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The search for materials and process parameters capable of generating hydrogels for soft tissue engineering applications, based on an experimental design strategy that allows the evaluation of several factors involved in their development and performance, has greatly increased. Nevertheless, the fabrication technique can influence their mechanical properties, swelling, crystallinity, and even their susceptibility to contamination by microorganisms, compromising their performance within the tissue or organ. This study aimed to evaluate the influence of the freeze/thaw technique on different characteristics of polyvinyl alcohol-xanthan gum hydrogel. Methods: this research analyzed the critical variables of the freeze/thaw process through a systematic study of a 2 k factorial design of experiments, such as the proportion and concentration of polymers, freezing time and temperature, and freeze/thaw cycles. Additionally, physicochemical analysis, susceptibility to bacterial growth, and cell viability tests were included to approximate its cytotoxicity. The optimized hydrogel consisted of polyvinyl alcohol and xanthan gum at a 95 : 5 ratio, polymer mixture concentration of 15%, and 12 h of freezing with three cycles of freeze/thaw. The hydrogel was crystalline, flexible, and resistant, with tensile strengths ranging from 9 to 87 kPa. The hydrogel was appropriate for developing scaffolds for soft tissue engineering such as the cardiac and skeletal muscle, dermis, thyroid, bladder, and spleen. Also, the hydrogel did not expose an in vitro cytotoxic effect, rendering it a candidate for biomedical applications.

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BACKGROUND: Multiple sclerosis (MS) is a chronic autoimmune inflammatory disease. Low vitamin D levels have been reported to be a risk factor for MS, and genetic variances could be implicated. The aim of this study was to evaluate the association of MS with rs10766197 polymorphism of CYP2R1 gene and rs10877012 polymorphism of CYP27B1 gene. The second aim was to analyse whether these polymorphisms are associated with the severity of the progression of MS. Material and Methods. In a case-control study, we included 116 MS patients and 226 controls, all of whom were Mexican Mestizo. MS was diagnosed by McDonald criteria (2017). A complete neurological evaluation was performed to evaluate the severity of disease progression. Serum 25-hydroxyvitamin D [25(OH) vitamin D] levels were measured by ELISA. Single nucleotide polymorphisms rs10766197 of CYP2R1 gene and rs10877012 SNP of CYP27B1 gene were genotyped by real-time PCR. RESULTS: Serum 25(OH) vitamin D levels were lower in MS patients than in controls (p = 0.009). No differences were observed between serum 25(OH) vitamin D levels of MS patients with severe progression compared to low progression (p = 0.88). A higher frequency of the A allele of CYP2R1 rs10766197 was observed between MS patients and controls (p = 0.05). No differences were observed in the frequency of T allele of CYP27B1 rs10877012 (p = 0.65). In subanalysis, patients with GA + AA genotypes of CYP2R1 rs10766197 had an increased risk of MS compared to controls (p = 0.03). No increased risk was observed in GT + TT genotypes of CYP27B1 rs10877012 (p = 0.63). No differences were observed in allele frequencies of either polymorphism between patients with severe vs. low disease progression. CONCLUSION: Lower serum 25(OH) vitamin D levels were observed in MS patients than in controls, although these levels were not associated with disease progression. Carriers of GA + AA genotypes of CYP2R1 rs10766197 had an increased risk of MS. None of these polymorphisms was associated with severe progression of MS.

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The sterilization processes of nanoparticles (NP) by autoclaving and filtration are two of the most utilized methods in the pharmaceutical industry but are not always a viable option. For this reason, the search for alternative options such as UV and gamma radiation is of interest. In this work, we evaluated both types of sterilization on two types of NP in solid state widely employed in the literature for biomedical applications, poly-(ε-caprolactone) and poly(D, L-lactide-co-glycolide) acid NP stabilized with polyvinyl alcohol. Physicochemical properties and cell viability were studied pre- and post-sterilization. The efficiency of irradiation sterilization was performed by a test of sterility using 1 × 108 CFU/mL of Escherichia coli, Staphylococcus aureus, and Candida albicans. Microbiological monitoring revealed that both methods were sufficient for sterilization. After the UV irradiation sterilization (100 µJ/cm2), no substantial changes were observed in the physicochemical properties of the NP or in the interaction or morphology of human glial cells, though 5 and 10 kGy of gamma irradiation showed slight changes of NP size as well as a decrease in cell viability (from 100 µg/mL of NP). At 5 kGy of radiation doses, the presence of trehalose as cryoprotectant reduces the cell damage with high concentrations of NP, but this did not occur at 10 kGy. Therefore, these methods could be highly effective and low-processing-time options for sterilizing NP for medical purposes. However, we suggest validating each NP system because these generally are of different polymer-composition systems.

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Myotonic dystrophy type 1 is caused by expansion of a CTG trinucleotide repeat situated in the DMPK gene. Worldwide genetic studies suggest a single or limited number of mutational events cause the disease. However, distribution of CTG alleles and disease incidence varies among ethnicities. Due to the great ethnic diversity of the Mexican population, the present study was aimed at analyzing the impact of different lineages in shaping the CTG-repeat allelic distribution in the contemporary Mexican-Mestizo population as well as to shed light on the DM1 ancestral origin. Distribution of CTG-repeat alleles was similar among Mestizo and Amerindian subpopulations with (CTG)11-13 being the most frequent alleles in both groups, which implies that Mexican-Mestizo allelic distribution has been modeled by Amerindian ancestry. We diagnosed a relatively high number of cases, consistent with the high frequency of large-normal alleles found in Mexican subpopulations. Haplotype analysis using various polymorphic-markers in proximity to DMPK gene indicates that a single founder mutation originates myotonic dystrophy type 1 in Mexico; however, Y-STR haplogroups data and the presence of pre-mutated and large normal alleles in Amerindians support the hypothesis that both European and Amerindian ancestral chromosomes might have introduced the disease to the Mexican population, which was further disseminated through mestizaje.

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AIM: To isolate and characterize rhizobacteria from Theobroma cacao with antagonistic activity against Phytophthora palmivora, the causal agent of the black pod rot, which is one of the most important diseases of T. cacao. METHODS AND RESULTS: Among 127 rhizobacteria isolated from cacao rhizosphere, three isolates (CP07, CP24 and CP30) identified as Pseudomonas chlororaphis, showed in vitro antagonistic activity against P. palmivora. Direct antagonism tested in cacao detached leaves revealed that the isolated rhizobacteria were able to reduce symptom severity upon infection with P. palmivora Mab1, with Ps. chlororaphis CP07 standing out as a potential biocontrol agent. Besides, reduced symptom severity on leaves was also observed in planta where cacao root system was pretreated with the isolated rhizobacteria followed by leaf infection with P. palmivora Mab1. The production of lytic enzymes, siderophores, biosurfactants and HCN, as well as the detection of genes encoding antibiotics, the formation of biofilm, and bacterial motility were also assessed for all three rhizobacterial strains. By using a mutant impaired in viscosin production, derived from CP07, it was found that this particular biosurfactant turned out to be crucial for both motility and biofilm formation, but not for the in vitro antagonism against Phytophthora, although it may contribute to the bioprotection of T. cacao. CONCLUSIONS: In the rhizosphere of T. cacao, there are rhizobacteria, such as Ps. chlororaphis, able to protect plants against P. palmivora. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a theoretical basis for the potential use of Ps. chlororaphis CP07 as a biocontrol agent for the protection of cacao plants from P. palmivora infection.

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Spinocerebellar ataxia type 7 (SCA7) is an inherited neurodegenerative disorder characterized by progressive cerebellar ataxia associated with macular degeneration. We recently described one of the largest series of patients with SCA7 that originated from a founder effect in a Mexican population, which allowed us to perform herein the first comprehensive clinical, neurophysiological, and genetic characterization of Mexican patients with SCA7. In this study, 50 patients, categorized into adult or early phenotype, were clinically assessed using standard neurological exams and genotyped using fluorescent PCR and capillary electrophoresis. Patients with SCA7 exhibited the classical phenotype of the disease characterized by cerebellar ataxia and visual loss; however, we reported, for the first time, frontal-executive disorders and altered sensory-motor peripheral neuropathy in these patients. Semiquantitative analysis of ataxia-associated symptoms was performed using Scale for the Assessment and Rating of Ataxia (SARA) and the Brief Ataxia Rating Scale (BARS) scores, while extracerebellar features were measured employing the Inventory of Non-ataxia Symptoms (INAS) scale. Ataxia rating scales confirmed the critical role size of cytosine-adenine-guanine (CAG) repeat size on age at onset and disease severity, while analysis of CAG repeat instability showed that paternal rather than maternal transmission led to greater instability.

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Spinocerebellar ataxias (SCA) are a heterogeneous group of neurodegenerative disorders. CAG (cytosine-adenine-guanine) trinucleotide repeat expansions in the causative genes have been identified as the cause of different SCA. In this study, we simultaneously genotyped SCA1, SCA2, SCA3, SCA6, and SCA7 applying a fluorescent multiplex polymerase chain reaction assay. We analyzed 10 families with SCA (64 patients) from five different communities of Veracruz, a Mexican southeastern state, and identified 55 patients for SCA7 and 9 for SCA2, but none for SCA1, SCA3, or SCA6. To our knowledge, this sample represents one of the largest series of SCA7 cases reported worldwide. Genotyping of 300 healthy individuals from Mexican population and compiled data from different ethnicities showed discordant results concerning the hypothesis that SCA disease alleles arise by expansion of large normal alleles.

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Spinocerebellar ataxia type 7 (SCA7) is a neurodegenerative disorder characterized by progressive cerebellar ataxia associated with macular degeneration that leads, in the majority of patients, to loss of autonomy and blindness. The cause of the disease has been identified as (CAG) n repeat expansion in the coding sequence of the ATXN7 gene on chromosome 3p21.1. SCA7 is one of the least common genetically verified autosomal dominant cerebellar ataxias found worldwide; however, we previously identified the Mexican population showing high prevalence of SCA7, suggesting the occurrence of a common founder effect. In this study, haplotype analysis using four SCA7 gene-linked markers revealed that all 72 SCA7 carriers studied share a common haplotype, A-254-82-98, for the intragenic marker 3145G/A and centromeric markers D3S1287, D3S1228, and D3S3635, respectively. This multiloci combination is uncommon in healthy relatives and Mexican general population, suggesting that a single ancestral mutation is responsible for all SCA7 cases in this population. Furthermore, genotyping using 17 short tandem repeat markers from the non-recombining region of the Y chromosome and further phylogenetic relationship analysis revealed that Mexican patients possess the Western European ancestry, which might trace the SCA7 ancestral mutation to that world region.

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Introducción: La hipoperfusión cerebral en ratas, mediante la oclusión permanente de las arterias carótidas comunes (OPACC), induce alteraciones de la memoria y el aprendizaje. Los mecanismos moleculares han sido poco estudiados y el objetivo del trabajo consiste en caracterizar las alteraciones del metabolismo oxidativo, de la memoria y del aprendizaje. Métodos: Mediante la OPACC se determinó a las 24 h y 22 días de la lesión la actividad de la superóxido dismutasa y la catalasa en el hipocampo, la corteza y el cuerpo estriado. Se realizó una tinción con hematoxilina-eosina y un marcaje con GFAP de cortes coronales. Los trastornos conductuales se exploraron mediante la prueba del laberinto acuático de Morris. Resultados: La lesión indujo un incremento (p<0,01) de la actividad de la catalasa en la corteza a las 24 h, mientras que la superóxido dismutasa aumentó significativamente (p<0,01) en la corteza y el hipocampo a los 22 días. Se observó una intensa vacuolización y pérdida neuronal. La respuesta glial estuvo incrementada en la corteza y el cuerpo estriado. Fue perceptible la afectación en la visión (p<0,001), y las latencias de escape al evaluar la memoria a largo y corto plazo aumentaron considerablemente (p<0,05) en ambos grupos de animales lesionados. Conclusiones: Los cambios en las actividades de las enzimas apuntan a una posible implicación del disbalance oxidativo en la patología asociada a la hipoperfusión cerebral crónica. La OPACC resulta útil para entender los mecanismos por los cuales la hipoperfusión cerebral conduce a las alteraciones de los procesos de memoria y aprendizaje(AU)

Introduction: Chronic hypoperfusion in rats produces memory and learning impairments due to permanent occlusion of commun carotid arteries (POCCA). Molecular mechanisms leading to behavioural disorders have been poorly studied. For this reason, the aim of the present study was to characterise oxidative metabolism disorders and their implications in memory and learning impairments. Methods: Superoxide dismutase (SOD) and catalase (CAT) activities were determined in cortex, hippocampus and striatum homogenates at 24hours and at 22 days after the lesion. Haematoxylin–eosin staining and glial fibrillary acidic protein (GFAP) immunoreactivity were performed on coronal sections. Behavioural impairments were explored using the Morris water maze (MWM). Escape latencies were determined in all behavioural studies. Results: The lesion induced a significant increase (P<0.01) in CAT activity in the cortex at 24hours, while SOD activity was significantly higher (P<0.01) in the cortex and hippocampus at 22 days. An intense vacuolization was observed in the cortex and striatum as a result of the lesion. A neuronal loss in the striatum and hippocampus was observed. The glial reaction increased in the cortex and striatum. Visual alterations were observed in the lesion group with the lowest evolution time (P<0.001). Escape latencies, corresponding to MWM schemes for long-term and short-term memory evaluation increased significantly (P<0.05) in both groups of lesioned animals. Conclusion: It was concluded that changes in SOD and CAT activities indicate a possible implication of oxidative imbalance in the pathology associated with chronic cerebral hypoperfusion. In addition, the POCCA model in rats is useful for understanding mechanisms by which cerebral hypoperfusion produces memory and learning impairments(AU)

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INTRODUCTION: Chronic hypoperfusion in rats produces memory and learning impairments due to permanent occlusion of commun carotid arteries (POCCA). Molecular mechanisms leading to behavioural disorders have been poorly studied. For this reason, the aim of the present study was to characterise oxidative metabolism disorders and their implications in memory and learning impairments. METHODS: Superoxide dismutase (SOD) and catalase (CAT) activities were determined in cortex, hippocampus and striatum homogenates at 24 hours and at 22 days after the lesion. Haematoxylin-eosin staining and glial fibrillary acidic protein (GFAP) immunoreactivity were performed on coronal sections. Behavioural impairments were explored using the Morris water maze (MWM). Escape latencies were determined in all behavioural studies. RESULTS: The lesion induced a significant increase (P<.01) in CAT activity in the cortex at 24 hours, while SOD activity was significantly higher (P<.01) in the cortex and hippocampus at 22 days. An intense vacuolization was observed in the cortex and striatum as a result of the lesion. A neuronal loss in the striatum and hippocampus was observed. The glial reaction increased in the cortex and striatum. Visual alterations were observed in the lesion group with the lowest evolution time (P<.001). Escape latencies, corresponding to MWM schemes for long-term and short-term memory evaluation increased significantly (P<.05) in both groups of lesioned animals. CONCLUSION: It was concluded that changes in SOD and CAT activities indicate a possible implication of oxidative imbalance in the pathology associated with chronic cerebral hypoperfusion. In addition, the POCCA model in rats is useful for understanding mechanisms by which cerebral hypoperfusion produces memory and learning impairments.

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Se considera que la mayoría de las dietas occidentales satisfacen los requerimientos diarios de cobre debido a su presencia ubicua en los alimentos. Estudios recientes han demostrado que el cobre alimentario se encuentra a menudo por debajo de sus requerimientos diarios, lo que puede determinar una carencia de este elemento. Esta carencia está asociada con hipercolesterolemia e hipertrigliceridemia, tanto en humanos como en animales experimentales. En el presente estudio de intervención se examonó el efecto de la administración de 5mg de Cu/día, en 73 pacientes (grupo tratado), de ambos géneros, con edades entre 26y 48 años, con niveles séricos elevados de colesterol total y triglicéridos sin tratamiento con drogas hipolipémicas y se comparó con 73 pacientes hiperlipémicos no sometidos a tratamiento con Cu (grupo control), quienes fueron agrupados por género, edad, peso corporal, consumo de cigarrillos, ingesta de calorías y grasas y actividad física. Antes de administrar el cobre, se extrajo una muestra de sangre para las determinaciones de cobre, cinc y lípidos séricos. Al final del período experimental (45 días), se obtuvo una muestra de sangre para las determinaciones correspondientes. Los resultados sufieren la existencia de una cerencia marginal del elemento traza en el 38 por ciento de los sujetos y demuestran que el cobre disminuye significativamente (p<0.05) los nivles séricos del colesterol total (r=-0.976), de triglicéricos (r=-0.972), de LDL-colesterol (r=-0.961) y de cinc (r=-0.980) con un ligero incremento (r=-0.984) del HDL- colesterol. Estos hallazgos demuestran que el cobre se puede emplear en el tratamiento de los pacientes con hipercolesterolemia e hipertrigliceridemia; aunque los mecanismos, que explican como el cobre determina estos cambios, no se conocen exactamente

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Los estudios epidemiológicos, clínicos y experimentales asocian los bajos niveles dietéticos y/o séricos de diversos antioxidantes y vitaminas con la incidencia elevada de ciertos tipos de cáncer. El presente estudio investiga el efecto del cáncer sobre la concentración sérica del cinz (Zn) y de la vitamina A (VA). Por esta razón, los niveles de Zn y de VA se determinaron en las muestras de suero de 90 pacientes con diferentes tipos de cáncer (42 de semana, 16 de tracto gastrointestinal, 16 genitourinarios, 8 de piel y 8 en otros sitios) y se compararon con los de 110 personas sanas agrupadas por género e índice de masa corporal (IMC). Las concentraciones de Zn y de VA fueron menores (p<0.05) en los cancerosos. El género, el estado nutricional y el tratamiento no influyen en los niveles séricos de estos micronutrientes. El Zn disminuye significativamente (p<0.05) en los carcinomas del tracto digestivo y de próstata mientras que la vitamina A disminuye (p<0.05) en los carcinomas digestivos. Estos resultados sugieren que la disminución del Zn y de VA en el suero es un signo general de cáncer y la posibilidad de la existencia de una carencia de estos micronutrientes, que deberá ser investigadas en estudios futuros. Por consiguiente, las estrategias para el mejoramiento del estado nutricional del Zn y de la VA, y de otros micronutrientes, mejorarán la calidad de vida de estos pacientes

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It has been assumed that most Western diets satisfy the requirement of copper/day because of ubiquitous presence of this element in most foods. Recent studies have shown that dietary copper (Cu) may often fall below the estimated daily requirements, what could determine a deficiency of this trace element. This deficiency is associated with hypercholesterolemia and hypertrigliceridemia, both in human and experimental animals. In the present intervention study was examined the effect of the administration of 5 mg of Cu/day in 73 patients (treated group), of both genders, with ages between 26 and 48 years, with high serum levels of total cholesterol and triglycerides without pharmacological treatment and compared with 73 hyperlipemic subjects non-treated with copper (control group) who were matched by gender, age, body weight, smoking habits, calories and fat intake, and physical activity. Before copper administration, a sample of blood was obtained for serum determinations of copper, zinc and lipids. At the end of the experimental period (45 days), a new sample of blood was taken for the corresponding determinations. The results suggest the existence of a marginal deficiency of the trace element in 38% of the subjects and demonstrate that copper supplementation decreases (p < 0.05) serum levels of total cholesterol (r = -0.976), triglycerides (r = -0.972), LDL-cholesterol (r = -0.961) and zinc (r = -0.980) with a slight increment (r = 0.894) of HDL-cholesterol. These findings demonstrate that copper can be used in the treatment of the patients with hypercholesterolemia and hypertriglyceridemia. The mechanisms by which Cu determines these changes are not known.

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Copper (Cu) deficiency is associated with changes in arterial pressure. The effect depends of the age of initiation of the copper-deficient diet. Copper deficiency started at a young age causes hypotension. When initiated in older or adult animals, copper deficiency can cause hypertension. A case-control study was carried out to investigate the effect of administrating 5 mg Cu/d in 60 subjects, both genders, with mild stable hypertension, pharmacologically untreated (treated group) and compared with 60 hypertensives (control group) who were matched by gender, age, body weight, smoking habits, calories, fat and salt intake (NaCl), and physical activity. Hypertension was diagnosed when the blood pressure was > 150/95 mm Hg. Mean age, mean corporal weight and risk factors were similar in both groups. The results suggested the existence of a marginal deficiency of the trace element in 62% of subjects and demonstrated that Cu decreases systolic (r = -0.963) and diastolic (r = -0.981) blood pressures in treated group (p < 0.05). Control patients did not show significant changes in their arterial pressures. These findings indicate a functional alteration in human blood pressure regulation during mild copper depletion and suggest that Cu could be used in the treatment of stable moderate arterial hypertension. Further investigation is needed to determine the extent of this influence.

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Copper (Cu) deficiency is associated with changes in arterial pressure. The effect depends of the age of initiation of the copper-deficient diet. Copper deficiency started at a young age causes hypotension. When initiated in older or adult animals, copper deficiency can cause hypertension. A case-control study was carried out to investigate the effect of administrating 5 mg Cu/d in 60 subjects, both genders, with mild stable hypertension, pharmacologically untreated (treated group) and compared with 60 hypertensives (control group) who were matched by gender, age, body weight, smoking habits, calories, fat and salt intake (NaCl), and physical activity. Hypertension was diagnosed when the blood pressure was > 150/95 mm Hg. Mean age, mean corporal weight and risk factors were similar in both groups. The results suggested the existence of a marginal deficiency of the trace element in 62 per cent of subjects and demonstrated that Cu decreases systolic (r = -0.963) and diastolic (r = -0.981) blood pressures in treated group (p < 0.05). Control patients did not show significant changes in their arterial pressures. These findings indicate a functional alteration in human blood pressure regulation during mild copper depletion and suggest that Cu could be used in the treatment of stable moderate arterial hypertension. Further investigation is needed to determine the extent of this influence.

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In Spain mumps vaccine is given at the age of 15 months together with measles and rubella vaccines since 1982. Increased numbers of cases and outbreaks of mumps appeared in several autonomous communities in 1995. An outbreak of mumps in the province of.

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In Spain mumps vaccine is given at the age of 15 months together with measles and rubella vaccines since 1982. Increased numbers of cases and outbreaks of mumps appeared in several autonomous communities in 1995. An outbreak of mumps in the province of -

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