RESUMO
Osteosarcoma (OSA) is the most common malignant bone cancer in children and dogs. The therapeutic protocols adopted for dogs and humans are very similar, involving surgical options such as amputation. Besides surgical options, radiotherapy and chemotherapy also are adopted. However, hematologic, gastrointestinal and renal toxicity may occur because of chemotherapy treatments. Recent study clearly showed that mesenchymal stem cells (MSCs) combined with recombinant human bone morphogenetic protein (rhBMP-2) may be associated with decreases of the tumorigenic potential of canine OSA. The aim of this study was to analyse the efficacy of chemotherapy with carboplatin and rhBMP-2 with MSCs in a canine OSA in vivo model. Canine OSA cells were implanted in mice Balb-c/nude with MSCs, rhBMP-2 and carboplatin. Flow cytometry and PCR for markers involved in tumour suppression pathways were analysed. Results showed that the combination of MSCs and rhBMP-2 reduced tumour mass and infiltration of neoplastic cells in tissues more efficiently than carboplatin alone. Thus it was demonstrated that the use of rhBMP-2 and MSCs, in combination with conventional antineoplastic, may be an efficient treatment strategy.
Assuntos
Antineoplásicos/uso terapêutico , Transplante de Medula Óssea/veterinária , Proteína Morfogenética Óssea 2/uso terapêutico , Neoplasias Ósseas/veterinária , Carboplatina/uso terapêutico , Doenças do Cão/terapia , Osteossarcoma/veterinária , Transplante de Células-Tronco/veterinária , Animais , Antineoplásicos/administração & dosagem , Transplante de Medula Óssea/métodos , Proteína Morfogenética Óssea 2/administração & dosagem , Neoplasias Ósseas/terapia , Carboplatina/administração & dosagem , Terapia Combinada/veterinária , Modelos Animais de Doenças , Cães , Feminino , Citometria de Fluxo/veterinária , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/terapia , Osteossarcoma/terapia , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes , Transplante de Células-Tronco/métodosRESUMO
The aim of this study was to compare plasma progesterone (P4) concentrations in nonlactating, multiparous Holstein cows (n = 24) treated with 2 types of intravaginal implants containing either 1.0 or 1.9 g of P4 either at the first use or during reuse of the implants after sanitizing the implant by autoclave or chemical disinfection. In a completely randomized design with a 2 × 3 factorial arrangement and 2 replicates, every cow underwent 2 of 6 treatments. Two sources of P4 [controlled internal drug release (1.9 g of P4) from Zoetis (São Paulo, Brazil), and Sincrogest (1.0 g of P4) from Ourofino (Cravinhos, Brazil)] and 3 types of processing, new (N), reused after autoclave (RA), and reused after chemical disinfection (RC), were used. After inducing luteolysis to avoid endogenous circulating P4, the cows were randomized in 1 of 6 treatments (1.9 g of N, 1.9 g of RA, 1.9 g of RC, 1.0 g of N, 1.0 g of RA, and 1.0 g RC). Cows were treated with the implants for 8 d and during this period blood samples were collected at 0, 2, 12, 24, 48, 72, 96, 120, 144, 168, and 192 h. Statistical analyses were performed using Proc-Mixed and the mean ± standard error of the mean P4 concentrations were calculated using the Proc-Means procedures of SAS 9.4 (SAS Institute Inc., Cary, NC). No interaction between treatments was observed. Comparing types of implant, average P4 concentrations during treatments were greater for 1.9 g than 1.0 g (1.46 vs. 1.14 ± 0.04 ng/mL). When types of processing were compared, average P4 concentrations did not differ between autoclaved and new inserts (1.46 vs. 1.37 ± 0.05 ng/mL; respectively), but both were greater than chemically disinfected implants (1.09 ± 0.04 ng/mL). Within 1.9-g P4 inserts, P4 concentrations from autoclaved implants were greater than new, which were greater than chemically disinfected (1.67 ± 0.06 vs. 1.49 ± 0.07 vs. 1.21 ± 0.05 ng/mL; respectively). For 1.0-g P4 implants, P4 concentrations from autoclaved did not differ from new, but both were greater than chemically disinfected (1.20 ± 0.08 vs. 1.24 ± 0.06 vs. 0.97 ± 0.05 ng/mL; respectively). In conclusion, the mean plasma P4 concentration in nonlactating Holstein cows was greater for 1.9 than 1.0 g of P4 and regardless of the type of implant, the autoclaving process provided greater circulating P4 in relation to chemical disinfection, and similar or greater P4 concentrations compared with a new implant.
Assuntos
Administração Intravaginal , Desinfecção/métodos , Sincronização do Estro/métodos , Progesterona/sangue , Animais , Brasil , Bovinos , Relação Dose-Resposta a Droga , Feminino , Distribuição AleatóriaRESUMO
This experiment aimed to compare circulating progesterone (P4), follicular dynamics, and fertility during reuse of intravaginal P4 implants that were sanitized by autoclave or chemical disinfection in lactating Holstein cows submitted to fixed-time artificial insemination (FTAI). For this, 123 primiparous and 226 multiparous cows from 2 farms, averaging (mean ± standard deviation) 163.9 ± 141.9 d in milk, 35.7 ± 11.3 kg of milk/d, and a body condition score of 2.9 ± 0.5, were enrolled in the study. Cows were randomly assigned to 1 of 2 treatments using a completely randomized design and each cow received a reused implant (1.9 g of P4; previously used for 8 d) that was either autoclaved (AUT; n = 177) or chemically disinfected (CHEM; n = 172) on d -10. Also on d -10, cows received 2 mg of estradiol benzoate and 100 µg of GnRH. On d -3, cows received 25 mg of dinoprost (PGF2α). A second PGF2α was given on d -2, along with 1 mg of estradiol cypionate and P4 implant removal. Cows received FTAI on d 0. A subset of cows (n = 143) was evaluated by ultrasound on d -10, -8, -6, -3, -2, 0, and 5 to identify ovarian structures, and blood was sampled on d -10, -3, and -2 for P4 concentrations by RIA. Pregnancy diagnoses were performed at d 32 and 60. Statistical analyses was performed using PROC-MIXED for continuous variables and PROC-GLIMMIX of SAS 9.4 (SAS Institute Inc., Cary, NC) for binomial variables. The treatments did not differ in circulating P4 on d -10 or -3, but P4 was greater on d -2 in CHEM cows. Ovulation to the treatments on d -10 was associated with lower circulating P4 on d -10 (2.0 vs. 3.1 ng/mL) and resulted in greater P4 on d -3 (4.0 vs. 2.4 ng/mL) and more cows with a corpus luteum on d -3 (100 vs. 40%) than nonovulating cows. Cows that ovulated to d -10 treatments were more likely to have a synchronized new follicular wave (97.9 vs. 63.2%) and had an earlier wave emergence (1.9 vs. 2.6 d), resulting in less cows ovulating a persistent follicle (0.0 vs. 35.7%). Type of P4 implant, corpus luteum presence on d -10, and ovulation to d -10 treatments did not affect fertility (pregnancy per AI; P/AI). However, P/AI on farm A was greater than on farm B at 32 (40.8 vs. 27.8%) and 60 d (35.8 vs. 24.3%), independent of treatment. In conclusion, P4 implants with different P4 release patterns did not produce detectable differences in follicular dynamics, synchronization rate, or P/AI. Nevertheless, presence of corpus luteum or ovulation at the beginning of the FTAI protocol affected reproductive variables, such as timing and synchronization of follicular wave emergence, and size of the ovulatory follicle. Beyond that, more overall synchronized cows became pregnant to the FTAI protocol.
Assuntos
Bovinos , Desinfecção/métodos , Implantes de Medicamento , Reutilização de Equipamento/veterinária , Sincronização do Estro , Fertilidade , Progesterona/administração & dosagem , Administração Intravaginal , Animais , Bovinos/sangue , Dinoprosta/administração & dosagem , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Sincronização do Estro/métodos , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Lactação , Leite , Folículo Ovariano/metabolismo , Ovulação , Gravidez , Progesterona/sangueRESUMO
Our objective was to evaluate the effect of a second PGF2α treatment (25 mg of dinoprost) or a double dose of PGF2α (50 mg of dinoprost) during a Resynch protocol on luteal regression and pregnancies per artificial insemination (P/AI) in lactating dairy cows. Lactating Holstein cows (n = 1,100) were randomly assigned at a nonpregnancy diagnosis to receive (1) Ovsynch (control: 100 µg of GnRH; 7 d, 25 mg of PGF2α; 56 h, 100 µg of GnRH), (2) Ovsynch with a second PGF2α treatment (GPPG: 100 µg of GnRH; 7 d, 25 mg of PGF2α; 24 h, 25 mg of PGF2α; 32 h, 100 µg of GnRH), or (3) Ovsynch with a double dose of PGF2α (GDDP: 100 µg of GnRH; 7 d, 50 mg of PGF2α; 56 h, 100 µg of GnRH). All cows received timed artificial insemination (TAI) approximately 16 h after the second GnRH treatment (G2). Pregnancy diagnosis was performed by transrectal palpation 39 ± 3 d after TAI, and pregnancy status was reconfirmed 66 d after TAI. Blood samples collected from a subset of cows in each treatment at the first PGF2α treatment (n = 394) and at G2 (n = 367) were assayed for progesterone (P4). Data were analyzed by logistic regression using the GLIMMIX procedure of SAS (SAS Institute Inc., Cary, NC). At 39 d after TAI, GPPG cows tended to have more P/AI than control cows [35% (137/387) vs. 31% (107/349)], whereas P/AI for GDDP cows [32% (118/364)] did not differ from that for control cows. Pregnancy loss from 38 to 66 d did not differ among treatments and was 8% (30/362). The percentage of cows with complete luteal regression (P4 <0.4 ng/mL at G2) tended to differ among treatments and was greater for GPPG cows than for GDDP and control cows (94% vs. 88% vs. 88%, respectively). Overall, cows with P4 <1 ng/mL at the first PGF2α treatment had fewer P/AI than cows with P4 ≥1 ng/mL (27% vs. 38%), whereas cows with P4 ≥0.4 ng/mL at G2 had fewer P/AI than cows with P4 <0.4 ng/mL (15% vs. 38%). We conclude that adding a second PGF2α treatment 24 h after the first within a Resynch protocol tended to increase the proportion of cows undergoing complete luteal regression and P/AI, whereas treatment with a double dose of PGF2α at a single time did not.
Assuntos
Bovinos/fisiologia , Dinoprosta/administração & dosagem , Sincronização do Estro/métodos , Fertilidade/efeitos dos fármacos , Luteólise/efeitos dos fármacos , Animais , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Inseminação Artificial/veterinária , Lactação , Masculino , Palpação , Gravidez , Progesterona/administração & dosagem , Fatores de TempoRESUMO
The selection of offspring from the desired sex can be one of the determining factors to increase the genetic progress and farmer ́s profitability in either beef or dairy cattle. In fact, the use of sex-sorted sperm has been applied worldwide combined with artificial insemination (AI) upon estrus detection in heifers. Additionally, several researches have been performed aiming to investigate the use of sex-sorted sperm during timed AI (TAI) programs and for insemination of superstimulated donors for in vivo embryo programs. Pregnancy per AI (P/AI) of cyclic heifers inseminated in estrus with sex-sorted sperm has been reported to be approximately 75 to 80% of the P/AI of heifers inseminated with non-sorted sperm. Insemination of superstimulated cows with sex-sorted sperm has been reported to reduce the production of viable embryos. Recently, however, it has been demonstrated that P/AI and embryo production per flushing resulting from AI with sex-sorted sperm may be improved when the time of AI is postponed in relation to the time of AI with non-sorted sperm. The P/AI of non stimulated females and fertilization rates and number of embryos recovered from superstimulated females were increased when AI occurred between 16 and 24 h after the onset of estrus (i.e. 6 to 14 h before ovulation). Nonetheless, despite the improvements achieved in the last decade, there is still a significant individual variability in fertility among bulls that have their sperm se x-sorted. It is critical that the pre-determination of the sire fertility is a paramount when sex-sorted sperm is utilized in commercial AI and ET programs. Thus, the aim of this review is to discuss the main concepts related to the use of sex-sorted sperm in TAI and ET programs, addressing some strategies to increase the efficiency of the technique.
Assuntos
Animais , Bovinos , Fertilidade/fisiologia , Inseminação Artificial/veterinária , Processos de Determinação Sexual , Taxa de GravidezRESUMO
The selection of offspring from the desired sex can be one of the determining factors to increase the genetic progress and farmer ́s profitability in either beef or dairy cattle. In fact, the use of sex-sorted sperm has been applied worldwide combined with artificial insemination (AI) upon estrus detection in heifers. Additionally, several researches have been performed aiming to investigate the use of sex-sorted sperm during timed AI (TAI) programs and for insemination of superstimulated donors for in vivo embryo programs. Pregnancy per AI (P/AI) of cyclic heifers inseminated in estrus with sex-sorted sperm has been reported to be approximately 75 to 80% of the P/AI of heifers inseminated with non-sorted sperm. Insemination of superstimulated cows with sex-sorted sperm has been reported to reduce the production of viable embryos. Recently, however, it has been demonstrated that P/AI and embryo production per flushing resulting from AI with sex-sorted sperm may be improved when the time of AI is postponed in relation to the time of AI with non-sorted sperm. The P/AI of non stimulated females and fertilization rates and number of embryos recovered from superstimulated females were increased when AI occurred between 16 and 24 h after the onset of estrus (i.e. 6 to 14 h before ovulation). Nonetheless, despite the improvements achieved in the last decade, there is still a significant individual variability in fertility among bulls that have their sperm se x-sorted. It is critical that the pre-determination of the sire fertility is a paramount when sex-sorted sperm is utilized in commercial AI and ET programs. Thus, the aim of this review is to discuss the main concepts related to the use of sex-sorted sperm in TAI and ET programs, addressing some strategies to increase the efficiency of the technique. (AU)
Assuntos
Animais , Bovinos , Processos de Determinação Sexual , Inseminação Artificial/veterinária , Fertilidade/fisiologia , Taxa de GravidezRESUMO
Diets can alter the concentrations of circulating hormones such as insulin and IGF_I. Such responsive hormones are related directly to nutritional status and moreover, directly or indirectly associated with reproductive function and fertility. Metabolic hormones are involved in follicular development, number and size of ovarian structure, circulating concetrations of steroid hormones duration of estrus, steroidogenesis, ovulation and embryonic development. Howeverm circulating metabolic hormones in excess, resulting from high dry matter/energy intake can also contribute to the reduction of oocytes and embryo quality. Although changes in dietary intake affect ovarian funciton in Bos taurus and Bos indicus cattle, it seems that overfeeding influences more profoundly oocytes/embryos from heifers and cows of Bos taurus than of Bos indicus breeds. There is also a distinct effect of nutrition on in vitro vs. in vivo embryo production, in which metabolic hormones seem to affect more the la ter stages of follicle development. Thus, this paper presents and discusses the results of some relevant studies on the role of feed intake and its association with metabolic hormones in mbovinemreproduction.
Assuntos
Animais , Esteroides , Fertilidade/fisiologia , Hormônios/biossíntese , Insulina/química , Bovinos/fisiologia , Embrião de Mamíferos/embriologiaRESUMO
Diets can alter the concentrations of circulating hormones such as insulin and IGF_I. Such responsive hormones are related directly to nutritional status and moreover, directly or indirectly associated with reproductive function and fertility. Metabolic hormones are involved in follicular development, number and size of ovarian structure, circulating concetrations of steroid hormones duration of estrus, steroidogenesis, ovulation and embryonic development. Howeverm circulating metabolic hormones in excess, resulting from high dry matter/energy intake can also contribute to the reduction of oocytes and embryo quality. Although changes in dietary intake affect ovarian funciton in Bos taurus and Bos indicus cattle, it seems that overfeeding influences more profoundly oocytes/embryos from heifers and cows of Bos taurus than of Bos indicus breeds. There is also a distinct effect of nutrition on in vitro vs. in vivo embryo production, in which metabolic hormones seem to affect more the la ter stages of follicle development. Thus, this paper presents and discusses the results of some relevant studies on the role of feed intake and its association with metabolic hormones in mbovinemreproduction.(AU)
Assuntos
Animais , Insulina/química , Hormônios/biossíntese , Fertilidade/fisiologia , Esteroides , Bovinos/fisiologia , Embrião de Mamíferos/embriologiaRESUMO
Reversed-phase packing materials were prepared from HPLC silica and from zirconized HPLC silica support particles having sorbed poly(methyloctylsiloxane) (PMOS) as the stationary phase. Portions of zirconized material were subjected to 80 kGy of ionizing radiation. Columns prepared from these packing materials were subjected to 5000 column volumes each of neutral and alkaline (pH 10) mobile phases, with periodic tests to evaluate chromatographic performance. It was shown that the PMOS stationary phase sorbed onto zirconized silica requires an immobilization treatment (such as gamma irradiation) for long term stability while prior surface zirconization of the silica support surface greatly improves the chromatographic stability of the stationary phase when using alkaline mobile phases.
Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Dióxido de Silício/química , Siloxanas/química , Radiação Ionizante , Silicatos/química , Zircônio/químicaRESUMO
An institution-based surveillance and nested case-control study was conducted in Natal, Northeastern Brazil to estimate the level and determinants of early neonatal mortality. The early neonatal mortality rate was 25.5 per 1000 live-birth, 75% of early neonatal deaths were premature low birthweight infants, and the mortality rates were 591 and 318 per 1000 respectively, for preterm small for gestational age (PT-SGA) and preterm appropriate for gestational age (PT-AGA) infants. Mortality was 50 per 1000 for term low birthweight, and 8.6 for term normal birthweight AGA infants. In addition to prematurity and low birthweight, the main risk factors associated with early neonatal death were maternal smoking, complications during pregnancy or intrapartum, and inadequate antenatal care. The associations were weaker for prepregnancy factors such as single marital status or low maternal body weight, and no significant associations were observed with socioeconomic status. These findings suggest that in this population, efforts to reduce early neonatal death should focus on improved maternal care and the prevention of prematurity.
PIP: To facilitate health service planning, a surveillance and case-control study were conducted of births in 3 hospitals and 2 maternity clinics in the city of Natal in northeastern Brazil. The surveillance study revealed 285 early neonatal deaths among the 111,171 singleton live births recorded in the study institutions from September 1984-February 1986, for a rate of 25.5/1000. 75% of these early neonatal deaths involved premature infants. The mortality rates were 591/1000 for preterm small-for-gestational age infants and 318/1000 for preterm appropriate-for-gestational age infants, while this rate was 50/1000 for term low-birthweight infants and only 8.6/1000 for term normal birthweights infants. The case-control study indicated that the maternal risk factors of body weight under 50 kg and single parent status significantly increased the likelihood of early neonatal mortality, while maternal age, parity, prior reproductive loss, and socioeconomic status did not have a significant effect on this outcome. Pregnancy-related factors that substantially increased the risk of early neonatal death included smoking, bleeding during the first or second trimester, toxemia, less than 5 prenatal care visits, and congenital malformations. These pregnancy-related risks exerted a more substantial effect than maternal characteristics, suggesting the feasibility of a strategy focused on preventing preterm births through prenatal care rather than a high-risk approach of screening women prior to pregnancy.