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1.
Opt Express ; 24(2): 1708-22, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26832550

RESUMO

A new model is proposed for predicting the apparent dot area of simulated halftone prints on coated paper surface without requiring printing. It is based on Hotelling's multivariate T(2) statistic which is shown to provide a measure of lateral light scattering. The T(2) statistic is computed from colorimetric coordinates obtained from of a knife shadow image response on the paper surface. The proposed method offers superior prediction of halftone dot area compared to current light scattering models. A method for characterising peaks on the coated paper surface is introduced in this work. The effect of the paper coating layer thickness and the surface peak height on lateral light scattering and printed dot size are shown.

2.
Neoreviews ; 24(11): e720-e732, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37907403

RESUMO

Congenital diaphragmatic hernia (CDH) results in abdominal contents entering the thoracic cavity, affecting both cardiac and pulmonary development. Maldevelopment of the pulmonary vasculature occurs within both the ipsilateral lung and the contralateral lung. The resultant bilateral pulmonary hypoplasia and associated pulmonary hypertension are important components of the pathophysiology of this disease that affect outcomes. Despite prenatal referral to specialized high-volume centers, advanced ventilation strategies, pulmonary hypertension management, and the option of extracorporeal membrane oxygenation, overall CDH mortality remains between 25% and 30%. With increasing recognition that cardiac dysfunction plays a large role in morbidity and mortality in patients with CDH, it becomes imperative to understand the different clinical phenotypes, thus allowing for individual patient-directed therapies. Further research into therapeutic interventions that address the cardiopulmonary interactions in patients with CDH may lead to improved morbidity and mortality outcomes.


Assuntos
Hérnias Diafragmáticas Congênitas , Hipertensão Pulmonar , Gravidez , Feminino , Humanos , Hérnias Diafragmáticas Congênitas/terapia , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/terapia , Pulmão/anormalidades
3.
Chem Res Toxicol ; 22(3): 446-59, 2009 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-19222241

RESUMO

In the present study, we have investigated the effect of the aqueous extract of cigarette smoke (AECS) on tubulin-microtubule, a major cytoskeleton protein that maintains cellular morphology and participates in cell division. We found that treatment of AECS results in the loss of both structural and functional properties of tubulin-microtubule. Disruption of the microtubule network was observed in AECS-treated human lung epithelial (A549) cells and noncarcinoma human lung alveolar epithelium (L132) cells, in a dose and time-dependent manner. Tubulin-microtubule mediated important cellular properties, such as proliferation, migration, and maintenance of the cellular morphology, were affected by AECS in A549 cells. The aqueous extract of cigarette smoke (AECS) was also found to interfere the microtubule dynamics inside the cell and induce tubulin degradation. The structure of microtubules was also disrupted by AECS in the presence of protease inhibitors accompanied by a change of morphology of cells and loss of cell viability. In vitro, the functional properties of tubulin, such as the ability of polymerization, was inhibited by AECS in a dose and time-dependent manner, and it was accompanied by the loss of reactive cysteine residues, destabilization of the secondary structure, and quenching of intrinsic tryptophan fluorescence. Carbonyl content of tubulin was increased after treatment with AECS, indicating that one of the pathways of tubulin damage is protein oxidation. The damage of tubulin by AECS thus may be correlated with the pathogenesis of cigarette smoke induced disorders, which result in cellular apoptosis and tissue damage.


Assuntos
Células Epiteliais/efeitos dos fármacos , Pulmão/citologia , Microtúbulos/efeitos dos fármacos , Fumar/efeitos adversos , Tubulina (Proteína)/metabolismo , Linhagem Celular Tumoral , Células Epiteliais/citologia , Células Epiteliais/ultraestrutura , Humanos , Microtúbulos/ultraestrutura
4.
Steroids ; 139: 18-27, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30217788

RESUMO

Ichnocarpus frutescens, a climber plant, is distributed all over India. As its different parts are used as anti-inflammatory agent, so we re-investigated the roots to isolate compounds and evaluate its biological efficacy. Also, in-silico molecular docking was carried out to elucidate the structure activity relationship (SAR) of isolated compounds toward identifies the drug target enzyme with validation, which was further supported by anti-inflammatory in-vitro and in-vivo experimental models. The compounds have been undertaken mainly to investigate the anti-inflammatory and analgesic efficacy along with molecular docking investigation followed by anti-proteinase, anti-denaturation and cyclooxygenase (COX) inhibition studies. Inflammatory cytokines like TNF-α and IL-6 were assayed from lipopolysaccharides (LPS) and Concavallin (CON A) stimulated human PBMC derived macrophages by Enyme linked immune sorbent assay (ELISA) method. The purity index of the lead compound was determined by HPLC. The compounds were illustrated as 2-hydroxy tricosanoic acid (1), stigmasterol glucoside (2), stigmasterol (3), ß-sitosterol (4) and ß-sitosterol glucoside (5). The test molecules showed significant anti-denaturation, anti-proteinase and analgesic effect validated with docking study. Compounds exhibited anti-inflammatory and pain killing action due to dexamethasone like phytosterol property. Promising anti-denaturation and anti-proteinase activity offered by the compound 5, may hold its promise to fight against arthritis by rejuvenating the osteoblast cells and destroying the bone-resorpting complex of hydrated protein, bone minerals by secreting the acid and an enzyme collagenase along with pain management. The lead bioactive compound i.e. ß-sitosterol glucoside (compound 5) demonstrated considerable anti-inflammatory activity showing more than 90% protection against the inflammatory cytokines at 50 µM dose. The anti-denaturation and COX-2 inhibition shown by the compound 5 was also noteworthy with the significant IC50 (ranging from 0.25 to 2.56 µM) that also supporting its future promise for developing as anti-inflammatory agent. Since the most bio-active compound (5) elicit promising acute anti-inflammatory action and peripheral anti-nociceptive pain killing action with a significant ED50 dose of 3.95 & 2.84 mg/kg i.p. respectively in the in-vivo animal model. It could suggest its potentiality as a good in-vivo bio available agent to be an emerging anti-inflammatory drug regimen scaffold in the future. It also establishes significant in-vitro and in-vivo result co-relation. Therefore, the compound 5 could be believed as a potent lead for designing anti-inflammatory, anti-arthritic drug or pain killer without showing any untoward effect.


Assuntos
Apocynaceae/química , Inflamação/tratamento farmacológico , Dor Nociceptiva/tratamento farmacológico , Esteroides/administração & dosagem , Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/isolamento & purificação , Glucosídeos/química , Glucosídeos/isolamento & purificação , Humanos , Inflamação/patologia , Interleucina-6/genética , Leucócitos Mononucleares/efeitos dos fármacos , Lipopolissacarídeos/química , Macrófagos/efeitos dos fármacos , Simulação de Acoplamento Molecular , Dor Nociceptiva/patologia , Percepção da Dor/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Sitosteroides/química , Sitosteroides/isolamento & purificação , Esteroides/química , Esteroides/isolamento & purificação , Estigmasterol/análogos & derivados , Estigmasterol/química , Estigmasterol/isolamento & purificação , Fator de Necrose Tumoral alfa/genética
5.
BMJ Simul Technol Enhanc Learn ; 2(4): 103-107, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-35514867

RESUMO

Introduction: Learning of simulation-based crisis management skills involves technologically advanced manikins and use of automated scenarios. Progressions in preprogrammed scenarios require finite task completion such as successful airway intubations for achieving optimal learning outcomes aligned to curricular goals. The study was set to explore the existing variability among various simulation manikins in use at our institute for undergraduate medical education. Methods: 56 final-year undergraduate students, who had received prior training in airway management skills, performed intubations on each of the 5 different manikins (56×5=280 intubations). The manikins used were the Human Patient Simulator (HPS), iStan & Emergency Care Simulator (ECS) from CAE Healthcare and Mega Code Kelly (MCK) and Airway Trainer (AWTR) from Laerdal. The students' performances were compared for success rates, ease of intubation, grade of laryngeal visualisation and presence of tooth injury on the manikins, Data from the intubations were cross-tabulated and evaluated by general estimating equation analysis using the Poisson model. Results: iStan had the higher rates of failure to intubate (64.3%). iStan (62.5%) and HPS (57.1%) had statistically significant teeth injury (p<0.0001) compared to other manikins. HPS and AWTR had the least difficult grades of laryngeal visualisation (Cormack Lehane grades 1 and 2), while the most difficult grade of visualisation (Cormack Lehane grades 3 and 4) was reported in ECS (44.6%). Conclusions: Each of the high-technology manikins used in automated scenarios for crisis management teaching and learning has heterogeneity in airway features. Since frequent airway management is a critical component of simulation scenarios, this can affect student performance when these manikins are used for formative and summative high-stakes assessments.

6.
Clin Biochem ; 38(7): 678-80, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16009145

RESUMO

OBJECTIVES: Evaluation of immunological alterations in the blood of human lindane poisoning cases. DESIGN AND METHODS: Serum IgG, IgM, IgA, IgE, IL-2, IL-4, TNF-alpha, and IFN-gamma levels were measured using immunoassay in 20 human cases of lindane poisoning. The presence of lindane in blood was confirmed by HPLC. RESULTS: Serum IL-2, IL-4, and TNF-alpha levels were significantly raised with decrease in IFN-gamma levels in the lindane-exposed cases. Immunoglobulin levels were not altered. CONCLUSIONS: The results suggest that lindane exposure at chronically high levels affects cytokine levels in humans and indicates the severity of immunotoxicity.


Assuntos
Formação de Anticorpos/efeitos dos fármacos , Hexaclorocicloexano/intoxicação , Imunidade/efeitos dos fármacos , Imunoglobulinas/sangue , Interferon gama/sangue , Interleucina-2/sangue , Interleucina-4/sangue , Intoxicação/imunologia , Fator de Necrose Tumoral alfa/análise
7.
Saudi J Anaesth ; 8(4): 493-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25422607

RESUMO

OBJECTIVE: To ascertain the awareness regarding global warming and the anesthesia practices contributing to it in the city of Delhi. MATERIALS AND METHODS: A questionnaire was circulated amongst the qualified anesthesiologists (consultants and senior residents) in the city of Delhi. The initial contact was made through e-mail and the questionnaire was required to be filled and returned electronically. The questionnaire was also made available online at http://sites.google.com/site/surveydelhi. After 1 month, the forms were distributed physically. Assuming that at least 50% of the approximately 1200 practising anesthesiologists would be able to recognize the greenhouse gases correctly, the target number of responses was 150 with 99% confidence limit. RESULTS: Of the 831 anesthesiologists contacted, only 184 responded. Ninety-eight percent were aware of the greenhouse effect, but only 15.8% (29) could correctly identify all the greenhouse gases. However, 47.28% (87) could identify nitrous oxide and inhalational agents as a cause of greenhouse effect. Ninety percent of the respondents use circle system and 87% use low flows frequently. Ninety-three percent (171) of respondents routinely use nitrous oxide, and 32.1% (59) would, however, not use air even if made available. Seventy-nine percent (145) advocated total intravenous anesthesia as an alternative to reduce the menace. CONCLUSION: Only 22% were motivated enough to respond to the survey. More than half of these anesthesiologists were not aware about the anesthetic agents contributing to the greenhouse effect. However, their clinical practices inadvertently do not add to the environmental pollution.

8.
PLoS One ; 8(7): e68224, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23874548

RESUMO

Smokeless tobacco usage is a growing public health problem worldwide. The molecular mechanism(s) underlying smokeless tobacco associated tissue damage remain largely unidentified. In the present study we have tried to explore the effects of aqueous extract of smokeless tobacco (STE) on tubulin-microtubule, the major cytoskeleton protein that maintains cells morphology and participates in cell division. Exposure to STE resulted in dose-dependent cytotoxicity in a variety of mammalian transformed cell lines such as human lung epithelial cells A549, human liver epithelial cells HepG2, and mouse squamous epithelial cells SCC7, [corrected] as well as non-tumorogenic human peripheral blood mononuclear cells PBMC. Cellular morphology of STE-treated cells was altered and the associated disruption of microtubule network indicates that STE targets tubulin-microtubule system in both cell lines. Furthermore it was also observed that STE-treatment resulted in the selective degradation of cellular tubulin, whereas actin remains unaltered. In vitro, polymerization of purified tubulin was inhibited by STE with the IC50 value∼150 µg/ml and this is associated with the loss of reactive cysteine residues of tubulin. Application of thiol-based antioxidant N-acetyl cysteine (NAC) significantly abrogates STE-mediated microtubule damage and associated cytotoxicity in both A549 and HepG2 cells. These results suggest that microtubule damage is one of the key mechanisms of STE-induced cytotoxity in mammalian cells.


Assuntos
Microtúbulos/efeitos dos fármacos , Tabaco sem Fumaça/toxicidade , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cisteína/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Hep G2 , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Microtúbulos/metabolismo , Extratos Vegetais/toxicidade , Polimerização/efeitos dos fármacos , Tubulina (Proteína)/metabolismo
9.
Indian J Crit Care Med ; 15(3): 157-63, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22013307

RESUMO

INTRODUCTION: There is paucity of data from India regarding the etiology, prognostic indicators, morbidity, and mortality patterns of perforation peritonitis. The objective of our study was to evaluate the predictors of mortality, preoperatively, for risk stratification of the patients and institution of an early goal-directed therapy. MATERIALS AND METHODS: Eighty-four consecutive patients presenting with perforation peritonitis, in the age group of 14-70 years scheduled for emergency laparotomy were studied prospectively. The parameters studied were age and sex of the patients, associated co-morbidities, duration of symptoms, delay in initiating surgical intervention, and preoperative biochemical parameters such as hemoglobin, random blood sugar, blood urea, serum creatinine, pH, base excess, and serum lactate levels. In-hospital mortality was taken as the outcome. RESULTS: We encountered a mortality of 17.8% in our study. Multiple linear (enter) regression identified the age, duration of symptoms, preoperative blood sugar levels, blood urea, serum creatinine levels, Mannheim Peritonitis Index, and the delay in instituting surgical intervention as independent predictors of mortality. Hyperlactatemia, acidosis and base excess were not found to be associated with mortality. CONCLUSION: Routine biochemical investigations, delay in presentation, and surgical intervention are good predictors of mortality. Recognizing such patients early may help the anesthesiologists in risk stratification and in providing an early goal-directed therapy.

10.
J Agric Food Chem ; 59(5): 2040-8, 2011 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-21323312

RESUMO

Here we studied the antiproliferative activity of theaflavins in cervical carcinoma HeLa cells by investigating their effects on cellular microtubules and purified goat brain tubulin. Theaflavins inhibited proliferation of HeLa cells with IC(50) value of 110 ± 2.1 µg/mL (p = < 0.01), caused cell cycle arrest at G(2)/M phase and induced apoptosis with alteration of expression of pro- and antiapoptotic proteins. Along with these antiproliferative activities, theaflavins act as microtubule depolymerizers. Theaflavins disrupted the microtubule network accompanied by alteration of cellular morphology and also decreased the polymeric tubulin mass of the cells. The polymerization of cold treated depolymerized microtubules in HeLa cells was prevented in the presence of theaflavins. In vitro polymerization of purified tubulin into microtubules was also inhibited by theaflavins with an IC(50) value of 78 ± 2.43 µg/mL (P < 0.01). Thus, disruption of cellular microtubule network of HeLa cells through microtubule depolymerization may be one of the possible mechanisms of antiproliferative activity of theaflavins.


Assuntos
Apoptose/efeitos dos fármacos , Biflavonoides/farmacologia , Catequina/farmacologia , Divisão Celular/efeitos dos fármacos , Microtúbulos/química , Tubulina (Proteína)/metabolismo , Imunofluorescência , Fase G2/efeitos dos fármacos , Células HeLa , Humanos , Microtúbulos/efeitos dos fármacos , Polimerização/efeitos dos fármacos , Tubulina (Proteína)/química , Moduladores de Tubulina/farmacologia
11.
Food Chem Toxicol ; 48(10): 2872-80, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20647029

RESUMO

Ginger has a long history of use as traditional medicine for varied human disease. Our present study has shown that the aqueous extract of ginger (GAE) interacts directly with cellular microtubules and disrupts its structure and induces apoptosis of cancer cells as well. The IC(50) values of GAE, as determined from cell viability experiment on human non-small lung epithelium cancer (A549) cells and human cervical epithelial carcinoma (HeLa), were 239.4+7.4 and 253.4+8.9 µg/ml, respectively. It has been found that the apoptosis of A549 cells by GAE is mediated by up regulation of tumor suppressor gene p53 and alteration of the normal Bax/Bcl-2 ratio followed by down regulation of cellular pro-caspase3. The morphological change of cells upon GAE treatment has also been demonstrated. Both the structural and functional properties of tubulin and microtubule were lost, as confirmed by both ex vivo and invitro experiments. The major component of GAE is poly-phenols (around 2.5%), which consist of ∼ 80% flavones and flavonols. Poly-phenolic compounds are well known to have anti-mitotic properties, and may be further screened for the development of a potential anti-cancer agent.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Microtúbulos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Zingiber officinale/química , Apoptose/efeitos dos fármacos , Western Blotting , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA de Neoplasias/biossíntese , Flavonas/química , Flavonas/farmacologia , Flavonóis/química , Flavonóis/farmacologia , Citometria de Fluxo , Células HeLa , Humanos , Potenciais da Membrana/efeitos dos fármacos , Microtúbulos/patologia , Microtúbulos/ultraestrutura , Mitocôndrias/efeitos dos fármacos , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Tubulina (Proteína)/efeitos dos fármacos , Tubulina (Proteína)/metabolismo
12.
Chem Pharm Bull (Tokyo) ; 54(5): 679-81, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16651765

RESUMO

A new C-alkylglucoside, diospyrodin [beta-1C-(1'S*,2'R*,3'R*,4'S*-1',2',3',4',5'-pentahydroxypentyl)-glucopyranoside] (1) has been isolated as its nonaacetate from the leaves and stems of Diospyros nigra. Its structure was elucidated on the basis of chemical and spectral properties and a single crystal X-ray analysis. It showed antimicrobial activity against Gram-positive and Gram-negative bacteria.


Assuntos
Antibacterianos/química , Diospyros/química , Glucosídeos/química , Acetilação , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Glucosídeos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Relação Estrutura-Atividade , Difração de Raios X
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