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Sustained low diffusing capacity in hepatopulmonary syndrome after liver transplantation

World Journal of Gastroenterology 2006年第36期12卷 5878-5883页

作者： Graciela Martínez-Pallí Federico P Gómez Joan A Barberà Miquel Navasa Josep Roca robert rodríguez-roisin Felip Burgos Conchi Gistau Serveis de Pneumologia Anestesiologia and Hepatologia. Institut d'Investigacions Biomèdiques August Pi i Sunyer Hospital Clínic Universitat de Barcelona Barcelona Spain Serveis de Pneumologia Anestesiologia and Hepatologia. Institut d’Investigacions Biomèdiques August Pi i Sunyer Hospital Clínic Universitat de Barcelona Barcelona Spain

AIM: To study the presence of sustained low diffusing capacity (DLCO) after liver transplantation (LT) in patients with hepatopulmonary syndrome (HPS).METHODS: Six patients with mild-to-severe HPS and 24 without HPS who underwent LT were prospectively followed before and after LT at mid-term (median, 15 mo). HPS patients were also assessed at long-tem (median, 86 mo).RESULTS: Before LT, HPS patients showed lower PaO2 (71 ± 8 mmHg), higher AaPO2 (43 ± 10 mmHg) and lower DLCO (54% ± 9% predicted), due to a combination of moderate-to-severe ventilation-perfusion (VA/Q) imbalance, mild shunt and diffusion limitation, than non-HPS patients (94 ± 4 mmHg and 19 ± 3 mmHg, and 85% ± 3% predicted, respectively) (P < 0.05 each). Seven non-HPS patients had also reduced DLCO (70% ± 4% predicted).At mid- and long-term after LT, compared to pre-LT, HPS patients normalized PaO2 (91 ± 3 mmHg and 87 ± 5 mmHg), AaPO2 (14 ± 3 mmHg and 23 ± 5 mmHg) and all VA/Q descriptors (P < 0.05 each) without changes in DLCO (53% ± 8% and 56% ± 7% predicted, respectively). Post-LT DLCO in non-HPS patients with pre-LT low DLCO was unchanged (75% ± 6% predicted).CONCLUSION: While complete VA/Q resolution in HPS indicates a reversible functional disturbance, sustained low DLCO after LT also present in some non-HPS patients, points to persistence of sub-clinical liver-induced pulmonary vascular changes.

关键词：容量肝移植一氧化碳肺交换

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Nitrate reduction capacity of the oral microbiota is impaired in periodontitis:potential implications for systemic nitric oxide availability

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International Journal of Oral Science 2024年第1期16卷 52-61页

作者： Bob T.Rosier William Johnston Miguel Carda-Diéguez Annabel Simpson Elena Cabello-Yeves Krystyna Piela robert Reilly Alejandro Artacho Chris Easton Mia Burleigh Shauna Culshaw Alex Mira Department of Genomics and Health FISABIO FoundationCenter for Advanced Research in Public HealthValenciaSpain Department of Biological and Biomedical Sciences Glasgow Caledonian UniversityGlasgowUK Oral Sciences University of Glasgow Dental SchoolSchool of MedicineDentistry and NursingCollege of MedicalVeterinary and Life SciencesUniversity of GlasgowGlasgowUK Sport and Physical Activity Research Institute University of the West of ScotlandBlantyreScotland Instituto de Biomedicina de Valencia Consejo Superior de Investigaciones Científicas(IBV-CSIC)ValenciaSpain CIBER Center for Epidemiology and Public Health MadridSpain

The reduction of nitrate to nitrite by the oral microbiota has been proposed to be important for oral health and results in nitric oxide formation that can improve cardiometabolic conditions. Studies of bacterial composition in subgingival plaque suggest that nitrate-reducing bacteria are associated with periodontal health, but the impact of periodontitis on nitrate-reducing capacity(NRC)and, therefore, nitric oxide availability has not been evaluated. The current study aimed to evaluate how periodontitis affects the NRC of the oral microbiota. First, 16S rRNA sequencing data from five different countries were analyzed, revealing that nitratereducing bacteria were significantly lower in subgingival plaque of periodontitis patients compared with healthy individuals(P < 0.05 in all five datasets with n = 20–82 samples per dataset). Secondly, subgingival plaque, saliva, and plasma samples were obtained from 42 periodontitis patients before and after periodontal treatment. The oral NRC was determined in vitro by incubating saliva with 8 mmol/L nitrate(a concentration found in saliva after nitrate-rich vegetable intake) and compared with the NRC of 15healthy individuals. Salivary NRC was found to be diminished in periodontal patients before treatment(P < 0.05) but recovered to healthy levels 90 days post-treatment. Additionally, the subgingival levels of nitrate-reducing bacteria increased after treatment and correlated negatively with periodontitis-associated bacteria(P < 0.01). No significant effect of periodontal treatment on the baseline saliva and plasma nitrate and nitrite levels was found, indicating that differences in the NRC may only be revealed after nitrate intake. Our results suggest that an impaired NRC in periodontitis could limit dietary nitrate-derived nitric oxide levels, and the effect on systemic health should be explored in future studies.

关键词： impaired intake nitrate

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Necrotic enteritis and antibiotic-free production of broiler chickens:Challenges in testing and using alternative products

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Animal Nutrition 2024年第1期16卷 288-298页

作者： robert J.Moore School of Science RMIT University

The global trend towards raising broiler chickens without the use of in-feed antibiotics(IFAs) means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously provided. IFAs supported the productivity performance of chickens and played a key role in maintaining their health. Necrotic enteritis(NE) is an important disease of broilers that affects health,productivity, and welfare, and was previously well controlled by IFAs. However, with the reduction in IFA use, NE is resurgent in some countries. Vaccines and various feed additives, including pre-, pro-, and postbiotics, phytobiotics, fatty acids, and phage therapies have been introduced as alternative methods of NE control. While some of these feed additives have specific activity against the NE pathogen, Clostridium perfringens, most have the more general goal of reinforcing gut health. Extensive reviews of the effects of many of these feed additives on gut health have been published recently. Hence, rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative NE treatments and translating laboratory research to real world commercial production settings. The review is based on the author's particular experience,reading, thoughts, and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these issues. It is put forward to stimulate thinking and discussion on the issues covered.

关键词： Necrotic enteritis

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Predicting the coefficient of friction in a sliding contact by applying machine learning to acoustic emission data

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Friction 2024年第6期12卷 1299-1321页

作者： robert GUTIERREZ Tianshi FANG robert MAINWARING Tom REDDYHOFF Tribology Group Department of Mechanical EngineeringImperial College LondonExhibition RoadLondon SW72AZUK Shell Global Solutions(US)Inc.Shell Technology Center Houston 3333 Highway 6 SouthHoustonTX 77082USA Shell International Petroleum Company Limited Shell CentreYork RoadLondon SE17NAUK

It is increasingly important to monitor sliding interfaces within machines,since this is where both energy is lost,and failures occur.Acoustic emission(AE)techniques offer a way to monitor contacts remotely without requiring transparent or electrically conductive materials.However,acoustic data from sliding contacts is notoriously complex and difficult to interpret.Herein,we simultaneously measure coefficient of friction(with a conventional force transducer)and acoustic emission(with a piezoelectric sensor and high acquisition rate digitizer)produced by a steel‒steel rubbing contact.Acquired data is then used to train machine learning(ML)algorithms(e.g.,Gaussian process regression(GPR)and support vector machine(SVM))to correlated acoustic emission with friction.ML training requires the dense AE data to first be reduced in size and a range of processing techniques are assessed for this(e.g.,down-sampling,averaging,fast Fourier transforms(FFTs),histograms).Next,fresh,unseen AE data is given to the trained model and the resulting friction predictions are compared with the directly measured friction.There is excellent agreement between the measured and predicted friction when the GPR model is used on AE histogram data,with root mean square(RMS)errors as low as 0.03 and Pearson correlation coefficients reaching 0.8.Moreover,predictions remain accurate despite changes in test conditions such as normal load,reciprocating frequency,and stroke length.This paves the way for remote,acoustic measurements of friction in inaccessible locations within machinery to increase mechanical efficiency and avoid costly failure/needless maintenance.

关键词： acoustic emission condition monitoring friction machine learning Gaussian process regression support vector machine

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A detailed rock density model of the Hong Kong territories

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Geodesy and Geodynamics 2024年第1期15卷 75-81页

作者： Albertini Nsiah Ababio robert Tenzer Department of Land Surveying and Geo-Informatics Hong Kong Polytechnic UniversityHong KongChina

We used the geological map and published rock density measurements to compile the digital rock density model for the Hong Kong territories.We then estimated the average density for the whole territory.According to our result,the rock density values in Hong Kong vary from 2101 to 2681 kg·m^(-3).These density values are typically smaller than the average density of 2670 kg·m^(-3),often adopted to represent the average density of the upper continental crust in physical geodesy and gravimetric geophysics applications.This finding reflects that the geological configuration in Hong Kong is mainly formed by light volcanic formations and lava flows with overlying sedimentary deposits at many locations,while the percentage of heavier metamorphic rocks is very low(less than 1%).This product will improve the accuracy of a detailed geoid model and orthometric heights.

关键词： Density model Rock types Gravimetric modeling Hong Kong

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The concept of gene therapy for glaucoma:the dream that has not come true yet

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Neural Regeneration Research 2024年第1期19卷 92-99页

作者： robert Sulak Xiaonan Liu Adrian Smedowski Department of Physiology Faculty of Medical Sciences in KatowiceMedical University of Silesia in KatowiceKatowicePoland Institute of Biotechnology HiLIFEUniversity of HelsinkiHelsinkiFinland GlaucoTech Co. KatowicePoland

Gene therapies,despite of being a relatively new therapeutic approach,have a potential to become an important alternative to current treatment strategies in glaucoma.Since glaucoma is not considered a single gene disease,the identified goals of gene therapy would be rather to provide neuroprotection of retinal ganglion cells,especially,in intraocular-pressure-independent manner.The most commonly reported type of vector for gene delivery in glaucoma studies is adeno-associated virus serotype 2 that has a high tro pism to retinal ganglion cells,res ulting in long-term expression and low immunogenic profile.The gene thera py studies recruit inducible and genetic animal models of optic neuropathy,like DBA/2J mice model of high-tension glaucoma and the optic nerve crush-model.Reported gene therapy-based neuroprotection of retinal ganglion cells is targeting specific genes translating to growth factors(i.e.,brain derived neurotrophic factor,and its receptor TrkB),regulation of apoptosis and neurodegeneration(i.e.,Bcl-xl,Xiap,FAS system,nicotinamide mononucleotide adenylyl transferase 2,Digit3 and Sarm1),immunomodulation(i.e.,Crry,C3 complement),modulation of neuroinflammation(i.e.,e rythropoietin),reduction of excitotoxicity(i.e.,Com KIlα)and transcription regulation(i.e.,Max,Nrf2).On the other hand,some of gene therapy studies focus on lowering intra ocular pressure,by impacting genes involved in both,decreasing aqueous humor production(i.e.,aquaporin 1),and increasing outflow facility(i.e.,COX2,prostaglandin F2a receptor,RhoA/RhoA kinase signaling pathway,MMP1,Myocilin).The goal of this review is to summarize the current stateof-art and the direction of development of gene therapy strategies for glaucomatous neuropathy.

关键词： adeno-associated virus gene editing gene therapy glaucoma IOP lowering IOP-independent mechanisms neuroprotection optic nerve optic neuropathy retinal ganglion cells

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Advances in discovery of novel investigational agents for functional cure of chronic hepatitis B:A comprehensive review of phases II and III therapeutic agents

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World Journal of Hepatology 2024年第3期16卷 331-343页

作者： robert Lam Joseph K Lim Section of Digestive Diseases Yale University School of MedicineNew HavenCT 06520United States

Chronic hepatitis B virus(HBV)infection affects over 295 million people globally and an estimated 1.6 million people in the United States.It is associated with significant morbidity and mortality due to cirrhosis,liver failure,and liver cancer.Antiviral therapy with oral nucleos(t)ide analogues is associated with high rates of virologic suppression,which in turn has been associated with a decreased risk of liver complications.However,current antiviral regimens are limited by concerns with adverse effects,adherence,resistance,long-term treatment,and ongoing risk for liver events.Novel investigational agents are currently in development and are targeted at achieving functional cure with sustained hepatitis B surface antigen(HBsAg)loss and suppression of HBV DNA.Herein we review key evidence from phases II and III trials defining the efficacy and safety profiles for key investigational agents for functional cure of chronic hepatitis B,including core/capsid inhibitors,entry inhibitors,RNA interference(siRNA/ASO),HBsAg inhibitors,Toll-like receptor agonists,checkpoint inhibitors,and therapeutic vaccines.

关键词： Hepatitis B virus Treatment Clinical trials RNA interference Entry inhibitors Core inhibitors Immunomodulators

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Glycolysis and glucose metabolism as a target for bioenergetic and neuronal protection in glaucoma

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Neural Regeneration Research 2024年第8期19卷 1637-1638页

作者： Pete A.Williams robert J.Casson Department of Clinical Neuroscience Division of Eye and VisionSt.Erik Eye HospitalKarolinska InstitutetStockholmSweden Ophthalmic Research Laboratories Discipline of Ophthalmology and Visual SciencesUniversity of AdelaideAdelaideAustralia

Vision is arguably our most valued sense,yet approximately 340 million people globally suffer blindness or moderate visual impairment,highlighting the need to further develop and advance treatments for ophthalmic diseases.Glaucoma refers to a group of ocular disorders united by a clinically characteristic optic neuropathy with associated retinal ganglion cell loss.

关键词： metabolism glaucoma globally

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Optimization of product characteristics of porous carbon agglomerates using a design of experiments in fluidized bed agglomeration

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Particuology 2024年第6期89卷 258-269页

作者： Martin Oelofse robert Rack Marcelle Hilden Peter Langguth Department of Pharmaceutical Technology and Biopharmaceutics Johannes Gutenberg UniversityMainzGermany Carbon Advanced Solutions GmbH HeuchelheimGermany

Spraying parameters during particle agglomeration processes can affect the agglomeration kinetics and particle growth.This study was conducted to better understand the influence of the spraying parameters in a fluidized bed wet agglomeration process,and the influence on the stability characteristics of carbon tablets.A formulation based on fine carbon and peroxide powder,as well as carboxymethyl cellulose as a binder,was used to produce agglomerates in a first production step.Thereafter in a second production step carbon tablets with a high porosity were molded for the customer goods industry.The optimization of the compressive strength of these carbon tablets was the goal of the trials.Carbon agglomerates were produced with a laboratory scale granulator called“ProCell”and were compressed with a five-cavity mechanical press.The screening of the agglomeration process parameters and their influence on the agglomerates quality,as well as the performance characteristics of the carbon tablets,were investigated using a multilevel factorial design.The experimental runs were done by varying atomized air pressure and feed rate of the fluid.This was determined by the design model.The findings of the statistical trials showed that low atomized air pressure and a low feed rate lead to a higher tablet compressive strength.

关键词： Wet agglomeration Fluidized bed Design of experiments Carbon agglomerates and tablets

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The influence of various grease compositions and silver nanoparticle additives on electrically induced rolling-element bearing damage

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Friction 2024年第4期12卷 796-811页

作者： Samuel BOND robert L.JACKSON German MILLS Department of Chemistry and Biochemistry Auburn UniversityAuburn 36849-5412USA Department of Mechanical Engineering Auburn UniversityAuburn 36849-5412USA

Leakage currents accelerate surface degradation of metal contacts via small scale arcing across lubricating films,but recent observations suggest that metallic nanoparticle additives in lubricants may be useful to improve contact performance.These findings prompted a study that examined electrically induced surface pitting of steel contacts in the presence of several lubricating greases including some containing nanometer-sized colloidal silver(Ag)particles.Reciprocating rolling sphere-on-disk experiments were conducted under electro-tribological loads employing polyurea greases derived from mineral and synthetic base oils with and without additives.Friction forces and electrical resistance were monitored continuously during the tests;surface changes were characterized by means of optical spectroscopy,stylus profilometry,and scanning electron microscopy(SEM)including compositional analysis using energy dispersive spectroscopy(EDS).The observations demonstrate that surface pitting induced by arcing occurs mainly at the points were the rolling motion changes direction and that eroded metal is deposited along the wear grove.Micron-sized pits are formed which contain carbon and oxygen indicating that arcing causes decomposition of the hydrocarbon lubricants.Numerous findings indicate a significant inhibition of pitting is induced by the Ag nanoparticles;some greases containing other additives exhibit a similar,although less pronounced,effect.

关键词： electric motor bearings wheel bearings electric vehicles arcing electrically induced bearing damage pitting leakage current stray current

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