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1.
PLoS One ; 18(7): e0288257, 2023.
Article in English | MEDLINE | ID: mdl-37437036

ABSTRACT

The goal of this study was to verify the effect of heterogeneity of variance (HV) on milk production in up to 305 days of lactation (L305) of daughters of Girolando, Gir and Holstein sires, as well as in the genetic evaluation of these sires and their progenies. in Brazil. The model included contemporary groups (consisting of herd, year and calving season) as a fixed effect, cow age at calving (linear and quadratic effects) and heterozygosity (linear effect) as covariates, in addition to the random effects of direct additive genetic and environmental, permanent and residual. The first analysis consisted of the single-trait animal model, with L305 records (disregarding HV). The second considered classes of standard deviations (SD): two-trait model including low and high classes (considering HV), according to the standardized means of L305 for herd-year of calving. The low SD class was composed of herds with SD equal to or less than zero and the high class with positive SD values. Estimates of (co)variance components and breeding values were obtained separately for each scenario using Bayesian inference via Gibbs sampling. Different heritability was estimated. Higher for the high DP class in the Gir (0.20) and Holstein (0.15) breeds, not occurring the same in the Girolando breed, with a lower value among the classes for the high DP (0.10). High values of genetic correlations were also found between low and high SD classes (0.88; 0.85 and 0.79) for the Girolando, Gir and Holstein breeds, respectively. Like the order correlations (Spearman) which were also high for the three breeds analyzed (equal to or above 0.92). Thus, the presence of HV had a smaller impact for L305 and did not affect the genetic evaluation of sires.


Subject(s)
Cobalt , Milk , Female , Animals , Cattle/genetics , Bayes Theorem , Brazil , Heterozygote
2.
PLoS One ; 18(6): e0287056, 2023.
Article in English | MEDLINE | ID: mdl-37294791

ABSTRACT

Our aim was to evaluate the use and application of different nonlinear mixed models, as well as to compare them with approach in nonlinear fixed models, for describing the growth curve of meat-type quails according to gender. A total of 15,002 and 15,408 records of males and females were used, respectively. The body weights were regressed on age of the animals using nonlinear models (Brody; Gompertz; Logistic, Morgan-Mercer-Flodin, Richards and Von Bertalanffy). All model parameters were considered fixed, whereas parameters related to asymptotic weight and maturity rate were fitted as random effects. The Bayesian Information Criterion was used to find the model of best fit. For both genders, the model that used the Morgan-Mercer-Flodin function with the inclusion of asymptotic weight as a random effect was considered the best-fitting model because it reduced the residual variance and increased the accuracy. Based on the lower absolute growth rate and growth velocity of male quails compared to that of females, it can be inferred that males should be slaughtered later. Given the results of this study, it can contribute to the current knowledge about animal yield, specifically at the best moment to slaughter and, this sense, improv the quality genetic of the populations in time.


Subject(s)
Nonlinear Dynamics , Quail , Animals , Female , Male , Bayes Theorem , Body Weight , Models, Biological
3.
Cells ; 11(17)2022 08 31.
Article in English | MEDLINE | ID: mdl-36078125

ABSTRACT

Chikungunya (CHIKV) is an arthritogenic alphavirus that causes a self-limiting disease usually accompanied by joint pain and/or polyarthralgia with disabling characteristics. Immune responses developed during the acute phase of CHIKV infection determine the rate of disease progression and resolution. Annexin A1 (AnxA1) is involved in both initiating inflammation and preventing over-response, being essential for a balanced end of inflammation. In this study, we investigated the role of the AnxA1-FPR2/ALX pathway during CHIKV infection. Genetic deletion of AnxA1 or its receptor enhanced inflammatory responses driven by CHIKV. These knockout mice showed increased neutrophil accumulation and augmented tissue damage at the site of infection compared with control mice. Conversely, treatment of wild-type animals with the AnxA1 mimetic peptide (Ac2-26) reduced neutrophil accumulation, decreased local concentration of inflammatory mediators and diminished mechanical hypernociception and paw edema induced by CHIKV-infection. Alterations in viral load were mild both in genetic deletion or with treatment. Combined, our data suggest that the AnxA1-FPR2/ALX pathway is a potential therapeutic strategy to control CHIKV-induced acute inflammation and polyarthralgia.


Subject(s)
Chikungunya Fever , Inflammation , Adaptor Proteins, Signal Transducing/metabolism , Animals , Annexin A1/genetics , Annexin A1/metabolism , Arthralgia , Chikungunya Fever/metabolism , Inflammation/metabolism , Mice , Mice, Knockout , Receptors, Formyl Peptide/metabolism
4.
Langmuir ; 35(41): 13340-13350, 2019 Oct 15.
Article in English | MEDLINE | ID: mdl-31536356

ABSTRACT

The effect of polymer surfactant structure and concentration on the self-assembly, mechanical properties, and solidification of nanoparticle surfactants (NPSs) at the oil-water interface was studied. The surface tension of the oil-water interface was found to depend strongly on the choice of the polymer surfactant used to assemble the NPSs, with polymer surfactants bearing multiple polar groups being the most effective at reducing interfacial tension and driving the NPS assembly. By contrast, only small variations in the shear modulus of the system were observed, suggesting that it is determined largely by particle density. In the presence of polymer surfactants bearing multiple functional groups, NPS assemblies on pendant drop surfaces were observed to spontaneously solidify above a critical polymer surfactant concentration. Interfacial solidification accelerated rapidly as polymer surfactant concentration was increased. On long timescales after solidification, pendant drop interfaces were observed to spontaneously wrinkle at sufficiently low surface tensions (approximately 5 mN m-1). Interfacial shear rheology of the NPS assemblies was elastic-dominated, with the shear modulus ranging from 0.1 to 1 N m-1, comparable to values obtained for nanoparticle monolayers elsewhere. Our work paves the way for the development of designer, multicomponent oil-water interfaces with well-defined mechanical, structural, and functional properties.

5.
Nitric Oxide ; 78: 60-71, 2018 08 01.
Article in English | MEDLINE | ID: mdl-29857061

ABSTRACT

Activation of 5' adenosine monophosphate-activated protein kinase (AMPK) stimulates production of the gaseous mediators nitric oxide (NO) and carbon monoxide (CO), which are involved in mucosal defense and gastroprotection. As AMPK itself has gastroprotective effects against several gastric ulcer etiologies, in the present study, we aimed to elucidate whether AMPK may also prevent ethanol-induced injury and play a key role in the associated gastroprotection mediated by hydrogen sulfide (H2S), NO, and CO. Mice were pretreated with AICAR (20 mg/kg, an AMPK activator) alone or with 50% ethanol. Other groups were pretreated with respective gaseous mediator inhibitors PAG, l-NAME, or ZnPP IX 30 min prior to AICAR, or with gaseous mediator donors NaHS, Lawesson's reagent and l-cysteine (H2S), SNP, l-Arginine (NO), Hemin, or CORM-2 (CO) 30 min prior to ethanol with or without compound C (10 mg/kg, a non-selective AMPK inhibitor). H2S, nitrate/nitrite (NO3-/NO2-), bilirubin levels, GSH and MDA concentration were evaluated in the gastric mucosa. The gastric mucosa was also collected for histopathological analysis and AMPK expression assessment by immunohistochemistry. Pretreatment with AICAR attenuated the ethanol-induced injury and increased H2S and bilirubin levels but not NO3-/NO2- levels in the gastric mucosa. In addition, inhibition of H2S, NO, or CO synthesis exacerbated the ethanol-induced gastric damage and inhibited the gastroprotection by AICAR. Pretreatment with compound C reversed the gastroprotective effect of NaHS, Lawesson's reagent, l-cysteine, SNP, l-Arginine, CORM-2, or Hemin. Compound C also reversed the effect of NaHS on H2S production, SNP on NO3-/NO2- levels, and Hemin on bilirubin levels. Immunohistochemistry revealed that AMPK is present at basal levels mainly in the gastric mucosa cells, and was increased by pretreatment with NaHS, SNP, and CORM-2. In conclusion, our findings indicate that AMPK activation exerts gastroprotection against ethanol-induced gastric damage and mutually interacts with H2S, NO, or CO to facilitate this process.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Carbon Monoxide/metabolism , Gasotransmitters/metabolism , Hydrogen Sulfide/metabolism , Nitric Oxide/metabolism , Stomach Diseases/prevention & control , Aminoimidazole Carboxamide/analogs & derivatives , Aminoimidazole Carboxamide/pharmacology , Animals , Bilirubin/metabolism , Enzyme Activation , Enzyme Activators/pharmacology , Ethanol , Female , Gastric Mucosa/pathology , Male , Mice , Ribonucleotides/pharmacology , Stomach Diseases/chemically induced
6.
Nitric Oxide ; 76: 152-163, 2018 06 01.
Article in English | MEDLINE | ID: mdl-28943473

ABSTRACT

Hydrogen sulphide (H2S) is a gasotransmitter that participates in various physiological and pathophysiological processes within the gastrointestinal tract. We studied the effects and possible mechanism of action of H2S in secretory diarrhoea caused by cholera toxin (CT). The possible mechanisms of action of H2S were investigated using an intestinal fluid secretion model in isolated intestinal loops on anaesthetized mice treated with CT. NaHS and Lawesson's reagent and l-cysteine showed antisecretory activity through reduction of intestinal fluid secretion and loss of Cl- induced by CT. Pretreatment with an inhibitor of cystathionine-γ-lyase (CSE), dl-propargylglycine (PAG), reversed the effect of l-cysteine and caused severe intestinal secretion. Co-treatment with PAG and a submaximal dose of CT increased intestinal fluid secretion, thus supporting the role of H2S in the pathophysiology of cholera. CT increased the expression of CSE and the production of H2S. Pretreatment with PAG did not reverse the effect of SQ 22536 (an AC inhibitor), bupivacaine (inhibitor of cAMP production), KT-5720 (a PKA inhibitor), and AICAR (an AMPK activator). The treatment with Forskolin does not reverse the effects of the H2S donors. Co-treatment with either NaHS or Lawesson's reagent and dorsomorphin (an AMPK inhibitor) did not reverse the effect of the H2S donors. H2S has antisecretory activity and is an essential molecule for protection against the intestinal secretion induced by CT. Thus, H2S donor drugs are promising candidates for cholera therapy. However, more studies are needed to elucidate the possible mechanism of action.


Subject(s)
Cholera Toxin/antagonists & inhibitors , Diarrhea/chemically induced , Diarrhea/drug therapy , Hydrogen Sulfide/pharmacology , Signal Transduction , AMP-Activated Protein Kinases/metabolism , Adenylyl Cyclases/metabolism , Animals , Cholera Toxin/pharmacology , Cyclic AMP/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Female , Male , Mice
7.
J Pharm Pharmacol ; 69(12): 1773-1785, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28940490

ABSTRACT

OBJECTIVES: We aimed to determine whether carvacryl acetate acts as a TRPA1 receptor agonist and its effects against irinotecan (CPT-11) induced intestinal mucositis in mice. METHODS: TRPA1 structure was obtained from a protein databank, and the 3D structure of carvacryl acetate was determined. Appropriate binding conformations were discovered via automatic docking simulations. To determine the effect of carvacryl acetate in vivo, mice were treated with either DMSO 2%, CPT-11, carvacryl acetate followed by CPT-11, or HC-030031, a TRPA1 antagonist, followed by carvacryl acetate. Jejunum samples were taken and structural, inflammatory and antioxidant parameters were studied. KEY FINDINGS: Eight amino acids residues in TRPA1 established stable interactions with carvacryl acetate, which led to pharmacological efficacy against CPT-11-induced intestinal mucositis via reduction of both neutropenia and bacteremia, increase in villi height and crypt depth, decrease in pro-inflammatory cytokines (interleukin-1ß, keratinocyte chemoattractant and tumour necrosis factor-α) and decrease in malondialdehyde and nitric oxide metabolite levels in the jejunum. CONCLUSIONS: Carvacryl acetate is a promising anti-inflammatory and antioxidant agent, a fact confirmed through observations of its interactions with TRPA1 in CPT-11-induced intestinal mucositis in mice.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Camptothecin/analogs & derivatives , Monoterpenes/pharmacology , Mucositis/prevention & control , Animals , Antineoplastic Agents, Phytogenic/toxicity , Antioxidants/pharmacology , Bacteremia/prevention & control , Camptothecin/toxicity , Cytokines/metabolism , Female , Intestinal Mucosa/drug effects , Intestinal Mucosa/pathology , Irinotecan , Jejunum/metabolism , Jejunum/pathology , Mice , Molecular Docking Simulation , Mucositis/chemically induced , Neutropenia/prevention & control , TRPA1 Cation Channel/agonists
8.
Langmuir ; 33(40): 10501-10510, 2017 10 10.
Article in English | MEDLINE | ID: mdl-28889742

ABSTRACT

In a refinery, undesired high levels of salt concentration in crude oils are reduced by the contact of water with crude oils, where an emulsion is formed. Later, the separation of the water from the desalted oil is essential for the quality of both wastewater discharge and refined oil. However, complex components of crude oils such as asphaltenes may stabilize these emulsions, causing difficulties in efficient separation. Here, we show the coalescence inhibition caused by asphaltene adsorption for both water-in-oil and oil-in-water emulsions, where the oil phase consists of a simple model of asphaltenes dissolved in toluene. We find that oil-in-water emulsions are less stable than water-in-oil emulsions by using a newly developed instrument where controlled experiments can be performed to measure the coalescence time of a single droplet against an oil/water interface as a function of asphaltene aging (associated with the adsorption process of asphaltene molecules onto the interfaces) and asphaltene concentration. Furthermore, we find that the coalescence time for water droplets exhibits a maximum because of a spontaneous emulsification at the oil/water interface that produces droplets consisting of asphaltene-laden water droplets.

9.
Soft Matter ; 12(46): 9266-9279, 2016 Nov 23.
Article in English | MEDLINE | ID: mdl-27752701

ABSTRACT

Understanding and enabling the control of the properties of foams is important for a variety of commercial processes and consumer products. In these systems, the role of surface active compounds has been the subject of many investigations using a wide range of techniques. The study of their influence on simplified geometries such as two bubbles in a liquid or a thin film of solution (such as in the well-known Scheludko cell), has yielded important fundamental understanding. Similarly, in this work an interferometric technique is used to study the dynamic evolution of the film formed by a single bubble being pressed against a planar air-liquid interface. Here interferometry is used to dynamically measure the total volume of liquid contained within the thin-film region between the bubble and the planar interface. Three different small-molecule, surfactant solutions were investigated and the data obtained via interferometry were compared to measurements of the density of bulk foams of the same solutions. The density measurements were collected with a simple, but novel technique using a conical-shaped bubbling apparatus. The results reveal a strong correlation between the measurements on single bubbles and complete foams. This suggests that further investigations using interferometric techniques can be instrumental to building a more detailed mechanistic understanding of how different surface-active compounds influence foam properties. The results also reveal that the commonly used assumption that surfactant-laden interfaces may be modeled as immobile, is too simplistic to accurately model interfaces with small-molecule surfactants.

10.
Int J Biol Macromol ; 86: 865-75, 2016 May.
Article in English | MEDLINE | ID: mdl-26879913

ABSTRACT

Seaweeds are sources of diverse bioactive compounds, such as sulphated polysaccharides. This study was designed to evaluate the chemical composition and anti-diarrheal activity of a fraction of sulphated polysaccharide (PLS) obtained from the red seaweed Hypnea musciformis in different animal models, and to elucidate the underlying mechanisms. PLS was obtained by aqueous extraction, with a yield of 31.8% of the seaweed dry weight. The total carbohydrate content accounted for 99% of the sample. The sulfate content of the polysaccharide was 5.08% and the percentage of carbon was 25.98%. Pretreatment with all doses of PLS inhibited castor oil-induced diarrhea, with reduction of the total amount of stool, diarrheal stools, and the severity of diarrhea. PLS (90 mg/Kg) decreased castor oil- and PGE2-induced enteropooling. In addition, PLS (90 mg/Kg) increased the Na(+)/K(+)-ATPase activity in the small intestine and reduced gastrointestinal transit, possibly via activation of cholinergic receptors. Interestingly, the cholera toxin-induced fluid secretion and Cl(-) ion levels decreased in the intestinal contents of the animals pretreated with PLS (90 mg/kg), probably via reduction of toxin-GM1 receptor binding. In conclusion, PLS exerts anti-diarrheal activity by increasing Na(+)/K(+)-ATPase activity, inhibiting gastrointestinal motility, and blocking the toxin-GM1 receptor binding.


Subject(s)
Diarrhea/drug therapy , Polysaccharides/chemistry , Polysaccharides/pharmacology , Rhodophyta/chemistry , Sulfates/chemistry , Animals , Castor Oil/adverse effects , Cholera Toxin/toxicity , Diarrhea/chemically induced , Diarrhea/metabolism , Diarrhea/physiopathology , Female , Gastrointestinal Transit/drug effects , Intestinal Absorption/drug effects , Intestine, Small/drug effects , Intestine, Small/metabolism , Intestine, Small/physiopathology , Male , Mice , Narcotic Antagonists/pharmacology , Polysaccharides/therapeutic use , Rats , Receptors, Cell Surface/metabolism , Sodium-Potassium-Exchanging ATPase/metabolism
11.
J Ethnopharmacol ; 174: 299-307, 2015 Nov 04.
Article in English | MEDLINE | ID: mdl-26297843

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Anacardium occidentale L. (Anacardiaceae) is commonly known as the cashew tree. It is native to tropical America and extracts of the leaves, bark, roots, chestnut net and exudate have been traditionally used in northeast Brazil for the treatment of various diseases. The exudate of the cashew tree (cashew gum) has been exploited by locals since ancient times for multiple applications, including the treatment of diarrheal diseases. AIM OF THE STUDY: The primary aim of the present study is to evaluate the antidiarrheal activity of cashew gum (CG), a complex heteropolysaccharide from the exudate of the cashew tree, using various models. MATERIALS AND METHODS: The antidiarrheal activity of cashew gum (CG) against acute diarrhea was investigated using the castor oil-induced diarrhea model. The effects of CG on gastrointestinal transit and castor oil- and PGE2- induced enteropooling were also examined in rodents. In addition, the effect of CG against secretory diarrhea was investigated using a model of fluid secretion in cholera toxin-treated intestinal closed loops in live mice. RESULTS: Cashew gum (30, 60, and 90 mg/kg, p.o.) showed a significant (P<0.05-0.01) antidiarrheal effect in rats with castor oil-induced diarrhea, inhibiting the total amount of stool and diarrheal stools. The 60 mg/kg dose of CG exhibited excellent antidiarrheal activity and significantly reduced the severity of diarrhea (diarrhea scores) in rats. CG (60 mg/kg) significantly (P<0.05) decreased the volume of castor oil- and PGE2-induced intestinal fluid secretion (enteropooling). In addition, similar to loperamide (standard drug, 5 mg/kg, p.o.), CG treatment reduced the distance traveled by a charcoal meal in the 30-min gastrointestinal transit model by interacting with opioid receptors. In cholera toxin-induced secretory diarrhea, CG (60 mg/kg) significantly inhibited the intestinal fluid secretion and decreased Cl(-) ion loss in the cholera toxin(-)treated isolated loops model of live mice by competitively binding to cholera toxin-GM1 receptors. CONCLUSIONS: In conclusion, our results indicate that a complex heteropolysaccharide extracted from the exudate of A. occidentale L. has antidiarrheal activity in acute, inflammatory, and secretory diarrhea models, which could justify its traditional use in the treatment of diarrhea in northeast Brazil. The antidiarrheal activity might be explained by the capacity of CG to inhibit gastrointestinal motility and thereby reduce the accumulation of intestinal fluid and the secretion of water and chloride ions in the lumen of the intestine.


Subject(s)
Anacardium , Antidiarrheals/therapeutic use , Diarrhea/drug therapy , Plant Extracts/therapeutic use , Plant Gums/therapeutic use , Animals , Antidiarrheals/isolation & purification , Castor Oil/toxicity , Diarrhea/chemically induced , Diarrhea/physiopathology , Female , Male , Mice , Plant Extracts/isolation & purification , Plant Gums/isolation & purification , Polysaccharides/isolation & purification , Polysaccharides/therapeutic use , Rats , Rats, Wistar
12.
Rev Bras Reumatol ; 54(4): 268-72, 2014.
Article in Portuguese | MEDLINE | ID: mdl-25627221

ABSTRACT

OBJECTIVES: To describe the clinical characteristics and the occurrence of atypical arthritis in children diagnosed with rheumatic fever (RF) and followed in tertiary care clinics in Salvador, Bahia, Brazil. METHODOLOGY: A descriptive study of a case series, of the initial clinical presentation, and of recurrence in 41 children diagnosed with RF. RESULTS: Of the patients studied (n=41), 61% were male, mean age of 9.2 years, and mean age at diagnosis between 5 and 16 years. Arthritis was present in 75.6% of patients; carditis in 75.6%; chorea in 31.7%; erythema marginatum in 14.6%; and subcutaneous nodules in 4.9%. An atypical pattern was observed in 22 of 31 cases of arthritis (70.9%): involvement of small joints and/or axial skeleton in 12 cases (38.7%); >3 weeks of duration in 9 (29%); inadequate response to NSAIDs in 2 (6.5%); oligoarthritis (≤4 joints) in 22/31 (71%), with monoarthritis in 6/31 (1 in the foot, 1 in the ankle, and 4 in the knee). Fever was present in 78% of the cases, and 82.9% of patients were regularly on secondary prophylaxis. CONCLUSION: Atypical arthritis was present in most patients presenting with joint involvement, being a confounding factor against a proper diagnosis and of therapeutic delay.


Subject(s)
Arthritis/etiology , Rheumatic Fever/complications , Adolescent , Child , Child, Preschool , Female , Humans , Male , Retrospective Studies
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