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1.
J Electron Mater ; 51(10): 5482-5491, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935037

RESUMO

We report herein the synthesis of ZnFe2O4 (ZF) nanoparticles via a simple and eco-friendly green route using lemon juice as a reducing agent and fuel. The effect of different calcination temperatures on the particle size and bandgap of grown ZF nanoparticles was investigated. The structural, morphological and optical properties of the synthesized nanoparticles were evaluated using synchrotron x-ray diffraction (S-XRD), field emission scanning electron microscopy (FE-SEM) and UV-visible diffuse reflectance spectroscopy (UV-Vis-DRS), respectively. S-XRD confirmed a spinel F-d3m phase in all four samples calcined at 350°C, 550°C, 750°C and 1000°C. The crystallite size calculated from the Debye-Scherrer equation showed an increase from 14 nm to 20 nm with the increase in calcination temperature. Williamson-Hall (W-H) analysis revealed an increase in the particle size from 16 nm to 21 nm and a decrease in the lattice microstrain from 0.913 × 10-3 to 0.154 × 10-4 with the increase in calcination temperature. The optical bandgap of the ZF nanoparticles obtained from UV-Vis-DRS decreased from 2.265 eV to 2.225 eV with the increase in calcination temperature. The ZF nanoparticles with tunable particle size, lattice microstrain and optical bandgap have potential application in ferrofluid, electromagnetic shielding, photocatalysis, hyperthermia, dye degradation and other areas. Supplementary Information: The online version contains supplementary material available at 10.1007/s11664-022-09813-2.

2.
J Laryngol Otol ; 136(8): 765-768, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35550682

RESUMO

BACKGROUND: The aggressiveness of paediatric cholesteatoma has long been a matter of debate. While much of the evidence is substantiated by data from the Western world, it is further limited by the retrospective nature of most studies. Therefore, this paper presents a comparative analysis of various characteristics of cholesteatoma between paediatric and adult populations seen at our centre. METHODS: A total of 50 patients (25 adults and 25 paediatric) with clinical diagnosis of chronic suppurative otitis media with cholesteatoma underwent canal wall down mastoidectomy over a period of two years. The intra-operative findings were noted and patients were followed up for six months. RESULTS: There was more extensive spread and ossicular erosion in paediatric cases. However, complications such as facial canal dehiscence and lateral semicircular canal dehiscence were more common in adults. CONCLUSION: Paediatric cholesteatoma is more aggressive and invasive than adult cholesteatoma, and the clinical behaviour is consistent with findings from other parts of the world.


Assuntos
Colesteatoma da Orelha Média , Colesteatoma , Otite Média Supurativa , Otite Média , Adulto , Criança , Colesteatoma/cirurgia , Colesteatoma da Orelha Média/complicações , Colesteatoma da Orelha Média/cirurgia , Doença Crônica , Humanos , Processo Mastoide/cirurgia , Mastoidectomia/efeitos adversos , Otite Média/cirurgia , Otite Média Supurativa/cirurgia , Estudos Retrospectivos
3.
J Anaesthesiol Clin Pharmacol ; 37(3): 469-474, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34759564

RESUMO

BACKGROUND AND AIMS: To evaluate the role of experience in acquisition of skill of orotracheal intubation in adults. MATERIAL AND METHODS: A prospective randomized study was conducted on 307 patients of either sex, belonging to ASA grade I and II (aged 18-60 years) posted for surgery under general anaesthesia. The patients were subjected to DL and ETI procedure, which was performed by five different groups of participants. Group 1 consisted of first-year resident of anaesthesiology with experience of less than 10 intubations, group 2 for second-year resident, group 3 for third-year resident, group 4 for senior resident and group 5 for consultant. Ease of mask ventilation, time taken for intubation, number of attempts, success rate, and ease of intubation were assessed for all the groups. RESULTS: Categorical variables were analysed using Chi-square test. For all statistical tests, a P value less than 0.05 was taken as a significant difference. Maximum difficulty in mask ventilation was encountered by group 1 anaesthesiologist, that is, in 69.2% of the patients. Group 1 took maximum time to intubate, that is, 47.98 ± 31.54 sec and least time was taken by group 5 anaesthesiologist (9.55 ± 6.93) sec. First attempt success rate was least in group (80.0%). Group 1 had success rate of 96.9%, whereas rest all groups had 100% success. CONCLUSION: Skill of mask ventilation and intubation and time taken for intubation grossly improves with increasing experience. Minimum of 25 intubation attempts should be required by an anaesthesiologist resident in elective scenario to achieve 100% success rate in our study.

5.
6.
Indian J Surg ; 77(Suppl 3): 945-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27011488

RESUMO

Parotidectomy surgeries are being routinely performed by ENT surgeons nowadays. Parotid tumours can present with a variety of manifestations ranging from a barely noticeable mass to a large tumour with facial paralysis. Most benign parotid tumours are located in the superficial lobe though rarely deep lobe may also be involved, while malignant tumours are generally seen to involve both the lobes of the gland. We present clinico-radiological-pathological profile of 25 patients who underwent parotid surgeries for tumours involving deep lobe alone or the whole gland, and were operated at our institute during the period from January 2011 to December 2012. This study was a retroprospective observational analysis with the aim of analyzing the epidemiology, radiological, surgical and histopathological profile of these patients. Among 25 patients who underwent parotid surgeries, 17 patients underwent total conservative parotidectomy, while 5 patients underwent radical parotidectomy. In 3 patients, extended radical parotidectomy was performed. We also report the complications and follow-up of these patients. We concluded that fine needle aspiration cytology (FNAC) findings and final histopathological report may not always correlate.

7.
Ann Oncol ; 24(2): 377-384, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23028037

RESUMO

BACKGROUND: The prognostic value of histologic grade (HG) in invasive lobular carcinoma (ILC) remains uncertain, and most ILC tumors are graded as HG2. Genomic grade (GG) is a 97-gene signature that improves the prognostic value of HG. This study evaluates whether GG may overcome the limitations of HG in ILC. METHODS: Gene expression data were generated from frozen tumor samples, and GG calculated according to the expression of 97 genes. The prognostic value of GG was assessed in a stratified Cox regression model for invasive disease-free survival (IDFS) and overall survival (OS). RESULTS: A total of 166 patients were classified by GG. HG classified 33 (20%) tumors as HG1, 120 (73%) as HG2 and 12 (7%) as HG3. GG classified 106 (64%) tumors as GG low (GG1), 29 (17%) as GG high (GG3) and 31 (19%) as equivocal (cases not classified as GG1 or GG3). The median follow-up time was 6.5 years. In multivariate analyses, GG was associated with IDFS [HR(GG3 vs GG1) 5.6 (2.1-15.3); P < 0.001] and OS [HR(GG3 vs GG1) 7.2, 95% CI (1.6-32.2); P = 0.01]. CONCLUSIONS: GG outperformed HG in ILC and added prognostic value to classic clinicopathologic variables, including nodal status.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Carcinoma Lobular/genética , Carcinoma Lobular/mortalidade , Neoplasias da Mama/patologia , Carcinoma Lobular/patologia , Intervalo Livre de Doença , Feminino , Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Prognóstico , Modelos de Riscos Proporcionais , Receptor ErbB-2/metabolismo , Análise de Sobrevida , Análise Serial de Tecidos , Transcriptoma
8.
Indian J Med Sci ; 64(10): 468-75, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23023308

RESUMO

BACKGROUND: Laryngoscopy and endotracheal intubation are known to cause increase in both arterial blood pressure and heart rate. Several strategies have been evolved to blunt the haemodynamic response to tracheal intubation but each method has its own advantages and disadvantages. Esmolol, a cardio selective Beta-1 blocking drug, can alleviate some of these problems. Esmolol, when administered parenterally, exhibits rapid onset and a short duration of action due to its rapid clearance by red blood cell esterases. Hence we conducted the present study to evaluate the efficacy and optimum time of single bolus esmolol administration in attenuating hypertensive- tachycardiac response to laryngoscopy and tracheal intubation. MATERIALS AND METHODS: The randomized double blind prospective study was conducted in 60 patients, in the age group of 20-40 years, of both sexes, belonging to American Society of Anaesthesiologists (ASA) physical status class I or II and scheduled for elective surgery requiring endotracheal intubation and general anaesthesia. The efficacy and optimum time of single bolus esmolol administration in attenuating hypertensive - tachycardiac response to laryngoscopy and tracheal intubation was evaluated. Patients in group I (n = 20) received bolus administration of injection esmolol 1.5 mg/kg intravenously (iv) 90 seconds before intubation; in group II (n = 20) three minutes before intubation and in group III (n = 20) six minutes before intubation. RESULTS: There was no clinical and statistically significant variation in heart rate in group I and II at different time intervals of the study period but in group III heart rate increased significantly one minute after tracheal intubation. (P < 0.05) One minute after intubation, the increase in systolic, diastolic and mean blood pressure and rate pressure product was statistically significant in group I (P < 0.01) and group III. (P < 0.05) However, in group II increase in systolic blood pressure and rate pressure product was statistically not significant. (P > 0.05) CONCLUSION: To conclude, single intravenous bolus dose of esmolol (1.5 mg/kg) is safe and more effective in attenuating haemodynamic response to laryngoscopy and tracheal intubation when administered three minutes prior to intubation.


Assuntos
Hemodinâmica/efeitos dos fármacos , Intubação Intratraqueal/métodos , Propanolaminas/administração & dosagem , Antagonistas de Receptores Adrenérgicos beta 1/administração & dosagem , Adulto , Anestesia Geral/métodos , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Injeções Intravenosas , Laringoscopia , Masculino , Estudos Prospectivos , Adulto Jovem
10.
J Nanosci Nanotechnol ; 8(7): 3526-31, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19051906

RESUMO

Formations of Y and T nano junctions have been observed in boron nitride films deposited on silicon substrates by plasma chemical reaction of diborane (B2H6 diluted in hydrogen) and ammonia (NH3) gases using dual frequency (microwave/radio) plasma enhanced chemical vapor deposition technique without any intentional heating of the substrates. It has been observed that these nano junctions form at a critical feed gas ratio of ammonia and diborane. We have investigated the effect of gas feed ratio R (=NH3/B2H6) in the plasma reaction chamber, keeping all other deposition parameters constant, on the morphology of boron nitride films. The deposited films are characterized by SEM, AFM, TEM and Laser Raman. For gas feed ratio, R < 100, octahedron and cubic morphologies have been observed in BN films and on increasing R to >100, size of the crystallites reduces to nanometer level. In some of our BN samples deposited at a critical value of gas ratio (R = 400), uniform Y and T junctions having bamboo like morphologies, in nanometer level, have been observed, which we wish to emphasis here as an interesting and newer observation in boron nitride films deposited by the dual frequency PECVD technique. This change in morphology exhibited by varying gas feed ratio is mainly due to excess nitrogen ions in the plasma.

14.
J Pharm Biomed Anal ; 25(1): 9-14, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11274853

RESUMO

The suitability of the United States Pharmacopeia (USP) assay method for analysing stressed samples of cyclosporine oral solution USP was evaluated for stability samples by analyzing cyclosporine oral solution after acid, alkali, hydrogen peroxide, heat and light treatment. Some of the degradants generated during stress testing, as well as dihydrocyclosporine A, which is a known degradant of cyclosporine A, were not adequately resolved from the cyclosporine peak and mobile phase adjustments did not improve the resolution. In addition, isocyclosporine A, another known degradant of cyclosporine, could not be quantitated as it was eluting too early with the system peaks. Therefore, a binary gradient, reverse phase, stability indicating, HPLC method for the assay of cyclosporine in cyclosporine oral solution USP has been developed and validated. Analysis of degraded samples showed that the cyclosporine A eluted as a spectrally pure peak resolved from its degradation products.


Assuntos
Antirreumáticos/análise , Cromatografia Líquida de Alta Pressão/métodos , Ciclosporina/análise , Administração Oral , Controle de Qualidade , Reprodutibilidade dos Testes , Soluções
15.
Anticancer Res ; 20(1A): 183-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10769653

RESUMO

BACKGROUND: Reptimed is a novel, species-conserved, bone marrow-derived molecule which possesses anti-neoplastic activity. Previously, we established an orthotopic murine bladder tumor (MBT-2) model and reported accurate documentation of the presence and the extent of intravesical involvement of bladder tumor implants using magnetic resonance imaging (MRI) (1). Herein, we investigated the activity of exogenously administered Reptimed in the MBT-2 model. MATERIALS AND METHODS: Intravesicular and intraperitoneal administration of Reptimed concurrently with and following transurethral tumor cell implantation was performed and MBT-2 tumor response was assessed at several time points post tumor implant. RESULTS: Serial MRI scans of Reptimed-treated mice at days 14 to 33 post tumor transplant revealed significant inhibition of bladder tumor growth with no significant tumor growth observed by MRI on day 33 post-implant. The corresponding histological examination of the whole mount bladder sections revealed similar inhibitory effects of Reptimed with respect to the topography and depth of intravesical tumor involvement. In contrast, control, untreated bladders revealed extensive exophytic tumors with deeply invasive transitional cell carcinoma. CONCLUSIONS: These studies demonstrate the anti-tumor effect of Reptimed and highlight its importance as a potential therapy for cancer.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células de Transição/prevenção & controle , Inibidores do Crescimento/uso terapêutico , Polissacarídeos/uso terapêutico , Neoplasias da Bexiga Urinária/prevenção & controle , Administração Intravesical , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Medula Óssea/química , Carcinoma de Células de Transição/induzido quimicamente , Carcinoma de Células de Transição/patologia , Divisão Celular/efeitos dos fármacos , FANFT , Feminino , Inibidores do Crescimento/administração & dosagem , Inibidores do Crescimento/isolamento & purificação , Inibidores do Crescimento/farmacologia , Células-Tronco Hematopoéticas/química , Injeções Intraperitoneais , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C3H , Invasividade Neoplásica , Transplante de Neoplasias , Polissacarídeos/administração & dosagem , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Ratos , Ratos Endogâmicos WF , Transplante Heterotópico , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/patologia
16.
Am J Otolaryngol ; 20(2): 102-5, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10203160

RESUMO

PURPOSE: The aim of this study was to determine the relationship of HLA typing in patients with otosclerosis. MATERIALS AND METHODS: We used a prospective study in which HLA typing of 100 surgically confirmed otosclerosis patients were compared with age and sex matched normal individuals. RESULTS: HLA-A3, HLA-A9, HLA-A11, and HLA-B13 were found to be significantly higher (P < .05, .01, and .01, respectively). HLA-A9 and HLA-A11 were found to be higher (P < .01) in patients with a positive family history, indicating genetic heterogenicity. CONCLUSIONS: Higher values of HLA-A9, HLA-11, and HLA-B13 in patients with otosclerosis compared with normal individuals strongly suggests a genetic, HLA-related component.


Assuntos
Antígenos HLA/genética , Otosclerose/genética , Adolescente , Adulto , Epitopos , Feminino , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
17.
18.
Aust N Z J Obstet Gynaecol ; 38(3): 327-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9761165

RESUMO

Uterus didelphys is a rare congenital anomaly. It can result in a variety of misadventures even in the hands of an expert. The present case reports uterus didelphys as the cause for tubal sterilization failure. This is the first case of this type seen in our institution in 35 years.


Assuntos
Esterilização Tubária , Útero/anormalidades , Adulto , Colo do Útero/anormalidades , Feminino , Humanos , Gravidez , Falha de Tratamento
19.
J Immunol ; 161(4): 1930-8, 1998 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9712063

RESUMO

The expression of the seven-transmembrane domain chemokine receptors CXCR1 and CXCR2 modulates neutrophil responsiveness to the chemoattractant IL-8 and a number of closely related CXC chemokines. In the present study, we investigated the mechanism by which bacterial LPS induces the down-modulation of IL-8 responsiveness and CXCR1 and CXCR2 expression on human neutrophils. Treating neutrophils with LPS reduced IL-8R expression to 55 +/- 5% of the control within 30 min and to 23 +/- 2% within 1 h of stimulation. Furthermore, this down-modulation could not be attributed to increased concentrations of IL-8, TNF-alpha, or IL-1beta, since ELISA studies indicated that LPS-stimulated neutrophils did not release detectable amounts of these proteins before 2 h poststimulation. The tyrosine kinase (TK) inhibitors genistein and herbimycin A attenuated the LPS-mediated down-modulation of CXCR1 and CXCR2, indicating that the activation of a TK is required for LPS to mediate its effect. The effect of LPS on receptor expression paralleled the hyperphosphorylation of the protein TK p72syk. Although IL-8 induced a comparable down-modulation of CXCR1 and CXCR2, TK inhibitors did not attenuate this effect. These studies provide the first evidence of an agonist-independent, TK-dependent pathway of chemokine receptor regulation by endotoxin.


Assuntos
Antígenos CD/metabolismo , Regulação para Baixo/imunologia , Interleucina-8/metabolismo , Lipopolissacarídeos/farmacologia , Neutrófilos/metabolismo , Proteínas Tirosina Quinases/fisiologia , Receptores de Quimiocinas/metabolismo , Receptores de Interleucina/metabolismo , Antígenos CD/biossíntese , Antígenos CD/química , Benzoquinonas , Regulação para Baixo/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Precursores Enzimáticos/metabolismo , Proteínas de Ligação ao GTP/fisiologia , Genisteína/farmacologia , Humanos , Interleucina-1/metabolismo , Interleucina-8/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular , Lactamas Macrocíclicas , Peso Molecular , Ativação de Neutrófilo/imunologia , Neutrófilos/enzimologia , Fosforilação , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Quinonas/farmacologia , Receptores de Quimiocinas/agonistas , Receptores de Quimiocinas/biossíntese , Receptores de Interleucina/agonistas , Receptores de Interleucina/biossíntese , Receptores de Interleucina/química , Receptores de Interleucina-8A , Receptores de Interleucina-8B , Rifabutina/análogos & derivados , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Quinase Syk , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , Tirosina/metabolismo
20.
Aust N Z J Obstet Gynaecol ; 38(2): 227-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9653869

RESUMO

Bladder exstrophy is an unusual congenital anomaly. Patients becoming pregnant with such anomaly after surgical repair are even rarer. The present case reports a lower segment Caesarean section delivery of a living healthy baby in a woman who had been operated on for bladder exstrophy at the age of 18 years. This is the first case of this type seen in our institution in 35 years.


Assuntos
Extrofia Vesical/cirurgia , Cesárea , Complicações do Trabalho de Parto/cirurgia , Complicações Pós-Operatórias/cirurgia , Adulto , Extrofia Vesical/diagnóstico por imagem , Apresentação Pélvica , Cistectomia , Feminino , Humanos , Recém-Nascido , Complicações do Trabalho de Parto/diagnóstico por imagem , Equipe de Assistência ao Paciente , Complicações Pós-Operatórias/diagnóstico por imagem , Gravidez , Radiografia , Derivação Urinária
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