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2.
Zhongguo Zhen Jiu ; 41(7): 747-50, 2021 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-34259406

RESUMO

OBJECTIVE: To observe the effect of acupoint thread-embedding on visual acuity and morphology of retina in children with refractive amblyopia. METHODS: A total of 60 children with refractive amblyopia were randomized into an observation group (30 cases, 2 cases dropped off) and a control group (30 cases, 1 case dropped off). In the control group, comprehensive therapy of eye covering of intact side and family refined performance was adopted. On the basis of the treatment in the control group, acupoint thread-embedding was applied at Ganshu (BL 18), Pishu (BL 20), Shenshu (BL 23), Zusanli (ST 36), Guangming (GB 37) in the observation group, once every 2 weeks. The treatment for 2 months was required in the both groups. The corrected vision and the variations of macular thickness of retina and average thickness of retinal nerve fiber layer (RNFL) before and after treatment were observed, and the therapeutic efficacy was evaluated in the both groups. RESULTS: After treatment, the corrected vision was increased compared before treatment in the both groups (P<0.05), and the improvement of corrected vision in the observation group was superior to that in the control group (P<0.05); the macular thickness of retina and the average thickness of RNFL were thinner compared before treatment in the both groups (P<0.05), and the macular thickness of retina and the average thickness of RNFL in the observation group were thinner than those in the control group (P<0.05). The total effective rate was 92.9% (26/28) in the observation group, which was superior to 79.3% (23/29) in the control group (P<0.05). CONCLUSION: Acupoint thread-embedding can effectively increase the corrected vision in children with refractive amblyopia, and has improvement in retina morphological damage to a certain extent.

3.
Ann Fam Med ; 19(4): 332-341, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34264834

RESUMO

PURPOSE: Although the cost and complexity of managing diabetes is increasing around the world, placing greater burden on patients and their families, the cost of drug regimens prescribed to Chinese patients has not been evaluated. This study was conducted to evaluate the temporal changes in the costs and drugs used for people with diabetes. METHODS: Patients enrolled in Beijing Medical Insurance with outpatient medical records from 2016 through 2018 were included in this study. The outcomes of interest were: (1) the number of outpatient medications, (2) the number of comorbidities diagnosed, (3) the estimated annual cost of the outpatient drug regimen, (4) the drug therapy strategies used for diabetic patients, and (5) the most commonly prescribed classes of drugs. RESULTS: Over the 3-year period, there was a significant decrease (9.0%, P <.001) in the average number of diabetes medications used. Both antiglycemic and non-antiglycemic drug use decreased by 3.6% and 12.9%, respectively. Similarly, for estimated annual costs of medication, an 18.4% (P <.05) decrease was observed, with a gradual decreased from ¥6,868 ($1,059) in 2016 to ¥5,605 ($865) in 2018. CONCLUSION: This is the first large-scale cost analysis of the medical management of diabetes since the implementation of medical insurance in China. Despite the increasing availability of newer, more expensive diabetes drugs, there was a significant reduction in the number of diabetes medications used, that may be due to a more rational approach to optimizing metabolic targets.

4.
Acta Pharmacol Sin ; 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253877

RESUMO

Vacuolar protein sorting 33B (VPS33B) is important for intracellular vesicular trafficking process and protein interactions, which is closely associated with the arthrogryposis, renal dysfunction, and cholestasis syndrome. Our previous study has shown a crucial role of Vps33b in regulating metabolisms of bile acids and lipids in hepatic Vps33b deficiency mice with normal chow, but it remains unknown whether VPS33B could contribute to cholestatic liver injury. In this study we investigated the effects of hepatic Vps33b deficiency on bile acid metabolism and liver function in intrahepatic cholestatic mice. Cholestasis was induced in Vps33b hepatic knockout and wild-type male mice by feeding 1% CA chow diet for 5 consecutive days. We showed that compared with the wild-type mice, hepatic Vps33b deficiency greatly exacerbated CA-induced cholestatic liver injury as shown in markedly increased serum ALT, AST, and ALP activities, serum levels of total bilirubin, and total bile acid, as well as severe hepatocytes necrosis and inflammatory infiltration. Target metabolomics analysis revealed that hepatic Vps33b deficiency caused abnormal profiles of bile acids in cholestasis mice, evidenced by the upregulation of conjugated bile acids in serum, liver, and bile. We further demonstrated that the metabolomics alternation was accompanied by gene expression changes in bile acid metabolizing enzymes and transporters including Cyp3a11, Ugt1a1, Ntcp, Oatp1b1, Bsep, and Mrp2. Overall, these results suggest a crucial role of hepatic Vps33b deficiency in exacerbating cholestasis and liver injury, which is associated with the altered metabolism of bile acids.

5.
Synapse ; 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34255372

RESUMO

Our prior studies demonstrated that the rat hippocampal opioid system can undergo sex-specific adaptations to external stimuli that can influence opioid-associated learning processes. This opioid system extensively overlaps with the cannabinoid system. Moreover, acute administration of Δ9 Tetrahydrocannabinoid (THC), the primary psychoactive constituent of cannabis, can alter cognitive behaviors that involve the hippocampus. Here we use light and electron microscopic immunocytochemical methods to examine the effects of acute THC (5 mg/kg, i.p. 1 hour) on mossy fiber Leu-Enkephalin (LEnk) levels and the distribution and phosphorylation levels of delta and mu opioid receptors (DORs and MORs, respectively) in CA3 pyramidal cells and parvalbumin dentate hilar interneurons of adult female and male Sprague-Dawley rats. In females with elevated estrogen states (proestrus/estrus stage), acute THC altered the opioid system so that it resembled that seen in vehicle-injected females with low estrogen states (diestrus) and males: 1) mossy fiber LEnk levels in CA2/3a decreased; 2) phosphorylated-DOR levels in CA2/3a pyramidal cells increased; and 3) phosphorylated-MOR levels increased in most CA3b laminae. In males, acute THC resulted in the internalization of MORs in parvalbumin-containing interneuron dendrites which would decrease disinhibition of granule cells. In both sexes, acute THC redistributed DORs to the near plasma membrane of CA3 pyramidal cell dendrites, however, the dendritic region varied with sex. Additionally, acute THC also resulted in a sex-specific redistribution of DORs within CA3 pyramidal cell dendrites which could differentially promote synaptic plasticity and/or opioid-associated learning processes in both females and males. This article is protected by copyright. All rights reserved.

6.
Chem Asian J ; 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34255429

RESUMO

Electrocatalysts play a pivotal role in accelerating the sluggish electrochemical water splitting reaction. Herein, a Ru-Co oxides and carbon nitrides hybrid (RuCoO x /NC) electrocatalyst was constructed by employing ZIF-9 to disperse Ru precursor and deliberately regulating the calcination temperature. The moderate calcination temperature results in the RuCoO x nanocomposites with small particle size and low crystallinity as well as the co-existence of multi-valence metal compounds, thus boosting the amount and variety of active sites. Moreover, the strong interactions between Co and Ru species induce the electron transfer from Co to Ru, thus enhancing the adsorption of anion intermediates on the electron-deficient Co species and the proton capturing capacity of electron-sufficient Ru species. As a result, the optimized RuCoO x /NC-350 behaved good electrocatalytic activities with 73 and 210 mV overpotential to achieve 10 mA cm -2 for HER and OER, respectively. Remarkably, it showed good durability by holding at 100 mA cm -2 for 100 h in HER and 50 mA cm -2 for 24 h in OER with small activity decline. This study may shed new light on the rational construction of highly efficient Ru-based catalysts for the application of water splitting.

7.
Int J Biol Macromol ; 186: 385-395, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34197855

RESUMO

The structures and immunomodulatory activities of two polysaccharides (SDH-WA and SDH-0.2A) from Rehmanniae Radix Praeparata (RRP) were investigated. RRP crude polysaccharide was obtained by water extraction and purified. Ion chromatography, high-performance gel permeation chromatography, Fourier-transform infrared spectroscopy, methylation analysis, gas chromatography-mass spectrometry, and nuclear magnetic resonance were used to characterize the polysaccharides. The main chain of SDH-WA was →6)-α-D-Galp-(1→6)-α-D-Galp-(1→5)-α-L-Araf-(1→3,5)-α-L-Araf-(1→, terminal sugar residue α-L-Araf-(1→ linked to residue →3,5)-α-L-Araf-(1→ on the main chain by an O-3 bond. The other two terminal sugar residues α-D-Galp-(1→ and →6)-ß-D-Galp were linked to the end of the main chain. The main chain of SDH-0.2A was →2,4)-α-L-Rhap-(1→4)-α-D-GalpA-(1→. Three branched chains α-D-Galp-(1→6)-α-D-Galp-(1→5)-α-L-Araf-(1→3,5)-α-L-Araf-(1→, →3,6)-ß-D-Galp-(1→5)-α-L-Araf-(1→, and →4)-ß-D-Galp-(1→5)-α-L-Araf-(1→ were linked to the main chain residue →2,4)-α-L-Rhap-(1→ by an O-2 bond. Three terminal sugar residues α-D-Galp-(1→, α-L-Araf-(1→, and →6)-ß-D-Galp were linked to the end of the chain. Both polysaccharides showed no cytotoxic effects on and significantly promoted the phagocytic activity of RAW264.7 cells. They dose-dependently improved lysozyme activity and stimulated the production of TNF-α and IL-6 by RAW264.7 cells, but attenuated the secretion of lysozymes, TNF-α, IL-6, IL-1ß, and nitric oxide by lipopolysaccharide-induced RAW264.7 cells. The present studies suggest that PRR polysaccharide is a valuable source with immunomodulating.

8.
J Magn Reson Imaging ; 2021 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-34278649

RESUMO

BACKGROUND: Several magnetic resonance imaging (MRI) sequences have been applied to assess injured glands but without histological validation. PURPOSE: To evaluate longitudinal changes in multiparametric MRI (mp-MRI) of irradiated salivary glands in a rat model and investigate correlations between mp-MRI and histological findings. STUDY TYPE: Prospective. ANIMAL MODEL: Submandibular glands of 36 rats were radiated using a single dose of 15 Gy X-ray (irradiation [IR] group), and 6 other rats were enrolled into sham-IR group. mp-MRI were scanned 1 day after sham-IR (n = 6), or 1, 2, 4, 8, 12, 24 weeks after IR (n = 36, 6 per subgroup). FIELD STRENGTH/SEQUENCE: A 3.0-T/Diffusion-weighted imaging (DWI), readout-segmented echo-planar imaging (EPI) sequence; intravoxel incoherent motion DWI, single-shot EPI sequence; T1 mapping, dual-flip-angle gradient-echo sequence with volumetric interpolated breath-hold examination; T2 mapping, turbo spin-echo sequence. ASSESSMENT: Parameters including apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D* ), perfusion fraction (f), T1 and T2 value were obtained. Histological examinations, including hematoxylin and eosin staining (for acinar cell fraction [AC%] detection), Masson's trichrome staining (for degree of fibrosis [F%] determination) and CD34-immunohistochemical staining (for microvessel density [MVD] calculation), were performed at corresponding time points. STATISTICAL TESTS: One-way analysis of variance was used to compare the mp-MRI and histological parameters among different groups. Spearman correlation analysis was applied to determine the correlation between mp-MRI and histological parameters. Two-sided P ≤ 0.05 was considered statistically significant. RESULTS: Changes of mp-MRI parameters (ADC, D, D* , f, T1, T2) and histological results (AC%, F%, MVD) among the seven groups were all significant. ADC, D, and T2 values negatively correlated with AC% (ADC, r = -0.728; D, r = -0.773; T2, r = -0.600), f positively correlated with MVD (r = 0.496), and T1 values positively correlated with F% (r = 0.714). DATA CONCLUSION: mp-MRI might be able to noninvasively and quantitatively evaluate the dynamic pathological changes within the irradiated salivary glands. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.

9.
Artigo em Inglês | MEDLINE | ID: mdl-34279752

RESUMO

OBJECTIVES: We sought to distinguish area at risk from salvage myocardial zone and to predict left ventricle functional recovery in the convalescent stage by Texture Analysis (TA) of T2-Mapping. METHODS: One hundred and six patients diagnosed with AMI and treated with percutaneous coronary intervention (PCI) underwent acute cardiac magnetic resonance imaging (CMR) and 45 of whom had a subsequent CMR scan following recovery. Cine imaging, T2-Mapping, T2-weighted STIR imaging, and LGE imaging were performed. In the texture analysis, regions of interest (infarcted, salvageable, and remote) were drawn by two blinded, independent readers. RESULTS: Seven independent texture features on T2-Mapping were selected: Perc.50%, S(2,2)InvDfMom, S(2.-2)AngScMom, S(4,0)Entropy, 45dgrLngREmph, 45dgr_Fraction and 135dr_GLevNonU. Among them, the average value of 135dr_GLevNonU in the infarct zone, AAR zone, and the remote zone was: 61.96±26.03, 31.811±18.933 and 99.839±26.231, respectively. Additionally, 135dr_GLevNonU provided the highest area under the curve (AUC) from the receiver operating characteristic curve (ROC curve) for distinguishing AAR from the infarct zone in each subgroup (all patients, patients with MVO and)were 0.845 ± 0.052 0.855 ± 0.083 and 0.845 ± 0.066, respectively, and were more promise than T2-Mapping mean (p<0.001). The AUC for differentiating AAR from the remote zone is 0.942±0.041. Texture features are not associated with convalescent decreased strain, ejection fraction (EF) or left ventricle remodeling (LVR) in analysis (p>0.05). CONCLUSION: TA of T2-mapping can distinguish AAR from both the infarct zone and the remote myocardial zone without LGE imaging in reperfused AMI. However, these features are not able to predict patients' functional recovery in the convalescent stage.

10.
Chin Med J (Engl) ; 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34267067

RESUMO

BACKGROUND: Geriatric hip fracture patients receiving clopidogrel are a surgical challenge. In China, most of these patients undergo delayed surgical treatment after clopidogrel withdrawal for at least 5 to 7 days. However, delayed surgery is associated with increased complications and mortality in the older adults. This retrospective paralleled comparison study investigated the safety of early surgery for geriatric hip fracture patients within 5 days of clopidogrel withdrawal. METHODS: Acute hip fracture patients (≥65 years) who were hospitalized in the orthogeriatric co-management ward of Beijing Jishuitan Hospital between November 2016 and April 2018 were retrospectively reviewed. Sixty patients taking clopidogrel before injury and discontinued <5 days before surgery constituted the clopidogrel group. The control group constituted 60 patients not taking antiplatelet or anticoagulant drugs and matched 1:1 with the clopidogrel group for sex, fracture type, operative procedure, and time from injury to operation (±10 h). The primary outcome was perioperative blood loss and the secondary outcomes were transfusion requirement, complications, and mortality. The Student's t test or Wilcoxon signed rank sum test was used for continuous variables and the Chi-square test was used for categorical variables. RESULTS: Age, body mass index, American Society of Anesthesiologists score, and percentage undergoing general anesthesia were comparable between the groups (P > 0.050). The percentages of patients with coronary heart disease (61.7% vs. 18.3%; P < 0.001) and cerebrovascular disease (45.0% vs. 15.0%; P < 0.010) were significantly higher in the clopidogrel vs. control groups, respectively. The median clopidogrel discontinuation time before operation was 73.0 (range: 3.0-120.0) h. There was no significant difference in the estimated perioperative blood loss between the clopidogrel group (median: 745 mL) and control group (median: 772 mL) (P = 0.866). The intra-operative transfusion rate was higher in the clopidogrel group (22/60, 36.7%) than that in the control group (12/60, 20.0%) (P < 0.050). However, there was no significant difference in the blood transfusion rate during the entire perioperative period (26/60, 43.3% vs. 20/60, 33.3%; clopidogrel group vs. control group, respectively; P > 0.050). There was no significant difference in perioperative complications, and 30-day and 1-year mortality rates between the groups. CONCLUSIONS: Early hip fracture surgery is safe for elderly patients within 5 days of clopidogrel withdrawal, without increased perioperative blood loss, transfusion requirement, complications, and mortality compared with patients not taking antiplatelet drugs.

11.
Eur J Med Res ; 26(1): 73, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34247652

RESUMO

BACKGROUND: Shoulder dislocation and the cases of iatrogenic fractures during manual reduction are becoming increasingly common. The aim of this study was to investigate the characteristics, management, and patient outcomes of iatrogenic proximal humeral fracture during the manual reduction of shoulder dislocation. METHODS: A retrospective and multi-center study was performed to identify all patients presenting with shoulder dislocation from January 2010 to January 2020. The sex and age of patients, associated injuries, first-time or habitual shoulder dislocation, type of anesthesia, time from injury to revision surgery, and functional outcomes were analyzed. RESULTS: A total of 359 patients with a mean age of 62.1 ± 7.3 years (range 29-86 years) were included. Twenty-one patients (female/male ratio 17:4) with an average age of 66.3 ± 9.7 years (range 48-86 years) were identified with a post-reduction iatrogenic fracture. Female cases with greater tuberosity fractures (GTF) were more likely than male cases to have iatrogenic fractures during reduction (P = 0.035). Women aged 60 years or older experienced more iatrogenic fractures during manual reduction (P = 0.026). Closed reduction under conscious sedation was more likely than that under general anesthesia to have iatrogenic fractures (P = 0.000). A total of 21 patients underwent open reduction and internal fixation (ORIF) when iatrogenic fractures occurred. The mean follow-up period was 19.7 ± 6.7 months (range 12-36 months). The mean Neer scores were 80.5 ± 7.6 (range 62-93), and the mean visual analog score (VAS) was 3.3 ± 1.5 (range 1-6). Significant differences were observed in the Neer score and VAS with the time (more or less 8 h) from injury to revision surgery (P < 0.05). CONCLUSION: A high risk of iatrogenic proximal humeral fracture is present in shoulder dislocation with GTF in senile females without general anesthesia. ORIF performed in a timely manner may help improve functional outcomes in the case of iatrogenic injury.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34229301

RESUMO

Magnetic skyrmions are potential building blocks for future information storage and computing devices. Here, we computationally study the skyrmion dynamics in a cross structure made of two ferromagnetic nanotracks. We show that by controlling the skyrmion motion in the cross structure using spin currents, it is possible to realize the transcription of skyrmion at the intersection of the cross structure at certain conditions. Based on the transcription of skyrmion, we computationally demonstrate the AND, OR and NOT logical gates using the cross structures with modified geometries and appropriate magnetic parameters. Our results may provide guidelines to design future three-dimensional spintronics devices based on magnetic skyrmions.

13.
Neurosci Lett ; 760: 136092, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34197905

RESUMO

Though it is well known that G protein-coupled receptor kinase 2 [GRK2] is involved in regulation of mu opioid receptor [MOR] desensitization and morphine-related behaviors, the potential role of GRK2 in regulation of kappa opioid receptor [KOR] functions in vivo has not been established yet. A couple of recent studies have found that GRK2 activity desensitizes KOR functions via decreasing G protein-coupled signaling with sensitizing arrestin-coupled signaling. Nalfurafine, a G protein-biased KOR full agonist, produces an inhibitory effect on alcohol intake in mice, with fewer side effects (sedation, aversion, or anxiety/depression-like behaviors). Using RNA sequencing (RNA-seq) analysis, we first identified that nuclear transcript level of grk2 [adrbk1] (but not other grks) was significantly up-regulated in mouse nucleus accumbens shell (NAcs) after chronic excessive alcohol drinking, suggesting alcohol specifically increased NAcs grk2 expression. We then tested whether selective GRK2/3 inhibitor CMPD101 could alter alcohol intake and found that CMPD101 alone had no effect on alcohol drinking. Therefore, we hypothesized that the grk2 increase in the NAcs could modulate the nalfurafine effect on alcohol intake via interacting with the G protein-mediated KOR signaling. Nalfurafine decreased alcohol drinking in a dose-related manner, and pretreatment with CMPD101 enhanced the reduction in alcohol intake induced by nalfurafine, indicating an involvement of GRK2/3 blockade in modulating G protein-biased KOR agonism of nalfurafine. Together, our study provides initial evidence relevant to the transcriptional change of grk2 gene in the NAc shell after excessive alcohol drinking. Pharmacological GRK2/3 blockade enhanced nalfurafine's efficacy, suggesting a GRK2/3-mediated mechanism, probably through the G protein-mediated KOR signaling.

14.
PLoS Pathog ; 17(7): e1009751, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34252150

RESUMO

Our knowledge of citrus viruses is largely skewed toward virus pathology in cultivated orchards. Little is known about the virus diversity in wild citrus species. Here, we used a metatranscriptomics approach to characterize the virus diversity in a wild citrus habitat within the proposed center of the origin of citrus plants. We discovered a total of 44 virus isolates that could be classified into species Citrus tristeza virus and putative species citrus associated ampelovirus 1, citrus associated ampelovirus 2, and citrus virus B within the family Closteroviridae, providing important information to explore the factors facilitating outbreaks of citrus viruses and the evolutionary history of the family Closteroviridae. We found that frequent horizontal gene transfer, gene duplication, and alteration of expression strategy have shaped the genome complexity and diversification of the family Closteroviridae. Recombination frequently occurred among distinct Closteroviridae members, thereby facilitating the evolution of Closteroviridae. Given the potential emergence of similar wild-citrus-originated novel viruses as pathogens, the need for surveillance of their pathogenic and epidemiological characteristics is of utmost priority for global citrus production.

15.
Mol Med Rep ; 24(3)2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34212978

RESUMO

Fibrosis of lung tissue can induce the occurrence and development of numerous types of lung disease. The expression levels of the long non­coding RNA (lncRNA) HOXA distal transcript antisense RNA (HOTTIP) have been reported to be upregulated during the development of fibrosis in liver tissues, which subsequently activated hepatic stellate cells. However, whether the lncRNA HOTTIP participates in the occurrence and development of lung fibrosis remains unknown. The present study aimed to investigate the role of lncRNA HOTTIP in lung fibrosis and its potential mechanism. In the present study, A549 cells were stimulated with TGF­ß1 to induce lung fibrosis in vitro. A549 was transfected with short hairpin RNA­HOTTP, overexpression­polypyrimidine tract binding protein 1 (PTBP1), microRNA (miR)­744­5p mimic or miR­744­5p to regulate gene expression. Cell proliferation and migration were determined using 5'­ethynl­2'­deoxyuridine and wound healing assays, respectively. The expression levels of α­smooth muscle actin, collagen I, collagen III and fibronectin 1 were analyzed using western blotting. starBase was used to identify molecules that may interact with the lncRNA HOTTIP and dual luciferase reporter assays were used to validate the findings. Moreover, an in vivo lung fibrosis model was established by bleomycin induction in mice. Histological injury was observed using hematoxylin and eosin and masson staining. The results of the present study revealed that the proliferation and migration of A549 cells were both suppressed following the knockdown of HOTTIP. The lncRNA HOTTIP was found to target and downregulate the expression levels of miR­744­5p. The overexpression of miR­744­5p inhibited the proliferation and migration of A549 cells. Furthermore, miR­744­5p targeted and downregulated the expression levels of PTBP1. It was subsequently demonstrated that the overexpression of PTBP1 rescued miR­744­5p­induced suppression of the proliferation and migration of A549 cells. The knockdown of lncRNA HOTTIP expression also relieved the fibrosis of the lung tissues of mice. In conclusion, the results of the present study suggested that the lncRNA HOTTIP may promote the fibrosis of lung tissues by downregulating the expression levels of miR­744­5p and upregulating the expression levels of PTBP1.

16.
Parasitol Int ; 85: 102416, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34217794

RESUMO

This study aimed to identify species of Fasciola flukes in Dali Prefecture (Yunnan Province, China) and analyze their genetic diversity. Fasciola flukes (n = 122) were collected from cattle livers in a farmers' market in Xiaguan Town, Dali Prefecture. Nucleotide sequences of ribosomal internal transcribed spacer (ITS) as well as nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) and mitochondrial cytochrome c oxidase subunit 1 (CO1) were amplified, sequenced, and subjected to homology analysis. The heterozygosity ratios of different ITS alleles were determined using the peak-height ratio of heterozygous loci. Multiplex PCR analysis of the nuclear protein coding gene, phosphoenolpyruvate carboxykinase (pepck), was used to identify Fasciola species. Multiple ND1 sequence alignments enabled further genetic diversity analysis of regional Fasciola flukes. Seven ITS sequences belonged to F. hepatica and 115 belonged to Fh/Fg heterozygous flukes. Sequencing analysis of heterozygous flukes revealed 11 heterozygous loci with double peaks, with significantly variable ratios among individuals. ND1 and CO1 results indicated that one specimen was identical to F. hepatica, while 121 specimens were identical to F. gigantica or contained one variable site. Multiplex PCR results for pepck showed that double bands for F. hepatica and F. gigantica were amplified from Dali Fasciola specimens; hence, they were all heterozygous. By combining ITS, ND1, and CO1 sequences with multiplex pepck PCR results, all 122 specimens were identified as Fh/Fg heterozygous Fasciola flukes. Our experimental results preliminarily confirmed a high degree of Fh/Fg heterozygosity among Fasciola flukes in the Dali area. Selecting multiple molecular markers for concurrent analysis will provide more comprehensive and accurate genetic information.

17.
Water Res ; 202: 117373, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34243051

RESUMO

Biochemical oxidation and reduction are the principle of biological water and wastewater treatment, in which electron donor and/or acceptor shall be provided. Elemental sulfur (S0) as a non-toxic and easily available material with low price, possesses both reductive and oxidative characteristics, suggesting that it is a suitable material for water and wastewater treatment. Recent advanced understanding of S0-respiring microorganisms and their metabolism further stimulated the development of S0-based technologies. As such, S0-based biotechnologies have emerged as cost-effective and attractive alternatives to conventional biological methods for water and wastewater treatment. For instance, S0-driven autotrophic denitrification substantially lower the operational cost for nitrogen removal from water and wastewater, compared to the conventional process with exogenous carbon source supplementation. The introduction of S0 can also avoid secondary pollution commonly caused by overdose of organic carbon. S0 reduction processes cost-effectively mineralize organic matter with low sludge production. Biological sulfide production using S0 as electron acceptor is also an attractive technology for metal-laden wastewater treatment, e.g. acid mine drainage. This paper outlines an overview of the fundamentals, characteristics and advances of the S0-based biotechnologies and highlights the functional S0-related microorganisms. In particular, the mechanisms of microorganisms accessing insoluble S0 and feasibility to improve S0 bio-utilization efficiency are critically discussed. Additionally, the research knowledge gaps, current process limitations, and required further developments are identified and discussed.

18.
J Chem Theory Comput ; 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34283604

RESUMO

First-principles determination of free energy profiles for condensed-phase chemical reactions is hampered by the daunting costs associated with configurational sampling on ab initio quantum mechanical/molecular mechanical (AI/MM) potential energy surfaces. Here, we report a new method that enables efficient AI/MM free energy simulations through mean force fitting. In this method, a free energy path in collective variables (CVs) is first determined on an efficient reactive aiding potential. Based on the configurations sampled along the free energy path, correcting forces to reproduce the AI/MM forces on the CVs are determined through force matching. The AI/MM free energy profile is then predicted from simulations on the aiding potential in conjunction with the correcting forces. Such cycles of correction-prediction are repeated until convergence is established. As the instantaneous forces on the CVs sampled in equilibrium ensembles along the free energy path are fitted, this procedure faithfully restores the target free energy profile by reproducing the free energy mean forces. Due to its close connection with the reaction path-force matching (RP-FM) framework recently introduced by us, we designate the new method as RP-FM in collective variables (RP-FM-CV). We demonstrate the effectiveness of this method on a type-II solution-phase SN2 reaction, NH3 + CH3Cl (the Menshutkin reaction), simulated with an explicit water solvent. To obtain the AI/MM free energy profiles, we employed the semiempirical AM1/MM Hamiltonian as the base level for determining the string minimum free energy pathway, along which the free energy mean forces are fitted to various target AI/MM levels using the Hartree-Fock (HF) theory, density functional theory (DFT), and the second-order Møller-Plesset perturbation (MP2) theory as the AI method. The forces on the bond-breaking and bond-forming CVs at both the base and target levels are obtained by force transformation from Cartesian to redundant internal coordinates under the Wilson B-matrix formalism, where the linearized FM is facilitated by the use of spline functions. For the Menshutkin reaction tested, our FM treatment greatly reduces the deviations on the CV forces, originally in the range of 12-33 to ∼2 kcal/mol/Å. Comparisons with the experimental and benchmark AI/MM results, tests of the new method under a variety of simulation protocols, and analyses of the solute-solvent radial distribution functions suggest that RP-FM-CV can be used as an efficient, accurate, and robust method for simulating solution-phase chemical reactions.

20.
Anal Chem ; 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34284576

RESUMO

Minimally invasive techniques for in vivo tissue analysis are desired by life science and medical research. Herein, a new ionization interface coupled with ldesorption (USD) was developed for in vitro and in vivo tissue analysis. Sample molecules were effectively sputtered out when the high-frequency ultrasonic probe touched the tissue. Then, the sputtered molecules were collected and ionized by a custom-made heated quartz tube and finally analyzed by mass spectrometry (MS) online. The sample pretreatment of the USD-MS technique was quite simple and required no other steps except for wetting the tissue surface with ethanol to assist molecular extraction. Experimental results demonstrated that the proposed method was suitable for the analysis of different morphologies of tissues (such as liver, brain, kidney, and lung) and performed well in the analysis of liver tumors and paracancerous tissues. Moreover, as the proposed method caused little damage to the tissues during analysis, rats and mice with orthotopic tumors still survived after the experiments. Overall, the newly developed USD-MS technique was an effective tool for minimally invasive tissue analysis and could be used as a new candidate method for in situ and real-time analysis of biological tissues in vitro and in vivo.

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