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1.
Clin Exp Nephrol ; 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32172373

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is commonly associated with sleep disturbance. However, the relationship between the trajectory of sleep quality and short-term residual renal function is not clear. Thus, this study aimed to investigate such relationship. METHODS: In total, 132 patients with CKD stage 3-5 were prospectively enrolled. All participants were followed-up for 6 months. The Pittsburgh Sleep Quality Index (PSQI) questionnaire was used to assess sleep quality. The longitudinal PSQI and estimated glomerular filtration rate (eGFR) were measured at baseline, the 3rd month and 6th month. The participants were stratified into three groups according to the PSQI trajectories. The primary outcome was set as the eGFR change among 6 months less than the median. RESULTS: Sixty nine participants showed PSQI ≤ 5 at baseline and 15 patients had increased scores > 5 at 3rd month among them. 63 participants showed PSQI > 5 at baseline and 11 patients had decreased scores ≤ 5 at 3rd month. Only in patients whose baseline PSQI ≤ 5 but increased to > 5 at 3rd month presented a longitudinal decline in eGFR at both 3rd month and 6th month compared with baseline eGFR. Linear regression analysis for eGFR change showed no significant association between eGFR change and PSQI score. Logistic regression revealed worsen sleep quality will deteriorate renal function. CONCLUSION: A relationship was observed between worsening sleep quality and eGFR decline in non-dialysis CKD patients.

2.
Chemosphere ; 250: 126220, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32120146

RESUMO

In this study, an anoxic-oxic membrane bioreactor (A/O-MBR), was used to treat effluent tannery wastewater pretreated by physicochemical processes. The A/O-MBR performed well during the experimental period and was able to produce a high-quality effluent containing 90 ± 10 mg-CODcr/L and 0.5 ± 0.1 mg-NH4+-N/L. However, it was observed that at rates of approximately 1.02 kPa/day and 1.2 µm/day, both transmembrane pressure (TMP) and thickness of cake layer increased during wastewater treatment. The eventual thickness of the cake layer was between 47.8 and 51.5 µm. Furthermore, an Inductively Coupled Plasma-Optical Emission Spectrometer, used to analyze inorganic components of the cake layer, revealed that four inorganic elements, Cr, Ca, Mg and Al were predominant (weight percentage rate 4:13:10:72). Due to low solubility (Cr(OH)3: Ksp 6.3 × 10-31; Al(OH)3: Ksp 6.3 × 10-19), the elements of Cr and Al mainly existed in the forms of Cr(OH)3 and Al(OH)3, respectively. Other minerals in the cake layer included Al2O3, CaCO3, and MgCO3. Additionally, using an SEM-EDX (Scanning electron microscopy-energy dispersive X-ray analyzer), we discovered that inorganic particles that formed within the activated sludge of the A/O-MBR steadily accumulating on the membrane surface, resulted in an evenly distributed inorganic layer which could be observed along the cross-sections of the cake layer.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32124183

RESUMO

Peroxidation damage induces sublethal injury to boar sperm during preservation. Rosmarinic acid (RA) has already been verified to efficiently protect cells from oxidant-induced injury and to produce significant effect on cryopreservation of semen. Through our experiments, we aim at investigating whether RA has a positive effect on the preservation of pig semen at room temperature. The semen collected from sexually mature Large White boars were preserved at 17 °C in Beltsville thawing solution (BTS) supplied. The boar sperm were exposed to 0, 25, 50, 75, 100, 125 and 150 µM RA in vitro and the sperm functions were examined. The sperm motility, the acrosome and plasma membrane integrity, the catalase activity (CAT), the total antioxidative capacity (T-AOC) activity and the malondialdehyde content (MDA) were examined at 0, 1, 3 and 5 days. The BTS diluent containing RA improved the sperm quality during the process of liquid preservation compared with the control treatment. After 5 days of liquid preservation, the addition of RA at 100 µM produced an optimal effect on the survival time as well as on the maintenance of motility, acrosome and plasma membrane integrity; T-AOC activity; CAT activity; and the MDA content. Besides, our results in the reproductive experiments showed that the addition of RA at 100 µM to the BTS diluent increased the pregnancy rate. These results suggest that the proper concentration of RA in boar semen extenders possibly improves the artificial insemination efficiency by reducing the sperm damage and the subsequent dysfunction during liquid preservation in swine production systems.

4.
Int Urol Nephrol ; 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32124234

RESUMO

PURPOSE: Sleep disturbances have a negative impact on the prognosis of chronic kidney disease (CKD). However, information on the prevalence and predictors is limited. This study aimed to evaluate the prevalence and explore clinical factors affecting the quality of sleep in patients with non-dialysis CKD. METHODS: Participants included 152 adult non-dialysis patients with stage 3-5 CKD. Demographic and clinical data were collected. Sleep quality and depression were assessed using the Pittsburgh Sleep Quality Index (PSQI) and Beck Depression Inventory (BDI), respectively. Sleep disturbances were defined as a PSQI score ≥ 5. Logistic regression was conducted to explore the independent factors of sleep disturbances. Clinical parameters were correlated with BDI scores using linear regression models. RESULTS: The total prevalence of patients with sleep disturbances was 66.4%. Older age, higher BDI scores, lower estimated glomerular filtration rate (eGFR) changes per month (△eGFR/m) before the study, and lower serum magnesium levels were found in patients with sleep disturbances. BDI scores (odds ratio [OR] 1.224, 95% confidence interval [CI] 1.091-1.373, p = 0.001) and age (OR 1.041, 95% CI 1.013-1.069, p = 0.003) were independent predictors of sleep disturbances. Serum uric acid levels (ß - 0.629, 95% CI - 1.244 to - 0.013, p = 0.046), △eGFR/m before the study (ß - 0.454, 95% CI - 0.885 to - 0.024, p = 0.039), and daily protein intake (ß - 0.052, 95% CI - 0.102 to - 0.002, p = 0.043) were negatively associated with BDI scores. CONCLUSION: A high overall prevalence of sleep disturbances was found in patients with non-dialysis stage 3-5 CKD. Depression, as a manageable predictor, should be managed, especially in elderly patients.

5.
ACS Appl Mater Interfaces ; 12(4): 4540-4548, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31904210

RESUMO

The defect passivation of perovskite films is an efficacious way to further boost the power conversion efficiency (PCE) and long-term stability of perovskite solar cells (PSCs). In this work, ionic liquids (ILs) of 1-butyl-2,3-dimethylimidazolium chloride ([BMMIm]Cl) are used as a modification layer in perovskite films in carbon-based CsPbBr3 PSCs without a hole-transporting material (HTM) for passivating the surface defects. The preliminary results demonstrate that the [BMMIm]Cl modifier passivates the surface defects of the perovskite film and reduces the valence band of perovskite close to the work function of the carbon electrode, which causes a remarkably inhibited nonradiative and radiative charge recombination, improved energy-level matching, and decreased energy loss. After optimization, a champion efficiency of 9.92% with a Voc as high as 1.61 V is achieved for the [BMMIm]Cl tailored carbon-based CsPbBr3 PSC without HTM, which is improved by 61.3% in comparison with 6.15% for the control device. Furthermore, the encapsulation-free PSC presents good long-term stability after storage in an air atmosphere with 70% RH at 20 °C or 0% RH at 80 °C as well as under continuous illumination conditions for 30 days. The significantly improved PCE and stability in high humidity or temperature suggest that the perovskite passivation by ILs is an effective strategy for fabricating high-PCE and stable PSCs.

6.
J Phys Chem A ; 124(4): 721-730, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31917920

RESUMO

The reaction of ethyl propyl ether (EnPE) with OH radicals was studied using proton-transfer-reaction mass spectrum (PTR-MS), and the rate constant was measured at 298 K and atmospheric pressure using the relative rate method: kexp(OH+EnPE) = (1.13 ± 0.09) × 10-11 cm3 molecules-1 s-1. In addition, a parallel theoretical study was performed using the traditional transition state theory (TST) with a tunnelling effect correction in combination at M05-2X method with two basis sets, 6-311++G(d,p) and aug-cc-pVTZ. According to these calculations, H atom abstraction occurs more favorably from the methylene group adjacent to the -O- bond than from the other groups. The theoretical calculation of the total rate constant of the reaction of EnPE with OH radicals was consistent with the experimental values. The gas-phase products indicated that the major products observed were ethyl formate, ethyl propionate, propionic acid. Combined with the experimental and theoretical results, the possible reaction mechanisms were proposed and discussed. The atmospheric implications of the studied reaction are presented, and the lifetime of EnPE in the presence of OH radicals was evaluated to be approximately 1 day.

7.
ChemSusChem ; 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31971332

RESUMO

The preparation of high-quality perovskite films with low grain boundaries and defect states is a prerequisite for achieving high-efficiency perovskite solar cells (PSCs) with good environmental stability. An effective additive engineering strategy has been developed for simultaneous defect passivation and crystal growth of CsPbBr3 perovskite films by introducing 1,3,5-triazine-2,4,6-triamine (melamine) into the PbBr2 precursor solution. The resultant melamine-PbBr2 film has a loose, large-grained structure and decreased crystallinity, which has a positive effect on the crystallization process of the perovskite as it retards the crystallization rate as a result of the interaction between melamine and lead ions. Additionally, the passivation by melamine gives a high-quality CsPbBr3 perovskite film with fewer grain boundaries, lower defect densities, and better energy level matching is achieved by multistep liquid-phase spin-coating, which greatly suppresses the nonradiative recombination resulting from the defects and promotes charge extraction at the interface. A champion power conversion efficiency as high as 9.65 % with a promising open-circuit voltage of 1.584 V is achieved for PSCs with an architecture of fluorine-doped tin oxide/c-TiO2 /m-TiO2 /melamine-added CsPbBr3 /carbon-based hole-transporting layer. Furthermore, the unencapsulated melamine-added CsPbBr3 PSC shows superior thermal and humidity stability in ambient air at 85 °C or 85 % relative humidity over 720 h.

8.
Bioresour Technol ; 297: 122450, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31796377

RESUMO

To investigate the methanogenic pathway and microbial community in a mesophilic anaerobic digestion (AD) system with food waste (FW) ethanol pre-fermentation (EP), two semi-continuous AD systems were operated by feeding FW with (PSR) and without EP (control). In this study, δ13C-ethanol was supplemented as solo substrate for AD sludge when the reactors operation stabilized to analyze the methanogenic pathways. The results suggested that approximately 59.3% of methane was produced from acetotrophic methanogens, while 40.7% was formed by hydrogenotrophic methanogens in the PSR group. On the other hand, compared with control, methane produced via CO2 reduction pathway was increased by 4.70%. Meanwhile, the composition variations of the microbial community in AD supported the above conclusion, since the relative abundances of Clostridium and Methanobacterium were enhanced by 7.6% and 10.2%, respectively in PSR reactor. These results provided a theoretical basis for AD applications and biogas yield improvements with EP process.


Assuntos
Microbiota , Eliminação de Resíduos , Anaerobiose , Reatores Biológicos , Etanol , Fermentação , Alimentos , Metano , Esgotos
9.
Cell Death Differ ; 27(2): 482-496, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31209362

RESUMO

Both the stress-response protein, SIRT1, and the cell cycle checkpoint kinase, CHK2, play critical roles in aging and cancer via the modulation of cellular homeostasis and the maintenance of genomic integrity. However, the underlying mechanism linking the two pathways remains elusive. Here, we show that SIRT1 functions as a modifier of CHK2 in cell cycle control. Specifically, SIRT1 interacts with CHK2 and deacetylates it at lysine 520 residue, which suppresses CHK2 phosphorylation, dimerization, and thus activation. SIRT1 depletion induces CHK2 hyperactivation-mediated cell cycle arrest and subsequent cell death. In vivo, genetic deletion of Chk2 rescues the neonatal lethality of Sirt1-/- mice, consistent with the role of SIRT1 in preventing CHK2 hyperactivation. Together, these results suggest that CHK2 mediates the function of SIRT1 in cell cycle progression, and may provide new insights into modulating cellular homeostasis and maintaining genomic integrity in the prevention of aging and cancer.

10.
Int J Cancer ; 146(4): 1139-1151, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31219614

RESUMO

Although clinically associated with the progression of multiple cancers, the biological function of p21-activated kinase 5 (PAK5) in breast cancer remains largely unknown. Here, we reveal that the PAK5-aspartyl aminopeptidase (DNPEP)-ubiquitin-specific protease 4 (USP4) axis is involved in breast cancer progression. We show that PAK5 interacts with and phosphorylates DNPEP at serine 119. Functionally, we demonstrate that DNPEP overexpression suppresses breast cancer cell proliferation and invasion and restricts breast cancer growth and metastasis in mice. Furthermore, we identify USP4 as a downstream target of the PAK5-DNPEP pathway; DNPEP mediates USP4 downregulation. Importantly, we verify that DNPEP expression is frequently downregulated in breast cancer tissues and is negatively correlated with PAK5 and USP4 expression. PAK5 decreases DNPEP abundance via the ubiquitin-proteasome pathway. Consistently, analyses of clinical breast cancer specimens revealed significantly increased PAK5 and USP4 levels and an association between higher PAK5 and USP4 expression and worse breast cancer patient survival. These findings suggest a pivotal role for PAK5-elicited signaling in breast cancer progression.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Glutamil Aminopeptidase/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Processos de Crescimento Celular/fisiologia , Feminino , Células HEK293 , Xenoenxertos , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Metástase Neoplásica , Fosforilação , Transdução de Sinais
11.
J Hazard Mater ; 382: 121081, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470296

RESUMO

Herein, a new peroxymonosulfate (PMS) activation system was proposed employing nonredox metal ions as Lewis acids (LA), which have been widely recognized to play important roles in many biological and chemical oxidations. With Co2+ ions as model catalysts, it was found that oxidizing power of PMS was enhanced after binding weak LA such as Ca2+ ions, leading to its easier reduction to active radicals and substantial enhancement of dye degradation. The promoting effect of Ca2+ was also observed with other cobalt catalysts including CoFe2O4 and Co3O4. The rate of PMS decomposition in Co2++LA/PMS system was correlated with Lewis acidity; while in the presence of strong LA including La3+ and Y3+, the dye degradation rate declined. The interactions of LA with PMS were characterized and the detailed mechanism was proposed. The present study provides the first example of the promoting effect of weak LA on PMS activation with cobalt based catalysts.

12.
Chemosphere ; 239: 124763, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31526989

RESUMO

Nonredox metal ions have been widely recognized to be important in a wide range of biological and chemical oxidations as Lewis acids (LA). However, the role of LA in peroxymonosulfate (PMS) activation for wastewater treatment has not been considered until now. This study shows that oxidizing power of PMS can be promoted after binding nonredox metal ions such as Ca2+ as LA, leading to the easier reduction of the oxidant to radicals and substantial enhancement of dye degradation by employing manganese oxides OMS-2 as model catalysts. Increased with Lewis acidity of the metal ion, the rate of PMS decomposition enhanced linearly, while the dye degradation rate first increased and then declined due to the formation of a larger amount of dioxygen. The interactions between Ca2+ and PMS were further investigated by Raman, cyclic voltammetry and XPS; and the detailed mechanism of PMS activation was proposed. The performance of Ca2++OMS-2/PMS system under different conditions was also studied. The findings indicate the importance of LA in PMS activation reaction and their role must be considered in other transition metal oxides/PMS systems. It will be also helpful to design new and highly active catalysts for the reactions.


Assuntos
Ácidos de Lewis/química , Compostos de Manganês/química , Óxidos/química , Peróxidos/química , Poluentes Químicos da Água/química , Cálcio/química , Catálise , Corantes/química , Oxidantes/química , Oxirredução , Soluções , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química
13.
Mol Ecol ; 29(3): 502-518, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31867742

RESUMO

Pupation site choice of Drosophila third-instar larvae is critical for the survival of individuals, as pupae are exposed to various biotic and abiotic dangers while immobilized during the 3-4 days of metamorphosis. This singular behavioural choice is sensitive to both environmental and genetic factors. Here, we developed a high-throughput phenotyping approach to assay the variation in pupation height in Drosophila melanogaster, while controlling for possibly confounding factors. We find substantial variation of mean pupation height among sampled natural stocks and we show that the Drosophila Genetic Reference Panel (DGRP) reflects this variation. Using the DGRP stocks for genome-wide association (GWA) mapping, 16 loci involved in determining pupation height could be resolved. The candidate genes in these loci are enriched for high expression in the larval central nervous system. A genetic network could be constructed from the candidate loci, which places scribble (scrib) at the centre, plus other genes known to be involved in nervous system development, such as Epidermal growth factor receptor (Egfr) and p53. Using gene disruption lines, we could functionally validate several of the initially identified loci, as well as additional loci predicted from network analysis. Our study shows that the combination of high-throughput phenotyping with a genetic analysis of variation captured from the wild can be used to approach the genetic dissection of an environmentally relevant behavioural phenotype.

14.
Blood Purif ; : 1-9, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31851984

RESUMO

BACKGROUND: The prognostic value of serum time-averaged albumin (TA-Alb) and time-averaged globulin (TA-Glo) combination on the peritonitis in peritoneal dialysis (PD) patients is unknown. METHODS: The patients who started PD treatment between July 2013 and 2018 were included. Serum Alb and globulin (Glo) were tested at baseline and monthly during follow-up. TA-Alb and TA-Glo were calculated until first peritonitis occurred or the end of the study. PD patients were divided into 4 groups based on the medians of TA-Alb and TA-Glo separately. Cox regression was conducted to identify the hazard ratios (HRs) of peritonitis among categorical groups. RESULTS: Three hundred and sixty-three patients were included and among them 109 patients experienced first peritonitis. Peritonitis patients had lower baseline Alb, TA-Alb, and TA-Glo levels and ultrafiltration volume. Multivariate cox regression analysis revealed that TA-Alb, TA-Glo, and baseline Alb were significantly associated with first peritonitis. The highest HR existed in Group 1 with lower Alb and lower Glo (HR 4.57, 95% CI 2.36-8.87, p < 0.001) compared with Group 4 with higher Alb and higher Glo. CONCLUSION: Lower TA-Glo is an independent risk factor for the first peritonitis in PD patients. Combined with lower TA-Alb will increase the predictive effect than separate factor alone.

15.
Medicine (Baltimore) ; 98(46): e17510, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31725605

RESUMO

Due to the complexity of Crohn's disease (CD), it is difficult to predict disease course with a single stratification factor or biomarker. A logistic regression (LR) model has been proposed by Guizzetti et al to stratify patients with CD-related surgical risk, which could help decision-making on disease treatment. However, there are no reports on relevant studies on Chinese population. The aim of the study is to present and validate a novel surgical predictive model to facilitate therapeutic decision-making for Chinese CD patients. Data was extracted from retrospective full-mode electronic medical records, which contained 239 CD patients and 1524 instances. Two sub-datasets were generated according to different attribute selection strategies, both of which were split into training and testing sets randomly. The imbalanced data in the training sets was addressed by synthetic minority over-sampling technique (SMOTE) algorithm before model development. Seven predictive models were employed using 5 popular machine learning algorithms: random forest (RF), LR, support vector machine (SVM), decision tree (DT) and artificial neural networks (ANN). The performance of each model was evaluated by accuracy, precision, F1-score, true negative (TN) rate, and the area under the receiver operating characteristic curve (AuROC). The result revealed that RF outperformed all other baseline models on both sub-datasets. The 10 leading risk factors for CD-related surgery returned from RF for attribute ranking were changes of radiology, presence of a fistula, presence of an abscess, no infliximab use, enteroscopy findings, C-reactive protein, abdominal pain, white blood cells, erythrocyte sedimentation rate and platelet count. The proposed machine learning model can accurately predict the risk of surgical intervention in Chinese CD patients, which could be used to tailor and modify the treatment strategies for CD patients in clinical practice.


Assuntos
Doença de Crohn/diagnóstico , Doença de Crohn/cirurgia , Técnicas de Apoio para a Decisão , Endoscopia do Sistema Digestório/estatística & dados numéricos , Modelos Anatômicos , Adulto , Algoritmos , Área Sob a Curva , Grupo com Ancestrais do Continente Asiático/estatística & dados numéricos , China , Árvores de Decisões , Feminino , Humanos , Modelos Logísticos , Aprendizado de Máquina/estatística & dados numéricos , Masculino , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Máquina de Vetores de Suporte
16.
Sci Rep ; 9(1): 17609, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31772341

RESUMO

Atmospheric water vapor increases as air temperature rises, which causes further warming. Thus, understanding the underlying causes of atmospheric water vapor change is vital in climate change research. Here, we conducted detection and attribution analyses of atmospheric precipitable water (PW) changes from 1973-2012 over China using an optimal fingerprinting method by comparing the homogenized radiosonde humidity data with CMIP5 model simulations. Results show that the increase in water vapor can be largely attributed to human activities. The effect of anthropogenic forcing (ANT) can be robustly detected and separated from the response to the natural external forcing (NAT) in the two-signal analysis. The moistening attributable to the ANT forcing explains most of the observed PW increase, while the NAT forcing leads to small moistening. GHGs are the primary moistening contributor responsible for the anthropogenic climate change, and the effect of GHGs can be also clearly detected and successfully attributed to the observed PW increases in a three-signal analysis. The scaling factor is used to adjust the CMIP5 model-projected PW changes over China and the observation-constrained future projections suggest that atmospheric water vapor may increase faster (slower) than that revealed by the raw simulations over whole (eastern) China.

17.
Small ; : e1902813, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31596546

RESUMO

Owing to their safety, high energy density, and long cycling life, all-solid-state lithium batteries (ASSLBs) have been identified as promising systems to power portable electronic devices and electric vehicles. Developing high-performance solid-state electrolytes is vital for the successful commercialization of ASSLBs. In particular, polymer-based composite solid electrolytes (PCSEs), derived from the incorporation of inorganic fillers into polymer solid electrolytes, have emerged as one of the most promising electrolyte candidates for ASSLBs because they can synergistically integrate many merits from their components. The development of PCSEs is summarized. Their major components, including typical polymer matrices and diverse inorganic fillers, are reviewed in detail. The effects of fillers on their ionic conductivity, mechanical strength, thermal/interfacial stability and possible Li+ -conductive mechanisms are discussed. Recent progress in a number of rationally constructed PCSEs by compositional and structural modulation based on different design concepts is introduced. Successful applications of PCSEs in various lithium-battery systems including lithium-sulfur and lithium-gas batteries are evaluated. Finally, the challenges and future perspectives for developing high-performance PCSEs are proposed.

18.
Comput Methods Programs Biomed ; : 105099, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31601442

RESUMO

OBJECTIVE: Understanding the three-dimensional (3D) spatial position and orientation of vessels and tumor(s) is vital in laparoscopic liver resection procedures. Augmented reality (AR) techniques can help surgeons see the patient's internal anatomy in conjunction with laparoscopic video images. METHOD: In this paper, we present an AR-assisted navigation system for liver resection based on a rigid stereoscopic laparoscope. The stereo image pairs from the laparoscope are used by an unsupervised convolutional network (CNN) framework to estimate depth and generate an intraoperative 3D liver surface. Meanwhile, 3D models of the patient's surgical field are segmented from preoperative CT images using V-Net architecture for volumetric image data in an end-to-end predictive style. A globally optimal iterative closest point (Go-ICP) algorithm is adopted to register the pre- and intraoperative models into a unified coordinate space; then, the preoperative 3D models are superimposed on the live laparoscopic images to provide the surgeon with detailed information about the subsurface of the patient's anatomy, including tumors, their resection margins and vessels. RESULTS: The proposed navigation system is tested on four laboratory ex vivo porcine livers and five operating theatre in vivo porcine experiments to validate its accuracy. The ex vivo and in vivo reprojection errors (RPE) are 6.04 ±â€¯1.85 mm and 8.73 ±â€¯2.43 mm, respectively. CONCLUSION AND SIGNIFICANCE: Both the qualitative and quantitative results indicate that our AR-assisted navigation system shows promise and has the potential to be highly useful in clinical practice.

19.
J Virol ; 93(23)2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31534045

RESUMO

Type A and type B influenza viruses (FluA and FluB viruses) are two major human pathogens that share common structural and functional features. FluA and FluB viruses can reassort within each type but never between the types. Here, we bioinformatically analyzed all promoter sequences of FluA and FluB viruses and confirmed the presence of the type-specific promoter elements. We then studied the promoter elements with cell-based in vivo assays and an in vitro replication initiation assay. Our results identified, for the first time, a type-specific promoter element-the nucleotide at position 5 in the 3' end of the viral RNA (vRNA)-that plays a key role(s) in modulating polymerase activity in a type-specific manner. Interestingly, swapping the promoter element between FluA and FluB recombinant viruses showed different tolerances: the replacement of FluA virus-specific U5 with FluB virus-specific C5 in influenza virus A/WSN/33 (H1N1) could be reverted to U5 after 2 to 3 passages, while the replacement of FluB virus-specific C5 with FluA virus-specific U5 in influenza virus B/Yamagata/88 could be maintained, but with significantly reduced replication efficiency. Therefore, our findings indicate that the nucleotide variation at position 5 in the 3' end of the vRNA promoter between FluA and FluB viruses contributes to their RNP incompatibility, which may shed new light on the mechanisms of intertypic exclusion of reassortment between FluA and FluB viruses.IMPORTANCE Genetic reassortment of influenza virus plays a key role in virus evolution and the emergence of pandemic strains. The reassortment occurs extensively within either FluA or FluB viruses but never between them. Here, we bioinformatically compared available promoter sequences of FluA and FluB viruses and confirmed the presence of the type-specific promoter elements. Our in vivo and in vitro mutagenesis studies showed that a type-specific promoter element-the nucleotide at position 5 in the 3' end of vRNA promoters-plays key roles in modulating polymerase activity. Interestingly, FluA and FluB viruses showed different tolerances upon key promoter element swapping in the context of virus infections. We concluded that the nucleotide at position 5 in the 3' end of the vRNA promoters of FluA and FluB viruses is a critical type-specific determinant. This work has implications for further elucidating the mechanisms of the intertypic exclusion of reassortment between FluA and FluB viruses.

20.
Bioresour Technol ; 291: 121849, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31387051

RESUMO

Anaerobic digestion (AD) has been widely applied as an economic option for food waste (FW) treatment. In this study, the group treated with ethanol pre-fermentation (EP) for 12 h (EP12) exhibited the highest cumulative biogas yield (206 mL/g-volatile solid) during AD process and therefore it was used to illuminate the underlying metabolic processes of AD with EP. Carbon isotope labeled glucose was supplemented to FW substrate, and the EP process was found to alleviate the acidification inhibition with conducting extremely high carbon flux towards ethanol formation (43.7%). Then an efficient acetogenesis phase was also observed in EP12 group, because of high carbon conversion rate from ethanol to acetate. Overall, higher carbon conversion rate to methane (90.1%) during methanogenesis was found in the AD system with EP than in the control experiment (80.3%). Thus, we quantitatively confirmed that EP affects the AD metabolism of FW in terms of carbon flow distribution.


Assuntos
Alimentos , Metano/biossíntese , Anaerobiose , Biocombustíveis , Isótopos de Carbono , Etanol/metabolismo , Fermentação , Marcação por Isótopo
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