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Within the context of Molecular Electronic Density Theory (MEDT), this study investigates the Diels-Alder reaction among isoprene (2) and R-carvone (1R) applying DFT simulations, with and without Lewis acid (LA) catalysis. The results show that carvone (1R) acts as an electrophile and isoprene (2) as a nucleophile in a polar process. LA catalysis increases the electrophilicity of carvone, thereby improving the reactivity and selectivity of the reaction by reducing the activation Gibbs free energy. Parr functions reveal that the C5=C6 double bond is more reactive than the C9=C10 double bond, indicating chemoselectivity. The examination of the Electron Localization Function (ELF) reveals high regio- and stereoselectivity, indicating an asynchronous mechanism for the LA-catalyzed DA reaction. Furthermore, it is suggested that cycloadduct 3 has great anti-HIV potential because it exhibits lower binding energies than azidothymidine (AZT) in the docking studies of cycloadducts 3 and 4 amongst a primary HIV-1protein (1A8O plus 5W4Q).
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PURPOSE: Adjuvant radiation therapy (ART) after radical cystectomy in locally advanced bladder cancer was revived after the advancement in precise radiation therapy that decreased the normal pelvic tissue radiation hazards. However, there are still scarce controlled randomized studies addressing this issue. METHODS AND MATERIALS: One hundred thirty-one cystectomized urothelial bladder cancer patients were enrolled; 122 were randomized to receive ART of 50 Gy/25 fractions 4 weeks after cystectomy or cystectomy alone (CY). Sixty-two were included in the ART arm and 60 in the CY arm. Twenty-four ART and 30 CY patients received neoadjuvant chemotherapy. Eleven patients (9%) had cotenant neobladder diversion, 6 in ART, and 5 in CY arms. All ART patients were treated with intensity modulated radiation therapy with daily verification cone beam computed tomography. The median follow-up was 42.7 months. RESULTS: The 3-year adjusted locoregional recurrence-free survival rate was higher in the ART arm, measuring 81% (95% CI, 69%-94%) compared with 71% (95% CI, 60%-80%; p = .0457). ART significantly improved the locoregional relapse-free rate in the cystectomy bed and the pelvic side wall (p = .016 and p = .001, respectively). The overall, event-free, and distant metastasis-free survival did not rank to the level of statistical significance in the 2 arms. Even though the acute side effects were slightly higher in ART, the late toxicities were almost equal in the 2 groups. CONCLUSIONS: ART is safe and quite tolerable after radical cystectomy when using precise radiation techniques. These techniques significantly improved the locoregional recurrence-free survival but had insignificant improvement on the overall survival. ART did not affect the distant metastasis-free survival. Similar studies are performed in different centers around the world to confirm the value of ART in urothelial bladder cancer.
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Modifying the metal surface is one solution to the industry's growing corrosion problem. Thus, via threading approach and insertion of copolymers (CoP5-7) containing polyarylidenes through the internal cavity beta-cyclodextrin ß-CD, novel pseudopolyrotaxanes copolymers (PC5-7) are developed, resulting in mild steel corrosion inhibition. Inhibitors of corrosion based on ß-CD molecules adsorb strongly to metal surfaces because of their many polar groups, adsorption centers, many linkages of side chains, and benzene rings. The corrosion inhibition efficiencies IE % statistics have been revised via the Tafel polarization method and Spectroscopy based on the electrochemical impedance (EIS), with PC7 achieving the highest 99.93% in 1.0 M H2SO4; they are mixed-type inhibitors. The chemical composition of the resulting PCs is determined with Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) is utilized to examine the morphological structure of the produced polymers, and X-ray diffraction is employed to identify crystallinity. Encapsulating CoP5-7 with ß-CD changes the morphological structures and increases the generated PCs' crystallinity. The thermal stability of PCs is studied, indicating the presence of these CoPs within the ß-CD cavities enhances their thermal stability. This research will be a stepping stone for developing high-efficiency anti-corrosion coatings and various industrial applications.
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In this study, 2-[(E)-(hexylimino)methyl] phenol (SA-Hex-SF) was synthesized by adding salicylaldehyde (SA) and n-hexylamine (Hex-NH2), which was subsequently reduced by sodium borohydride to produce 2-[(hexylamino)methyl] phenol (SA-Hex-NH). Finally, the SA-Hex-NH reacted with formaldehyde to give a benzoxazine monomer (SA-Hex-BZ). Then, the monomer was thermally polymerized at 210 °C to produce the poly(SA-Hex-BZ). The chemical composition of SA-Hex-BZ was examined using FT-IR, 1H, and 13C NMR spectroscopy. Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray Diffraction (XRD), respectively, were used to examine the thermal behavior, surface morphology, and crystallinity of the SA-Hex-BZ and its PBZ polymer. Mild steel (MS) was coated by poly(SA-Hex-BZ) which was quickly prepared using spray coating and thermal curing techniques (MS). Finally, the electrochemical tests were used to evaluate the poly(SA-Hex-BZ)-coating on MS as anti-corrosion capabilities. According to this study, the poly(SA-Hex-BZ) coating was hydrophobic, and corrosion efficiency reached 91.7%.
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The reaction of the starting compound, 7-acetyl-4-cyano-1,6-dimethyl-8-phenyl-7,8-dihydroisoquinoline-3(2H)-thione, with some N-aryl-2-chloroacetamides or chloroacetonitrile, in the presence of sodium acetate trihydrate, gave the corresponding substituted 3-methylsulfanyl-7-acetyl-4-cyano-1,6-dimethyl-8-phenyl-7,8-dihydroisoquinolines. Upon heating of the latter compounds with sodium methoxide in methanol, they underwent intramolecular Thorpe-Zeigler cyclization, affording the target isomers 1-amino-2-(substituted)-5,8-dimethyl-6-phenyl-6,7-dihydrothieno[2,3-c]isoquinolines (DHTIQs). The chemical structures of all produced substances were characterized by elemental and spectral analyses. The photophysical characteristics of the produced DHTIIQs (He1-Ph-Cl, He2-Ph-CH3, He3-Ph, and He4-CN) have been investigated as luminous compounds. Potentiodynamic, surface morphology, and theoretical calculations were used to study the behavior of the synthesized DHTIQs as corrosion inhibitors on mild steel in a 1.0 M sulfuric acid solution.
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To develop innovative mesoporous crosslinked poly(azomethine- sulfone)s with environmental applications, a simple Schiff base condensation technique based on barbituric acid BA or condensed terephthaldehyde barbituric acid TBA in their structures as monomeric units are applied. Different analysis methodologies and viscosity measurements identify them as having stronger heat stability and an amorphous structure. The photophysical features of the multi stimuli response MSR phenomenon are observable, with white light emission at higher concentrations and blue light emission at lower concentrations. Their emission characteristics make them an excellent metal ions sensor through diverse charge transfer methods. They can have a better inhibition efficiency and be employed as both mixed-type and active corrosion inhibitors according to their fluorescence emission with metals, demonstrating their capacity to bind with diverse metals. The adsorption of two distinct dye molecules, Methylene blue MB cationic and sunset yellow SY anionic, on the mesoporous structures of the polymers is investigated, revealing their selectivity for MB dye adsorption. Quantum studies support these amazing discoveries, demonstrating a crab-like monomeric unit structure for the one that is heavily crosslinked.
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Corantes , Azul de Metileno , Adsorção , Compostos Azo , Corantes/química , Azul de Metileno/química , Porosidade , Sulfonas , TiossemicarbazonasRESUMO
PURPOSE: Temporomandibular joint disc repositioning surgery is 1 of the treatment modalities used for treating anterior disc displacement of the temporomandibular joint. The procedure can be arthroscopic disc repositioning or open disc repositioning. This systematic review measured and compared the efficacy of arthroscopic and open disc repositioning procedures. MATERIALS AND METHODS: The authors conducted a systematic review without meta-analysis by performing a literature search electronically and manually covering arthroscopic and open disc repositioning studies published up to July 2020 in Pubmed, Embase, and Cochrane databases. Surgical outcomes such as changes in maximal incisal opening (MIO) and pain scores, temporomandibular joint noises, diet consistency, malocclusion, and postoperative complications were extracted and analyzed. RESULTS: A total of 28 studies were included in the review and split into those assessing open disc repositioning (n = 13) and those assessing arthroscopic disc repositioning (n = 15). The average age of the study patients in the included studies was 31.5 ± 6.8 years, and women represented 83.3% of the study population. Both arthroscopic and open disc repositioning showed to be efficacious in reducing pain and increasing MIO. Due to heterogeneity in study designs and data reporting between the studies, no quantitative analysis was performed, and the groups were not directly compared. CONCLUSIONS: Both arthroscopic and open disc repositioning led to significant improvements in clinical outcomes based on pain scores and MIO. This study highlights the need for comparative studies of the 2 techniques with well-documented case selection including standardized diagnosis based on Wilkes stages and rigorous outcomes assessment including patient reported outcomes.
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Luxações Articulares , Adulto , Artroscopia , Feminino , Humanos , Imageamento por Ressonância Magnética , Amplitude de Movimento Articular , Articulação Temporomandibular , Disco da Articulação Temporomandibular/cirurgia , Resultado do Tratamento , Adulto JovemRESUMO
PURPOSE: The purpose of the present study was to correlate specific arthroscopic findings in temporomandibular joint (TMJ) arthroscopy and histologic results from arthroscopic-guided synovial biopsy. PATIENTS AND METHODS: A retrospective cohort study was completed of patients who had undergone arthroscopy and arthroscopic synovial biopsy from January 1, 2011 to March 31, 2016 at the senior author's practice in Miami, Florida. The demographic, arthroscopic, histologic, serologic, and historical variables were recorded by electronic medical record review. Two-tailed Fisher's exact tests were used to test the correlation of the arthroscopic and histologic variables. RESULTS: A total of 210 patients were included in the present study. The mean age was 43.1 ± 18.8 years, and the study population included 91.7% women. The following histologic findings had significant associations: lymphoplasmacytic infiltrate with petechiae synovitis (P = .0018), chronic inflammation with joint stenosis (P = .019), and crystal deposition with visualization of crystals (P = .0472). Hyperplastic synovium found on histologic examination was associated with both petechiae synovitis and adhesions. Histologic vascular proliferation was associated with synovial plica and joint stenosis. CONCLUSIONS: The findings from the present study indicated an association between specific findings during arthroscopy and histologic findings. A prospective study is required to validate the findings to evaluate their utility in patient care.
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Sinovite , Transtornos da Articulação Temporomandibular , Adulto , Artroscopia , Feminino , Florida , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Membrana Sinovial , Articulação Temporomandibular , Adulto JovemRESUMO
OBJECTIVES: This study aims to compare the stress distribution and displacement that resulted from the use of a Gerber space regainer and sagittal distalizer using three-dimensional finite element analysis. MATERIALS AND METHODS: Three-dimensional simulated models of the appliances were developed using a software. The forces applied by the two appliances were 3N (tipping) and 15N (bodily), respectively. Displacement and von Mises stress on the compact and cancellous bone, periodontal ligament (PDL), crowns of the mandibular first, second permanent molars, and deciduous canines were calculated. Stress distribution and displacement values were measured via linear static analysis. RESULTS: Gerber space regainer showed greater displacement than that produced by the sagittal distalizer at the first permanent molar. However, such displacement was less at the other tested points when compared with that delivered by sagittal distalizer. The stresses created by Gerber appliance were higher in the crown and PDL of the deciduous canine than the crown of the first permanent molar crown. CONCLUSIONS: Gerber appliance generates more distal force and less stress concentration on the crown of the mandibular first permanent molar than that created by the sagittal distalizer. On the other hand, stress concentrations produced by Gerber space regainer are found to be more on the crown and PDL of the deciduous canine. Therefore, it can be concluded that the use of Gerber appliance needs more anchorage.
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PURPOSE: Total joint replacement is the recommended treatment for end-stage temporomandibular joint (TMJ) disease. The goal of treatment is to help the return to acceptable function with improvement of the maximum incisal opening (MIO) and a reduction of pain. When a prosthetic joint shows late complications, surgical management includes an open approach, with debridement, cultures, and prosthetic replacement as options. The purpose of the present study was to evaluate the early outcomes of arthroscopic management of failing prosthetic TMJs (PTMJs). PATIENTS AND METHODS: The inclusion criteria were patients with custom or stock joints with complaints of limitation of mouth opening and pain, who had undergone arthroscopy. The exclusion criteria were patients with radiographic heterotopic bone formation, improvement with antibiotic treatment, and failed hardware found on imaging studies. RESULTS: A total of 9 patients were included in the present study (all women), with 5 unilateral and 4 bilateral PTMJs, for a total of 13 sides that underwent arthroscopy. Their mean age was 40 years (range, 23 to 65 years). The mean preoperative MIO was 25 mm, and the mean preoperative visual analog scale for pain and functional limitation scores were both 8 of 10. The corresponding scores were 4 of 10 and 3 of 10 at 3 months postoperatively. CONCLUSIONS: Arthroscopic management of prosthetic joints has been reported in orthopedic studies, with benefits shown in the diagnosis and management of synovial impingement and arthrofibrosis. The results from the present study demonstrated that the early clinical outcomes of arthroscopic management of PTMJs is promising for decreasing pain and increasing the MIO. Larger studies with longer follow-up are needed to further classify the different causes of prosthetic failure and advance the approaches to management.
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Artroplastia de Substituição , Prótese Articular , Transtornos da Articulação Temporomandibular/cirurgia , Adulto , Idoso , Artroscopia , Feminino , Humanos , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Articulação Temporomandibular/cirurgia , Resultado do Tratamento , Adulto JovemRESUMO
Sodium-glucose cotransporter 2 (SGLT2) inhibitors are newly introduced hypoglycemic drugs that work by inhibiting glucose reabsorption at proximal renal tubules. The use of SGLT2 inhibitors in nontransplant diabetic patients with or without cardiovascular disease has well-established efficacy and safety. The risks of renal graft dysfunction and urinary tract infections might be the limiting factors for their use in renal transplant patients. Data regarding the safety and long-term efficacy of SGLT2 inhibitors use in diabetic renal transplant patients is scanty. The aim of the study is to report our experience with use of SGLT2 inhibitors in 8 diabetic renal transplant patients supported by literature review. Eight diabetic renal transplant patients were recruited from Tawam hospital during the period between June 2016 and January 2019. Demographic, clinical, and laboratory data were collected and analyzed. Adding SGLT2 resulted in significant decrease in hemoglobin A1c and body mass index after 12 months of treatment. There was significant negative correlation between the duration of treatment with SGLT2 and hemoglobin A1c. Diabetic renal transplant patients with stable kidney function had better glycemic control with use of SGLT2 inhibitors. There was no deterioration of kidney function and risk of recurrent urinary tract infection was low.
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Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Transplante de Rim , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transportador 2 de Glucose-SódioRESUMO
Advances in technology and specialized instrumentation allow surgeons to study, refine, and modify minimally invasive surgery (MIS) to replace standard operations. This has occurred across many surgical specialties. The benefits of MIS include less swelling, less pain, shorter hospital stay, and faster return to daily activities. Oral and maxillofacial endoscopic techniques are used for access to the ramus condyle unit, maxillary sinus, zygoma, orbit, temporomandibular joint, and salivary ductal system. Although endoscopic techniques are also used in facial cosmetic surgery, this discussion focuses on noncosmetic procedures.
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Endoscopia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Cirúrgicos Bucais/métodos , Procedimentos de Cirurgia Plástica , Humanos , Procedimentos de Cirurgia Plástica/métodosRESUMO
With the advancement in metabolic engineering technologies, reconstruction of the genome of host organisms to achieve desired phenotypes can be made. However, due to the complexity and size of the genome scale metabolic network, significant components tend to be invisible. We proposed an approach to improve metabolite production that consists of two steps. First, we find the essential genes and identify the minimal genome by a single gene deletion process using Flux Balance Analysis (FBA) and second by identifying the significant pathway for the metabolite production using gene expression data. A genome scale model of Saccharomyces cerevisiae for production of vanillin and acetate is used to test this approach. The result has shown the reliability of this approach to find essential genes, reduce genome size and identify production pathway that can further optimise the production yield. The identified genes and pathways can be extendable to other applications especially in strain optimisation.
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Deleção de Genes , Regulação Fúngica da Expressão Gênica , Genoma Fúngico , Metaboloma/genética , Modelos Genéticos , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismoRESUMO
Reconstructions of genome-scale metabolic networks from different organisms have become popular in recent years. Metabolic engineering can simulate the reconstruction process to obtain desirable phenotypes. In previous studies, optimization algorithms have been implemented to identify the near-optimal sets of knockout genes for improving metabolite production. However, previous works contained premature convergence and the stop criteria were not clear for each case. Therefore, this study proposes an algorithm that is a hybrid of the ant colony optimization algorithm and flux balance analysis (ACOFBA) to predict near optimal sets of gene knockouts in an effort to maximize growth rates and the production of certain metabolites. Here, we present a case study that uses Baker's yeast, also known as Saccharomyces cerevisiae, as the model organism and target the rate of vanillin production for optimization. The results of this study are the growth rate of the model organism after gene deletion and a list of knockout genes. The ACOFBA algorithm was found to improve the yield of vanillin in terms of growth rate and production compared with the previous algorithms.
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Recently, the greatest statistical computational challenge in genetic epidemiology is to identify and characterize the genes that interact with other genes and environment factors that bring the effect on complex multifactorial disease. These gene-gene interactions are also denoted as epitasis in which this phenomenon cannot be solved by traditional statistical method due to the high dimensionality of the data and the occurrence of multiple polymorphism. Hence, there are several machine learning methods to solve such problems by identifying such susceptibility gene which are neural networks (NNs), support vector machine (SVM), and random forests (RFs) in such common and multifactorial disease. This paper gives an overview on machine learning methods, describing the methodology of each machine learning methods and its application in detecting gene-gene and gene-environment interactions. Lastly, this paper discussed each machine learning method and presents the strengths and weaknesses of each machine learning method in detecting gene-gene interactions in complex human disease.