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1.
J Am Chem Soc ; 146(28): 19489-19498, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38975622

RESUMO

High oxidation state metal cations in the form of oxides, oxoanions, or oxoperoxoanions have diverse roles in carbon dioxide removal (direct air capture and point source). Features include providing basic oxygens for chemisorption reactions, direct binding of carbonate, and catalyzing low-temperature CO2 release to regenerate capture media. Moreover, metal oxides and aqueous metal-oxo species are stable in harsh, point-source conditions. Here, we demonstrate aqueous niobium polyoxometalate (POM) carbon capture ability, specifically [Nb6O19]8-, Nb6. Upon exposure of aqueous Nb6 to CO2, Nb6 fragments and binds chemisorbed carbonate, evidenced by crystallization of Nb-carbonate POMs including [Nb22O53(CO3)16]28-and [Nb10O25(CO3)6]12-. While Rb/Cs+ counter cations yield crystal structures to understand the chemisorption processes, K+ counter cations enable higher capture efficiency (based on CO3/Nb ratio), determined by CHN analysis and thermogravimetry-mass spectrometry of the isolated solids. Sum frequency generation spectroscopy also showed higher carbon capture efficiency of the K-Nb6 solutions at the air-water interface, while small-angle X-ray scattering (SAXS) provided insights into the role of the alkalis in influencing these processes. Tetramethylammonium counter cations, like K+, demonstrate high efficiency of carbonate chemisorption at the interface, but SAXS and Raman of the bulk showed a predominance of a Nb24-POM (HxNb24O72, x ∼ 9) that does not bind carbonate. Control experiments show that carbonate detected at the interface is Nb-bound, and the Nb-carbonate species are stabilized by alkalis, demonstrating their supporting role in aqueous Nb-POM CO2 chemisorption. Of fundamental importance, this study presents rare examples of directing POM speciation with a gas, instead of liquid phase acid or base.

2.
Int J Biol Macromol ; 273(Pt 2): 132955, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38852733

RESUMO

In this study, 4-sulfo-1,8-naphthalimide calixarene of derivatives were prepared (3 and 4) then transparent biofilms of the Ag salts of these compounds were formed in the presence of hyaluronic acid (HA), and antimicrobial properties were investigated. In chemosensor studies, the sensing ability behavior of 3 and 4 towards some cations and anions was investigated by fluorescence spectroscopy. It was observed that the prepared chemosensors show selectivity towards Hg(II) and Cr(VI). Ligand-ion interaction occurs according to the photo-induced electron transfer (PET) mechanism. The stoichiometric ratio was calculated by using Stern-Volmer plot method and binding constant Ksv values were found as 5.2 × 107 M-1 and 5.5 × 107 M-1 for 3-Hg(II) and 4-Hg(II) complexes, respectively and 4.0 × 107 M-1 and 4.3 × 107 M-1 for 3-Cr(VI) and 4-Cr(VI) complexes. The detection limits of the complexes of 3-Hg(II) and 4-Hg(II) are 6.35 × 10-12and 6.81 × 10-12, while those of 3-Cr(VI) and 4-Cr(VI) are 1.41 × 10- 11and 8.37 × 10-12, respectively. As a result of the antimicrobial test performed with these compounds, it was observed that the most effective material was HA-3Ag, which showed a significant antibacterial effect against Sarcina lutea (S. lutea) at a minimum inhibitory concentration (MIC) value of 0.097 mg/mL.


Assuntos
Biofilmes , Calixarenos , Ácido Hialurônico , Mercúrio , Naftalimidas , Calixarenos/química , Calixarenos/farmacologia , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Biofilmes/efeitos dos fármacos , Naftalimidas/química , Naftalimidas/farmacologia , Mercúrio/química , Cromo/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana , Espectrometria de Fluorescência , Antibacterianos/farmacologia , Antibacterianos/química , Fenóis/química , Fenóis/farmacologia , Fluorescência
3.
RSC Adv ; 14(11): 7582-7591, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38481608

RESUMO

Graphene oxide (GO) is a promising material for separations. Nanoscale GO thin films at the air/water interface are excellent experimental models to understand molecular-scale interactions of ions and water with GO. However, the characteristics of GO, such as functional groups and flake size, also affect the thin film properties making it difficult to make systematic studies with GO thin films. This paper reports a simple, reliable, and quick method of preparing ultra-thin GO films, irrespective of their origin, and demonstrates the new opportunities possible with the utilization of this method. The total amount of GO used to form the thin film is significantly less compared to previous examples in the literature, minimizing the dissolved GO in the subphase. X-ray reflectivity (XR) studies show that the majority of the GO film has 1.5 nm thickness over a macroscopic area (∼100 cm2) with very small roughness. Sum frequency generation (SFG) spectroscopy measurements show that H2O and D2O interact differently with GO films, a property that was not observed before. SFG data show that functional groups vary significantly between different commercially available GO samples. The differences are also characterized with XR at high resolution. X-ray fluorescence near total reflection (XFNTR) measurements show that these differences strongly affect ion adsorption and interfacial water behavior near GO, which are vital properties in separation applications. The results pave the way for future studies to elucidate the complex separation mechanisms with GO.

4.
J Chem Phys ; 160(8)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38415831

RESUMO

Graphene oxide (GO) is a two-dimensional, mechanically strong, and chemically tunable material for separations. Elucidating GO-ion-water interactions at the molecular scale is highly important for predictive understanding of separation systems. However, direct observations of the nanometer region by GO surfaces under operando conditions are not trivial. Therefore, thin films of GO at the air/water interface can be used as model systems. With this approach, we study the effects of alkali metal ions on water organization near graphene oxide films at the air/water interface using vibrational sum frequency generation (SFG) spectroscopy. We also use an arachidic acid Langmuir monolayer as a benchmark for a pure carboxylic acid surface. Theoretical modeling of the concentration-dependent sum frequency signal from graphene oxide and arachidic acid surfaces reveals that the adsorption of monovalent ions is mainly controlled by the carboxylic acid groups on graphene oxide. An in-depth analysis of sum frequency spectra reveals at least three distinct water populations with different hydrogen bonding strengths. The origin of each population can be identified from concentration dependent variations of their SFG signal. Interestingly, an interfacial water structure seemed mostly insensitive to the character of the alkali cation, in contrast to similar studies conducted at the silica/water interface. However, we observed an ion-specific effect with lithium, whose strong hydration prevented direct interactions with the graphene oxide film.

5.
Turk Patoloji Derg ; 40(1): 69-73, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37350642

RESUMO

Digital papillary adenocarcinoma (DPA) is a rare malignant eccrine tumor. A 62-year-old female presented with a subcutaneous nodular 1.5cm-mass in the thumb. Macroscopically, a poorly circumscribed mass containing cystic and solid components was observed. Microscopically, epithelial neoplasm consisting of tubular-cystic structures with back-to-back arrangements was observed. The lining epithelium was composed of cuboidal/columnar cells with mild atypia, with micropapillary extensions. Immunohistochemistry revealed double-layered neoplastic epithelium containing two different types of cells: basaloid/myoepithelial and luminal. We recommend two out of vimentin, HMWCK, and D2-40 for myoepithelial/basaloid cells, also CK7 and EMA for luminal/columnar cells. As the tumor had infiltrated the surgical margins, the patient underwent axillary sentinel lymph node (SLN) dissection and re-excision with Mohs micrographic surgery (MMS). Two additional MMS stages were required due to suspicious surgical margin positivity in the frozen sections. The operation was continued despite the risk of loss of function. Upon examination of the permanent sections, we observed no tumors in the suspected positive foci. Additionally, no tumor was found in the surgical margins. No metastasis was detected in the sentinel lymph node. We have reached 300 reported cases of DPA in the literature. We discussed the histopathological and intraoperative diagnostic pitfalls of DPA with a literature review and our experience.


Assuntos
Adenocarcinoma de Células Claras , Adenocarcinoma Papilar , Carcinoma , Feminino , Humanos , Pessoa de Meia-Idade , Margens de Excisão , Adenocarcinoma Papilar/cirurgia , Adenocarcinoma Papilar/patologia , Células Epiteliais/patologia
6.
Langmuir ; 39(49): 17570-17580, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37917551

RESUMO

Chemical separations play a vital role in refinery and reprocessing of critical materials, such as platinum group metals, rare earths, and actinides. The choice of separation system─whether it is liquid-liquid extraction (LLE), sorbents, or membranes─depends on specific needs and applications. In almost all separation processes, the desired metal ions adsorb or transfer across an aqueous interface, such as the solid/liquid interface in sorbents or oil/water interfaces in LLE. Despite these separation technologies being extensively used for decades, our understanding of the molecular-scale mechanisms governing ion adsorption and transport at interfaces remains limited. This knowledge gap presents a significant challenge in meeting the increasing demands for these critical materials due to their growing use in advanced technologies. Fortunately, recent advancements in surface-specific experimental and computational techniques offer promising avenues to bridge this gap and facilitate the development of next-generation separation systems. Interestingly, unanswered questions regarding interfacial phenomena in chemical separations hold great relevance to various fields, including energy storage, geochemistry, and atmospheric chemistry. Therefore, the model interfacial systems developed for studying chemical separations, such as amphiphilic molecules assembled at a solid/water, air/water, or oil/water interface, may have far-reaching implications, extending beyond separations and opening doors to addressing a wide range of scientific inquiries. This perspective discusses recent interfacial studies elucidating amphiphile-ion interactions in chemical separations of metal ions. These studies provide direct, molecular-scale information about solute and solvent behavior at aqueous interfaces, including multivalent and complex ions in highly concentrated solutions, which play key roles in LLE of critical materials.

7.
Nanoscale ; 15(35): 14679, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37671721

RESUMO

Correction for 'Ion and water adsorption to graphene and graphene oxide surfaces' by Amanda J. Carr, et al., Nanoscale, 2023, https://doi.org/10.1039/d3nr02452k.

8.
Ann Ital Chir ; 93: 316-321, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37530065

RESUMO

AIM - Anastomotic leakage is among the most common complications following gastrointestinal surgery. MATERIAL AND METHODS - This study aimed to determine the effects of stem cells and platelet-rich fibrin (PRF) on anastomotic healing. The study included 60 rats that were randomly divided into 3 groups, each with 2 subgroups. The study included the control group (no treatment post anastomosis), the PRF group (PRF administered following anastomosis), and the PRF + stem cell group (PRF + stem cells administered following anastomosis). Anastomosis was performed at the descending colon in all groups. Anastomosis bursting pressure was determined, and histopathological and angiographic examination were performed on postoperative D 7. RESULTS - Intraabdominal adhesion was significantly more common in the control group. Anastomosis bursting pressure was significantly higher and angiogenesis was significantly more common in the PRF + stem cell group (P < 0.005). Based on histopathologic examination, vascular proliferation and inflammation were significantly more common in the PRF + stem cell group than in the control group (P < 0.005). CONCLUSION : In cases of risky gastrointestinal system anastomosis, PRF + stem cells might reduce the incidence of anastomotic healing. KEY WORDS: Anastomosis, Platelet-rich fibrin, Stem cell, Wound healing.


Assuntos
Fibrina Rica em Plaquetas , Ratos , Animais , Anastomose Cirúrgica , Fístula Anastomótica/prevenção & controle , Cicatrização , Células-Tronco
9.
Nanoscale ; 15(35): 14319-14337, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37561081

RESUMO

Graphene and graphene oxide (GO) are two particularly promising nanomaterials for a range of applications including energy storage, catalysis, and separations. Understanding the nanoscale interactions between ions and water near graphene and GO surfaces is critical for advancing our fundamental knowledge of these systems and downstream application success. This minireview highlights the necessity of using surface-specific experimental probes and computational techniques to fully characterize these interfaces, including the nanomaterial, surrounding water, and any adsorbed ions, if present. Key experimental and simulation studies considering water and ion structures near both graphene and GO are discussed. The major findings are: water forms 1-3 hydration layers near graphene; ions adsorb electrostatically to graphene under an applied potential; the chemical and physical properties of GO vary considerably depending on the synthesis route; and these variations influence water and ion adsorption to GO. Lastly, we offer outlooks and perspectives for these research areas.

10.
Turk J Med Sci ; 53(3): 760-752, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37476909

RESUMO

BACKGROUND: Hydrochlorothiazide (HCTZ) possesses well-described photosensitizing properties, and a causal association with nonmelanoma skin cancer (NMSC) was recently shown. However, previous studies have not shown whether HCTZ use is associated with the risk of recurrence of basal cell carcinoma (BCC) or squamous cell carcinoma (SCC). This study aims to investigate the association between HCTZ use and recurrence in patients with NMSC. METHODS: We identified cases with NMSC from our hospital archives during the period between 2013 and 2019. Patients were divided into groups according to the pathological diagnosis, HCTZ use, and recurrence. Multivariable analysis was performed to determine factors associated with recurrence in BCC and SCC. RESULTS: Recurrences of BCC were significantly higher in HCTZ users with ORs of 4.839221 (95% confidence interval [CI], 1.22-19.12).In HCTZ users, NMSC cases were associated with increased age (p < 0.001 for both BCC and SCC). BCC recurrences were statistically significant with age, longer follow-up, and positive margins after excision in HCTZ users (p = 0.048, 0.020, and, 0.003, respectively). SCC recurrences were not significantly associated with HCTZ use. DISCUSSION: HCTZ use is significantly associated with BCC recurrences. Especially in the elderly population, cases with a positive margin should be followed closely.


Assuntos
Carcinoma Basocelular , Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Idoso , Estudos Retrospectivos , Hidroclorotiazida/uso terapêutico , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Recidiva
11.
Anal Chem ; 95(21): 8206-8213, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37195018

RESUMO

Electrochemical approaches provide unique means to fabricate thin films of metal-organic frameworks (MOFs). However, the kinetics of electrochemical MOF deposition has not been quantitatively investigated so far. In this study, we report the first in situ measurements of electrochemical MOF growth using transmission synchrotron X-ray scattering. Electrochemical cells based on poly(lactic acid) with two windows were fabricated using fused-deposition modeling. The resulting three-dimensional (3D)-printed cells, the surface of which was coated with paraffin wax to prevent solvent percolation through the polymer material, were used to monitor the cathodic growth of zeolitic imidazolate framework-8 (ZIF-8) on graphite in a methanol solution containing ZnCl2 and 2-methylimidazole (Hmim) at different cathodic potentials. The resulting time-resolved X-ray diffraction data showed a gradual increase in crystal size with negligible changes in crystal orientation during the cathodic ZIF-8 deposition. More importantly, the time-resolved data provided a means to quantitatively assess the kinetics of the cathodic ZIF-8 growth using the Gualtieri model, revealing that the cathodic potential and Hmim concentration affected crystal growth kinetics but not nucleation kinetics. These ZIF-8 samples exhibited changes in X-ray diffraction patterns after being washed with methanol and dried in air, indicating that in situ measurements are essential to investigate mechanisms behind MOF electrodeposition.

12.
Environ Res ; 231(Pt 1): 116089, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37172678

RESUMO

Seed priming is an effective and novel technique and the use of eco-friendly biological agents improves the physiological functioning in the vegetative stage of plants. This procedure ensures productivity and acquired stress resilience in plants against adverse conditions without contaminating the environment. Though the mechanisms of bio-priming-triggered alterations have been widely explained under induvial stress conditions, the interaction of combined stress conditions on the defense system and the functionality of photosynthetic apparatus in the vegetative stage after the inoculation to seeds has not been fully elucidated. After Bacillus pumilus inoculation to wheat seeds (Triticum aestivum), three-week-old plants were hydroponically exposed to the alone and combination of salt (100 mM NaCl) and 200 µM sodium arsenate (Na2HAsO4·7H2O, As) for 72 h. Salinity and As pollutant resulted in a decline in growth, water content, gas exchange parameters, fluorescence kinetics and performance of photosystem II (PSII). On the other hand, the seed inoculation against stress provided the alleviation of relative growth rate (RGR), relative water content (RWC) and chlorophyll fluorescence. Since there was no effective antioxidant capacity, As and/or salinity caused the induction of H2O2 accumulation and thiobarbituric acid reactive substances content (TBARS) in wheat . The inoculated seedlings had a high activity of superoxide dismutase (SOD) under stress. B. pumilis decreased the NaCl-induced toxic H2O2 levels by increasing peroxidase (POX) and enzymes/non-enzymes related to ascorbate-glutathione (AsA-GSH) cycle. In the presence of As exposure, the inoculated plants exhibited an induction in CAT activity. On the other hand, for H2O2 scavenging, the improvement in the AsA-GSH cycle was observed in bacterium priming plants plus the combined stress treatment. Since B. pumilus inoculation reduced H2O2 levels against all stress treatments, lipid peroxidation subsequently decreased in wheat leaves. The findings obtained from our study explained that the seed inoculation with B. pumilus provided an activation in the defense system and protection in growth, water status, and gas exchange regulation in wheat plants against the combination of salt and As.


Assuntos
Arsênio , Bacillus pumilus , Antioxidantes/farmacologia , Triticum , Cloreto de Sódio/toxicidade , Arsênio/farmacologia , Água , Peróxido de Hidrogênio , Fluorescência , Cinética , Clorofila/farmacologia
13.
J Phys Chem Lett ; 14(15): 3685-3690, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37036360

RESUMO

We study the adsorption of trivalent neodymium on floating arachidic acid films at the air-water interface by two complementary surface specific probes, sum frequency generation spectroscopy and X-ray fluorescence near total reflection. In the absence of background ions, neodymium ions compensate for the surface charge of the arachidic acid film at a bulk concentration of 50 µM without any charge reversal. Increasing the bulk concentration to 1 mM does not change the neodymium surface coverage but affects the interfacial water structure significantly. In the presence of a high concentration of NaCl, there is overcharging at 1 mM Nd3+, i.e., 30% more Nd3+ than needed to compensate for the surface charge. These results show that the total coverage of neodymium ions is not enough to describe the complete picture at the interface, and interfacial water and ion coverage needs to be considered together to understand more complex ion adsorption and transport processes.

14.
Int J Biol Macromol ; 240: 124426, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37060971

RESUMO

It is crucial to detect toxic chromium ions quickly, reliably, sensitively and at low concentrations. In recent years, fluorescence-based methods have been developed for the rapid detection and determination of toxic ions such as chromium. In present work, we focused on the development of a cellulose-based fluorescent probe (Cel-Nap) for the determination of Cr(VI). The fluorescent probe bearing the 1,8-naphthalimide group displayed a low LOD of 1.07 µM for Cr(VI) in the working range of 0.33 × 10-5-3.22 × 10-5 M. The fluorescence and antibacterial properties of UiO-66-Cel-Nap and ZIF-8-Cel-Nap materials prepared by encapsulating Cel-Nap with 2 different MOF types (UiO-66 and ZIF-8) were investigated. While it was found that ZIF-8-based materials had better antimicrobial properties compared to those of UiO-66, it was determined that materials containing Ag+ were more effective against microbial than those containing AgNPs. It was found that the most effective material was ZIF-8-Cel-Nap-Ag+ and it had a significant antibacterial effect against E. coli at a MIC value of 0.0024 mg/mL.


Assuntos
Anti-Infecciosos , Compostos Organometálicos , Corantes Fluorescentes , Celulose , Escherichia coli , Anti-Infecciosos/farmacologia , Cromo , Antibacterianos/farmacologia , Íons
15.
Minerva Dent Oral Sci ; 72(4): 161-167, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36951010

RESUMO

BACKGROUND: Several types of suture materials are available for oral surgery. However, the most used non-resorbable suture in oral surgery is 3/0 silk. The aim of the present study was to compare the effectiveness of knotless/barbed sutures with silk sutures during the postoperative period after the third molar surgery in terms of clinical and microbiological parameters. METHODS: The study comprised 38 patients who underwent surgical extraction of a mandibular impacted third molar. The patients were divided into two groups. The mucoperiosteal flap was closed using 3/0 knotless/barbed sutures for the test group and 3/0 silk sutures for the control group. The duration of suturing was recorded during surgery. Pain level, postoperative edema, and trismus were measured at 3 and 7 days after surgery. The status of plaque formation on the sutures was scored using the Plaque Index at 3 and 7 days after the surgery. At 7 days, the suture materials were removed and submitted to the laboratory for microbiological analysis. The level of pain during suture removal was also recorded by a Visual Analog Scale. RESULTS: The duration of suturing in the barbed sutures group was found significantly lower than in silk sutures (P<0.05). There was no significant difference between the suture types in terms of trismus and edema at 3 and 7 days after surgery (P>0.05). On the third day after surgery and during suture, removal pain scores were statistically significantly lower in the barbed suture group than in the silk suture group (P<0.05). The Plaque Index values of the barbed sutures were statistically significantly lower than that of the silk sutures at 3 and 7 days after surgery (P<0.05). Aerobic, anaerobic, and aerobic/anaerobic mean colony forming units (CFUs) were statistically significantly lower in the barbed suture group than in the silk suture group (P<0.05). CONCLUSIONS: Barbed sutures increase the ease of operation and patient comfort with less postoperative pain than silk sutures. Additionally, less plaque accumulation and lower bacterial colonization were found on the barbed/knotless sutures than on the silk sutures.


Assuntos
Dente Impactado , Trismo , Humanos , Trismo/etiologia , Trismo/cirurgia , Dente Serotino/cirurgia , Técnicas de Sutura/efeitos adversos , Suturas/efeitos adversos , Dente Impactado/cirurgia , Seda , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/cirurgia , Edema/etiologia , Edema/cirurgia
16.
Balkan Med J ; 40(2): 111-116, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36715054

RESUMO

Background: High-flow nasal cannula therapy has been shown to be useful in the treatment of patients with acute respiratory failure caused by severe acute respiratory syndrome-coronavirus disease-2. The ROX index can help predict the success of high-flow nasal cannula in coronavirus disease-19-related acute respiratory failure. However, the timing of ROX- index assessment is still unclear to protect the patients from complications due to early or delayed intubation. Aims: To evaluate the relation between ROX index patterns within the first 48 hours of the therapy and high-flow nasal cannula success rates. The secondary aim was to determine other possible predictors of high-flow nasal cannula failure. Study design: A cross-sectional study. Methods: Patients admitted to the intensive care unit between April 2020 and January 2022 with coronavirus disease-19-related acute respiratory failure and treated with high-flow nasal cannula were included in the study. Patients' demographics, clinical characteristics and laboratory findings at intensive care unit admission; ROX indices at initiation, 2nd, 8th, 12th, 24th and 48th hours of high-flow nasal cannula; and outcomes were recorded. Results: In the study period, 69th patients were managed with high-flow nasal cannula for at least 2 hours. While 24 patients (34.7%) were successfully weaned from high-flow nasal cannula, 45 (65.3%) patients failed. Overall mortality at day 28 was 44.9%. ROX indices were lower in the high-flow nasal cannula failure group through the 12th, 24th, and 48th hours of the therapy, no significant change was observed (P = 0.33). While an overall increase in ROX index patterns were detected in patients weaned from high-flow nasal cannula (P = 0.002). Pairwise analyses revealed that ROX indexes remain stable during the first 8th hours in both groups, then improved to 12th hours of the therapy in successfully high-flow nasal cannula-weaned patients. Conclusion: Dynamic assessments of the ROX indexes could be more suggestive rather than a point assessment to identify patients who would benefit from the high-flow nasal cannula or deteriorate in coronavirus disease-19 related acute respiratory failure.


Assuntos
COVID-19 , Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Humanos , Cânula/efeitos adversos , COVID-19/complicações , COVID-19/terapia , Oxigenoterapia , Estudos Transversais , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Unidades de Terapia Intensiva , Síndrome do Desconforto Respiratório/terapia , SARS-CoV-2
17.
Exp Clin Transplant ; 21(1): 47-51, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36656122

RESUMO

OBJECTIVES: Some of the most common problems after kidney transplant are urologic complications, including ureterocystoanastomosis leakage and stenosis with the development of severe renal graft complications. Isolated plasma contains active substances that cause the activation of various growth factors for the processes of tissue repair or regeneration, has an anti- inflammatory effect, activates angiogenesis, and reduces the risk of infectious complications. Platelet-rich plasma is actively used to stimulate bone regeneration, heal wounds and ulcers on the skin, enhance reconstruction of the larynx and trachea, and ameliorate urethral damage, among other uses. This study was developed to evaluate the positive effect of platelet-rich plasma on the healing process of an anastomotic wound in a model of ureterocystoanas-tomosis in rats. MATERIAL AND METHODS: We randomized 14 Wistar albino male rats into 2 groups: group 1 included 7 rats that received platelet-rich plasma after ureterocystostomy; group 2 was the control group and included 7 rats that underwent ureterocystostomy without platelet-rich plasma. On postoperative day 7, all animals were euthanized, and the anastomosis area was resected for determination of the tissue hydroxyproline levels and histopathology examination. RESULTS: Tissue hydroxyproline levels were 767 ± 62.9 µg/g in group 1 and 256 ± 28.0 µg/g in group 2. Tissue hydroxyproline levels were significantly higher in group 1 compared with group 2 (P < .05). There were no significant differences in epithelial damage, acute inflammation, or fibrosis between the tissue samples of both groups. CONCLUSIONS: The results of this study show that the use of platelet-rich plasma during ureterocystostomy produces a positive effect. Our further research will be devoted to the use of autologous platelet-rich plasma in ureterocystostomy in big models.


Assuntos
Plasma Rico em Plaquetas , Cicatrização , Ratos , Animais , Ratos Wistar , Hidroxiprolina , Pele , Plasma Rico em Plaquetas/metabolismo
19.
Sci Rep ; 12(1): 21443, 2022 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-36509873

RESUMO

Navigation is one of the most fundamental skills of animals. During spatial navigation, grid cells in the medial entorhinal cortex process speed and direction of the animal to map the environment. Hippocampal place cells, in turn, encode place using sensory signals and reduce the accumulated error of grid cells for path integration. Although both cell types are part of the path integration system, the dynamic relationship between place and grid cells and the error reduction mechanism is yet to be understood. We implemented a realistic model of grid cells based on a continuous attractor model. The grid cell model was coupled to a place cell model to address their dynamic relationship during a simulated animal's exploration of a square arena. The grid cell model processed the animal's velocity and place field information from place cells. Place cells incorporated salient visual features and proximity information with input from grid cells to define their place fields. Grid cells had similar spatial phases but a diversity of spacings and orientations. To determine the role of place cells in error reduction for path integration, the animal's position estimates were decoded from grid cell activities with and without the place field input. We found that the accumulated error was reduced as place fields emerged during the exploration. Place fields closer to the animal's current location contributed more to the error reduction than remote place fields. Place cells' fields encoding space could function as spatial anchoring signals for precise path integration by grid cells.


Assuntos
Células de Grade , Células de Lugar , Animais , Modelos Neurológicos , Córtex Entorrinal , Orientação , Hipocampo , Potenciais de Ação , Percepção Espacial
20.
ACS Appl Mater Interfaces ; 14(51): 57133-57143, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36533427

RESUMO

Graphene oxide (GO) membranes are excellent candidates for a range of separation applications, including rare earth segregation and radionuclide decontamination. Understanding nanoscale water and ion behavior near interfacial GO is critical for groundbreaking membrane advances, including improved selectivity and permeability. We experimentally examine the impact of solution conditions on water and lanthanide interactions with interfacial GO films and connect these results to GO membrane performance. The investigation of the confined films at the air-water interface with a combination of surface-specific spectroscopy and X-ray scattering techniques allows us to understand water and ion behaviors separately. Sum frequency generation spectroscopy reveals a dramatic change in interfacial water organization because of graphene oxide film deprotonation. Interfacial X-ray fluorescence measurements show a 17× increase in adsorbed lanthanide to the GO film from subphase pH 3 to pH 9. Liquid surface X-ray reflectivity data show an additional 2.7 e- per Å2 for GO films at pH 9 versus pH 3 as well. These results are connected to GO membrane performance, which show increased selectivity and decreased flux for membranes filtering pH 9 solutions. We posit insoluble lanthanide hydroxides form at higher pHs. Taken together, these results highlight the importance of interfacial experiments on model GO systems.

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