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1.
Expert Rev Clin Pharmacol ; : 1-15, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39230196

RESUMO

INTRODUCTION: Chronic spontaneous urticaria (CSU) is characterized by urticaria persisting for more than 6 weeks. Antihistamines, notably sgAH (second generation antihistamines) are the first line of treatment for CSU. AREAS COVERED: This consensus aimed to review the existing research on receptor occupancy of antihistamines, including levocetirizine, and translate its implications in the treatment of CSU. The consensus deliberations were under the banner of the Antihistamine Receptor Occupancy Group (AROG) from India, an expert panel of 12 dermatologists with a mix of institutional and practitioner backgrounds. This group analyzed the existing translational research on the receptor occupancy of levocetirizine to establish the clinical efficacy and safety of levocetirizine in the treatment of CSU using the grading of recommendations assessment, development, and evaluation (GRADE) method vis-a-vis the varied SGAH. EXPERT OPINION: SGAH constitute the first step in the therapeutic ladder for managing CSU. Levocetirizine has high bioavailability, high affinity and occupancy of the H1 receptor, rapid onset of action, limited distribution and minimal hepatic metabolism. It exhibits significant anti-inflammatory effects at clinically relevant concentrations. The marked receptor occupancy translates to enhanced efficacy as compared to similarly dosed SGAH with the lower cost making it an appropriate drug for chronic use. Receptor occupancy should be the basis of intra-class head-to-head trials in CSU.

2.
J Biosoc Sci ; 56(2): 314-337, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37577970

RESUMO

Adolescence is a unique transitional stage of physical and psychological development. As preferences and behavioural choices adopted in adolescence influence lifelong physical activity habits and health outcomes in adulthood, rural transformation in low- and middle-income countries has the potential to significantly change traditional roles and shape the next generation. By using a mixed-method approach that integrates energy expenditure estimates from accelerometer devices with 24-hour recall time-use data from adolescent boys and girls and qualitative interviews with adolescents and their caregivers, this study sheds light on the patterns of quantity and quality of physical activity of 395 adolescents in Khammam and Mahbubnagar districts of rural Telangana, India. The study shows that energy expenditure and time use are highest for educational-related activities followed by leisure in both adolescent boys and girls. However, notwithstanding the process of rural transformation and the educational infrastructure and economic opportunities provided to adolescent boys and girls, social and cultural norms allow boys, especially in late adolescence to spend more time and energy in activities outside the home such as pursuing economic work, sports and socialising, while girls spend more time and energy at home doing domestic work. The quantitative and qualitative exploration of physical activity and time use among adolescents, as expounded in this study cutting across age groups and gender, highlights the need for changes in gendered norms and renewed government strategies and investments in that direction.


Assuntos
Identidade de Gênero , Esportes , Masculino , Feminino , Humanos , Adolescente , Escolaridade , População Rural , Exercício Físico
3.
Sci Data ; 7(1): 71, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127539

RESUMO

With more than 820 million undernourished people living in rural areas of low- and middle-income countries (LMICs), ending hunger and ensuring access to food by all is a global priority. In the past few decades, the adoption of technological innovations in the agricultural sector and related crop yield improvements have not led to expected improvements in the nutritional status of rural households in many LMICs. The increased energy expenditure associated with the adoption of productivity-enhancing innovations may provide an important explanation of the disconnect between agricultural productivity enhancements and improved nutritional outcomes. We develop a methodology for generating reliable livelihood energy/calorie expenditure profiles for rural agricultural households using research-grade accelerometer devices. We integrate the data on physical activity and energy expenditure in rural households with data on time-use and food intakes to generate a data set that provides a unique window into rural livelihoods. This can be a valuable resource to analyse agriculture-nutrition impact pathways and improve the welfare of rural and agricultural households.


Assuntos
Agricultura , Ingestão de Alimentos , Exercício Físico , População Rural , Acelerometria , Eficiência , Metabolismo Energético , Características da Família , Gana , Humanos , Índia , Nepal , Estado Nutricional
4.
Econ Hum Biol ; 37: 100846, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31927034

RESUMO

Low and middle-income countries in Asia and Africa have been witnessing a process of rural transformation, characterised by rising agricultural productivity, commercialisation of agriculture, improved infrastructure and access to services, over several decades. However, there is little empirical evidence on how this transformation process has affected the patterns and intensity of physical activity and time use in rural livelihoods. The lack of empirical evidence can be attributed to the constraints in accurate measurement of physical activity and energy expenditure in the context of free-living populations. Using wearable accelerometry devices, we develop robust energy expenditure profiles for men and women in rural households for two case studies in India and Ghana. An innovative feature of this study is the integration of data on energy expenditure (derived from accelerometers) with data on time-use, which has hitherto not been feasible in observational studies of rural populations. Using the data on physical activity, energy expenditure and time use from the case studies, we examine the impact of drudgery reduction- the substitution of less intense for more intense activities - on energy requirements for men and women in rural households. Our results show that drudgery reduction can have large effects on human energy (calorie) requirements, with an hour of drudgery reduction reducing energy requirements by 11-22 % for men and 13-17 % for women in Ghana and India. There are significant gender differences in energy expenditure patterns and drudgery reduction effects vary by socio-demographic characteristics and endowments of households. Our results suggest that drudgery reduction can offer rural households an important route to improved nutritional status. At the same time, drudgery reduction can lead to increased incidence of overweight and obesity for some segments of the population. The design of development interventions needs to explicitly consider the effects on nutrition and well-being through the energy expenditure dimension.


Assuntos
Agricultura/estatística & dados numéricos , Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Fazendeiros , População Rural , Adulto , Países em Desenvolvimento , Ingestão de Energia , Feminino , Gana , Humanos , Índia , Masculino , Estado Nutricional , Fatores Sexuais , Fatores Socioeconômicos
5.
PLoS One ; 11(9): e0162668, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27649080

RESUMO

In many developing countries, high levels of child undernutrition persist alongside rapid economic growth. There is considerable interest in the study of countries that have made rapid progress in child nutrition to uncover the driving forces behind these improvements. Cambodia is often cited as a success case having reduced the incidence of child stunting from 51% to 34% over the period 2000 to 2014. To what extent is this success driven by improvements in the underlying determinants of nutrition, such as wealth and education, ("covariate effects") and to what extent by changes in the strengths of association between these determinants and nutrition outcomes ("coefficient effects")? Using determinants derived from the widely-applied UNICEF framework for the analysis of child nutrition and data from four Demographic and Health Surveys datasets, we apply quantile regression based decomposition methods to quantify the covariate and coefficient effect contributions to this improvement in child nutrition. The method used in the study allows the covariate and coefficient effects to vary across the entire distribution of child nutrition outcomes. There are important differences in the drivers of improvements in child nutrition between severely stunted and moderately stunted children and between rural and urban areas. The translation of improvements in household endowments, characteristics and practices into improvements in child nutrition (the coefficient effects) may be influenced by macroeconomic shocks or other events such as natural calamities or civil disturbance and may vary substantially over different time periods. Our analysis also highlights the need to explicitly examine the contribution of targeted child health and nutrition interventions to improvements in child nutrition in developing countries.


Assuntos
Transtornos da Nutrição Infantil/prevenção & controle , Fenômenos Fisiológicos da Nutrição Infantil , Transtornos do Crescimento/prevenção & controle , Inquéritos Epidemiológicos/métodos , Análise de Variância , Camboja/epidemiologia , Criança , Transtornos da Nutrição Infantil/epidemiologia , Pré-Escolar , Comorbidade , Desenvolvimento Econômico/estatística & dados numéricos , Feminino , Transtornos do Crescimento/epidemiologia , Inquéritos Epidemiológicos/estatística & dados numéricos , Inquéritos Epidemiológicos/tendências , Humanos , Incidência , Lactente , Masculino , Estado Nutricional , Saúde da População Rural/estatística & dados numéricos , Fatores Socioeconômicos , Saúde da População Urbana/estatística & dados numéricos
6.
Saudi J Anaesth ; 10(3): 359-61, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27375400

RESUMO

The main goals of neuroanesthesia are the maintenance of adequate cerebral perfusion pressure, avoidance of hypercarbia, hypoxemia, and to provide better brain relaxation. Providing anesthesia for a patient with bronchiectasis needing lung isolation for craniotomy can be challenging. A 56-year-old male patient, case of right lung bronchiectasis with a right cerebello pontine angle tumor underwent excision in the left lateral position. Since he had severe bronchiectasis of the right lung, we had isolated the right lung using right-sided double lumen tube to avoid spillage. Intraoperative split lung test was performed to assess the right lung contribution on carbon dioxide (CO2) elimination and found that there was a significant contribution from the right lung. Hence, both lungs were ventilated to control CO2. The importance of lung isolation to prevent spillage and avoidance of one lung ventilation to control the arterial CO2 are highlighted in this case report. By providing a balanced anesthetic keeping both, the neurosurgical and thoracic concerns are important for better postoperative outcome.

7.
BMJ Open ; 3(6)2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23801712

RESUMO

OBJECTIVE: To systematically review the available evidence on whether national or international agricultural policies that directly affect the price of food influence the prevalence rates of undernutrition or nutrition-related chronic disease in children and adults. DESIGN: Systematic review. SETTING: Global. SEARCH STRATEGY: We systematically searched five databases for published literature (MEDLINE, EconLit, Agricola, AgEcon Search, Scopus) and systematically browsed other databases and relevant organisational websites for unpublished literature. Reference lists of included publications were hand-searched for additional relevant studies. We included studies that evaluated or simulated the effects of national or international food-price-related agricultural policies on nutrition outcomes reporting data collected after 1990 and published in English. PRIMARY AND SECONDARY OUTCOMES: Prevalence rates of undernutrition (measured with anthropometry or clinical deficiencies) and overnutrition (obesity and nutrition-related chronic diseases including cancer, heart disease and diabetes). RESULTS: We identified a total of four relevant reports; two ex post evaluations and two ex ante simulations. A study from India reported on the undernutrition rates in children, and the other three studies from Egypt, the Netherlands and the USA reported on the nutrition-related chronic disease outcomes in adults. Two of the studies assessed the impact of policies that subsidised the price of agricultural outputs and two focused on public food distribution policies. The limited evidence base provided some support for the notion that agricultural policies that change the prices of foods at a national level can have an effect on population-level nutrition and health outcomes. CONCLUSIONS: A systematic review of the available literature suggests that there is a paucity of robust direct evidence on the impact of agricultural price policies on nutrition and health.

8.
Econ Hum Biol ; 11(4): 574-91, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23665354

RESUMO

The facilitation of healthier dietary choices by consumers is a key element of government strategies to combat the rising incidence of obesity in developed and developing countries. Public health campaigns to promote healthier eating often target compliance with recommended dietary guidelines for consumption of individual nutrients such as fats and added sugars. This paper examines the association between improved compliance with dietary guidelines for individual nutrients and excess calorie intake, the most proximate determinant of obesity risk. We apply quantile regressions and counterfactual decompositions to cross-sectional data from the National Diet and Nutrition Survey (2000-01) to assess how excess calorie consumption patterns in the UK are likely to change with improved compliance with dietary guidelines. We find that the effects of compliance vary significantly across different quantiles of calorie consumption. Our results show that compliance with dietary guidelines for individual nutrients, even if successfully achieved, is likely to be associated with only modest shifts in excess calorie consumption patterns. Consequently, public health campaigns that target compliance with dietary guidelines for specific nutrients in isolation are unlikely to have a significant effect on the obesity risk faced by the population.


Assuntos
Dieta , Ingestão de Energia , Fidelidade a Diretrizes , Obesidade/prevenção & controle , Adulto , Estudos Transversais , Feminino , Humanos , Estilo de Vida , Masculino , Obesidade/epidemiologia , Reino Unido/epidemiologia
9.
J Proteomics ; 79: 219-30, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-23313214

RESUMO

The endoplasmic reticulum (ER) and mitochondria communicate via contact sites known as mitochondria-associated ER membranes or MAM. The region has emerged as the primary area of Ca(2+) traffic between the two organelles, and as such, has been implicated in the regulation of protein folding, oxidative phosphorylation, and Ca(2+)-mediated apoptosis. In order to better understand biological processes and molecular functions at the MAM, we report a global mass spectrometry-based proteomic evaluation of the MAM obtained from mouse brain samples. Gel-assisted sample preparation in conjunction with our two-dimensional chromatography approach allowed for the identification of 1,212 high confidence proteins. Bioinformatic interrogation of this protein catalogue using Ingenuity Pathway Analysis revealed new potential connections between our list of MAM proteins and neurodegenerative diseases in addition to anticipated biological processes. Based on our results, we postulate that proteins of the MAM may play essential roles in dysfunctions responsible for several neurological disorders in addition to facilitating key cellular survival processes.


Assuntos
Retículo Endoplasmático/metabolismo , Membranas Intracelulares/metabolismo , Membranas Mitocondriais/metabolismo , Animais , Encéfalo/ultraestrutura , Fracionamento Celular , Masculino , Camundongos , Mitocôndrias Hepáticas/metabolismo , Doenças Neurodegenerativas/metabolismo , Proteômica
10.
Plant Cell Rep ; 30(4): 655-64, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21212958

RESUMO

Transgenic plants of tobacco (Nicotiana tabacum L) and European plum (Prunus domestica L) were produced by transforming with the apple class 1 KNOX genes (MdKN1 and MdKN2) or corn KNOX1 gene. Transgenic tobacco plants were regenerated in vitro from transformed leaf discs cultured in a medium lacking cytokinin. Ectopic expression of KNOX genes retarded shoot growth by suppressing elongation of internodes in transgenic tobacco plants. Expression of each of the three KNOX1 genes induced malformation and extensive lobbing in tobacco leaves. In situ regeneration of adventitious shoots was observed from leaves and roots of transgenic tobacco plants expressing each of the three KNOX genes. In vitro culture of leaf explants and internode sections excised from in vitro grown MdKN1 expressing tobacco shoots regenerated adventitious shoots on MS (Murashige and Skoog 1962) basal medium in the absence of exogenous cytokinin. Transgenic plum plants that expressed the MdKN2 or corn KNOX1 gene grew normally but MdKN1 caused a significant reduction in plant height, leaf shape and size and produced malformed curly leaves. A high frequency of adventitious shoot regeneration (96%) was observed in cultures of leaf explants excised from corn KNOX1-expressing transgenic plum shoots. In contrast to KNOX1-expressing tobacco, leaf and internode explants of corn KNOX1-expressing plum required synthetic cytokinin (thidiazuron) in the culture medium to induce adventitious shoot regeneration. The induction of high-frequency regeneration of adventitious shoots in vitro from leaves and stem internodal sections of plum through the ectopic expression of a KNOX1 gene is the first such report for a woody perennial fruit trees.


Assuntos
Nicotiana/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Prunus/crescimento & desenvolvimento , Proteínas de Homeodomínio/genética , Proteínas de Plantas/genética , Brotos de Planta/genética , Reação em Cadeia da Polimerase , Prunus/genética , Nicotiana/genética
11.
Eur J Med Chem ; 45(9): 3709-18, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20627471

RESUMO

A series of novel dibenzo[b,d]furan mono-carboxylic acid derivatives were synthesized, characterized and evaluated for their ability to inhibit Protein Tyrosine Phosphatase 1B (PTP1B) in vitro in order to use them as potential anti-diabetic agents. Structure-activity relationship study led to the identification of potent compound 5 E which inhibited PTP1B with IC(50) value of 82+/-0.43 nM. Compound 5 E was screened in vivo as drug candidate for anti-diabetic activity using rosiglitazone maleate as the standard. Compound 5 E showed significant reduction in body weight, fed-state whole blood glucose (WBG), fasting WBG, plasma glucose and plasma cholesterol levels and non-significant reduction in fasting plasma triglyceride levels in ob/ob mice.


Assuntos
Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/farmacologia , Furanos/química , Hipoglicemiantes/síntese química , Hipoglicemiantes/farmacologia , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Ácidos Carboxílicos/química , Domínio Catalítico , Colesterol/sangue , Descoberta de Drogas , Hipoglicemiantes/química , Concentração Inibidora 50 , Masculino , Camundongos , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 1/química , Especificidade por Substrato , Triglicerídeos/sangue
12.
J Proteome Res ; 9(4): 1746-53, 2010 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-20131867

RESUMO

The human cannabinoid 1 receptor (hCB1), a ubiquitous G protein-coupled receptor (GPCR), transmits cannabinergic signals that participate in diverse (patho)physiological processes. Pharmacotherapeutic hCB1 targeting is considered a tractable approach for treating such prevalent diseases as obesity, mood disorders, and drug addiction. The hydrophobic nature of the transmembrane helices of hCB1 presents a formidable difficulty to its direct structural analysis. Comprehensive experimental characterization of functional hCB1 by mass spectrometry (MS) is essential to the targeting of affinity probes that can be used to define directly hCB1 binding domains using a ligand-assisted experimental approach. Such information would greatly facilitate the rational design of hCB1-selective agonists/antagonists with therapeutic potential. We report the first high-coverage MS analysis of the primary sequence of the functional hCB1 receptor, one of the few such comprehensive MS-based analyses of any GPCR. Recombinant C-terminal hexa-histidine-tagged hCB1 (His6-hCB1) was expressed in cultured insect (Spodoptera frugiperda) cells, solubilized by a procedure devised to enhance receptor purity following metal-affinity chromatography, desalted by buffer exchange, and digested in solution with (chymo)trypsin. "Bottom-up" nanoLC-MS/MS of the (chymo)tryptic digests afforded a degree of overall hCB1 coverage (>94%) thus far reported for only two other GPCRs. This MS-compatible procedure devised for His6-hCB1 sample preparation, incorporating in-solution (chymo)trypsin digestion in the presence of a low concentration of CYMAL-5 detergent, may be applicable to the MS-based proteomic characterization of other GPCRs. This work should help enable future ligand-assisted structural characterization of hCB1 binding motifs at the amino-acid level using rationally designed and targeted covalent cannabinergic probes.


Assuntos
Fragmentos de Peptídeos/metabolismo , Proteômica/métodos , Receptor CB1 de Canabinoide/química , Proteínas Recombinantes de Fusão/metabolismo , Espectrometria de Massas em Tandem/métodos , Sequência de Aminoácidos , Western Blotting , Desenho de Fármacos , Histidina/genética , Humanos , Interações Hidrofóbicas e Hidrofílicas , Dados de Sequência Molecular , Oligopeptídeos/genética , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Transdução de Sinais
13.
Eur J Med Chem ; 44(8): 3147-57, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19349096

RESUMO

A series of novel isochroman mono-carboxylic acid derivatives were synthesized, characterized and evaluated for their ability to inhibit protein tyrosine phosphatase 1B (PTP1B) in vitro in order to use them as potential anti-diabetic agents. Analysis of structure-activity relationships led to the identification of potent compound 4n which inhibited PTP1B with IC(50) value of 51.63+/-0.91 nM. In general, high potency was associated with a dithiolane ring with a spacer of five carbons to the isochroman ring. Compound 4n has been selected for in vivo evaluation as drug candidate for anti-diabetic activity.


Assuntos
Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/farmacologia , Desenho de Fármacos , Hipoglicemiantes/síntese química , Hipoglicemiantes/farmacologia , Animais , Ácidos Carboxílicos/química , Hipoglicemiantes/química , Concentração Inibidora 50 , Masculino , Camundongos , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Estereoisomerismo , Relação Estrutura-Atividade
15.
Chem Biol ; 15(8): 854-62, 2008 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-18721756

RESUMO

The active site of recombinant hexa-histidine-tagged human monoacylglycerol lipase (hMGL) is characterized by mass spectrometry using the inhibitors 5-((biphenyl-4-yl)methyl)-N,N-dimethyl-2H-tetrazole-2-carboxamide (AM6701), and N-arachidonylmaleimide (NAM) as probes. Carbamylation of Ser(129) by AM6701 in the putative hMGL catalytic triad demonstrates this residue's essential role in catalysis. Partial NAM alkylation of hMGL cysteine residues 215 and/or 249 was sufficient to achieve approximately 80% enzyme inhibition. Although Cys(215) and/or Cys(249) mutations to alanine(s) did not affect hMGL hydrolytic activity as compared with nonmutated hMGL, the C215A displayed heightened NAM sensitivity, whereas the C249A evidenced reduced NAM sensitivity. These data conclusively demonstrate a sulfhydryl-based mechanism for NAM inhibition of hMGL in which Cys(249) is of paramount importance. Identification of amino acids critical to the catalytic activity and pharmacological modulation of hMGL informs the design of selective MGL inhibitors as potential drugs.


Assuntos
Domínio Catalítico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Monoacilglicerol Lipases/antagonistas & inibidores , Monoacilglicerol Lipases/química , Mutação , Amidas/química , Amidas/farmacologia , Sequência de Aminoácidos , Desenho de Fármacos , Humanos , Isomerismo , Ligantes , Maleimidas/química , Maleimidas/farmacologia , Espectrometria de Massas , Dados de Sequência Molecular , Monoacilglicerol Lipases/genética , Monoacilglicerol Lipases/metabolismo , Mutagênese Sítio-Dirigida
16.
J Proteome Res ; 7(5): 2158-64, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18452279

RESUMO

The serine hydrolase monoacylglycerol lipase (MGL) modulates endocannabinoid signaling in vivo by inactivating 2-arachidonoylglycerol (2-AG), the main endogenous agonist for central CB1 and peripheral CB2 cannabinoid receptors. To characterize this key endocannabinoid enzyme by mass spectrometry-based proteomics, we first overexpressed recombinant hexa-histidine-tagged human MGL (hMGL) in Escherichia coli and purified it in a single chromatographic step with high yield (approximately 30 mg/L). With 2-AG as substrate, hMGL displayed an apparent V max of 25 micromol/(microg min) and K m of 19.7 microM, an affinity for 2-AG similar to that of native rat-brain MGL (rMGL) (Km=33.6 microM). hMGL also demonstrated a comparable affinity (Km approximately 8-9 microM) for the novel fluorogenic substrate, arachidonoyl, 7-hydroxy-6-methoxy-4-methylcoumarin ester (AHMMCE), in a sensitive, high-throughput fluorometric MGL assay. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) unequivocably demonstrated the mass (34,126 Da) and purity of this hMGL preparation. After in-solution tryptic digestion, hMGL full proteomic characterization was carried out, which showed (1) an absence of intramolecular disulfide bridges in the functional, recombinant enzyme and (2) the post-translational removal of the enzyme's N-terminal methionine. Availability of sufficient quantities of pure, well-characterized hMGL will enable further molecular and structural profiling of this key endocannabinoid-system enzyme.


Assuntos
Monoacilglicerol Lipases/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sequência de Aminoácidos , Animais , Moduladores de Receptores de Canabinoides/química , Humanos , Dados de Sequência Molecular , Monoacilglicerol Lipases/genética , Monoacilglicerol Lipases/isolamento & purificação , Proteômica/métodos , Ratos
18.
J Biol Chem ; 282(13): 9713-9721, 2007 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-17264082

RESUMO

It is well accepted that high levels of high density lipoproteins (HDL) reduce the risk of atherosclerosis in humans. Apolipoprotein A-I (apoA-I) and apoA-II are the first and second most common protein constituents of HDL. Unlike apoA-I, detailed structural models for apoA-II in HDL are not available. Here, we present a structural model of apoA-II in reconstituted HDL (rHDL) based on two well established experimental approaches: chemical cross-linking/mass spectrometry (MS) and internal reflection infrared spectroscopy. Homogeneous apoA-II rHDL were reacted with a cross-linking agent to link proximal lysine residues. Upon tryptic digestion, cross-linked peptides were identified by electrospray mass spectrometry. 14 cross-links were identified and confirmed by tandem mass spectrometry (MS/MS). Infrared spectroscopy indicated a beltlike molecular arrangement for apoA-II in which the protein helices wrap around the lipid bilayer rHDL disc. The cross-links were then evaluated on three potential belt arrangements. The data clearly refute a parallel model but support two antiparallel models, especially a "double hairpin" form. These models form the basis for understanding apoA-II structure in more complex HDL particles.


Assuntos
Apolipoproteína A-II/química , Lipoproteínas HDL/química , Lipoproteínas/química , Apolipoproteína A-II/metabolismo , Reagentes de Ligações Cruzadas/metabolismo , Humanos , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Lipoproteínas/metabolismo , Lipoproteínas HDL/metabolismo , Estrutura Secundária de Proteína , Espectrofotometria Infravermelho , Relação Estrutura-Atividade
19.
J Microencapsul ; 22(2): 127-38, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16019899

RESUMO

Low encapsulation efficiency, incomplete and erratic release profiles are the most common features of controlled released protein delivery systems employing biodegradable polymers. In the present study, lysozyme as a model protein was encapsulated in biodegradable microspheres using solvent evaporation method and the effect of amphiphilic stabilizer, a basic salt and a lyoprotectant on microparticle formulation was evaluated. Incorporation rat serum albumin (RSA) in the internal aqueous phase during emulsion increased the encapsulation efficiency of lysozyme and maintained the bioactivity. Use of NaHCO3 improved the encapsulation efficiency of lysozyme from 15-94%, but at the cost of reduced in vitro release characteristics. Incorporation of both RSA and NaHCO3 improved the bioactivity of lysozyme and decreased burst release of the protein from the polymer particle, but reduced the encapsulation efficiency from 90-70%. Addition of sucrose in the internal aqueous phase lowered the encapsulation efficiency which was restored by its addition in the external aqueous phase. Maintenance of internal aqueous phase pH close to the iso-electric point of the protein and osmotic balance between the internal aqueous phase and the external aqueous phase during solvent evaporation method helped in better encapsulation of the protein drug. In vitro release of the lysozyme correlated with the effect of different excipients on entrapment in polymer matrix. Entrapment efficiency as high as 76%, low burst effect and high bioactivity of the entrapped lysozyme was observed from the polymer particles. Use of RSA, sucrose and NaHCO3 helped in a co-operative way towards the formulation of particles entrapping bioactive lysozyme.


Assuntos
Composição de Medicamentos/métodos , Microesferas , Muramidase , Absorção , Animais , Materiais Biocompatíveis , Biodegradação Ambiental , Preparações de Ação Retardada , Estabilidade de Medicamentos , Ácido Láctico , Tamanho da Partícula , Poliésteres , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros , Ratos , Albumina Sérica/farmacologia , Bicarbonato de Sódio/farmacologia , Sacarose/farmacologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-15319128

RESUMO

To protect against malleolar fractures in frontal crashes it is important to understand the mechanisms of injury. We have investigated the accuracy of Orthopaedic Specialists in deducing the injury mechanisms of experimentally generated malleolar fractures from radiographs; and the applicability of classic descriptors of injury mechanisms, such as the Lauge-Hansen classification system, in analysing impact induced trauma. Orthopaedic Specialists did not consistently deduce the mechanism of ankle injuries suggesting there may not be a unique fracture pattern for every injury mechanism and that the Lauge-Hansen classification system does not reliably describe ankle fractures created in the impact environment.


Assuntos
Acidentes de Trânsito , Traumatismos do Tornozelo/fisiopatologia , Fraturas Ósseas/fisiopatologia , Traumatismos do Tornozelo/classificação , Traumatismos do Tornozelo/diagnóstico por imagem , Fenômenos Biomecânicos , Ligamentos Colaterais/diagnóstico por imagem , Ligamentos Colaterais/lesões , Fraturas Ósseas/classificação , Fraturas Ósseas/diagnóstico por imagem , Humanos , Movimento , Pronação , Radiografia , Estudos Retrospectivos , Supinação
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