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1.
J Environ Manage ; 233: 768-773, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30318156

RESUMEN

This work focuses on the evaluation of the electrochemical dewatering of sludge polluted with model hazardous species. To do this, two sludge samples taken from the outlet of the anaerobic digesters of the municipal Wastewater Treatment Facility of Ciudad Real were polluted with herbicide clopyralid (CP) and with antibiotics amoxicillin (AMX) and ampicillin (AMP), respectively. These sludge samples underwent first dewatering by press filtration and then, the dewatering continued by the application of an electrochemically assisted driven process with increasing electric fields (1.0, 2.0 and 3.0 V cm-1). Results demonstrate that the electrochemically-assisted process can help to exhaust the pollutant adsorbed onto the sludge and attain a supplemental removal (up to 15%) of water in both cases. This is a highly important result, because it can help to develop technologies for sludge treatment that avoid the diffusion of hazardous pollution during the land application of the sludge. No reactivity of the pollutants was observed during the tests.


Asunto(s)
Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Electricidad , Filtración , Aguas Residuales , Agua
2.
Genet Mol Res ; 16(2)2017 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-28510257

RESUMEN

Water deficit is the main reason for instability in the context of soybean culture. The development of strategies for the selection of more tolerant genotypes is necessary. These strategies include the use of polyethylene glycol 6000 solutions (PEG-6000) for conducting the germination test under conditions of water restriction. Thus, the objective of this study was to determine the osmotic potential and the main characteristics that promote the discrimination of soybean genotypes with regard to water stress tolerance during germination and the vigor test. Thirteen soybean cultivars were used. The seeds were allowed to germinate on sheets of germitest paper moistened in solution with PEG-6000, simulating different levels of water availability, which is expressed as osmotic potential (0.0, -0.2, -0.4, and -0.6 MPa). We assessed germination, length, and dry mass for seedlings and seeds, as well as reserve dynamics. Germination and variables related to the dynamics of reservation have great influence on the expression of variability in environments under stress. Among the different osmotic potentials, the -0.2 MPa was the most efficient for the expression of genetic variability among the cultivars. Conducting the germination test with PEG-6000 solution to -0.2 MPa was efficient for selecting soybean cultivars tolerant to water stress. This was accomplished by evaluating the percentage of germination, along with variables related to the dynamics of reservation.


Asunto(s)
Sequías , Genotipo , Germinación/genética , Glycine max/genética , Fitomejoramiento/métodos , Selección Genética , Adaptación Fisiológica , Presión Osmótica , Glycine max/crecimiento & desarrollo , Glycine max/fisiología
3.
Genet Mol Res ; 15(3)2016 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-27706707

RESUMEN

Leishmaniasis is a disease caused by protozoa of the genus Leishmania. Two distinct forms are recognized: visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL). In the Americas, the causative agent of VL is L. infantum chagasi, whereas L. braziliensis is principally responsible for CL. Domestic dogs constitute the main source of VL in urban environments, and have also been implicated in CL epidemiology. We carried out molecular and serological surveys to detect Leishmania infection in dogs from the municipality of Ituberá in Bahia, Brazil. Furthermore, we identified risk factors associated with illness in dogs from this locality. Blood samples were collected from 399 dogs and tested using an indirect immunofluorescence assay (IFA) and polymerase chain reaction (PCR) to detect Leishmania spp antibodies and L. infantum chagasi and L. braziliensis DNA, respectively. Dogs were clinically evaluated and tissue samples from those exhibiting skin lesions were examined for parasites. In addition, the dog owners completed an epidemiological questionnaire to identify factors associated with infection. Skin lesions consistent with CL were found on 37 (9.3%) of the evaluated animals, but parasitological examination was negative for all samples. The IFA returned positive results for 60 (15%) dogs. PCR identified DNA from L. braziliensis in 86 (21.6%) animals, where as all samples proved negative for L. infantum chagasi. The 134 dogs (33.6%) testing positive using IFA and/ or PCR were considered infected, and of these, only 13 demonstrated skin lesions. Animals from rural areas were 3.39-times more likely to be infected compared to those in urban environments.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , ADN Protozoario/genética , Enfermedades de los Perros/epidemiología , Leishmania braziliensis/aislamiento & purificación , Leishmaniasis Cutánea/epidemiología , Leishmaniasis Cutánea/veterinaria , Animales , Brasil/epidemiología , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/transmisión , Perros , Femenino , Técnica del Anticuerpo Fluorescente/veterinaria , Incidencia , Leishmania braziliensis/genética , Leishmania braziliensis/inmunología , Leishmaniasis Cutánea/parasitología , Leishmaniasis Cutánea/transmisión , Masculino , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Factores de Riesgo
4.
Genet Mol Res ; 15(3)2016 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-27706560

RESUMEN

In Brazil, canine hepatozoonosis is a tick-borne subclinical hemoparasitosis caused by a protozoa Hepatozoon canis and is highly prevalent in dogs in rural areas. An epizootiological study was conducted to investigate the prevalence of H. canis in the canine population of Ituberá, Bahia, and to analyze any associated risk factors. Blood samples were collected from 380 dogs and determined the presence of the protozoan by performing capillary blood smear and polymerase chain reaction (PCR). Epizootiological data were collected by asking dog owners to answer a structured questionnaire. H. canis gamonts were not detected in the blood smears. However, PCR detected H. canis in 163/380 (42.9%) dogs examined. Physical examination and anamnesis indicated 105 (64.4%) positive asymptomatic dogs. Hematological alterations were observed in 115 (70.5%) infected dogs. No clinical, hematological, or epizootiological variable was found to be significantly associated to the infection. In conclusion, the high prevalence of H. canis infection in local dogs may be because of the peri-urban features of this municipality. Moreover, to the best of our knowledge, this study the first study to report H. canis infection in the State of Bahia.


Asunto(s)
Coccidiosis/veterinaria , Enfermedades de los Perros/epidemiología , Animales , Brasil/epidemiología , Coccidios/genética , Coccidiosis/epidemiología , Coccidiosis/parasitología , Estudios Transversales , Enfermedades de los Perros/parasitología , Perros , Femenino , Masculino , Técnicas de Diagnóstico Molecular , Reacción en Cadena de la Polimerasa , Prevalencia
5.
J Dairy Sci ; 98(6): 3826-39, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25864049

RESUMEN

With the objective to optimize fixed-time artificial insemination (FTAI) protocols based on estradiol benzoate (EB) and progesterone (P4), we performed 2 experiments (Exp.) in dairy cows. In Exp. 1 (n=44), we hypothesized that increased EB (EB3=3 mg vs. EB2=2 mg) on d 0 would improve synchronization of ovarian follicle wave emergence. Likewise, in Exp. 2 (n=82), we hypothesized that a GnRH treatment on d -3 (early in a follicular wave on d 0) versus d -7 (presence of a dominant follicle on d 0) would better synchronize wave emergence. Moreover, results from both experiments were combined to identify reasons for the lack of synchronization. All cows were treated with EB at the time of introduction of a P4 implant (d 0). On d 7, cows were given 25 mg of prostaglandin F2α; on d 8, the implant was removed and cows were given 1mg of estradiol cypionate. All cows received FTAI on d 10. In both experiments, daily ultrasound evaluations were performed and, in Exp. 2, circulating P4 was evaluated during the protocol. Pregnancy per artificial insemination (P/AI) was determined on d 31 and 59 after FTAI. In Exp. 1, EB dose did not change time to wave emergence, but EB3 compared with EB2 decreased the percentage of cows with a corpus luteum on d 7 (19.8 vs. 55.3%) and time to ovulation (10.4 vs. 10.9 d). In Exp. 2, although we detected a tendency for delayed follicle wave emergence after the start of the FTAI protocol in cows ovulating to GnRH given on d -7, there was no difference in percentage of cows with a synchronized wave emergence (~80%). Regardless of treatment, more cows with P4<0.1 ng/mL, compared with P4≥0.1 and <0.22 ng/mL at the time of AI, ovulated to the protocol (81.2 vs. 58.0%) and had increased P/AI (47.4 vs. 21.4%). An analysis of data from both experiments showed that only 73.8% (93/126) of cows had synchronized wave emergence, and only 77.8% (98/126) of cows ovulated at the end of the protocol. Fertility was much greater in cows that had emergence of a new wave synchronized and ovulated to end of the protocol [P/AI 61.3% (46/75)] compared with cows that failed to present one or both of the outcomes above [15.7% (8/51)]. Thus, although current FTAI protocols using EB and P4 produce P/AI between 30 and 40% for lactating dairy cows, there remains room for improvement because less than 60% (75/126) of the cows were correctly synchronized. Starting the FTAI protocol without the dominant follicle or increasing the dose of EB to 3mg was not effective in increasing synchronization rate.


Asunto(s)
Bovinos , Estradiol/análogos & derivados , Hormona Liberadora de Gonadotropina/administración & dosificación , Inseminación Artificial/veterinaria , Animales , Cuerpo Lúteo/efectos de los fármacos , Dinoprost/administración & dosificación , Estradiol/administración & dosificación , Sincronización del Estro/métodos , Femenino , Fertilidad/efectos de los fármacos , Inseminación Artificial/métodos , Lactancia , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Ovulación/efectos de los fármacos , Inducción de la Ovulación/métodos , Inducción de la Ovulación/veterinaria , Embarazo , Progesterona/administración & dosificación , Progesterona/sangre , Factores de Tiempo , Resultado del Tratamiento
6.
Genet Mol Res ; 14(3): 8219-28, 2015 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-26345747

RESUMEN

The objective of this study was to select genitors based on F1 and F2 generations, evaluated in different environments, to obtain segregating populations for the identification of strains showing improved earliness, yield, and carioca-type grains. Nine bean strains were crossed in a partial diallel scheme (4 x 5), in which group 1 included 4 strains with early cycles and group 2 included 5 elite strains. The F1 and F2 generations and the genitors were assessed in Coimbra and Viçosa in randomized blocks with 3 replications. The following characteristics were evaluated: days between sowing and emergence, and grain yield. We observed an interaction between the effects of general combining ability and specific combining ability with the environments (crop, location, and generation) for both grain earliness and yield. Genetic analysis of earliness revealed a predominance of additive effects and grain yield dominance effects. The strain Goiano Precoce may be used as a genitor in breeding programs to improve earliness, while strains RP1 and VC33 can be used to increase grain yield. We observed genetic complementation between strains Goiano Precoce and RP1, BRSMG Madrepérola and BRS Estilo for earliness and between RP1 and Rosinha Precoce for grain yield.


Asunto(s)
Alelos , Cruzamientos Genéticos , Ambiente , Fabaceae/genética , Hibridación Genética
7.
Bull Entomol Res ; 104(1): 65-78, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24112240

RESUMEN

In this study, we use DNA barcodes for species delimitation to solve taxonomic conflicts in 86 specimens of 14 species belonging to the Corynoneura group (Diptera: Chironomidae: Orthocladiinae), from the Atlantic Forest, Brazil. Molecular analysis of cytochrome c-oxidase subunit I (COI) gene sequences supported 14 cohesive species groups, of which two similar groups were subsequently associated with morphological variation at the pupal stage. Eleven species previously described based on morphological criteria were linked to DNA markers. Furthermore, there is the possibility that there may be cryptic species within the Corynoneura group, since one group of species presented internal grouping, although no morphological divergence was observed. Our results support DNA-barcoding as an excellent tool for species delimitation in groups where taxonomy by means of morphology is difficult or even impossible.


Asunto(s)
Chironomidae/anatomía & histología , Chironomidae/genética , Clasificación/métodos , Código de Barras del ADN Taxonómico/métodos , Filogenia , Animales , Brasil , Chironomidae/clasificación , Complejo IV de Transporte de Electrones/genética , Funciones de Verosimilitud , Modelos Genéticos , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Especificidad de la Especie
8.
Reprod Domest Anim ; 49(3): 476-80, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24731188

RESUMEN

The aim of this study was to evaluate the effect of leptin administration during superovulation on in vivo goat embryo production. Ten mature does were superovulated with 133 mg follicle-stimulating hormone (FSH) i.m. in six descending doses at 12-h intervals. The goats received 4.8 µg/kg human recombinant leptin s.c. (leptin group, n = 5) or phosphate-buffered saline (PBS) (control group, n = 5) with the first and second FSH doses. The does were mated and subjected to embryo collection by transcervical technique 6 days later. The total number of cells per embryo and the number of cells with fragmented DNA were assessed in selected blastocysts by combining Hoechst 33342 and terminal dUTP nick-end labelling (TUNEL) staining. Plasma concentrations of oestradiol (E2 ) and progesterone (P4 ) were determined by electrochemiluminescence from the day of FSH treatment, on the day of superovulatory oestrus and on the day before embryo collection. Compared with the control group, the does that received leptin had a higher number of transferable embryos (p < 0.005), fewer embryos classified as degenerated (p < 0.001) and fewer TUNEL-positive cells/blastocyst (p < 0.001). The number of transferable embryos was positively correlated with E2 concentrations on day of oestrus (r = 0.562; p < 0.01) and P4 concentrations on the day of embryo collection (r = 0.912; p < 0.001). We concluded that in vivo leptin administration during FSH treatment improved embryo quality and affected ovarian steroidogenesis in superovulated goats.


Asunto(s)
Hormona Folículo Estimulante/administración & dosificación , Cabras/embriología , Leptina/administración & dosificación , Animales , Blastocisto/citología , Blastocisto/fisiología , Fragmentación del ADN , Transferencia de Embrión/veterinaria , Estradiol/sangre , Femenino , Humanos , Etiquetado Corte-Fin in Situ/veterinaria , Ovario/efectos de los fármacos , Ovario/metabolismo , Embarazo , Progesterona/sangre , Proteínas Recombinantes/administración & dosificación , Esteroides/biosíntesis , Superovulación
9.
Med Intensiva ; 38(7): 444-54, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25060511

RESUMEN

OBJECTIVE: To investigate the applications and effects of neuromuscular electrical stimulation (NMES) in critically ill patients in ICU by means of a systematic review. MATERIALS AND METHODS: Electronic searches were conducted in the databases Medline, CINAHL, Cochrane Central Register of Controlled Trials, Web of Science, Embase, ProQuest Health and Medical Complete, AMED, and PEDro. The PEDro score was used to assess the methodological quality of the eligible studies. RESULTS: The search yielded a total of 9759 titles and nine articles satisfied the eligibility criteria. These studies showed that NMES can maintain or increase muscle mass, strength and volume, reduce time in mechanical ventilation and weaning time, and increase muscle degradation in critically ill patients in ICU. Two studies allowed a meta-analysis of the effects of NMES on quadriceps femoris strength and it showed a significant effect in favor of NMES in the Medical Research Council (MRC) Scale (standardized mean difference 0.77 points; p=0.02; 95% CI: 0.13-1.40). CONCLUSIONS: The selected studies showed that NMES has good results when used for the maintenance of muscle mass and strength in critically ill patients in ICU. Future studies with high methodological quality should be conducted to provide more evidence for the use of NMES in an ICU setting.


Asunto(s)
Enfermedad Crítica/terapia , Estimulación Eléctrica , Humanos , Debilidad Muscular/terapia
10.
Braz J Biol ; 84: e278013, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38422288

RESUMEN

Colloidal systems have been used to encapsulate, protect and release essential oils in mouthwashes. In this study, we investigated the effect of cetylpyridinium chloride (CPC) on the physicochemical properties and antimicrobial activity of oil-in-water colloidal systems containing tea tree oil (TTO) and the nonionic surfactant polysorbate 80. Our main aim was to evaluate whether CPC could improve the antimicrobial activity of TTO, since this activity is impaired when this essential oil is encapsulated with polysorbate 80. These systems were prepared with different amounts of TTO (0-0.5% w/w) and CPC (0-0.5% w/w), at a final concentration of 2% (w/w) polysorbate 80. Dynamic light scattering (DLS) results revealed the formation of oil-swollen micelles and oil droplets as a function of TTO concentration. Increases in CPC concentrations led to a reduction of around 88% in the mean diameter of oil-swollen micelles. Although this variation was of only 20% for the oil droplets, the samples appearance changed from turbid to transparent. The surface charge of colloidal structures was also markedly affected by the CPC as demonstrated by the transition in zeta potential from slightly negative to highly positive values. Electron paramagnetic resonance (EPR) studies showed that this transition is followed by significant increases in the fluidity of surfactant monolayer of both colloidal structures. The antimicrobial activity of colloidal systems was tested against a Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureaus) bacteria. Our results revealed that the inhibition of bacterial growth is observed for the same CPC concentration (0.05% w/w for E. coli and 0.3% w/w for S. aureus) regardless of TTO content. These findings suggest that TTO may not act as an active ingredient in polysorbate 80 containing mouthwashes.


Asunto(s)
Aceites Volátiles , Aceite de Árbol de Té , Emulsiones/química , Emulsiones/farmacología , Polisorbatos/farmacología , Polisorbatos/química , Micelas , Staphylococcus aureus , Escherichia coli , Antisépticos Bucales/farmacología , Tensoactivos/farmacología , Tensoactivos/química , Aceites Volátiles/farmacología , Antibacterianos/farmacología , Aceite de Árbol de Té/farmacología
11.
Physiol Genomics ; 45(21): 1012-20, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-24022219

RESUMEN

Meat quality traits are economically important because they affect consumers' acceptance, which, in turn, influences the demand for beef. However, selection to improve meat quality is limited by the small numbers of animals on which meat tenderness can be evaluated due to the cost of performing shear force analysis and the resultant damage to the carcass. Genome wide-association studies for Warner-Bratzler shear force measured at different times of meat aging, backfat thickness, ribeye muscle area, scanning parameters [lightness, redness (a*), and yellowness] to ascertain color characteristics of meat and fat, water-holding capacity, cooking loss (CL), and muscle pH were conducted using genotype data from the Illumina BovineHD BeadChip array to identify quantitative trait loci (QTL) in all phenotyped Nelore cattle. Phenotype count for these animals ranged from 430 to 536 across traits. Meat quality traits in Nelore are controlled by numerous QTL of small effect, except for a small number of large-effect QTL identified for a*fat, CL, and pH. Genomic regions harboring these QTL and the pathways in which the genes from these regions act appear to differ from those identified in taurine cattle for meat quality traits. These results will guide future QTL mapping studies and the development of models for the prediction of genetic merit to implement genomic selection for meat quality in Nelore cattle.


Asunto(s)
Bovinos/genética , Genoma , Carne/normas , Sitios de Carácter Cuantitativo/genética , Tejido Adiposo/metabolismo , Algoritmos , Animales , Teorema de Bayes , Mapeo Cromosómico , Cromosomas de los Mamíferos/genética , Estudios de Asociación Genética , Genotipo , Concentración de Iones de Hidrógeno , Carne/análisis , Fenotipo , Polimorfismo de Nucleótido Simple , Factores de Tiempo
12.
Biochemistry (Mosc) ; 78(2): 194-203, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23581990

RESUMEN

The in vitro effects of BaltTX-I, a catalytically inactive Lys49 variant of phospholipase A2 (PLA2), and BaltTX-II, an Asp49 catalytically active PLA2 isolated from Bothrops alternatus snake venom, on thioglycollate-elicited macrophages (TG-macrophages) were investigated. At non-cytotoxic concentrations, the secretory PLA2 BaltTX-I but not BaltTX-II stimulated complement receptor-mediated phagocytosis. Pharmacological treatment of TG-macrophages with staurosporine, a protein kinase C (PKC) inhibitor, showed that this kinase is involved in the increase of serum-opsonized zymosan phagocytosis induced by BaltTX-I but not BaltTX-II secretory PLA2, suggesting that PKC may be involved in the stimulatory effect of this toxin in serum-opsonized zymosan phagocytosis. Moreover, BaltTX-I and -II induced superoxide production by TG-macrophages. This superoxide production stimulated by both PLA2s was abolished after treatment of cells with staurosporine, indicating that PKC is an important signaling pathway for the production of this radical. Our experiments showed that, at non-cytotoxic concentrations, BaltTX-I may upregulate phagocytosis via complement receptors, and that both toxins upregulated the respiratory burst in TG-macrophages.


Asunto(s)
Bothrops , Macrófagos/efectos de los fármacos , Fosfolipasas A2/farmacología , Venenos de Serpiente/química , Secuencia de Aminoácidos , Animales , Supervivencia Celular/efectos de los fármacos , Macrófagos/citología , Masculino , Ratones , Datos de Secuencia Molecular , Fosfolipasas A2/aislamiento & purificación , Alineación de Secuencia , Superóxidos/metabolismo
13.
Braz J Med Biol Res ; 56: e12742, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37377307

RESUMEN

Brain glucose hypometabolism and neuroinflammation are early pathogenic manifestations in neurological disorders. Neuroinflammation may also disrupt leptin signaling, an adipokine that centrally regulates appetite and energy balance by acting on the hypothalamus and exerting neuroprotection in the hippocampus. The Goto-Kakizaki (GK) rat is a non-obese type 2 diabetes mellitus (T2DM) animal model used to investigate diabetes-associated molecular mechanisms without obesity jeopardizing effects. Wistar and GK rats received the maintenance adult rodent diet. Also, an additional control group of Wistar rats received a high-fat and high-sugar diet (HFHS) provided by free consumption of condensed milk. All diets and water were provided ad libitum for eight weeks. Brain glucose uptake was evaluated by 2-deoxy-2-[fluorine-18] fluoro-D-glucose under basal (saline administration) or stimulated (CL316,243, a selective ß3-AR agonist) conditions. The animals were fasted for 10-12 h, anesthetized, and euthanized. The brain was quickly dissected, and the hippocampal area was sectioned and stored at -80°C in different tubes for protein and RNA analyses on the same animal. GK rats exhibited attenuated brain glucose uptake compared to Wistar animals and the HFHS group under basal conditions. Also, the hippocampus of GK rats displayed upregulated leptin receptor, IL-1ß, and IL-6 gene expression and IL-1ß and the subunit of the transcription factor NF-κB (p-p65) protein expression. No significant alterations were detected in the hippocampus of HFHS rats. Our data indicated that a genetic predisposition to T2DM has significant brain deteriorating features, including brain glucose hypometabolism, neuroinflammation, and leptin signaling disruption in the hippocampal area.


Asunto(s)
Diabetes Mellitus Tipo 2 , Glucosa , Ratas , Animales , Glucosa/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ratas Wistar , Leptina , Glucemia/metabolismo , Enfermedades Neuroinflamatorias , Encéfalo/metabolismo , Obesidad , Hipocampo/metabolismo , Inflamación , Insulina
14.
Interface Focus ; 9(3): 20180066, 2019 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-31065339

RESUMEN

Electrostatic interactions play a pivotal role in many biomolecular processes. The molecular organization and function in biological systems are largely determined by these interactions. Owing to the highly negative charge of RNA, the effect is expected to be more pronounced in this system. Moreover, RNA base pairing is dependent on the charge of the base, giving rise to alternative secondary and tertiary structures. The equilibrium between uncharged and charged bases is regulated by the solution pH, which is therefore a key environmental condition influencing the molecule's structure and behaviour. By means of constant-pH Monte Carlo simulations based on a fast proton titration scheme, coupled with the coarse-grained model HiRE-RNA, molecular dynamic simulations of RNA molecules at constant pH enable us to explore the RNA conformational plasticity at different pH values as well as to compute electrostatic properties as local pK a values for each nucleotide.

15.
Braz. j. med. biol. res ; 56: e12742, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1447690

RESUMEN

Brain glucose hypometabolism and neuroinflammation are early pathogenic manifestations in neurological disorders. Neuroinflammation may also disrupt leptin signaling, an adipokine that centrally regulates appetite and energy balance by acting on the hypothalamus and exerting neuroprotection in the hippocampus. The Goto-Kakizaki (GK) rat is a non-obese type 2 diabetes mellitus (T2DM) animal model used to investigate diabetes-associated molecular mechanisms without obesity jeopardizing effects. Wistar and GK rats received the maintenance adult rodent diet. Also, an additional control group of Wistar rats received a high-fat and high-sugar diet (HFHS) provided by free consumption of condensed milk. All diets and water were provided ad libitum for eight weeks. Brain glucose uptake was evaluated by 2-deoxy-2-[fluorine-18] fluoro-D-glucose under basal (saline administration) or stimulated (CL316,243, a selective β3-AR agonist) conditions. The animals were fasted for 10-12 h, anesthetized, and euthanized. The brain was quickly dissected, and the hippocampal area was sectioned and stored at -80°C in different tubes for protein and RNA analyses on the same animal. GK rats exhibited attenuated brain glucose uptake compared to Wistar animals and the HFHS group under basal conditions. Also, the hippocampus of GK rats displayed upregulated leptin receptor, IL-1β, and IL-6 gene expression and IL-1β and the subunit of the transcription factor NF-κB (p-p65) protein expression. No significant alterations were detected in the hippocampus of HFHS rats. Our data indicated that a genetic predisposition to T2DM has significant brain deteriorating features, including brain glucose hypometabolism, neuroinflammation, and leptin signaling disruption in the hippocampal area.

16.
Artículo en Inglés | MEDLINE | ID: mdl-28702191

RESUMEN

BACKGROUND: Genomic growth curves are generally defined only in terms of population mean; an alternative approach that has not yet been exploited in genomic analyses of growth curves is the Quantile Regression (QR). This methodology allows for the estimation of marker effects at different levels of the variable of interest. We aimed to propose and evaluate a regularized quantile regression for SNP marker effect estimation of pig growth curves, as well as to identify the chromosome regions of the most relevant markers and to estimate the genetic individual weight trajectory over time (genomic growth curve) under different quantiles (levels). RESULTS: The regularized quantile regression (RQR) enabled the discovery, at different levels of interest (quantiles), of the most relevant markers allowing for the identification of QTL regions. We found the same relevant markers simultaneously affecting different growth curve parameters (mature weight and maturity rate): two (ALGA0096701 and ALGA0029483) for RQR(0.2), one (ALGA0096701) for RQR(0.5), and one (ALGA0003761) for RQR(0.8). Three average genomic growth curves were obtained and the behavior was explained by the curve in quantile 0.2, which differed from the others. CONCLUSIONS: RQR allowed for the construction of genomic growth curves, which is the key to identifying and selecting the most desirable animals for breeding purposes. Furthermore, the proposed model enabled us to find, at different levels of interest (quantiles), the most relevant markers for each trait (growth curve parameter estimates) and their respective chromosomal positions (identification of new QTL regions for growth curves in pigs). These markers can be exploited under the context of marker assisted selection while aiming to change the shape of pig growth curves.

17.
Protein Sci ; 10(7): 1415-25, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11420443

RESUMEN

Monte Carlo simulations are used to assess the adequacy of the Tanford-Kirkwood prescription for electrostatic interactions in macromolecules. Within a continuum dielectric framework, the approach accurately describes salt screening of electrostatic interactions for moderately charged systems consistent with common proteins at physiological conditions. The limitations of the Debye-Hückel theory, which forms the statistical mechanical basis for the Tanford-Kirkwood result, become apparent for highly charged systems. It is shown, both by an analysis of the Debye-Hückel theory and by numerical simulations, that the difference in dielectric permittivity between macromolecule and surrounding solvent does not play a significant role for salt effects if the macromolecule is highly charged. By comparison to experimental data, the continuum dielectric model (combined with either an approximate effective Hamiltonian as in the Tanford-Kirkwood treatment or with exact Monte Carlo simulations) satisfactorily predicts the effects of charge mutation on metal ion binding constants, but only if the macromolecule and solvent are assigned the same or similar permittivities.


Asunto(s)
Modelos Moleculares , Proteínas/química , Proteínas/metabolismo , Animales , Sitios de Unión , Cationes/metabolismo , Humanos , Método de Montecarlo , Concentración Osmolar , Sales (Química)/farmacología , Solventes/farmacología , Electricidad Estática
18.
Neuroscience ; 41(2-3): 425-31, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1870698

RESUMEN

Experiments were carried out to test whether changes in the sensitivity of hippocampal pyramidal neurons to the neurotransmitters glutamate, GABA and noradrenaline may be associated with the establishment of an epileptogenic focus induced by kindling. The effects of iontophoretically applied neurotransmitters on the firing rate of single units were quantified in the rat hippocampal CA1 area in kindled and control animals. Kindling was induced by electrical tetanic stimulation of the Schaffer collateral/commissural fibers. Firing was evoked by local glutamate iontophoresis while simultaneous GABA or noradrenaline application suppressed this response. A significant reduction of the GABAergic inhibitory action on the firing rate in kindled animals studied around four or around 42 days after the last convulsion was found. In the same neurons, the suppressive effect of noradrenaline was not different from controls. The neurons of kindled animals, investigated around four days after the last seizure, had a reduced sensitivity for glutamate; more glutamate ejection current was needed to evoke firing or to evoke the maximum firing rate. In contrast, the responsiveness for glutamate was significantly increased long-term after the last convulsion. These findings demonstrate that hippocampal Schaffer collateral kindling is associated with a long-lasting reduced effectiveness of the GABA-mediated response on glutamate-evoked firing in CA1.


Asunto(s)
Epilepsia/fisiopatología , Glutamatos/farmacología , Hipocampo/fisiopatología , Excitación Neurológica , Neuronas/fisiología , Norepinefrina/farmacología , Tractos Piramidales/fisiopatología , Ácido gamma-Aminobutírico/farmacología , Análisis de Varianza , Animales , Potenciales Evocados/efectos de los fármacos , Hipocampo/efectos de los fármacos , Hipocampo/fisiología , Masculino , Neuronas/efectos de los fármacos , Tractos Piramidales/efectos de los fármacos , Tractos Piramidales/fisiología , Ratas , Ratas Endogámicas , Factores de Tiempo
19.
Int J Dev Neurosci ; 19(7): 649-53, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11705669

RESUMEN

The main objective of the present study was to characterize the inhibition by phenylalanine and phenylpyruvate of ATP diphosphohydrolase activity in synaptosomes from the brain cortex of rats. This enzyme participates together with a 5'-nucleotidase in adenosine formation from the neurotransmitter, ATP, in the synaptic cleft. The inhibition of ATP diphosphohydrolase was competitive for nucleotide hydrolysis but 5'-nucleotidase was not affected by these metabolites. Furthermore, the two substances inhibited enzyme activity by acting at the same binding site. If the enzyme inhibition observed in vitro also occurs in the brain of PKU patients, it may promote an increase in ATP levels in the synaptic cleft. In this case, the neurotoxicity of ATP could possibly be one of the mechanisms leading to the characteristic brain damage of phenylketonuria.


Asunto(s)
Adenosina Trifosfato/metabolismo , Apirasa/metabolismo , Corteza Cerebral/enzimología , Fenilalanina/metabolismo , Fenilcetonurias/enzimología , Ácidos Fenilpirúvicos/metabolismo , Terminales Presinápticos/enzimología , 5'-Nucleotidasa/antagonistas & inhibidores , 5'-Nucleotidasa/metabolismo , Adenosina/biosíntesis , Adenosina Difosfato/metabolismo , Animales , Apirasa/antagonistas & inhibidores , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiopatología , Hidrólisis/efectos de los fármacos , Cinética , Fenilalanina/farmacología , Fenilcetonurias/fisiopatología , Ácidos Fenilpirúvicos/farmacología , Terminales Presinápticos/efectos de los fármacos , Ratas , Ratas Wistar , Sinaptosomas
20.
Braz J Med Biol Res ; 35(5): 581-7, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12011944

RESUMEN

An association between depression and altered immune and hormonal systems has been suggested by the results of many studies. In the present study we carried out immune and hormonal measurements in 40 non-medicated, ambulatory adult patients with depression determined by CID-10 criteria and compared with 34 healthy nondepressed subjects. The severity of the condition was determined with the Hamilton Depression Rating Scale. Of 40 depressed patients, 31 had very severe and 9 severe or moderate depression, 29 (72.5%) were females and 11 (27.5%) were males (2.6:1 ratio). The results revealed a significant reduction of albumin and elevation of alpha-1, alpha-2 and beta-globulins, and soluble IL-2 receptor in patients with depression compared to the values obtained for nondepressed subjects (P<0.05). The decrease lymphocyte proliferation in response to a mitogen was significantly lower in severely or moderately depressed patients when compared to control (P<0.05). These data confirm the immunological disturbance of acute phase proteins and cellular immune response in patients with depression. Other results may be explained by a variety of interacting factors such as number of patients, age, sex, and the nature, severity and/or duration of depression. Thus, the data obtained should be interpreted with caution and the precise clinical relevance of these findings requires further investigation.


Asunto(s)
Citocinas/sangre , Depresión/inmunología , Depresión/metabolismo , Hormonas/sangre , Adolescente , Adulto , Proteínas Sanguíneas/metabolismo , División Celular , Citocinas/metabolismo , Femenino , Hormonas/metabolismo , Humanos , Linfocitos/citología , Masculino , Persona de Mediana Edad , Receptores de Interleucina-2/sangre , Receptores de Interleucina-2/metabolismo , Albúmina Sérica/metabolismo , Seroglobulinas/metabolismo , Índice de Severidad de la Enfermedad
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