Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 135
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Lab Chip ; 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34821225

RESUMO

The behaviours of microparticles inside a sessile droplet actuated by surface acoustic waves (SAWs) were investigated, where the SAWs produced an acoustic streaming flow and imparted an acoustic radiation force on the microparticles. The Rayleigh waves formed by a comb-like interdigital transducer were made to propagate along the surface of a LiNbO3 substrate in order to allow the manipulation of microparticles in a label-free and non-contact manner. Polystyrene microparticles were first employed to describe the behaviours inside a sessile droplet. The influence of the volume of the sessile droplet on the behaviours of the microparticles was examined by changing the contact angle of the droplet. Next, cancer cells were suspended in a sessile droplet, and the influence of contact angle on the behaviours of the cancer cells was investigated. A long gelation time was afforded by using a PEGylated fibrin gel. A primary tumour was mimicked by patterning the cancer cells to be concentrated in the middle of the sessile droplet. The non-contact manipulation property of acoustic waves was indicated to be biocompatible and enabled a structure-free platform configuration. Three-dimensional aggregated culture models were observed to make the cancer cells display an elevated expression of E-cadherin. The efficacy of the anticancer drug tirapazamine increased in the aggregated cancer cells, attributed to the low levels of oxygen in this formation of cancer cells.

2.
Cell Rep ; 37(7): 110018, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34788612

RESUMO

Chronic injury to hepatocytes results in inflammation, steatohepatitis, fibrosis, and nonalcoholic fatty liver disease (NAFLD). The tetraspanin TM4SF5 is implicated in fibrosis and cancer. We investigate the role of TM4SF5 in communication between hepatocytes and macrophages (MΦs) and its possible influence on the inflammatory microenvironment that may lead to NAFLD. TM4SF5 induction in differentiated MΦs promotes glucose uptake, glycolysis, and glucose sensitivity, leading to M1-type MΦ activation. Activated M1-type MΦs secrete pro-inflammatory interleukin-6 (IL-6), which induces the secretion of CCL20 and CXCL10 from TM4SF5-positive hepatocytes. Although TM4SF5-dependent secretion of these chemokines enhances glycolysis in M0 MΦs, further chronic exposure reprograms MΦs for an increase in the proportion of M2-type MΦs in the population, which may support diet- and chemical-induced NAFLD progression. We suggest that TM4SF5 expression in MΦs and hepatocytes is critically involved in modulating the inflammatory environment during NAFLD progression.

3.
World J Gastrointest Surg ; 13(10): 1235-1244, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34754391

RESUMO

BACKGROUND: Neoadjuvant chemotherapy (NACT) and oesophagectomy is the standard of care for resectable oesophageal adenocarcinomas. Survival outcomes following resection have been improving over time while NACT remain largely unchanged. Indeed, a recent meta-analysis of randomized control trials did not demonstrate a survival benefit in adding NACT, raising the possibility that improved surgical techniques may be reducing the perceived effectiveness of NACT. AIM: To compare the effect of addition of NACT to a standardized surgery and lymphadenectomy on overall and disease-free survival in patients undergoing curative oesophagectomy for oesophageal adenocarcinoma. METHODS: Patient data were analysed from a prospectively maintained surgical survival database. Demographic, surgical, and survival outcomes were compared between groups according to treatment and nodal count. RESULTS: The data of 243 consecutive patients were identified. 79 patients were given NACT and 162 had surgery only. The NACT group were younger, and there was less frequent stage I adenocarcinoma. Overall survival was similar between NACT and surgery only groups (5YS: 48.7% vs 42.5%; P = 0.113), as was disease-free survival (5YS: 40.6% vs 39.9%; P = 0.635). There were ≥ 30 nodes removed in 46 patients, and < 30 in 197 patients, but were otherwise similar. There was improved survival in patients with ≥ 30 nodes removed than those with < 30 nodes (5YS: 64.4% vs 40.7%; P = 0.015), and a better disease-free survival that neared significance (5YS: 54.9% vs 36.6%; P = 0.078). CONCLUSION: NACT did not appear to affect overall or disease-free survival. However, an overall survival benefit was observed in patients with ≥ 30 lymph nodes removed, and a benefit in disease-free survival which was not significant.

4.
Phys Rev Lett ; 127(12): 126404, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34597093

RESUMO

Electron-phonon (e-ph) interactions are pervasive in condensed matter, governing phenomena such as transport, superconductivity, charge-density waves, polarons, and metal-insulator transitions. First-principles approaches enable accurate calculations of e-ph interactions in a wide range of solids. However, they remain an open challenge in correlated electron systems (CES), where density functional theory often fails to describe the ground state. Therefore reliable e-ph calculations remain out of reach for many transition metal oxides, high-temperature superconductors, Mott insulators, planetary materials, and multiferroics. Here we show first-principles calculations of e-ph interactions in CES, using the framework of Hubbard-corrected density functional theory (DFT+U) and its linear response extension (DFPT+U), which can describe the electronic structure and lattice dynamics of many CES. We showcase the accuracy of this approach for a prototypical Mott system, CoO, carrying out a detailed investigation of its e-ph interactions and electron spectral functions. While standard DFPT gives unphysically divergent and short-ranged e-ph interactions, DFPT+U is shown to remove the divergences and properly account for the long-range Fröhlich interaction, allowing us to model polaron effects in a Mott insulator. Our work establishes a broadly applicable and affordable approach for quantitative studies of e-ph interactions in CES, a novel theoretical tool to interpret experiments in this broad class of materials.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34605162

RESUMO

INTRODUCTION: Laryngopharyngeal reflux (LPR) and gastro-oesophageal reflux disease (GORD) result from the reflux of gastric contents. The post-reflux swallow-induced peristaltic wave (PSPW) is an oesophageal reflex that facilitates chemical clearance of gastric contents following reflux events. PSPW index is a novel parameter that has been validated in assessing the effectiveness of chemical clearance in GORD, but not in LPR. This study aimed to assess chemical clearance in LPR and GORD by measuring PSPW indices in a consecutive series of patients. METHODS: Reviewers blindly analysed off-therapy impedance-pH tracings from 187 patients clinically categorized as LPR (n = 105) or GORD (n = 82) by predominant symptom profile. Conventional impedance-pH measures and PSPW indices were analysed. RESULTS: Mean PSPW index in the LPR group was higher than in the GORD group (39.7% (±17.7%) vs. 20.6% (±13.4%); p < 0.001). Abnormally low PSPW index (<61%) was seen in 85 (81%) of the LPR group, and 80 (97.6%) of the GORD group (p < 0.001). Area under the ROC curve for PSPW index to diagnose LPR was 0.83 (95% CI: 0.767-0.889; p < 0.001). CONCLUSION: Post-reflux swallow-induced peristaltic wave was impaired in patients with LPR as well as oesophageal GORD, indicating an abnormality of chemical clearance following a reflux episode in both groups. PSPW index was more severely impaired in gastro-oesophageal reflux disease (GORD). The present study shows PSPW index is useful in the diagnosis of both LPR and GORD and exposes an abnormality of clearance of the oesophagus.

6.
Microorganisms ; 9(9)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34576698

RESUMO

Streptomyces spp. have been major contributors of novel natural products that are used in many application areas. We found that the nojirimycin (NJ) producer JCM 3382 has antimicrobial activity against Staphylococcus aureus via cellular degradation. Genome analysis revealed 30 biosynthetic gene clusters, including those responsible for producing antibiotics, including an azasugar NJ. In-depth MS/MS analysis confirmed the production of 1-deoxynojirimycin (DNJ) along with NJ. In addition, the production of tambromycins, setomimycin, and linearmycins was verified by spectroscopic analyses, including LC-MS and NMR. The distribution of the clusters of genes coding for antibiotics in 2061 Streptomyces genomes suggested potential producers of tambromycin, setomimycin, and linearmycin. For a DNJ gene cluster, homologs of gabT1 and gutB1 were commonly found; however, yktC1 was identified in only 112 genomes. The presence of several types of clusters suggests that different strains may produce different types of azasugars. Chemical-profile-inspired comparative genome analysis may facilitate a more accurate assessment of the biosynthetic potential to produce secondary metabolites.

7.
Microorganisms ; 9(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34576875

RESUMO

The dung beetle Copris tripartitus Waterhouse (Coleoptera: Scarabaeidae) is a coprophagous insect that lives in and feeds primarily on the feces of mammalian herbivores and is known to protect their offspring from the pathogen-rich environment by performing parental care for brood balls. Brood balls under continuous management by dung beetle are rarely contaminated by entomopathogenic fungi compared to abandoned brood balls. On the supposition that dung beetles may benefit from mutualistic bacteria that protect their offspring against fungal pathogens, we evaluated the antifungal activities of bacteria isolated from the dung beetle and brood ball. As a result, bacterial isolates, mainly streptomycetes, manifested potent and broad-spectrum antifungal activity against various fungi, including entomopathogens. Of the isolates, Streptomyces sp. AT67 exhibited pronounced antifungal activities. Culture-dependent and independent approaches show that this strain has occurred continuously in dung beetles that were collected over three years. Moreover, metabolic profiling and chemical investigation demonstrated that the strain produced an antifungal polyene macrocyclic lactam, sceliphrolactam, as a major product. Our findings imply that specific symbiotic bacteria of C. tripartitus are likely to contribute brood ball hygiene by inhibiting fungal parasites in the environment.

8.
Lab Chip ; 21(18): 3449-3457, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34342326

RESUMO

An efficient and accurate antibiotic susceptibility test (AST) is indispensable for measuring the antimicrobial resistance of pathogenic bacteria. A minimal inhibitory concentration (MIC) can be obtained without performing repeated dilutions of the antibiotic by forming a linear antibiotic concentration gradient in a microfluidic channel. We demonstrated a device designed to use travelling surface acoustic waves (TSAWs) to enable a rapid formation of an antibiotic gradient in a few seconds. The TSAWs produced by a focused interdigital transducer deposited on the surface of a piezoelectric (LiNbO3) substrate generated an acoustic streaming flow inside a microfluidic channel, which mixed confluent streams of antibiotics in a controlled fashion. The growth of bacteria exposed to the antibiotic gradient was determined by measuring the MIC, which was used as an indicator of the effectiveness of the AST. The concentration gradient produced using our device was linear, a feature that enhanced the reliability of measurements throughout the microchannel. Two ASTs, namely Pseudomonas aeruginosa against gentamicin and levofloxacin were chosen for the case of slowly proliferating bacteria, and one AST, namely Escherichia coli against gentamicin, were chosen for the rapidly proliferating case. Appropriate antibiotic doses for Pseudomonas aeruginosa and Escherichia coli were each obtained in an efficient manner.


Assuntos
Antibacterianos , Escherichia coli , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Reprodutibilidade dos Testes , Som
9.
Bioorg Med Chem Lett ; 49: 128312, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34375718

RESUMO

The neuroprotective activity of 2-heptyl-3-hydroxy-4(1H)-quinolone (compound 1) was evaluated using the neurotoxicity of glutamate in the HT22 cell line. Compound 1, known as a signal molecule of the bacterial quorum-sensing system, protects neuronal cells from glutamate-induced neurotoxicity by inhibiting cellular Ca2+ uptake and glutamate-triggered ROS accumulation. MAPK signaling pathway inhibition by compound 1 was evaluated by immunoblotting the phosphorylation status of the proteins. Furthermore, pro-apoptotic protein levels and AIF translocation to the nucleus were found to be reduced by compound 1. In conclusion, compound 1 showed neuroprotective effects by inhibiting apoptotic neuronal cell death.

10.
Dev Reprod ; 25(2): 83-91, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34386643

RESUMO

The present study was performed to investigate the effect of maternal hypothyroidism and puberty onset in female rat pups. To do this, we employed propylthiouracil (PTU) to prepare a hypothyroid rat model. Pregnant rats were treated with PTU (0.025%) in drinking water from gestational day 14 to postnatal day 21 of offspring. Comparison of general indices such as body and tissue weights and puberty indices such as vaginal opening (VO) and tissue histology between control and PTU-treated rats were conducted. There was no significant difference in the date of VO between control and PTU group. The body weights of the PTU group were significantly lower, only 36.8% of the control group (p<0.001). Although the absolute thyroid weight was not changed by PTU treatment, the relative weight increased significantly about 2.8 times (p<0.001), indicating that hypothyroidism was successfully induced. On the other hand, the absolute weights of the ovary and uterus were markedly decreased by PTU administration (p<0.001), and the relative weight was not significantly changed. The ovarian histology of PTU group revealed the advanced state of differentiation (i.e., presence of corpora lutea). Inversely, the uterine histology of PTU group showed underdeveloped structures compared those in control group. Taken together, the present study demonstrates that our maternal hypothyroidism model resulted in minimal effect on pubertal development symbolized by VO despite of huge retardation in somatic growth. More sophisticatedly designed hypothyroidism model will be helpful to achieve a better understanding of pubertal development and related disorders.

11.
Bioorg Chem ; 114: 105112, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34216894

RESUMO

The consumption of sprouts has been steadily increasing due to their being an excellent source of nutrition. It is known that the bioactive constituents of legumes can be increased after germination. In this study, the extract from Senna tora sprouts is shown to exhibit improved radical scavenging activities and better neuroprotective effects in HT22 hippocampal neuronal (HT22) and R28 retina precursor (R28) cells than those from seeds due to an increased content of phenolic constituents, especially compounds 1 and 3-6. A phytochemical investigation of S. tora sprouts resulted in the isolation of two new naphthopyrone glycosides (1-2) with 27 previously reported compounds. Their structures were determined via interpreting spectroscopic data. Compounds 1 and 3-6 were found to possess radical scavenging activities and neuroprotective effects against oxidative stress in both neuronal cells. Hence, Senna tora sprouts and their constituents may be developed as natural neuroprotective agents via antioxidative effects.

12.
Environ Sci Technol ; 55(16): 11388-11396, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34310128

RESUMO

Irreversible faradic reactions in reverse electrodialysis (RED) are an emerging concern for scale-up, reducing the overall performance of RED and producing environmentally harmful chemical species. Capacitive RED (CRED) has the potential to generate electricity without the necessity of irreversible faradic reactions. However, there is a critical knowledge gap in the fundamental understanding of the effects of operational stack voltages of CRED on irreversible faradic reactions and the performance of CRED. This study aims to develop an active control strategy to avoid irreversible faradic reactions and pH change in CRED, focusing on the effects of a stack voltage (0.9-5.0 V) on irreversible faradic reactions and power generation. Results show that increasing the initial output voltage of CRED by increasing a stack voltage has an insignificant impact on irreversible faradic reactions, regardless of the stack voltage applied, but a cutoff output voltage of CRED is mainly responsible for controlling irreversible faradic reactions. The CRED system with eliminating irreversible faradic reactions achieved a maximum power density (1.6 W m-2) from synthetic seawater (0.513 M NaCl) and freshwater (0.004 M NaCl). This work suggests that the control of irreversible faradic reactions in CRED can provide stable power generation using salinity gradients in large-scale operations.


Assuntos
Água Doce , Salinidade , Eletricidade , Fenômenos Físicos , Água do Mar
13.
J Nat Prod ; 84(7): 2020-2027, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34236881

RESUMO

The tropolone-bearing sesquiterpenes juniperone A (1) and norjuniperone A (2) were isolated from the folk medicinal plant Juniperus chinensis, and their structures were determined by a combination of spectroscopic and crystallographic methods. Photojuniperones A1 (3) and A2 (4), bearing bicyclo[3,2,0]heptadienones derived from tropolone, were photochemically produced and structurally identified by spectroscopic methods. Predicted by the machine learning-based assay, 1 significantly inhibited the action of tyrosinase. The new compounds also inhibited lipid accumulation and enhanced the extracellular glycerol excretion.

14.
Int J Chron Obstruct Pulmon Dis ; 16: 1497-1508, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113087

RESUMO

Purpose: The identification of blood biomarkers to diagnose acute exacerbation of chronic obstructive pulmonary disease (AECOPD) will have clinical utility. Here, we used a proteomics-based approach to identify biomarkers capable of identifying AECOPD. Patients and Methods: This prospective, single-center pilot study enrolled 12 patients who came to Asan Medical Center (South Korea) via the outpatient clinic or emergency department with symptoms of AECOPD and were follow-up in the outpatient clinic during convalescence between 2015 and 2017. Paired blood samples collected from each patient during the treatment naïve AECOPD and convalescence stages were analyzed. A sequential window acquisition of all theoretical fragmentation spectra-mass spectrometry (SWATH-MS)-based proteome analysis was performed and a subset of the data were verified by ELISA. Results: The SWATH-MS analysis identified 226 plasma proteins across all samples examined. The median coefficient of variation for triplicate technical replicates of each sample was 1.13 ± 1.38%, indicating high precision of the technique. Fold-change and paired t-test analyses revealed that 14 proteins were present at higher levels in the AECOPD samples than in the convalescence samples. A gene ontology analysis revealed that these proteins are involved in the acute-phase response. A total of 15 proteins were present at higher levels during the recovery (convalescence) stage than during the acute exacerbation phase, and gene ontology analysis revealed that these proteins are related to lipid metabolism and transport. Verification of the SWATH-MS data was performed using ELISAs for three proteins that were up-regulated in AECOPD, namely, LBP, ORM2, and SERPINA3. Among them, SERPINA3 (p = 0.005) was up-regulated significantly in AECOPD compared with the convalescence state. Conclusion: Potential plasma biomarkers of AECOPD were discovered using the SWATH-MS proteomics method, and functional molecular associations were investigated. SERPINA3 could be a promising diagnostic biomarker for the early identification and tracking of AECOPD.


Assuntos
Proteômica , Doença Pulmonar Obstrutiva Crônica , Biomarcadores , Progressão da Doença , Humanos , Projetos Piloto , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , República da Coreia
15.
Anal Chem ; 93(23): 8309-8317, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34075739

RESUMO

We propose an acoustofluidic method for the triseparation of proteins conjugated with aptamer-coated microparticles inside a microchannel. Traveling surface acoustic waves (TSAWs) produced from a slanted-finger interdigital transducer (SFIT) are used to separate the protein-loaded microparticles of different sizes via the TSAW-driven acoustic radiation force (ARF). The acoustofluidic device consists of an SFIT deposited onto a piezoelectric lithium niobate substrate and a polydimethylsiloxane (PDMS) microfluidic channel on top of the substrate. The TSAWs propagating on the substrate penetrate into the sample fluid flow, where the human protein-conjugated microparticles are suspended, inside the PDMS microchannel. The microparticles are subjected to the TSAW-driven ARF with varying magnitude depending on their size and thus flow along different streamlines, leading to triseparation of the proteins. In this work, we used two different-sized streptavidin-functionalized polystyrene (PS) microparticles to capture two kinds of aptamers (apt15 and aptD17.4), which were labeled with a respective biotin molecule at one end. The biotin ends of the aptamers were attached to the microparticles through streptavidin-biotin linkage, whereas the free ends of the aptamers were used to capture their target proteins of thrombin (th) and immunoglobulin E (IgE). The resultant PS-apt15-th and PS-aptD17.4-IgE complexes, as well as mCardinal2, were used for experimental demonstration of acoustofluidic triseparation of the human proteins. We achieved simultaneous separation of proteins of three kinds (th, IgE, and mCardinal2) for the first time via the TSAW-driven ARF in the proposed acoustofluidic device.


Assuntos
Acústica , Microfluídica , Proteínas/isolamento & purificação , Biotina , Humanos , Poliestirenos , Estreptavidina
16.
J Dig Dis ; 22(7): 419-424, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34042298

RESUMO

OBJECTIVES: Mean nocturnal baseline impedance (MNBI) shows promise in investigating reflux disease by reflecting esophageal mucosal integrity. This study aimed to measure MNBI by both conventional and simple methods in patients with laryngopharyngeal reflux (LPR) and gastroesophageal reflux disease (GERD) in order to evaluate the efficacy of the simple measurement method. METHODS: Altogether 187 patients were divided into LPR (n = 105) or GERD (n = 82) groups according to their predominant symptom profile, and underwent off-therapy impedance-pH monitoring. MNBI was measured by both the conventional and simple methods. The Bland-Altman plots were constructed to assess mean differences and to identify bias in the two measurement methods. RESULTS: For the two measurement methods, mean difference was (-89 ± 328) Ω in the distal esophagus, (-6 ± 653) Ω in the proximal esophagus, and (128 ± 577) Ω in the pharynx, respectively. There was a strong correlation between conventional and simple MNBI values, with  the coefficient of 0.940 in the distal esophagus, 0.463 in the proximal esophagus, and 0.712 in the pharynx (all P < 0.001). CONCLUSIONS: There was an excellent agreement between the conventional and simple methods of MNBI measurement, with no evidence of proportional bias. Conventional and simple MNBI values correlated excellently in the distal esophagus and moderately well in the proximal esophagus and pharynx. This study supports the use of the simple method of measuring MNBI to enhance diagnoses of reflux disease.


Assuntos
Impedância Elétrica , Monitoramento do pH Esofágico , Refluxo Gastroesofágico , Mucosa Esofágica/fisiopatologia , Monitoramento do pH Esofágico/métodos , Esôfago/fisiopatologia , Refluxo Gastroesofágico/diagnóstico , Humanos , Refluxo Laringofaríngeo/diagnóstico , Faringe/fisiopatologia
17.
Exp Mol Med ; 53(5): 986-992, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34035465

RESUMO

Emphysema, a pathological component of chronic obstructive pulmonary disease, causes irreversible damage to the lung. Previous studies have shown that Slit plays essential roles in cell proliferation, angiogenesis, and organ development. In this study, we evaluated the effect of Slit2 on the proliferation and migration of mouse lung epithelial cells and its role in regeneration in an emphysema lung mouse model. Here, we have shown that Slit2/Robo signaling contributes to the regeneration of lungs damaged by emphysema. Mouse epithelial lung cells treated with Slit2 exhibited increased proliferation and migration in vitro. Our results also showed that Slit2 administration improved alveolar regeneration in the emphysema mouse model in vivo. Furthermore, Slit2/Robo signaling increased the phosphorylation of ERK and Akt, which was mediated by Ras activity. These Slit2-mediated cellular signaling processes may be involved in the proliferation and migration of mouse lung epithelial cells and are also associated with the potential mechanism of lung regeneration. Our findings suggest that Slit2 administration may be beneficial for alveolar regeneration in lungs damaged by emphysema.

18.
J Photochem Photobiol B ; 218: 112184, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33848804

RESUMO

Tripterygium wilfordii Hook. f. is a traditional medicinal plant and has long been used in East Asia to treat many diseases. However, the extract and active components have never been investigated as potential photosensitizers for photodynamic treatment to kill pathogenic microorganisms. Here, the antimicrobial photodynamic treatment (APDT) effects of the extract, fractions, and compounds of T. wilfordii were evaluated in vitro and in vivo. Ethanolic extract (TWE) and the photosensitizer-enriched fraction (TW-F5) were prepared from dried T. wilfordii. Six active compounds were isolated from TW-F5 by semipreparative high-performance liquid chromatography, and their chemical structures were characterized through spectroscopic and spectrometric analysis. The singlet oxygen from extracts, fractions, and compounds was measured by using the imidazole-N,N-dimethyl-4-nitrosoaniline method. These extracts, fractions, and compounds were used as photosensitizers for the inactivation of bacteria and fungi by red light at 660 nm. The in vitro APDT effects were also evaluated in the model animal Caenorhabditis elegans. APDT with TWE showed effective antimicrobial activity against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and Candida albicans. TW-F5, consisting of six pheophorbide compounds, also showed strong APDT activity. The photosensitizers were taken up into the bacterial cells and induced intracellular ROS production by APDT. TWE and TW-F5 also induced a strong APDT effect in vitro against skin pathogens, including Staphylococcus epidermidis and Streptococcus pyogenes. We evaluated the APDT effects of TWE and TW-F5 in C. elegans infected with various pathogens and found that PDT effectively controlled pathogenic bacteria without strong side effects. APDT reversed the growth retardation of worms induced by pathogen infection and decreased the viable pathogenic bacterial numbers associated with C. elegans. Finally, APDT with TWE increased the survivability of C. elegans infected with S. pyogenes. In summary, TWE and TW-F5 were found to be effective antimicrobial photosensitizers in PDT.


Assuntos
Anti-Infecciosos/química , Caenorhabditis elegans/efeitos dos fármacos , Fármacos Fotossensibilizantes/química , Extratos Vegetais/química , Tripterygium/química , Animais , Anti-Infecciosos/farmacologia , Candida albicans/efeitos dos fármacos , Permeabilidade da Membrana Celular , Farmacorresistência Bacteriana , Humanos , Meticilina/farmacologia , Modelos Animais , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Oxigênio Singlete/química , Oxigênio Singlete/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis
19.
Lung ; 199(2): 139-145, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33751204

RESUMO

INTRODUCTION: Previously described methodologies for detecting laryngopharyngeal reflux (LPR) have limitations. Symptoms alone are non-diagnostic, and pH-impedance studies have poor sensitivity. Pulmonary micro-aspiration is under-recognised in LPR and gastro-esophageal reflux disease (GERD). The present study aimed to describe the results of a modified technique for scintigraphic reflux studies in two groups with severe reflux: those with typical reflux symptoms and those with laryngopharyngeal manifestations of reflux. METHODS: A prospective database of severely symptomatic, treatment-resistant reflux patients was grouped based upon predominant symptom profile of typical GERD or LPR. All patients underwent reflux scintigraphy. Results were obtained for early scintigraphic reflux contamination of the pharynx and proximal esophagus, and delayed contamination of the pharynx and lungs after 2 h. RESULTS: 187 patients were studied (82 GERD, 105 LPR). The LPR patients were predominantly female (70.5% vs. 56.1%; p = 0.042) and older than the GERD group (median age 60 years vs. 55.5 years; p = 0.002). Early scintigraphic reflux was seen at the pharynx in 89.2% (GERD 87.7%, LPR 90.4%; p = 0.133), and at the proximal esophagus in 89.7% (GERD 88.9%, LPR 90.4%; p = 0.147). Delayed contamination of the pharynx was seen in 95.2% (GERD 93.9%, LPR 96.2%; p = 0.468). Delayed pulmonary aspiration was seen in 46% (GERD 36.6%, LPR 53.3%; p = 0.023). CONCLUSION: Reflux scintigraphy demonstrated a high rate of reflux-related pulmonary aspiration. Contamination of the proximal esophagus and pharynx was observed frequently in both groups of severe disease. The likelihood of pulmonary aspiration and potential pulmonary disease needs to be entertained in severe GERD and LPR.


Assuntos
Aspiração Respiratória de Conteúdos Gástricos/diagnóstico por imagem , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Esôfago/diagnóstico por imagem , Esôfago/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Faringe/diagnóstico por imagem , Faringe/fisiopatologia , Estudos Prospectivos , Aspiração Respiratória de Conteúdos Gástricos/etiologia , Aspiração Respiratória de Conteúdos Gástricos/fisiopatologia , Avaliação de Sintomas , Adulto Jovem
20.
Sci Total Environ ; 773: 145531, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33582332

RESUMO

We investigated the changes in the size distribution, coating thickness, and mass absorption cross-section (MAC) of black carbon (BC) with aging and estimated the light absorption enhancement (Eabs) in the Asian outflow from airborne in-situ measurements during 2016 KORUS-AQ campaign. The BC number concentration decreased, but mass mean diameter increased with increasing altitude in the West Coast (WC) and Seoul Metropolitan Area (SMA), reflecting the contrast between freshly emitted BC-containing particles at the surface and more aged aerosol associated with aggregation during vertical mixing and transport. Contradistinctively, BC number and mass size distributions were relatively invariant with altitude over the Yellow Sea (YS) because sufficiently aged BC from eastern China were horizontally transported to all altitudes over the YS, and there are no significant sources at the surface. The averaged inferred MAC of refractory BC in three regions reflecting differences in their size distributions increased to 9.8 ± 1.0 m2 g-1 (YS), 9.3 ± 0.9 m2 g-1 (WC), and 8.2 ± 0.9 m2 g-1 (SMA) as BC coating thickness increased from 20 nm to 120 nm. The absorption coefficient of BC calculated from the coating thickness and MAC were highly correlated with the filter-based absorption measurements with the slope of 1.16 and R2 of 0.96 at 550 nm, revealing that the thickly coated BC had a large MAC and absorption coefficient. The Eabs due to the inferred coatings was estimated as 1.0-1.6, which was about 30% lower than those from climate models and laboratory experiments, suggesting that the increase in the BC absorption by the coatings in the Asian outflow is not as large as calculated in the previous studies. Organics contributed to the largest Eabs accounting for 69% (YS), 61% (WC), and 64% (SMA). This implies that organics are largely responsible for the lensing effect of BC rather than sulfates in the Asian outflow.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...