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1.
Nanotechnology ; 35(31)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38670075

RESUMO

Theoretical examination based on first principle computation has been conducted for van der Waals heterostructure (vdwHS) GaAlS2/HfS2including structural, optoelectronic and photocatalytic characteristics. From the adhesion energy calculation, the AB configuration of GaAlS2/HfS2vdwHS is the most stable. A type-II GaAlS2/HfS2vdwHS is a dynamically and thermally stable structure. The band edge position, projected band, and projected charge densities verify the type-II alignment of GaAlS2/HfS2vdwHS. For GaAlS2/HfS2, GaAlS2is acting as a donor and HfS2is acting as an acceptor ensured by the charge density difference plot. The electron localized function validates the weak van der Waals interaction between GaAlS2and HfS2. The GaAlS2/HfS2vdwHS possess an indirect bandgap of 1.54 eV with notable absorption in the visible range. The findings assure that the GaAlS2/HfS2vdwHS is an efficient photocatalyst for pH 4-8. The band alignment of GaAlS2/HfS2is suitable for Z-scheme charge transfer. The strain influenced band edge suggests that the GaAlS2/HfS2vdwHS remains photocatalytic for strain-4%to+6%in both cases of uniaxial and biaxial strains.

2.
Nanotechnology ; 35(11)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38081073

RESUMO

The computational study of the van der Waals hetero (vdW) bilayer GeI2/InTe has been carried out in present study. The isolated monolayer GeI2and InTe have been studied first and the results were compared to the previous studies. The possible stackings are considered after the vdW interaction correction is applied in the structure relaxation. The vdW hetero bilayer stability has been checked from the phonon dispersion andab initioMolecular Dynamics calculations. The charge transfer from InTe to GeI2monolayer. Type-II indirect band gap (1.98, 2.01 eV) is verified by the projected band structure and band alignment calculations. The vdW hetero bilayer is a superior photocatalyst for the pH value up to pH = 0 to 11. The optical properties are calculated from the complex dielectric constant. The absorption coefficient shows the enhance absorption of light in the visible and ultraviolet regions. The vdW hetero bilayer has shown low reflectivity (37%) and a high refractive index (2.80) in the visible region. The enhanced optical properties have shown its possible applications in optoelectronic devices.

3.
Phys Chem Chem Phys ; 25(33): 22258-22274, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37577832

RESUMO

In this investigation, the structural, electronic, and optical properties of two-dimensional van der Waals heterostructure (vdwHS) PtSe2/GaSe with three different configurations have been studied using density functional theory with the generalized gradient approximation. All three optimized vdwHSs PtSe2/GaSe have positive phonon frequencies and hexagonal unit cells. The hybrid exchange-correlation functional has been employed to study the electronic properties of vdwHSs PtSe2/GaSe. The vdwHSs PtSe2/GaSe shows semiconducting behavior with indirect Type-II bandgaps, which have been confirmed by the charge density difference, electrostatic potential, work function, and band edge calculations. Additionally, from the band edge positions, the vdwHSs PtSe2/GaSe are analyzed for photocatalytic activities. The optical properties such as extinction coefficient, refractive index, reflectivity, energy loss spectrum, and absorption coefficient have been studied using norm-conserving pseudo-potentials. The vdwHSs PtSe2/GaSe exhibit consistent absorption from the visible to the ultraviolet region of the electromagnetic spectrum. From the obtained results, we conclude that vdwHSs PtSe2/GaSe could be utilized for H2 production through photocatalytic activity as well as for optoelectronic devices and their application.

4.
J Phys Condens Matter ; 35(47)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37536323

RESUMO

First principle calculations of novel two-dimensional (2D) group-III ternary chalcogenide monolayer (G3TCM) compounds have been carried out using density functional theory. The 2D hexagonal structure has a honeycomb-like appearance from both the top and bottom views. Both pristine and G3TCM compounds are energetically favourable and have been found to be dynamically stable via phonon calculations. Theab-initiomolecular dynamics calculations show the thermodynamical stability of the G3TCM compounds. The G3TCM compounds exhibit semiconductor behaviour with a decreased indirect bandgap compared to the pristine monolayers. Chalcogen atoms contribute mainly to the valence bands, while group-III atoms have a major contribution to the conduction band. A red shift has been observed in the absorption of light, mainly in the visible and ultraviolet regions, and the refractive index is increased compared to the pristine material. Both pristine and G3TCM compounds have been found to be more active in the ultraviolet region, and low reflection has been observed. In the 6-8 eV range of the ultraviolet region, zero reflection and the highest absorption are observed. The monolayer has shown potential applications in optoelectronics devices as an ultraviolet and visible light detector, absorber, coating material, and more. The band alignment of the 2D G3TCM monolayer is calculated to observe its photo-catalyst behaviour.

5.
Br J Oral Maxillofac Surg ; 59(8): 894-897, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34364712

RESUMO

Treatments facilitated by healthcare trusts are transformed into codes through which payments are organised. Accurate coding is essential for correct payment, inaccurate clinical coding results in significant loss of income. Our OMFS unit performs regular day-case procedures with data recorded in a standardised proforma. An audit was performed to determine the accuracy of ICD and OPCS codes generated by the OMFS department to identify factors contributing to inaccuracies leading to loss of income. All local anaesthetic and IV sedation cases were reviewed at two separate 3 monthly time frames within the OMFS department with 100 cases per cycle. A gold standard of 100% coding information recorded and accuracy were set. The first data cycle demonstrated a number of factors to improve the clinical coding process including implementing a new clinical coding form. This was utilised in the second audit cycle. Regarding ICD-10 the first audit cycle yielded a 65% accuracy of primary diagnoses. Following recommendations this improved to 72%. Coding accuracy in the first cycle was recorded as 62% with improvement to 78% in the second cycle. OPCS data accuracy was 80% in the first cycle improving to 90% in the second cycle. Secondary or bilateral procedures also showed improvement from 83% to 89% accuracy in the second cycle. Across the audit cycle £20,000 of revenue was generated. Inaccuracies in clinical coding reduces income, improved understanding of error sources can ensure income is commensurate with clinical activity.


Assuntos
Anestésicos Locais , Codificação Clínica , Anestesia Local , Procedimentos Cirúrgicos Eletivos , Humanos , Classificação Internacional de Doenças
6.
Shoulder Elbow ; 13(2): 223-232, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33897854

RESUMO

BACKGROUND: Limited evidence exists which details changes in quality of life, shoulder activity level, kinesiophobia, shoulder pain and disability following a first-time traumatic anterior shoulder dislocation (FTASD) in people treated non-operatively. This study had three objectives: (1) to examine quality of life, pain, disability and kinesiophobia after an FTASD within 12 weeks, (2) to examine whether these variables were different in people with and without recurrent shoulder instability and (3) to assess how these variables changed over 12 months. METHODS: A prospective cohort study was undertaken in people with an FTASD aged between 16 and 40 years. Measures of quality of life, kinesiophobia, shoulder activity, shoulder pain and disability were recorded within 12 weeks of an FTASD and at 3, 6, 9 and 12 months. RESULTS: An FTASD negatively impacted quality of life, shoulder pain and function and these variables improved over time. People with recurrent shoulder instability had poorer quality of life 12 months after an FTASD. Across the entire cohort, kinesiophobia did not significantly change across time in people following an FTASD. CONCLUSIONS: Quality of life was significantly affected by an FTASD in people with recurrent shoulder instability. Across the entire cohort of people with an FTASD, kinesiophobia remained elevated in people following an FTASD. LEVEL OF EVIDENCE: Level 1 prognostic study.

7.
Br Dent J ; 229(3): 148, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32811908
8.
J Laryngol Otol ; 134(4): 328-331, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32234081

RESUMO

OBJECTIVE: Convolutional neural networks are a subclass of deep learning or artificial intelligence that are predominantly used for image analysis and classification. This proof-of-concept study attempts to train a convolutional neural network algorithm that can reliably determine if the middle turbinate is pneumatised (concha bullosa) on coronal sinus computed tomography images. METHOD: Consecutive high-resolution computed tomography scans of the paranasal sinuses were retrospectively collected between January 2016 and December 2018 at a tertiary rhinology hospital in Australia. The classification layer of Inception-V3 was retrained in Python using a transfer learning method to interpret the computed tomography images. Segmentation analysis was also performed in an attempt to increase diagnostic accuracy. RESULTS: The trained convolutional neural network was found to have diagnostic accuracy of 81 per cent (95 per cent confidence interval: 73.0-89.0 per cent) with an area under the curve of 0.93. CONCLUSION: A trained convolutional neural network algorithm appears to successfully identify pneumatisation of the middle turbinate with high accuracy. Further studies can be pursued to test its ability in other clinically important anatomical variants in otolaryngology and rhinology.


Assuntos
Inteligência Artificial/normas , Doenças Nasais/etiologia , Seios Paranasais/diagnóstico por imagem , Tomografia Computadorizada por Raios X/instrumentação , Conchas Nasais/diagnóstico por imagem , Algoritmos , Austrália/epidemiologia , Feminino , Humanos , Masculino , Redes Neurais de Computação , Doenças Nasais/diagnóstico por imagem , Doenças Nasais/patologia , Doenças Nasais/cirurgia , Variações Dependentes do Observador , Estudos Retrospectivos , Conchas Nasais/patologia , Conchas Nasais/cirurgia
9.
Int Endod J ; 52(7): 935-948, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30758848

RESUMO

AIM: To evaluate the effect of collagen membrane on the healing of through-and-through periapical lesions using 2-dimensional (2D) and 3-dimensional (3D) imaging techniques. METHODOLOGY: Thirty-two patients with periapical radiolucencies measuring at least 10 mm and with confirmed loss of buccal and lingual cortical plates were randomly divided into GTR and control groups. Periapical surgery was performed in both groups, using a resorbable collagen membrane in the GTR group only. 2D healing was evaluated according to Molven's criteria, while 3D healing was assessed using modified PENN 3D criteria, RAC indices and the B index, 12 months after surgery. Data were analysed using Chi-square, Mann-Whitney and Wilcoxon signed rank tests. RESULTS: Thirty patients were analysed at the 12 months follow-up. Both groups had a significant reduction in the size of lesions [92 ± 12% (control) and 86 ± 14% (GTR) in 2D and 85 ± 19% (Control) and 82 ± 13% (GTR) in 3D], with no significant difference between the groups (P > 0.05). A total of 29(14 control, 15 GTR) teeth and 26(13 control, 13 GTR) teeth were classified as success according to Molven's (2D) and modified PENN 3D criteria, respectively, with no significant difference in success between 2D and 3D assessments. RAC indices of 3D images revealed the greatest percentage of complete healing in R scores (55% for Control, 41% for GTR), whereas cortical plate had the lowest percentage of healing (30% for Control, 27% for GTR) (P > 0.05). Only 2 (13%) patients in each group had complete healing using the B index. CONCLUSION: Periapical surgery with or without GTR was a predictable and viable solution for through-and-through lesions. There was no benefit in using a collagen membrane with regard to the outcome of periapical surgery in through-and-through lesions. Both cone beam computed tomography (CBCT) and periapical radiographs (PA) allowed similar assessment of healing after periapical surgery.


Assuntos
Colágeno , Cicatrização , Tomografia Computadorizada de Feixe Cônico , Regeneração Tecidual Guiada Periodontal , Humanos , Resultado do Tratamento
10.
Eur J Neurol ; 25(8): 1055-e82, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29611892

RESUMO

BACKGROUND AND PURPOSE: Treatments to facilitate recovery after traumatic brain injury (TBI) are urgently needed. We conducted a 9-month pilot, randomized placebo-controlled clinical trial to examine the safety and potential effects of the herbal supplement MLC901 (NeuroAiD II™) on cognitive functioning following TBI. METHODS: Adults aged 18-65 years at 1-12 months after mild or moderate TBI were randomized to receive MLC901 (0.8 g capsules 3 times daily) or placebo for 6 months. The primary outcome was cognitive functioning as assessed by the CNS Vital Signs online neuropsychological test. Secondary outcomes included the Cognitive Failures Questionnaire, the Rivermead Post-concussion Symptom Questionnaire (neurobehavioral sequelae), Quality of Life after Brain Injury, Hospital Anxiety and Depression Scale, Modified Fatigue Impact Scale and extended Glasgow Outcome Scale (physical disability). Assessments were completed at baseline and at 3-, 6- and 9-month follow-up. Linear mixed-effects models were conducted, with the primary outcome time-point of 6 months. RESULTS: A total of 78 participants [mean age 37.5 ± 14.8 years, 39 (50%) female] were included in the analysis. Baseline variables were similar between groups (treatment group, n = 36; control group, n = 42). Linear mixed-effects models controlling for time, group allocation, repeated measurements, adherence and baseline assessment scores revealed significant improvements in complex attention (P = 0.04, d = 0.6) and executive functioning (P = 0.04, d = 0.4) at 6 months in the MLC901 group compared with controls. There were no significant differences between the groups for neurobehavioral sequelae, mood, fatigue, physical disability or overall quality of life at 6 months. No serious adverse events were reported. CONCLUSIONS: MLC901 was safe and well tolerated post-TBI. This study provided Class I/II evidence that, for patients with mild to moderate TBI, 6 months of MLC901 improved cognitive functioning.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/psicologia , Cognição , Medicamentos de Ervas Chinesas/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Adolescente , Adulto , Idoso , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/prevenção & controle , Avaliação da Deficiência , Método Duplo-Cego , Função Executiva , Feminino , Escala de Resultado de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Projetos Piloto , Qualidade de Vida , Resultado do Tratamento , Adulto Jovem
11.
Br Dent J ; 222(10): 745, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28546601
12.
J Food Sci Technol ; 52(12): 7974-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26604369

RESUMO

Ultrafiltered milk (UF1 and UF2), ultrafiltrate retentate added milk (UF3 and UF4) and SMP added milk (UF0) were used for dahi preparation in the present study. Treatments were evaluated for rheological, textural and sensorial characteristics. Significant increase (p < 0.01) in values of firmness, stickiness, work of shear, work of adhesion and sensory scores, but significant decrease (p < 0.01) in whey syneresis values were observed with treatments UF1, UF2, UF3 and UF4 as compared to UF0. Principal component analysis (PCA) revealed that first four principal components (PC) explained 87.39 % relationship between samples and attributes. PC1 accounted for 48.34 % of data variance was characterized by protein content, firmness, work of shear, body & texture and opposed by total carbohydrates, stickiness, syneresis and work of adhesion. Total carbohydrates content (r = -0.982, P < 0.01), whey syneresis (r = -0.783, P < 0.01), stickiness (r = -0.729, P < 0.01) and work of adhesion (r = -0.684, P < 0.01) are negatively while body and texture (r = +0.600, P < 0.01), firmness (r = +0.574, P < 0.05) and work of shear (r = +0.538, P < 0.05) of dahi are highly positively correlated with protein content.

13.
Br J Sports Med ; 49(14): 913-22, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25900943

RESUMO

BACKGROUND: Recurrent instability following a first-time anterior traumatic shoulder dislocation may exceed 26%. We systematically reviewed risk factors which predispose this population to events of recurrence. METHODS: A systematic review of studies published before 1 July 2014. Risk factors which predispose recurrence following a first-time traumatic anterior shoulder dislocation were documented and rates of recurrence were compared. Pooled ORs were analysed using random-effects meta-analysis. RESULTS: Ten studies comprising 1324 participants met the criteria for inclusion. Recurrent instability following a first-time traumatic anterior shoulder dislocation was 39%. Increased risk of recurrent instability was reported in people aged 40 years and under (OR=13.46), in men (OR=3.18) and in people with hyperlaxity (OR=2.68). Decreased risk of recurrent instability was reported in people with a greater tuberosity fracture (OR=0.13). The rate of recurrent instability decreased as time from the initial dislocation increased. Other factors such as a bony Bankart lesion, nerve palsy and occupation influenced rates of recurrent instability. CONCLUSIONS: Sex, age at initial dislocation, time from initial dislocation, hyperlaxity and greater tuberosity fractures were key risk factors in at least two good quality cohort studies resulting in strong evidence as concluded in the GRADE criteria. Although bony Bankart lesions, Hill Sachs lesions, occupation, physiotherapy treatment and nerve palsy were risk factors for recurrent instability, the evidence was weak using the GRADE criteria-these findings relied on poorer quality studies or were inconsistent among studies.


Assuntos
Instabilidade Articular/etiologia , Luxação do Ombro/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Suscetibilidade a Doenças , Feminino , Humanos , Instabilidade Articular/patologia , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Fatores Sexuais , Luxação do Ombro/patologia , Adulto Jovem
14.
Infect Immun ; 81(12): 4635-48, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24101689

RESUMO

Global proteomic analysis was performed with Shigella flexneri strain 2457T in association with three distinct growth environments: S. flexneri growing in broth (in vitro), S. flexneri growing within epithelial cell cytoplasm (intracellular), and S. flexneri that were cultured with, but did not invade, Henle cells (extracellular). Compared to in vitro and extracellular bacteria, intracellular bacteria had increased levels of proteins required for invasion and cell-to-cell spread, including Ipa, Mxi, and Ics proteins. Changes in metabolic pathways in response to the intracellular environment also were evident. There was an increase in glycogen biosynthesis enzymes, altered expression of sugar transporters, and a reduced amount of the carbon storage regulator CsrA. Mixed acid fermentation enzymes were highly expressed intracellularly, while tricarboxylic acid (TCA) cycle oxidoreductive enzymes and most electron transport chain proteins, except CydAB, were markedly decreased. This suggested that fermentation and the CydAB system primarily sustain energy generation intracellularly. Elevated levels of PntAB, which is responsible for NADPH regeneration, suggested a shortage of reducing factors for ATP synthesis. These metabolic changes likely reflect changes in available carbon sources, oxygen levels, and iron availability. Intracellular bacteria showed strong evidence of iron starvation. Iron acquisition systems (Iut, Sit, FhuA, and Feo) and the iron starvation, stress-associated Fe-S cluster assembly (Suf) protein were markedly increased in abundance. Mutational analysis confirmed that the mixed-acid fermentation pathway was required for wild-type intracellular growth and spread of S. flexneri. Thus, iron stress and changes in carbon metabolism may be key factors in the S. flexneri transition from the extra- to the intracellular milieu.


Assuntos
Proteínas de Bactérias/metabolismo , Proteoma/metabolismo , Shigella flexneri/crescimento & desenvolvimento , Shigella flexneri/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/genética , Carbono/metabolismo , Linhagem Celular , Ciclo do Ácido Cítrico/fisiologia , Disenteria Bacilar/patologia , Fermentação/fisiologia , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Humanos , Ferro/metabolismo , Alça do Néfron/citologia , Alça do Néfron/microbiologia , Proteínas de Membrana Transportadoras/biossíntese , NADP Trans-Hidrogenases/biossíntese , Shigella flexneri/patogenicidade
15.
J Dev Orig Health Dis ; 4(2): 157-69, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25054682

RESUMO

Two pregnancy cohorts were used to investigate the association between single-nucleotide polymorphisms (SNPs) in genes within the insulin-like growth factor (IGF)-axis and antenatal and postnatal growth from birth to adolescence. Longitudinal analyses were conducted in the Raine pregnancy cohort (n = 1162) using repeated measures of fetal head circumference (HC), abdominal circumference (AC) and femur length (FL) from 18 to 38 weeks gestation and eight measures of postnatal height and weight (1-17 years). Replications of significant associations up to birth were undertaken in the Generation R Study (n = 2642). Of the SNPs within the IGF-axis genes, 40% (n = 58) were associated with measures of antenatal growth (P ⩽ 0.05). The majority of these SNPs were in receptors; IGF-1R (23%; n = 34) and IGF-2R (13%; n = 9). Fifteen SNPs were associated with antenatal growth (either AC or HC or FL) in Raine (P ⩽ 0.005): five of which remained significant after adjusting for multiple testing. Four of these replicated in Generation R. Associations were identified between 38% (n = 55) of the IGF-axis SNPs and postnatal height and weight; 21% in IGF-1R (n = 31) and 9% in IGF-2R (n = 13). Twenty-six SNPs were significantly associated with both antenatal and postnatal growth; 17 with discordant effects and nine with concordant effects. Genetic variants in the IGF-axis appear to play a significant role in antenatal and postnatal growth. Further replication and new analytic methods are required in order to better understand this key metabolic pathway integrating biologic knowledge about the interaction between IGF-axis components.

16.
Artigo em Inglês | MEDLINE | ID: mdl-22646085

RESUMO

The copper(II) complexes with ciprofloxacin (CFLH), levofloxacin (LFLH), norfloxacin (NFLH), and neutral bidentate ligands have been synthesized and characterized. The complexes have been evaluated for their antibacterial activity against selective species. Complexes have been also checked for their interacting behavior with DNA, and were found to have two different modes of interaction, classical and partial intercalation. Tested complexes were found to be better antioxidants with their IC(50) values ranging from 0.51 to 0.97 µM.


Assuntos
Materiais Biomiméticos/síntese química , Materiais Biomiméticos/farmacologia , Cobre/química , Desoxirribonucleases/metabolismo , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Superóxido Dismutase/metabolismo , Absorção , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Técnicas de Química Sintética , DNA/metabolismo , Ligantes , Compostos Organometálicos/química , Compostos Organometálicos/metabolismo , Viscosidade
17.
Pharmacogn Rev ; 4(7): 42-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22228940

RESUMO

Mangifera indica, commonly used herb in ayurvedic medicine. Although review articles on this plant are already published, but this review article is presented to compile all the updated information on its phytochemical and pharmacological activities, which were performed widely by different methods. Studies indicate mango possesses antidiabetic, anti-oxidant, anti-viral, cardiotonic, hypotensive, anti-inflammatory properties. Various effects like antibacterial, anti fungal, anthelmintic, anti parasitic, anti tumor, anti HIV, antibone resorption, antispasmodic, antipyretic, antidiarrhoeal, antiallergic, immunomodulation, hypolipidemic, anti microbial, hepatoprotective, gastroprotective have also been studied. These studies are very encouraging and indicate this herb should be studied more extensively to confirm these results and reveal other potential therapeutic effects. Clinical trials using mango for a variety of conditions should also be conducted.

18.
Bioorg Med Chem Lett ; 18(24): 6494-500, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18993070

RESUMO

Five-coordinated oxovanadium(IV) complexes with ciprofloxacin and various uninegative bidentate amino acids have been prepared. The structure of complexes has been investigated using spectral, physicochemical, mass spectroscopy, and elemental analyses. The antimicrobial activities (MIC) of the complexes, ligands, metal salt, and some standard drugs have been evaluated using the doubling dilution technique against Staphylococcus aureus, Bacillus subtilis, Serratia marcescens (gram-positive), and Pseudomonas aeruginosa, and Escherichia coli (gram-negative) bacteria. The result shows the significant increase in the antibacterial activity of the ligand, metal, and ciprofloxacin on complexation. The interaction of the complexes with pBR322 DNA has been investigated using spectroscopic, gel electrophoresis, and viscometric techniques. This shows that the complexes can bind to pBR322 DNA by the intercalative mode. The superoxide dismutase-like activity of the complexes has been determined.


Assuntos
Anti-Infecciosos/síntese química , Ciprofloxacina/química , DNA/química , Vanadatos/química , Anti-Infecciosos/farmacologia , Bacillus subtilis/metabolismo , Química Farmacêutica/métodos , Escherichia coli/metabolismo , Ligantes , Espectrometria de Massas/métodos , Metais/química , Modelos Químicos , Pseudomonas aeruginosa/metabolismo , Serratia marcescens/metabolismo , Staphylococcus aureus/metabolismo , Termogravimetria
19.
J Postgrad Med ; 52(1): 19-22, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16534159

RESUMO

BACKGROUND: Ultrasonography is an important tool for evaluating the posterior segment in eyes with opaque media. AIM: To study the incidence of posterior segment pathology in eyes with advanced cataract and to see whether certain features could be used as predictors for an abnormal posterior segment on ultrasound. SETTING: Tertiary care hospital in South India. METHODS AND MATERIALS: In this prospective study conducted over a 6-month period, all eyes with dense cataracts precluding visualization of fundus underwent assessment with ultrasound. Presence of certain patient and ocular "risk" factors believed to be associated with a higher incidence of abnormal posterior segment on ultrasound were looked for and the odds ratio (OR) for posterior segment pathology in these eyes was calculated. RESULTS: Of the 418 eyes assessed, 36 eyes (8.6%) had evidence of posterior segment pathology on ultrasound. Retinal detachment (17 eyes; 4.1%) was the most frequent abnormality detected. Among patient features, diabetes mellitus (OR= 4.9, P= 0.003) and age below 50 years (OR= 15.4, P= 0.001) were associated with a high incidence of abnormal ultrasound scans. In ocular features, posterior synechiae (OR= 20.2, P= 0.000), iris coloboma (OR= 34.6, P= 0.000), inaccurate projection of rays (OR= 15.1, P= 0.002), elevated intraocular pressure (OR= 15.1, P= 0.004) and keratic precipitates (OR= 22.4, P= 0.004) were associated with high incidence of posterior segment pathology. Only four eyes (1.5%) without these features had abnormal posterior segment on ultrasonography. CONCLUSIONS: Certain patient and ocular features are indicative of a high risk for posterior segment pathology and such patients should be evaluated by ultrasonography prior to cataract surgery. In the absence of these risk factors, the likelihood of detecting abnormalities on preoperative ultrasonography in eyes with advanced cataracts is miniscule.


Assuntos
Catarata/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Catarata/epidemiologia , Catarata/patologia , Extração de Catarata , Feminino , Humanos , Incidência , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Cuidados Pré-Operatórios/métodos , Estudos Prospectivos , Fatores de Risco , Ultrassonografia
20.
Ophthalmic Res ; 37(3): 117-22, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15746568

RESUMO

PURPOSE: To compare the in vitro activity of gatifloxacin with that of other topical antibiotics against fresh bacterial isolates from various types of human ocular infections. METHODS: A total of 498 strains of ocular bacterial isolates were tested for their susceptibility to gatifloxacin, ofloxacin, ciprofloxacin, norfloxacin, gentamicin, tobramycin, neomycin, chloramphenicol, erythromycin, tetracycline and amikacin. RESULTS: Ninety-nine percent of gram-positive and 92% of gram-negative bacterial strains were found to be susceptible in vitro to gatifloxacin, whereas lower percentages of gram-positive and gram-negative bacteria were found to be susceptible to other antibiotics. CONCLUSIONS: In vitro, gatifloxacin exhibits good activity against various bacterial species isolated from different ocular sites. This requires corroboration in the clinical setting.


Assuntos
Anti-Infecciosos Locais/farmacologia , Fluoroquinolonas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Infecções Oculares Bacterianas/microbiologia , Gatifloxacina , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Soluções Oftálmicas/farmacologia
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