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1.
Phys Chem Chem Phys ; 17(45): 30450-60, 2015 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-26510134

RESUMO

Zinc oxide (ZnO) nanostructures with different morphologies are prepared in the presence of surface active molecules such as sodium dodecyl sulphate (SDS), Tween 80 and Triton X-100 by a chemical method. The experimental and first principles methods are employed to understand the microscopic origin of the asymmetric growth mechanism of ZnO in the presence of various surface active molecules. Effect of increase in the amount of surface active molecules and temperature is studied on the growth morphology of ZnO. An innovative method is developed to synthesize ZnO nanowires (NWs) in the presence of SDS. Spherical nanoparticles (NPs) to spherical clusters are obtained in the presence of Triton X-100 and Tween 80. These results are then supported by first principles calculations. The adsorption of the -OH functional group on both polar and nonpolar surfaces of ZnO is modelled by using density functional theory (DFT). The calculated binding energy (BE) is almost equivalent on both the surfaces with no preference on any particular surface. The calculated value of BE shows that the -OH group is physio-adsorbed on both the surfaces. This results in the spherical morphology of nanoparticles prepared in the presence of Tween 80. Bader charge analysis shows that the charge transfer mainly takes place on top two layers of the ZnO(101[combining macron]0) surface. The absence of high values of electron localization function (ELF) reflects the lack of covalent bonding between the -OH group and the ZnO(101[combining macron]0) surface.

2.
Saudi J Biol Sci ; 30(1): 103493, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36466218

RESUMO

To increase the insecticidal potency of the entomopathogen, Metarhizium anisopliae (Metsch.) Sorok, the fungus was genetically modified with scorpion neuro ß-toxin LqqIT1a and two different insect specific heterologous toxic proteins viz., Cry1a and GNA. LqqIT1 is an anti-insect neurotoxin derived from yellow scorpion, Leiurus quinquestriatus quinquestriatus (Ehren.). The present study reports the bio-efficacy of genetically modified fungus, M. anisopliae, in which scorpion neurotoxin gene 'LqqIT1' is stacked in its genome, for improved efficacy against the tobacco caterpillar, Spodoptera litura (Fab.) and Aphis craccivora (Koch). All the transformed clones of M. anisopliae were found potent against S. litura and A. craccivora under laboratory conditions. The virulent clones viz., Ma-2(2), Ma-2(7) and MaGKS-14 caused 40 to 90 per cent mortality at fourth day of treatment. Compared to untransformed parent strain, Ma-C, the median lethal time of transformed clones Ma-2(2), Ma-2(7) and MaGKS-14 got reduced by 2, 3 and 3-folds, respectively. No significant differences were noted with respect to percent mortality of transformed clone, MaGKS-13 in comparison to untransformed strain Ma-C. The results indicated that the incorporation of LqqIT1 toxin gene enhanced the potency of strain Ma-C, against immature stages of S. litura and A. craccivora by shortening the median lethal time without affecting conidial development. Therefore, LqqIT1 scorpion toxin gene showed the potential to improve efficacy of M. anisopliae against lepidopteran and hemipteran insects.

3.
Phys Rev Lett ; 106(21): 214503, 2011 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-21699304

RESUMO

Direct real-time visualization and measurement of laser-driven shock generation, propagation, and 2D focusing in a sample are demonstrated. A substantial increase of the pressure at the convergence of the cylindrical acoustic shock front is observed experimentally and simulated numerically. Single-shot acquisitions using a streak camera reveal that at the convergence of the shock wave in water the supersonic speed reaches Mach 6, corresponding to the multiple gigapascal pressure range ∼30 GPa.

4.
J Phys Condens Matter ; 21(22): 225006, 2009 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21715770

RESUMO

Thin films of zinc phthalocyanine have been deposited on KBr and glass substrates by the thermal evaporation method and characterized by the x-ray diffraction, optical, infrared and Raman techniques. The observed x-ray diffraction and infrared absorption spectra of as-deposited thin films suggest the presence of an α crystalline phase. Infrared and Raman spectra of thin films after exposure to vapours of ammonia and methanol have also been recorded. Shifts in the position of some IR and Raman bands in the spectra of exposed films have been observed. Some bands also show changes in their intensity on exposure. Increased charge on the phthalocyanine ring and out-of-plane distortion of the core due to interaction between zinc phthalocyanine and vapour molecules involving the fifth coordination site of the central metal ion may be responsible for the band shifts. Changes in the intensity of bands are interpreted in terms of the lowering of molecular symmetry from D(4h) to C(4v) due to doming of the core. Molecular parameters and Mulliken atomic charges of zinc phthalocyanine and its complexes with methanol and ammonia have been calculated from density functional theory. The binding energy of the complexes have also been calculated. Calculated values of the energy for different complexes suggest that axially coordinated vapour molecules form the most stable complex. Calculated Mulliken atomic charges show net charge transfer from vapour molecules to the phthalocyanine ring for the most stable complex.

5.
Int J Clin Pharmacol Ther ; 46(10): 511-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18826865

RESUMO

OBJECTIVE: The objective was to study the effect of grape juice and orange juice on the pharmacokinetics (PK) and pharmacodynamics (PD) of diltiazem in healthy human volunteers. METHODOLOGY: The study design was open-label, balanced, randomized, 3-period, single-dose and crossover. A group of 12 healthy, adult, male human volunteers received a single oral dose of diltiazem 180 mg extended release capsule on three different occasions: with 200 ml of water, with 200 ml of grape juice and with 200 ml of orange juice in random order. A washout period of 7 days was kept between each study period. Serial blood samples were collected up to 24 h post dose and assayed for diltiazem using a specific and validated HPLC method. Blood pressure (BP) and ECG measurements were done at 0, 1, 2, 3, 4, 6, 8, 10, 12, 16 and 24 h post dose. Analysis of variance was carried out using logarithmic transformations of AUC and Cmax as well as nontransformed tmax. RESULTS: No significant change was observed in heart rate and BP. The median tmax was identical in all three occasions. The 90% CI of the Cmax ratios for orange juice/water were 104.59 - 114.86 and for grape juice/water were 93.91 - 103.13. Similarly, the 90% CI of the AUC0-inf ratios for orange juice and grape juice vs. water were 103.68 - 119.83 and 88.56 - 104.06, respectively. Since these values fall within the bioequivalence criteria of 80 - 120% limits, our study demonstrates absence of interaction of diltiazem with grape juice or orange juice. CONCLUSIONS: There is no significant influence of grape juice or orange juice on the pharmacokinetics and pharmacodynamics of diltiazem.


Assuntos
Bebidas , Bloqueadores dos Canais de Cálcio/farmacocinética , Citrus sinensis , Diltiazem/farmacocinética , Vitis , Adulto , Área Sob a Curva , Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/farmacologia , Cápsulas , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Preparações de Ação Retardada , Diltiazem/administração & dosagem , Diltiazem/farmacologia , Esquema de Medicação , Interações Alimento-Droga , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino
6.
Bioresour Technol ; 99(9): 3896-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17869506

RESUMO

The studies were carried out for the isolation of efficient pullulan producing strains of Aureobasidium pullulans. Five strains were isolated from phylloplane of different plants. Amongst these, three were producing black pigment melanin, while the remaining two produced pink pigment. These two color variant isolates of A. pullulans were designated as FB-1 and FG-1, and obtained from phylloplane of Ficus benjamina and Ficus glometa, respectively. The parameters employed for the identification of the isolates included morphology, nutritional assimilation patterns and exopolysaccharide (EPS) production. Isolates were compared with standard cultures for EPS production. A. pullulans FB-1 was the best producer of pullulan giving up to 1.9, 1.4 and 1.7 times more pullulan than the control of A. pullulans NCIM 976, NCIM 1048 and NCIM 1049, respectively. The IR spectra of the isolates and standard strains revealed that the polysaccharide was pullulan, but not aubasidan. The study also supported the fact that A. pullulans is a ubiquitous organism and phylloplane being the important niche of the organism.


Assuntos
Ascomicetos/isolamento & purificação , Cor , Ficus/microbiologia , Glucanos/biossíntese , Polissacarídeos/biossíntese , Polissacarídeos/química , Espectrofotometria Infravermelho
7.
Artigo em Inglês | MEDLINE | ID: mdl-17572136

RESUMO

Infrared absorption spectra of copper phthalocyanine in KBr pellet and pyridine solution in 400-1625 and 2900-3200 cm(-1)regions are reported. In the IR spectra of solid sample, presence of weak bands, which are forbidden according to the selection rules of D4h point group, is explained on the basis of distortion in the copper phthalocyanine molecule caused by the crystal packing effects. Observation of a new band at 1511 cm(-1) and change in intensity of some other bands in pyridine are interpreted on the basis of coordination of the solvent molecule with the central copper ion.


Assuntos
Indóis/química , Compostos Organometálicos/química , Piridinas/química , Espectrofotometria Infravermelho/métodos , Estrutura Molecular
8.
South Asian J Cancer ; 7(2): 87-90, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29721470

RESUMO

The use of radiation therapy after mastectomy (PMRT) has been limited to those patients who are at significant risk of cancer recurring in the chest wall or in the nodal basins. The use of PMRT has been widely accepted for patients with four or more positive lymph nodes,[1],[2] but there is still controversy regarding the value of PMRT for those with one to three positive nodes. This expert group used data from published literature, practical experience and opinion of a large group of academic oncologists to arrive at these practical consensus recommendations for the benefit of community oncologists.

9.
Artigo em Inglês | MEDLINE | ID: mdl-16458581

RESUMO

Resonance Raman spectra of free-base tetraphenylporphine and its dication obtained with 441.6, 476.5, 488.0 and 514.5 nm excitation lines in the frequency region 100-1625 cm(-1) are reported. Some bands due to in-plane and out-of-plane vibrational modes, which are symmetry forbidden under ideal D(2h), are also seen in the Raman spectra of these molecules. These bands arise due to dynamic and/or static coupling of out-of-plane modes with the allowed in-plane modes. Dynamic coupling may be facilitated by the proton tunneling, while static coupling is due to out-of-plane distortion in the geometrical structure of the molecule. Shift in the positions for certain bands in the Raman spectra of dication are interpreted on the basis of electronic changes due to sharing of electrons of the B(1u) orbital by the two added protons.


Assuntos
Porfirinas/química , Análise Espectral Raman/métodos , Modelos Químicos , Modelos Moleculares , Nitrogênio/química , Prótons , Espectrofotometria , Espectrofotometria Infravermelho/métodos , Raios Ultravioleta , Vibração
10.
Artigo em Inglês | MEDLINE | ID: mdl-26580511

RESUMO

Structure, vibrational and nuclear magnetic resonance spectra, and antioxidant action of ascorbic acid towards hydroxyl radicals have been studied computationally and in vitro by ultraviolet-visible, nuclear magnetic resonance and vibrational spectroscopic techniques. Time dependant density functional theory calculations have been employed to specify various electronic transitions in ultraviolet-visible spectra. Observed chemical shifts and vibrational bands in nuclear magnetic resonance and vibrational spectra, respectively have been assigned with the help of calculations. Changes in the structure of ascorbic acid in aqueous phase have been examined computationally and experimentally by recording Raman spectra in aqueous medium. Theoretical calculations of the interaction between ascorbic acid molecule and hydroxyl radical predicted the formation of dehydroascorbic acid as first product, which has been confirmed by comparing its simulated spectra with the corresponding spectra of ascorbic acid in presence of hydrogen peroxide.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 61(13-14): 3070-6, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16165054

RESUMO

We present here the infrared absorption spectra of free-base tetraphenylporphine and its dication. Most of the allowed IR bands of porphyrin skeletal are observed in pairs due to two-fold symmetry of the free-base tetraphenylporphine. Observation of some new bands, disappearance of few bands in the IR spectrum of dication are interpreted on the basis of point group symmetry S4. Intensity change in the observed bands due to vibrational motion of the phenyl rings for dication is also explained on the basis of symmetry of dication. Sharing of electrons of the B(1u) orbitals by the two added protons are responsible for the shifts in the position of certain IR bands for dication.


Assuntos
Porfirinas/química , Modelos Químicos , Estrutura Molecular , Espectrofotometria Infravermelho , Vibração
12.
Artigo em Inglês | MEDLINE | ID: mdl-15649797

RESUMO

We report here electronic absorption, fluorescence and resonance Raman studies of rhodamine 6G laser dye dispersed in the polymethylcyanoacrylate matrix. In the electronic absorption and fluorescence spectra of dispersed rhodamine 6G, band maxima are red shifted compared to solution. Raman spectra show some new bands. These spectral changes arise due to matrix effect and interaction between rhodamine 6G and the host material involving amine group of rhodamine.


Assuntos
Físico-Química/métodos , Cianoacrilatos/química , Corantes Fluorescentes/química , Rodaminas/química , Espectrometria de Fluorescência/métodos , Espectrofotometria/métodos , Análise Espectral Raman/métodos , Corantes/farmacologia , Elétrons , Etilaminas/química , Polímeros/química , Rodaminas/análise
13.
Artigo em Inglês | MEDLINE | ID: mdl-26309424

RESUMO

AIM: To study the pattern of various adverse drug reactions (ADRs) occurring in children attending the Department of Pediatrics, SMGS Hospital, Jammu over 1 year. SUBJECTS AND METHODS: This was a prospective study, with study population of patients attending Department of Pediatrics over a period of 1 year. A structured format was used to enroll the participants. A pilot study was conducted to test the suitability of the format and feasibility of the study. The study was carried out to review various pattern of ADRs by using the Naranjo probability scale, and severity was assessed by using the Hartwig severity scale. ADRs were classified according to the classification used by the Adverse Drug Reaction Monitoring Center, Central Drugs Standard Control Organization, New Delhi, India. RESULTS: In the present study, 104 patients were found to have developed acute drug reactions. Among these, 83.6% were type B, 14.42% type A, and 1.92% were type U. Furthermore, 25.96% ADRs were due to anticonvulsants, followed by antibiotics (22.11%), antipyretics (11.53%), vaccination (8.65%), steroids (6.73%), decongestants (5.67%), snake antivenom and antiemetics (3.84%), and fluids, insulin, and antacids (1.92%). The patients' dermatological system was involved in 67.30%, followed by the central nervous system (CNS) in 11.53% patients. Renal system was involved in 6.73% patients. Cardiac, musculoskeletal, metabolic, and other systems were involved in 4.80%, 3.84%, 2.88%, and 0.96%, respectively. According to the Hartwig severity scale of ADRs, 64.4% patients had moderate ADRs, 29.8% patients had severe ADRs, and 5.76% had mild ADRs. In the present study, 64.4% patients expressed moderate severity, whereas 29.8% expressed high severity and 5.76% expressed mild ADRs. CONCLUSION: ADRs were seen in 71% of the patients between 1 and 5 years of age, 26% in the age group of 5-10 years, and 3% were more than 10 years old. Anticonvulsants (25.96%) and antibiotics (22.11%) were responsible for majority of ADRs. Rash (55.76%) was the most common presentation of ADR. Owing to the high number of ADRs, the present study points to the need for rigid adverse drug monitoring among pediatric patients to ensure the safety of drug therapy.

14.
Artigo em Inglês | MEDLINE | ID: mdl-25978018

RESUMO

The vibrational properties of glutathione have been investigated by infrared absorption and Raman spectroscopic techniques, and density functional theory calculations at the B3LYP/6-31+G(d,p) level. Assignments of all the experimentally observed vibrational bands have been done with the help of simulated vibrational spectra and potential energy distribution calculations of glutathione water cluster, which includes the effect of hydrogen bonding. Optimized molecular parameters of energy minimized structure have been compared with the available experimental values. Calculated molecular parameters of glutathione-water cluster match well with the experimental values. Some of the calculated molecular parameters and vibrational frequencies of vapor phase glutathione-water cluster suggest participation of some atoms of glutathione in hydrogen bonding. Experimentally observed UV-Visible absorption spectrum of glutathione has also been reported. Observed band at 203 nm has been assigned to electronic transitions calculated with time dependent density functional theory.


Assuntos
Glutationa/química , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Vibração , Elétrons , Conformação Molecular , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Science ; 186(4165): 689, 1974 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-17792250
16.
Talanta ; 35(9): 685-91, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18964595

RESUMO

The dibenzyldithiocarbamate chelates of Cd(II), Pb(II), Bi(III), Hg(II), Ni(II), Cu(II), As(III), Fe(III), Co(III) and In(III) are separated by reversed-phase HPLC in isocratic conditions. The procedure is simple, rapid, and gives satisfactory separations with high efficiency and sensitivity at mobile phase compositions very rich in organic modifier (85-88% CH(3)CN). The detection limits range from 1.4 to 14 mug/1. The elution order is correlated with the ability of the central metal atom to affect the electronic distribution of the ligand, which has readily polarizable donor atoms. Infrared spectroscopy data corroborate this assumption.

17.
J Assoc Physicians India ; 50: 606-7, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12164425

RESUMO

We report a case of scorpion sting who presented with right hemiparesis and deranged level of consciousness. Prolonged BT/CT, decreased platelet counts, prolongation of PT and APTT with positive fibrinogen degradation products (FDP) D-dimer and CT scan findings of multiple cerebral haemorrhagic infarct indicating the presence of disseminated intravascular coagulation (DIC) as a cause of hemiparesis. Patient was managed with fresh blood transfusion and conventional treatment with favourable outcome.


Assuntos
Paresia/etiologia , Picadas de Escorpião/complicações , Adulto , Animais , Infarto Cerebral/etiologia , Coagulação Intravascular Disseminada/etiologia , Humanos , Masculino , Picadas de Escorpião/diagnóstico , Picadas de Escorpião/terapia , Escorpiões
18.
J Telemed Telecare ; 10(3): 180-2, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15165446

RESUMO

Ultrasound examinations were carried out by a general practitioner on patients who presented with lower urinary tract symptoms. To assist in the interpretation of ultrasound anatomy, still images were captured during the ultrasound examination and transmitted to a university expert. In total 15 telemedicine sessions were conducted, using PC-based videoconferencing equipment connected by ISDN at 128 kbit/s. Fifteen patients were randomly selected and both the transmitted and hard-copy images (printed on thermal paper) were graded for technical quality. Data were missing for 13 of the possible 105 paired comparisons, as some images could not be evaluated. Overall agreement between the technical quality scores for the transmitted and hard-copy images was poor (weighted kappa=0.04). The 105 transmitted images were also rated for their diagnostic quality: 90% were classified as diagnostic and 10% were judged to be non-diagnostic. The results show the feasibility of tele-ultrasound in primary care. The general practitioner concerned benefited from regular ultrasound training and supervision, and achieved a satisfactory level of clinical competency in scanning the prostate, bladder and kidneys.


Assuntos
Instrução por Computador/métodos , Educação Médica Continuada/métodos , Medicina de Família e Comunidade/educação , Doenças Prostáticas/diagnóstico por imagem , Telemedicina/métodos , Competência Clínica , Inglaterra , Estudos de Viabilidade , Humanos , Masculino , Ultrassonografia
19.
Health Serv J ; 107(5576): 26-7, 1997 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-10174934

RESUMO

Most initiatives to cope with increased winter workloads come from hospitals. The potential for co-operative efforts between hospitals and general practice is largely unexplored. One general practice, a total purchasing pilot site, plans to minimise the demand for emergency admissions by identifying patients at risk and having a nurse visit them in autumn to check their health. The practice estimates the project will be self-financing if it saves 12 admissions.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Medicina de Família e Comunidade/organização & administração , Hospitais Públicos/organização & administração , Relações Interinstitucionais , Admissão do Paciente/estatística & dados numéricos , Agendamento de Consultas , Hospitais Públicos/estatística & dados numéricos , Visita Domiciliar/estatística & dados numéricos , Admissão e Escalonamento de Pessoal , Estações do Ano , Medicina Estatal , Reino Unido
20.
Artigo em Inglês | MEDLINE | ID: mdl-24041531

RESUMO

We report the infrared absorption and Raman spectra of melatonin recorded with 488 and 632.8 nm excitations in 3600-2700 and 1700-70 cm(-1) regions. Further, we optimized molecular structure of the three conformers of melatonin within density functional theory calculations. Vibrational frequencies of all three conformers have also been calculated. Observed vibrational bands have been assigned to different vibrational motions of the molecules on the basis of potential energy distribution calculations and calculated vibrational frequencies. Observed band positions match well with the calculated values after scaling except NH stretching mode frequencies. It is found that the observed and calculated frequencies mismatch of NH stretching is due to intermolecular interactions between melatonin molecules.


Assuntos
Elétrons , Melatonina/química , Análise Espectral Raman , Vibração , Conformação Molecular , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
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