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1.
Cureus ; 16(1): e51517, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38304682

RESUMO

Objective This study aimed to compare the efficiency of corrugated rubber drains and sutures in preventing complications after the surgical removal of impacted mandibular molars. Methodology Sixty patients enrolled for surgical extraction of wisdom teeth were studied. The patients were divided into two groups of 30. After extraction, Group A received a corrugated flat rubber drain and Group B had only conventional knotted sutures in the extraction site. Patients were evaluated for postoperative pain, edema, and trismus. Before the procedure and on postoperative days 1, 2, and 7, all parameters were measured and compared. Results Patients in Group A with surgical drains showed a significant reduction in all postoperative challenges in contrast to Group B with normal sutures. The intergroup comparison indicates that pain was highest before surgery and showed a significant reduction by day 7 in both groups. Similarly, trismus was also at its peak before surgery for both groups. However, in contrast to Group A, Group B with suturing alone demonstrated a substantial reduction in trismus by day 7. By the end of day 7, edema had substantially decreased in both groups, but it was not statistically significant (P < 0.05). Conclusions The placement of surgical drains and the use of sutures alone have both shown similar and significant benefits in preventing postoperative challenges. However, intraoral drainage with a flat drain after mandibular third molar removal showed a significant reduction of pain, as measured by the visual analog scale (VAS) scale, or postoperative swelling.

2.
Cancers (Basel) ; 15(22)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38001584

RESUMO

The field of lifestyle medicine in cancer care and survivorship is undergoing significant transformation, presenting both challenges and opportunities. This collection of insights and reflections by an esteemed speaker aims to address critical facets of this evolving landscape and the intersection of healthcare, lifestyle, and cancer. With a focus on optimizing the health of cancer survivors, the speaker emphasizes the correlation between general population health and strategies for mitigating cancer risk. Evidence-based resources have a key role in their comprehensive insights into lifestyle changes' role in cancer prevention and survivorship. Lifestyle interventions also have a promising role in mitigating the late effects in the pediatric context. Therefore, encouraging the early adoption of healthy practices in childhood cancer survivors emerges as a pivotal strategy. Furthermore, challenges in enhancing education and access to lifestyle medicine are addressed. This highlights the importance of patient-centered communication, motivational interviewing, and personalized guidance in facilitating lifestyle changes with patients. Finally, the role of nutritionists in advising breast cancer patients to consider calorie restriction to lower IGF-1 levels is explored. This collection underscores the multifaceted nature of lifestyle medicine in cancer care, highlighting challenges, opportunities, and the transformative power of passion and curiosity in shaping healthcare careers.

3.
Cancers (Basel) ; 15(21)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37958344

RESUMO

This perspective delves into the evolving landscape of Myelodysplastic Syndrome (MDS) treatment. MDS presents a significant clinical challenge, often progressing to acute myeloid leukemia. For low-risk MDS, the emphasis is on personalized care through comprehensive risk assessment, clinical monitoring, and tailored interventions, including promising agents like erythropoiesis-stimulating agents, lenalidomide, and luspatercept, with the anticipation of an expanding therapeutic arsenal and early intervention for improved outcomes. In contrast, high-risk MDS treatment is evolving towards upfront doublet or triplet therapies with a focus on minimal residual disease (MRD) monitoring. A holistic approach integrates various modalities, including stem cell transplant and post-transplant maintenance, all guided by individual patient circumstances. Risk-adapted strategies are crucial for enhancing patient outcomes. Precision medicine for MDS treatment is budding, largely driven by Next Generation Sequencing (NGS). NGS aids in early diagnosis, prognostication, and the targeting of specific mutations, with molecular data increasingly informing treatment responses and allowing for tailored interventions. Clinical trials within homogeneous patient groups with similar molecular profiles are becoming more common, enhancing treatment precision. In conclusion, the future of MDS treatment is moving towards personalized medicine, leveraging advanced technologies like NGS and molecular insights to improve outcomes in the realm of hematological malignancies.

4.
J Hematol Oncol ; 16(1): 39, 2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055774

RESUMO

Cancer patients, due to their immunocompromised status, are at an increased risk for severe SARS-CoV-2 infection. Since severe SARS-CoV-2 infection causes multiple organ damage through IL-6-mediated inflammation while stimulating hypoxia, and malignancy promotes hypoxia-induced cellular metabolic alterations leading to cell death, we propose a mechanistic interplay between both conditions that results in an upregulation of IL-6 secretion resulting in enhanced cytokine production and systemic injury. Hypoxia mediated by both conditions results in cell necrosis, dysregulation of oxidative phosphorylation, and mitochondrial dysfunction. This produces free radicals and cytokines that result in systemic inflammatory injury. Hypoxia also catalyzes the breakdown of COX-1 and 2 resulting in bronchoconstriction and pulmonary edema, which further exacerbates tissue hypoxia. Given this disease model, therapeutic options are currently being studied against severe SARS-COV-2. In this study, we review several promising therapies against severe disease supported by clinical trial evidence-including Allocetra, monoclonal antibodies (Tixagevimab-Cilgavimab), peginterferon lambda, Baricitinib, Remdesivir, Sarilumab, Tocilizumab, Anakinra, Bevacizumab, exosomes, and mesenchymal stem cells. Due to the virus's rapid adaptive evolution and diverse symptomatic manifestation, the use of combination therapies offers a promising approach to decrease systemic injury. By investing in such targeted interventions, cases of severe SARS-CoV-2 should decrease along with its associated long-term sequelae and thereby allow cancer patients to resume their treatments.


Assuntos
COVID-19 , Neoplasias , Humanos , SARS-CoV-2 , Interleucina-6 , Neoplasias/complicações , Neoplasias/terapia , Hipóxia
5.
Am J Forensic Med Pathol ; 44(1): e8-e9, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36194653

RESUMO

ABSTRACT: A case of infective endocarditis of a dysplastic pulmonic valve along with atrial septal defect has been described. Right-sided endocarditis has now increased in frequency because of cardiac invasive procedures and intravenous drug abuse. Although the tricuspid valve usually bears the brunt of right-sided endocarditis, there have now been increasing reports of pulmonary valve infective endocarditis.


Assuntos
Endocardite Bacteriana , Endocardite , Cardiopatias Congênitas , Comunicação Interatrial , Valva Pulmonar , Humanos , Valva Tricúspide , Comunicação Interatrial/complicações
6.
Neurol India ; 70(6): 2411-2415, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36537425

RESUMO

Background: Stroke is an important cause of mortality with intracranial atherosclerosis as an important risk factor. Geographical variation in the pattern of atherosclerosis is well documented with various studies in stroke patients showing that African Americans and Japanese people tend to have intracranial vascular occlusion, whereas Caucasians more often have extracranial atherosclerotic lesions. Methods: This is a prospective study of 50 cases of Indian elderly patients over 60 years of age where we have studied the CNS vasculature in detail including intracranial atherosclerosis with regards to its incidence, severity, distribution, plaque composition and associated risk factors. We compared the atherosclerotic pathology in the intracranial vessels and the extracranial vessels including the carotids. Results: Out of 50 cases 31 showed intracranial atherosclerosis. Anterior circulation was more commonly affected. A total of 87 of the intracranial arteries showed atherosclerotic plaques, most common nature of the plaques being fibrofatty. Majority of the intracranial vessels showed mild stenosis and multiple vessels were involved in 15 cases while single vessel involvement was seen in 16 cases with the middle cerebral artery being the most common single vessel involvement. Infarcts were seen in 7 cases and all these cases had history of hypertension. Cerebral atrophy was seen in 28 cases. All cases showing frontoparietal and generalized atrophy had carotid artery stenosis. Of the 100 carotid arteries studied (2 per case) 59 showed atherosclerosis. Majority of the carotid arteries showed mild degree of atherosclerosis and the content was predominantly fatty. Conclusion: This study concludes that the pattern of atherosclerosis is different in the Indian population as compared to the western literature. Intracranial atherosclerosis is more common in Indian population with the anterior portion of circle of Willis being more commonly affected.


Assuntos
Aterosclerose , Arteriosclerose Intracraniana , Placa Aterosclerótica , Acidente Vascular Cerebral , Humanos , Idoso , Pessoa de Meia-Idade , Estudos Prospectivos , Autopsia , Aterosclerose/complicações , Acidente Vascular Cerebral/etiologia , Placa Aterosclerótica/complicações , Artéria Cerebral Média , Fatores de Risco
7.
Saudi J Biol Sci ; 29(5): 3815-3821, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35844361

RESUMO

The major aspects of using plant-derived medications are significantly safer and secure than synthetic ones. The n-hexane seed extract of ayurvedic medicinal plants Myristica fragrans was also utilized as food ingredients have analyzed for phytochemical existence by Gas Chromatography-mass spectrometry (GC-MS). Twenty-three phytoconstituents were identified with elemicin (24.44%) as the major constituent. Lipid peroxidase, catalase and DPPH assays were performed using the isolated elemicin and the results revealed significant antioxidant activity. The antibacterial study revealed that elemicin showed MIC of 31.25 µg/mL against Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi, and 62.5 µg/mL against Klebsiella pneumonia and Staphylococcus aureus. Elemicin exhibited better antifungal activity against Candida tropicalis and Aspergillus flavus than Aspergillus niger, Penicillium chrysogenum and Trichophyton rubrum. The study implies that the elemicin isolated from Myristica fragrans possess promising bioactive properties and can be crucially utilized in the development of therapeutic agents and food preservatives.

8.
J Am Nutr Assoc ; 41(8): 826-830, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34402418

RESUMO

Helicobacter pylori plays a consequential role in gastric inflammations and ulceration. The cure for the same was researched and identified to be the triple therapy regime. Intensive research in the field also proved that altering the food habits during ulcers will be a major factor in the time period that is required for cure. Fermented foods usage dates back to ancient civilizations, but their role in maintaining gastric health are slowly being uncovered. One such major role reported will be the bacterial check that the probiotics in fermented food do in human gastrointestinal tract. Various species of bacteria present in the fermented products will lead to reduction of the H. Pylori infection in the GI tract.Key teaching pointsMicrobes that are active in fermented foods reduce inflammation and improve histological conditions of ulcers caused due to H. pylori.Microbes such as Lactobacillus that were in fermented products when tested showed inhibitory effects, decreasing infection density and reducing mucus depletion.Lactic fermented products showed a decrease in urease activity and reduces H. pylori adhesion through various organic acid secretions.Organisms in fermented products involve various mechanisms like lowering gut pH, improving immunological responses, scavenging free radicals and so on.Fermented foods have many modulatory effects that help fighting and curing gastric ulcers.


Assuntos
Alimentos Fermentados , Infecções por Helicobacter , Helicobacter pylori , Úlcera Gástrica , Humanos , Úlcera Gástrica/microbiologia , Úlcera
9.
Lung India ; 38(5): 442-447, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34472522

RESUMO

CONTEXT: In this autopsy study, the various morphological patterns of acute respiratory distress syndrome (ARDS) have been analyzed and compared along with their etiopathogenesis. AIMS: We aimed to study the prevalence and clinicopathological correlation of ARDS based on age, gender, hospital stay, symptoms, clinical diagnosis, gross, and microscopy findings. SUBJECTS AND METHODS: Total 130 cases of ARDS were studied over a period of 5 years. Age, gender, hospital stay duration, symptoms, clinical diagnosis, gross and microscopic lung finding, clinicopathological correlation, and cause of death were documented and analyzed. Special stains were done whenever required. STATISTICAL ANALYSIS: This is an observational study, and simple statistics such as mean, median, and standard deviation have been used for continuous variables. RESULTS: The prevalence of ARDS among the adult autopsy was 6.05%. Majority of the cases were in the age group of 18-30 years (36.9%), with a male: female ratio of 1.7:1. Chief complaints were fever (71%), breathlessness (54.6%), and chills (43.8%). The main clinical diagnoses were ARDS (41.6%), sepsis (28.3%), acute febrile illness (17%), and lower respiratory tract infection (12.5%). Most of the patients had a hospital stay of <1 day. Associated conditions mostly included chronic alcoholism (16.1%), pregnancy (16.1%), and chronic smoking (10.7%). Major findings on gross examination were intrapulmonary hemorrhage (38.5%), ARDS (33%), pulmonary edema (13%), and pneumonia (15.3%).On microscopy, major findings were hyaline membrane (84.6%), intrapulmonary hemorrhage (76.1%), pulmonary edema (75.3%), organizing fibrin (55.3%), and bronchopneumonia (36.2%). CONCLUSION: Infections were one of the major predisposing causes of ARDS. Due to the short interval, the underlying cause for ARDS often goes undiagnosed.

10.
Eur J Mass Spectrom (Chichester) ; 26(1): 36-45, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31234644

RESUMO

Sequence determination of peptides using mass spectrometry plays a crucial role in the bottom-up approaches for the identification of proteins. It is crucially important to minimise false detection and validate sequence of the peptides in order to correctly identify a protein. Chemical modification of peptides followed by mass spectrometry is an option for improving the spectral quality. In silico-derived tryptic peptides with different N-terminal amino acids were designed from human proteins and synthesized. The effect of acetylation on the fragmentation of peptides was studied. N-terminal acetylation of the tryptic peptides was shown to form b1-ions, improve the abundance and occurrence of b-ions. In some cases, the intensity and occurrence of some y-ions also varied. Thus, it is demonstrated that acetylation plays an important role in improving the de novo sequencing efficiency of the peptides. The acetylation method was extended to tryptic peptides generated from the proteome of an Antarctic bacterium Pseudomonas syringae Lz4W using the proteomics work flow and mass spectra of the peptides were analysed. Comparison of the MS/MS spectra of the acetylated and unacetylated peptides revealed that acetylation helped in improving the spectral quality and validated the peptide sequences. Using this method, 673 proteins of the 1070 proteins identified were validated.


Assuntos
Peptídeos/química , Acetilação , Proteínas de Bactérias/química , Humanos , Proteínas/química , Proteômica , Pseudomonas syringae/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
11.
J Nanosci Nanotechnol ; 18(4): 2405-2414, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442909

RESUMO

While many naturally occurring polysaccharides have been widely used as drug carriers, there are two main drawbacks in their use: the first is their physical properties such as molecular weight, branching, type of glycosidic linkages and solubility depend on their source and the method of isolation and purification, the second is many of them are contaminated with proteins and protein removal is essential for preventing immune reactions. Synthetic polysaccharides on the other hand can be tailor made from their respective monomers with consistent physical properties and are, free from protein contamination, both being significant advantages in their use. Although, the synthesis of polysaccharides such as polyglucose, polymannose, polygalactose etc., by the polycondensation of their respective monomers have been reported more than half a century ago, their use as drug carriers have not received any attention so far. In this report, we show that polyglucose (PG) having a weight average molar mass of 37,000 g/mol can be synthesized in a single step by the melt polycondensation of glucose in over 70% yield. Oxidation using sodium periodate generated aldehyde functions on the polymer. Amphotericin B, (AmB) a water-insoluble polyene antibiotic was chosen as a model drug to couple onto periodate oxidized PG via imine linkage at ~20 wt% concentration. The drug loading capacity of the conjugates was above 90%. Further reduction using sodium borohydride gave the more stable amine conjugates with any residual aldehyde on the polymer backbone getting reduced to hydroxyl groups. The conjugates were highly soluble in water and stable on storage. At ten times the concentration of AmB, the conjugates produced negligible hemolysis to human blood. The AmB conjugates were then evaluated for their anti-fungal activity against C. albicans and A. fumigatus and anti-leishmanial activity against different strains of L. donovani in culture. The conjugates showed potent anti-fungal and anti-leishmanial activity. The use of synthetic polysaccharides in drug delivery and in other biomedical applications will have many potential advantages.


Assuntos
Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Portadores de Fármacos , Polissacarídeos , Candida albicans , Glucanos , Humanos , Leishmaniose/tratamento farmacológico
12.
Eur J Mass Spectrom (Chichester) ; 24(2): 231-242, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29264929

RESUMO

A wide variety of post-translational modifications such as oxidation, phosphorylation, glycosylation, methylation, and acetylation play critical roles in cellular functions. Detection of post-translational modifications in proteins is important to understand their crucial roles in cellular functions. Identifying each modification requires special attention in mass spectral acquisition and analysis. Here, we report a mass spectral method for the detection of multiple phosphorylations in peptides by analyzing their products after fragmentation. Synthetic peptides were used to identify these modifications by matrix-assisted laser desorption/ionization (MALDI) TOF/TOF. Peptides with serine, threonine, and tyrosine were used with mono- to tetra-phosphorylation sites in different combinations to get insights into their fragmentation and identify the location of these sites. The y-ion series were observed without the loss of phosphate groups and were thus very useful in determining the localization and sequence of the phosphate residues. Acetylation of the peptides was found to be useful in detecting the b1-ion and helped in identifying the N-terminus. When a mixture of the phosphorylated peptides (from mouse protein sequences) were analyzed by LC-MS/MS on a Velos Orbitrap Mass Spectrometer and the data subjected to analysis by Sequest using the mouse database, the peptides were identified along with the parent proteins. A comparison of MALDI TOF/TOF spectra with ESI MS/MS helped in eliminating falsely discovered peptides using the database search.


Assuntos
Peptídeos/química , Fosfatos/química , Espectrometria de Massas em Tandem/métodos , Acetilação , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Bases de Dados de Proteínas , Glicosilação , Metilação , Camundongos , Oxirredução , Fosforilação , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
13.
Dermatopathology (Basel) ; 3(2): 36-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27504443

RESUMO

Bednar tumor is an uncommon variant of dermatofibrosarcoma protuberans. Also known as pigmented dermatofibrosarcoma protuberans, this tumor is of intermediate grade. It is seen in adults and has a predisposition to affect the shoulder region. We report a rare case of Bednar tumor in a 40-year-old female patient. The diagnosis of Bednar tumor must be considered while reporting pigmented subcutaneous spindle cell lesions.

14.
Indian J Chest Dis Allied Sci ; 58(1): 37-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28393511

RESUMO

Miliary multi-focal bilateral pulmonary adenocarcinoma with lepidic predominant pattern is an unusual morphological presentation and is seen in females who are non-smokers. This gross morphology can be confused with infectious diseases, like tuberculosis, histoplasmosis or with pulmonary metastasis.


Assuntos
Adenocarcinoma/patologia , Neoplasias Pulmonares/patologia , Idoso , Evolução Fatal , Feminino , Humanos
15.
Indian J Pathol Microbiol ; 58(4): 516-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26549080

RESUMO

Primary salivary gland-type tumors of the lung and airways being unusual, they pose a diagnostic challenge on small biopsies and are usually consigned as non-small cell lung carcinomas. Since the clinical behavior of these tumors is different from the conventional lung tumors, it is important to accurately diagnose them. Among this category of tumors, adenoid cystic carcinoma (ACC) of the lungs and airways is exceedingly rare. Few large studies and maximum case reports have been reported in literature on ACC of the lungs and trachea so far. We herein report a rare case of primary ACC of the trachea diagnosed on bronchoscopic biopsy.


Assuntos
Carcinoma Adenoide Cístico/diagnóstico , Neoplasias Pulmonares/diagnóstico , Neoplasias da Traqueia/diagnóstico , Adulto , Carcinoma Adenoide Cístico/cirurgia , Humanos , Pulmão/patologia , Pulmão/cirurgia , Neoplasias Pulmonares/cirurgia , Masculino , Traqueia/patologia , Traqueia/cirurgia , Neoplasias da Traqueia/cirurgia , Resultado do Tratamento
16.
J Indian Soc Pedod Prev Dent ; 33(3): 213-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26156275

RESUMO

INTRODUCTION: Molar incisor hypomineralization (MIH) describes the clinical picture of hypomineralization of systemic origin affecting one or more first permanent molar. There is a rarity of prevalence studies in Indian population. OBJECTIVES: The main aim of this study was to investigate the prevalence of MIH in a population of South Indian children. SETTINGS AND DESIGN: A cross-sectional epidemiological survey, included 2000 children aged 11-16 years chosen by stratified random sampling from government and private schools of Davangere, a city in South India. MATERIALS AND METHODS: Evaluation of MIH and decayed, missing and filled teeth was carried out in these children by a calibrated examiner. The severity of hypomineralization was recorded according to the Wetzel and Reckel scale. STATISTICAL ANALYSIS: Chi-square test was used to analyze the categorical data. P ≤ 0.05 was considered for statistical significance. RESULTS: About 8.9% of all examined children showed at least one ill-structured first permanent molar in terms of MIH. The male and female ratio was found to be 1:1.1. The decreasing order of occurrence of MIH affected teeth were permanent maxillary molars, maxillaryincisors, mandibular molars and the mandibular incisors. CONCLUSION: The prevalence of MIH in the permanent dentition of south Indian children was 8.9%. There is a need for a proper planned preventive and restorative program with regard to the increasing prevalence of MIH.


Assuntos
Hipoplasia do Esmalte Dentário/epidemiologia , Adolescente , Criança , Cidades/epidemiologia , Estudos Transversais , Hipoplasia do Esmalte Dentário/patologia , Dentição Permanente , Feminino , Humanos , Incisivo/patologia , Índia/epidemiologia , Masculino , Dente Molar/patologia , Prevalência , Índice de Gravidade de Doença
17.
Indian J Pathol Microbiol ; 58(2): 217-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25885138

RESUMO

Mitral valve prolapse (MVP) is usually asymptomatic, but can be associated with complications such as infective endocarditis, mitral regurgitation, thromboembolism and sudden cardiac death. It has been very rarely reported to occur in association with other valvular involvement. A 55-year-old male patient was brought dead and at autopsy the mitral valve orifice was stenotic and the leaflets were enlarged, myxoid and bulging suggestive of MVP and chordae tendinae were thickened, stretched and elongated. Similar changes were seen in the tricuspid valve. The pulmonary and aortic valves also showed myxomatous degeneration of their cusps. Myxomatous degeneration is the most common cause of MVP and it can be associated with involvement of the other valves. Concomitant involvement of the aortic valve has been reported, however it is very rare and simultaneous involvement of the pulmonary valve has not been reported in the literature so far. We report a case of MVP associated with myxomatous degeneration of the tricuspid, pulmonary and aortic valves.


Assuntos
Valva Aórtica/patologia , Prolapso da Valva Mitral/diagnóstico , Prolapso da Valva Mitral/patologia , Valva Mitral/patologia , Valva Pulmonar/patologia , Valva Tricúspide/patologia , Autopsia , Humanos , Masculino , Pessoa de Meia-Idade , Prolapso da Valva Mitral/complicações
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt B: 852-63, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25459608

RESUMO

In this present study, an organic compound Isonicotinic acid methyl ester (INAME) was structurally characterized by FTIR, FT-Raman, and NMR and UV spectroscopy. The optimized geometrical parameters and energies of all different and possible conformers of INAME are obtained from Density Functional Theory (DFT) by B3LYP/6-311++G(d,p) method. There are three conformers (SI, SII-1, and SII-2) for this molecule (ground state). The most stable conformer of INAME is SI conformer. The molecular geometry and vibrational frequencies of INAME in the ground state have been calculated by using HF and density functional method (B3LYP) 6-311++G (d,p) basis set. Detailed vibrational spectral analysis has been carried out and assignments of the observed fundamental bands have been proposed on the basis of peak positions and relative intensities. The computed vibrational frequencies were compared with the experimental frequencies, which yield good agreement between observed and calculated frequencies. A study on the electronic properties, such as HOMO and LUMO energies were performed by time independent DFT approach. Besides, molecular electrostatic potential (MEP) and thermodynamic properties were performed. The electric dipole moment (µ) and first hyper polarizability (ß) values of the investigated molecule were computed using ab initio quantum mechanical calculations. The calculated results show that the INAME molecule may have microscopic nonlinear optical (NLO) behavior with non zero values. The (1)H and (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by gauge independent atomic orbital (GIAO) method.


Assuntos
Ácidos Isonicotínicos/química , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Clorofórmio/química , Simulação por Computador , Dimetil Sulfóxido/química , Elétrons , Isomerismo , Conformação Molecular , Dinâmica não Linear , Espectroscopia de Prótons por Ressonância Magnética , Solventes/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termodinâmica , Vibração
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 138: 900-12, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25459692

RESUMO

In this work, the vibrational spectral analysis was carried out by using Raman and infrared spectroscopy in the range 100-4000cm(-1)and 50-4000cm(-1), respectively, for 2,2,4-Trimethyl Pentane, TMP (C8H18) molecule. The molecular structure, fundamental vibrational frequencies and intensity of the vibrational bands are interpreted with the aid of structure optimizations and geometrical parameter calculations based on Hartree Fock (HF) and density functional theory (DFT) method with 6-311++G(d,p) basis set. The scaled B3LYP/6-311++G(d,p) results shows the best agreement with the experimental values over the other method. The calculated HOMO and LUMO energies shows that charge transfer within the molecule. The physical reactions of single bond hydrocarbon TMP were investigated. The results of the calculations were applied to simulate spectra of the title compound, which shows the excellent agreement with observed spectra. Besides, Mulliken atomic charges, UV, frontier molecular orbital (FMO), MEP, NLO activity, Natural Bond-Orbital (NBO) analysis, NMR and thermodynamic properties of title molecule were also performed.


Assuntos
Elétrons , Modelos Moleculares , Octanos/química , Teoria Quântica , Análise Espectral Raman , Vibração , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Eletricidade , Conformação Molecular , Dinâmica não Linear , Fenômenos Ópticos , Espectroscopia de Prótons por Ressonância Magnética , Solventes/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termodinâmica
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