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The rise of drug resistance has become a global crisis, with >1 million deaths due to resistant bacterial infections each year. Pseudomonas aeruginosa, in particular, remains a serious problem with limited solutions due to complex resistance mechanisms that now lead to more than 32,000 multidrug-resistant (MDR) infections and over 2000 deaths in the U.S. annually. While the emergence of resistant bacteria has become ominously common, identification of useful new drug classes has been limited over the past over 40 years. We found that a potential novel therapeutic, the peptide-mimetic TM5, is effective at killing P. aeruginosa and displays sufficiently low toxicity in mammalian cells to allow for use in treatment of infections. Interestingly, TM5 kills P. aeruginosa more rapidly than traditional antibiotics, within 30-60 min in vitro, and is effective against a range of clinical isolates, including extensively drug resistant strains. In vivo, TM5 significantly reduced bacterial load in the lungs within 24 h compared to untreated mice and demonstrated few adverse effects. Taken together, these observations suggest that TM5 shows promise as an alternative therapy for MDR P. aeruginosa respiratory infections.
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Modelos Animales de Enfermedad , Infecciones por Pseudomonas , Pseudomonas aeruginosa , Infecciones del Sistema Respiratorio , Animales , Pseudomonas aeruginosa/efectos de los fármacos , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Ratones , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/microbiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Femenino , Humanos , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Péptidos/farmacología , Péptidos/uso terapéuticoRESUMEN
New antiviral agents are essential to improving treatment and control of SARS-CoV-2 infections that can lead to the disease COVID-19. Antimicrobial peptoids are sequence-specific oligo-N-substituted glycine peptidomimetics that emulate the structure and function of natural antimicrobial peptides but are resistant to proteases. We demonstrate antiviral activity of a new peptoid (TM9) against the coronavirus, murine hepatitis virus (MHV), as a closely related model for the structure and antiviral susceptibility profile of SARS-CoV-2. This peptoid mimics the human cathelicidin LL-37, which has also been shown to have antimicrobial and antiviral activity. In this study, TM9 was effective against three murine coronavirus strains, demonstrating that the therapeutic window is large enough to allow the use of TM9 for treatment. All three isolates of MHV generated infection in mice after 15 min of exposure by aerosol using the Madison aerosol chamber, and all three viral strains could be isolated from the lungs throughout the 5-day observation period post-infection, with the peak titers on day 2. MHV-A59 and MHV-A59-GFP were also isolated from the liver, heart, spleen, olfactory bulbs, and brain. These data demonstrate that MHV serves as a valuable natural murine model of coronavirus pathogenesis in multiple organs, including the brain.
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Numerous experimental and theoretical studies undertaken to determine the effective stress coefficient for seismic velocities in rocks stem from the importance of this geomechanical parameter both for monitoring changes in rock saturation and pore pressure distribution in connection with reservoir production, and for overpressure prediction in reservoirs and formations from seismic data. The present work pursues a task to determine, in the framework of a low-frequency laboratory study, the dependence of the elastic moduli of n-decane-saturated sandstone on the relationship between pore and confining pressures. The study was conducted on a sandstone sample with high quartz and notable clay content in a quasi-static regime when a 100 mL tank filled with n-decane was directly connected to the pore space of the sample. The measurements were carried out at a seismic frequency of 2 Hz and strains, controlled by semiconductor strain gauges, not exceeding 10-6. The study was performed using a forced-oscillation laboratory apparatus utilizing the stress-strain relationship. The dynamic elastic moduli were measured in two sets of experiments: at constant pore pressures of 0, 1, and 5 MPa and differential pressure (defined as a difference between confining and pore pressures) that varied from 3 to 19 MPa; and at a constant confining pressure of 20 MPa and pore pressure that varied from 1 to 17 MP. It was shown that the elastic moduli obtained in the measurements were in good agreement with the Gassmann moduli calculated for the range of differential pressures used in our experiments, which corresponds to the effective stress coefficient equal to unity.
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The rise of drug resistance has become a global crisis, with >1 million deaths due to resistant bacterial infections each year. Pseudomonas aeruginosa, in particular, remains a serious problem with limited solutions due to complex resistance mechanisms that now lead to more than 32,000 multidrug-resistant (MDR) infections and over 2,000 deaths annually. While the emergence of resistant bacteria has become concerningly common, identification of useful new drug classes has been limited over the past 40+ years. We found that a potential novel therapeutic, the peptide-mimetic TM5, is effective at killing P. aeruginosa and displays sufficiently low toxicity for mammalian cells to allow for use in treatment of infections. Interestingly, TM5 kills P. aeruginosa more rapidly than traditional antibiotics, within 30-60 minutes in vitro , and is effective against a range of clinical isolates. In vivo , TM5 significantly reduced bacterial load in the lungs within 24 hours compared to untreated mice and demonstrated few adverse effects. Taken together, these observations suggest that TM5 shows promise as an alternative therapy for MDR P. aeruginosa respiratory infections.
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BACKGROUND: A large epidemic, such as that observed with SARS-CoV-2, seriously challenges available hospital capacity, and this would be augmented by infection of healthcare workers (HCW). Bacillus Calmette-Guérin (BCG) is a vaccine against tuberculosis, with protective non-specific effects against other respiratory tract infections in vitro and in vivo. Preliminary analyses suggest that regions of the world with existing BCG vaccination programs have lower incidence and mortality from COVID-19. We hypothesize that BCG vaccination can reduce SARS-CoV-2 infection and disease severity. METHODS: This will be a placebo-controlled adaptive multi-center randomized controlled trial. A total of 1800 individuals considered to be at high risk, including those with comorbidities (hypertension, diabetes, obesity, reactive airway disease, smokers), racial and ethnic minorities, elderly, teachers, police, restaurant wait-staff, delivery personnel, health care workers who are defined as personnel working in a healthcare setting, at a hospital, medical center or clinic (veterinary, dental, ophthalmology), and first responders (paramedics, firefighters, or law enforcement), will be randomly assigned to two treatment groups. The treatment groups will receive intradermal administration of BCG vaccine or placebo (saline) with groups at a 1:1 ratio. Individuals will be tracked for evidence of SARS-CoV-2 infection and severity as well as obtaining whole blood to track immunological markers, and a sub-study will include cognitive function and brain imaging. The majority of individuals will be followed for 6 months, with an option to extend for another 6 months, and the cognitive sub-study duration is 2 years. We will plot Kaplan-Meier curves that will be plotted comparing groups and hazard ratios and p-values reported using Cox proportional hazard models. DISCUSSION: It is expected this trial will allow evaluation of the effects of BCG vaccination at a population level in high-risk healthcare individuals through a mitigated clinical course of SARS-CoV-2 infection and inform policy making during the ongoing epidemic. TRIAL REGISTRATION: ClinicalTrials.gov NCT04348370. Registered on April 16, 2020.
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COVID-19 , SARS-CoV-2 , Humanos , Anciano , COVID-19/prevención & control , Vacuna BCG , Vacunación , Personal de Salud , InmunidadRESUMEN
Thermodynamic properties of fluids confined in nanopores differ from those observed in the bulk. To investigate the effect of nanoconfinement on water compressibility, we perform water sorption experiments on two nanoporous glass samples while concomitantly measuring the speed of longitudinal and shear ultrasonic waves in these samples. These measurements yield the longitudinal and shear moduli of the water-laden nanoporous glass as a function of relative humidity that we utilize in the Gassmann theory to infer the bulk modulus of the confined water. This analysis shows that the bulk modulus (inverse of compressibility) of confined water is noticeably higher than that of the bulk water at the same temperature. Moreover, the modulus exhibits a linear dependence on the Laplace pressure. The results for water, which is a polar fluid, agree with previous experimental and numerical data reported for nonpolar fluids. This similarity suggests that irrespective of intermolecular forces, confined fluids are stiffer than bulk fluids. Accounting for fluid stiffening in nanopores may be important for accurate interpretation of wave propagation measurements in fluid-filled nanoporous media, including in petrophysics, catalysis, and other applications, such as in porous materials characterization.
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Seismic velocities and elastic moduli of rocks are known to vary significantly with applied stress, which indicates that these materials exhibit nonlinear elasticity. Monochromatic waves in nonlinear elastic media are known to generate higher harmonics and combinational frequencies. Such effects have the potential to be used for broadening the frequency band of seismic sources, characterization of the subsurface, and safety monitoring of civil engineering infrastructure. However, knowledge on nonlinear seismic effects is still scarce, which impedes the development of their practical applications. To explore the potential of nonlinear seismology, we performed three experiments: two in the field and one in the laboratory. The first field experiment used two vibroseis sources generating signals with two different monochromatic frequencies. The second field experiment used a surface orbital vibrator with two eccentric motors working at different frequencies. In both experiments, the generated wavefield was recorded in a borehole using a fiber-optic distributed acoustic sensing cable. Both experiments showed combinational frequencies, harmonics, and other intermodulation products of the fundamental frequencies both on the surface and at depth. Laboratory experiments replicated the setup of the field test with vibroseis sources and showed similar nonlinear combinations of fundamental frequencies. Amplitudes of the nonlinear signals observed in the laboratory showed variation with the saturating fluid. These results confirm that nonlinear components of the wavefield propagate as body waves, are likely to generate within rock formations, and can be potentially used for reservoir fluid characterization.
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Acústica , Planeta Tierra , Elasticidad , Módulo de ElasticidadRESUMEN
Molecular dynamics simulations of mixtures of N,N-dimethylformamide (DMF) with water of various compositions, covering the entire composition range, are performed on the canonical (N,V,T) ensemble. The local structure of the mixtures is analyzed in terms of radial distribution functions and the contributions of the first five neighbors to them, various order parameters of the water molecules around each other, and properties of the Voronoi polyhedra of the molecules. The analyses lead to the following main conclusions. The two molecules are mixing with each other even on the molecular scale; however, small self-aggregates of both components persist even at their small mole fraction values. In particular, water-water H-bonds exist in the entire composition range, while water clusters larger than 3 and 2 molecules disappear above the DMF mole fraction values of about 0.7 and 0.9, respectively. The O atoms of the DMF molecules can well replace water O atoms in the hydrogen-bonding network. Further, the H-bonding structure is enhanced by the presence of the hydrophobic CH3 groups of the DMF molecules. On the other hand, the H-bonding network of the molecules gradually breaks down upon the addition of DMF to the system due to the lack of H-donating groups of the DMF molecules. Finally, in neat DMF, the molecules form weak, CH-donated H-bonds with each other; however, these H-bonds disappear upon the addition of water due to the increasing competition with the considerably stronger OH-donated H-bonds DMF can form with the water molecules.
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Dimetilformamida , Agua , Dimetilformamida/química , Enlace de Hidrógeno , Simulación de Dinámica Molecular , Agua/químicaRESUMEN
Tuberculosis is one of the most frequent causes of death in humans worldwide. One of the primary reasons tuberculosis remains a public health threat is that diagnosis can take weeks to months, is often not very sensitive and cannot be accomplished in many remote environments. A rapid, sensitive and inexpensive point-of-care (POC) diagnostic would have a major impact on tuberculosis eradication efforts. The tuberculosis diagnostic system REFtb is based on specific detection of the constitutively expressed ß-lactamase (BlaC) in Mycobacterium tuberculosis using a custom fluorogenic substrate designated as CDG-3. REFtb has potential as a diagnostic for tuberculosis that could be very inexpensive (
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PURPOSE: Early diagnosis of bronchiolitis in infants allows for risk stratification for central apnea, and, when available, the timely initiation of antiviral treatment. An animal model could demonstrate if earlier diagnosis is possible with ultrasound than with clinical exam. Even if possible, translating this to pediatrics would require observations from undifferentiated human infants. METHODS: We used serial daily clinical and lung ultrasound exams in a bovine calf model (Bos taurus) of respiratory syncytial virus bronchiolitis. Ultrasound and clinical examiners were blinded to each other's findings and the treatments used in 24 calves. Time to diagnosis was compared using Kaplan-Meier curves. A case series of human infants with upper respiratory tract infections, without clinical signs of bronchiolitis, and in whom lung ultrasound was performed, was extracted from hospital records. RESULTS: In the bovine model, lung ultrasound findings emerged earlier and lasted later than auscultatory findings. Relying on auscultation, 5/24 (21%) of animals were diagnosed by post-inoculation day 5 whereas 24/24 (100%) were diagnosed by ultrasound. We identified seven infants in whom lung ultrasound was used to diagnose bronchiolitis before adventitial lung sounds emerged. Three of these subsequently developed typical clinical findings of bronchiolitis in the hospital. Two had alternative explanations for their abnormal lung ultrasounds (both required surgical intervention). Two were discharged and required no further medical attention. CONCLUSION: Lung ultrasound allowed earlier diagnosis of bronchiolitis than clinical exam in the bovine model. In the human case series this was also true, but alternative causes of abnormal ultrasound were frequent.
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Experimentación Animal , Bronquiolitis , Humanos , Lactante , Niño , Animales , Bovinos , Bronquiolitis/diagnóstico por imagen , Bronquiolitis/terapia , Pulmón/diagnóstico por imagen , Auscultación , Diagnóstico PrecozRESUMEN
PURPOSE: Bronchiolitis is a very common acute lung disease in infants caused commonly by respiratory syncytial virus (RSV). Point-of-care lung ultrasound is increasingly used in clinical care but proof that ultrasound reflects histological disease is lacking. Bovine calves are a good model for RSV bronchiolitis. We answered the following two questions: (1) does point-of-care lung ultrasound reflect lung pathology at the histological level in a bovine calf model of bronchiolitis? and (2) are point-of-care lung ultrasound images in human infants similar to those obtained in calves? METHODS: We experimentally infected 24 five to six-week-old bovine calves with RSV and compared six window lung ultrasound with lung histology10 days after inoculation. The calves were treated with antivirals and antipyretics leading to variable severity of illness. We used canonical discriminant analysis to determine if abnormal lung ultrasound findings reflected different histological findings. We compared the ultrasounds obtained from the calves with ultrasounds obtained from 10 human infants who were diagnosed clinically with bronchiolitis. RESULTS: Canonical discriminant analysis generally demonstrated good class separation based on the maximal severity of ultrasound finding in each acoustic window. Lung ultrasound performed poorly at detecting bronchopneumonia. Bovine ultrasounds looked similar to human infant lung ultrasounds. CONCLUSION: Point-of-care lung ultrasound abnormalities reflect lung pathology at the histological level in a bovine calf model of bronchiolitis. Point-of-care lung ultrasound images in human infants are similar to those obtained in calves.
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Bronquiolitis , Infecciones por Virus Sincitial Respiratorio , Enfermedad Aguda , Animales , Bronquiolitis/diagnóstico por imagen , Bronquiolitis/patología , Bovinos , Humanos , Lactante , Pulmón/diagnóstico por imagen , Infecciones por Virus Sincitial Respiratorio/diagnóstico por imagen , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Infecciones por Virus Sincitial Respiratorio/patología , Virus Sincitiales RespiratoriosRESUMEN
Bovine respiratory syncytial virus (RSV) has substantial morbidity in young calves, and closely parallels human RSV in infants. We performed a randomized controlled trial in five to six-week-old Holstein calves (Bos taurus). comparing fusion protein inhibitor (FPI) and non-steroidal anti-inflammatory drug (NSAID) singly and in combination at three and five days after experimental BRSV infection. Thirty-six calves received one of six treatments; Ibuprofen started on day 3, Ibuprofen started on day 5, FPI started on day 5, FPI and Ibuprofen started on day 3, FPI and Ibuprofen started on day 5, or placebo. We have previously reported significant clinical benefits when combined FPI and NSAID treatment was started at three and five days after bovine RSV infection. Necropsy was performed on Day 10 following infection and hematoxylin and eosin staining was performed on sections from each lobe. Histology was described using a four-point scale. We performed canonical discrimination analysis (CDA) to determine the structural level where differences between treatments occurred and mixed effects regression to estimate effect sizes. Separation from placebo was maximal for dual therapy at the levels of the alveolus, septum, and bronchus in CDA. We found that the clinical benefits of combined FPI and NSAID treatment of BRSV extend at least partially from histopathological changes in the lung when treatment was started three days after infection. We found decreased lung injury when ibuprofen was started as monotherapy on day 3, but not day 5 following infection. Combined therapy with both an FPI and ibuprofen was always better than ibuprofen alone. We did not prove that the clinical benefits seen starting FPI and ibuprofen five days after infection can be solely explained by histopathological differences as identified on H&E staining.
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Antiinflamatorios no Esteroideos/uso terapéutico , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Animales , Bovinos , Neumonía/tratamiento farmacológico , Carga ViralRESUMEN
[This corrects the article DOI: 10.1371/journal.pone.0230245.].
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Bovine Respiratory Syncytial virus (BRSV) is one of the major infectious agents in the etiology of the bovine respiratory disease complex. BRSV causes a respiratory syndrome in calves, which is associated with severe bronchiolitis. In this study we describe the effect of treatment with antiviral fusion protein inhibitor (FPI) and ibuprofen, on gene expression in lung tissue of calves infected with BRSV. Calves infected with BRSV are an excellent model of human RSV in infants: we hypothesized that FPI in combination with ibuprofen would provide the best therapeutic intervention for both species. The following experimental treatment groups of BRSV infected calves were used: 1) ibuprofen day 3-10, 2) ibuprofen day 5-10, 3) placebo, 4) FPI day 5-10, 5) FPI and ibuprofen day 5-10, 6) FPI and ibuprofen day 3-10. All calves were infected with BRSV on day 0. Daily clinical evaluation with monitoring of virus shedding by qRT-PCR was conducted. On day10 lung tissue with lesions (LL) and non-lesional (LN) was collected at necropsy, total RNA extracted, and RNA sequencing performed. Differential gene expression analysis was conducted with Gene ontology (GO) and KEGG pathway enrichment analysis. The most significant differential gene expression in BRSV infected lung tissues was observed in the comparison of LL with LN; oxidative stress and cell damage was especially noticeable. Innate and adaptive immune functions were reduced in LL. As expected, combined treatment with FPI and Ibuprofen, when started early, made the most difference in gene expression patterns in comparison with placebo, especially in pathways related to the innate and adaptive immune response in both LL and LN. Ibuprofen, when used alone, negatively affected the antiviral response and caused higher virus loads as shown by increased viral shedding. In contrast, when used with FPI Ibuprofen enhanced the specific antiviral effect of FPI, due to its ability to reduce the damaging effect of prostanoids and oxidative stress.
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Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Infecciones por Virus Sincitial Respiratorio/genética , Virus Sincitial Respiratorio Bovino/genética , Animales , Antiinflamatorios no Esteroideos/farmacología , Antivirales/farmacocinética , Bovinos , Enfermedades de los Bovinos/inmunología , Inhibidores de la Ciclooxigenasa/farmacología , Expresión Génica/efectos de los fármacos , Expresión Génica/genética , Perfilación de la Expresión Génica/métodos , Ibuprofeno/farmacología , Pulmón/citología , Pulmón/patología , Pulmón/virología , Infecciones por Virus Sincitial Respiratorio/metabolismo , Virus Sincitial Respiratorio Bovino/patogenicidad , Transcriptoma/efectos de los fármacos , Transcriptoma/genética , Esparcimiento de Virus/efectos de los fármacosRESUMEN
Fluid-fluid interfacial reactions in porous materials are pertinent to many engineering applications such as fuel cells, catalyst design, subsurface energy recovery (enhanced oil recovery), and CO2 storage. They have been identified to control physicochemical properties such as interfacial rheology, multiphase flow, and reaction kinetics. In recent years, engineered waterflooding has been identified as an effective way to increase hydrocarbon recovery and solid-fluid interaction has been assessed as the key mechanism. However, in this study, we demonstrated that in the absence of solid-fluid interactions (in strong hydrophilic porous media), fluid-fluid interfacial reactions can significantly affect multiphase flow and thus lead to an increased hydrocarbon recovery during engineered carbonated waterflooding. We designed a microwaterflooding system to evaluate the interfacial reactions during two phase flow with engineered carbonated waters. Given that salinity controls the amount of dissolved CO2, we injected carbonated high salinity water and carbonated low salinity water to achieve different fluid-fluid reactions. We injected the carbonated water in a sandstone with 99.5% quartz under X-ray microcomputed tomography (µCT) scanning at a resolution of 3.43 µm per pixel. Image processing shows that carbonated low salinity waterflooding can recover 8% more oil than carbonated high salinity waterflooding, while the quartz-rich sandstone remains strongly hydrophilic in both samples. A gradual CT intensity distribution indicates an interfacial phase generation between carbonated brine and crude oil during carbonated waterflooding. Therefore, we attributed the additional hydrocarbon recoveries to the fluid-fluid interfacial reactions. To understand the effects of fluid-fluid reactions on interfacial properties, we performed molecular dynamics simulations to investigate the chemical species distribution at the interface, interfacial tension (IFT) changes, and CO2 diffusion. The MD simulation results revealed a layered structure of the interface, a lower CO2 diffusion coefficient in carbonated high salinity water, a lower IFT in carbonated low salinity water, a swelling hydrocarbon phase in carbonated low salinity water, and more CO2 accumulated at the interface between the hydrocarbon phase and carbonated low salinity water. This work provides a general and fundamental understanding of the influence of fluid-fluid interactions on the interfacial properties between carbonated water and the hydrocarbon interface.
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γδ T cells are a numerically significant subset of immune cells in ruminants, where they may comprise up to 70 % of all peripheral blood mononuclear cells (PBMCs) in young animals and 25 % in adults. These cells can be activated through traditional TCR-dependent mechanisms, or alternatively in a TCR-independent manner by pattern recognition receptors and have been shown to uptake antigen, as well as process and present it to αß T cells. We have identified a novel CD11b+ subset of γδ T cells in normal sheep peripheral blood. An increase in the frequency of these cells in sheep peripheral blood in response to immunization with an experimental recombinant subunit Rift Valley fever (RVF) vaccine was observed. However, injection of the vaccine adjuvant ISA-25VG alone without the recombinant RVF virus antigens demonstrated the same effect, pointing to an antigen-independent innate immune function of CD11b+ γδ T cells in response to the adjuvant. In vitro studies showed repeatable increases of CD11b-, CD14-, CD86-, CD40-, CD72-, and IFNγ- expressing γδ T cells in PBMCs after 24 h of incubation in the absence of a mitogen. Moreover, the majority of these myeloid-like γδ T cells were demonstrated to process exogenous antigen even in the absence of mitogen. ConA activation increased CD25- and MHCII- expression in γδ T cells, but not the myeloid associated receptors CD14 or CD11b or co-stimulatory molecules such as CD86 and CD40. Considering the role of CD11b and CD14 in the activation of innate immunity, we hypothesize that this subpopulation of sheep γδ T cells may function as innate antigen presenting and pro-inflammatory cells during immune responses. The results presented here also suggest that stress molecules and/or damage-associated molecular patterns may be involved in triggering antigen presenting and pro-inflammatory functions of γδ T cells, given their appearance in vitro in the absence of specific stimulation. Taken together, these data suggest that the early appearance of γδ T cells following adjuvant administration and their possible role in early activation of αß T cell subsets may non-specifically contribute to augmented innate immunity and may promote strong initiation of the adaptive immune response to vaccines in general.
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Linfocitos Intraepiteliales/inmunología , Fiebre del Valle del Rift/inmunología , Vacunas Virales/inmunología , Animales , Presentación de Antígeno , Antígenos de Diferenciación/biosíntesis , Antígeno CD11b/biosíntesis , Proliferación Celular , Células Cultivadas , Femenino , Inmunidad Innata , Inmunogenicidad Vacunal , Inmunofenotipificación , Subunidad alfa del Receptor de Interleucina-2/biosíntesis , Células Mieloides/inmunología , Fiebre del Valle del Rift/prevención & control , OvinosRESUMEN
HYPOTHESIS: The advanced low salinity aqueous formulations are yet to be validated as an injection fluid for enhanced oil recovery (EOR) from the carbonate reservoirs and CO2 geosequestration. Interaction of various ionic species present in the novel low salinity surfactant nanofluids with scCO2/CO2 saturated aqueous phase interface and at the interface of CO2 saturated aqueous phase/mixed wet (with CO2 and Decane) limestone surface at the conditions of low salinity at reservoir conditions are to yet to be understood. EXPERIMENTS: This study, carried out for the first time in low salinity at scCO2 loading conditions at 20 MPa pressure and 343 K temperature, comprises of wettability study of the limestone surface by aqueous phase contact angle measurements using ZrO2 nanoparticles (in the concentration range of 100-2000 mg/L) and 0.82 mM Hexadecyltrimethylammonium bromide (CTAB) surfactant. Molecular dynamics simulations results were used to understand the underlying mechanism of wettability alteration and interfacial tension (IFT) change. FINDINGS: This study reveals that a low dosage (100 mg/L) of ZrO2 nanoparticles forming ZrO2-CTAB nano-complexes helps in wettability alteration of the rock surface to more water-wetting state; certain ionic species augment this effect when used in appropriate concentration. Also, these nano-complexes helps in scCO2/CO2 saturated aqueous phase IFT reduction. This study can be used to design advanced low salinity injection fluids for water alternating gas injection for EOR and CO2 geosequestration projects.
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The design of cargo carriers with high biocompatibility, unique morphological characteristics, and capability of strong bonding of fluorescent dye is highly important for the development of a platform for smart imaging and diagnostics. In this paper, BODIPY-doped silica nanoparticles were prepared through a "one-pot" soft-template method using a sol-gel process. Several sol-gel precursors have been used in sol-gel synthesis in the presence of soft-template to obtain the silica-based materials with the most appropriate morphological features for the immobilization of BODIPY molecules. Obtained silica particles have been shown to be non-cytotoxic and can be effectively internalized into the cervical cancer cell line (HeLa). The described method of synthesis allows us to obtain silica-based carriers with an immobilized fluorescent dye that provide the possibility for real-time imaging and detection of these carriers.
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Compuestos de Boro/química , Boro/química , Dimetilaminas/química , Nanopartículas/administración & dosificación , Dióxido de Silicio/química , Neoplasias del Cuello Uterino/tratamiento farmacológico , Supervivencia Celular , Femenino , Células HeLa , Humanos , Nanopartículas/química , Transición de Fase , Neoplasias del Cuello Uterino/metabolismoRESUMEN
INTRODUCTION: Bovine respiratory syncytial virus (RSV) is a valid model for human RSV and an important bovine pathogen. Very early administration of ibuprofen and GS-561937, a fusion protein inhibitor (FPI), have separately been shown to decrease the severity of bovine RSV. Our aims were to determine how long after RSV inoculation ibuprofen and GS-561937 can be administered with clinical benefit and whether using both was better than monotherapy. MATERIALS AND METHODS: We conducted a blinded randomized placebo controlled trial of ibuprofen, GS-561937 (FPI), or combinations of the two initiated at 3 or 5 days after artificial infection with bovine RSV in 36 five to six-week-old Holstein calves (Bos taurus). We measured clinical scores, respiratory rate, and viral shedding daily for 10 days following inoculation. We estimated the average effect for each drug and compared treatment arms using mixed effects models. RESULTS: We found a significant decrease in clinical scores only in the combined treatment arms. This benefit was greater when treatment was initiated at 3 days rather than 5 days post infection with decreased clinical scores and lower respiratory rates at both time points. Ibuprofen alone started on day 3 increased, and FPI with ibuprofen started on day 3 decreased, viral shedding. CONCLUSION: Dual therapy with Ibuprofen and FPI, on average, decrease clinical severity of illness in a bovine model of RSV when started at 3 and 5 days after infection.
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Antiinflamatorios no Esteroideos/farmacología , Antivirales/farmacología , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Virus Sincitial Respiratorio Bovino/efectos de los fármacos , Animales , Bovinos , Modelos Animales de Enfermedad , Humanos , Ibuprofeno/farmacología , Pulmón/virología , Carga Viral/efectos de los fármacos , Replicación Viral/efectos de los fármacosRESUMEN
HYPOTHESIS: Low salinity surfactant nanofluids have recently shown promising characteristics in wettability alteration of the silicate-based rock representative substrate and interfacial tension reduction of oil/aqueous phase interface. Pore level understanding of the physical processes entailed in this new class of low salinity injection fluids in oil-phase saturated real rock porous media is required, which has not been conceived yet. EXPERIMENTS: Thus, we investigate the oil recovery performance and possible mechanisms of oil recovery by the injection of low salinity surfactant (SDBS, 1.435 mM) aqueous solutions (with 0%, 0.01% and 0.1% (by weight) ZrO2 nanoparticles) into the oil phase saturated Doddington sandstone miniature core plugs. The designed experiment involves core flooding with X-ray transparent core-holder developed in-house and analysis/processing of the acquired image data. FINDINGS: The injection of low salinity surfactant nanofluids with 0.01% ZrO2 nanoparticles leads to maximum oil phase recovery. The results suggest that the dominating mechanisms for oil recovery are wettability alteration, inherent interfacial tension reduction, and the effect of significant amount of microemulsions formation is rather trivial. Low salinity effect, even in combination with surfactant, caused fines migrations (not reported earlier), is found to be significantly mitigated using nanoparticles. This new class of fluids may significantly enhance oil recovery.