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The 5-fluoroalkyl-1,2,3-triazoles, serving as a pivotal element in medicinal chemistry, hold substantial research significance. In this work, we developed a furan dearomatization reaction for the synthesis of various 5-fluoroalkyl-1,2,3-triazoles, which contains -CF3, -CF2H, -CF2CF3, -CF2CF2CF3, -CF2CO2Et, and -C6F5. This methodology relies on the intermolecular [3 + 2] cycloaddition/furan ring-opening triggered by α-fluoroalkyl furfuryl cation with azides to stereoselectively synthesize a series of (E)-fluoroalkyl enone triazoles. The reaction proceeds without metal participation, exhibits excellent substrate tolerance, and has excellent synthetic utility.
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In the present work, the photoinduced charge-transfer (CT) behavior of 7-phenyl-6H-pyrido[1,2-a:3,4-b']diindole-6,13(12H)-dione (HCB) as a function of solvent polarity is reported by UV-vis absorption, steady-state and time-resolved fluorescence, and quantum chemical calculations. Calculated excited state energies of HCB at the B3PW91/6-31+G* level in vacuo and in solvents fulfill the energy requirements for singlet fission, which is the most promising path for the generation of highly efficient solar cells. The calculated potential energy curve for the compound reveals that the keto form is the predominant form in the ground state. Large bathochromic shifts in fluorescence with decreasing trends of quantum yield and lifetime indicate the occurrence of intramolecular CT from the indole bicycle to the indolinone moiety of HCB in highly polar solvents. The observed quenching of HCB fluorescence in different solvents without altering the spectral shape upon addition of a donor, triethylamine, is attributed to intermolecular CT, and it was examined in terms of the Stern-Volmer kinetics. The thermodynamics of photoinduced CT processes in HCB was analyzed using the measured photophysical data and cyclic voltammetric redox potentials via the Rehm-Weller equation. Analyses with the semiclassical Marcus theory suggest that both the CT processes fall under the Marcus normal region.
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In the current era of environmental disasters and the necessity of sustainable development, bacterial endophytes have gotten attention for their role in improving agricultural productivity and ecological sustainability. This review explores the multifaceted contributions of bacterial endophytes to plant health and ecosystem sustainability. Bacterial endophytes are invaluable sources of bioactive compounds, promising breakthroughs in medicine and biotechnology. They also serve as natural biocontrol agents, reducing the need for synthetic fertilizers and fostering environmentally friendly agricultural practices. It provides eco-friendly solutions that align with the necessity of sustainability since they can improve pest management, increase crop resilience, and facilitate agricultural production. This review also underscores bacterial endophytes' contribution to promoting sustainable and green industrial productions. It also presented how incorporating these microorganisms into diverse industrial sectors can harmonize humankind with ecological stability. The potential of bacterial endophytes has been largely untapped, presenting an opportunity for pioneering advancements in sustainable industrial applications. Their importance caught attention as they provided innovative solutions to the challenging problems of the new era. This review sheds light on the remarkable potential of bacterial endophytes in various industrial sectors. Further research is imperative to discover their multifaceted potential. It will be essential to delve deeper into their mechanisms, broaden their uses, and examine their long-term impacts.
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Surface-enhanced Raman scattering (SERS) spectroscopy is still considered poorly reproducible despite its numerous advantages and is not a sufficiently robust analytical technique for routine implementation outside of academia. In this article, we present a self-supervised deep learning-based information fusion technique to minimize the variance in the SERS measurements of multiple laboratories for the same target analyte. In particular, a variation minimization model, coined the minimum-variance network (MVNet), is designed. Moreover, a linear regression model is trained using the output of the proposed MVNet. The proposed model showed improved performance in predicting the concentration of the unseen target analyte. The linear regression model trained on the output of the proposed model was evaluated by several well-known metrics, such as root mean square error of prediction (RMSEP), BIAS, standard error of prediction (SEP), and coefficient of determination (R2). The leave-one-lab-out cross-validation (LOLABO-CV) results indicate that the MVNet also minimizes the variance of completely unseen laboratory datasets while improving the reproducibility and linear fit of the regression model. The Python implementation of MVNet and the code for the analysis can be found on the GitHub page https://github.com/psychemistz/MVNet.
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Furan ring opening reactions are essential in organic synthesis, enabling the incorporation of diverse functional groups and the construction of complex molecular structures. A highly efficient and practical method for synthesizing 2,5-dicarbonyl-3-ene-phosphates from readily available biomass furan and dialkyl phosphonates is reported. The reaction, catalyzed by FeCl3, demonstrated wide substrate scope and high synthetic efficiency. Gram-scale synthesis was achieved, and a one-pot reaction provided a quick access route to the desired compounds. Additionally, a successful Diels-Alder reaction highlighted the versatility of the methodology.
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We report solvent-dependent excited state properties of three difuranone derivatives with a quinoidal backbone by steady-state and lifetime fluorescence measurements and theoretical calculations. Remarkable bathochromic shifts in fluorescence with diminished intensity indicate the occurrence of strong intramolecular charge-transfer transitions in high polar solvents. Cyclic voltammetric redox potentials reveal an interesting variation of biradical characters of the compounds with increasing solvent polarity. Solvent polarity also significantly modulates the energy levels of the charge-transfer (CT) states, as observed from the combined analyses of redox potentials and photophysical data via the Rehm-Weller equation. When high polar solvents favor forward CT by a more exoergic driving force and stabilize the charge-separated states, the reverse CT process diminishes. Estimated free energies of activation for CT suggest that high polar solvents lessen the activation barrier. Calculated excited state energies of the compounds at the CAM-B3LYP/6-31+G* level fulfill the primary conditions required for singlet fission, a process that can substantially increase the efficiency of solar cells, and the crystal packing for compound 1 also reveals a favorable geometry for singlet fission.
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Noise control strategies are extremely important in industry. Acoustic liners and elastic membranes, which absorb or attenuate sound waves, are key components in ducting systems for active and passive noise reduction. In this article, we design and examine a reactive liner panel cavity with flexible interfaces. The lined panel cavity system is comprised of elastic membranes at the interfaces. The aim is to couple the incoming duct modes with the flexible components and then with the localized modes in the lined region. The governing equations for the lined panel cavity system are solved using a mode-matching technique that assures continuity of the normal velocities at the interfaces and can handle a range of strong coupling and higher-order edge conditions in contrast to the coupled mode theory. The aim is to investigate the effects of reactive liners and elastic membrane interfaces on wave scattering through the proposed acoustic enclosure design. The scattering performance of the proposed lined panel cavity is evaluated in terms of the reflected and transmitted energy flux as well as transmission loss. Analysis shows that the resonances at the membrane interfaces coupled to the linear cavities have a direct impact on power variations and the maximum transmission loss.
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Since the publication of the first imaging-guided wire localisation technique, the art of breast treatments has made great strides. Radiologists like Hall, Frank, Kopans, DeLuca, and Homer were all the pioneers in innovative breast interventional radiology field. Their approaches and gadgets for enhancing surgical outcomes in cases with breast diseases aided progress in the discipline and have withstood the ravages of time. Many of their methods are still in use. We are all standing together at the beginning of a new chapter in medicine. Cost effectiveness, comparative effectiveness studies, and an older population are all causing clinicians to reconsider what they perform. Similarly, we are now united on a global scale. The studies described in the current narrative review relate to multiple nations around the world. Breast cancer is a worldwide health problem. With the expansion of technological advances, as well as the apparent ease of worldwide travel, we must all collaborate to improve the outcome in the battle against breast cancer.
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Neoplasias da Mama , Medicina , Humanos , Feminino , Radiologia Intervencionista , Mamografia/métodos , Mama , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Ultrassonografia de IntervençãoRESUMO
Even at high-volume centres, pancreatic resections are linked with a high rate of complications, as well as significant morbidity and mortality. In the management of these occurrences, a multidisciplinary approach is required, and interventional radiology plays an important role in the treatment of patients who develop post-surgical problems. The current review was planned to provide an overview of interventional radiological techniques that can be used to treat various types of problems following pancreatic resection. Percutaneous fluid collection drainage, percutaneous transhepatic biliary operations, artery embolisation, venous interventions, and fistula embolisation are feasible therapeutic alternatives with fewer problems than a re-look surgery. They also have a shorter hospital stay and faster recovery.
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Embolização Terapêutica , Cirurgiões , Humanos , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/terapia , Complicações Pós-Operatórias/etiologia , Pâncreas/diagnóstico por imagem , Pâncreas/cirurgia , Pancreatectomia/efeitos adversosRESUMO
Frass is the main component of worm by-product which exhibit anti-microbial and anti-pathogenic properties. In the present study, we assessed the possibility of mealworm frass in sheep feeding regime and evaluated its effect on health and growth performance of sheep. A total of 09 experimental sheep (18-24 months of age) were grouped into three categories (T1, T3, and T3); each group comprised 3 animals including 2 males and 1 female. Group T1 was considered control, group T2 contains 75% commercial feed and 25 mealworm frass, and T3 was 50:50 of commercial feed and mealworm frass. The sheep in group T2 showed average weight gain of 2.9 kg; however, when the dietary inclusion increased up to 50% of mealworm frass or decreased up to 50% of concentrate feed, the average weight gain decreased up to 2.01 kg (group T3). Moreover, the sheep fed with 25% mealworm frass exhibited the lowest feed refusal percentage (6.33%) in total duration of the dietary period (6 weeks). The highest volume of RBC was found in blood collected from sheep fed within group T2 (10.22 1012/L ± 0.34), followed by sheep fed in group T3 (8.96 × 1012/L ± 0.99) (P < 0.05). Significantly (P < 0.05) highest MCV volume in fL (femtoliter) was found in group T2 (32.83 ± 0.44) followed by group T3 (31.23 ± 0.23). The animals in group T3 showed significantly (P < 0.05) highest MCHC volume (40.47 g/dL ± 0.62) followed by group T2 (38.77 ± 0.97). Similar trend was found in MPV (fL); significantly (P < 0.05) highest MPV volume was found in group T3 (12.63 ± 0.09) followed by group T2 (12.53 ± 0.33). Significantly (P < 0.05) high serum phosphorous (P) (6.00 ± 0.29), TG (60.03 ± 3.11), and TP (7.63 g/dL ± 0.23) levels were found in group T3, followed by animals in group T2. We can conclude that inclusion of mealworm frass to replace 25% commercial concentrate feed improved the growth rate and overall health status of the sheep. The present study laid a foundation for the utilization of the mealworm frass (waste product) in ruminant feeding.
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Hematologia , Tenebrio , Feminino , Masculino , Ovinos , Animais , Dieta/veterinária , Fósforo , Aumento de PesoRESUMO
Background: DNA barcoding is a useful technique for the identification, conservation, and diversity estimation at the species level in plants. The current research work was carried out to characterize selected Fragaria species from northern Pakistan using DNA barcode markers. Methodology. Initially, the efficacy of eight DNA barcode markers was analyzed based on the amplification and sequencing of the genome of selected Fragaria species. The resultant sequences were analyzed using BLAST, MEGA 7.0, and Bio Edit software. The phylogenetic tree was constructed by using Fragaria current species sequences and reference sequences through the neighbor-joining method or maximum likelihood method. Results: Among eight DNA barcode markers, only two (ITS2 and rbclC) were amplified, and sequences were obtained. ITS2 sequence was BLAST in NCBI for related reference species which ranged from 89.79% to 90.05% along with Fragaria vesca (AF163517.1) which have 99.05% identity. Similarly, the rbclC sequence of Fragaria species was ranged from 96% to 99.58% along with Fragaria × ananassa (KY358226.1) which had 99.58% identity. Conclusion: It is recommended that DNA barcode markers are a useful tool to identify the genetic diversity of a species. Moreover, this study could be helpful for the identification of the Fragaria species cultivated in other regions of the world.
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Fragaria , Fragaria/genética , Genoma de Planta , Filogenia , Código de Barras de DNA Taxonômico , Marcadores Genéticos/genéticaRESUMO
A dearomative dimerization of furfuryl azides for the construction of furfuryl triazoles is developed. As a rare leaving group, azide is capable of initiating the generation of a furfuryl cation under the Lewis acid-catalyzed conditions, followed by reacting with the other azide to realize an intermolecular [3 + 2] cycloaddition/furan ring-opening cascade. By extending the reaction time, a fragmentation reaction of resulting furfuryl triazoles occurs to afford 1H-triazoles in high yield. Control studies demonstrated that key furfuryl cations also can be obtained from furfuryl triazoles. Furthermore, a chemoselective cross-cycloaddition can be achieved between furfuryl azides and a benzyl azide.
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Alcinos , Azidas , Catálise , Reação de Cicloadição , Dimerização , TriazóisRESUMO
Triazole phosphonates are valuable structural motifs in chemical biology and the subject of growing recent interest. A novel methodology to synthesize triazolyl phosphonates starting from furfuryl phosphonate alcohols and organo-azides was developed. This method involved an intermolecular copper-catalyzed dearomatized [3 + 2] cycloaddition/furan ring-opening cascade reaction. A strategy involving a three-component reaction was realized for quick access to triazole phosphonates.
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Cobre , Organofosfonatos , Alcinos/química , Catálise , Cobre/química , Reação de Cicloadição , Furanos , Triazóis/químicaRESUMO
BACKGROUND: Assessing health-related quality of life (HRQOL) and its determinants in children may provide a comprehensive view of child health. The study aimed to assess the HRQOL in Indonesian children and its determinants. METHODS: We conducted a community-based cross-sectional study in the Sleman District of Yogyakarta Special Province, Indonesia, from August to November 2019. We recruited children aged 2 to 18 years old using the Sleman Health and Demography Surveillance System sample frame. We used the validated Indonesian version of Pediatric Quality of life Inventory™ (Peds QL™) 4.0 Generic core scale, proxy-reports, and self-reports, to assess the HRQOL. RESULTS: We recruited 633 proxies and 531 children aged 2-18 years. The mean total score of self-report and proxy-report were 89.9+ 8.5 and 93.3 + 6.4. There was a fair to moderate correlation between self-reports and proxy-reports, with intra-class correlation ranging from 0.34 to 0.47, all p < 0.001. Half of the children (49.4% from proxy-report and 50.1% from self-report) reported having acute illness during the last month. Based on proxy-reports, multivariate regression analysis demonstrated lower HRQOL for children with acute health problems, younger age, history of low birth weight, abnormal delivery, lower fathers' educational level, and government-paid insurance for low-income families. CONCLUSION: Sociodemographic determinants of a child's HRQOL, acute health problems, and low birth weight were associated with lower HRQOL in the general pediatric population. In low- and middle-income countries where acute infections and low birth weight are still prevalent, its prevention and appropriate interventions should improve child health.
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Pais , Qualidade de Vida , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Humanos , Indonésia , Inquéritos e QuestionáriosRESUMO
PURPOSE: The aim of this study was to compare the clinical efficacy of injection of 2 long-acting amide local anesthetic agents - bupivacaine and ropivacaine with and without 4 mg dexamethasone in patients undergoing third molar extraction. METHODS: A prospective randomized double blind controlled trial was conducted among 68 patients with impacted mandibular third molars. Group A and B were the control groups and received 1.8 mL of 0.5% bupivacaine hydrochloride and 0.75% ropivacaine hydrochloride, respectively. Group A1 and B1 were experimental groups and received modified twin mixes which were 1.8 mL of 0.5% bupivacaine hydrochloride + 1mL/4mg dexamethasone and 0.75% ropivacaine hydrochloride + 1 mL/4mg dexamethasone, respectively. Visual analog pain scale, mouth opening measurement and facial swelling were assessed at the time of injection and postoperative days 1, 3, and 7. RESULTS: The mean visual analogue scale score for pain on local anesthesia injection was found to be less in both experimental groups- Group A1 (2.94) and B1 (2.41) as compared to control groups- Group A (3.59) and B (3.06). The durations of soft tissue anesthesia were higher as compared to their respective controls for both Group A1 and B1. Patients in both control groups A and B had an increased postoperative swelling, pain and trismus. CONCLUSIONS: Intraoperative and postoperative comfort in both the experimental groups were higher than those for control groups, thereby establishing the clinical efficacy of both modified twin mixes for use in surgical extraction of mandibular third molars.
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Dente Serotino , Dente Impactado , Anestesia Local , Dexametasona , Método Duplo-Cego , Edema/prevenção & controle , Humanos , Dente Serotino/cirurgia , Dor Pós-Operatória/prevenção & controle , Estudos Prospectivos , Extração Dentária , Dente Impactado/cirurgiaRESUMO
The acoustic performance of a silencer containing elastic membranes backed by cavities and porous material is investigated. The modeled waveguide configuration contains porous screens as well as the metallic fairings at interfaces between the inlet and outlet and the expansion chamber. The mode-matching solution is developed to analyze the attenuation of the silencer. The governing eigen-sub-systems are Sturm-Liouville and non-Sturm-Liouville types. In the latter case, the exploitation of generalized orthogonality conditions reveals the point-wise convergence of the solution to the governing eigen-systems. The study shows that by tuning the material parameters of the isotropic membranes and altering the bounding wall conditions, the performance of the physical device can be improved. It enables the model configuration to be adopted as a passive or reactive noise control device.
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Surface-Enhanced Raman Spectroscopy (SERS) is often used for heavy metal ion detection. However, large variations in signal strength, spectral profile, and nonlinearity of measurements often cause problems that produce varying results. It raises concerns about the reproducibility of the results. Consequently, the manual classification of the SERS spectrum requires carefully controlled experimentation that further hinders the large-scale adaptation. Recent advances in machine learning offer decent opportunities to address these issues. However, well-documented procedures for model development and evaluation, as well as benchmark datasets, are missing. Towards this end, we provide the SERS spectral benchmark dataset of lead(II) nitride (Pb(NO3)2) for a heavy metal ion detection task and evaluate the classification performance of several machine learning models. We also perform a comparative study to find the best combination between the preprocessing methods and the machine learning models. The proposed model can successfully identify the Pb(NO3)2 molecule from SERS measurements of independent test experiments. In particular, the proposed model shows an 84.6% balanced accuracy for the cross-batch testing task.
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Nanopartículas Metálicas , Metais Pesados , Aprendizado de Máquina , Reprodutibilidade dos Testes , Análise Espectral RamanRESUMO
The goal of the research was to explore a new green method used to synthesize silver nanoparticles (Ag NPs) from an aqueous extract of Trigonella incise, which serves as a reducing and stabilizing agent. The obtained results showed an 85% yield of nanoparticles by using 2:5 (v/v) of 5% plant extract with a 0.5 M solution of AgNO3. Different techniques were used to characterize the synthesized Ag NPs, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and UV-visible spectroscopy. The UV-visible spectra of green synthesized silver nanoparticles showed maximum absorption at a wavelength of 440 nm. The FT-IR studies revealed the stretching oscillation frequency of synthesized silver nanoparticles in the absorption band near 860 cm-1. Similarly, the bending and stretching oscillation frequencies of the NH function group were assigned to the band in the 3226 cm-1 and 1647 cm-1 regions. The bending vibration of C-O at 1159 cm-1 confirmed the carbonyl functional group that was also assigned to the small intensity band in the range of 2361 cm-1. The X-ray diffraction analysis of Ag NPs revealed four distinct diffraction peaks at 2θ of 38°, 45°, 65° and 78°, corresponds to (111), (200), (220) and (311) of the face-centered cubic shape. The round shape morphology of Ag NPs with a mean diameter in the range 20-80 nm was analyzed via SEM images. Furthermore, the nanoparticles showed more significant antimicrobial activity against Salmonella typhi (S. typhi) and Staphylococcus aureus (S. aureus) with an inhibition zone of 21.5 mm and 20.5 mm at 6 µg/mL concentrations, respectively, once compared to the standard reference. At concentrations of 2 µg/mL and 4 µg/mL, all of the bacterial strains showed moderate activity, with inhibition zones ranging from 11 mm to 18.5 mm. Even at high concentrations of AgNPs, S. typhi showed maximum resistance. The best antifungal activity was observed by synthesized Ag NPs against Candida albicans (C. albicans) with 21 mm zone of inhibition, as compared to a standard drug which gives 22 mm of inhibition. Therefore, we conclude that the antibacterial and antifungal activities showed satisfactory results from the synthesized Ag NPs.
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Anti-Infecciosos , Nanopartículas Metálicas , Trigonella , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antifúngicos/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Prata/química , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus , Difração de Raios XRESUMO
This project purposes to develop chitosan and sodium alginate-based hydrogel membranes loaded with curcumin through microwave-based physical cross-linking technique and its evaluation for wound healing potential. For the purpose, curcumin-loaded chitosan and sodium alginate membranes were developed using microwave at fixed frequency of 2450 MHz, power 350 W for 60 s, and tested for their physicochemical attributes like swelling, erosion, surface morphology, drug content, and in vitro drug release. The membranes were also subjected to tensile strength and vibrational and thermal analysis followed by testing in vivo on animals. The results indicated that microwave treatment significantly enhanced the swelling ability, reduced the erosion, and ensured smooth surface texture with optimal drug content. The drug was released in a slow fashion releasing total of 41 ± 4.2% within 24-h period with a higher tensile strength of 16.4 ± 5.3 Mpa. The vibrational analysis results revealed significant fluidization of hydrophilic domains and defluidization of hydrophobic domains which translated into a significant rise in the melting temperature and corresponding enthalpy which were found to be 285.2 ± 3.2 °C and 4.89 ± 1.4 J/g. The in vivo testing revealed higher percent re-epithelialization (75 ± 2.3%) within 14 days of the treatment application in comparison to only gauze and other treatments applied, with higher extent of collagen deposition having well-defined epidermis and stratum corneum formation. The microwave-treated chitosan-sodium alginate hydrogel membranes loaded with curcumin may prove to be another alternative to treat skin injuries. Graphical Abstract.
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Quitosana , Curcumina , Alginatos , Animais , Hidrogéis , Micro-Ondas , CicatrizaçãoRESUMO
Obstructive sleep apnea (OSA) is a common disease with a high degree of association with and possible etiological factor for several cardiovascular diseases. Patients who are admitted to the Intensive Care Unit (ICU) are incredibly sick, have multiple co-morbidities, and are at substantial risk for mortality. A study of cardiovascular manifestations and disease processes in patients with OSA admitted to the ICU is very intriguing, and its impact is likely significant. Although much is known about these cardiovascular complications associated with OSA, there is still a paucity of high-quality evidence trying to establish causality between the two. Studies exploring the potential impact of therapeutic interventions, such as positive airway pressure therapy (PAP), on cardiovascular complications in ICU patients are also needed and should be encouraged. This study reviewed the literature currently available on this topic and potential future research directions of this clinically significant relationship between OSA and cardiovascular disease processes in the ICU and beyond.