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Nutrition, Metabolism, and... Jul 2021Insufficient dietary fiber (DF) intake is associated with increased blood pressure (BP) and the mode of action is unclear. The intake of DF supplements by participants... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND AND AIMS
Insufficient dietary fiber (DF) intake is associated with increased blood pressure (BP) and the mode of action is unclear. The intake of DF supplements by participants in previous interventional studies was still far below the amount recommended by the World Health Organization. Therefore, this study aims to explore the effect of supplementing relatively sufficient DF on BP and gut microbiota in patients with essential hypertension (HTN).
METHODS AND RESULTS
Fifty participants who met the inclusion criteria were randomly divided into the DF group (n = 25) and control group (n = 25). All the participants received education on regular dietary guidance for HTN. In addition to dietary guidance, one bag of oat bran (30 g/d) supplement (containing DF 8.9 g) was delivered to the DF group. The office BP (oBP), 24 h ambulatory blood pressure, and gut microbiota were measured at baseline and third month. After intervention, the office systolic blood pressure (oSBP; P < 0.001) and office diastolic blood pressure (oDBP; P < 0.028) in the DF group were lower than those in the control group. Similarly, the changes in 24hmaxSBP (P = 0.002), 24hmaxDBP (P = 0.001), 24haveSBP (P < 0.007), and 24haveDBP (P = 0.008) were greater in the DF group than in the control group. The use of antihypertensive drugs in the DF group was significantly reduced (P = 0.021). The β diversity, including Jaccard (P = 0.008) and Bray-Curtis distance (P = 0.004), showed significant differences (P < 0.05) between two groups by the third month. The changes of Bifidobacterium (P = 0.019) and Spirillum (P = 0.006) in the DF group were significant.
CONCLUSIONS
Increased DF (oat bran) supplement improved BP, reduced the amount of antihypertensive drugs, and modulated the gut microbiota.
TRIAL REGISTRATION NUMBER
ChiCTR1900024055.
Topics: Adult; Avena; Bifidobacterium; Blood Pressure; Blood Pressure Monitoring, Ambulatory; China; Dietary Fiber; Dysbiosis; Edible Grain; Essential Hypertension; Female; Gastrointestinal Microbiome; Humans; Male; Middle Aged; Nutritive Value; Prospective Studies; Spirillum; Time Factors; Treatment Outcome
PubMed: 34090773
DOI: 10.1016/j.numecd.2021.04.013 -
Application of enhanced assimilable organic carbon method across operational drinking water systems.PloS One 2019Assimilable organic carbon (AOC) is known to correlate with microbial growth, which can consequently degrade drinking water quality. Despite this, there is no...
Assimilable organic carbon (AOC) is known to correlate with microbial growth, which can consequently degrade drinking water quality. Despite this, there is no standardised AOC test that can be applied to drinking water distribution systems (DWDS). Herein we report the development of a quick, robust AOC that incorporates known strains Pseudomonas fluorescens strain P-17 and Spirillum strain NOX, a higher inoculum volume and enumeration using flow cytometry to generate a quicker (total test time reduced from 14 to 8 days), robust method. We apply the developed AOC test to twenty drinking water treatment works (WTW) to validate the method reproducibility and resolution across a wide range of AOC concentrations. Subsequently, AOC was quantified at 32 sample points, over four DWDS, for a year in order to identify sinks and sources of AOC in operative networks. Application of the developed AOC protocol provided a previously unavailable insight and novel evidence of pipes and service reservoirs exhibiting different AOC and regrowth behaviour. Observed correlations between AOC and microbial growth highlight the importance of monitoring AOC as an integral part of managing drinking water quality at the consumers tap.
Topics: Carbon; Drinking Water; Flow Cytometry; Organic Chemicals; Pseudomonas fluorescens; Reproducibility of Results; Spirillum; Water Microbiology; Water Purification; Water Quality
PubMed: 31809502
DOI: 10.1371/journal.pone.0225477 -
International Journal of Systematic and... Feb 2020A Gram-stain-negative, strictly aerobic, non-motile and non-pigmented spirillum, designated strain LZ-5, was isolated from cultures of the paralytic shellfish poisoning...
A Gram-stain-negative, strictly aerobic, non-motile and non-pigmented spirillum, designated strain LZ-5, was isolated from cultures of the paralytic shellfish poisoning (PSP) toxin-producing marine dinoflagellate LZT09 collected from the Zhoushan sea area in the East China Sea during an algal bloom. The isolate grew at 4-40 °C (optimum, 25-33 °C) and pH 5.0-9.0 (optimum, 7.5) in the presence of 0.5-10 % (w/v) NaCl (optimum, 4.0 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain LZ-5 clearly belonged to the genus of the family . Strain LZ-5 shared highest 16S rRNA gene sequence similarity with EL-105 (98.9 %), HK-33 (97.2 %) CPA1 (96.8 %), YIM-Y25 (96.8 %) and IMCC 4453 (95.1 %). The average nucleotide identity and DNA-DNA hybridization between strain LZ-5 and the two most closely related strains, EL-105 and HK-33, were 82.2 and 19.3 %, and 72.2 and 13.2 %, respectively. The predominant respiratory quinone of strain LZ-5 was Q-8, and the major fatty acids were summed feature 8 (Cω7 and/or Cω6), summed feature 3 (Cω7 and/or Cω6) and C. The polar lipids of strain LZ-5 were diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylcholine (PC), glycolipid (GL), two unidentified glycophospholipids (GPLs), three unidentified aminophospholipids (APLs) and two unidentified lipids. The genomic DNA G+C content was 57.2 mol%. On the basis of this polyphasic characterization, strain LZ-5 represents a novel species of the genus , for which the name sp. nov. is proposed. The type strain is LZ-5 (=KCTC 62460=CCTCC AB2017232).
Topics: Bacterial Typing Techniques; Base Composition; China; DNA, Bacterial; Dinoflagellida; Eutrophication; Fatty Acids; Gammaproteobacteria; Nucleic Acid Hybridization; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Ubiquinone
PubMed: 31671052
DOI: 10.1099/ijsem.0.003832 -
ACS Applied Materials & Interfaces Jan 2023Magnetotactic bacteria AMB-1 have been cultured using three different media: magnetic spirillum growth medium with Wolfe's mineral solution (MSGM + W), magnetic...
Magnetotactic bacteria AMB-1 have been cultured using three different media: magnetic spirillum growth medium with Wolfe's mineral solution (MSGM + W), magnetic spirillum growth medium without Wolfe's mineral solution (MSGM - W), and flask standard medium (FSM). The influence of the culture medium on the structural, morphological, and magnetic characteristics of the magnetosome chains biosynthesized by these bacteria has been investigated by using transmission electron microscopy, X-ray absorption spectroscopy, and X-ray magnetic circular dichroism. All bacteria exhibit similar average size for magnetosomes, 40-45 nm, but FSM bacteria present slightly longer subchains. In MSGM + W bacteria, Co ions present in the medium substitute Fe ions in octahedral positions with a total Co doping around 4-5%. In addition, the magnetic response of these bacteria has been thoroughly studied as functions of both the temperature and the applied magnetic field. While MSGM - W and FSM bacteria exhibit similar magnetic behavior, in the case of MSGM + W, the incorporation of the Co ions affects the magnetic response, in particular suppressing the Verwey (∼105 K) and low temperature (∼40 K) transitions and increasing the coercivity and remanence. Moreover, simulations based on a Stoner-Wolhfarth model have allowed us to reproduce the experimentally obtained magnetization versus magnetic field loops, revealing clear changes in different anisotropy contributions for these bacteria depending on the employed culture medium. Finally, we have related how these magnetic changes affect their heating efficiency by using AC magnetometric measurements. The obtained AC hysteresis loops, measured with an AC magnetic field amplitude of up to 90 mT and a frequency, , of 149 kHz, reveal the influence of the culture medium on the heating properties of these bacteria: below 35 mT, MSGM - W bacteria are the best heating mediators, but above 60 mT, FSM and MSGM + W bacteria give the best heating results, reaching a maximum heating efficiency or specific absorption rate (SAR) of SAR/ ≈ 12 W g kHz.
Topics: Magnetospirillum; Magnetosomes; Hyperthermia, Induced; Magnetic Phenomena
PubMed: 36563339
DOI: 10.1021/acsami.2c18435 -
The Yale Journal of Biology and Medicine Jun 2021Rat-bite fever is an over-looked, global zoonotic disease that has a mortality rate of up to 13%, if untreated. Historically, this rat-borne disease has been attributed...
Rat-bite fever is an over-looked, global zoonotic disease that has a mortality rate of up to 13%, if untreated. Historically, this rat-borne disease has been attributed to one of two causative agents, or . Given the confirmed presence of multiple invasive host species, high rat densities in urban, informal human settlements and increasing reports of rat bites in South Africa, we undertook a retrospective assessment of in rats sampled from 16 urban sites, in Gauteng, the smallest but most populous Province in South Africa. Using a multi-gene PCR-sequencing approach, we confirmed presence in 50.9% of oral swabs from three rat species and the presence of two species, and . The two members of the cryptic species complex ( and ), which are morphologically indistinguishable from each other, had markedly different colonization rates. Whereas 48.6% of rats from this species complex were -positive, only 32.3% of were positive compared to 61.5% had an intermediate prevalence of 55.6%. Phylogenetic analysis of four gene regions (16S rRNA, , , ) identified two discrete lineages; occurred exclusively in , and was restricted to the two members of the species complex; this represents the first report of in . These results highlight a largely overlooked zoonotic threat posed by invasive rats and confirm the presence of two discrete and potentially host-specific lineages in South Africa.
Topics: Animals; Introduced Species; Phylogeny; Prevalence; RNA, Ribosomal, 16S; Rat-Bite Fever; Rats; Retrospective Studies; South Africa; Streptobacillus
PubMed: 34211343
DOI: No ID Found -
MSystems Oct 2019The evolution of microbial magnetoreception (or magnetotaxis) is of great interest in the fields of microbiology, evolutionary biology, biophysics, geomicrobiology, and...
The evolution of microbial magnetoreception (or magnetotaxis) is of great interest in the fields of microbiology, evolutionary biology, biophysics, geomicrobiology, and geochemistry. Current genomic data from magnetotactic bacteria (MTB), the only prokaryotes known to be capable of sensing the Earth's geomagnetic field, suggests an ancient origin of magnetotaxis in the domain Vertical inheritance, followed by multiple independent magnetosome gene cluster loss, is considered to be one of the major forces that drove the evolution of magnetotaxis at or above the class or phylum level, although the evolutionary trajectories at lower taxonomic ranks (e.g., within the class level) remain largely unstudied. Here we report the isolation, cultivation, and sequencing of a novel magnetotactic spirillum belonging to the genus ( sp. strain SH-1) within the class The complete genome sequence of sp. strain SH-1 revealed an unexpected duplication event of magnetosome genes within the operon, a group of genes essential for magnetosome biomineralization and magnetotaxis. Intriguingly, further comparative genomic analysis suggests that the duplication of genes is a common feature in the genomes of alphaproteobacterial MTB. Taken together, with the additional finding that gene duplication appears to have also occurred in some magnetotactic members of the , our results indicate that gene duplication plays an important role in the evolution of magnetotaxis in the and perhaps the domain A diversity of organisms can sense the geomagnetic field for the purpose of navigation. Magnetotactic bacteria are the most primitive magnetism-sensing organisms known thus far and represent an excellent model system for the study of the origin, evolution, and mechanism of microbial magnetoreception (or magnetotaxis). The present study is the first report focused on magnetosome gene cluster duplication in the , which suggests the important role of gene duplication in the evolution of magnetotaxis in the and perhaps the domain A novel scenario for the evolution of magnetotaxis in the is proposed and may provide new insights into evolution of magnetoreception of higher species.
PubMed: 31662428
DOI: 10.1128/mSystems.00315-19 -
Journal of Hazardous Materials Jun 2024Macrophyte rhizospheric dissolved organic matter (ROM) served as widespread abiotic components in aquatic ecosystems, and its effects on antibiotic residues and...
Macrophyte rhizospheric dissolved organic matter (ROM) served as widespread abiotic components in aquatic ecosystems, and its effects on antibiotic residues and antibiotic resistance genes (ARGs) could not be ignored. However, specific influencing mechanisms for ROM on the fate of antibiotic residues and expression of ARGs still remained unclear. Herein, laboratory hydroponic experiments for water lettuce (Pistia stratiotes) were carried out to explore mutual interactions among ROM, sulfamethoxazole (SMX), bacterial community, and ARGs expression. Results showed ROM directly affect SMX concentrations through the binding process, while CO and N-H groups were main binding sites for ROM. Dynamic changes of ROM molecular composition diversified the DOM pool due to microbe-mediated oxidoreduction, with enrichment of heteroatoms (N, S, P) and decreased aromaticity. Microbial community analysis showed SMX pressure significantly stimulated the succession of bacterial structure in both bulk water and rhizospheric biofilms. Furthermore, network analysis further confirmed ROM bio-labile compositions as energy sources and electron shuttles directly influenced microbial structure, thereby facilitating proliferation of antibiotic resistant bacteria (Methylotenera, Sphingobium, Az spirillum) and ARGs (sul1, sul2, intl1). This investigation will provide scientific supports for the control of antibiotic residues and corresponding ARGs in aquatic ecosystems.
Topics: Sulfamethoxazole; Anti-Bacterial Agents; Drug Resistance, Microbial; Bacteria; Genes, Bacterial; Rhizosphere; Water Pollutants, Chemical; Microbiota; Biofilms
PubMed: 38653136
DOI: 10.1016/j.jhazmat.2024.134351 -
Huan Jing Ke Xue= Huanjing Kexue Aug 2021Ammonia nitrogen (NH-N) removal capacities of the A/O and inverted A/O processes were analyzed with the same inlet and parallel operation during winter. When the...
Ammonia nitrogen (NH-N) removal capacities of the A/O and inverted A/O processes were analyzed with the same inlet and parallel operation during winter. When the operating water temperature was 14℃, the inverted A/O process exhibited lower NH-N removal from the volumetric load[0.13 kg ·(m ·d)vs. 0.29 kg ·(m ·d)] and a lower ammonia oxidation rate (AOR)[0.07 kg ·(kg ·d) vs. 0.11 kg ·(kg ·d)] than the A/O process, whereas the two processes exhibited similar performance at 26℃.The quantitative results for the ammonia oxidizing bacteria (AOB) population were almost the same in the two parallel processes (3.2%±0.24% for the inverted A/O process and 3.4%±0.31% for the A/O process). Clone library analysis showed that at low temperatures, the inverted A/O process had a lower capacity for ammonia nitrogen removal than A/O process. This is because the particular AOB species[spirillum ()] facilitated the slower AOR type (K-growth strategy) of nitrosation in the inverted A/O process, whereas in the A/O process, the faster AOR type (r-growth strategy) of nitrosation was facilitated by bacterium (). At 26℃, the dominant species in the two processes were . Through comprehensive analysis of the pollutants during the removal process, we found that although temperature is the leading cause of AOB advantage in species succession, the changes in the inverted A/O process structure, caused by the aerobic unit, resulted in high COD load and high NH-N concentration, which were unfavorable for the growth of AOB. This shows that under conventional sewage conditions, the K-growth strategy is advantageous for the AOB species. Therefore, the structure of the inverted A/O process for heterotrophic bacteria (phosphorus accumulating bacteria and denitrifying bacteria) indirectly affects the population distribution and succession of autotrophic ammonia-oxidizing bacteria, through COD load and other factors, thereby leading to weakened nitrification capacity at low temperatures.
Topics: Ammonia; Bioreactors; Denitrification; Nitrification; Nitrogen; Oxidation-Reduction; Sewage
PubMed: 34309273
DOI: 10.13227/j.hjkx.202011157