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1.
Trans Indian Natl Acad Eng ; 5(2): 289-294, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-38624417

RESUMO

Chitra Disinfection Gateway is meant for the decontamination of personnel entering a cleaner private space from a public space. This is equipped with an arrangement for generating hydrogen peroxide mist and ultraviolet rays. Hydrogen peroxide mist will decontaminate clothes, hands and the bags a person carries. The ultraviolet system will decontaminate the chamber once the person has moved out. The system is controlled electronically by sensors and actuators. The sensors fixed in the chamber detect the entry of a person and initiates the hydrogen peroxide atomization process. The person is required to walk through the chamber. When the person exits the chamber, the system will put off the hydrogen peroxide atomization system and will turn on the UV lamp inside the chamber to decontaminate it. The ultraviolet system will be ON for a predefined time and after the process, the next person can enter the walkway. The whole process takes a maximum of 40 s. The safety and efficacy of the system have been validated experimentally through both in vivo and in vitro studies.

2.
Proc Inst Mech Eng H ; 231(8): 758-765, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28395636

RESUMO

Average age group of heart valve replacement in India and most of the Third World countries is below 30 years. Hence, the valve for such patients need to be designed to have a service life of 50 years or more which corresponds to 2000 million cycles of operation. The purpose of this study was to assess the structural performance of the TTK Chitra tilting disc heart valve model TC2 and thereby address its durability. The TC2 model tilting disc heart valves were assessed to evaluate the risks connected with potential structural failure modes. To be more specific, the studies covered the finite element analysis-based fatigue life prediction and accelerated durability testing of the tilting disc heart valves for nine different valve sizes. First, finite element analysis-based fatigue life prediction showed that all nine valve sizes were in the infinite life region. Second, accelerated durability test showed that all nine valve sizes remained functional for 400 million cycles under experimental conditions. The study ensures the continued function of TC2 model tilting disc heart valves over duration in excess of 50 years. The results imply that the TC2 model valve designs are structurally safe, reliable and durable.


Assuntos
Próteses Valvulares Cardíacas , Análise de Elementos Finitos , Desenho de Prótese , Falha de Prótese , Fatores de Tempo
3.
Methods Mol Biol ; 1391: 113-23, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27108313

RESUMO

Here we describe an efficient micropropagation protocol for Stevia rebaudiana Bertoni. We present experiments carried out to optimize the suitable media for in vitro shoot multiplication and root induction and to study the effect of culture vessel on shoot multiplication. Among all different media tested for in vitro shoot multiplication, hormone-free liquid medium is most suitable. The highest number of nodes per shoot (5.4) and length of shoot (4.76 cm) at 4 weeks after subculturing are observed when single node explants are placed on modified MS medium supplemented with 1 % sucrose and 0.7 % agar. The highest response of multiplication rate (9.56) is observed on half strength of macroelement of MS with full strength of microelement of MS and 170 mg/l KH2PO4, and 185 mg/l MgSO4 in plastic growth container. Further, RAPD marker analysis of in vitro-raised plants maintained their clonal fidelity and true-to-type without showing any somaclonal variation.


Assuntos
Brotos de Planta/crescimento & desenvolvimento , Stevia/crescimento & desenvolvimento , Ágar/metabolismo , Biomassa , Meios de Cultura/metabolismo , Técnicas de Cultura/métodos , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Melhoramento Vegetal/métodos , Brotos de Planta/genética , Brotos de Planta/metabolismo , Reação em Cadeia da Polimerase/métodos , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos , Stevia/genética , Stevia/metabolismo , Sacarose/metabolismo
4.
Neurochem Int ; 90: 193-203, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26363090

RESUMO

Vascular bed calcification is a common feature of ends stage renal disease that may lead to a complication in cardiovascular and cerebrovascular beds, which is a promoting cause of myocardial infarction, stroke, dementia and aneurysms. Sodium thiosulfate (STS) due to its multiple properties such as antioxidant and calcium chelation has been reported to prevent vascular calcification in uremic rats, without mentioning its impact on cerebral function. Moreover, the previous studies have not explored the effect of STS on the mitochondrial dysfunction, one of the main pathophysiological features associated with the disease and the main site for STS metabolism. The present study addresses this limitation by using a rat model where 0.75% adenine was administered to induce vascular calcification and 400 mg/kg b wt. of STS was given as preventive and curative agent. The blood and urine chemistries along with histopathology of aorta confirms the renal protective effect of STS in two modes of administration. The brain oxidative stress assessment was made through TBARS level, catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, found to be in the near normal level. STS administration not only reduced the mitochondrial oxidative stress (measured by TBARS, SOD, GPx and CAT) but also preserved the mitochondrial respiratory enzyme activities (NADH dehydrogenase, Succinate dehydrogenase and Malate dehydrogenase) and its physiology (measured by P/O ratio and RCR). In fact, the protective effect of STS was prominent, when it was administered as a curative agent, where low H2S and high thiosulfate level was observed along with low cystathionine ß synthase activity, confirms thiosulfate mediated renal protection. In conclusion, STS when given after induction of calcification is protective to the brain by preserving its mitochondria, compared to the treatment given concomitantly.


Assuntos
Adenina/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tiossulfatos/farmacologia , Calcificação Vascular/tratamento farmacológico , Animais , Antioxidantes/farmacologia , Catalase/metabolismo , Modelos Animais de Doenças , Glutationa Peroxidase/metabolismo , Rim/efeitos dos fármacos , Rim/fisiologia , Masculino , Oxirredução/efeitos dos fármacos , Ratos Wistar , Calcificação Vascular/induzido quimicamente
5.
BMJ Open ; 1(1): e000071, 2011 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-22021749

RESUMO

BACKGROUND: Strong proof-of-principle for utilisation of diffuse reflectance spectroscopy, a non-invasive tool for early detection of malignant changes, has emerged recently. The potential of this technique in distinguishing normal tissue from hyperplastic and dysplastic tissues was explored. METHODS: Diffuse reflectance (DR) spectra in the 400-700 nm region were obtained from the buccal mucosa of 96 patients and 34 healthy volunteers. The DR spectral data were compared against the gold standard biopsy and histopathology results. A principal-component analysis was performed for dimensional reduction in the normalised spectral data with linear discriminant analysis as the classifying technique. The receiver operator characteristic curve technique was employed for evaluating the performance of the diagnostic test. RESULTS: DR spectral features for different lesions, such as normal/healthy, hyperplastic, dysplastic and squamous cell carcinoma (SCC), varied significantly according to the intensity of oxygenated haemoglobin absorption. While the classification based on discriminant scores provided an overall sensitivity of 98.5% and specificity of 96.0% for distinguishing SCC from dysplasia, they were 100.0% and 95.0%, respectively, for distinguishing dysplasia from hyperplasia. Similarly, the analysis yielded a sensitivity of 95.0% and specificity of 100.0% for distinguishing hyperplasia from healthy tissue. The areas under the receiver operator characteristic curves were 0.98 (95% CI 0.95 to 1.00) and 0.95 (95% CI 0.90 to 1.00) for distinguishing dysplasia from SCC and hyperplasia from dysplasia, respectively. CONCLUSION: DR spectral data efficiently discriminate healthy tissue from oral malignant lesions. Diagnostic accuracies obtained in this study highlight the potential use of this method for routine clinical practice.

6.
BMC Immunol ; 12: 19, 2011 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-21385406

RESUMO

BACKGROUND: Autoantibodies against glutamate decarboxylase-65 (GAD65Abs) are thought to be a major immunological tool involved in pathogenic autoimmunity development in various diseases. GAD65Abs are a sensitive and specific marker for type 1 diabetes (T1D). These autoantibodies can also be found in 6-10% of patients classified with type 2 diabetes (T2D), as well as in 1-2% of the healthy population. The latter individuals are at low risk of developing T1D because the prevalence rate of GAD65Abs is only about 0.3%. It has, therefore, been suggested that the antibody binding to GAD65 in these three different GAD65Ab-positive phenotypes differ with respect to epitope specificity. The specificity of reactive oxygen species modified GAD65 (ROS-GAD65) is already well established in the T1D. However, its association in secondary complications of T1D has not yet been ascertained. Hence this study focuses on identification of autoantibodies against ROS-GAD65 (ROS-GAD65Abs) and quantitative assays in T1D associated complications. RESULTS: From the cohort of samples, serum autoantibodies from T1D retinopathic and nephropathic patients showed high recognition of ROS-GAD65 as compared to native GAD65 (N-GAD65). Uncomplicated T1D subjects also exhibited reactivity towards ROS-GAD65. However, this was found to be less as compared to the binding recorded from complicated subjects. These results were further proven by competitive ELISA estimations. The apparent association constants (AAC) indicate greater affinity of IgG from retinopathic T1D patients (1.90 x 10⁻6 M) followed by nephropathic (1.81 x 10⁻6 M) and uncomplicated (3.11 x 10⁻7 M) T1D patients for ROS-GAD65 compared to N-GAD65. CONCLUSION: Increased oxidative stress and blood glucose levels with extended duration of disease in complicated T1D could be responsible for the gradual formation and/or exposing cryptic epitopes on GAD65 that induce increased production of ROS-GAD65Abs. Hence regulation of ROS-GAD65Abs could offer novel tools for analysing and possibly treating T1D complications.


Assuntos
Autoanticorpos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Glutamato Descarboxilase/imunologia , Espécies Reativas de Oxigênio/imunologia , Especificidade de Anticorpos/imunologia , Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/complicações , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/imunologia , Retinopatia Diabética/etiologia , Retinopatia Diabética/imunologia , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Humanos , Projetos Piloto
7.
J Biomed Opt ; 11(1): 014018, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16526895

RESUMO

A low-cost, fast, and noninvasive method for early diagnosis of malignant lesions of oral mucosa based on diffuse reflectance spectral signatures is presented. In this technique, output of a tungsten halogen lamp is guided to the tissue through the central fiber of a reflection probe whose surrounding six fibers collects tissue reflectance. Ex vivo diffuse reflectance spectra in the 400 to 600-nm region is measured from surgically removed oral cavity lesions using a miniature fiber optic spectrometer connected to a computer. Reflectance spectral intensity is higher in malignant tissues and shows dips at 542 and 577 nm owing to absorption from oxygenated hemoglobin (HbO2). Measurements carried out, within an hour of surgical excision, on malignant lesion and adjoining uninvolved mucosa show that these absorption features are more prominent in neoplastic tissues owing to increased microvasculature and blood content. It is observed that reflectance intensity ratio of hemoglobin bands, R540/R575, from malignant sites are always lower than that from normal sites and vary according to the histological grade of malignancy. The diffuse reflectance intensity ratio R540/R575 of the hemoglobin bands appears to be a useful tool to discriminate between malignant lesions and normal mucosa of the oral cavity in a clinical setting.


Assuntos
Biomarcadores Tumorais/análise , Diagnóstico por Computador/métodos , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/metabolismo , Proteínas de Neoplasias/análise , Oxiemoglobinas/análise , Fotometria/métodos , Análise Espectral/métodos , Humanos , Neoplasias Bucais/classificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Anesth Analg ; 99(5): 1453-1460, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15502048

RESUMO

Chronic pain after thoracotomy is common, although its basis and therapy have not been well characterized. In this study we characterize the allodynic responses (mechanical and cold) as well as the histopathologic changes after thoracotomy and rib retraction in rats. The antinociceptive effect of systemic and intrathecal analgesics was also evaluated. Male Sprague-Dawley rats were anesthetized and the right 4th and 5th ribs surgically exposed. The pleura was opened between the ribs and a retractor placed under both ribs and opened 8 mm. Retraction was maintained for 5, 30, or 60 min. Control animals had pleural incision only. Beginning Day 2 postsurgery, animals were tested for mechanical allodynia using calibrated von Frey filaments and cold allodynia using acetone applied to the incision site. Two weeks after surgery, animals were tested for reduction of allodynia with intraperitoneal and intrathecal injections of analgesics. Intercostal nerve histology was examined at 14 days postsurgery. Allodynia developed in 50% of the animals with 60 min retraction but in only 11% and 10% of animals when the retraction time was 5 and 30 min, respectively, and in none of the control animals. Allodynic animals showed extensive axon loss in the intercostal nerves of the retracted ribs. Allodynia appeared by Day 10 in the rib-retraction model and lasted at least 40 days. Systemic morphine sulfate (50% effective dose [ED(50)], 1.06 mg/kg) and gabapentin (ED(50), 24.2 mg/kg), as well as intrathecal morphine (ED(50), 1.19 nmol), gabapentin (ED(50), 13.8 nmol), clonidine (ED(50), 72.7 nmol), and neostigmine (ED(50), 0.54 nmol) reduced allodynia. Rib-retraction in rats for 60 min produces allodynia that lasts more than 1 mo, and this allodynia is reduced by morphine, gabapentin, clonidine, and neostigmine. This new model may be useful for quantifying the efficacy of techniques to reduce the frequency and severity of long-term postthoracotomy pain.


Assuntos
Dor Pós-Operatória/fisiopatologia , Toracotomia , Analgésicos/uso terapêutico , Animais , Doença Crônica , Temperatura Baixa , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Masculino , Medição da Dor , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/patologia , Nervos Periféricos/patologia , Estimulação Física , Ratos , Ratos Sprague-Dawley , Costelas/patologia , Costelas/cirurgia , Fixação de Tecidos , Aumento de Peso/fisiologia
9.
Appl Opt ; 22(22): 3612, 1983 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18200241

RESUMO

Nitrogen laser emission spectra was analyzed using a 0.5-m Jarrell-Ash monochromator. In addition to the (0,0) 337.1-nm band, the laser spectra were found to contain (0,1) 357.69-nm, (2,4) 371.05-nm, (1,0) 315.93-nm, (0,2) 380.49-nm, (0,3) 405.94-nm, (1,3) 375.54-nm, (1,4) 399.84-nm, and (1,2) 353.67-nm bands belonging to the second positive system of the N2 molecule. A new transition from one of the mixed vibrational levels of C and C' states of the N2 molecule was observed in the laser spectra at 331.83 nm with a relative intensity of approximately 29%. Two bands, at 340.85 and 303.49 nm, belonging to the beta system of the NO molecule were also observed. The intensity variation of the prominent bands observed was studied with respect to change in operating pressure and voltage for deriving the optimum conditions for emission at these wavelengths. Variations in the intensity of the bands were also studied with change in distance between the laser head and the monochromator; it was observed that an amplification effect had taken place at 331.83 and 340.85 nm, in addition to the (0,0) 337.1-nm band, in the nitrogen laser discharge.

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