metabolism , Indoles/metabolism , Methanol/metabolism , Methylobacterium extorquens/genetics , Methylobacterium extorquens/metabolism
14.
Chem Res Toxicol ; 35(8): 1400-1409, 2022 08 15.
Article in English | MEDLINE | ID: mdl-35833852

ABSTRACT

Acyl glucuronides (AGs) are common metabolites of carboxylic acid-containing compounds. In some circumstances, AGs are suspected to be involved in drug toxicity due to formation of acyl migration products that bind covalently to cellular components. The risk of this adverse effect has been found to be correlated with the chemical stability of the AG, and assays have been described that monitor acyl migration by liquid chromatography coupled with mass spectrometry (LC-MS). This analysis can be challenging as it requires baseline chromatographic separation of the unmigrated 1-ß-acyl glucuronide from the migrated isomers and thus needs to be individually optimized for each aglycone. Therefore, a high-throughput assay that eliminates LC method development is desirable. Herein, we report an improved acyl glucuronide stability assay based on the rate of 18O-incorporation from [18O] water, which is compatible with high-throughput bioanalytical LC-MS workflows. Synthetic AGs with shorter migration half-lives showed faster incorporation of 18O. The level of differential incorporation of 18O following a 24 h incubation correlates well with the migration tendency of AGs. This assay was developed further, exploring in situ generation of AGs by human hepatic microsomal fraction. The results from 18 in situ-formed acyl glucuronides were similar to those obtained using authentic reference standards. In this format, this new 18O-labeling method offers a simplified workflow, requires no LC method development or AG reference standard, and thus facilitates AG liability assessment in early drug discovery.


Subject(s)
Carboxylic Acids , Glucuronides , Chromatography, Liquid/methods , Glucuronides/metabolism , Humans , Isomerism , Mass Spectrometry
15.
J Proteome Res ; 20(11): 4925-4947, 2021 11 05.
Article in English | MEDLINE | ID: mdl-34582199

ABSTRACT

The soybean crop, Glycine max (L.) Merr., is consumed by humans, Homo sapiens, worldwide. While the respective bodies of literature and -omics data for each of these organisms are extensive, comparatively few studies investigate the molecular biological processes occurring between the two. We are interested in elucidating the network of protein-protein interactions (PPIs) involved in human-soybean allergies. To this end, we leverage state-of-the-art sequence-based PPI predictors amenable to predicting the enormous comprehensive interactome between human and soybean. A network-based analytical approach is proposed, leveraging similar interaction profiles to identify candidate allergens and proteins involved in the allergy response. Interestingly, the predicted interactome can be explored from two complementary perspectives: which soybean proteins are predicted to interact with specific human proteins and which human proteins are predicted to interact with specific soybean proteins. A total of eight proteins (six specific to the human proteome and two to the soy proteome) have been identified and supported by the literature to be involved in human health, specifically related to immunological and neurological pathways. This study, beyond generating the most comprehensive human-soybean interactome to date, elucidated a soybean seed interactome and identified several proteins putatively consequential to human health.


Subject(s)
Glycine max , Hypersensitivity , Humans , Proteome/genetics , Proteome/metabolism , Seeds/metabolism , Soybean Proteins/analysis , Glycine max/genetics , Glycine max/metabolism
16.
J Vis ; 21(7): 3, 2021 07 06.
Article in English | MEDLINE | ID: mdl-34251433

ABSTRACT

Visual search in natural scenes is a complex task relying on peripheral vision to detect potential targets and central vision to verify them. The segregation of the visual fields has been particularly established by on-screen experiments. We conducted a gaze-contingent experiment in virtual reality in order to test how the perceived roles of central and peripheral visions translated to more natural settings. The use of everyday scenes in virtual reality allowed us to study visual attention by implementing a fairly ecological protocol that cannot be implemented in the real world. Central or peripheral vision was masked during visual search, with target objects selected according to scene semantic rules. Analyzing the resulting search behavior, we found that target objects that were not spatially constrained to a probable location within the scene impacted search measures negatively. Our results diverge from on-screen studies in that search performances were only slightly affected by central vision loss. In particular, a central mask did not impact verification times when the target was grammatically constrained to an anchor object. Our findings demonstrates that the role of central vision (up to 6 degrees of eccentricities) in identifying objects in natural scenes seems to be minor, while the role of peripheral preprocessing of targets in immersive real-world searches may have been underestimated by on-screen experiments.


Subject(s)
Virtual Reality , Humans , Scotoma , Vision, Ocular , Visual Fields , Visual Perception
17.
Phys Chem Chem Phys ; 22(3): 1324-1332, 2020 Jan 21.
Article in English | MEDLINE | ID: mdl-31850419

ABSTRACT

Substituted phenols are known to readily react with the hydroxyl radical (OH˙), which is the most powerful atmospheric oxidant and is also most often used in advanced oxidation processes (AOP) for wastewater treatment. We report temperature-dependent (278.15-318.15 K) second order kinetic rate constants for the aqueous-phase reactions of OH˙ with phenol and four substituted phenols: catechol, phloroglucinol, pyrogallol and 3-methylcatechol, with the last two measured for the first time. The constructed Hammett plots for mono- and di-substituted phenols have the potential to be further applied for predicting the reaction rate constants of other substituted phenols at 298.15 K. This will significantly facilitate the optimization of AOP and improve the predictive capabilities of atmospheric multiphase models in the future. Moreover, an advancement in the understanding of the underlying mechanism, i.e. OH˙ addition to the aromatic ring is made by theoretical calculations at the M06-2X level. We demonstrate that the position of substituents on the aromatic ring is important for the [OH-phenol]˙ adduct formation, which is supported by the experiment and theoretical calculations. Adjacent and nonadjacent electron donor/acceptor substituents differently impact the interplay between the activation energy and entropy. We also show that explicit solvation has to be accounted for in theoretical models in order to explicitly describe the formation of the transition state.


Subject(s)
Hydroxyl Radical/chemistry , Phenols/chemistry , Temperature , Water Pollutants, Chemical/chemistry
18.
J Exp Child Psychol ; 194: 104782, 2020 06.
Article in English | MEDLINE | ID: mdl-32179293

ABSTRACT

In our daily lives, we rely on expectations of where to find objects in a scene. Every morning without conscious reflection, we find the milk in the refrigerator. How do these schemata develop during childhood? In the current study, we investigated the behavioral responses of 72 2- to 4-year-olds in two tasks that measured scene knowledge either directly by asking them to furnish a dollhouse or indirectly by observing their eye movements in a violation paradigm using scene photographs. In addition, we collected language acquisition measures for each child to investigate possible relations between the development of scene knowledge and language abilities. Results for both explicit and implicit measures indicated an increase of performance with age in terms of correct object placement relative to corresponding rooms/locations and a difference in first-pass dwell times between consistent and inconsistent objects. The consistency effect in eye movements was associated with shorter processing times for consistent objects, reflecting stronger predictions for objects in their familiar context/location. A reduction of first-pass dwell times to consistent objects was also predicted by the dollhouse performance measure of scene knowledge. Although strong links to language development could not be found, first indications are discussed together with possible improvements of future studies investigating such a link. In sum, our results imply that scene-related predictions effectively can influence implicit and explicit behavior by 4 years of age at the latest, allowing optimized attention allocation in scenes.


Subject(s)
Child Development/physiology , Pattern Recognition, Visual/physiology , Psychomotor Performance/physiology , Space Perception/physiology , Child, Preschool , Eye Movement Measurements , Female , Humans , Male
19.
Int J Mol Sci ; 21(9)2020 Apr 30.
Article in English | MEDLINE | ID: mdl-32366036

ABSTRACT

Riboswitches and toehold switches are considered to have potential for implementation in various fields, i.e., biosensing, metabolic engineering, and molecular diagnostics. The specific binding, programmability, and manipulability of these RNA-based molecules enable their intensive deployments in molecular detection as biosensors for regulating gene expressions, tracking metabolites, or detecting RNA sequences of pathogenic microorganisms. In this review, we will focus on the development of riboswitches and toehold switches in biosensing and molecular diagnostics. This review introduces the operating principles and the notable design features of riboswitches as well as toehold switches. Moreover, we will describe the advances and future directions of riboswitches and toehold switches in biosensing and molecular diagnostics.


Subject(s)
Biosensing Techniques/methods , Riboswitch/physiology , Pathology, Molecular/methods , Riboswitch/genetics
20.
Int J Mol Sci ; 21(6)2020 Mar 16.
Article in English | MEDLINE | ID: mdl-32188055

ABSTRACT

Plant growth-promoting rhizobacteria play vital roles not only in plant growth, but also in reducing biotic/abiotic stress. Sphingomonas panacis DCY99T is isolated from soil and root of Panax ginseng with rusty root disease, characterized by raised reddish-brown root and this is seriously affects ginseng cultivation. To investigate the relationship between 159 sequenced Sphingomonas strains, pan-genome analysis was carried out, which suggested genomic diversity of the Sphingomonas genus. Comparative analysis of S. panacis DCY99T with Sphingomonas sp. LK11 revealed plant growth-promoting potential of S. panacis DCY99T through indole acetic acid production, phosphate solubilizing, and antifungal abilities. Detailed genomic analysis has shown that S. panacis DCY99T contain various heavy metals resistance genes in its genome and the plasmid. Functional analysis with Sphingomonas paucimobilis EPA505 predicted that S. panacis DCY99T possess genes for degradation of polyaromatic hydrocarbon and phenolic compounds in rusty-ginseng root. Interestingly, when primed ginseng with S. panacis DCY99T during high concentration of iron exposure, iron stress of ginseng was suppressed. In order to detect S. panacis DCY99T in soil, biomarker was designed using spt gene. This study brings new insights into the role of S. panacis DCY99T as a microbial inoculant to protect ginseng plants against rusty root disease.


Subject(s)
Drug Tolerance/genetics , Genome, Bacterial , Iron/metabolism , Panax/microbiology , Sphingomonas/genetics , Sphingomonas/physiology , DNA, Bacterial , Genes, Bacterial/genetics , Genome Size , Hydroxybenzoates , Iron/toxicity , Metals, Heavy , Plant Development , Plant Roots/microbiology , Soil Microbiology , Sphingomonas/drug effects , Sphingomonas/isolation & purification , Stress, Physiological
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