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1.
Community Dent Health ; 41(1): 20-26, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-37988670

RESUMO

OBJECTIVE: To investigate patients' preference for extraction or preservation for toothache and hypothetical anterior tooth pain along with the specific reason for their choice. BASIC RESEARCH DESIGN: Cross-sectional analytical semi-structured interview study. PARTICIPANTS: A sample of 703 adult dental outpatients visiting secondary and tertiary government health centres with toothache due to dental caries in Eastern India. MAIN OUTCOME MEASURES: Patients preferring restorative or extraction services for toothache, specific reason, and socio-demographic background factors for anterior and posterior teeth. RESULTS: Half (50.1%) choose preservation for present toothache and 79.9% for hypothetical front tooth pain. Immediate relief from toothache for extraction and the motive to preserve natural teeth for preservation were the main reasons expressed. In logistic regression, participants preferring extraction were more likely to be aged 25-34 years (OR = 1.94), 55+ years (OR=33.32), have primary and below education level (OR=1.99), have had a previous extraction (OR=1.99) and be unaware of preservation options (OR=2.34). For assumed anterior tooth pain, those between 25-34 years (OR=0.39) were more likely to choose preservation. Participants with primary and below education levels (OR=1.99) and unaware of preservation options (OR=1.95) chose extraction of the front tooth irrespective of their choice of treatment for the present toothache. CONCLUSION: Notable differences between the choices to preserve or extract a posterior tooth were not found. There was greater preference towards preserving anterior teeth. Future research should identify additional barriers to the preference and utilization of restorative services.


Assuntos
Cárie Dentária , Adulto , Humanos , Odontalgia/terapia , Extração Dentária , Preferência do Paciente , Estudos Transversais
2.
Ageing Int ; 48(1): 41-77, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34465930

RESUMO

Today's working population is expected to experience a longer and healthier life than previous generations did. This, combined with a currently shrinking workforce, means the participation of older adults in the labor market is expected to positively contribute to national economic and social development. Policymakers have therefore implemented a series of reforms to motivate and encourage both employers and employees to embrace the prospect of an aging workforce and to respond to the associated challenges of such a demographic change in the workplace. This paper aims to provide an overview of recent policy initiatives in this context and to identify the role of technology in major international initiatives in overcoming the key challenges faced by developed countries. We have conducted a scoping review to obtain large volumes of peer-reviewed and gray literature. Our findings suggest that the stakeholders (researchers, government agencies, employers, and communities) are not only aware of the current issues relating to the aging population but also understand the importance of policies in terms of retaining older people in the workforce. In particular, our results indicate that technology, in both the public and private sectors, can be leveraged as a tool to facilitate older adults' participation in the workforce.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36232222

RESUMO

Evidence suggests that prolonged blue-light exposure can impact vision; however, less is known about its impact on non-visual higher-order functions in the brain, such as learning and memory. Blue-light-blocking lenses (BBLs) claim to reduce these potential impacts. Hence, we assessed structural and functional hippocampal alterations following blue-light exposure and the protective efficacy of BBLs. Male Wistar rats were divided into (n = 6 in each group) normal control (NC), blue-light exposure (LE), and blue-light with BBLs (Crizal Prevencia, CP and DuraVision Blue, DB) groups. After 28 days of light exposure (12:12 light: dark cycle), rats were trained for the Morris water maze memory retention test, and brain tissues were sectioned for hippocampal neuronal analysis using Golgi and Cresyl violet stains. The memory retention test was significantly delayed (p < 0.05) in LE compared with DB groups on day 1 of training. Comparison of Golgi-stained neurons showed significant structural alterations, particularly in the basal dendrites of hippocampal neurons in the LE group, with BBLs significantly mitigating these structural changes (p < 0.05). Comparison of Cresyl-violet-stained neurons revealed significantly (p < 0.001) increased degenerated hippocampal neurons in LE rats, with fewer degenerated neurons in the CP lens group for CA1 neurons (p < 0.05), and for both CP and DB groups (p < 0.05) for CA3 neurons. Thus, in addition to documented effects on visual centers, high-level blue-light exposure also results in degeneration in hippocampal neurons with associated behavioral deficits. These changes can be partially ameliorated with blue-light-blocking lenses.


Assuntos
Hipocampo , Roedores , Animais , Dendritos , Masculino , Neurônios , Ratos , Ratos Wistar
4.
Eur J Ageing ; 16(3): 337-361, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31543728

RESUMO

The ageing of populations worldwide has implications for workforces in developed countries, and labour shortages have increasingly become a political concern. Governments in developed countries have responded by increasing the retirement age as a strategy for overcoming the fall in labour supply. Using bibliometric techniques, we reviewed 122 articles published between 1990 and 2018 to examine the effectiveness of the strategy in addressing the labour shortages and, in particular, to identify the factors that contribute positively to maintaining worker participation within an ageing workforce at an organizational level. The results identified five organizational factors that support continued participation: health, institutions, human resource management, human capital and technology tools. Employers will increasingly need to develop "age-friendly" workplaces and practices if they are to recruit and retain older workers.

5.
J Med Syst ; 42(10): 193, 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30206721

RESUMO

Meditation improves positivity in behavioral as well as psychological changes, which are brought elucidated by knowing neuro-physiological consequences of meditation. In the field of cognitive science, neuroscience and physiological research, Electroencephalogram (EEG) is extensively utilized. The primary tasks of EEG signal analysis is to identify the noisy signal as well as enormous data that create signal processing and subsequent analysis. Beforehand any analysis of the EEG signal, the obtained raw signal must be preprocessed for eliminating undesirable artifacts as well as horrible noise. With the aim of resolving this issue, in this research, raw signals are preprocessed with the help of Band-Pass Filter (BPF) for noise removal method. Instead, in adaptive Sliding Window with Fuzzy C Means Clustering (SW-FCM) segmentation is presented, which precisely as well as automatically segments the signals. So as to analyze the accuracy, five features such as electroencephalography alpha spectrum, frequency of the main peak, Amplitude of the main peak, Higher Order Crossing (HOC), and wavelet features are used as the evaluating variables. Lastly to assess the meditation experience with Fuzzy Kernel least square Support Vector Machine (FKLSSVM) classifier, the presented method with a cross-sectional analysis is utilized. These two classifiers are utilized for meditation experience classification by utilizing an individual feature vector values from equivalent EEG signals. The dataset samples are gathered from Open source Brain-Computer Interface (Open BCI) platform. Outcomes attained are matched up for diverse techniques for identifying as well as for classifying signal segments features using MATLAB. Presented classifiers of the meditation process validate quick interpretation methods that differentiate meditation experience and valuable performance related to artificial approaches for the big-data analysis.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Meditação , Máquina de Vetores de Suporte , Algoritmos , Estudos Transversais , Humanos , Processamento de Sinais Assistido por Computador
6.
Mol Psychiatry ; 23(9): 1868-1877, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-28948967

RESUMO

Hoxb8 mutant mice exhibit compulsive grooming and hair removal dysfunction similar to humans with the obsessive-compulsive disorder (OCD)-spectrum disorder, trichotillomania. As, in the mouse brain, the only detectable cells that label with Hoxb8 cell lineage appear to be microglia, we suggested that defective microglia cause the neuropsychiatric disorder. Does the Hoxb8 mutation in microglia lead to neural circuit dysfunctions? We demonstrate that Hoxb8 mutants contain corticostriatal circuit defects. Golgi staining, ultra-structural and electrophysiological studies of mutants reveal excess dendritic spines, pre- and postsynaptic structural defects, long-term potentiation and miniature postsynaptic current defects. Hoxb8 mutants also exhibit hyperanxiety and social behavioral deficits similar to mice with neuronal mutations in Sapap3, Slitrk5 and Shank3, reported models of OCD and autism spectrum disorders (ASDs). Long-term treatment of Hoxb8 mutants with fluoxetine, a serotonin reuptake inhibitor, reduces excessive grooming, hyperanxiety and social behavioral impairments. These studies provide linkage between the neuronal defects induced by defective Hoxb8-microglia and neuronal dysfunctions directly generated by mutations in synaptic components that result in mice, which display similar pathological grooming, hyperanxiety and social impairment deficits. Our results shed light on Hoxb8 microglia-driven circuit-specific defects and therapeutic approaches that will become essential to developing novel therapies for neuropsychiatric diseases such as OCD and ASDs with Hoxb8-microglia being the central target.


Assuntos
Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/fisiologia , Transtorno Obsessivo-Compulsivo/genética , Animais , Comportamento Animal/fisiologia , Cerebelo/fisiologia , Modelos Animais de Doenças , Asseio Animal/fisiologia , Proteínas de Membrana/genética , Camundongos , Microglia/fisiologia , Rede Nervosa/fisiologia , Proteínas do Tecido Nervoso/genética , Neurônios/fisiologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Sinapses/patologia
7.
J Photochem Photobiol B ; 178: 33-39, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29101871

RESUMO

The present study reports, novel and greener method for synthesis of gold nanoparticles (AuNPs) using 5,7-dihydroxy-6-metoxy-3',4'methylenedioxyisoflavone (Dalspinin), isolated from the roots of Dalbergia coromandeliana was carried out for the first time. The synthesized gold nanoparticles were characterized by UV-Vis spectroscopy, high resolution transmission electron microscopy (HR-TEM), selected area electron diffraction (SAED), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The observed surface plasmon resonance (SPR) at 532nm in the UV-Vis absorption spectrum indicates the formation of gold nanoparticles. The powder XRD and SAED pattern for synthesized gold nanoparticles confirms crystalline nature. The HR-TEM images showed that the AuNPs formed were small in size, highly monodispersed and spherical in shape. The average particle sizes of the AuNPs are found to be ~10.5nm. The prepared AuNPs were found to be stable for more than 5months without any aggregation. The catalytic degradation studies of the synthesized AuNPs towards degradation of congo red and methyl orange, showed good catalytic in the complete degradation of both the dyes. The reduction catalyzed by gold nanoparticles followed the pseudo-first order kinetics, with a rate constant of 4.5×10-3s-1 (R2=0.9959) and 1.7×10-3s-1 (R2=0.9918) for congo red (CR) and methyl orange (MO), respectively.


Assuntos
Compostos Azo/química , Vermelho Congo/química , Poluentes Ambientais/química , Ouro/química , Nanopartículas Metálicas/química , Nanotecnologia , Catálise , Técnicas de Química Sintética , Química Verde
8.
Mol Psychiatry ; 2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-29180671

RESUMO

This corrects the article DOI: 10.1038/mp.2017.180.

9.
Chem Commun (Camb) ; 53(85): 11709-11712, 2017 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-29022631

RESUMO

The applicability of C-H functionalization to medicinally important 2-pyridyl-based N-heterocycles suffers from severe challenges owing to the high Lewis basicity of the N-atom. This arrests catalytic activity and yields undesirable positional selectivity due to preferential chelate formation. In this regard, we report a novel palladium(ii)-catalyzed arylation strategy on multiple-N-containing pyridazines by over-riding the functionalization due to a chelated palladacycle. We report a regioselective mono-arylation at the 8-position of diphenyl azolopyridazines without any ortho-C-H activation on the proximal phenyl groups. This methodology presents a broad arylation scope with uncompromised yield and positional selectivity, including the heteroarylation of N-heterocycles, which is an unprecedented feat for these types of molecules.

11.
Artigo em Inglês | MEDLINE | ID: mdl-25804509

RESUMO

Two sensitizers based on amino acids coupled with perylene moiety having absorption in the visible region have been designed and their interaction with doped and undoped TiO2 for the application of dye sensitized solar cells (DSSCs) has been studied. The synthesized compounds PDI-PA and PDI-AA were characterized using (1)H and (13)C NMR, Mass and FT-IR spectroscopic techniques. The optical properties and lifetime measurements of the sensitizers were analyzed using various solvents with different polarity. The solvatochromism effect was studied using Lippert-Mataga plot. The electrochemical studies of both dyes were investigated in DMF with various scan rate ranging from 200 to 1000 mV s(-1). Colloidal doped and undoped TiO2 was prepared and characterized by using absorption measurements. Binding ability of the sensitizers with the nanoparticles was studied through absorption, fluorescence quenching, cyclic voltammetry and FT-IR measurements. Results obtained from all the above analysis suggest the mode of quenching may be static. The binding constant values were calculated using Kamat-Fox equation indicates the binding behavior of the sensitizers with the nanoparticles. The fluorescence quenching was mainly attributed to electron transfer from the excited state of PDI's to the conduction band of colloidal semiconductors. The electron transfer mechanism was explained based on the Rehm-Weller equation as well as the energy level diagram.


Assuntos
Perileno/análogos & derivados , Perileno/química , Titânio/química , Coloides , Espectroscopia de Ressonância Magnética
12.
Br J Surg ; 102(6): 700-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25809125

RESUMO

BACKGROUND: To determine a true denominator of worldwide surgical need, it is imperative to include estimations at a population-based level, to capture those individuals unable to access surgical care. This study was designed to validate the Surgeons OverSeas Assessment of Surgical need (SOSAS) tool with the addition of a visual physical examination, and describe the prevalence of surgical conditions, deaths possibly averted with access to surgical care, and the number of surgical procedures performed annually, in Nepal. METHODS: The SOSAS tool, developed to measure the prevalence of surgical conditions at a population level and used in two African countries, was employed. Fifteen of the 75 districts of Nepal were chosen proportional to population. Responses were recorded for the head of the household for demographic information and recalled deaths, and two randomly selected household members underwent a verbal head-to-toe interview for surgical conditions and a visual physical examination by a trained physician. RESULTS: A total of 1350 households were surveyed (2695 respondents). Observed agreement between the verbal response and physical examination findings was 94·6 per cent. Some 10·0 (95 per cent c.i. 8·9 to 11·2) per cent of respondents had a current condition requiring surgical care and 23 per cent of deaths may have been averted with proper access to surgical care. An estimated 291·8 major operations per 100 000 population are performed annually in Nepal. CONCLUSION: The visual physical examination component validated the SOSAS tool, and justified the estimates of previous studies in Sierra Leone and Rwanda. These data provide insights into the health needs of Nepal and provide evidence to develop surgical programmes, assist with monitoring and evaluation, and help with advocacy for increased resources in Nepal.


Assuntos
Países em Desenvolvimento , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Pesquisa sobre Serviços de Saúde/métodos , Avaliação das Necessidades/organização & administração , Procedimentos Cirúrgicos Operatórios/estatística & dados numéricos , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Nepal/epidemiologia , Procedimentos Cirúrgicos Operatórios/normas , Taxa de Sobrevida/tendências
13.
Can J Microbiol ; 61(4): 297-306, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25768053

RESUMO

Electroplating industries in Madurai city produce approximately 49,000 L of wastewater and 1200 L of sludge every day revealing 687-5569 ppm of nickel (Ni) with other contaminants. Seventeen Ni-tolerant bacterial strains were isolated from nutrient-enriched effluents. Among them one hyper Ni accumulating strain was scored and identified as Bacillus cereus VP17 on the basis of morphology, biochemical tests, 16S rDNA gene sequencing, and phylogenetic analysis. Equilibrium data of Ni(II) ions using the bacterium as sorbent at isothermal conditions (37 °C) and pH 6 were best adjusted by Langmuir (R(2) = 0.6268) and Freundlich models (R(2) = 0.9505). Experimental validation reveals Ni sorption takes place on a heterogeneous surface of the biosorbent, and predicted metal sorption capacity is 434 ppm. The pseudo-second-order kinetic model fitted the biosorption kinetic data better than the pseudo-first-order kinetic model (R(2) = 0.9963 and 0.3625). Scanning electron microscopy, energy dispersive X-ray, and Fourier transform infrared spectroscopy studies of the bacterial strain with and without Ni(II) ion reveals the biosorption mechanism. The results conclude possibilities of using B. cereus VP17 for Ni bioremediation.


Assuntos
Bacillus cereus/isolamento & purificação , Bacillus cereus/metabolismo , Níquel/metabolismo , Esgotos/microbiologia , Águas Residuárias/microbiologia , Adsorção , Bacillus cereus/classificação , Bacillus cereus/genética , Biodegradação Ambiental , Galvanoplastia , Índia , Cinética , Níquel/química , Filogenia , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Transbound Emerg Dis ; 62(3): 264-71, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23890104

RESUMO

In present investigation, etiopathological characterization of upper gastrointestinal tract (GIT) tumours of cattle and buffaloes was undertaken. A total of 27 GIT wart-like lesions in rumen, reticulum, mouth and oesophagus of cattle and buffaloes revealed the presence of small nodular to larger spherical or slender growths with thin base present on mucosa and ruminal pillar. Histopathologically, these cases were diagnosed as fibropapilloma/papilloma. This is the first world record on ruminal papillomatosis in buffaloes. Ruminal warts of cattle and buffaloes revealed the presence of BPV-5, -1 & -2, which is the first report of presence of these BPVs in the ruminal warts from India. Quantitative real-time PCR revealed that DNA samples of different GIT wart-like lesions contained varying amount of BPV DNA copy numbers. Immunohistochemistry revealed that the PCNA and Ki67 immunopositivity was present in the basal and spinosum layer of the fibropapilloma/papilloma, indicating these as the cellular proliferation site. In conclusion, the present investigation revealed that BPV-5, -1 & -2 are associated with certain ruminal wart-like lesions/growths in cattle and buffaloes, and the basal and spinosum layer of the ruminal fibropapilloma/papilloma were cellular proliferation sites.


Assuntos
Doenças dos Bovinos/virologia , Gastroenteropatias , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/veterinária , Verrugas/veterinária , Animais , Búfalos , Bovinos , DNA Viral/genética , DNA Viral/isolamento & purificação , Gastroenteropatias/veterinária , Gastroenteropatias/virologia , Imuno-Histoquímica , Índia , Papillomaviridae/genética , Reação em Cadeia da Polimerase/veterinária , Reação em Cadeia da Polimerase em Tempo Real , Trato Gastrointestinal Superior/patologia , Trato Gastrointestinal Superior/virologia , Verrugas/virologia
15.
Post Reprod Health ; 20(2): 62-68, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24879744

RESUMO

Premature menopause is characterized by amenorrhea, elevated gonadotropin levels and sex steroid deficiency occurring in women below 40 years of age. Heterogeneity of premature ovarian failure is reflected by various causes, both spontaneous and iatrogenic. X chromosomal abnormalities remain the main cause of primary ovarian insufficiency. Women with primary ovarian insufficiency present with amenorrhea, irregular cycles, signs of estrogen deficiency and infertility. They are at increased risk for non-communicable diseases such as, cardiovascular disease, Alzheimer's disease, and osteoporosis. Management includes use of menopausal hormone therapy till the age of natural menopause and customized as per the needs. In women having fertility issues, IVF with donor oocytes remains the treatment of choice with the best results. With advances in assisted reproductive technologies, cryopreservation of oocytes/embryos should be utilized, whenever impending primary ovarian insufficiency is anticipated either due to therapy or biological reasons.

16.
J Photochem Photobiol B ; 127: 212-22, 2013 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-24061160

RESUMO

A series of imidazole derivatives connected with pyridine moiety through phenyl groups were synthesized by using Suzuki coupling followed by multicomponent cyclization reaction. Results obtained from spectroscopic ((1)H NMR, (13)C NMR, Mass) and single crystal X-ray diffraction analysis of synthesized compound was in very good agreement with its chemical structure. UV-Vis and fluorescence studies in various solvents with different polarity demonstrated that these compounds were sensitive to the polarity of the microenvironment. In addition, multi linear regression analysis based on Kamlet-Taft and Catalán new four parameter solvent scale results in solvatochromism and was mainly influenced by solvent polarisability and dipolarity of the environment. The electrochemical stability of the compounds was also studied by cyclic voltammetry. An excellent fluorescent nature with high quantum efficiency of the compounds was successfully utilized to probe the bacteria by using fluorescence microscopy. In addition, the antibacterial and antifungal activity of these compounds were also studied in vitro by the disk diffusion assay against one Gram-positive, three Gram-negative bacteria and Candida albicans. MPBI showed relatively good inhibitory action against Gram-negative bacteria and TPBI against Gram-positive bacteria and 3PBI against C. albicans.


Assuntos
Imidazóis/síntese química , Imidazóis/farmacologia , Imagem Óptica/métodos , Piridinas/química , Solventes/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Técnicas de Química Sintética , Cristalografia por Raios X , Ciclização , Eletroquímica , Fungos/efeitos dos fármacos , Imidazóis/química , Modelos Lineares , Modelos Moleculares , Conformação Molecular
17.
Colloids Surf B Biointerfaces ; 101: 74-82, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22796774

RESUMO

This study was undertaken to evaluate the antioxidant potential of an aqueous extract from Merremia emarginata leaves because this plant has a very high flavonoid and phenol content. The in vitro antioxidant activity was measured by diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid (ABTS), superoxide anion scavenging assay and lipid peroxidation activity; the total reducing capability of the plant extract indicates that this plant is a source for natural antioxidants. Furthermore, we investigated thio glycolic acid-capped cadmium telluride quantum dots (TGA-CdTe QDs) as fluorescent probes to study the antioxidant activity of the M. emarginata extract through fluorescence quenching. The antimicrobial activity was also investigated using a disc diffusion method and fluorescence microscopy. The TGA-CdTe QDs and M. emarginata complex could provide antimicrobial activity through a reactive oxygen species pathway and/or microbial endocytosis through an electrostatic attraction. Based on our findings, we suggest that the QDs act as potential probes for the in vitro antioxidant and antimicrobial activities. In addition, their cooperative effect with the plant extract indicates that QDs could be used as nanocarriers to enhance the antimicrobial capability. Further in vivo studies on the photolabelling of antioxidants with QDs will provide insights into the mechanistic pathways of secondary metabolites against various degenerative diseases.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Compostos de Cádmio/química , Convolvulaceae/química , Pontos Quânticos , Telúrio/química , Tioglicolatos/química , Benzotiazóis/química , Compostos de Bifenilo/química , Difusão , Escherichia coli/efeitos dos fármacos , Flavonoides/análise , Indicadores e Reagentes , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanopartículas , Fenóis/análise , Picratos/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Espectrometria de Fluorescência , Ácidos Sulfônicos/química , Superóxidos/química
18.
J Pharm Biomed Anal ; 56(4): 721-7, 2011 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-21840668

RESUMO

Collision-induced dissociation (CID) mass spectra of a few haloaniline isomers, (chloroanilines, dichloroanilines, difluoroanilines, chloro-fluoroanilines and bromo-fluoroanilines) were characterized. The mass spectral behaviour of difluoroanilines was different from those of the corresponding regioisomers of the other haloanilines. For all ortho regioisomers except difluoroanilines, CID mass spectra resulted in hydrogen halide as well as halogen radical loss. In the case of difluoroanilines, peaks corresponding to hydrogen fluoride loss were observed during the same process. Meta and para-haloanilines have the tendency to lose either ammonia or halogen radicals. Six regioisomers of dichloroanilines were subjected to hydrogen/deuterium exchange experiments in solution to determine the CID fragmentation pathways. From the experimental results we propose two fragmentation pathways for the dicholoroanilines: (a) formation of aza-biheterocyclic intermediate and (b) via heterolytic hydrogen transfer from the charged center. The demonstrated unique characteristics in CID mass fragmentation of haloanilines may be useful in identification and differentiation of isomers as impurities during chemical process development. A good use of the ortho effect is the significant differentiation between 2-chloro-4-fluoroaniline and 4-chloro-2-fluoroaniline by CID mass spectra.


Assuntos
Compostos de Anilina/análise , Mutagênicos/análise , Compostos de Anilina/química , Compostos de Anilina/metabolismo , Dano ao DNA , Deutério/química , Deutério/metabolismo , Humanos , Isomerismo , Espectrometria de Massas , Mutagênicos/química , Mutagênicos/metabolismo , Prótons , Software
19.
Indian J Sex Transm Dis AIDS ; 30(1): 37-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21938113

RESUMO

Varicella zoster virus (VZV) infections are known to be atypical and severe in immunocompromised patients. An eight-year-old girl presented with extremely painful, atypical skin lesions and features of meningitis and pneumonitis. On investigation, she was found to be human immunodeficiency virus (HIV) infected, with very low CD4 count. A diagnosis of 'progressive varicella syndrome' was made, and the child was started on antiretroviral therapy and IV acyclovir. This resulted in a complete resolution of all the clinical features. However, the skin lesions promptly relapsed when acyclovir was withdrawn. Oral Acyclovir was started, and had to be continued to keep the disease under control.

20.
Neuroscience ; 154(1): 390-6, 2008 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-18304741

RESUMO

Sensory experiences contribute to the development and specialization of signal processing capacities in the mammalian auditory system during a "critical period" of postnatal development. Earlier studies have shown that passive exposure to tonal stimuli during this postnatal epoch induces a large-scale expansion of the representations of those stimuli within the primary auditory cortex (A1) [Zhang LI, Bao S, Merzenich MM (2001) Persistent and specific influences of early acoustic environments on primary auditory cortex. Nat Neurosci 4:1123-1130]. Here, we show that exposing rat pups through the normal critical period epoch and beyond to continuous, un-modulated, moderate-level tones induces no such representational distortion, and in fact disrupts the normal development of frequency response selectivity and tonotopicity all across area A1. The area of cortex responding selectively to continuously exposed sound frequencies was actually reduced, when compared with rats reared in normal environments. Strong exposure-driven plasticity characteristic of the critical period could be induced well beyond the normal end of the critical period, by simply modulating the tonal stimulus. Thus, continuous tone exposure, like continuous noise exposure [Chang EF, Merzenich MM (2003) Environmental noise retards auditory cortical development. Science 300:498-502], ineffectively induces critical period plasticity, and indefinitely blocks the closure of a normally-brief critical period window. These findings again demonstrate the crucial role of temporally structured inputs for inducing the progressive cortical maturational changes that result in the closure of the critical period window.


Assuntos
Córtex Auditivo/citologia , Vias Auditivas/fisiologia , Mapeamento Encefálico , Período Crítico Psicológico , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Estimulação Acústica/métodos , Fatores Etários , Animais , Animais Recém-Nascidos , Feminino , Masculino , Ruído/efeitos adversos , Psicofísica , Ratos
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