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1.
Indian J Otolaryngol Head Neck Surg ; 75(4): 3792-3797, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37974880

RESUMO

The focal point of thyroidectomy surgery has always been to reduce the incidence of inadvertent damage to the recurrent laryngeal nerve(RLN). The intracapsular thyroidectomy is one such technique with minimum chance of injuring the nerve. To compare retrospectively the surgical outcomes between the two methods of thyroidectomy-coventional thyroidectomy Vs intracapsular thyroidectomy. Materials and methods-55 cases of benign thyroid disease for whom thyroidectomy was performed in our hospital between the period of 2019-2022 were compared retrospectively. Out of these 34 cases had undergone intracapsular thyroidectomy and 21 cases underwent routine extracapsular thyroidectomy. The surgical outcomes including operation time, pain, postoperative infection, postoperative hypocalcemia, postoperative recurrent laryngeal nerve paralysis and mean hospital stay were analyzed. The mean operating time were very low in the intracapsular limb as compared to the other group. The pain and the mean hospital stay was also far lesser for the intracapsular limb. Both cohorts had no incidence of hypocalcemia. The incidence of recurrent laryngeal nerve palsy was very low in the intracapsular cohort (only 1 case of temporary unilateral RLN palsy), whereas it was higher in the routine extracapsular cohort (5 cases of permanent palsy). The risk of having vocal cord palsy (left/right) is 1.172 times more with conventional/standard thyroidectomy as compared to intracapsular thyroidectomy. Intracapsular technique is a much more rewarding method to perform thyroidectomy, without the risk of the recurrent laryngeal nerve palsy as compared to routine thyroidectomy.

2.
J Venom Res ; 11: 16-20, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34123360

RESUMO

Polistes stigma is a common social wasp found in continental Southeast Asia. Despite its wide distribution and abundance, hitherto, there are no studies on small or medium molecular weight components of the venom. For the first time, this study has described the amino acid sequences and its post-translation modifications (PTM's) of four wasp-mastoparans (Ps 1524, Ps 1540, Ps 1556 and Ps 1630), three chemotactic peptides (Ps1417, Ps1434 and Ps1474) and one more (Ps1549) lysine rich peptide from the venom of P. stigma. There were 27 mass traces obtained from the crude natural venom, in which the complete amino acid sequences of 8 peptides were solved. Further, single disulphide bonded peptides uncommon in wasp venoms were identified. The mastoparan peptides were rich in hydrophobic residues. In addition, the peptides Ps1549, Ps1630, Ps1434 and Ps1417 were found to have unusual PTM's of C-terminal amidation. This preliminary study comprehends the untapped compounds present in wasp venom that are equally valuable to widely studied venoms of snakes, spiders and cone snails.

3.
Artigo em Inglês | MEDLINE | ID: mdl-26027004

RESUMO

Single crystals of molybdenum-incorporated tris(thiourea)zinc(II) sulfate (MoZTS) are grown by the slow evaporation solution growth technique. Crystal composition as determined by single-crystal X-ray diffraction analysis reveals that it belongs to the orthorhombic system with space group Pca21 and cell parameters a = 11.153 (2), b = 7.7691 (14), c = 15.408 (3) Å, V = 1335.14 (4) Å(3) and Z = 4. The surface morphological changes are studied by scanning electron microscopy. The vibrational patterns in FT-IR are used to identify the functional group and TGA/DTA (thermogravimetric analysis/differential thermal analysis) indicates the stability of the material. The structure and the crystallinity of the material were confirmed by powder X-ray diffraction analysis and the simulated X-ray diffraction (XRD) closely matches the experimental one with varied intensity patterns. The band gap energy is estimated using diffuse reflectance data by the application of the Kubelka-Munk algorithm. The relative second harmonic generation (SHG) efficiency measurements reveal that MoZTS has an efficiency comparable to that of tris(thiourea)zinc(II) sulfate (ZTS). Hirshfeld surfaces were derived using single-crystal X-ray diffraction data. Investigation of the intermolecular interactions and crystal packing via Hirshfeld surface analysis reveal that the close contacts are associated with strong interactions. Intermolecular interactions as revealed by the fingerprint plot and close packing could be the possible reasons for facile charge transfer leading to SHG activity.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 140: 311-27, 2015 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-25615677

RESUMO

The synthesis of (1E,4E)-1,5-di-p-tolylpenta-1,4-dien-3-one (DTDO) was done and its single crystals were grown by slow evaporation solution technique from 4-methylbenzaldehyde, acetone solution at room temperature. Crystal structure is determined by single crystal X-ray diffraction analysis and reveals that it belongs to the monoclinic system with four molecules in the unit cell (space group C2). The emission of green light from the sample confirms the second harmonic generation (SHG) of the specimen responsible for nonlinear optical property. The various vibration patterns of the specimen have been investigated by Fourier transform infrared and Fourier transform Raman spectroscopy. Optimized molecular geometry, vibrational patterns of DTDO are derived from density functional theory (DFT) calculations and the results are compared with experimental one. The molecular stability and bond strengths were investigated by applying the natural bond orbital analysis. Information about the size, shape, charge density distribution and site of chemical reactivity of the molecule has been obtained by mapping electron density with molecular electrostatic potential (MEP). Highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy gaps were calculated. The other molecular properties like charge transfer are explained using Mulliken population analysis and the first-order molecular hyperpolarizability (ß) of the specimen is also estimated and SHG efficiency of DTDO was found to be 3.9 times that of KDP. Fingerprint plots and Hirshfeld surfaces were used to locate and analyze the molecular surface and bonding interactions in various methodologies utilized in the establishment of the relative energies.


Assuntos
Chalcona/química , Cristalografia por Raios X , Modelos Moleculares , Conformação Molecular , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
5.
Artigo em Inglês | MEDLINE | ID: mdl-25062048

RESUMO

Single crystals of 4-aminobenzophenonium picrate (4ABPP) were grown by slow evaporation of a mixed solvent system methanol-acetone (1:1,v/v) containing equimolar quantities of picric acid and 4-aminobenzophenone. The proton and carbon signals are confirmed by nuclear magnetic resonance spectroscopy. The various functional groups present in the molecule are identified by FT-IR analysis. Optimized geometry, first-order molecular hyperpolarizability (ß), polarizability (α), bond length, bond angles and excited state energy from theoretical UV were derived by Hartree-Fock calculations. The complete assignment of the vibrational modes for 4-aminobenzophenonium picrate was performed by the scaled quantum mechanics force field (SQMFF) methodology using potential energy distribution. Natural bond orbital (NBO) calculations were employed to study the stabilities arising from charge delocalization and intermolecular interactions of 4ABPP. The atomic charge distributions of the various atoms present in 4ABPP are obtained by Mulliken charge population analysis. The as-grown crystal is further characterized by thermal and optical absorbance studies.


Assuntos
Modelos Moleculares , Picratos/química , Picratos/síntese química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cristalização , Análise Diferencial Térmica , Elétrons , Cinética , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria
6.
Artigo em Inglês | MEDLINE | ID: mdl-25233030

RESUMO

The influence of Sr(II)-doping on the properties of tetrakis(thiourea)nickel(II) chloride (TTNC) has been described. The reduction in the intensity observed in powder X-ray diffraction of doped specimen and slight shifts in vibrational frequencies of doped specimens confirm the lattice stress as a result of doping. Surface morphological changes due to doping of the Sr(II) are observed by scanning electron microscopy. The incorporation of metal into the host crystal lattice was confirmed by energy dispersive X-ray spectroscopy. Lattice parameters are determined by single crystal XRD analysis. The thermogravimetric and differential thermal analysis studies reveal the purity of the materials and no decomposition is observed up to the melting point. The nonlinear optical properties of the doped and undoped specimens were studied. Theoretical calculations were performed using the Density functional theory (DFT) method with B3LYP/LANL2DZ as the basis set. The molecular geometry and vibrational frequencies of TTNC in the ground state were calculated and the observed structural parameters of TTNC are compared with parameters obtained from single crystal X-ray studies. The atomic charge distributions are obtained by Mulliken charge population analysis. The first-order molecular hyperpolarizability, polarizability and dipole moment were derived.


Assuntos
Complexos de Coordenação/química , Metais Alcalinoterrosos/química , Cristalização , Cristalografia por Raios X , Análise Diferencial Térmica , Microscopia Eletrônica de Varredura , Modelos Moleculares , Estrutura Molecular , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 805-13, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25150431

RESUMO

Single crystals of 4-aminopyridinium picrate (APP) were grown by slow evaporation of a mixed solvent system methanol-acetone (1:1, v/v) containing equimolar quantities of 4-aminopyridine and picric acid. Structure is elucidated by single crystal XRD analysis and the crystal belongs to monoclinic system with four molecules in the unit cell (space group P21/c) and the cell parameter values are, a=8.513 Å (±0.015), b=11.33 Å (±0.02), c=14.33 Å (±0.03) and ß=104.15° (±0.019), V=1340 A(3) (±6) with refined R factors R1=0.0053 and wR2=0.0126. The electron density mapping is interpreted to find coordinates for each atom in the crystallized molecules. The various functional groups present in the molecule are confirmed by FT-IR analysis. UV-visible spectral analysis was used to determine the band gap energy of 4-aminopyridinium picrate. Powder X-ray diffraction pattern reveals the crystallinity of the as-grown crystal and it closely resembles the simulated XRD from the single crystal XRD analysis. Scanning electron microscopy reveals the surface morphology of the grown crystal. Optimized geometry is derived by Hartree-Fock theory calculations and the first-order molecular hyperpolarizability (ß), theoretically calculated bond length, bond angles and excited state energy from theoretical UV-vis spectrum were estimated.


Assuntos
Modelos Moleculares , Picratos/química , Compostos de Piridínio/química , Simulação por Computador , Cristalização , Elétrons , Microscopia Eletrônica de Varredura , Pós , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Difração de Raios X
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 125: 308-12, 2014 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-24562162

RESUMO

Single crystals of alkali metal caesium(I) doped bis(thiourea)zinc(II) chloride are grown at room temperature by slow evaporation solution growth technique. Powder XRD studies reveal some interesting features in the XRD profiles with changes in intensity patterns in doped specimen due to stress development in the crystal. The incorporation of Cs(I) into the crystal lattice was confirmed by energy dispersive X-ray spectroscopy. Slight shifts in vibrational patterns of doped specimen indicate that the crystal undergoes considerable lattice stress as result of doping. SEM studies of pure and doped samples reveal the external morphology. Thermogravimetric and differential thermal studies reveal the purity of the material and the specimens are stable up to the melting point. The optical studies reveal that absorption is minimum in the visible region and doping influenced the diffuse reflectance spectrum. The band gap energies of the pure and doped specimens were estimated by the application of Kubelka-Munk algorithm.


Assuntos
Césio/química , Fenômenos Ópticos , Compostos Organometálicos/química , Temperatura , Cristalização , Análise Diferencial Térmica , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Vibração , Difração de Raios X
9.
Artigo em Inglês | MEDLINE | ID: mdl-24513714

RESUMO

Transparent optical quality single crystals of imidazolium L-tartrate (IMLT) were grown by conventional slow evaporation solution growth technique. Crystal structure of the as-grown IMLT was determined by single crystal X-ray diffraction analysis. Thermal analysis reveals the purity of the crystal and the sample is stable up to the melting point. Good transmittance in the visible region is observed and the band gap energy is estimated using diffuse reflectance data by the application of Kubelka-Munk algorithm. The powder X-ray diffraction study reveals the crystallinity of the as-grown crystal and it is compared with that of the experimental one. An additional peak in high resolution X-ray diffraction (HRXRD) indicates the presence of an internal structural low angle boundary. Second harmonic generation (SHG) activity of IMLT is significant as estimated by Kurtz and Perry powder technique. HOMO-LUMO energies and first-order molecular hyperpolarizability of IMLT have been evaluated using density functional theory (DFT) employing B3LYP functional and 6-31G(d,p) basis set. The optimized geometry closely resembles the ORTEP. The vibrational patterns present in the molecule are confirmed by FT-IR coinciding with theoretical patterns.


Assuntos
Imidazóis/química , Modelos Moleculares , Tartaratos/química , Temperatura , Cristalização , Análise Diferencial Térmica , Elétrons , Conformação Molecular , Pós , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
10.
Artigo em Inglês | MEDLINE | ID: mdl-24508881

RESUMO

Single crystals of 4-benzoylpyridine isonicotinyl hydrazone monohydrate were grown by slow evaporation solution growth technique from ethanol at room temperature. It belongs to triclinic system with space group P1¯ and the cell parameters are, a=8.9250(2) Å, b=9.1540(2) Å, c=10.87500(10) Å and V=797.88(3) Å(3). Powder XRD closely resembles with that of simulated pattern from single crystal XRD. The characteristic functional groups present in the molecule are confirmed by FT-IR and FT-Raman analyses. The crystal is transparent in the visible region having a lower optical cut-off at ∼420 nm and the band gap energies are estimated by the application of Kubelka-Munk algorithm. Thermal analysis by TG/DTA indicates the stability of the material. The scanning electron microscopy studies reveal the surface morphology of the as-grown crystal. Mass spectrometry provides information pertaining to the structure and molecular weight of the compound. Theoretical calculations were performed using Hartree-Fock method with 6-31G(d,p) as the basis set for to derive the optimized geometry, dipole moment and first-order molecular hyperpolarizality (ß) values.


Assuntos
Hidrazonas/química , Hidrazonas/síntese química , Ácidos Isonicotínicos/química , Ácidos Isonicotínicos/síntese química , Temperatura , Cristalização , Análise Diferencial Térmica , Espectrometria de Massas , Microscopia Eletrônica de Varredura , Conformação Molecular , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termogravimetria , Vibração , Difração de Raios X
11.
Artigo em Inglês | MEDLINE | ID: mdl-24177872

RESUMO

Single crystals of (2E,6E)-2-benzylidine-6-(4-methoxybenzylidine)cyclohexanone are grown by slow evaporation of ethanolic solution at room temperature. The characteristic functional groups present in the molecule are confirmed by Fourier transform infrared and Fourier transform Raman analyses. The scanning electron microscopy study reveals the surface morphology of the material. Thermogravimetric/differential thermal analysis study reveals the purity of the material and the crystal is transparent in the visible region having a lower optical cut-off at ∼487nm. The second harmonic generation efficiency of as-grown material is estimated by Kurtz and Perry technique. Optimized geometry has been derived using Hartree-Fock calculations performed at the level 6-31G (d,p) and the first-order molecular hyperpolarizability (ß) is estimated. The specimen is further characterized by nuclear magnetic resonance spectroscopy.


Assuntos
Compostos de Benzilideno/química , Cicloexanonas/química , Compostos de Benzilideno/síntese química , Cristalização , Cicloexanonas/síntese química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
12.
Artigo em Inglês | MEDLINE | ID: mdl-22925910

RESUMO

The influence of strontium doping on the properties of bis(thiourea)zinc(II) chloride (BTZC) crystals has been described. The reduction in the intensity observed in powder X-ray diffraction of doped specimen and slight shifts in vibrational frequencies confirm the lattice stress as a result of doping. The incorporation of Sr(II) into the crystal lattice was confirmed by energy dispersive X-ray spectroscopy (EDS). Surface morphological changes due to doping of the alkaline earth metal are observed by scanning electron microscopy (SEM). The crystal is transparent in the entire visible region having a lower optical cut-off at ~308 nm with a band gap energy of 4.06 eV. The DSC studies reveal the purity of the materials and no decomposition is observed up to the melting point. Dielectric studies show that the isovalent ion Sr(II)-doping altered the dielectric properties of the host crystal.


Assuntos
Eletricidade , Fenômenos Ópticos , Compostos Organometálicos/química , Estrôncio/química , Temperatura , Absorção , Varredura Diferencial de Calorimetria , Cristalização , Microscopia Eletrônica de Varredura , Pós , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
13.
Artigo em Inglês | MEDLINE | ID: mdl-22446769

RESUMO

Single crystals of benzophenone oxime (BPO) have been grown by slow evaporation solution growth technique from ethanol at room temperature. The single crystal X-ray diffraction study reveals that the crystal belongs to monoclinic system and cell parameters are, a=9.459 Å, b=8.383 Å, c=26.690 Å, v=2115 Å(3) and ß=92.807°. The structure and the crystallinity of the materials were further confirmed by powder X-ray diffraction analysis. The various functional groups present in the molecule are confirmed by FT-IR analysis. The TG/DSC studies reveal the purity of the material and the crystals are transparent in the entire visible region having a lower optical cut-off at ~300 nm. The crystalline perfection was evaluated by high-resolution X-ray diffraction (HRXRD). The crystal is further characterized by Kurtz powder technique, dielectric studies and microhardness analysis.


Assuntos
Benzofenonas/química , Oximas/química , Cristalização , Cristalografia por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Indian J Surg ; 69(5): 187-90, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23132979

RESUMO

CONTEXT: The art of administering immunosuppression lies in the ability to achieve a delicate balance between rejection and infection, thus maximizing patient survival and minimizing morbidity. AIMS: To analyze the effect of immunosuppression strategies following liver transplant on the incidence of acute rejection, bile leak, renal dysfunction and posttransplant graft unrelated infection. SETTINGS AND DESIGN: A retrospective analysis of immunosuppression regimens in 57 liver transplant recipients between Jan 1998 to July 2004 at a single institution. METHODS AND MATERIAL: For the purpose of study, the patients were divided into two groups: A - Cyclosporine based therapy (n=37), and B - Tacrolimus based therapy (n=20). In addition, both groups received Azathioprine or Mycophenolate mofetil with steroids. There were two subgroups in each Group A and B: Group C - Received induction using IL2Rab (n=5), and D - Where Sirolimus was used instead of Mycophenolate mofetil (N=7). The subgroups were equally distributed among the basic groups. The regimen was started based on one of the standard protocols but changes were made according to the clinical status of each patient. STATISTICAL ANALYSIS USED: The statistical analysis was done using Chi square test on SPSS12. RESULTS: A lower incidence of rejection was observed in Tacrolimus group compared to Cyclosporine group. There was an unacceptably high incidence of bile leak in patients where Sirolimus was used as an adjunct. IL2Rab enabled us to maintain a lower trough level of Tacrolimus for maintenance and enabled us to discontinue steroids earlier. CONCLUSIONS: Based on this study we dropped Sirolimus from our immunosuppression protocol and the encouraging results obtained with tacrolimus based therapy have supported its use as standard therapy in our immunosuppression regimens.

15.
Echocardiography ; 22(1): 9-13, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15660681

RESUMO

OBJECTIVE: Large uncomplicated atrial septal defect (ASD) alters the pulmonary venous flow (PVF) pattern. We aimed to study the role of transthoracic echocardiography (TTE) in estimating the PVF Doppler abnormalities in ASD. By repeating the study soon after ASD closure, we correlated the hemodynamics of atrial shunting with PVF patterns. METHODS: This study was performed in a tertiary care referral teaching hospital in 2003. The TTE PVF patterns of 34 patients with ASD were studied. TTE study was reported by two blinded investigators independently. Surgical closure of ASD was done on eleven patients and the early postoperative PVF Doppler pattern was also studied with TTE. RESULTS: PVF patterns were adequately recorded in 34 of 38 (90%) subjects with ASD with equal male: female ratio (n = 17 each). The mean age of the study group was 21.4 +/- 8.7 years. ASD ranged from 10 to 38 mm in diameter with a mean of 18 +/- 4.2 mm. Continuous antegrade wave (CAW, mean 68.45 +/- 13.6 cm/s) replaced normally occurring S and D waves in all ASD patients. The atrial reversal wave was reduced or absent (mean 20.18 +/- 3.28 cm/sec). After ASD closure, the CAW was replaced by the S (46.18 +/- 7.5 cm/sec) and D waves (57.72 +/- 9.7 cm/sec) with increase in atrial reversal wave to 27.81 +/- 5.1 cm/sec. CONCLUSIONS: The S and D antegrade waves normally seen in PVF are replaced by a continuous antegrade wave in ASD. Atrial reversal wave is also reduced. PVF waveform becomes normal after ASD closure. TTE PVF Doppler pattern can help estimate ASD hemodynamics.


Assuntos
Ecocardiografia Doppler em Cores/métodos , Comunicação Interatrial/diagnóstico por imagem , Circulação Pulmonar/fisiologia , Veias Pulmonares/diagnóstico por imagem , Adolescente , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Comunicação Interatrial/fisiopatologia , Humanos , Masculino , Contração Miocárdica/fisiologia , Estudos Retrospectivos
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