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1.
Healthcare (Basel) ; 11(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37046892

RESUMO

The university stage is a good time to promote healthy eating strategies. The sociological and cultural changes experienced by students lead them to skip meals, increase their intake of fast food and energy-dense foods, decreasing adherence to the Mediterranean diet (MD). Professionals related to food such as nutritionists and dietitians are also considered a population at risk of developing eating disorders due to the extensive knowledge they possess, which can be used for both good and bad practice. The objective was to analyze the impact of a 4-month educational program promoting the Mediterranean diet on risky eating behaviors, adherence to the Mediterranean diet, and body composition in nutrition and dietetics students, studying the differences according to the group investigated (control group and educated group). The context of the research was 196 students (49 males and 147 females) from two consecutive years. The control group did not receive any type of intervention, while with the control group (educated) an educational program was carried out. Results showed that women with greater control over energy intake, carbohydrates, and sugar had a lower percentage of fat mass, while in men, the relationship was established with weight. Regarding adherence to the Mediterranean diet, at post, it is adequate in both men (8.25 ± 2.87) and women (7.90 ± 2.89), with no significant differences between the intervention groups.

2.
Children (Basel) ; 10(2)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36832388

RESUMO

Low energy availability may precede or be caused by cognitive disturbances in professional athletes. Related psychological problems include disordered eating patterns, body shape preoccupation, depression or anxiety. The objective of this research was to evaluate the effects of different personalised dietary plans on psychological factors in young professional female handball players with low energy availability. This 12-week randomised clinical trial involved 21 female players aged 22 ± 4 years, 172.0 ± 5.4 cm and 68.4 ± 6.7 kg divided into three groups (FD: free diet; MD: Mediterranean diet; HAD: high antioxidant diet). Eating behaviour (Eating Attitude Test, EAT-26: diet, bulimia and oral control subscales), body image (Body Shape Questionnaire, BSQ) and mood state (Profile of Mode State, POMS: tension, vigour, anger, depression, fatigue) were assessed. All participants showed low energy availability (<30 kcal/lean mass per day). The different plans showed no significant differences between them but significant differences over time within groups for the variables: body image, Tension, Vigour and Depression (p < 0.05). Eating behaviour improved slightly but did not show statistically significant changes. Following an adequate nutritional planning for athletes seems to improve the mood and body perception of young female handball players. A longer intervention period is required to assess the differences between diets and improvement of other parameters.

3.
Metabolites ; 13(2)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36837787

RESUMO

Energy deficits are often observed in athletes, especially in female athletes, due to the high expenditure of sport and strict diets. Low energy availability can cause serious health problems and affect sport performance. The aim of this study was to evaluate the effects of different personalized dietary plans on physiological and physical factors related to energy deficit syndrome in female professional handball players. Twenty-one professional female handball players, aged 22 ± 4 years, 172.0 ± 5.4 cm and 68.4 ± 6.7 kg, divided into three groups (FD: free diet; MD: Mediterranean diet; and AD: high antioxidant diet), participated in this 12-week randomized controlled trial. Energy expenditure through indirect calorimetry, energy availability, 7 day dietary intake analysis, blood pressure, cholesterol, menstrual function, body composition by both anthropometry and bioelectrical impedance, and strength performance were assessed. All participants showed low energy availability (<30 kcal/lean mass per day); despite this, all had eumenorrhea. Significant improvements were found after the intervention in all components of body composition (p < 0.05). In the remaining variables, despite slight improvements, none were significant neither over time nor between the different groups. Low energy availability has been observed in all professional female handball players, which may lead to serious consequences. A longer period of intervention is required to assess the differences between diets and improvements in other parameters.

4.
Front Nutr ; 9: 838364, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35782929

RESUMO

Background: Gluten intolerance is a systemic process of autoimmune nature; it develops in genetically predisposed subjects with gluten ingestion. The only treatment for celiac disease (CD) is a lifelong strict gluten-free diet (GFD). This study was designed to evaluate adherence to a GFD, risk of an eating disorder, and nutritional status in adult CD patients undergoing different interventions. Methods: A total of 28 Spanish women, aged 40 years or more, took part in a randomized controlled trial. Each group received a different intervention: group 1, gluten-free nutrition plan + exercise (GFD + E); group 2, gluten-free nutrition plan (GFD); group 3, celiac controls (NO-GFD); and group 4, non-celiac controls (CONTROL). The training was prescribed by a sport scientist. It was based on resistance training with elastic bands; beforehand a warm-up was performed and the resistance was increased progressively. The variables studied were adherence to the GFD, risk of eating disorders, blood values, and body composition. Results: Celiac women with personalized nutritional planning presented greater adherence to a gluten-free diet (p < 0.001). Regarding leukocytes, significant differences were observed between the GFD and control groups (p = 0.004). Perimeters and folds did not decrease significantly. Conclusion: Women with celiac disease who follow an adapted and personalized diet have a better adherence to a GFD compared to those who follow a non-professional diet, and therefore have a better immune system status (blood leukocytes).

5.
Nutrients ; 14(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35276823

RESUMO

The period of Ramadan induces changes in the usual eating patterns of individuals. During this period, Muslims must abstain from drinking and eating from dawn to dusk. Therefore, some research conducted on professional soccer players has observed that during and/or after Ramadan, performance, running speed, agility, dribbling speed, and endurance and/or skill performance in athletic events may be negatively affected by Ramadan intermittent fasting (RIF). The objective of this study was to analyze the influence of a dietary plan during RIF on performance and body composition in a professional soccer player. A 20-year-old elite player (86.0 kg, 188.5 cm) followed a dietary-nutritional plan with an isocaloric diet and was supplemented with glycerol. The athlete's strength and power in the lower limbs was assessed by performing a countermovement jump (CMJ) and Abalakov vertical jump (ABK) before and after Ramadan. After nutritional planning, the patient's body composition improved in terms of fat loss (6.61 to 5.70%) and muscle mass gain (50.26 to 51.50%). In addition, this translated into improvements in performance tests, both in the CMJ (36.72 to 40.00 cm) and ABK (39.16 to 49.34 cm). In conclusion, during a period of fasting, personalised nutritional planning and an appropriate supplementation and rest protocol can improve the body composition and performance of soccer players.


Assuntos
Desempenho Atlético , Corrida , Futebol , Adulto , Desempenho Atlético/fisiologia , Jejum/fisiologia , Humanos , Islamismo , Corrida/fisiologia , Futebol/fisiologia , Adulto Jovem
6.
Gels ; 8(1)2022 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-35049585

RESUMO

Triathlons are endurance events that include swimming, running, and cycling. Triathletes need to eat optimally during training and competitions to maximize their potential for success. The presence of carbohydrates in the mouth could activate regions in the brain to enhance athletic performance in exercise. METHODS: This study examined the effects of glucose and mouthwash in ten male triathletes (age: 26.0 ± 8.7 years, height: 173.6 ± 10.4 cm, BMI 22.0 ± 1.7 kg/m2). The four oral test solutions included (A) Rinse with placebo, (B) Water + gel with placebo, (C) Rinse with 15% CH concentration, and (D) Water + gel with 15% CH concentration (25 g gel in 165 mL water). The Rate of Perceived Exertion (RPE), Sensation Scale (FS), Felt Arousal Scale (FAS), Profile of Mood States (POMS), blood glucose, sprints, and dietary habits were assessed in each subject. All preceded ingestion of the oral-based test solution during workouts. RESULTS: RPE showed no significant differences for subjective perceptions. The same was observed for FS and sprints. FAS scores increased over time (p = 0.039) in all groups. POMS score increased significantly in group D (p = 0.041). There was no effect of time on plasma glucose levels (p = 0.737). As for correlations, positive correlations were observed between sprint and FAS variables (p = 0.011). CONCLUSIONS: It appears that CH intake correlates positively with mood, but in all other variables, there are no differences depending on the product.

7.
Nutrients ; 15(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36615795

RESUMO

Women's elite sports have experienced an exponential increase in the last decade, as has beach handball (BH). The high demands of this sport mean that athletes need to be in superior physical condition, so nutrition and body composition are determining factors in their sporting performance. For this reason, the aim of this study was to analyze, compare and correlate the most relevant variables of food intake (quantitative), body composition (focus on the bone mass characteristics) and sprint performance in female professional BH players. Thirty-three women from the National Spanish Team participated in this study. Dietary assessment, anthropometric measurements and sprint tests were performed. In general, the players had a low carbohydrate intake and adequate protein intake, with no significant differences depending on the category and playing position. For senior players, positive correlations were found between protein intake and bone mass (r = 0.584, p = 0.022), polyunsaturated fatty acid intake and muscle mass (r = 0.387, p = 0.026) and finally between fat mass and animal protein intake (r = 0.569, p = 0.027). Body composition was similar in both categories; however, goalkeepers had the highest fat (22.6 ± 3.86%, 16.2 ± 4.84 kg) component (vs. wings: 17.4 ± 3.53%, p = 0.031/vs. specialists: 11.1 ± 1.91 kg, p = 0.034), and senior players had higher muscle mass (kilograms). It is worth noting the finding that players with a greater trochanter height had significantly lower sprint times (p = 0.014 and p = 0.048 for 5 and 10 m, respectively). Certain bone characteristics, such as iliospinale height, biacromial and bimalleolar diameters, mesosternal perimeter and biceps skinfold, differ depending on the position. In addition, the greater speed of the senior players may be due to the greater specialization, number of training sessions performed and specific bone characteristics, such as trochanter height. In this regard, the data provided in this study will assist with establishing criteria for the selection of talent for this sporting discipline.


Assuntos
Desempenho Atlético , Feminino , Humanos , Desempenho Atlético/fisiologia , Composição Corporal/fisiologia , Atletas , Braço , Dieta , Antropometria
8.
Nanomedicine ; 13(2): 569-581, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27720925

RESUMO

Two-component systems (TCS) regulate diverse processes such as virulence, stress responses, metabolism and antibiotic resistance in bacteria but are absent in humans, making them promising targets for novel antibacterials. By incorporating recently described TCS histidine kinase autophosphorylation inhibitors (HKAIs) into ε-poly-L-lysine capped nanoparticles (NPs) we could overcome the Gram negative (Gr-) permeability barrier for the HKAIs. The observed bactericidal activity against Gr- bacteria was shown to be due to the enhanced delivery and internalization of the HKAIs and not an inhibitory or synergistic effect of the NPs. The NPs had no adverse effects on mammalian cell viability or the immune function of macrophages in vitro and showed no signs of toxicity to zebrafish larvae in vivo. These results show that HKAIs are promising antibacterials for both Gr- and Gr+pathogens and that NPs are a safe drug delivery technology that can enhance the selectivity and efficacy of HKAIs against bacteria.


Assuntos
Antibacterianos/farmacologia , Histidina Quinase , Nanopartículas , Dióxido de Silício , Animais , Sistemas de Liberação de Medicamentos , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Histidina , Humanos , Lisina
9.
Bioconjug Chem ; 27(5): 1276-84, 2016 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-27098672

RESUMO

A disulfide-bridged peptide drug development candidate contained two oligopeptide chains with 11 and 12 natural amino acids joined by a disulfide bond at the N-terminal end. An efficient biotechnology based process for the production of the disulfide-bridged peptide was developed. Initially, the two individual oligopeptide chains were prepared separately by designing different fusion proteins and expressing them in recombinant E. coli. Enzymatic or chemical cleavage of the two fusion proteins provided the two individual oligopeptide chains which could be conjugated via disulfide bond by conventional chemical reaction to the disulfide-bridged peptide. A novel heterodimeric system to bring the two oligopeptide chains closer and induce disulfide bond formation was designed by taking advantage of the self-assembly of a leucine zipper system. The heterodimeric approach involved designing fusion proteins with the acidic and basic components of the leucine zipper, additional amino acids to optimize interaction between the individual chains, specific cleavage sites, specific tag to ensure separation, and two individual oligopeptide chains. Computer modeling was used to identify the nature and number of amino acid residue to be inserted between the leucine zipper and oligopeptides for optimum interaction. Cloning and expression in rec E. coli, fermentation, followed by cell disruption resulted in the formation of heterodimeric protein with the interchain disulfide bond. Separation of the desired heterodimeric protein, followed by specific cleavage at methionine by cyanogen bromide provided the disulfide-bridged peptide.


Assuntos
Biotecnologia , Dissulfetos/química , Peptídeos/química , Peptídeos/metabolismo , Sequência de Aminoácidos , Escherichia coli/genética , Modelos Moleculares , Peptídeos/genética , Multimerização Proteica , Estrutura Quaternária de Proteína
10.
Langmuir ; 32(5): 1195-200, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26794474

RESUMO

The possibility of achieving sophisticated actions in complex biological environments using gated nanoparticles is an exciting prospect with much potential. We herein describe new gated mesoporous silica nanoparticles (MSN) loaded with an anticoagulant drug and capped with a peptide containing a thrombin-specific cleavage site. When the coagulation cascade was triggered, active thrombin degraded the capping peptidic sequence and induced the release of anticoagulant drugs to delay the clotting process. The thrombin-dependent response was assessed and a significant increase in coagulation time in plasma from 2.6 min to 5 min was found. This work broadens the application of gated silica nanoparticles and demonstrates their ability to act as controllers in a complex scenario such as hemostasis.


Assuntos
Acenocumarol/química , Anticoagulantes/química , Nanopartículas/química , Dióxido de Silício/química , Trombina/química , Acenocumarol/farmacologia , Animais , Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Ácidos Pentanoicos/química , Coelhos , Tempo de Coagulação do Sangue Total
11.
PDA J Pharm Sci Technol ; 70(3): 272-81, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26797969

RESUMO

Air-liquid interface rings were observed on the side walls of stainless steel buffer vessels after certain downstream buffer preparations. Those rings were resistant to regular cleaning-in-place procedures but could be removed by manual means. To investigate the root cause of this issue, multiple analytical techniques, including liquid chromatography with tandem mass spectrometry detection (LC-MS/MS), high-resolution accurate mass liquid chromatography with mass spectrometry, nuclear magnetic resonance, Fourier transform infrared spectroscopy, and scanning electron microscopy with energy-dispersive X-ray spectroscopy have been employed to characterize the chemical composition of air-liquid interface rings. The main component of air-liquid interface rings was determined to be slip agents, and the origin of the slip agents can be traced back to their presence on raw material packaging liners. Slip agents are commonly used in plastic industry as additives to reduce the coefficient of friction during the manufacturing process of thin films. To mitigate this air-liquid interface ring issue, an alternate liner with low slip agent was identified and implemented with minimal additional cost. We have also proactively tested the packaging liners of other raw materials currently used in our downstream buffer preparation to ensure slip agent levels are appropriate. LAY ABSTRACT: Air-liquid interface rings were observed on the side walls of stainless steel buffer vessels after certain downstream buffer preparations. To investigate the root cause of this issue, multiple analytical techniques have been employed to characterize the chemical composition of air-liquid interface rings. The main components of air-liquid interface rings were determined to be slip agents, which are common additives used in the manufacturing process of thin films. The origin of the slip agents can be traced back to their presence on certain raw material packaging liners. To mitigate this air-liquid interface ring issue, an alternate liner with low slip agent was identified and implemented.


Assuntos
Química Farmacêutica/métodos , Embalagem de Medicamentos/métodos , Preparações Farmacêuticas , Aço Inoxidável , Soluções Tampão , Química Farmacêutica/instrumentação , Cromatografia Líquida/instrumentação , Cromatografia Líquida/métodos , Embalagem de Medicamentos/instrumentação , Espectroscopia de Ressonância Magnética/instrumentação , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Preparações Farmacêuticas/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Propriedades de Superfície
12.
Int J Health Serv ; 45(1): 53-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26460447

RESUMO

The increasing financial pressures of health care insurance coverage have become a key issue for advanced economies. This study tests whether hospital financial pressures have an effect on the health of the uninsured population. To do so, the author investigates the implications of managed care for the uninsured in the United States. Managed care penetration has increased financial pressures on hospitals, and previous work has shown that safety net hospitals have been affected more severely. The study results reveal that charity care patients concentrate in government hospitals in areas where financial pressures imposed by managed care are greater. In addition, the quality of care of these hospitals decreases more in areas where managed care penetration is stronger. Finally, the stronger financial pressures that managed care diffusion imposes have a negative effect on the quality of care the uninsured and those admitted to government hospitals receive.


Assuntos
Hospitais Públicos/economia , Programas de Assistência Gerenciada/estatística & dados numéricos , Pessoas sem Cobertura de Seguro de Saúde/estatística & dados numéricos , Qualidade da Assistência à Saúde/estatística & dados numéricos , Cuidados de Saúde não Remunerados/economia , Humanos , Modelos Econométricos , Indicadores de Qualidade em Assistência à Saúde , Provedores de Redes de Segurança/economia , Estados Unidos
13.
Small ; 10(23): 4859-64, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25079146

RESUMO

A new approach towards the design of "gated scaffolds" based on the combination of capped mesoporous silica nanoparticles (MSNs) with porous biomaterials is reported. Using this approach, a 3D gelatin-based scaffold able to selectively deliver cargo in the presence of an APase enzyme is prepared and tested. This new design opens up the possibility of developing new smart biomaterials with advanced drug-delivery features.


Assuntos
Materiais Biocompatíveis/química , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Imageamento Tridimensional/métodos , Trifosfato de Adenosina/química , Ânions , Géis/química , Ligação de Hidrogênio , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanopartículas/química , Nanotecnologia/métodos , Porosidade , Regeneração , Dióxido de Silício/química , Engenharia Tecidual/métodos , Difração de Raios X
14.
Int J Nanomedicine ; 9: 2597-606, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24920897

RESUMO

pH-sensitive gated mesoporous silica nanoparticles have been synthesized. Increased extracellular pH and internalization into living yeast cells triggered molecular gate aperture and cargo release. Proper performance of the system was demonstrated with nanodevices loaded with fluorescein or with the antifungal agent tebuconazole. Interestingly, nanodevices loaded with tebuconazole significantly enhanced tebuconazole cytotoxicity. As alterations of acidic external pH are a key parameter in the onset of fungal vaginitis, this nanodevice could improve the treatment for vaginal mycoses.


Assuntos
Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Nanocápsulas/química , Nanoporos/ultraestrutura , Saccharomyces cerevisiae/efeitos dos fármacos , Triazóis/administração & dosagem , Antifúngicos/administração & dosagem , Antifúngicos/química , Sobrevivência Celular/efeitos dos fármacos , Difusão , Sinergismo Farmacológico , Concentração de Íons de Hidrogênio , Nanocápsulas/administração & dosagem , Nanocápsulas/ultraestrutura , Tamanho da Partícula , Porosidade , Saccharomyces cerevisiae/fisiologia , Triazóis/química
15.
Chemistry ; 20(18): 5271-81, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24700694

RESUMO

The synthesis and characterization of two new capped silica mesoporous nanoparticles for controlled delivery purposes are described. Capped hybrid systems consist of MCM-41 nanoparticles functionalized on the outer surface with polymer ε-poly-L-lysine by two different anchoring strategies. In both cases, nanoparticles were loaded with model dye molecule [Ru(bipy)3](2+). An anchoring strategy involved the random formation of urea bonds by the treatment of propyl isocyanate-functionalized MCM-41 nanoparticles with the lysine amino groups located on the ε-poly-L-lysine backbone (solid Ru-rLys-S1). The second strategy involved a specific attachment through the carboxyl terminus of the polypeptide with azidopropyl-functionalized MCM-41 nanoparticles (solid Ru-tLys-S1). Once synthesized, both nanoparticles showed a nearly zero cargo release in water due to the coverage of the nanoparticle surface by polymer ε-poly-L-lysine. In contrast, a remarkable payload delivery was observed in the presence of proteases due to the hydrolysis of the polymer's amide bonds. Once chemically characterized, studies of the viability and the lysosomal enzyme-controlled release of the dye in intracellular media were carried out. Finally, the possibility of using these materials as drug-delivery systems was tested by preparing the corresponding ε-poly-L-lysine capped mesoporous silica nanoparticles loaded with cytotoxic drug camptothecin (CPT), CPT-rLys-S1 and CPT-tLys-S1. Cellular uptake and cell-death induction were studied. The efficiency of both nanoparticles as new potential platforms for cancer treatment was demonstrated.


Assuntos
Preparações de Ação Retardada/química , Nanopartículas/química , Polilisina/química , Dióxido de Silício/química , Linhagem Celular Tumoral , Corantes/administração & dosagem , Preparações de Ação Retardada/metabolismo , Células HeLa , Humanos , Lisossomos/enzimologia , Nanopartículas/metabolismo , Nanopartículas/ultraestrutura , Polilisina/metabolismo , Porosidade , Rutênio/administração & dosagem , Dióxido de Silício/metabolismo
16.
Chemistry ; 19(34): 11167-71, 2013 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-23839913

RESUMO

Bug busters: A novel nanodevice consisting of mesoporous nanoparticles loaded with vancomycin and capped with ε-poly-L-lysine (ε-PL) was prepared and its interaction with different Gram-negative bacteria studied. A remarkable improvement in the efficacy of the antimicrobial drug ε-PL and a broadening of the antimicrobial spectrum of vancomycin is demonstrated.


Assuntos
Antibacterianos/química , Nanopartículas/química , Vancomicina/química , Antibacterianos/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Polilisina/química , Porosidade , Dióxido de Silício/química
17.
Int J Health Care Finance Econ ; 13(2): 95-114, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23389814

RESUMO

Healthcare financing and insurance is changing everywhere. We want to understand the impact that financial pressures can have for the uninsured in advanced economies. To do so we focus on analyzing the effect of the introduction in the US of managed care and the big rise in financial pressures that it implied. Traditionally, in the US safety net hospitals have financed their provision of unfunded care through a complex system of cross-subsidies. Our hypothesis is that financial pressures undermine the ability of a hospital to cross-subsidize and challenges their survival. We focus on the impact of price pressures and cost-controlling mechanisms imposed by managed care. We find that financial pressures imposed by managed care disproportionately affect the closure of safety net hospitals. Moreover, amongst those hospitals that remain open, in areas where managed care penetration increases the most, they react by closing the health services most commonly used by the uninsured.


Assuntos
Economia Hospitalar , Programas de Assistência Gerenciada/economia , Cuidados de Saúde não Remunerados , Controle de Custos , Economia Hospitalar/organização & administração , Economia Hospitalar/estatística & dados numéricos , Fechamento de Instituições de Saúde/economia , Fechamento de Instituições de Saúde/estatística & dados numéricos , Humanos , Pessoas sem Cobertura de Seguro de Saúde , Provedores de Redes de Segurança/economia , Provedores de Redes de Segurança/estatística & dados numéricos , Cuidados de Saúde não Remunerados/economia , Estados Unidos
18.
Chemistry ; 19(4): 1346-56, 2013 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-23225567

RESUMO

The preparation of a new capped silica mesoporous material, Rh-Azo-S, for on-command delivery applications in the presence of target enzymes is described. The material consists of nanometric mesoporous MCM-41-like supports loaded with Rhodamine B and capped with an azopyridine derivative. The material was designed to show "zero delivery" and to display a cargo release in the presence of reductases and esterases, which are usually present in the colon, mainly due to intestinal microflora. The opening and cargo release of Rh-Azo-S in vitro studies were assessed and seen to occur in the presence of these enzymes, whereas no delivery was noted in the presence of pepsine. Moreover, Rh-Azo-S nanoparticles were used to study controlled Rhodamine B dye delivery in intracellular media. HeLa cells were employed for testing the "non"-toxicity of nanoparticles. Moreover, delivery of the dye in these cells, through internalization and enzyme-mediated gate opening, was confirmed by confocal microscopy. Furthermore, the nanoparticles capped with the Azo group and loaded with a cytotoxic camptothecin (CPT) were also prepared (solid CPT-Azo-S) and used as delivery nanodevices in HeLa cells. When this solid was employed, the cell viability decreased significantly due to internalization of the nanoparticles and delivery of the cytotoxic agent.


Assuntos
Compostos Azo/química , Oxirredutases/metabolismo , Piridinas/química , Compostos de Piridínio/química , Dióxido de Silício/química , Compostos Azo/síntese química , Compostos Azo/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Células MCF-7 , Nanopartículas/química , Oxirredutases/química , Porosidade , Compostos de Piridínio/síntese química , Compostos de Piridínio/toxicidade , Rodaminas/química
19.
Biotechnol Lett ; 35(3): 323-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23160743

RESUMO

As part of the process-characterization campaign of a candidate vaccine product, a recently developed class of three-level designs-definitive-screening designs-was employed to select a quadratic model that describes the effect of six input process parameters, including protein concentration, formaldehyde-to-protein ratio, lysine concentration, reaction duration, pH, and reaction temperature, on a formylation protein-crosslinking reaction. This design requires only 17 experimental runs. The resulting model was then used to simulate 10,000 runs that account for the variability in the inputs expected on manufacturing scale. The extent of protein polymerization was predicted to be within specifications for all simulated runs, demonstrating the robustness of the unit operation for subsequent process validation and future commercial manufacturing.


Assuntos
Produtos Biológicos/isolamento & purificação , Produtos Biológicos/metabolismo , Biotecnologia/métodos , Proteínas/isolamento & purificação , Proteínas/metabolismo , Tecnologia Farmacêutica/métodos , Projetos de Pesquisa
20.
Chemistry ; 18(41): 13068-78, 2012 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-22927363

RESUMO

The synthesis and characterisation of new capped silica mesoporous nanoparticles for on-command delivery applications is reported. Functional capped hybrid systems consist of MCM-41 nanoparticles functionalised on the external surface with polyesters bearing azobenzene derivatives and rhodamine B inside the mesopores. Two solid materials, Rh-PAzo8-S and Rh-PAzo6-S, containing two closely related polymers, PAzo8 and PAzo6, in the pore outlets have been prepared. Materials Rh-PAzo8-S and Rh-PAzo6-S showed an almost zero release in water due to steric hindrance imposed by the presence of anchored bulky polyesters, whereas a large delivery of the cargo was observed in the presence of an esterase enzyme due to the progressive hydrolysis of polyester chains. Moreover, nanoparticles Rh-PAzo8-S and Rh-PAzo6-S were used to study the controlled release of the dye in intracellular media. Nanoparticles were not toxic for HeLa cells and endocytosis-mediated cell internalisation was confirmed by confocal microscopy. Furthermore, the possible use of capped materials as a drug-delivery system was demonstrated by the preparation of a new mesoporous silica nanoparticle functionalised with PAzo6 and loaded with the cytotoxic drug camptothecin (CPT-PAzo6-S). Following cell internalisation and lysosome resident enzyme-dependent gate opening, CPT-PAzo6-S induced CPT-dependent cell death in HeLa cells.


Assuntos
Compostos Azo/química , Camptotecina/química , Camptotecina/toxicidade , Nanopartículas/química , Poliésteres/química , Dióxido de Silício/química , Sistemas de Liberação de Medicamentos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Porosidade
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