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1.
J Invertebr Pathol ; 187: 107702, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34902396

RESUMEN

The presence of pathogen agents in shrimp farming is the main obstacle for successful aquaculture. Vibrio species are naturally part of water because they play an important role as opportunistic bacteria. Vibrio parahaemolyticus was identified as the causative agent of the Early Mortality Syndrome in 2009, causing the loss of shrimp farming worldwide. Dunaliella sp. flour has been tested against Vibrio infection proving to be an effective prophylactic method that decreases mortality and improves physiological and immune response in Litopenaeus vannamei. Juvenile shrimp were exposed to 2% Dunaliella sp. flour and commercial 1.1% ß -glucan diet provided every other day for 15 days and a posterior infection with V. parahaemolyticus (1 × 106 CFU/mL). To evaluate shrimp stress status, some parameters as glucose, lactate, cholesterol, triglycerides, relative superoxide dismutase (SOD) gene expression and circulating hemocytes were analyzed in hemolymph at zero and seven days before infection and at 0, 24, and 48 h post-infection. L. vannamei fed with Dunaliella sp. showed 93% and ß -glucan 87% survival, compared with 79% in the infected control group. Additionally, Dunaliella sp. improved hemocyte and lipid concentrations compared to ß -glucan while both immunostimulants showed an increase in SOD response against bacteria. The addition of 2% Dunaliella sp. every other day in L. vannamei diet enhanced stress response against V. parahaemolyticus infection.


Asunto(s)
Penaeidae , Vibriosis , Vibrio parahaemolyticus , beta-Glucanos , Animales , Antioxidantes , Dieta , Harina , Inmunidad Innata
2.
Am J Otolaryngol ; 42(5): 103017, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33857782

RESUMEN

PURPOSE: To evaluate the effectiveness and ease of N95 respirator decontamination methods in a clinic setting and to identify the extent of microbial colonization on respirators associated with reuse. METHODS: In a prospective fashion, N95 respirators (n = 15) were randomized to a decontamination process (time, dry heat, or ultraviolet C light [UVC]) in outpatient clinics. Each respirator was re-used up to 5 separate clinic sessions. Swabs on each respirator for SARS-CoV-2, bacteria, and fungi were obtained before clinic, after clinic and post-treatment. Mask integrity was checked after each treatment (n = 68). Statistical analyses were performed to determine factors for positive samples. RESULTS: All three decontamination processes reduced bacteria counts similarly. On multivariate mixed model analysis, there were an additional 8.1 colonies of bacteria (95% CI 5.7 to 10.5; p < 0.01) on the inside compared to the outside surface of the respirators. Treatment resulted in a decrease of bacterial load by 8.6 colonies (95% CI -11.6 to -5.5; p < 0.01). Although no decontamination treatment affected the respirator filtration efficiency, heat treatments were associated with the breakdown of thermoplastic elastomer straps. Contamination with fungal and SARS-CoV-2 viral particles were minimal to non-existent. CONCLUSIONS: Time, heat and UVC all reduced bacterial load on reused N95 respirators. Fungal contamination was minimal. Heat could permanently damage some elastic straps making the respirators nonfunctional. Given its effectiveness against microbes, lack of damage to re-treated respirators and logistical ease, UVC represents an optimal decontamination method for individual N95 respirators when reuse is necessary.


Asunto(s)
COVID-19/prevención & control , Descontaminación/métodos , Equipo Reutilizado , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/prevención & control , Respiradores N95/microbiología , SARS-CoV-2/aislamiento & purificación , COVID-19/transmisión , Recuento de Colonia Microbiana , Calor , Humanos , Estudios Prospectivos , Factores de Tiempo , Rayos Ultravioleta
3.
J Invertebr Pathol ; 161: 14-22, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30586567

RESUMEN

Carotenoid sources in shrimp diets have shown to be effective for improving survival, growth, reproductive capacity, stress resistance, and also for diminishing disease. Dunaliella sp. is known to have high levels of ß-carotenes, which works as pro-vitamin A, enhancing the immune response in shrimp. However, the administration of Dunaliella sp. in shrimp diet needs to be evaluated to determine the appropriate dose and frequency of administration needed to optimize performance in cultured white shrimp. Diets with three different concentrations of Dunaliella sp. flour (1.5, 2 and 3%) were tested, and each one was administered at three different time frequencies: daily, and at 3- and 7-days intervals. Shrimp fed for 20 days were then infected with Vibrio parahaemolyticus (1 × 106 CFU/mL). Hemolymph parameters including protein, glucose, lactate, cholesterol and triglycerides were analyzed to evaluate shrimp stress status. Additionally, L. vannamei innate non-specific immune response was examined by evaluating the activity of prophenoloxidase (proPO), phenoloxidase (PO) and superoxide dismutase (SOD) in hemolymph; shrimp survival was also recorded. Survival after infection with V. parahaemolyticus was higher for shrimp fed with diets consisting of 2% Dunaliella sp. administered every 3 and 7 days. Shrimp fed a diet consisting of 2% or 3% Dunaliella sp. administered every third day showed positive physiological and immune responses to infection. A decrease in lipid oxidation in plasma triglycerides was observed at 48 h post inoculation in shrimp fed at all diets regimes due to Dunaliella sp. antioxidant action. Experimental results suggest the importance of Dunaliella sp. dosage and feeding frequency in L. vannamei diet to improve the survival and immune response.


Asunto(s)
Microalgas , Penaeidae , Vibriosis/inmunología , Vibrio parahaemolyticus , beta Caroteno/administración & dosificación , Animales , Acuicultura , Catecol Oxidasa/sangre , Chlorophyceae/metabolismo , Dieta/veterinaria , Suplementos Dietéticos , Precursores Enzimáticos/sangre , Hemolinfa/metabolismo , Inmunidad Innata , Microalgas/metabolismo , Monofenol Monooxigenasa/sangre , Penaeidae/inmunología , Penaeidae/microbiología , Alimentos Marinos , Superóxido Dismutasa/sangre , Triglicéridos/sangre , beta Caroteno/farmacología
4.
J Invertebr Pathol ; 148: 118-123, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28625840

RESUMEN

Survival of Litopenaeus vannamei was evaluated during a Vibrio parahaemolyticus infection. This bacteria has been causing significant economic losses in the shrimp industry due to the appearance of early mortality syndrome (EMS), also known as acute hepatopancreatic necrosis disease (AHPND). Control of bacteria in ponds is difficult to achieve with antibiotics due to environmental infections and antibiotic resistance. New methods have been proposed to control and prevent the impact of bacterial infections. The physiological response indicated by plasma biochemical parameters in shrimp can determine their health and stress status. Meanwhile, shrimp immunology is the key factor in establishing strategies to control diseases. Immunostimulants are the best alternative to antibiotics to prevent or minimize disease damage, and at the same time, these stimulants improve the immune system in shrimp. Four diets containing 1.5, 2, 2.5 and 3% of Dunaliella sp. with high ß-carotene content were tested in the present study. After 20days of feeding, organisms were infected with V. parahaemolyticus. Protein, glucose, lactate, triglyceride and cholesterol levels, as well as activity of prophenoloxidase and phenoloxidase, were determined 48 h post-infection (hpi). Shrimp fed a diet with 3% Dunaliella sp. showed the highest survival. Glucose, cholesterol, and triglyceride levels, as well as prophenoloxidase and phenoloxidase activity, were not observed to be suitable indicators during this bacterial infection. The results indicated that the inclusion of Dunaliella sp. in diet increases survival in L. vannamei infected with V. parahaemolyticus.


Asunto(s)
Chlorophyta , Penaeidae/inmunología , Penaeidae/microbiología , Vibrio parahaemolyticus , beta Caroteno/administración & dosificación , Animales , Alimentos Marinos
5.
Parasitol Res ; 116(8): 2341-2346, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28550645

RESUMEN

Our knowledge of the parasite species present in wildlife hosts is incomplete. Protozoans such as amoebae of the genus Entamoeba infect a large variety of vertebrate species, including NHPs. However, traditionally, their identification has been accomplished through microscopic evaluation; therefore, amoeba species have not always been identified correctly. We searched for Entamoeba spp. using a fragment of the small subunit rDNA in free-ranging howler monkeys (Alouatta palliata and A. pigra) from southeast Mexico. One hundred fifty five samples were collected, with 46 from A. palliata and 109 from A. pigra and 8 of the total samples were positive. We detected a new clade of Entamoeba, which was separated from other described species but closer to E. insolita, as well as an unnamed sequence typically found in iguana species with low shared identity values (<90%). We designated this new clade as conditional lineage 8 (CL8) and we have shown that members of this group are not exclusive to reptiles.


Asunto(s)
Alouatta/parasitología , Entamoeba/aislamiento & purificación , Reptiles/parasitología , Animales , Animales Salvajes/genética , Animales Salvajes/parasitología , ADN Ribosómico , Entamoeba/clasificación , Entamoeba/genética , México
6.
Int J Mol Sci ; 17(8)2016 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-27483255

RESUMEN

A sulfated polysaccharide extracted from Navicula sp. presented a yield of 4.4 (% w/w dry biomass basis). Analysis of the polysaccharide using gas chromatography showed that this polysaccharide contained glucose (29%), galactose (21%), rhamnose (10%), xylose (5%) and mannose (4%). This polysaccharide presented an average molecular weight of 107 kDa. Scanning electron microscopy (SEM) micrographs showed that the lyophilized Navicula sp. polysaccharide is an amorphous solid with particles of irregular shapes and sharp angles. The polysaccharide at 1% (w/v) solution in water formed gels in the presence of 0.4% (w/v) FeCl3, showing elastic and viscous moduli of 1 and 0.7 Pa, respectively. SEM analysis performed on the lyophilized gel showed a compact pore structure, with a pore size of approximately 150 nm. Very few studies on the gelation of sulfated polysaccharides using trivalent ions exist in the literature, and, to the best of our knowledge, this study is the first to describe the gelation of sulfated polysaccharides extracted from Navicula sp.


Asunto(s)
Diatomeas/química , Compuestos Férricos/farmacología , Geles/química , Polisacáridos/química , Reología , Sulfatos/química , Cromatografía de Gases , Diatomeas/ultraestructura , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier
7.
Zygote ; 23(6): 813-20, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25255785

RESUMEN

The process of cooling and cryopreservation of prawn embryos is a viable alternative for a continuous supply of larvae for freshwater prawn farming ponds. However, studies involving the application of those techniques as well as on toxicity of cryoprotectants in freshwater prawn embryos are scarce. Thus, this study aims to test the toxicity of methylic alcohol (MET), dimethyl sulfoxide (DMSO) and ethylene glycol (EG) on Macrobrachium amazonicum embryos. For the present experiment, pools of embryos were taken from 15 M. amazonicum females and were divided into three groups and tested in duplicate at concentrations of 10, 5, 3; 1, 0.5 or 0.1%. Toxicity tests were conducted for 24 h in Falcon® pipes to obtain the lethal concentration for 50% of the larvae (LC50). After the set period for testing, random samples of embryos were removed for morphological analysis under stereoscopic microscopes. Results were analysed using analysis of variance (ANOVA) and Tukey's test at a 5% significance level and Trimmed Spearman-Karber Analysis to determine LC50-24 h. DMSO toxicity tests revealed that 5% and 10% concentrations showed the highest toxicity and differed from the control (P ≤ 0.05), 24h-LC50 was 437.4 ± 14.4 µL. MET was less toxic among the tested cryoprotectants and concentrations did not allow the determination of its LC50-24h. For tests with EG, concentrations of 3, 5 or 10% solutions resulted in a 100% mortality to tested embryos; EG was the tested cryoprotectant with the highest toxicity, with an LC50-24h average of 81.91 ± 35.3 µl.


Asunto(s)
Criopreservación/métodos , Crioprotectores/toxicidad , Palaemonidae/efectos de los fármacos , Palaemonidae/embriología , Animales , Dimetilsulfóxido/toxicidad , Relación Dosis-Respuesta a Droga , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/fisiología , Glicol de Etileno/toxicidad , Femenino , Agua Dulce , Larva/efectos de los fármacos , Metanol/toxicidad , Pruebas de Toxicidad/métodos
8.
J Invertebr Pathol ; 117: 9-12, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24424376

RESUMEN

An experimental investigation was performed to evaluate the productive and physiological responses of Litopenaeus vannamei that were infected with WSSV and fed diets enriched with Dunaliella sp., which had a high ß-carotene content induced by nitrogen reduction in the culture medium. A basal diet containing 35% crude protein and experimental diets T1 and T2, which included 1% and 2% microalgae meal, respectively, were evaluated. Positive (infected juveniles) and negative (non-infected) controls were also evaluated. Survival was significantly higher (80%) in the two treatment groups compared to the positive control group (56%). In the negative control group, survival was 100%. Some variation was recorded for hemolymph metabolites among treatments and at distinct times post-infection; although the tendencies were not clear, some metabolites (glucose and triglycerides) appeared to decrease on the last days of the trial, probably due to their use as energy for the shrimp to thrive despite the infection. The results of the study suggest a positive effect of the dietary inclusion of Dunaliella meal on shrimp survival and an unclear effect on hemolymph metabolites.


Asunto(s)
Cianobacterias , Hemolinfa/metabolismo , Penaeidae/virología , Virus del Síndrome de la Mancha Blanca 1 , beta Caroteno/administración & dosificación , Animales , Cianobacterias/metabolismo
9.
Rev Biol Trop ; 62(3): 969-76, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25412529

RESUMEN

Mollusks are some of the most important, abundant and diverse organisms inhabiting not only aquatic ecosystems, but also terrestrial environments. Recently, they have been used for bioremediation of aquaculture effluents; nevertheless, for that purpose it is necessary to analyze the capacity of a particular species. In this context, an experimental investigation was developed to evaluate the performance of two bivalves C. gnidia and D. ponderosa, collected from areas with or without shrimp aquaculture effluents. For this, the filtration capacity (as clearance rate) as well as the oxygen consumption and ammonia excretion rates were measured following standard methods. The clearance rate was significantly higher for D. ponderosa from impacted areas, when com- pared to C. gnidia, from both areas. Contrarily, the oxygen consumption was greater for C. gnidia from impacted areas compared to D. ponderosa from both areas. The same tendency was observed for the ammonia excretion with the highest rates observed for C. gnidia from impacted areas, whereas no differences were observed among D. ponderosa from both areas. The results suggest that both species developed different strategies to thrive and survive under the impacted conditions; D. ponderosa improved its filtration efficiency, while C. gnidia modified its oxygen consumption and ammonia excretion. We concluded that both species, and particularly D. ponderosa, can be used for bioremediation purposes.


Asunto(s)
Compuestos de Amonio/metabolismo , Acuicultura/métodos , Bivalvos/fisiología , Consumo de Oxígeno/fisiología , Penaeidae/crecimiento & desarrollo , Animales , Biodegradación Ambiental , Bivalvos/clasificación , Purificación del Agua/métodos
10.
Gene ; 924: 148589, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-38777108

RESUMEN

Nitrogen is the principal nutrient deficiency that increases lipids and carbohydrate content in diatoms but negatively affects biomass production. Marine diatom Chaetoceros muelleri is characterized by lipid and carbohydrate accumulation under low nitrogen concentration without affecting biomass. To elucidate the molecular effects of nitrogen concentrations, we performed an RNA-seq analysis of C. muelleri grown under four nitrogen concentrations (3.53 mM, 1.76 mM, 0.44 mM, and 0.18 mM of NaNO3). This research revealed that changes in global transcription in C. muelleri are differentially expressed by nitrogen concentration. "Energetic metabolism", "Carbohydrate metabolism" and "Lipid metabolism" pathways were identified as the most upregulated by N deficiency. Due to N limitation, alternative pathways to self-supply nitrogen employed by microalgal cells were identified. Additionally, nitrogen limitation decreased chlorophyll content and caused a greater response at the transcriptional level with a higher number of unigenes differentially expressed. By contrast, the highest N concentration (3.53 mM) recorded the lowest number of differentially expressed genes. Amt1, Nrt2, Fad2, Skn7, Wrky19, and Dgat2 genes were evaluated by RT-qPCR. In conclusion, C. muelleri modify their metabolic pathways to optimize nitrogen utilization and minimize nitrogen losses. On the other hand, the assembled transcriptome serves as the basis for metabolic engineering focused on improving the quantity and quality of the diatom for biotechnological applications. However, proteomic and metabolomic analysis is also required to compare gene expression, protein, and metabolite accumulation.


Asunto(s)
Diatomeas , Nitrógeno , Transcriptoma , Nitrógeno/metabolismo , Diatomeas/metabolismo , Diatomeas/genética , Perfilación de la Expresión Génica/métodos , Metabolismo de los Lípidos/genética , Metabolismo de los Hidratos de Carbono/genética , Redes y Vías Metabólicas/efectos de los fármacos , Redes y Vías Metabólicas/genética , Biomasa
11.
Polymers (Basel) ; 15(13)2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37447425

RESUMEN

We evaluate the effectiveness of chelating resins (CR) derived from Merrifield resin (MR) and 1,2-phenylenediamine (PDA), 2,2'-dipyridylamine (DPA), and 2-(aminomethyl)pyridine (AMP) as adsorbent dosimeters for Ag+, Cu2+, Fe3+, and Pb2+ cations from water under competitive and noncompetitive conditions. MR-PDA, MR-DPA, and MR-AMP were obtained in a 95-97% yield and characterized by IR, fluorescence, and SEM. The ability of CRs as adsorbents was determined by batch and flow procedures. MR-PDA showed a batch adsorption capacity order of Fe3+ (29.8 mg/g) > Ag+ (2.7 mg/g) > Pb2+ (2.6 mg/g) at pH 3.4. The flow adsorption showed affinity towards the Ag+ cation at pH 7 (18.4 mg/g) and a reusability of 10 cycles. In MR-DPA, the batch adsorption capacity order was Ag+ (9.1 mg/g) > Pb2+ (8.2 mg/g) > Cu2+ (3.5 mg/g) at pH 5. The flow adsorption showed affinity to the Cu2+ cation at pH 5 (2.2 mg/g) and a reuse of five cycles. In MR-AMP, the batch adsorption capacity was Ag+ (17.1 mg/g) at pH 3.4. The flow adsorption showed affinity to the Fe3+ cation at pH 2 (4.3 mg/g) and a reuse of three cycles. The three synthesized and reusable CRs have potential as adsorbents for Ag+, Cu2+, Fe3+, and Pb2+ cations and showed versatility in metal removal for water treatment.

12.
Metabolites ; 13(3)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36984806

RESUMEN

There are multiple associations between the different blood groups (ABO and RhD) and the incidence of oxidative stress-related diseases, such as certain carcinomas and COVID-19. Bioactive compounds represent an alternative to its prevention and treatment. Phycobiliproteins (PBP) are bioactive compounds present in the microalga Porphyridium cruentum and, despite its antioxidant activity, their inhibitory effect on hemolysis has not been reported. The aim of this work was to evaluate the erythroprotective potential of phycobiliproteins from P. cruentum in different blood groups. The microalga was cultured in F/2 medium under controlled laboratory conditions. Day 10 of culture was determined as the harvest point. The microalgal biomass was lyophilized and a methanolic (MetOH), Tris HCl (T-HCl), and a physiological solution (PS) ultrasound-assisted extraction were performed. Extract pigments were quantified by spectrophotometry. The antioxidant activity of the extracts was evaluated with the ABTS+•, DPPH•, and FRAP methods, finding that the main antioxidant mechanism on the aqueous extracts was HAT (hydrogen atom transfer), while for MetOH it was SET (single electron transfer). The results of the AAPH, hypotonicity, and heat-induced hemolysis revealed a probable relationship between the different antigens (ABO and RhD) with the antihemolytic effect, highlighting the importance of bio-directed drugs.

13.
ScientificWorldJournal ; 2012: 723654, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22649317

RESUMEN

Shrimp postlarvae were reared into different microcosm systems without water exchange; a traditional system based on simple fertilization to improve microalgae concentration (control), an autotrophic system (AS) based on the promotion of biofloc and biofilm by the addition of fertilizer and artificial substrates and a heterotrophic system (HS) based on the promotion of heterotrophic bacteria by the addition of nitrogenous and carbonaceous sources and artificial substrates. Better growth performance and survival were registered in shrimp from the AS and HS compared to the control. Feed conversion ratios were below 0.7 for all treatments, but AS and HS were significantly lower than the control. Regarding digestive performance, no significant differences were observed for trypsin, amylase and lipase activities among AS and control shrimp; however, shrimp from HS showed a higher trypsin and amylase activities, suggesting a higher digestive activity caused by the presence of microbial bioflocs. The presence of biofilm and bioflocs composed by either autotrophic or heterotrophic organisms in combination with formulated feed improved the growth performance and survival of shrimp. Apparently, such combination fits the nutritional requirements of shrimp.


Asunto(s)
Acuicultura/métodos , Penaeidae/crecimiento & desarrollo , Amilasas/metabolismo , Animales , Procesos Autotróficos/fisiología , Procesos Heterotróficos/fisiología , Lipasa/metabolismo , Penaeidae/enzimología , Tripsina/metabolismo
14.
Metabolites ; 12(12)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36557241

RESUMEN

Previous studies have reported that different blood groups are associated with the risk of chronic degenerative diseases that mainly involve inflammation and neoplastic processes. We investigate the relationship between blood groups and the erythroprotective effect of extracts from Navicula incerta against oxidative damage as a proposal to develop drugs designed for people with a specific blood type related to chronic pathology. The study was carried out through the elucidation of the erythroprotective potential, anti-inflammatory and antiproliferative activity of Navicula incerta. Research suggests that the presence or absence of certain blood groups increases or decreases the abilities of certain phytochemicals to inhibit oxidative stress, which is related to the systemic inflammatory response involved in the development of different types of cancer. The pigment-rich extracts from Navicula incerta inhibit ROO•- induced oxidative stress in human erythrocytes on the A RhD+ve antigen without compromising the structure of the cell membrane. This result is very important, since the A antigen is related to the susceptibility of contracting prostate cancer. Similarly, it was possible to inhibit the proliferation of cervical (HeLa) and prostate (PC-3) carcinoma. The combinatorial analysis of different biological activities can help design phytochemicals as new candidates for preventive drugs treating the chronic degenerative diseases associated with a specific blood group.

15.
Biology (Basel) ; 10(7)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206287

RESUMEN

Diatoms are the most abundant group of phytoplankton, and their success lies in their significant adaptation ability to stress conditions, such as nutrient limitation. Phosphorus (P) is a key nutrient involved in the transfer of energy and the synthesis of several cellular components. Molecular and biochemical mechanisms related to how diatoms cope with P deficiency are not clear, and research into this has been limited to a few species. Among the molecular responses that have been reported in diatoms cultured under P deficient conditions is the upregulation of genes encoding enzymes related to the transport, assimilation, remobilization and recycling of this nutrient. Regarding biochemical responses, due to the reduction of the requirements for carbon structures for the synthesis of proteins and phospholipids, more CO2 is fixed than is consumed by the Calvin cycle. To deal with this excess, diatoms redirect the carbon flow toward the synthesis of storage compounds such as triacylglycerides and carbohydrates, which are excreted as extracellular polymeric substances. This review aimed to gather all current knowledge regarding the biochemical and molecular mechanisms of diatoms related to managing P deficiency in order to provide a wider insight into and understanding of their responses, as well as the metabolic pathways affected by the limitation of this nutrient.

16.
Saudi J Biol Sci ; 28(2): 1401-1416, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33613070

RESUMEN

Navicula incerta is a marine microalga distributed in Baja California, México, commonly used in aquaculture nutrition, and has been extended to human food, biomedical, and pharmaceutical industries due to its high biological activity. Therefore, the study aimed to optimize culture conditions to produce antioxidant pigments. A central composite experimental design and response surface methodology (RSM) was employed to analyze the best culture conditions. The medium (nitrogen-deficient concentrations), salinity (PSU = Practical Salinity Unity [g/kg]), age of culture (days), and solvent extraction (ethanol, methanol, and acetone) were the factors used for the experiment. Chlorophyll a (Chl a) and total carotenoids (T-Car), determined spectroscopically, were used as the response variables. The antioxidant capacity was evaluated by DPPH• and ABTS•+ radical inhibition, FRAP, and anti-hemolytic activity. According to the overlay plots, the optimum growth conditions for Chl a and T-Car production were the following conditions: medium = 0.44 mol·L-1 of NaNO3, salinity = 40 PSU, age of culture: 3.5 days, and solvent = methanol. The pigment extracts obtained in these optimized conditions had high antioxidant activity in ABTS•+ (86.2-92.1% of inhibition) and anti-hemolytic activity (81.8-96.7% of hemolysis inhibition). Low inhibition (33-35%) was observed in DPPH•. The highest value of FRAP (766.03 ± 16.62 µmol TE/g) was observed in the acetonic extract. The results demonstrated that RSM could obtain an extract with high antioxidant capacity with potential applications in the biomedical and pharmaceutical industry, which encourages the use of natural resources for chemoprevention of chronic-degenerative pathologies.

17.
EJVES Short Rep ; 44: 38-43, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31497658

RESUMEN

INTRODUCTION: Acute aortic dissection after endovascular repair of an aortic aneurysm is a rare but serious condition, with potential complications that can result in the death of the patient. REPORT: This is the case of a patient diagnosed with a type IV thoraco-abdominal aneurysm with involvement of both iliac arteries who underwent endovascular repair with a four fenestration device and a left iliac branch. One month after the procedure, the patient presented with a type B acute aortic dissection that extended from the left subclavian artery to the proximal stent of the fenestrated graft. This dissection was treated by thoracic endovascular aortic repair, and after a problematic post-operative period, the patient was discharged after 30 days. DISCUSSION: Occurrence of an acute aortic dissection after endovascular repair of an aortic aneurysm has rarely been reported in the literature. Development of these dissections has been related to factors such as excessive oversizing, use of devices with active fixation systems, or injuries during the procedure, although it is believed that the late onset would indicate that it was a de novo dissection. The presence of an aortic dissection can lead to the collapse and occlusion of the previous endograft and even to aortic rupture, and mortality in reported cases reaches 30%. The authors suggest that endovascular treatment should be considered in these patients.

18.
RSC Adv ; 9(67): 39147-39162, 2019 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-35540649

RESUMEN

A new series of oligomethylene bis(nitrophenylureylbenzamide) receptors were synthesized varying the relative position of the urea and amide groups (ortho4 and meta8) and the length of the oligomethylene chain (C2 to C8). An anion recognition study was performed with TBAX salts (X = AcO-, BzO-, F-, H2PO4 -, and HP2O7 3-) by UV-vis and 1H NMR. The flexibility of these receptors allows a cooperative effect of both ureylbenzamide units in the receptors. Noteworthy, the ortho position favored the 1 : 1 stoichiometry in the complexes with the carboxylates. The formation of 2 : 1 receptor-anion complexes with both types of receptors 4 and 8 and with hydrogen pyrophosphate and high log K values obtained were very significant in this work. The NMR studies evidenced the formation of supramolecular complexes, even in a competitive solvent, such as DMSO.

19.
Cir Cir ; 75(4): 293-6, 2007.
Artículo en Español | MEDLINE | ID: mdl-18053362

RESUMEN

BACKGROUND: Papillary fibroelastoma is a rare benign tumor characterized morphologically since first being described in 1976. Nevertheless, this tumor can be presented with a variety of clinical manifestations, making diagnosis challenging for the physician. There are no gender or age preferences but it is diagnosed by site of presentation along with macro- and microscopic characteristics. CASE REPORT: We report the case of a male patient with a history of type 2 diabetes mellitus and arterial hypertension who was admitted to the hospital with a diagnosis of ischemic heart disease accompanied by sustained ventricular tachycardia. Echocardiogram reported degree I diastolic dysfunction, apical ventricular aneurysm, and unusual apical tumor of the septum and left ventricle. DISCUSSION: Primary heart tumors have an incidence of 0.0017%. The most common symptoms are chest pain, syncope, dyspnea and arrhythmias. Diagnosis is accomplished incidentally by echocardiography, which is usually carried out for other reasons. Surgical procedure of choice is total tumor resection along with valve repair or replacement, if necessary, and in some cases cardiac endothelium resection and repair, with or without pericardium patch replacement. CONCLUSIONS: Papillary fibroelastoma is rare but is a recognized cause of embolic phenomena. Rapid identification followed by surgical resection is curative, precise and well tolerated by the patient.


Asunto(s)
Fibroma/diagnóstico , Neoplasias Cardíacas/diagnóstico , Anciano , Humanos , Masculino
20.
PLoS One ; 12(1): e0169637, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28056072

RESUMEN

Although the presence of cryptic host specificity has been documented in Blastocystis, differences in infection rates and high genetic polymorphism within and between populations of some subtypes (ST) have impeded the clarification of the generalist or specialist specificity of this parasite. We assessed the genetic variability and host specificity of Blastocystis spp. in wild howler monkeys from two rainforest areas in the southeastern region of Mexico. Fecal samples of 225 Alouatta palliata (59) and A. pigra (166) monkeys, belonging to 16 sylvatic sites, were analyzed for infection with Blastocystis ST using a region of the small subunit rDNA (SSUrDNA) gene as a marker. Phylogenetic and genetic diversity analyses were performed according to the geographic areas where the monkeys were found. Blastocystis ST2 was the most abundant (91.9%), followed by ST1 and ST8 with 4.6% and 3.5%, respectively; no association between Blastocystis ST and Alouatta species was observed. SSUrDNA sequences in GenBank from human and non-human primates (NHP) were used as ST references and included in population analyses. The haplotype network trees exhibited different distributions: ST1 showed a generalist profile since several haplotypes from different animals were homogeneously distributed with few mutational changes. For ST2, a major dispersion center grouped the Mexican samples, and high mutational differences were observed between NHP. Furthermore, nucleotide and haplotype diversity values, as well as migration and genetic differentiation indexes, showed contrasting values for ST1 and ST2. These data suggest that ST1 populations are only minimally differentiated, while ST2 populations in humans are highly differentiated from those of NHP. The host generalist and specialist specificities exhibited by ST1 and ST2 Blastocystis populations indicate distinct adaptation processes. Because ST1 exhibits a generalist profile, this haplotype can be considered a metapopulation; in contrast, ST2 exists as a set of local populations with preferences for either humans or NHP.


Asunto(s)
Infecciones por Blastocystis/virología , Blastocystis/patogenicidad , Alouatta , Animales , Blastocystis/clasificación , Blastocystis/genética , ADN Ribosómico/genética , Heces/parasitología , Haplotipos/genética , Especificidad del Huésped , Humanos , Masculino
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