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1.
Fish Shellfish Immunol ; 140: 108928, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37423403

RESUMO

The probiotic potential of a designed bacterial consortia isolated from a competitive exclusion culture originally obtained from the intestinal contents of tilapia juveniles were evaluated on Nile tilapia alevins. The growth performance, intestinal histology, microbiota effects, resistance to Streptococcus agalactiae challenge, and immune response were assessed. In addition, the following treatments were included in a commercial feed: A12+M4+M10 (Lactococcus lactis A12, Priestia megaterium M4, and Priestia sp. M10), M4+M10 (P. megaterium M4, and Priestia sp. M10) and the single bacteria as controls; A12 (L. lactis A12), M4 (P. megaterium M4), M10 (Priestia sp. M10), also a commercial feed without any probiotic addition was included as a control. The results showed that all probiotic treatments improved the growth performance, intestinal histology, and resistance during experimental infection with S. agalactiae in comparison to the control fish. Also, the administration of probiotics resulted in the modulation of genes associated with the innate and adaptive immune systems that were non-dependent on microbial colonization. Surprisingly, L. lactis A12 alone induced benefits in fish compared to the microbial consortia, showing the highest increase in growth rate, survival during experimental infection with S. agalactiae, increased intestinal fold length, and the number of differentially expressed genes. Lastly, we conclude that a competitive exclusion culture is a reliable source of probiotics, and monostrain L. lactis A12 has comparable or even greater probiotic potential than the bacterial consortia.


Assuntos
Ciclídeos , Doenças dos Peixes , Microbioma Gastrointestinal , Probióticos , Tilápia , Animais , Probióticos/farmacologia , Dieta/veterinária , Ração Animal/análise , Suplementos Nutricionais
2.
Acta Ortop Bras ; 30(6): e256947, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36561477

RESUMO

Objective: To determine the efficiency of the deep venous thrombosis (DVT) prophylaxis protocol in postoperative patients due to proximal femoral fractures and to assess any statistical difference between the types of fractures. Methods: A retrospective observational study based on the analysis of patients' medical records who underwent to a surgical intervention due to proximal femoral fractures in 2017 and 2021 at Hospital IFOR - Rede D'Or São Luiz. These patients were selected according to previously determined inclusion and exclusion criteria. A total of 99 patients were included divided by sex, age, laterality, length of stay, and death. According to the institutional protocol, was used chemoprophylaxis with low-molecular-weight heparin, associated use of pneumatic compression with compression stockings, and early gait. The DVT diagnosis was determined by clinical evaluation and imaging tests such as venous Doppler ultrasonography and laboratory tests. Results: The protocol was effective in our study. Only one (1.01%) patient developed DVT. Due to the lack of samples, we could not achieve our secondary objective. Conclusion: The institutional protocol is efficient for DVT prophylaxis and essential in these cases. Level of Evidence II, Prognostic Study.


Objetivo: Determinar a eficiência do protocolo de profilaxia contra trombose venosa profunda (TVP) em pacientes de pós-operatório devido à fratura do fêmur proximal e avaliar a diferença estatística entre os tipos de fratura. Método: Estudo retrospectivo observacional a partir da análise de prontuários de pacientes submetidos à intervenção cirúrgica em razão de fratura do fêmur proximal no período de 2017 e 2021 no Hospital IFOR - Rede D'Or São Luiz. Foram selecionados 99 pacientes segundo critérios de inclusão e exclusão determinados previamente, que foram catalogados por: idade, sexo, lateralidade, dias de internação, entre outros. Conforme protocolo institucional, utilizou-se quimioprofilaxia com heparina de baixo peso molecular, associado ao uso concomitante de compressão pneumática e meias elásticas, e deambulação precoce. O diagnóstico de TVP foi determinado por meio de avaliação clínica e exames de imagem, como a ultrassonografia com Doppler venoso e exames laboratoriais. Resultados: A utilização do protocolo se mostrou eficaz neste estudo, havendo apenas um paciente (1,01%) que desenvolveu TVP. Não foi possível atingir o objetivo secundário, pois a amostragem foi insuficiente. Conclusão: O protocolo institucional para a profilaxia de TVP foi eficiente, uma vez que apenas um paciente evoluiu com tal complicação. Nível de Evidência II, Estudo Prognóstico.

3.
Acta Ortop Bras ; 30(6): e257229, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36561479

RESUMO

Objective: Evaluating intra- and inter-observer agreement of the Neer, AO, and AO/OTA proximal humerus fractures classification systems in adults. Methods: In total, 100 X-rays of patients with proximal humerus fractures were selected according to the inclusion and exclusion criteria established in this study. They were evaluated by four evaluators with different levels of expertise. The evaluation was performed at two distinct moments, with an interval of 21 days between each analysis. Images were randomized for the second evaluation by a researcher who did not participate in the image selection process. A Fleiss Kappa test was performed to evaluate intra- and inter-observer agreement. Results: We observed a substantial agreement with k = 0.669, k = 0.715, and k = 0.780 for the Neer, AO, and AO/OTA classification systems, respectively. Conclusion: In the second evaluation, intra-observer agreement improved. In the first evaluation, we obtained values of k = 0.724, k = 0.490, and k = 0.599 for the evaluation of the Neer, AO, and AO/OTA classifications. In the second evaluation, the values k = 0.759, k = 0.772, and k = 0.858. Therefore, the evaluations went from moderate to substantial for the AO classification and from moderate to practically perfect for the AO/OTA classification. The level of inter-observer agreement was substantial (0.61-0.80), with k = 0.669, k = 0.715, and k = 0.780 for the Neer, AO, and AO/OTA classifications, respectively. Level of Evidence III, Cross-Sectional Observational Study.


Objetivo: Avaliar a concordância intra e interobservadores entre os sistemas de classificação Neer, AO e AO/OTA nas fraturas do úmero proximal de indivíduos adultos. Métodos: Após a aplicação dos critérios de inclusão e exclusão determinados para a realização deste trabalho, foram selecionadas 100 radiografias de pacientes com fratura do úmero proximal. Estas foram submetidas à avaliação de quatro examinadores com níveis diferentes de expertise. A avaliação foi realizada em dois momentos distintos, com intervalo de 21 dias entre cada análise. As imagens foram randomizadas para a segunda avaliação por um pesquisador que não participou da seleção de imagens. Foi aplicado o teste kappa de Fleiss para verificar a concordância intra e interobservador. Resultados: Na primeira avaliação obtivemos valores de k = 0,724, k = 0,490 e k = 0,599, enquanto na segunda avaliação, os valores k = 0,759, k = 0,772 e k = 0,858 para as avaliações de Neer, AO e AO/OTA, respectivamente. Isso indica que a concordância intraobservador melhorou na segunda avaliação. Conclusões: As avaliações passaram de moderada para substancial para a classificação AO e de moderada para praticamente perfeita para o sistema AO/OTA. O nível de concordância interobservadores foram considerados substanciais (0,61-0,80) com k = 0,669, k = 0,715 e k = 0,780 para as classificações de Neer, AO e AO/OTA, respectivamente. Nível de Evidência III, Estudo Transversal Observacional.

4.
ScientificWorldJournal ; 2022: 6420003, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36419778

RESUMO

Polyvinyl chloride (PVC) is widely used in industrial applications, such as construction and clothing, owing to its chemical, physical, and environmental resistance. Owing to the previous characteristics, PVC is the third most consumed plastic worldwide and, consequently, an increasing waste accumulation-related problem. The current study evaluated an in-house collection of 61 Actinobacteria strains for PVC resin biodegradation. Weight loss percentage was measured after the completion of incubation. Thermo-gravimetric analysis was subsequently performed using the PVC incubated with the three strains exhibiting the highest weight loss. GC-MS and ionic exchange chromatography analyses were also performed using the culture media supernatant of these three strains. After incubation, 14 strains had a PVC weight loss percentage higher than 50% in ISP-2 broth. These 14 strains were identified as Streptomyces strains. Strains 208, 250, and 290 showed the highest weight loss percentages (57.6-61.5% range). The thermal stability of PVC after bacterial exposure using these three strains was evaluated, and a modification of the representative degradation stages of nonincubated PVC was observed. Additionally, GC-MS analysis revealed the presence of aromatic compounds in the inoculated culture media, and ionic exchange chromatography showed chloride release in the supernatant. A mathematical relation between culture conditions and PVC weight loss was also found for strains 208 and 290, showing an accuracy up to 97.99%. These results highlight the potential of the freshwater-derived Streptomyces strains as candidates for the PVC biodegradation strategy and constitute the first approach to a waste management control scale-up process.


Assuntos
Cloreto de Polivinila , Streptomyces , Humanos , Cloreto de Polivinila/química , Estudos Prospectivos , Água Doce , Meios de Cultura , Redução de Peso
5.
Polymers (Basel) ; 14(15)2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35893955

RESUMO

Dressings made with polyurethanes have been found to exhibit good and varied biological properties that make them good candidates for this application. However, as has been seen, the wound-healing process is complex, which includes four different stages. So far, the design and evaluation of polyurethane for wound dressing has focused on achieving good properties (mechanical, physicochemical, and biological), but each of them separates from the others or even directed at only one of the stages of skin wound-healing. Therefore, the aim of this systematic review is to explore the applications of polyurethanes in wound dressings and to determine whether could be designed to cover more than one stage of skin wound-healing. The PRISMA guidelines were followed. The current research in this field does not consider each stage separately, and the design of polyurethane dressings is focused on covering all the stages of wound healing with a single material but is necessary to replace polyurethanes in short periods of time. Additionally, little emphasis is placed on the hemostasis stage and further characterization of polyurethanes is still needed to correlate mechanical and physicochemical properties with biological properties at each stage of the wound-healing. Current research demonstrates an effort to characterize the materials physiochemically and mechanically, but in terms of their biological properties, most of the literature is based on the performance of histological tests of explants morphologically probing the compromised tissues, which give an indication of the potential use of polyurethanes in the generation of wound-healing dressings.

6.
Plants (Basel) ; 11(10)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35631782

RESUMO

The use of cannabis and cannabinoid products for the treatment of neuropathic pain is a growing area of research. This type of pain has a high prevalence, limited response to available therapies and high social and economic costs. Systemic cannabinoid-based therapies have shown some unwanted side effects. Alternative routes of administration in the treatment of neuropathic pain may provide better acceptance for the treatment of multiple pathologies associated with neuropathic pain. To examine the efficacy, tolerability, and safety of cannabinoids (individualized formulations, phytocannabinoids, and synthetics) administered by routes other than oral or inhalation compared to placebo and/or conventional medications in the management of neuropathic pain. This systematic review of the literature reveals a lack of clinical research investigating cannabis by routes other than oral and inhalation as a potential treatment for neuropathic pain and highlights the need for further investigation with well-designed clinical trials. There is a significant lack of evidence indicating that cannabinoids administered by routes other than oral or inhaled may be an effective alternative, with better tolerance and safety in the treatment of neuropathic pain. Higher quality, long-term, randomized controlled trials are needed to examine whether cannabinoids administered by routes other than inhalation and oral routes may have a role in the treatment of neuropathic pain.

7.
Acta ortop. bras ; 30(6): e257229, 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1419955

RESUMO

ABSTRACT Objective: Evaluating intra- and inter-observer agreement of the Neer, AO, and AO/OTA proximal humerus fractures classification systems in adults. Methods: In total, 100 X-rays of patients with proximal humerus fractures were selected according to the inclusion and exclusion criteria established in this study. They were evaluated by four evaluators with different levels of expertise. The evaluation was performed at two distinct moments, with an interval of 21 days between each analysis. Images were randomized for the second evaluation by a researcher who did not participate in the image selection process. A Fleiss Kappa test was performed to evaluate intra- and inter-observer agreement. Results: We observed a substantial agreement with k = 0.669, k = 0.715, and k = 0.780 for the Neer, AO, and AO/OTA classification systems, respectively. Conclusion: In the second evaluation, intra-observer agreement improved. In the first evaluation, we obtained values of k = 0.724, k = 0.490, and k = 0.599 for the evaluation of the Neer, AO, and AO/OTA classifications. In the second evaluation, the values k = 0.759, k = 0.772, and k = 0.858. Therefore, the evaluations went from moderate to substantial for the AO classification and from moderate to practically perfect for the AO/OTA classification. The level of inter-observer agreement was substantial (0.61-0.80), with k = 0.669, k = 0.715, and k = 0.780 for the Neer, AO, and AO/OTA classifications, respectively. Level of Evidence III, Cross-Sectional Observational Study.


RESUMO Objetivo: Avaliar a concordância intra e interobservadores entre os sistemas de classificação Neer, AO e AO/OTA nas fraturas do úmero proximal de indivíduos adultos. Métodos: Após a aplicação dos critérios de inclusão e exclusão determinados para a realização deste trabalho, foram selecionadas 100 radiografias de pacientes com fratura do úmero proximal. Estas foram submetidas à avaliação de quatro examinadores com níveis diferentes de expertise. A avaliação foi realizada em dois momentos distintos, com intervalo de 21 dias entre cada análise. As imagens foram randomizadas para a segunda avaliação por um pesquisador que não participou da seleção de imagens. Foi aplicado o teste kappa de Fleiss para verificar a concordância intra e interobservador. Resultados: Na primeira avaliação obtivemos valores de k = 0,724, k = 0,490 e k = 0,599, enquanto na segunda avaliação, os valores k = 0,759, k = 0,772 e k = 0,858 para as avaliações de Neer, AO e AO/OTA, respectivamente. Isso indica que a concordância intraobservador melhorou na segunda avaliação. Conclusões: As avaliações passaram de moderada para substancial para a classificação AO e de moderada para praticamente perfeita para o sistema AO/OTA. O nível de concordância interobservadores foram considerados substanciais (0,61-0,80) com k = 0,669, k = 0,715 e k = 0,780 para as classificações de Neer, AO e AO/OTA, respectivamente. Nível de Evidência III, Estudo Transversal Observacional.

8.
Acta ortop. bras ; 30(6): e256947, 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1419959

RESUMO

ABSTRACT Objective: To determine the efficiency of the deep venous thrombosis (DVT) prophylaxis protocol in postoperative patients due to proximal femoral fractures and to assess any statistical difference between the types of fractures. Methods: A retrospective observational study based on the analysis of patients' medical records who underwent to a surgical intervention due to proximal femoral fractures in 2017 and 2021 at Hospital IFOR - Rede D'Or São Luiz. These patients were selected according to previously determined inclusion and exclusion criteria. A total of 99 patients were included divided by sex, age, laterality, length of stay, and death. According to the institutional protocol, was used chemoprophylaxis with low-molecular-weight heparin, associated use of pneumatic compression with compression stockings, and early gait. The DVT diagnosis was determined by clinical evaluation and imaging tests such as venous Doppler ultrasonography and laboratory tests. Results: The protocol was effective in our study. Only one (1.01%) patient developed DVT. Due to the lack of samples, we could not achieve our secondary objective. Conclusion: The institutional protocol is efficient for DVT prophylaxis and essential in these cases. Level of Evidence II, Prognostic Study.


RESUMO Objetivo: Determinar a eficiência do protocolo de profilaxia contra trombose venosa profunda (TVP) em pacientes de pós-operatório devido à fratura do fêmur proximal e avaliar a diferença estatística entre os tipos de fratura. Método: Estudo retrospectivo observacional a partir da análise de prontuários de pacientes submetidos à intervenção cirúrgica em razão de fratura do fêmur proximal no período de 2017 e 2021 no Hospital IFOR - Rede D'Or São Luiz. Foram selecionados 99 pacientes segundo critérios de inclusão e exclusão determinados previamente, que foram catalogados por: idade, sexo, lateralidade, dias de internação, entre outros. Conforme protocolo institucional, utilizou-se quimioprofilaxia com heparina de baixo peso molecular, associado ao uso concomitante de compressão pneumática e meias elásticas, e deambulação precoce. O diagnóstico de TVP foi determinado por meio de avaliação clínica e exames de imagem, como a ultrassonografia com Doppler venoso e exames laboratoriais. Resultados: A utilização do protocolo se mostrou eficaz neste estudo, havendo apenas um paciente (1,01%) que desenvolveu TVP. Não foi possível atingir o objetivo secundário, pois a amostragem foi insuficiente. Conclusão: O protocolo institucional para a profilaxia de TVP foi eficiente, uma vez que apenas um paciente evoluiu com tal complicação. Nível de Evidência II, Estudo Prognóstico.

9.
Bioengineering (Basel) ; 8(11)2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34821720

RESUMO

The inherent resistance of synthetic plastics to degradation has led to an increasing challenge of waste accumulation problem and created a pollution issue that can only be addressed with novel complementary methods such as biodegradation. Since biocontrol is a promising eco-friendly option to address this challenge, the identification of suitable biological agents is a crucial requirement. Among the existing options, organisms of the Streptomyces genus have been reported to biodegrade several complex polymeric macromolecules such as chitin, lignin, and cellulose. Therefore, this systematic review aimed to evaluate the potential of Streptomyces strains for the biodegradation of synthetic plastics. The results showed that although Streptomyces strains are widely distributed in different ecosystems in nature, few studies have explored their capacity as degraders of synthetic polymers. Moreover, most of the research in this field has focused on Streptomyces strains with promising biotransforming potential against polyethylene-like polymers. Our findings suggest that this field of study is still in the early stages of development. Moreover, considering the diverse ecological niches associated with Streptomyces, these actinobacteria could serve as complementary agents for plastic waste management and thereby enhance carbon cycle dynamics.

10.
Rev. Nutr. (Online) ; 34: e200297, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1351560

RESUMO

ABSTRACT Objective Iron deficiency and vitamin A deficiency are two of the main micronutrient deficiencies. Both micronutrients are essential for human life and children's development. This study aimed to investigate the effects of vitamin A deficiency on ferritin and transferrin receptors' expression and its relationship with iron deficiency. Methods Five diets with different vitamin A-to-iron ratios were given to thirty five 21-day-old male Wistar rats (separated in groups of seven animals each). The animals received the diet for six weeks before being euthanized. Serum iron and retinol levels were measured as biochemical parameters. Their duodenums, spleens, and livers were analyzed for the expression of ferritin and transferrin receptors by Western Blotting. Results Regarding biochemical parameters, the results show that when both vitamin A and iron are insufficient, the serum iron content (74.74µg/dL) is significantly lower than the control group (255.86µg/dL). The results also show that vitamin A deficiency does not influence the expression of the transferrin receptor, but only of the ferritin one. Conclusion Vitamin A deficiency regulates the expression of ferritin in young male Wistar rats.


RESUMO Objetivo A deficiência de ferro e de vitamina A são duas das principais deficiências de micronutrientes, sendo que ambos são essenciais para a vida humana e o desenvolvimento das crianças. O objetivo deste estudo foi investigar o efeito da deficiência de vitamina A na expressão de ferritina e o receptor de transferrina e sua relação com a deficiência de ferro. Métodos Cinco dietas com diferentes proporções de vitamina A para ferro foram administradas a 35 ratos Wistar machos de 21 dias de vida (sete animais por grupo). Os animais receberam a dieta por seis semanas antes de serem eutanasiados. Os níveis séricos de ferro e retinol foram medidos como parâmetros bioquímicos. Duodeno, baço e fígado foram analisados quanto à expressão de ferritina e o receptor de transferrina por Western Blotting. Resultados Em relação aos parâmetros bioquímicos, os resultados mostram que quando a vitamina A e o ferro são insuficientes, o teor de ferro sérico (74.74µg/dL) é significativamente menor do que no grupo controle (255.86µg/dL). Os resultados também mostram que a deficiência de vitamina A não influencia a expressão do receptor da transferrina, mas da ferritina. Conclusão A deficiência de vitamina A regula a expressão de ferritina em ratos Wistar machos jovens.


Assuntos
Animais , Cobaias , Ratos , Deficiência de Vitamina A , Receptores da Transferrina , Ferritinas , Ratos Wistar , Dieta
11.
Artigo em Inglês | LILACS, COLNAL | ID: biblio-989575

RESUMO

ABSTRACT Introduction: Topiramate is a drug used to treat various types of epilepsy and as prophylaxis in cases of migrainous headache. One of its mechanisms of action is the inhibition of carbonic anhydrase in the kidney that triggers the excretion of alkaline urine resulting in metabolic acidosis. Case presentation: 17-year-old female patient from Mexico City who regularly uses topiramate, quetiapine and sertraline for the management of depressive disorder. She developed normal anion gap metabolic acidosis secondary to topiramate intake. As a result, she required invasive ventilatory support due to reduced consciousness and respiratory distress. Adequate response to management with laxatives and bicarbonate was achieved, with full renal and neurological recovery. Discussion: Metabolic acidosis is the most common acid-base disorder observed in clinical practice. The difference between measurable cations and anions, known as anion gap, helps to classify the severity of acidosis. Bicarbonate losses or renal tubular disorders generate normal anion gap acidosis as opposed to acidosis resulting from an overproduction of endogenous acid or renal failure, which causes high anion gap. Topiramate is a little known cause of normal anion gap metabolic acidosis; by inhibiting carbonic anhydrase, it causes mixed renal tubular acidosis or type 3 acidosis, as a consequence of the inability to secrete hydrogen ions in the collecting tubule, and a limitation of bicarbonate reabsorption in the proximal tubule. Conclusion: Topiramate, either in therapeutic doses or in overdose, can lead to normal anion gap metabolic acidosis due to the inhibition of carbonic anhydrase in the kidneys. It is usually reversible after starting bicarbonate.


RESUMEN Introducción. El topiramato es un medicamento que se usa en el tratamiento de varios tipos de epilepsia y como profilaxis en casos de cefalea migrañosa. Entre sus mecanismos de acción, la inhibición de la anhidrasa carbónica en el riñón desencadena la excreción de orina alcalina ocasionando acidosis metabólica. Presentación del caso. Paciente femenino de 17 años procedente de la Ciudad de México con antecedente de consumo de topiramato, quetiapina y sertralina para manejo de síndrome depresivo, quien desarrolla acidosis metabólica de anión restante normal secundaria a ingesta de topiramato. La joven requiere soporte ventilatorio invasivo por deterioro del estado de conciencia y síndrome de dificultad respiratoria y presenta adecuada respuesta a manejo con catártico y bicarbonato sin compromiso renal y sin secuelas neurológicas. Discusión. La acidosis metabólica es la alteración ácido base más frecuente en la práctica clínica. La diferencia entre cationes y aniones medibles, conocida como anión restante o brecha aniónica, permite clasificar este tipo de acidosis. Las pérdidas de bicarbonato o trastornos de la función tubular renal generan acidosis de anión restante normal; por el contrario, la acidosis causada por sobreproducción de ácido endógeno o por insuficiencia renal genera anión restante elevado. El topiramato es una causa poco conocida de acidosis metabólica con anión restante normal; al inhibir la anhidrasa carbónica, se ocasiona una acidosis tubular renal mixta o tipo 3 debido a una in capacidad de secreción de hidrogeniones en el túbulo colector y una limitación en la reabsorción del bicarbonato en el túbulo proximal. Conclusión. El topiramato en dosis terapéutica o en sobredosis puede generar acidosis metabólica de anión restante normal debido a la inhibición de la anhidrasa carbónica a nivel renal. Se trata de un cuadro reversible en el cual el manejo con bicarbonato ha mostrado buenos resultados clínicos.


Assuntos
Humanos , Acidose Tubular Renal , Intoxicação , Anticonvulsivantes
12.
NOVA publ. cient ; 15(28): 19-31, jul.-dic. 2017. tab, graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-895079

RESUMO

Resumen En la actualidad la astaxantina de origen natural es uno de los pigmentos carotenoides con importantes aplicaciones en la industria alimenticia, farmacéutica y cosmética, debido a sus grandes propiedades dentro de las que se destaca su gran poder antioxidante, efecto preventivo del cáncer, incremento de la respuesta inmune, inhibición de los radicales libres entre muchas otras. Haematococcus pluvialis es una microalga verde de agua dulce y es una de las fuentes naturales con mayor producción de astaxantina ya que es capaz de acumular hasta un 3% de astaxantina en peso seco. El objetivo del presente trabajo fue determinar el medio de cultivo y las condiciones óptimas para el crecimiento y la producción de astaxantina a partir de Haematococcus pluvialis. La influencia de diferentes factores como el pH, temperatura, agitación, aireación CO2 e iluminación favorecen el crecimiento celular, al darle un ambiente óptimo a la microalga. Para determinar las condiciones nutricionales óptimas, se evaluó el efecto de diferentes medios de cultivo (BBM, OHM, RM) en Birreactores de 500mL con 350mL de medio y 1x104cel/ml de inóculo en fase exponencial, las condiciones de cultivo empleadas fueron: pH. 6.7 a 7, CO2 al 5%, fotoperiodo de 16 horas luz 8 oscuridad, irradianza 70μE/m2s; Los resultados mostraron que el mayor crecimiento o producción celular se obtuvo en el medio RM con 7,5 x 105 cel/ml en el día 36, y la mayor producción de astaxantina se obtuvo en el medio RM con una concentración de 8.3 μg/ml en el tratamiento 4.


Abstract Currently astaxanthin of natural origin is one of the carotenoids with important applications in the food, pharmaceutical and cosmetics, due to their large properties within its powerful antioxidant, cancer preventive effect, increase the immune response, inhibiting free radicals among many others. Haematococcus pluvialis is a freshwater green microalgae and is one of the largest natural sources of astaxanthin production as it is able to accumulate up to 3% astaxanthin by dry weight. The aim of this study was to determine the culture medium and the optimal conditions for growth and production of astaxanthin from Haematococcus pluvialis. The influence of different factors such as pH, temperature, agitation, aeration and lighting, CO2, promote cell growth, by giving an optimal environment to microalgae. To determine the optimal nutritional conditions for cell growth the effect of different culture media (BBM, OHM, RM) in bioreactors of 500 ml with 350mL of medium and 1x104 cells/ml inoculum was evaluated in exponential phase, the culture conditions employed they were: pH. 6.7 to 7, 5% CO2, 16 hours photoperiod Light 8 dark, irradiance 70 μE / m2s; The results showed that the highest growth and cell reproduction was obtained in the middle RM with 7.5 x 105 cells /ml on day 36, and increased production of astaxanthin was obtained in the middle RM with a concentration of 8.3 ug / ml in the treatment 4.


Assuntos
Humanos , Microalgas , Indústria Alimentícia , Meios de Cultura , Crescimento Celular
13.
Biotechnol Lett ; 35(10): 1571-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23801114

RESUMO

The synthesis of monodispersed magnetic silica nanoparticles (MSN) is described using a water-in-oil reverse microemulsion system that does not require the use of co-surfactants. Sodium silicate, Tween 20 as a neutral surfactant and 1-butanol as the organic phase were used. There are several advantages of the proposed method including a saturation magnetization value of 10 emu/g for the particles obtained, uniformity of size and that they are easily functionalized to bind urease covalently. Moreover, the intra-day, inter-day and long-term stability results confirm that the procedure was successful and the enzyme-linked MSNs were stable over repeated uses and storage retaining more than 75% activity after 4 months.


Assuntos
Emulsões , Enzimas Imobilizadas/metabolismo , Magnetismo , Nanopartículas , Dióxido de Silício , Urease/metabolismo , Biotecnologia/métodos , Estabilidade Enzimática , Enzimas Imobilizadas/química , Urease/química
14.
J Mater Chem B ; 1(45): 6283-6290, 2013 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32261701

RESUMO

Silica-collagen scaffolds were obtained by covalent binding of an aminosilane to glutaraldehyde fixed collagen hydrogels, rendering a three dimensional network of silicon coated collagen fibrils. When compared to non-silicified collagen, silica containing matrices exhibited a 60 fold increment in the rheological properties. Moreover, acellular degradation by collagenase type I indicated that enzymatic digestion occurred at a slower rate for silica modified hydrogels, hence enabling a controlled degradation of the obtained material. In addition, fibroblastic cells seeded on silicified collagen matrices were able to adhere, proliferate and migrate within the scaffold for over 3 weeks as shown by MTT tests and hematoxylin-eosin staining. These results suggest that the herein described method could be useful in the design of materials for tissue engineering purposes.

15.
Recent Pat Biotechnol ; 5(1): 54-61, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21517744

RESUMO

Drug delivery systems are designed to improve therapy efficacy as well as patient compliance. This could be accomplished by specifically targeting a medication intact to its active site, therefore reducing side-effects and enabling high local drug concentrations. Silica nanoparticles have gained ground in the biomedical field for their biocompatibility and biodegradability, being themselves inert and stable, thus enabling a variety of formulation designs for application in the pharmaceutical industry. This paper is a review of the recent patents on the applications of silica nanoparticles for drug delivery and their preparation. The review will focus on the different techniques available to obtain silica nanoparticles with variable morphology and their drug targeting applications, providing an overview of silica particles synthesis described in the literature.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Patentes como Assunto , Dióxido de Silício/química , Emulsões/química , Humanos , Magnetismo , Preparações Farmacêuticas/química
16.
Biomédica (Bogotá) ; 26(4): 509-516, dic. 2006. tab, graf
Artigo em Espanhol | LILACS | ID: lil-475404

RESUMO

Introducción. La enfermedad trofoblástica gestacional comprende un conjunto de patologías caracterizadas por crecimiento e invasión anómalos del trofoblasto. Las bases moleculares de esta patología son desconocidas, en parte por la dificultad para disponer de modelos biológicos adecuados. Se plantea que el sistema de factores de crecimiento similares a la insulina puede tener un papel fundamental en el desarrollo de la enfermedad. Objetivo. Caracterizar cultivos primarios de placentas de primer trimestre provenientes de pacientes con mola hidatidiforme completa y aborto espontáneo no molar mediante morfología, inmunocitoquímica y expresión diferencial de algunos genes del sistema de factores de crecimiento similares a la insulina. Materiales y métodos. Se empleó inmunocitoquímica para determinar células trofoblásticas y detección por transcripción reversa y reacción en cadena de la polimerasa de genes del sistema de factores de crecimiento similares a la insulina asociados al tipo celular. Resultados. La morfología evidenció heterogeneidad de los cultivos, incluidas células mesenquimales, trofoblásticas y de decidua. El contenido de células de trofoblasto con citoqueratina-7 (marcador específico) estuvo entre 16 y 37 por ciento. La expresión de genes corroboró la presencia de trofoblasto por medio del ARNm del factor II de crecimiento similar a la insulina, en tanto que los transcritos de la hormona de crecimiento variante evidenciaron la presencia de sincitiotrofoblasto. El factor I de crecimiento similar a la insulina y la proteína de unión tipo 1 se relacionaron con células mesenquimales y de decidua. Se observó una mayor expresión del factor II de crecimiento similar a la insulina en tejidos molares en comparación con aborto no molar. Conclusiones. Los resultados mostraron la utilidad de combinar tres metodologías, morfología, inmunocitoquímica y expresión de genes, como herramientas para la caracterización y seguimiento de cultivos placentarios a partir....


Introduction. Gestational trophoblastic disease includes a group of pathologies characterized by abnormal trophoblast growth and invasion. The molecular bases of the disease are largely unknown, due in part to the lack of appropriate biological models. The insulin-like growth factor (IGF) system plays a fundamental role in the growth and development of many tissues and is involved in the progression of several diseases. Objectives. Primary cell cultures derived from first trimester placenta were characterized from patients with complete hydatidiform mole and spontaneous non molar abortion by immunocytochemical and molecular methods. Materials and Methods. The immunocytochemical method used specific markers for trophoblastic cells, whereas RT-PCR was used to identify insulin-like growth factor gene expression. Results. Histochemical staining with hematoxilin-eosin revealed that the cultures contained heterogeneous cell types, including trophoblast and endometrial decidual cells. The ratio of trophoblast cells in the cultures varied between 16% and 37%, as detected by cytokeratine-7 as the specific trophoblast marker. Gene expression analysis corroborated the presence of trophoblasts by detecting insulin-like growth factor II mRNA, whereas GH-V transcripts were correlated with the presence of syncitiotrophoblasts. Insulin-like growth factor I and insulin-like growth factor binding protein 1 mRNAs were related to mesenchyimal and decidual cells, respectively. Higher insulin-like growth factor II expression levels were found in molar tissues in comparison with non-molar abortions. Conclusion. By combining three methodologies—morphology, immunocytochemistry and gene expression, characterization and follow-up of placenta cultures from abnormal tissues is found to facilitate diagnosis.


Assuntos
Técnicas de Cultura de Células , Mola Hidatiforme Invasiva , Placenta/patologia , Somatomedinas
17.
Biomedica ; 26(4): 509-16, 2006 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-17315477

RESUMO

INTRODUCTION: Gestational trophoblastic disease includes a group of pathologies characterized by abnormal trophoblast growth and invasion. The molecular bases of the disease are largely unknown, due in part to the lack of appropriate biological models. The insulin-like growth factor (IGF) system plays a fundamental role in the growth and development of many tissues and is involved in the progression of several diseases. OBJECTIVES: Primary cell cultures derived from first trimester placenta were characterized from patients with complete hydatidiform mole and spontaneous non molar abortion by immunocytochemical and molecular methods. MATERIALS AND METHODS: The immunocytochemical method used specific markers for trophoblastic cells, whereas RT-PCR was used to identify insulin-like growth factor gene expression. RESULTS: Histochemical staining with hematoxilin-eosin revealed that the cultures contained heterogeneous cell types, including trophoblast and endometrial decidual cells. The ratio of trophoblast cells in the cultures varied between 16% and 37%, as detected by cytokeratine-7 as the specific trophoblast marker. Gene expression analysis corroborated the presence of trophoblasts by detecting insulin-like growth factor II mRNA, whereas GH-V transcripts were correlated with the presence of syncitiotrophoblasts. Insulin-like growth factor I and insulin-like growth factor binding protein 1 mRNAs were related to mesenchyimal and decidual cells, respectively. Higher insulin-like growth factor II expression levels were found in molar tissues in comparison with non-molar abortions. CONCLUSION: By combining three methodologies-morphology, immunocytochemistry and gene expression, characterization and follow-up of placenta cultures from abnormal tissues is found to facilitate diagnosis.


Assuntos
Mola Hidatiforme/patologia , Biologia Molecular , Feminino , Humanos , Imuno-Histoquímica , Reação em Cadeia da Polimerase , Gravidez , Células Tumorais Cultivadas
18.
Biomédica (Bogotá) ; 21(2): 142-149, jun. 2001. tab, graf
Artigo em Espanhol | LILACS | ID: lil-315771

RESUMO

Se describe la estrategia empleada para clonar, en un vector de expresión, un fragmento de 306 pb del gen de STAT5b de rata, amplificado por la técnica de RT-PCR. Se amplificó una región en el terminal 3' donde se encuentra la mayor diferencia entre las secuencias del cADN de las isoformas STAT5a y STAT5b de rata. La clonación se logró utilizando el nuevo sistema TOPO-TA recomendado para productos de difícil clonación. El fragmento se subclonó en el vector pBlueScrip II SK y se caracterizó mediante secuenciación y análisis de restricción. La subclonación se realizó con el propósito de poder obtener sondas sentido y antisentido de ARN por transcripción in vitro. Esta sonda específica se empleó para cuantificar niveles de mARN de STAT5b en hígado de ratas macho mediante la técnica de hibridización en solución o ensayo de proteción de ARNasas


Assuntos
Ratos , Hibridização Genética , Técnicas In Vitro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica
19.
Bol. méd. postgrado ; 12(1): 42-52, ene.-mar. 1996.
Artigo em Espanhol | LILACS | ID: lil-193610

RESUMO

Se estudio el perfil de unión de [3H]-Benzilato de Quinuclidinilo ([3H]-QNB) al receptor colinérgico muscarínico (RCM) de corteza frontal (CFH) e hipocampo humano (HPH) en presencia de diferentes buffers. Cuando las fracciones de CFH se prepararon y ensayaron en Buffers TRIS, FOSFATO o HEPES, la unión fue compatible con una discreta cooperatividad homotrópica positiva (coeficiente de Hill: 1.10-1.37). Cuando los ensayos de unión de [3H]-QNB al RCM de CFH se realizaron con buffers imidazol o citrato, la cinética resultó hiperbólica simple. El fenómeno de cooperatividad positiva se encontró en HPH mediante el uso de buffer fosfato, pero no con iris e imidazole. El uso de borato como buffer para preparar y ensayar las fracciones de CFH o HPH indujo una cinética compatible con cooperatividad homotrópica negativa o heterogeneidad, con 32-36 por ciento de sitios de alta afinidad y 64-68 por ciento de baja afinidad. El efecto inhibitorio de la fuerza iónica sobre la unión de [3H]-QNB fue similar en borato, imidazol, tris, herpes y citrato. A altas concentraciones, el efecto del buffer fosfato fue también inhibitorio, sin embargo, a bajas concentraciones, se observó un 10 por ciento de aumento en la unión. Estos resultados sugieren que la unión de [3H]-QNB al RCM humano es compleja y dependiente de las condiciones del medio.


Assuntos
Humanos , Masculino , Feminino , Colinérgicos/análise , Receptores Colinérgicos/análise , Receptores Colinérgicos/antagonistas & inibidores , Hipocampo/anatomia & histologia , Córtex Pré-Frontal/anatomia & histologia
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