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1.
J Fluoresc ; 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37589935

RESUMO

In this study, the photophysical properties of oxazole derivatives such as 5-(furan-2-yl) -4-tosyloxazole (OX-1) and 5-(2-bromothiazol-4-yl)-4-tosyloxazoles (OX-2) were investigated using theoretical and experimental techniques. The ground and excited state dipole moments were empirically obtained utilising the solvatochromic shift technique and several solvatochromic correlations such as Lippert's, Bakhshiev's, KawskiChamma- Viallet's, and solvent polarity equations. The ground state dipole moments, HOMO-LUMO and molecule electrostatic potential map were also computed using ab initio calculations and evaluated using Gaussian 09 W software. Furthermore, spectroscopic interactions between newly synthesised dyes (OX-1 and OX-2) and freshly synthesised silver nanoparticles (size 40 nm) were studied. Increased absorbance and widening of absorption spectra for both dyes in the presence of varied quantities of silver nanoparticles show the potential of dye-nanoparticle interactions. Fluorescence quenching has been detected for both dyes in the presence of colloidal silver nanoparticles, indicating dynamic quenching, and a significant overlap between the absorption and emission spectra of the silver nanoparticle reveals that fluorescence quenching is also due to energy transfer.

2.
Br J Oral Maxillofac Surg ; 59(3): 281-285, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33581884

RESUMO

In spite of the development of modern injection techniques, palatal injection is still a painful experience for patients. A plethora of techniques has been tested to reduce this. One such technique that has been claimed to work is administering articaine on the buccal side alone for the extraction of maxillary teeth due to its ability to diffuse through soft and hard tissues more reliably than other local anaesthetics. This split mouth study evaluated the efficacy of 4% articaine with 1:100000 adrenaline to avoid the painful palatal injection for bilateral permanent maxillary tooth extraction in 50 patients. The 100mm 10 point Visual Analog Scale/Wong Baker Facial Pain Scale was used to rate the amount of pain felt on injection, on probing the tissues prior to, or during, extraction, and one hour postoperatively. Although the buccal injection alone resulted in lower pain while injecting the anaesthetic, it did not result in the absence of pain before tooth extraction as has been suggested by various studies. A total of 74% patients required a palatal injection on the study side. We conclude that in most cases, when using a buccal injection alone, one cannot rely on the diffusion of articaine for effective palatal anaesthesia. Despite this, we suggest that as an initial option in young patients, the operator can consider avoiding the painful palatal injection by the use of articaine to prevent aversion to dental treatment. Postoperatively, the difference in pain levels was not statistically significant and no patient showed signs of lesions at the injection sites.


Assuntos
Anestesia Dentária , Carticaína , Anestesia Local , Anestésicos Locais , Humanos , Lidocaína
3.
Ultrason Sonochem ; 39: 153-159, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28732932

RESUMO

The present work establishes in depth study of ultrasound assisted preparation of performic acid (PFA) in a continuous flow microstructured reactor. The influence of various parameters viz. formic acid: hydrogen peroxide molar ratio, flow rate, temperature and catalyst loading on the PFA formation were studied in a continuous flow microstructured reactor. In a continuous microstructured reactor in the presence of ultrasonic irradiation, the formation of PFA was found to be dependent on the molar ratio of formic acid: hydrogen peroxide, flow rate of reactants, temperature and catalyst loading (Amberlite IR-120H). The optimized parameter values are 1:1M ratio, 50mL/h, 40°C and 471mg/cm3 respectively. Further, the performance of Amberlite IR-120H catalyst was evaluated for three successive cycles in continuous microstructured reactor. The performance of catalyst was found to be decreased with the usage of the catalyst and is attributed to neutralization of the sulfonic acid groups, catalyst shrinkage, or loss in pore sites. The experimental results revealed that, for an ultrasound assisted synthesis of PFA in continuous microstructured reactor the observed reaction time was even less than 10min. The observed intensification in the PFA synthesis process can be attributed to the intense collapse of the cavities formed at low temperature during ultrasonic irradiations, which further improved the heat and mass transfer rates with the formation of H2O2 during the reaction. The combined use of ultrasound and a continuous flow microstructured reactor has proved beneficial process of performic acid synthesis.

4.
J Environ Sci Eng ; 55(2): 253-66, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25464702

RESUMO

Pickling is the process of removal of oxide layer and rust formed on metal surface. It also removes sand and corrosion products from the surface of metal. Acids such as sulfuric acid, hydrochloric acid are used for pickling. Hydrofluoric acid-Nitric acid mixture is used for stainless steel pickling. Pickling solutions are spent when acid concentration in pickling solutions decreases by 75-85%, which also has metal content up to 150-250 g/ dm3. Spent pickling liquor (SPL) should be dumped because the efficiency of pickling decreases with increasing content of dissolved metal in the bath. The SPL content depends on the plant of origin and the pickling method applied there. SPL from steel pickling in hot-dip galvanizing plants contains zinc(II), iron, traces of lead, chromium. and other heavy metals (max. 500 mg/dm3) and hydrochloric acid. Zinc(II) passes tothe spent solution after dissolution of this metal from zinc(II)-covered racks, chains and baskets used for transportation of galvanized elements. Unevenly covered zinc layers are usually removed in another pickling bath. Due to this, zinc(II) concentration increases even up to 110 g/dm3, while iron content may reach or exceed even 80 g/dm3 in the same solution. This review presents an overview on different aspects of generation and treatment of SPL with recourse to recovery of acid for recycling. Different processes are described in this review and higher weightage is given to membrane processes.


Assuntos
Ácidos/isolamento & purificação , Resíduos Industriais , Metalurgia/métodos , Gerenciamento de Resíduos/métodos , Aço
5.
J Colloid Interface Sci ; 358(1): 238-44, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21453926

RESUMO

Nearly monodisperse rhodium nanoparticles with adsorbed NH(x) were synthesized at the CCl(4)-water interface. The presence of NH(x)-adsorbed species was confirmed by energy-dispersive X-ray analysis (EDX) and X-ray photoelectron spectroscopy (XPS) studies. The synthesis of controlled size 2-38 nm rhodium particles was studied as a function of reducing agent concentration by transmission electron microscopy (TEM). HRTEM confirmed the formation of rhodium nanoparticles having fringe spacing consistent with reported Rh (111) planes. The continuity of these films over an area of 1×1 µm was revealed by atomic force microscopy (AFM) studies. The electrocatalytic application of these nanostructure Rh-NH(x) thin films for formaldehyde oxidation in 0.5M NaOH was investigated by cyclic voltammetry. The Rh nanoparticles formed by the present strategy are expected to be useful for other catalytic applications also.


Assuntos
Nanopartículas/química , Nanotecnologia/métodos , Ródio/química , Adsorção , Catálise , Eletroquímica , Nanopartículas/ultraestrutura , Nanotecnologia/economia , Oxirredução , Propriedades de Superfície , Água/química
6.
Oral Dis ; 16(1): 29-33, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19656315

RESUMO

BACKGROUND AND OBJECTIVE: Increased oxidative and nitrosative stress associated with disturbances in antioxidant defense system have been implicated in the pathogenesis of several diseases, most notably oral cancer. The aim of this study was to evaluate the oxidant-antioxidant status in blood samples and tumor tissue in oral squamous cell carcinoma (OSCC) patients in comparison with the healthy controls. METHODS: Blood and tumor tissue samples from the diseased individuals and the normal controls were analyzed for malondialdehyde (MDA) and nitric oxide (NO) as indicators of oxidative stress and nitrosative stress respectively; superoxide dismutase (SOD) and catalase enzymes as indicators of antioxidant defense by UV visible spectrophotometer. RESULTS: Malondialdehyde and NO levels were significantly elevated in the blood and tissue samples of OSCC patients as compared with the healthy controls. The antioxidant enzymes SOD and catalase were significantly reduced in tissue samples of OSCC group than in the control group while in the erythrocytes, catalase levels were significantly reduced and the SOD levels were higher in OSCC group in comparison with the healthy controls. INTERPRETATION AND CONCLUSION: Increased levels of MDA and NO indicate an increase in the oxidative stress in OSCC patients associated with a deficient antioxidant defense mechanism. This oxidant-antioxidant imbalance may be considered as one of the factors responsible for pathogenesis of cancer. Future studies regarding assessment of oxidant-antioxidant status in OSCC patients in view of selecting appropriate mode of therapy and the effectiveness of such therapy in limiting the tumor progression and recurrence is to be carried out.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Malondialdeído/metabolismo , Neoplasias Bucais/metabolismo , Óxido Nítrico/metabolismo , Carcinoma de Células Escamosas/sangue , Estudos de Casos e Controles , Catalase/sangue , Catalase/metabolismo , Feminino , Humanos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Neoplasias Bucais/sangue , Óxido Nítrico/sangue , Nitrosação , Estresse Oxidativo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Espectrofotometria , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo
7.
Indian J Plast Surg ; 42(1): 122-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19881034

RESUMO

A case of lipofibromatous hamartoma of the median nerve in an adult is described in this article. A 33-year-old male presented with tingling, numbness and swelling in the palm of the left non dominant hand that had been present for a few months. Examination revealed that there was fullness in the volar aspect of the wrist and in the inter-thenar area. Another mass was present at the base of the index finger, which appeared to be involving subcutaneous tissues. The clinical diagnosis was carpal tunnel syndrome due to a space occupying tumor mass in the carpal tunnel. On exploration of the carpal tunnel, a large median nerve was seen 4 cm proximal to the wrist crease line and extending distally until it divided into its branches. Another mass was present at the base of the index finger, which was adherent to the skin. The radial digital nerve of the index finger was normal in size. For the enlarged nerve, an epineurotomy was performed and a biopsy was taken. Another biopsy was taken from the distal mass. His postoperative period was uneventful. In July 2004, at the end of 5 years, the patient had no symptoms and the size of the tumor had not increased.

8.
Clin Rheumatol ; 26(12): 2185-2187, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17628740

RESUMO

We encountered only three patients of carpal tunnel syndrome (CTS) due to tophaceous gout during 25 years of practice in a 'hand clinic' situated in a large metropolis in West India. In two patients, the CTS was bilateral, a rare occurrence in gout. There was an unwarranted delay (up to 9 years) in the diagnosis of both the ailments. In each case, the site of offending tophus was uniquely different.


Assuntos
Síndrome do Túnel Carpal/complicações , Gota/complicações , Adulto , Idoso , Alopurinol/uso terapêutico , Síndrome do Túnel Carpal/diagnóstico , Síndrome do Túnel Carpal/tratamento farmacológico , Diagnóstico Diferencial , Quimioterapia Combinada , Seguimentos , Glucocorticoides/uso terapêutico , Gota/diagnóstico , Gota/tratamento farmacológico , Supressores da Gota/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Prednisolona/uso terapêutico
9.
J Mol Endocrinol ; 35(2): 357-72, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16216915

RESUMO

Acquisition of functional receptivity by the endometrium is assumed to be effected by progesterone-dependent expression and repression of several genes during the implantation window in a menstrual cycle. In the present study, we employed differential display (DD) reverse transcription-polymerase chain reaction (RT-PCR) to identify progesterone-dependent gene/gene fragments that are differentially expressed during the peri-implantation phase in receptive and nonreceptive endometria, obtained from fertile and infertile bonnet monkeys respectively. Receptive endometria were obtained from regularly cycling (n=5) fertile female bonnet monkeys. Endometrial nonreceptivity was induced by treating bonnet monkeys with either 2.5 mg (n=5) or 5.0 mg (n=5) onapristone (ZK 98.299), an antiprogestin, on every third day for one cycle. Ovulation, levels of circulatory hormones (estradiol and progesterone) and menstrual cycle length did not change in treated animals; however, endometrial growth was retarded. DD2, one of the differentially expressed cDNA fragments, showed higher representation in nonreceptive endometria than in receptive endometria. The DD2 sequence was found to be homologous to the sequence of the carboxyl terminal region of Rab coupling protein (RCP), a recently discovered protein involved in intracellular vesicular trafficking. To confirm the identity of DD2 as RCP, RT-PCR studies were carried out with a forward primer deduced from the RCP sequence and a reverse primer from the DD2 sequence. The product (DDRCP) obtained, when sequenced, revealed 95% homology with the nucleotide number 1196-1757 of human RCP cDNA. Furthermore, the pattern of DDRCP expression at transcript level was found to be similar to that shown by DD2; that is, it was higher in nonreceptive endometrium. Northern analysis using labeled DD2 or DDRCP cDNA fragments identified two transcripts of 6.0 and 4.0 kb in human endometrium. In situ hybridization studies using digoxigenin-labeled DD2 revealed significantly higher (P < 0.05) localization of endometrial RCP transcripts in the proliferative phase than in the peri-implantation phase in control animals. The localization was also significantly (P < 0.01) higher in peri-implantation-phase endometria from antiprogestin-treated animals than in control animals. These antiprogestin-treated animals, however, did not demonstrate any concomitant increase in the levels of immunoreactive endometrial Rab4 and Rab11 during the peri-implantation phase. A similar pattern of cycle-dependent RCP expression was observed in human endometrial biopsies. Furthermore, significantly higher (P < 0.05) levels of RCP transcripts were detected during the peri-implantation phase in women with unexplained infertility (n=3) than in fertile women (n=3). This is the first report indicating the endometrial expression of RCP and its hormonal regulation.


Assuntos
Proteínas de Transporte/metabolismo , Endométrio/metabolismo , Macaca radiata , Proteínas de Membrana/metabolismo , Progesterona/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/genética , Endométrio/citologia , Feminino , Perfilação da Expressão Gênica , Humanos , Hibridização In Situ , Proteínas de Membrana/genética , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Alinhamento de Sequência , Técnicas de Cultura de Tecidos , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab4 de Ligação ao GTP/genética , Proteínas rab4 de Ligação ao GTP/metabolismo
10.
Poult Sci ; 82(4): 571-6, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12710475

RESUMO

A study was conducted to determine the efficacy of esterified glucomannan in counteracting the toxic effects of mycotoxins in naturally contaminated diet (aflatoxin 168 ppb, ochratoxin 8.4 ppb, zearalenone 54 ppb, and T-2 toxin 32 ppb) fed to commercial broilers. One-day-old broiler chicks were randomly assigned to one of the four dietary treatments with five replicates of 14 chicks each. Four dietary treatments were 1) control; 2) esterified glucomannan, an adsorbent, tested at 0.05% of diet; 3) naturally contaminated diet; and 4) esterified glucomannan (0.05%) plus naturally contaminated diet. Body weight, feed consumption, feed efficiency, hematology, and serum biochemical and enzyme activities were evaluated. Compared with the control, the naturally contaminated diet significantly decreased body weight and feed consumption and resulted in poor feed efficiency. Esterified glucomannan effectively alleviated the growth depression caused by the naturally contaminated diet. Increased relative weights of liver and gizzard were observed in chicks fed the naturally contaminated diet. Further, feeding a naturally contaminated diet was associated with significant decreases in urea nitrogen and hematocrit values along with altered gamma-glutamyl transferase activity; however, urea nitrogen concentration was improved with addition of esterified glucomannan. These findings suggest that addition of dietary esterified glucomannan is effective in counteracting the toxic effects of naturally contaminated feed with mycotoxins.


Assuntos
Galinhas/crescimento & desenvolvimento , Contaminação de Alimentos , Mananas/farmacologia , Micotoxicose/veterinária , Doenças das Aves Domésticas/prevenção & controle , Ração Animal , Animais , Nitrogênio da Ureia Sanguínea , Peso Corporal , Galinhas/sangue , Ingestão de Alimentos , Esterificação , Feminino , Hematócrito/veterinária , Masculino , Mananas/administração & dosagem , Mananas/química , Micotoxicose/prevenção & controle , Micotoxinas/toxicidade , Tamanho do Órgão , Distribuição Aleatória , gama-Glutamiltransferase/metabolismo
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