Medicina molecular y genética

Los sistemas de administración de fármacos con tecnología de liberación controlada han surgido como una herramienta poderosa para el tratamiento de diversas enfermedades. El índice terapéutico del agente activo se puede mejorar aumentando su estabilidad, solubilidad y biodisponibilidad, junto con la administración en un sitio específico. Los polímeros han desempeñado un papel integral como portadores en la formulación de un sistema de administración de fármacos eficiente por su estabilidad, capacidad de carga del fármaco y propiedades ajustables. El 'quitosano', el polímero catiónico natural derivado de la quitina, ha recibido una atención creciente principalmente debido a su capacidad de biodegradabilidad, biocompatible, no tóxico, mucoadhesivo y capacidad para dirigirse a propiedades de administración específicas. El quitosano tiene muchas propiedades medicinales, como antimicrobiano, antioxidante, baja inmunogenicidad, etc., que mejoran su potencial en diferentes aplicaciones biomédicas. En esta revisión se analizan las diversas técnicas para la preparación de micro/nanopartículas de quitosano. Se examinan varios tipos de sistemas de administración de fármacos basados ??en quitosano para dilucidar su papel en diferentes aplicaciones biomédicas.

La sostenibilidad ambiental y el uso de biomateriales ambientalmente aceptables son áreas importantes de investigación científica e industrial. En los últimos tiempos, la identificación y aplicación de biopolímeros adecuados en lugar de los polímeros convencionales derivados del petróleo están ganando más atención. Las nanopartículas y nanocompuestos de quitosano y derivados del quitosano son muy prometedores debido a sus propiedades versátiles y han encontrado aplicaciones en diversas áreas como la biomédica, los alimentos, el envasado de alimentos y el cuidado personal. Muchos estudios sugieren que las nanopartículas de quitosano y sus derivados son uno de los mejores materiales de barrera y recubrimiento de película para preservar la calidad de los alimentos y para proporcionar productos para el cuidado de la piel, principalmente debido a su biodegradabilidad y propiedades antimicrobianas. La presente revisión brinda información sobre el progreso logrado en la aplicación de nanopartículas de quitosano específicamente en alimentos y envases de alimentos, productos de cuidado personal y en la industria biomédica. Los estudios futuros abordarán el establecimiento de una ampliación industrial de las nanopartículas de quitosano, la seguridad y los aspectos de calidad de estos productos derivados del quitosano para uso humano.

Se evaluaron los efectos de cuatro factores variables como proteína, sorbitol, montmorillonita (MMT) y quitosano sobre las propiedades de películas de gelatina de piel de bagre y tiburón multicompuestos con base en la Metodología de Superficie de Respuesta (MSR). La incorporación de quitosano tuvo un efecto positivo sobre la resistencia a la tracción, el Módulo de Young y la tasa de transmisión de vapor de agua (p<0,05). Por otro lado, el quitosano y el MMT habían disminuido el alargamiento de las películas (p<0,05). La transparencia de la película de gelatina aumentó con la adición de gelatina y quitosano, mientras que disminuyó con la adición de MMT. A partir del presente estudio, se puede concluir que se podrían lograr películas de gelatina con buenas propiedades mecánicas y de barrera con 4,50% de gelatina, 25% de sorbitol, 0,37% de MMT y 3,25% de quitosano. De este modo, se podrían formular películas de gelatina multicompuestas con cualquier propiedad deseada basándose en los resultados de la metodología de superficie de respuesta y estas películas serían adecuadas para películas o recubrimientos comestibles para pescado y otros productos alimenticios en las industrias de procesamiento de alimentos.

Antecedentes: El proceso de tratamiento para la eliminación de metales pesados ??y colorantes es un factor preocupante en la salud ambiental porque puede contribuir a la formación de nuevos contaminantes.

Objetivos: Obtener y utilizar quitosano de Zygomycetes para el proceso de remoción de metales pesados ??(cadmio) y colorantes azoicos (Negro Reactivo y Rojo Remazol).

Métodos: El quitosano se obtuvo de Rhizopus arrhizus UCP 402 y Mucor javanicus UCP 69 siguiendo el método descrito por Synowiecki y Al-Khateeb (1997) y se sometió a pruebas de remoción durante 18 h, con diferentes concentraciones de Cadmio (0,5-4 mM), Reactive Black (B) y Remazol Red (1-1000 mg/L) en un agitador orbital a 150 rpm a 28°C. Luego, las muestras se sometieron a espectrofotometría y el quitosano expuesto a los contaminantes se sometió a análisis de microscopía electrónica.

Resultados: La eficiencia de remoción de cadmio por el quitosano de Rhizopus arrhizus mostró datos de 92% (0,5 mM), 92,8% (1 mM), 75,9% (2 mM), 54% (3 mM) y 54,5% (4 mM) a pH 6,0. La eficiencia de remoción de colorantes por el quitosano de Mucor javanicus fue de aproximadamente 100% (1 mg/L), 100% (10 mg/L), 100% (50 mg/L), 98% (100 mg/L), 55% (1000 mg/L) para Reactive Black (B) y 100% (1 mg/L), 100% (10 mg/L), 100% (50 mg/L), 98% (100 mg/L), 59% (1000 mg/L) para Remazol Red.

Conclusión: El quitosano obtenido por las cepas fue capaz de remover el cadmio y los colorantes reactivos: Negro Reactivo (B) y Rojo Remazol en todas las condiciones probadas.

El objetivo del presente estudio fue investigar los efectos a largo plazo del gel de quitosano-fosfato de glicerol (quitosano-GP) en el entorno articular tras la implantación en defectos osteocondrales experimentales en caballos. Los animales fueron sometidos a una artroscopia experimental de ambas articulaciones tibiotarsianas para la creación de defectos osteocondrales en el aspecto medial de la cresta troclear lateral. Se seleccionó al azar una extremidad trasera para el tratamiento con gel de quitosano-GP, mientras que la extremidad trasera contralateral sirvió como control sin tratamiento. Se realizó un seguimiento de los caballos en diferentes puntos temporales durante 24 meses, mediante análisis clínicos, radiográficos, ultrasonográficos y de líquido sinovial. Se produjo un agrandamiento de todas las articulaciones operadas en ambas extremidades traseras durante los primeros 30 días. No se observaron signos radiográficos de osteoartritis, en las articulaciones tratadas o no tratadas. La ecografía reveló un tejido de relleno de defectos similares y líquido sinovial con características similares en las articulaciones de control tratadas o no tratadas, con áreas de defectos osteocondrales que disminuyeron progresivamente. El análisis del líquido sinovial no ha mostrado diferencias en las concentraciones de proteína total, prostaglandina E2, sulfato de condroitina y ácido hialurónico, ni en el recuento de glóbulos blancos, al comparar las articulaciones tratadas con las no tratadas. En conclusión, el quitosano-GP es biocompatible con el entorno articular equino y no provocó efectos clínicos relevantes, respuesta inflamatoria o efectos tóxicos en las articulaciones de los caballos.

Cada vez se detectan más productos farmacéuticos en el medio ambiente. Sin embargo, los sistemas de tratamiento convencionales no proporcionan un tratamiento adecuado para la eliminación de fármacos y aún no existe un estándar regulado para su limitación en el agua. La adsorción es una de las técnicas más efectivas y prácticas para eliminar contaminantes del agua. Hoy en día, se presta mucha atención al desarrollo de desechos naturales para utilizarlos como adsorbentes en plantas de tratamiento de aguas residuales. Entre los materiales de estudio biológico, el quitosano tiene muchas aplicaciones en varios campos en función de sus propiedades químicas y físicas, además de ser abundante y económico. El quitosano tiene capacidades de eliminación de ciertos contaminantes del agua, como colorantes, iones metálicos, fenol y diferentes aniones. Además, se utiliza ampliamente como portador de componentes farmacéuticos en la administración de fármacos. Basándose en las propiedades y aplicaciones que ya se conocen del quitosano, su uso para eliminar productos farmacéuticos podría resolver las técnicas costosas e ineficientes que se emplean actualmente en los tratamientos de aguas residuales. En este artículo se ha analizado el potencial del quitosano y sus derivados para la eliminación de productos farmacéuticos.

Peroxides are an interesting group among biological active natural compounds. These metabolites contain a peroxide group (-O-O-) in which each oxygen atom is bonded to the other oxygen and to another atom. β-Oxygen in hydroperoxide group is considered as more active. Present review describes research on more than 230 natural peroxides isolated from plants, algae, and fungi. Intensive searches for new classes of biologically active metabolites produced by terrestrial and marine origin have resulted in the discovery of dozens of compounds possessing high antimalarial, antibacterial, cytotoxic, and other pharmacological activities as an important source of leads for drug discovery.

The understanding of genetic factors involved in the risk for obesity has identified genes that are closely linked to obesity related diseases. A single gene effect versus multiple genes effect may indicate either the interaction unique to various environments that regulate abnormal molecular or cellular events responsible for obesity with several hypotheses proposed in relation to the development of obesity. The understanding of the development of adipogenesis has been the focus of the global community with obesity genetics, epigenetic regulatory mechanisms and transcription factors important to the world-wide obesity epidemic with increased risk for adiposity. The search for specific genes that are sensitive to nutritional regulation, oxidative stress, inflammation, endocrine disease, lipid/ glucose metabolism, insulin resistance and Alzheimer’s disease has been the focus of the current obesity epidemic in various developed countries. Epigenetics is now considered as an important mechanism for the development of obesity and can result from changes in cellular chromatin structure without alterations in DNA sequence, including DNA methylation, histone modifications and chromatin remodelling. Epigenetic modifications induced by unhealthy diets and the environment effect nuclear/mitochondria interactions and implicate nuclear receptors such as Sirt 1 as a single gene effect with interactions with microRNA and transcription factors such as p53 that regulate cellular and immune events with effects on cellular lipid metabolism and energy expenditure that induce senescence with poor DNA repair. Epigenetic modifications in various communities are now closely involved in NAFLD associated with excess transfer of fat to the adipose tissue and the induction of obesity in developed countries. The failure of various anti-obese drugs has encouraged the use of nutrigenomic diets that reverse senescence and assist in the early nutritional intervention that reverses NAFLD with reduced adiposity.

Background: Therapies for muscular dystrophies remain a major challenge in spite of advanced strategies using either cell or gene therapy. We here propose a combined approach of cell and gene therapy. As gene delivery vehicles with specific homing potential we have chosen mesoangioblasts which are stem cells with mesodermal potential. This study specifically tests the maintenance of myogenic properties by EGFP-transduced mesoangioblasts and their ability to function as retroviral packaging cells in transient culture.

Methods: Mesoangioblasts transduced to express EGFP (EGFP-MA) were tested for myogenic properties in coculture. Survival and in situ myogenic differentiation were studied upon injection into degenerating M. gastrocnemius of athymic mice. In situ participation in muscle regeneration was confirmed on cryo-sections using EGFP fluorescence as marker. The ability of mesoangioblasts to serve as retroviral packaging cells was tested using the murine cell line NIH 3T3 fibroblasts as recipients in vitro and evaluation of transduction by fluorescence microscopy.

Results: EGFP-MA retained the ability to differentiate into skeletal muscle myotubes upon co-culture with C2C12 cells. In vivo, mouse M. gastrocnemius exhibited EGFP-signals within and at the basal lamina of skeletal muscle fibers 3, 10 and 24 days after injection of EGFP-MA. In culture, target cells could be transduced with EGFPencoding virions produced by mesoangioblasts.

Conclusions: Introduction of a retroviral vector into mesoangioblasts did not interfere with the myogenic properties of mesoangioblasts in culture or in vivo. Mesoangioblasts are able to function as retroviral packaging cells in vitro. While a possible therapeutic application of this new gene delivery system will require further detailed analysis of the long-term efficiency and the quantitative aspects of the method, our proof of principle study shows that the approach is feasible.

The concept of therapeutic and diagnostic activities is mainly concerned to medical and pharmaceutical sciences. However, the recent trends earmarked the synergistic approaches of science and technology to provide more vibrant and effective medical treatment for the solution of health complications in medical sciences and it’s the genesis of modern medical diagnostic. Hence, medical research is directed towards most promising and challenging fields of therapeutics + diagnostics = theranostics. The feasibility of theranostics nowadays is apprehended in various disease diagnostics and curing processes. The modern medical diagnostic techniques are based on molecular imaging where each technique has its own characteristics, merits and demerits and most of the imaging modalities are complementary to each other. To provide better results of imaging the theranostic agents play very important role. The useful biopolymer research has been assisted towards the evolution of improved imaging agents in the form of quantum dots, nanoparticles and other new regenerative medication. The mini review focuses on theranostic development with special emphasis on quantum dots, and nanoparticles in the light of biopolymer, chitosan for cancer diseases.

Down syndrome (DS) is a complex disorder characterized by well-defined and distinctive phenotypic features. Different karyotypes are associated with varying phenotypic expression of DS. The type of karyotypes in the children with DS plays an important role in genetic diagnosis and family counselling. This study describes the characteristics of karyotypes leading to phenotypic Down syndrome in 1213 cases diagnosed between 1992 and 2009 in South Region of Turkey. The frequency of occurrence of the different karyotypes was analyzed. The karyotype results were normal in 9.1% of all cases. However, chromosomal abnormalities (CAs) were detected in nearly 91% of all cases. The free trisomy 21 was the most common karyotype (nearly 93% of all cases). The ration of mosaic trisomy 21 was 2.5%. The CAs in addition to trisomy 21 was present in 1.5% of cases. The ratio of Robertsonian and reciprocal translocations in these variants were 2.3% and 0.3%, respectively. The ration of other variants was nearly 1%. This study showing the frequency and distribution of karyotypes causing DS, are the great value to be gleaned from studies of DS patients in furthering our understanding of the atypical clinical features associated with DS. These cytogenetic investigations carried out greatly helped in the management of these children and for counseling the affected families.

Inherited thrombophilia has recently been identified as a major cause of thrombembolism, but it may also contribute to adverse pregnancy outcomes and recurrent pregnancy loss. Three gene mutations namely leiden (FV G1691A), prothrombin (FII G20210A), and methylenetetrahydrofolate reductase (MTHFR C677T) are the most common types of hereditary thrombophilias in women with RPL, which in turn can result in placentation. These are usually undiagnosed, because most carriers are asymptomatic. The aim of this study was to determine the association of specific inherited thrombophilias and recurrent pregnant loss (RPL) among Saudi women. The study included 142 females were 72 had a history of 2 or more events of fetal loss in any of the 3 trimesters of pregnancy. The remaining 70 were clinically healthy women with a good obstetric history and have designated as a control group. Detection of inherited thrombophilia genes mutations was confirmed using different PCR screening protocols. The frequencies of FV & FII mutations related to the pregnancy loss stages showed that FV mutation ratio was similar among cases with early or late stage pregnancy loss (25% - 26%) but significantly higher than that of controls (1.4%). On the other hand FII mutation ratio was high among cases with late pregnancy loss (50%) followed by early pregnancy loss (38%) and was significant higher than that of controls (1.4%). MTHFR C677T mutation was more common in group of women with fetal loss in first trimester compared to the controls. We have reported that the combinations of two or more thrombophilic polymorphism risk factors were observed in 10.8% healthy Saudi women with unexplained RPL while no more than one risk factor was observed in any of the controls. We concluded that there is a strong association between the combined inherited thrombophilic mutations related to FV G1691A, FII G20210A, and MTHFR C677T genes among Saudi women. Our data confirm the hypothesis that inherited thrombophilia is indeed a significant abnormality in the RPL subjects.

Thalassemia and Sickle Cell Disease (SCD) both are genetic blood disorders occurring by destruction in red blood cells (RBCs). Every year about 300,000 infants worldwide are born with Thalassemia syndrome (30 per cents) and sickle cell anaemia (70 per cents. Globally, the percentage of carriers of Thalassemia is greater than that of carriers of SCA, but because of the high frequency of the sickle cell gene in certain regions the number of affected births is higher than with Thalassemia. Due to a large population, and same blood, marriage in many communities, there is always a high chance of genetic disorders in Chhattisgarh which is one of the growing states of India. The incidence of genetic blood diseases in Chhattisgarh is considered high. According to the screened population, it is observed that the prevalence of SCD was 2.1%, sickle cell trait was 10% among different tribes. Also Thalassemia gene is prevalent in different Here we are describing the challenges, including lack of knowledge about genetic disease and less facility faced by parents in the Chhattisgarh his children affected by Thalassemia and SCD. We use Hardy-Weinberg equilibrium (HWE), a genetic approach for the prediction of allelic frequencies of SCD and Thalassemia. The aim of this study is to generate carrier frequencies of both the disease using HWE and accepting a number of resources which are useful for the eradication of SCD and Thalassemia from the affected population group.

Autism spectrum disorders (ASD) is a complex heterogeneous neuro-developmental disorders with varying degrees of severity that can cause significant social, communication and behavioral challenges. ASD research has received considerable attention and continues to be focused because of limited options available for its successful management. The detail understanding of the ASD etiology has now been progressed to encompass genetic, epigenetic, neurological, hormonal, and environmental factors that may affect the individual symptoms of the patients with ASD. The diagnosis of ASD is not that easy since there is no clinical test, such as blood test, available for diagnosis. Specific set of genetic and epigenetic biomarkers represented by a characterized phenotype can respond efficiently to the treatment with a specific drug or intervention. Nevertheless, children and young people with ASD have higher chances of developing unbearable side effects from the use of medications. The general etiology (genetic and epigenetic) and associated symptoms, biomarkers and treatment options of autism are briefly discussed in this article.

We describe a third case with clinical characterization due to 7p22.1 microduplication in an 8 year old female diagnosed concurrently with autoimmune Systemic Lupus Erythematosus. We propose that 7p22.1 microduplication can be associated with autoimmune arthritis as consequent copy number variations in autoimmune gene susceptibility loci within chromosome 7. Our case highlights the need for joint surveillance in children with microduplication syndromes and further contributes towards 7p22 duplication being a recognizable dysmorphic syndrome.

Chronic heart failure (CHF) remains a leading cause of cardiovascular morbidity and mortality worldwide that is characterized pandemic features. Metabolic diseases, neurohumoral state, and systemic inflammatory response are considered the origin of microvascular endothelial cell inflammation that leads to development of CHF and supporting cardiac remodelling and vascular dysfunction. Endothelial-derived microparticles (EMPs) are considered a novel biological marker of endothelial injury and vascular tone disorders. Biological effect of EMPs realizes through supporting of cell-to-cell cross-talking mediated by transport microRNA, active molecules, hormones, peptides, regulator proteins, etc. EMPs derived from activated endothelial cells may play a pivotal role in the vascular remodelling and endothelial reparation. In opposite, EMPs originated from apoptotic endothelial cells are considered a direct trigger of vascular injury. The review is addressed to discussion of one of possible mechanism of effect realizing of endothelial-derived microparticles different origin in heart failure affected endogenous reparation and tissue injury.

Antecedentes: La metilación de MGMT, junto con la codeleción de 1p/19q y la mutación de IDH1, es un biomarcador importante en los gliomas de alto grado. La metilación de MGMT indica una mejor respuesta a la quimioterapia con temozolomida; los pacientes con oligodendrogliomas anaplásicos con codeleción de 1p/19q se benefician preferentemente de la quimioterapia adyuvante. La pirosecuenciación es un método que permite medir el nivel de metilación de MGMT de manera cuantitativa.
Objetivo: Comparar el nivel medio de metilación del promotor de MGMT de los gliomas de alto grado y correlacionarlo con otros parámetros y marcadores clínicos, incluida la codeleción de 1p/19q y la mutación de IDH1 o IDH2.
Métodos: Se utilizó pirosecuenciación para detectar cuantitativamente el nivel de metilación del promotor MGMT para 171 gliomas de alto grado. También se detectaron mutaciones en los genes IDH1 e IDH2 mediante pirosecuenciación o inmunohistoquímica (n = 166). La detección de la eliminación 1p/19q se realizó mediante hibridación in situ con fluorescencia (n = 46). El análisis estadístico se realizó utilizando R-Stats v2.15.2.
Resultados: Una mayor metilación se correlacionó con un menor grado y mutación en IDH1 o IDH2 (27,0% frente a 16,6% p = 0,008; y 27,5 frente a 16,1 p = 0,002 respectivamente). La codeleción 1p/19q frente a la no codeleción se asocia con un nivel particularmente alto de metilación (42,2% frente a 17,7% p = 0,001). No se observaron diferencias significativas para la edad o el género.
Conclusiones: Los resultados ofrecen una posible explicación del mejor pronóstico observado en pacientes con glioma con codeleción 1p/19q.

Naja naja es una especie de serpiente cobra altamente venenosa de la familia Elapidae y se encuentra común en Asia central. La neurotoxina larga 3 de Naja naja se une a los receptores nicotínicos de acetilcolina en la membrana postsináptica, lo que evita la unión de la acetilcolina y bloquea la excitación de los músculos. Los péptidos antigénicos son biomoléculas complejas que tienen propiedades químicas y físicas únicas que resultan de su composición de aminoácidos. En este estudio, hemos predicho la afinidad de unión de la neurotoxina larga 3 de Naja naja que tiene 71 aminoácidos, lo que muestra 63 nonámeros. Los fragmentos peptídicos de la neurotoxina se pueden utilizar para seleccionar nonámeros para su uso en el diseño de vacunas de péptidos sintéticos y para aumentar la comprensión de las funciones del sistema inmunológico en los estudios de neurotoxinas. Los péptidos antigénicos de la neurotoxina larga 3 de Naja naja son los más adecuados para el desarrollo de vacunas de péptidos sintéticos porque con el segmento pequeño '15-PNGHVCYTKT-24, 26-CDAFCSIRG-34, 36-RVDLGCAATCPTVKTGVDIQCCSTD-60 llamado epítopos antigénicos es suficiente para provocar la respuesta inmune deseada. En esta investigación, predecimos el péptido de unión de clase I y II de MHC porque las moléculas de MHC son proteínas de la superficie celular que participan activamente en la respuesta inmune, la antigenicidad, la accesibilidad a solventes, los residuos polares y no polares que probablemente estén expuestos en la superficie de las proteínas que son potencialmente antigénicas que permiten diseñar una vacuna de péptidos sintéticos.

Diabetes mellitus is a potent metabolic disorder of this time. Due to the progression of disease itself and along with the collateral damages by its various complications this is being considered as one of the greatest threat to patient’s well-being & status. During recent years the prevalence of ulceration in diabetic patients especially foot ulcer has dramatically increased, causing tremendous negative impact over the patient. But unfortunately, there is no reliable animal model that resembles human diabetic foot ulcer, thus the study of ulcer healing under conditions of “diabetes mellitus” remains a challenge. In this literature, we describe a new approach to establish an experimental model that accurately resembles human diabetic foot ulceration. This new model will likely provide a superior way to study diabetic foot ulceration. The objective of this study was aimed to investigate and compare the established “rat models of diabetic foot ulceration” in order to determine the most suitable option that represents the similar state of the disease in human. Diabetic sample were prepared by using Wistar rats and they were divided in to four groups - A. Diabetic foot scalded group, B. bilateral popliteal artery ligation group, C. Diabetic foot scalded plus popliteal artery ligation group, D. Disease control group. After a period of thirty days the rats were assessed by- nail discoloration, degree of muscular atrophy, size of ulcer, purulent secretions and presence granulation tissue in the wound bed. Our study concludes that- “diabetic foot scalded plus popliteal artery ligation group” rats most closely resemble the symptoms of the human diabetic foot.