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1.
Seizure ; 86: 102-108, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33588305

RESUMO

PURPOSE: This study investigated the role of one-stage stereo-array radiofrequency thermocoagulation based on stereotactic electroencephalography in the treatment of pediatric hypothalamic hamartomas. METHODS: We analyzed the clinical data of 28 patients with hypothalamic hamartoma. A high-density focal stereo-array electrode implantation strategy was adopted. Stereotactic electroencephalography guided bipolar coagulations were performed between two contiguous contacts of the same electrode, or between two adjacent contacts of different electrodes. Patients with hypothalamic hamartoma were divided into two groups based on hamartoma size (maximum diameter < 15 mm vs maximum diameter ≥ 15 mm). Numbers of implanted electrodes and contacts used for thermocoagulation were documented. Seizure outcome was evaluated according to Engel's classification. RESULTS: Surgical procedures were well tolerated and no repeated surgery was performed. The median number of electrodes implanted in the two groups was significantly different (p = 0.0009), as well as the median number of contacts where radiofrequency thermocoagulation was applied (p = 0.0006). Moreover, the number of implanted electrodes and contacts used for thermocoagulation were positively correlated with the hamartoma volume (Spearman's rho = 0.7074, p<0.0001 and Spearman's rho = 0.7435, p<0.0001, respectively). The overall seizure-free rate was 82.1 %, with 92.9 % of the patients having favorable outcomes for at least 12 months of follow-up. Seizure outcomes between two groups were not statistically significant (p = 0.3138). CONCLUSION: One-stage high-density focal stereo-array stereotactic electroencephalography guided radiofrequency thermocoagulation using cross-bonded electrode contacts for ablation range expansion is a safe and effective surgical approach for children with hypothalamic hamartoma.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33608286

RESUMO

The Asgard superphylum is a deeply branching monophyletic group of Archaea, recently described as some of the closest relatives of the eukaryotic ancestor. The wide application of genomic analyses from metagenome sequencing has established six distinct phyla, whose genomes encode for diverse metabolic capacities and play important biogeochemical and ecological roles in marine sediments. Here, we describe two metagenome-assembled genomes (MAGs) recovered from deep marine sediments off Costa Rica margin, defining a novel lineage phylogenetically married to Thorarchaeota, as such we propose the name "Sifarchaeota" for this phylum. The two "Sifarchaeota" MAGs encode for an anaerobic pathway for methylotrophy enabling the utilization of C1-C3 compounds (methanol and methylamines) to synthesize acetyl CoA. The MAGs showed a remarkable saccharolytic capabilities compared to other Asgard lineages and encoded for diverse classes of carbohydrate active enzymes (CAZymes) targeting different mono-, di- and oligosaccharides. Comparative genomic analysis based on the full metabolic profiles of different Asgard lineages revealed the close relation between "Sifarchaeota" and Odinarchaeota MAGs, which suggested similar metabolic potentials and ecological roles. Furthermore, we identified multiple HGT events from different bacterial donors within "Sifarchaetoa" MAGs, which hypothetically expanded "Sifarchaeota" capacities for substrate utilization, energy production and niche adaptation.Importance The exploration of deep marine sediments has unearthed many new lineages of microbes. The finding of this novel phylum of Asgard archaea is important since understanding the diversity and evolution of Asgard archaea may inform also about the evolution of eukaryotic cells. The comparison of metabolic potentials of the Asgard archaea can help inform about selective pressures the lineages have faced during evolution.

3.
J Clin Anesth ; 69: 110150, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33418429

RESUMO

STUDY OBJECTIVE: This study aimed to evaluate the effects of low versus high mean arterial pressure (MAP) levels on the incidence of postoperative delirium during non-cardiothoracic surgery in older patients. DESIGN: Multicenter, randomized, parallel-controlled, open-label, and assessor-blinded clinical trial. SETTING: University hospital. PATIENTS: Three hundred twenty-two patients aged ≥65 with an American Society of Anesthesiologists physical status of I-II who underwent non-cardiothoracic surgery with general anaesthesia. INTERVENTIONS: Participants were randomly assigned into a low-level MAP (60-70 mmHg) or high-level MAP (90-100 mmHg) group during general anaesthesia. The study was conducted from November 2016 to February 2020. Participants were older patients having non-cardiothoracic surgery. The follow-up period ranged from 1 to 7 days after surgery. The primary outcome was the incidence of postoperative delirium. MAIN RESULTS: In total, 322 patients were included and randomized; 298 completed in-hospital delirium assessments [median (interquartile range) age, 73 (68-77) years; 173 (58.1%) women]. Fifty-four (18.1%) patients total, including 36 (24.5%) and 18 (11.9%) in the low-level and high-level MAP groups [relative risk (RR) 0.48, 95% confidence interval (CI) 0.25 to 0.87, P = 0.02], respectively, experienced postoperative delirium. The adjusted RR was 0.34 (95% CI 0.16 to 0.70, P < 0.01) in the multiple regression analysis. High-level MAP was associated with a shorter delirium span and a higher intraoperative urine volume than low-level MAP. CONCLUSIONS: In older patients during non-cardiothoracic surgery, high-level blood pressure management might help reduce the incidence of postoperative delirium.

4.
Langmuir ; 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33401905

RESUMO

In this paper, an optofluidic phase modulator based on dielectrowetting is designed and fabricated to adjust the optical phase. Two liquids are filled in the device, and a transparent sheet is employed at the liquid interface to keep the interface flat. When different voltages are applied to the modulator, the flat interface moves up and down, leading to the variation of the optical phase. A theoretical model is constructed to predict the optical phase shift quantitatively, and the phase regulation ability is also tested experimentally. Our modulator realizes continuous adjustment of the optical phase in a certain range by the operation of voltage adjustment. When the voltage is increased to 150 V, the optical phase modulation range of our proposed modulator can reach 9.366 π.

5.
Neuroreport ; 32(2): 88-98, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33395185

RESUMO

BACKGROUND: Increasing studies have suggested that microRNAs (miRNAs) contribute to the occurrence and development of glioblastoma. MiR-522-3p is a novel miRNA, which has been found to modulate tumorigenesis and tumor progression. However, its pathological role and functional mechanism in glioblastoma remain elusive at present. METHOD: The miR-522-3p expression in glioblastoma and adjacent normal tissues, human fetal astrocyte HA1800, and glioblastoma cell lines was detected by reverse transcription-PCR. The proliferation, migration, and invasion were detected through Cell Counting Kit-8 (CCK8) and Transwell assay, and apoptosis was calculated through flow cytometry. The downstream target of miR-522-3p was analyzed through bioinformatics, and the correlation between miR-522-3p and secreted frizzled-related protein 2 (SFRP2) was verified through dual-luciferase reporter assay and RNA immunoprecipitation (RIP) experiment. Besides, western blot was conducted to test the level of SFRP2 and the Wnt/ß-catenin pathway. RESULTS: MiR-522-3p was overexpressed in glioblastoma tissues compared with that in normal tissues, and the inhibition of miR-522-3p reduced cell proliferation, migration, and invasion and promoted apoptosis in glioblastoma. Bioinformatics revealed that SFRP2 was an essential downstream target of miR-522-3p, and it inhibited the malignant biological behaviors induced by miR-522-3p and inactivated the Wnt/ß-catenin pathway. CONCLUSION: MiR-522-3p is an oncogene in glioblastoma by targeting SFRP2 through the Wnt/ß-catenin pathway.

6.
BMC Anesthesiol ; 21(1): 6, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33407139

RESUMO

BACKGROUND: Coblation is a novel technique in respect of treating idiopathic trigeminal neuralgia. We aimed to identify the efficacy and complications between radiofrequency thermocoagulation (RFT) and coblation for V2/V3 idiopathic trigeminal neuralgia (ITN) and investigate the risk factors associated with postoperative facial numbness. METHODS: We retrospectively reviewed our cohort of 292 patients who had undergone RFT or coblation for V2/V3 ITN. The characteristics of the baseline were collected before surgery. Pain scores, the degree of facial numbness and other complications were evaluated at discharge and 1 month, 3 months, 6 months and 12 months after surgery. RESULTS: Postoperative pain intensity was apparently alleviated in both groups. The initial and 12-months remission rates were 94.0 and 75.3% in coblation group compared with 96.9 and 78.4% in RFT group (P = 0.462, P = 0.585). The degree of postoperative facial numbness tended to be more severe in RFT group at discharge, 1 month, 6 months and 12 months (P = 0.006, P = 0.026, P = 0.004, P = 0.003). Factors significantly associated with more severe facial numbness were procedure of RFT (OR = 0.46, 95%CI: 0.28-0.76, P = 0.002), history of previous RFT at the affected side (OR = 2.33, 95%CI: 1.21-4.48, P = 0.011), and ITN with concomitant continuous pain (OR = 0.36, 95%CI: 0.18-0.71, P = 0.004). CONCLUSION: Coblation could reduce the degree of postoperative facial numbness for ITN, and the efficacy was no less effective than RFT. History of previous RFT at the affected side, procedure of RFT, ITN with concomitant continuous pain was identified as significant factors of the development of postoperative facial numbness.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33433655

RESUMO

PURPOSE: The purpose of this meta-analysis was to assess the associations between inflammatory bowel disease (IBD) and risk of the gastric, small bowel and colorectal cancer. METHODS: We searched the PubMed and Web of Science for observational studies published before June 2020, and the quality of each included study was evaluated according to the Newcastle-Ottawa-Scale. RESULTS: Twenty-six studies comprising 531 449 IBD patients and more than 65 million reference individuals were included. Although IBD was significantly associated with 67% increased risk of the total gastric, small bowel and colorectal cancer. After stratifying by cancer location, IBD mainly increased the risk of intestinal cancer instead of gastric cancer. Furthermore, Crohn's disease (CD) significantly increased the risk of both small bowel cancer and colorectal cancer, while ulcerative colitis (UC) only increased the risk of colorectal cancer. In subgroup analysis, associations between IBD and risk of total gastric, small bowel and colorectal cancer were similar between male and female, except for that male IBD patients but not female had a significantly higher risk of small bowel cancer. Additionally, IBD patients in different geographical areas had different associations with risk of various gastrointestinal tract cancers. CONCLUSIONS: IBD is mainly associated with increased risk of cancers in the lower gastrointestinal tract, including small bowel cancer and colorectal cancer. Because studies about the association between IBD and risk of gastric cancer and the populations in Asia are limited, more observational studies are required in the future.

8.
Interv Neuroradiol ; : 1591019920987913, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33435781

RESUMO

BACKGROUND: Basilar artery perforator aneurysms (BAPAs) are rare. Traditional surgical clipping and endovascular coiling have proven to be challenging. We present three patients treated with endovascular electrothrombosis and describe the characteristics of this new approach. METHODS: Three patients presented with subarachnoid hemorrhages (SAHs). Cerebral angiography identified BAPAs. Endovascular electrothrombosis was performed after obtaining informed consent. We placed the microwire into the sac of the aneurysms through the microcatheter and connected its proximal tip to the Solitaire stent detachment system. Electrothrombosis was conducted using 1.0 mA current. RESULTS: Two aneurysms were successfully occluded without treatment-related complication. The third one failed and converted to endovascular coiling using a 1.3-F microcatheter. The patient suffered brainstem infarction and finally died of severe SAH. At follow-up, the two patients were neurologically intact and angiography showed total occlusion of both aneurysms. CONCLUSION: Endovascular electrothrombosis might be a potential alternative to traditional treatment for BAPAs. Close follow-up with caution should be mandatory. More research is needed to confirm its safety and efficacy.

9.
Appl Opt ; 60(2): 459-464, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33448972

RESUMO

A difference-fitting method is proposed to mitigate the low frequency drift of a phase-sensitive optical time domain reflectometry (Φ-OTDR) system caused by laser phase noise. The effective difference region for phase demodulation is theoretically analyzed and experimentally verified, which should be greater than the convolution of the spatial resolution and the length of disturbed optical fiber. Then, a median-fitting algorithm is used to obtain the phase noise of the differential region. The vibration signal of 0.2 Hz is first demodulated with the SNR of 41.79 dB on the optical fiber of 11 km. The low-frequency vibration signals of 0.05 Hz and 0.02 Hz are then successfully restored by using the difference-fitting method, which can effectively eliminate the influence of low frequency drift.

10.
Sci Total Environ ; 760: 144307, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33341637

RESUMO

Developing robust and effective adsorbent for removing ubiquitous pharmaceutical diclofenac (DCF) from the aquatic environment is vitally important for environmental safety. Hence, a novel chitosan-based multilayer adsorbent (FCS-PD) with magnetic separation ability and surface functionality was successfully assembled, which had countless potential for removing contaminants from water. A series of instrumental technologies were performed to demonstrate the physicochemical properties of FCS-PD. Its adsorption performance toward DCF removal was comprehensively evaluated in synthetic water and surface water. The effects of microplastics, inorganic ions and humic acid on the adsorption were investigated. The maximum adsorption capacity of FCS-PD was calculated as 434.78 mg/g under neutral conditions, exhibiting superior adsorption performance than most reported adsorbents. The DCF in surface water was practically removed at low concentration (50 µg/L). FCS-PD presented a multistage kinetics controlled by chemisorption and intraparticle diffusion, which was emphasized by the pseudo-second-order kinetic and intra-particle diffusion analysis. After five cycles of adsorption and regeneration, the adsorption capacity only decreased by 9.9%, indicating the satisfactory regeneration of FCS-PD. The analysis of high-resolution X-ray photoelectron spectroscopic (XPS) and Fourier transform infrared spectroscopy (FTIR) revealed that the quaternary ammonium groups on the outer layer and the amino and hydroxyl groups on the chitosan layer are involved in the capture of DCF under electrostatic force and hydrogen bonding.

11.
J Hazard Mater ; 403: 123728, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32853890

RESUMO

The release of highly toxic tellurite into the aquatic environment poses significant environmental risks. The acceleration mechanism and tellurium nanorods (TeNPs) characteristics with bioavailable ferric citrate (Fe(III)) were investigated in the tellurite (Te(IV)) bioreduction. Experiments showed that 5 mM Fe(III) increased the Te(IV) bioreduction rate from 0 to 12.40 mg/(L·h). Cyclic voltammetry, electrochemical impedance spectroscopy and Tafel were used to investigate electron transfer during Te(IV) bioreduction. NADH production (electron production) was significantly enhanced to 138% by Fe(III). Meanwhile Fe(III) stimulated the increase of cytochrome c, resulting in increased electron transport system activity. In addition, Fe(III) facilitated the secretion of extracellular polymeric substances (EPS) and reduced cell membrane permeability, thus reducing the toxicity of Te(IV) to cells. The increase of ATP provided energy for the metabolic process of Te(IV) bioreduction, playing an active role in cell activity. Based on the above analysis, the acceleration mechanism of Fe(III) on Te(IV) bioreduction was proposed from the aspects of electron generation, electron transfer and energy level. Zeta potential and FT-IR spectra indicated that the stability of TeNPs contributed to the covered EPS. This study provides further understanding the acceleration mechanism of Te(IV) bioreduction and promising strategy for improving the stability of TeNPs.

12.
Appl Opt ; 60(1): 125-134, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33362080

RESUMO

Imaging the high-precision magnetic distribution generated by the surface current of chips and chip-like structures is an important way to measure thermal parameters of core components. Based on a high-concentration nitrogen-vacancy color center ensemble in diamond, the imaging magnetic field distribution is performed in a wide-field microscope. The magnetic vector detection and reduction model is verified first with continuous wave optical detection of magnetic resonance technology. By systematically measuring the distribution of the electromagnetic field generated on the surface of the micro-wire under different microwave power and different laser power conditions, the imaging quality of the wide-field imaging system can be optimized by adjusting the experimental parameters. Then, the electromagnetic field distribution imaging on the wire surface under different current intensities is obtained. In this way, accurate measurement and characterization of the magnetic distribution on the surface of the micro-wire is realized. Finally, at the field of view in the range of 480µm×270µm, the magnetic intensity is an accurate characterization in 0.5-10 Gs, and the magnetic detection sensitivity can be increased from 100 to 20µT/Hz1/2. The results show the accurate magnetic distribution imaging for chips and chip-like structures, which provide a new method for chip function detection and fault diagnosis based on precision quantum measurement technology.

13.
ACS Appl Mater Interfaces ; 13(1): 755-764, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33373204

RESUMO

Recently, metal-organic framework (MOF)-based electrospun fibers have attracted considerable attention as adsorbents for organic contaminant removal from water. To prepare these fibers, two common strategies including blending electrospinning and surface coating are employed. However, fibers obtained from the two strategies still have some disadvantages, such as adsorption site blockage and unstable loading. Here, we constructed interconnected mesopores in the electrospun zeolitic imidazolate framework-8 (ZIF-8)/polyacrylonitrile (PAN) fibers with the assistance of poly(vinylpyrrolidone) to expose more adsorption sites of ZIF-8 and make ZIF-8 more stable. Moreover, the mesopores could also enhance the diffusion of contaminant molecules and create MOF-polymer interfaces in the fiber, which improve the adsorption rate and adsorption capacity, respectively. The obtained fibers were used to adsorb antibiotic tetracycline from water. Benefiting from the mesoporous adsorption channels and the MOF-polymer interface, porous ZIF-8/PAN fibers showed faster adsorption kinetics than ZIF-8/PAN blending fibers and larger adsorption capacity than ZIF-8-coated PAN fibers and ZIF-8/PAN blending fibers. The maximum adsorption capacity of porous ZIF-8/PAN fibers was 885.24 mg/g, which is close to that of pure ZIF-8. After 10 adsorption-desorption cycles, the removal efficiency was still above 97%. In addition, porous ZIF-8/PAN fibers could act as the membrane adsorbents to dynamically separate tetracycline with a treated capacity of 9.93 × 103 bed volumes. These results demonstrate that our prepared porous ZIF-8/PAN fibers have great potential in antibiotic drug removal.

14.
Eur J Med Chem ; : 112903, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33256948

RESUMO

A growing number of reports suggested that the inhibitor targeting cyclin-dependent kinases (CDK) 2/4/6 can act as a more feasible chemotherapy strategy. In the present paper, a novel PROTAC molecule was developed based on the structure of Ribociclib's derivative. In malignant melanoma cells, the degrader can not only degrade CDK 2/4/6 simultaneously and effectively, but also remarkably induce cell cycle arrest and apoptosis of melanoma cells. Moreover, PROTAC molecules with CRBN ligands always have poor oral bioavailability. We developed the orally bioavailable prodrug for the first time. It would provide general solution for oral administration of the PROTAC molecules, derived from CRBN ligands, for animal test conveniently.

15.
Trends Biochem Sci ; 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33272784

RESUMO

In eukaryotic cells, pre-mRNA splicing is catalyzed by the spliceosome, a highly dynamic molecular machinery that undergoes dramatic conformational and compositional rearrangements throughout the splicing cycle. These crucial rearrangements are largely driven by eight DExD/H-box RNA helicases. Interestingly, the four helicases participating in the late stages of splicing are all DEAH-box helicases that share structural similarities. This review aims to provide an overview of the structure and function of these DEAH-box helicases, including new information provided by recent cryo-electron microscopy structures of the spliceosomal complexes.

16.
Life Sci ; : 118797, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33285162

RESUMO

AIMS: Lung cancer was the most fatal malignancy, dominated the cancer related mortality list for years, and we tried to distinguish the lung adenocarcinoma patients at higher risk from those bearing lower therapy resistance and recurrence risk. MATERIALS: Patients information from clinical Sequencing Cohorts and from the Regional Medical Center of the Middle-West China were included. The whole-exome sequencing was analyzed for risk evaluation. KEY FINDINGS: We found that Smoking stimulated the oncogenic genes mutations, and the most frequently mutated genes of EGFR, KRAS, and TP53 (E/K/P) were identified. Different N stage affected the survival prognosis of patients bearing E/K/P mutations, but the T stage and AJCC stage did not. Radiation failed to prolong survival of phase II/III patients who didn't receive surgery. In those received surgery, radiation also failed to prolong survival of phase II/III patients. Radiation did not improve the prognosis in patients bearing E/K/P mutation burdens, whose differences were identified in gender or smoking-history classified groups. SIGNIFICANCE: Smoking status and history contributed to oncogenic mutation burdens associated therapy resistance, and the aggressive treatment, especially to radiation, may lead to worse therapy response to current and past smoking behavior.

17.
Medicine (Baltimore) ; 99(49): e23385, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33285724

RESUMO

BACKGROUND: Sepsis has become a global healthcare problem and continues to be one of the leading causes of death due to infection. In essence, early recognition and diagnosis of sepsis is needed to inhibit the transition into septic shock, which is correlated with higher mortality. Many studies have suggested antimicrobial de-escalation as one of the strategies to replace the empirical broad-spectrum antimicrobial treatment using a narrower antimicrobial therapy, especially among patients with sepsis. However, antimicrobial de-escalation therapeutic effects in sepsis remains unclear. We therefore performed the present study in an attempt to assess efficacy and safety of antimicrobial de-escalation therapy in patients with sepsis. METHODS: We will carry out a systematic literature search to establish the potentially eligible trials from electronic databases, including EMBASE (1980 to October 16, 2020), MEDLINE via PubMed (1966 to October 16, 2020), Web of Science (1965 to October 16, 2020), Cochrane Library (CENTRAL; 2020, Issue 10), WanFang databases (last searched October 16, 2020), and China National Knowledge Infrastructure (CNKI; last searched October 16, 2020). For this study, the language restrictions are English or Chinese. Two authors independently examined quality based on the Cochrane Risk of Bias Tool V.2.0 and extracted data. Data obtained from the study will be synthesised using applicable statistical methods. RESULTS: The results of the present study will systematically assess efficacy and safety of antimicrobial de-escalation therapy among patients with sepsis. CONCLUSION: The results of the present study will help to establish the efficacy and safety of antimicrobial de-escalation to treat patients with sepsis. It can also help to identify the most efficient and safe therapeutically-relevant method. ETHICS AND DISSEMINATION: The present study is a meta-analysis and the pooled results are based on published evidence. Therefore, ethics approval is not necessary. OSF REGISTRATION NUMBER: October 22, 2020.osf.io/93wym. (https://osf.io/93wym/).

18.
J Control Release ; 329: 121-135, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33279604

RESUMO

Calcium supplement is the most commonly adopted treatment for osteoporosis but usually requires high dose and frequency. The modality of calcium supplement is therefore overlooked by current nanomedicine-based osteoporosis therapies without proper oral formulations. Herein, we proposed a tetracycline (Tc) modified and monostearin (MS) coated amorphous calcium carbonate (ACC) platform (TMA) as oral bone targeted and osteoporosis microenvironment (water/pH) responsive carrier for in situ calcium supplement. Moreover, current osteoporosis therapies also fall short of finding suitable molecular target and effective therapeutic regimen to further increase the therapeutic efficacy over available treatment means. As a result, the simvastatin (Sim) was loaded into TMA to construct drug delivery system (TMA/Sim) capable of synergistically activating the bone morphogenetic proteins (BMPs)-Smad pathway to provide a novel therapeutic regimen for osteoblast promotion mediated osteoporosis therapy. Our results revealed that optimized TMA showed high accessibility and oral availability with targeted drug delivery to bone tissue. Most importantly, benefit from the effective in situ calcium supplement and targeted Sim delivery, this therapeutic regime (TMA/Sim) achieved better synergetic effects than conventional combination strategies with promising osteoporosis reversion performance under low calcium dosage (1/10 of commercial calcium carbonate tablet) and significantly attenuated side effects.

19.
Artigo em Inglês | MEDLINE | ID: mdl-33288718

RESUMO

No other environment hosts as many microbial cells as the marine sedimentary biosphere. While the majority of these cells are expected to be alive, they are speculated to be persisting in a state of maintenance without net growth due to extreme starvation. Here, we report evidence for in situ growth of anaerobic ammonium-oxidizing (anammox) bacteria in ∼80,000-y-old subsurface sediments from the Arctic Mid-Ocean Ridge. The growth is confined to the nitrate-ammonium transition zone (NATZ), a widespread geochemical transition zone where most of the upward ammonium flux from deep anoxic sediments is being consumed. In this zone the anammox bacteria abundances, assessed by quantification of marker genes, consistently displayed a four order of magnitude increase relative to adjacent layers in four cores. This subsurface cell increase coincides with a markedly higher power supply driven mainly by intensified anammox reaction rates, thereby providing a quantitative link between microbial proliferation and energy availability. The reconstructed draft genome of the dominant anammox bacterium showed an index of replication (iRep) of 1.32, suggesting that 32% of this population was actively replicating. The genome belongs to a Scalindua species which we name Candidatus Scalindua sediminis, so far exclusively found in marine sediments. It has the capacity to utilize urea and cyanate and a mixotrophic lifestyle. Our results demonstrate that specific microbial groups are not only able to survive unfavorable conditions over geological timescales, but can proliferate in situ when encountering ideal conditions with significant consequences for biogeochemical nitrogen cycling.

20.
Food Funct ; 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33289736

RESUMO

Isoleucine (Ile), as a branched-chain amino acid (BCAA), has a vital role in regulating body weight and muscle protein synthesis. However, the regulatory effect of Ile on muscle mass under high-fat diet (HFD) conditions and intramyocellular lipid deposition remains largely unclear. In this study, a feeding experiment with HFD with or without 25 g L-1 Ile was performed using 32 wild male C57BL/6J mice randomly divided into two groups. The results showed that Ile significantly increased both muscle and fat mass, as well as causing insulin resistance and meanwhile upregulating the levels of key adipogenic and myogenic proteins. More importantly, Ile damaged the mitochondrial function by vacuolation, swelling and cristae fracture in the gastrocnemius (GAS) and tibialis anterior (TA) with downregulation of mitochondrial function-related genes. Furthermore, Ile promoted myogenesis and more lipid droplet accumulation in myotubes. Compared with the control, the protein levels of myosin heavy chain (MyHC), myoblast determination protein 1 (MyoD), myogenin (MyoG), peroxisome proliferator-activated receptor gamma (PPARg) and fatty acid synthase (FAS) were upregulated in the Ile group, whereas the protein levels of adipose triglyceride lipase (ATGL) and lipoprotein lipase (LPL) were downregulated. Collectively, Ile increased muscle mass through myogenesis and intramyocellular lipid deposition. Our findings provide a new perspective for not only improving the lean juiciness of farm animals by increasing intramyocellular lipid accumulation, but also modulating myopathies under obesity.

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