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1.
Pharmaceutics ; 16(5)2024 May 04.
Article in English | MEDLINE | ID: mdl-38794280

ABSTRACT

Silybin (SIB) is a hepatoprotective drug known for its poor oral bioavailability, attributed to its classification as a class IV drug with significant metabolism during the first-pass effect. This study explored the potential of solid lipid nanoparticles with (SLN-SIB-U) or without (SLN-SIB) ursodeoxycholic acid and polymeric nanoparticles (PN-SIB) as delivery systems for SIB. The efficacy of these nanosystems was assessed through in vitro studies using the GRX and Caco-2 cell lines for permeability and proliferation assays, respectively, as well as in vivo experiments employing a murine model of Schistosomiasis mansoni infection in BALB/c mice. The mean diameter and encapsulation efficiency of the nanosystems were as follows: SLN-SIB (252.8 ± 4.4 nm, 90.28 ± 2.2%), SLN-SIB-U (252.9 ± 14.4 nm, 77.05 ± 2.8%), and PN-SIB (241.8 ± 4.1 nm, 98.0 ± 0.2%). In the proliferation assay with the GRX cell line, SLN-SIB and SLN-SIB-U exhibited inhibitory effects of 43.09 ± 5.74% and 38.78 ± 3.78%, respectively, compared to PN-SIB, which showed no inhibitory effect. Moreover, SLN-SIB-U demonstrated a greater apparent permeability coefficient (25.82 ± 2.2) than PN-SIB (20.76 ± 0.1), which was twice as high as that of SLN-SIB (11.32 ± 4.6) and pure SIB (11.28 ± 0.2). These findings suggest that solid lipid nanosystems hold promise for further in vivo investigations. In the murine model of acute-phase Schistosomiasis mansoni infection, both SLN-SIB and SLN-SIB-U displayed hepatoprotective effects, as evidenced by lower alanine amino transferase values (22.89 ± 1.6 and 23.93 ± 2.4 U/L, respectively) than those in control groups I (29.55 ± 0.7 U/L) and I+SIB (34.29 ± 0.3 U/L). Among the prepared nanosystems, SLN-SIB-U emerges as a promising candidate for enhancing the pharmacokinetic properties of SIB.

2.
Curr Med Chem ; 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38310396

ABSTRACT

INTRODUCTION: Thrombotic disorders are among the leading causes of morbidity and mortality worldwide. Drugs used in the prevention and treatment of atherothrombosis have pharmacokinetic limitations and adverse effects such as hemorrhagic conditions, highlighting the importance of developing more effective antiplatelet agents. ethod: In this work, we synthesized N,N'-disubstituted ureas 3a-3j and evaluated their antiplatelet profiles through in vitro, ex vivo, and in silico studies. The synthesized derivatives exhibited a selective inhibitory profile against platelet aggregation induced by arachidonic acid (AA) in vitro, without significantly affecting other aspects of primary hemostasis and blood coagulation. The compounds that showed inhibition greater than 85% were submitted to the analysis of their potency by calculating the concentration required to inhibit 50% of platelet aggregation induced by AA (IC50). Urea derivative 3a was the most potent with IC50 of 1.45 µM. Interestingly, this derivative inhibited more than 90% of platelet aggregation induced by AA ex vivo, with a similar effect to acetylsalicylic acid. In the hemolysis assay, most of the urea derivatives presented values below 10% suggesting good hemocompatibility. Additionally, the compounds tested at 100 µM also showed no cytotoxic effects in HepG2 and Vero cells. RESULT: The in silico results suggested that compound 3a may bind to the key residue of COX-1 similar to AA and known COX-1 inhibitors, and the results are also in agreement with our SAR, which suggests that the inhibition of this enzyme is the most likely mechanism of antiplatelet activity. CONCLUSION: Therefore, these results demonstrated that N,N'-disubstituted ureas are promising candidates for the development of novel antiplatelet agents.

3.
Anim Reprod ; 20(4): e20230029, 2023.
Article in English | MEDLINE | ID: mdl-38148929

ABSTRACT

The risk of pregnancy loss in mares leads to the use of exogenous hormones to help pregnancy maintenance. The objective was to evaluate the proportion of thyroid hormones and steroids in neonates, in the following postpartum period, born to mares fed with synthetic progesterone and to verify the existence of a correlation between the level of progesterone between mother and neonate. Twenty-seven mares and their foals were used. The animals were divided into 5 experimental groups: group 1 (control, without hormonal supplementation), group 2 (random samples fed to 120 days of pregnancy with long-term progesterone), group 3 (mares fed with short-term progesterone as of 280.º day of pregnancy), group 4 (mares fed with long-term progesterone as of 280.º day of pregnancy) and group 5 (mares fed with synthetic hormone [altrenogest] as of 280.º day of pregnancy). The animal's blood collection took place immediately after parturition for the hormonal measurement. The hormones measured in neonates were total T3, free T4, TSH, progesterone and cortisone. In mares, only levels of progesterone. The groups of neonates showed no difference on levels of total T3, free T4, TSH and progesterone. There was no difference on levels of progesterone in mares among the groups. Neonates from groups 4 and 5 had higher and lower cortisone levels, respectively. No neonate showed clinical change. There was also no correlation between levels of progesterone in mares and foals. Thus, hormonal supplementation with long-term progesterone as of 280 days of pregnancy leds to an increase in the neonate's cortisone levels, in the meantime, supplementation with altrenogest as of 280 days of pregnancy caused a decrease on cortisone levels in foals, despite clinical signs have not been observed on these animals.

4.
Eur J Pharm Biopharm ; 190: 184-196, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37517449

ABSTRACT

Rivaroxaban (RVX), an oral direct factor Xa inhibitor, is being explored as an alternative to traditional anticoagulans. However, RVX still faces pharmacokinetic limitations and adverse effects, highlighting the need for more effective formulations. In this regard, pharmaceutical nanotechnology, particularly the use of polymeric nanoparticles (PNPs), offers a promising approach for optimizing RVX delivery. This study aimed to develop and physicochemically characterize RVX-loaded poly(lactic-co-glycolic acid) (PLGA)/sodium lauryl sulfate (SLS) or didodecyl dimethylammonium bromide (DMAB) nanoparticles, and also evaluate their pharmacological and toxicological profiles as a potential therapeutic strategy. The PNPs exhibited sizes below 300 nm and spherical morphology, with both negative and positive surface charges, according to surfactant used. They demonstrated high encapsulation efficiency and suitable yields, as well as rapid initial liberation followed by sustained release in different pH environments. Importantly, in vivo evaluations revealed a time-dependent antithrombotic effect surpassing the free form of RVX when administered orally in SLS or DMAB PNP. No hemolytic or cytotoxic effects were observed at various concentrations of the PNPs. Interestingly, the PNPs did not induce hemorrhagic events or cause liver enzyme alterations in vivo. These findings suggest that RVX-loaded SLS or DMAB PNPs are promising innovative therapeutic alternatives for the treatment of thromboembolic diseases.


Subject(s)
Nanoparticles , Polyglycolic Acid , Rats , Animals , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Rats, Wistar , Polyglycolic Acid/chemistry , Sodium Dodecyl Sulfate , Rivaroxaban , Bromides , Fibrinolytic Agents/pharmacology , Lactic Acid/chemistry , Glycols , Nanoparticles/chemistry , Particle Size
5.
Res Vet Sci ; 150: 107-114, 2022 Dec 05.
Article in English | MEDLINE | ID: mdl-35809414

ABSTRACT

Canine pituitary-dependent hypercortisolism (PDH) management with trilostane usually demands lifelong therapy. The greater the dose needed, the greater the risk of side effects. Selegiline therapy has been previously described but not commonly used for PDH treatment. The present work aimed to assess the efficacy of selegiline and trilostane combined therapy for canine PDH treatment. Fifteen client-owned dogs diagnosed with spontaneous PDH were enrolled. The patients were treated with trilostane (Tri group, n = 8, initial dose of 0.5 mg/kg, PO, q12h), or with trilostane and selegiline (Tri + Sel group, n = 7, initial trilostane dose of 0.5 mg/kg, PO, q12h and selegiline 1 mg/kg, PO, q24h). Dogs underwent clinical examination, serum biochemical analysis, urinalysis, abdominal ultrasound, and eACTH and post-ACTH cortisol measurements on treatment days zero (D0), 30 (D30), 90 (D90), and 180 (D180). There was a lack of adverse effects due to the combined therapy. Both groups showed a similar clinical response and lower post-ACTH cortisol levels at the study's end. There was no significant difference in trilostane dosage at D180 between groups. There was no documented increase in either right or left adrenal gland thickness in the Tri + Sel group in contrast with patients in the Tri group. However, there was no statistical difference between the groups regarding eACTH at D0 and D180. Patients in the Tri + Sel group achieved better serum triglycerides control at the end of the study. The association of selegiline with trilostane might be a feasible therapy for canine PDH; however, its eventual advantages need larger studies.


Subject(s)
Cushing Syndrome , Dog Diseases , Pituitary ACTH Hypersecretion , Adrenocorticotropic Hormone/therapeutic use , Animals , Cushing Syndrome/veterinary , Dihydrotestosterone/analogs & derivatives , Dog Diseases/drug therapy , Dogs , Hydrocortisone , Pilot Projects , Pituitary ACTH Hypersecretion/drug therapy , Pituitary ACTH Hypersecretion/veterinary , Selegiline/therapeutic use
6.
Int J Pharm ; 622: 121841, 2022 Jun 25.
Article in English | MEDLINE | ID: mdl-35623486

ABSTRACT

Several antithrombotic drugs are available to treat cardiovascular diseases due to its high mortality and morbidity worldwide. Despite these, severe adverse effects that can lead to treatment withdrawal have been described, highlighting the importance of new therapies. Thus, this work describes the development of fucoidan microparticles containing acetylsalicylic acid (MP/F4M) for pulmonary delivery and in vitro, ex vivo, and in vivo evaluation. Microparticles were prepared via spray-drying and characterized in vitro (mucoadhesive properties, coagulation time, platelet aggregation, adhesion, and hemolysis) followed by ex vivo platelet aggregation, in vivo arterial thrombosis, and hemorrhagic profile. The formulation physicochemical characterization showed suitable characteristics along with delayed drug release, increased breathable particle fraction, and high washability resistance as well as antiplatelet activity and enhanced platelet adhesion in vitro. In in vivo assays, MP/F4M protected against arterial thrombosis, without changes in the hemorrhagic profile. Finally, no lung changes were observed after prolonged pulmonary administration, whereas isolated ASA led to an inflammatory response. In conclusion, pulmonary administration of fucoidan microparticles with an antiplatelet drug may be an alternative therapy to treat cardiovascular diseases, opening the field for different formulations.


Subject(s)
Cardiovascular Diseases , Thrombosis , Aspirin , Humans , Platelet Aggregation Inhibitors/pharmacology , Polysaccharides , Thrombosis/drug therapy
7.
Top Companion Anim Med ; 49: 100648, 2022.
Article in English | MEDLINE | ID: mdl-35202848

ABSTRACT

Methylprednisolone acetate (MPA) is often prescribed to cats despite being recognized eventually as diabetogenic. To assess MPA-related insulin resistance and evaluate the efficacy of metformin or an obesity and diabetes mellitus (O&D) adjuvant diet as protective factors, a randomized clinical trial was conducted with 28 owned cats undergoing glucocorticoid therapy. A single MPA dose of 20 mg intramuscularly was administered to each cat. Controls (n = 10) received only MPA. In the diet group (n = 9), replacement of their habitual diet by ad-libitum feeding of a feline commercial O&D diet (Equilíbrio O&D, Total Alimentos ADM) was made. In the metformin group (n = 9), metformin chlorhydrate 25mg/cat PO/q24h was administered for 30 days. All patients were clinically evaluated at baseline (T0), day 15 (T15), and day 30 (T30) and blood draw for complete blood count, serum biochemistry, and determination of insulin concentrations. Fasting Insulin Sensitivity Index (SI), Amended Insulin to Glucose Ratio (AIGR), Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), and Homeostatic Model Assessment of beta-cell function (HOMA-B) were calculated based on fasting glycemia and insulinemia. All groups showed significantly higher levels (P < .05) of neutrophils, albumin, glucose, cholesterol, triglycerides, and serum insulin at T15. Patients in the metformin group showed also higher SI, AIGR, and HOMA-IR results at T15. Also, at T15, reduced levels (P < .05) of eosinophils, lymphocytes, and creatinine were documented in all groups. An MPA single dose induced changes in insulin sensitivity in cats; however, neither metformin nor O&D feeding used in this study was effective as protective factors against MPA-related insulin resistance.


Subject(s)
Cat Diseases , Insulin Resistance , Insulins , Metformin , Animals , Blood Glucose , Cat Diseases/drug therapy , Cat Diseases/prevention & control , Cats , Hypoglycemic Agents/therapeutic use , Insulin Resistance/physiology , Metformin/therapeutic use , Methylprednisolone Acetate
8.
Homeopathy ; 111(3): 164-175, 2022 08.
Article in English | MEDLINE | ID: mdl-34820794

ABSTRACT

BACKGROUND: Recent experimental results supporting the dynamization process show modification in the characteristics of solid mixtures. OBJECTIVE: The present work aims to evaluate the physicochemical properties of metallic zinc and lactose, evidencing the interactions between all chemical components presented in dynamized solid mixtures by analytical techniques. METHODS: Mixtures of zinc and lactose (1:9 w/w) were successively triturated at the same proportion according to the Brazilian Homeopathic Pharmacopoeia, receiving the designation of 10-1 - 10-6 (1dH - 6dH). All samples were submitted to the following characterization techniques: Atomic Absorption Spectrometry (AAS), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), and Raman Spectroscopy (RS). RESULTS: AAS results detected 97.0% of zinc in the raw material, and the triturated zinc lactose system (ZnMet) presented mean values similar to those expected for the physical mixtures: i.e., 9.94%, 1.23%, and 0.11% in the three first proportions (10-1, 10-2, 10-3), respectively. SEM images showed particle size reduction due to the trituration process. The XRD assays of ZnMet 10-3 and 10-6 indicated peak changes at 12.3° and 43.26°, probably associated with modifications of inter-atomic crystalline spacing. The thermal analysis results of dynamized samples suggest modifications in the chemical interaction between zinc and lactose induced by the physical forces applied. RS experiments showed variation in vibration frequencies due to the dynamization procedure, in which marked ZnMet 10-6 spectral modifications were detected at 357, 477, 1086 and 1142 cm-1, and in the wavelength range 860-920 cm-1. CONCLUSION: These results highlight the importance of applying suitable characterization methods to improve our understanding of the properties of homeopathic solid mixtures, whereas the uses of sensitive tools evidence the influence of trituration on the crystalline properties and in the enthalpy variation of dynamized samples.


Subject(s)
Homeopathy , Lactose , Calorimetry, Differential Scanning , Lactose/analysis , Thermogravimetry , Zinc
9.
J Med Primatol ; 50(2): 134-137, 2021 04.
Article in English | MEDLINE | ID: mdl-33432651

ABSTRACT

The study evaluated an echo-guided oocyte recovery technique in owl monkeys. Twelve females were selected for the transabdominal ovum retrieval technique. This procedure collected twenty-six follicles, of which nine oocytes were recovered, without harm to the animals. The technique is feasible and is a minimally invasive protocol for neotropical primates.


Subject(s)
Aotidae/physiology , Oocytes/physiology , Ultrasonography/methods , Animals , Female
10.
Nanotechnology ; 32(13): 135101, 2021 Mar 26.
Article in English | MEDLINE | ID: mdl-33276347

ABSTRACT

Rivaroxaban (RXB), an oral direct factor Xa inhibitor, presents innovative therapeutic profile. However, RXB has shown adverse effects, mainly due to pharmacokinetic limitations, highlighting the importance of developing more effective formulations. Therefore, this work aims at the preparation, physicochemical characterization and in vitro evaluation of time-dependent anticoagulant activity and toxicology profile of RXB-loaded poly(lactic-co-glycolic acid) (PLGA)/poloxamer nanoparticles (RXBNps). RXBNp were produced by nanoprecipitation method and physicochemical characteristics were evaluated. In vitro analysis of time-dependent anticoagulant activity was performed by prothrombin time test and toxicological profile was assessed by hemolysis and MTT reduction assays. The developed RXBNp present spherical morphology with average diameter of 205.5 ± 16.95 nm (PdI 0.096 ± 0.04), negative zeta potential (-26.28 ± 0.77 mV), entrapment efficiency of 91.35 ± 2.40%, yield of 41.81 ± 1.68% and 3.72 ± 0.07% of drug loading. Drug release was characterized by an initial fast release followed by a sustained release with 28.34 ± 2.82% of RXB available in 72 h. RXBNp showed an expressive time-dependent anticoagulant activity in human and rat blood plasma and non-toxic profile. Based on the results presented, it is possible to consider that RXBNp may be able to assist in the development of promising new therapies for treatment of thrombotic disorders.


Subject(s)
Anticoagulants/chemistry , Factor Xa Inhibitors/chemistry , Nanoparticles/chemistry , Poloxamer/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Rivaroxaban/chemistry , Animals , Anticoagulants/pharmacokinetics , Cell Survival , Chlorocebus aethiops , Drug Carriers/chemistry , Drug Liberation , Factor Xa Inhibitors/pharmacokinetics , Hemolysis , Humans , Nanoparticles/ultrastructure , Particle Size , Rats , Rivaroxaban/pharmacokinetics , Vero Cells
11.
J Tissue Eng Regen Med ; 14(12): 1792-1803, 2020 12.
Article in English | MEDLINE | ID: mdl-33010118

ABSTRACT

This study aimed to verify the efficacy of low-level laser irradiation (LLLI) on the proliferation of MC3T3-E1 preosteoblasts cultured on poly(lactic acid) (PLA) films. The produced films were characterized by contact angle tests, scanning electron microscopy (SEM), atomic force microscopy, differential scanning calorimetry, and X-ray diffraction. The MC3T3-E1 cells were cultured as three different groups: Control-cultured on polystyrene plastic surfaces; PLA-cultured on PLA films; and PLA + Laser-cultured on PLA films and submitted to laser irradiation (660 nm; 30 mW; 4 J/cm2 ). Cell proliferation was analyzed by Trypan blue and Alamar blue assays at 24, 48, and 72 h after irradiation. Cell viability was assessed by Live/Dead assay, apoptosis-related events were evaluated by Annexin V/propidium iodide (PI) expression, and cell cycle events were analyzed by flow cytometry. Cell morphology on the surface of films was assessed by SEM. Cell counting and biochemical assay results indicate that the PLA + Laser group exhibited higher proliferation (p < 0.01) when compared with the Control and PLA groups. The Live/Dead and Annexin/PI assays indicate increased cell viability in the PLA + Laser group that also presented a higher percentage of cells in the proliferative cell cycle phases (S and G2/M). These findings were also confirmed by the higher cell density observed in the irradiated group through SEM images. The evidence from this study supports the idea that LLLI increases the proliferation of MC3T3-E1 cells on PLA surfaces, suggesting that it can be potentially applied in bone tissue engineering.


Subject(s)
Low-Level Light Therapy , Osteoblasts/cytology , Osteoblasts/radiation effects , Polyesters/pharmacology , Animals , Apoptosis/drug effects , Apoptosis/radiation effects , Cell Cycle/drug effects , Cell Cycle/radiation effects , Cell Proliferation/drug effects , Cell Proliferation/radiation effects , Cell Shape/drug effects , Cell Shape/radiation effects , Cells, Cultured , Crystallization , Mice , Microscopy, Atomic Force , Osteoblasts/drug effects , X-Ray Diffraction
12.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 57(2): e167299, mai. 2020. tab, graf
Article in English | VETINDEX, LILACS | ID: biblio-1122175

ABSTRACT

The hypothalamus-pituitary-adrenal axis function may be impaired in patients with critical illnesses, especially cases of sepsis, named critical illness-related corticosteroid insufficiency (CIRCI). This study examined the function of the hypothalamic-pituitary-adrenal axis in normal dogs (n = 10) and dogs with critical diseases (n = 16), through determinations of endogenous ACTH (adrenocorticotropic hormone), basal cortisol and cortisol after stimulation in low doses of synthetic ACTH (1.0µg/kg/IV). The stimulation test with ACTH dose tested was verified as effective for evaluation of adrenal function in healthy and sick dogs. Ill dogs differed from healthy dogs by presenting higher basal cortisol values. Eight sick dogs presented a decrease in endogenous ACTH, basal cortisol, or Δ-cortisol. No significant differences were found between the control groups and critically ill dogs for the values of endogenous ACTH, cortisol after stimulation or Δ-cortisol. We concluded that the stimulation test with low-dose ACTH was effective for evaluation of adrenal function, as well as the fact that a considerable portion of critically ill dogs studied here, especially with sepsis, had evidence of inadequate corticosteroid response to stress.(AU)


A função do eixo hipotálamo-hipófise-adrenal pode estar comprometida em pacientes com doenças críticas, em especial casos de sepse, sendo nomeada de Insuficiência Corticosteroide Relacionada à Doença Crítica (ICRDC). O presente trabalho analisou a função do eixo hipotálamo-hipófise-adrenal em cães normais (n=10) e cães portadores de doenças críticas (n=16), por meio de determinações de ACTH (hormônio adrenocorticotrófico) endógeno, de cortisol basal e de cortisol após estímulo com baixa dose de ACTH sintético (1,0µg/kg/IV). Constatou-se que o teste de estimulação com ACTH na dose testada se mostrou eficaz para avaliação da função adrenal em cães sadios e doentes. Os cães doentes diferiram dos sadios ao apresentar valores maiores de cortisol basal. Oito cães doentes apresentaram diminuição do ACTH endógeno, do cortisol basal ou do Δ-cortisol. Não foram encontradas diferenças significativas entre os grupos Controle e Criticamente enfermos para os valores de ACTH endógeno, cortisol após estimulação ou Δ-cortisol. Concluiu-se que o teste de estimulação com baixa dose de ACTH mostrou-se eficaz para avaliação da função adrenal, assim como, uma parcela considerável da população de cães críticos aqui estudados, em especial com sepse, apresentaram evidências de resposta corticosteroide inadequada frente ao estresse.(AU)


Subject(s)
Animals , Dogs , Cosyntropin/administration & dosage , Adrenocorticotropic Hormone , Sepsis/complications , Glucocorticoids/therapeutic use , Hypothalamo-Hypophyseal System/physiopathology , Catastrophic Illness
13.
J Med Primatol ; 2018 Apr 25.
Article in English | MEDLINE | ID: mdl-29693261

ABSTRACT

BACKGROUND: The advent of non-invasive methods provides a powerful alternative to stress studies as the use of stressful handling techniques is no longer needed. However, many factors influence hormone metabolism such as sex, diet, and metabolic rate. Thus, validation should be species- and matrix-specific. METHODS: To assess stress response in brown howler monkeys Alouatta clamitans, we adopted an ACTH challenge test and parallelism to provide physiological and laboratorial validation. Radioimmunoassay was used to measure fecal levels of corticosterone. RESULTS AND CONCLUSIONS: All challenged animals presented a peak in fecal glucocorticoids levels the day after the treatment, while control animals did not. There were no significant sex differences, but females with infants had higher levels of corticosterone. Corticosterone levels showed parallelism to the standard curve of the diagnostics kit. Collectively, the data suggest that the method was validated and is useful for monitoring stress, thereby helping in conservation programs both in captivity and in the wild. Transit time information may be coupled with travel distance in seed dispersal studies.

14.
Theriogenology ; 84(4): 575-82, 2015 Sep 01.
Article in English | MEDLINE | ID: mdl-26001599

ABSTRACT

The goal of this study was to optimize an ovulation induction protocol for use with artificial insemination in the southern tigrina (Leopardus guttulus). The specific aims were to report the efficacy of using altrenogest, an oral progestin (Regumate, MSD Animal Health, Merck Animal Health), to suppress ovarian activity and prevent follicular hyperstimulation and hyperestrogenism after the administration of exogenous eCG and hCG. To monitor ovarian responses, fecal estrogen and progestogen metabolites were quantified by enzyme immunoassay in females before and after intramuscular administration of 200-IU eCG and 150-IU hCG in two trials, 4 months apart. During the first trial, there was no use of altrenogest, only the eCG-hCG ovulation induction protocol. In the second trial, the ovulation induction protocol was preceded by the administration of oral altrenogest for 14 days (minimum of 0.192 mg per kg per day). Altrenogest administration resulted in a suppression of follicular activity in three out of six females before eCG-hCG administration on the basis of lower mean estrogen concentrations (P < 0.05). It also resulted in four out of six females presenting lower fecal estrogen metabolite concentrations (P < 0.05) after ovulation induction, and two out of six individuals showed a reduction (P < 0.05) in postovulatory fecal progestogen metabolite concentrations, all when compared to the same female's cycles without the progestin. Fecal estrogen metabolite concentrations were closer to baseline in 50% of these individuals after altrenogest and eCG-hCG treatments when compared to basal concentrations before gonadotropins without the use of altrenogest. This study reported that use of altrenogest in southern tigrina can suppress ovarian activity and avoid hyperestrogenism after administration of eCG and hCG treatment. However, not all females responded uniformly, so more studies are needed to increase the efficacy of ovulation induction for use with artificial insemination in this species.


Subject(s)
Chorionic Gonadotropin/pharmacology , Felidae/physiology , Insemination, Artificial/veterinary , Ovulation Induction/veterinary , Trenbolone Acetate/analogs & derivatives , Animals , Chorionic Gonadotropin/administration & dosage , Estradiol/chemistry , Estradiol/metabolism , Feces/chemistry , Female , Progestins/chemistry , Progestins/metabolism , Species Specificity , Trenbolone Acetate/pharmacology
15.
Pesqui. vet. bras ; 35(1): 62-66, 01/2015. graf
Article in English | LILACS | ID: lil-746563

ABSTRACT

The influence of stress in an environment, according with the behavioral and endocrine variables of primates, are increasingly being studied by a diversity of authors, and have shown that abnormal behaviors associated with increased glucocorticoids may be directly related with the impairment of their well-being. In this work were used 22 adult chimpanzees (Pan troglodytes), 11 males and 11 females, kept in captivity in three different institutions. All animals had their behavior registered by focal session using a 30 seconds sample interval, during six months, totaling 4,800 registries per each animal. During this period, fecal samples were collected 3 times a week for the extraction and measurement of the concentration of fecal metabolites of glucocorticoid by radioimmunoassay. Of the total observed, stereotypical behaviors represented 13,45±2.76%, and among them, self-mutilation represented 38.28±3.98 %. The animals were classified into three different scores, according with the percentage of body surface with alopecia due to self-mutilation. It was found a positive correlation of high intensity between the scores of alopecia due to the observed mutilation and the average concentrations of fecal metabolites of glucocorticoids. This result strongly suggests that this measurement of self-mutilation in a chimpanzee can be used as an important auxiliary tool to evaluate de conditions of adaptation of an animal in captivity, functioning as a direct indicator of the presence of chronic stress...


A influência do estresse de um ambiente nas variáveis endócrino-comportamentais de primatas vem sendo cada vez mais estudada por diversos autores, e mostram que comportamentos anormais associados a aumentos de glicocorticóides podem estar diretamente relacionados ao comprometimento do bem-estar. Neste trabalho foram utilizados 22 chimpanzés (Pan troglodytes) adultos, sendo 11 machos e 11 fêmeas mantidos em cativeiro de três instituições diferentes. Todos os animais tiveram seus comportamentos registrados pelo método de amostragem focal por intervalo de tempo, durante seis meses, totalizando 4800 registros para cada animal. Amostras fecais foram coletadas três vezes por semana, durante este período, para extração e dosagem de metabólitos fecais de glicocorticoides por radioimunoensaio. Os comportamentos estereotipados representaram 13,45+2,76% do total observado, sendo que dentre estes comportamentos a automutilação representou 38,28+3,98%. Os animais foram classificados em três graus diferentes, de acordo com o percentual da superfície corpórea com alopecia decorrente da automutilação. Foi encontrada uma correlação positiva de intensidade forte entre os graus de alopecia decorrentes de mutilação observados e as médias de concentrações de metabólitos fecais de glicocorticoides. Este resultado sugere fortemente que esta graduação de automutilação de um chimpanzé possa ser utilizada como uma ferramenta auxiliar importante nas avaliações das condições de adaptação do animal ao cativeiro, atuando como um indicador indireto da presença de estresse crônico...


Subject(s)
Animals , Self Mutilation/diagnosis , Feces/chemistry , Glucocorticoids/isolation & purification , Pan troglodytes/metabolism , Adjustment Disorders , Animals, Zoo , Alopecia/veterinary , Stress, Physiological
16.
Braz. j. vet. res. anim. sci ; 49(4): 269-276, 2012.
Article in Portuguese | LILACS | ID: lil-687622

ABSTRACT

Vários autores enfatizaram a importância do monitoramento do ciclo estral em cadelas e citaram exemplos de como realizar tal procedimento. O objetivo deste estudo foiavaliar a técnica de dosagem de progesterona salivarem cadelas para identificar a ovulação nesta espécie. Para composição do grupo experimental, foram utilizadas 13 cadelas, de diferentes raças (sem raça definida, Buldogue Inglês, Bernesse Mountain Dog) e diferentes idades (11 meses a 9 anos). Amostras de sangue e saliva foram colhidas simultaneamente em todos os animais, a partir dos primeiros sinais clínicos de proestro. Amostras salivares foram obtidas com o uso de dispositivo comercial específico (Salivette®). Este método foi eficaz, visto ter tornado possível obter volume suficiente para dosagem de progesterona na grande maioria das amostras (100 μL para dosagens em duplicata). As concentrações de progesterona no soro foram determinadas pela técnica de radioimunoensaio e na saliva por enzimaimunoensaio, ambas com kits comerciais. Observou-se uma relação linear crescente e positiva entre a progesterona sérica e salivar (r=0,704; p<0,0001) em cadelas. Uma das cadelas apresentou ciclo anovulatório, no qual, durante 13 dias, as concentrações séricas de progesterona sérica se mantiveram entre 1,67 e 3,76 ng/mL e as concentrações salivares de progesterona entre 19,55 e 236,77 pg/mL. Conclui-se que as concentrações de progesterona salivarmensuradas pela técnica de enzimaimunoensaio podem ser utilizadas para avaliar a ocorrência ou ausência de ovulação em cadelas.


Several authors have emphasized the importance of monitoring estrous cycle in bitches and mentioned technique examples of how it can be done. The aim of this study was to evaluate the salivary progesterone quantification technique in order to identify ovulation in this species. To compound the experimental group, 13 bitches of different breeds (no specific breed, English Bulldog, Bernesse Mountain Dog)and different ages (from 11 months to 9 years old) were used. Blood and saliva samples were collected simultaneously in all animals, starting about the first day of proestrus clinical signs. Salivary samples were collected with a specific commercial device (Salivette®). This method was effective, since it has become possible to obtain enough volume in almost all samples to quantify salivary progesterone (100 μL for duplicate quantification). Serum progesterone was quantified by radioimmunoassay and salivary progesterone by enzyme immunoassay, both of them with commercial kits. There was an increasing, linear and positive correlation between salivary and serum progesterone (r=0.704; p<0.0001) in bitches. One of the animals had an anovulatory cycle, in which, for 13 days, seric progesterone levels were maintained between 1.67 and 3.76 ng/mL and salivary progesterone levels were maintained between 19.55 and 236.77 pg/mL. It was concluded that salivary progesterone levels measured by enzyme immunoassay is a technique that can be used to evaluate the presence or absence of ovulation in bitches.


Subject(s)
Animals , Dogs/classification , Progesterone/chemistry , Reproduction/physiology , Proestrus/physiology
17.
Braz. j. vet. res. anim. sci ; 49(6): 493-499, 2012.
Article in English | LILACS | ID: lil-687644

ABSTRACT

The aim of this prospective randomized clinical study was to compare blood glucose and cortisol levels between horses receiving xylazine and detomidine for surgical and non-surgical procedures. Horses from non-surgical groups received 0.5 mg/kg of xylazine (GX group, n=5) or 0.01 mg/kg of detomidine (GD group, n=5) for gastroscopic examination. Horses from the surgical groups received similar doses of xylazine (AX group, n=7) or detomidine (AD group, n=7), followed by anesthetic induction with 2 mg/kg of ketamine and 0.05 mg/kg of diazepam for an arthroscopic procedure under isoflurane anesthesia. Blood samples were obtained prior to the alpha-2 agonist administration (baseline) and after 10, 30, 60 and 90 minutes. All groups had a significant increase in blood glucose from 30 to 90 minutes after alpha-2 agonist administration, compared to baseline. After receiving the alpha-2 agonist, the AD group had blood glucose levels (118-150 mg/dL) significantly higher than GD (99-119 mg/dL) and AX (97-116 mg/dL) groups. Cortisol had no significant changes within a group. However, the AX group had cortisol levels (3.6-3.7 mg/dL) significantly lower than GX group (5.4-5.7 mg/dL) from 30 to 90 minutes after xylazine administration. We concluded that blood glucose levels were when detomidine was administered for surgical procedure, compared to xylazine also for surgical procedure, and non-surgical procedure. Serum cortisol was minimally affected by administration of xylazine and detomidine regardless procedures were surgical or non-surgical.


O objetivo deste estudo clínico, radomizado e prospectivo, foi comparar as concentrações sanguíneas de glicose e cortisol entre equinos recebendo xilazina e detomidina para procedimentos cirúrgicos e não-cirúrgicos. Os equinos dos grupos nãocirúrgicos receberam 0,5 mg/kg de xilazina (grupo GX, n=5) ou 0,01 mg/kg de detomidina (grupo GD, n=5) para realização de exame gastroscópico. Os equinos dos grupos cirúrgicos receberam doses semelhantes de xilazina (grupo AX, n=7) ou detomidina (grupo AD, n=7), seguindo-se a indução anestésica com 2 mg/kg de cetamina e 0,05 mg/kg de diazepam para realização de procedimento artroscópico durante anestesia com isofluorano. As amostras de sangue foram coletadas antes da administração do alfa-2 agonista (basal) e após 10, 30, 60 e 90 minutos. Todos os grupos tiveram um aumento significativo da glicemia, a partir de 30 até 90 minutos da administração do alfa-2 agonista, em relação ao basal. Após receber o alfa-2 agonista, o grupo AD apresentou glicemia (118-150 mg/dL) significativamente maior que os grupos GD (99-119 mg/dL) e AX (97-116 mg/dL). Não houve diferenças significativas da concentração de cortisol dentro de cada grupo. Entretanto, o grupo AX apresentou níveis de cortisol (3,6-3,7 mg/dL) significativamente mais baixos que o grupo GX (5,4-5,7 mg/dL), a partir de 30 até 90 minutos da administração de xilazina. Concluímos que a glicemia apresentou valor mais elevadoapós a administração de detomidina para realização de procedimento cirúrgico, comparado à xilazina administrada também para procedimento cirúrgico, e para procedimento não-cirúrgico. A concentração sérica de cortisol foi minimamente influenciada pela administração de xilazina e detomidina independentemente dos procedimentos serem cirúrgicos ou não-cirúrgicos.


Subject(s)
Animals , Blood Glucose/analysis , Glucose/analysis , Hydrocortisone/analysis , Arthroscopy , Horses/classification , Critical Pathways
18.
Pesqui. vet. bras ; 31(8): 677-682, ago. 2011. ilus, graf, tab
Article in Portuguese | LILACS | ID: lil-602154

ABSTRACT

A osteocondrose é uma das doenças ortopédicas do desenvolvimento mais comuns em cavalos, e deve ser encarada como uma desordem multifatorial. Caracteriza-se por ser uma doença dinâmica, onde o processo de reparo inicia-se quase que imediatamente após a formação da lesão osteocondral. A intensidade e eficácia deste reparo são fortemente relacionados à idade, e estão associados a reposição dos componentes da matriz cartilagínea. Uma vez que o fator de crescimento tipo insulina-1 (IGF-1) age regulando o crescimento da cartilagem articular, este estudo objetivou descrever os níveis séricos de IGF-I, insulina e glicose em potros Puro Sangue Lusitano hígidos ou com osteocondrose, desde o nascimento até 18 meses de idade. Dos potros acompanhados, 76,08 por cento apresentaram sinais radiográficos de osteocondrose com um mês de idade, porém somente 16,2 por cento mantiveram as lesões aos 18 meses. As concentrações de IGF-1 alcançaram picos entre 14 e 16 meses, equivalente ao início da puberdade. As concentrações de IGF-1 nos potros com osteocondrose foram menores que potros sadios, aos 2 e 5 meses (P<0,05), e os de insulina aos 2 meses (P<0,05). Em criatórios com alta ocorrência de osteocondrose recomenda-se que as mensurações dos níveis séricos de IGF-1 e insulina ocorram durante os primeiros 6 meses de idade, para que haja tempo hábil de se estabelecer medidas profiláticas e de tratamento.


Osteochondrosis is the most common orthopaedic developmental disorder in horses and has been traditionally defined as a multifactorial disease. The disease had a very dynamic character in which the repair process starts almost immediately after the lesion has formed. The intensity and efficacy of this repair process is strongly age-related and is determined by the turnover rate of the components of the extracellular matrix of the articular cartilage. Since the insulin-like growth factor-I (IGF-1) acts regulating the growth of articular cartilage, this study aimed to describe the serum levels of IGF-1, insulin and glucose in healthy Lusitano foals and foals with osteochondrosis, from birth to 18 months of age. At one month 76.08 percent of the foals showed radiographic signs of osteochondrosis, but at age of 18 months the percentage dropped to 16.2 percent. The IGF-1 concentrations reached peak values at age of 14 to 16 months, equivalent to the onset of puberty. The IGF-1 concentrations in foals with osteochondrosis were lower than in healthy 2 to 5-month-old foals (P<0.05), and the insulin at age of 2 months (P<0.05). On farms with high incidence of osteocondrosis is recommended that measurement of serum IGF-1 and insulin occur during the first 6 months of age, to have enough time to establish preventive and therapeutic measures.

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