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1.
J Bone Miner Metab ; 42(3): 352-360, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38664255

RESUMO

INTRODUCTION: Trabecular bone score (TBS) estimates bone microstructure, which is directly measured by high-resolution peripheral quantitative computed tomography (HRpQCT). We evaluated the correlation between these methods and TBS influence on fracture risk assessed by FRAX. MATERIALS AND METHODS: We evaluated 129 individuals (82 women, 43 postmenopausal) 20 to 82.3 years without prevalent clinical or non-clinical morphometric vertebral fractures, using DXA (spine and hip), HR-pQCT at distal radius (R) and tibia (T) and TBS which classifies bone microarchitecture as normal (TBS ≥ 1.350), partially degraded (1.200 < TBS < 1.350), or degraded (TBS ≤ 1.200). RESULTS: Spine and hip BMD and HR-pQCT parameters at cortical bone: area (T), density (R,T) thickness (T) and trabecular bone: density (R,T), number (T) and thickness (R) were significantly better in the 78 individuals with normal TBS (group 1) versus the 51 classified as partially degraded (n = 42) or degraded microarchitecture (n = 9) altogether (group 2). TBS values correlated with age (r = - 0.55), positively with spine and hip BMD and all cortical and trabecular bone density and microstructure parameters evaluated, p < 0.05 all tests. Binary logistic regression defined age (p = 0.008) and cortical thickness (p = 0.018) as main influences on TBS, while ANCOVA demonstrated that HR-pQCT data corrected for age were not different between TBS groups 1 and 2. TBS adjustment increased FRAX risk for major osteoporotic fractures and hip fractures. CONCLUSION: We describe significant association between TBS and both trabecular and cortical bone parameters measured by HR-pQCT, consistent with TBS influence on fracture risk estimation by FRAX, including hip fractures, where cortical bone predominates.


Assuntos
Densidade Óssea , Osso Esponjoso , Osso Cortical , Tomografia Computadorizada por Raios X , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Osso Cortical/diagnóstico por imagem , Osso Esponjoso/diagnóstico por imagem , Masculino , Idoso de 80 Anos ou mais , Adulto , Absorciometria de Fóton , Adulto Jovem
2.
J Endocrinol Invest ; 44(3): 609-619, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32686043

RESUMO

PURPOSE: Data on endothelial derangements in patients with non-functioning adrenal incidentaloma (NFAI) are scarce. METHODS: We investigated if NFAI patients present clinical, biochemical and endothelial alterations compared to individuals without an adrenal lesion and also the associations among these variables. Forty-two NFAI and 40 controls were evaluated. NFAI diagnosis and controls were defined according to the current guidelines and based on a normal adrenal imaging exam, respectively. Body composition was evaluated by dual emission X-ray absorptiometry. Endothelial reactivity was assessed by two methods: tonometry (Endo-PAT®) and laser speckle contrast imaging (LSCI). RESULTS: There were no differences between groups regarding age, gender, ethnicity, smoking status, and statin use. The frequency of metabolic syndrome according to the International Diabetes Federation criteria was 69% and 57.9%, respectively in NFAI and controls (p = 0.36), whereas the atherosclerotic cardiovascular disease (ASCVD) risk was 63.4% and 66.7% (p = 0.81). The clinical, laboratory, and anthropometric characteristics, as well as body composition, were similar between the groups. Additionally, any differences between groups were observed on endothelial reactivity tests. Nevertheless, we noted an association between cortisol levels after 1 mg-dexamethosone suppression test (1 mg-DST) and the duration of post-occlusive reactive hyperemia tested on microcirculation (r = 0.30; p = 0.03). NFAI patients require more antihypertensive drugs to achieve blood pressure control (p = 0.04). The number of antihypertensive drugs used to control blood pressure correlated with cortisol levels after 1 mg-DST (r = 0.29; p = 0.03). CONCLUSIONS: Since both groups herein investigated had a high frequency of metabolic syndrome and ASCVD risk, it might explain similarities observed on endothelial reactivity. Nevertheless, prolonged reactive hyperemia response on microcirculation was correlated with cortisol levels under suppression.


Assuntos
Neoplasias das Glândulas Suprarrenais/complicações , Biomarcadores/sangue , Doenças Cardiovasculares/diagnóstico , Dexametasona/antagonistas & inibidores , Hidrocortisona/sangue , Hiperemia/diagnóstico , Síndrome Metabólica/diagnóstico , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Estudos Transversais , Feminino , Seguimentos , Humanos , Hiperemia/sangue , Hiperemia/etiologia , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/etiologia , Pessoa de Meia-Idade , Prognóstico
3.
J Dairy Sci ; 104(12): 12567-12579, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34531050

RESUMO

Development and health during calfhood are paramount for the success of dairy operations because they are associated with longevity and productivity later in life. Thus, provision of nutritional supplements has been explored as an alternative to improve growth of preweaned calves. Holstein calves (female = 472, male = 46) from 2 dairies located in the San Joaquin Valley were assigned randomly to receive 25 g/d of Gammulin (APC Inc.) from 2 to 24 d of age (GAM = 263) or to receive no supplementation (control = 255). Calves were fed a mixture of waste milk and milk replacer (3.79 L/d), and study personnel added the supplement to the bottles of calves in the GAM treatment daily. Study personnel monitored calves 6 d/wk and recorded starter intake, fecal score (1 = firm, 4 = watery), and attitude score (1 = alert and responsive, 4 = recumbent). Blood samples were collected (4, 7, 14, 26, 44, 56, and 68 d of age) to determine concentrations of total protein, glucose (n = 64), nonesterified fatty acids (n = 64), ß-hydroxybutyrate (n = 171), and hematocrit (n = 518). Calves (n = 64) were treated with 0.5 mg of ovalbumin at 3, 21, and 42 d of age, and concentration of anti-ovalbumin IgG was measured. The percentage of polymorphonuclear leukocytes positive for phagocytosis and oxidative burst after the ex vivo exposure to an enteropathogenic Escherichia coli was evaluated (n = 64). We followed the female calves through the end of the first lactation or until they left the herd to evaluate the effect of treatment on first-lactation performance. Treatment did not affect metabolic and immune responses. During the supplementation (1 to 24 d of age), starter intake did not differ between treatments, but the GAM treatment reduced starter intake (638.5 ± 1.1 vs. 696.6 ± 1.1 g/d; mean ± standard error of the mean) from 25 to 60 d of age and average daily gain (798.8 ± 15.4 and 749.5 ± 15.2) from 23 to 60 d of age, resulting in reduced body weight at 60 d of age (68.4 ± 0.4 vs. 69.8 ± 0.5 kg). From 1 to 24 d of age, GAM treatment reduced the number of days calves had fecal score = 4 (ratio of number of days = 0.92; 95% confidence interval = 0.84-1.00) and it reduced the number of electrolyte treatments calves received (ratio of number of treatments = 0.92; 95% confidence interval = 0.85-0.99). Treatment did not affect the hazard of first calving and first-lactation 305-d milk yield, but the adjusted hazard ratio (0.82; 95% confidence interval = 0.65, 1.04) of pregnancy in the first lactation tended to be reduced for the GAM treatment. In the conditions of this experiment, supplementation with 25 g/d of GAM to the liquid feed from 2 to 24 d of age did not improve calfhood health and performance.


Assuntos
Ração Animal , Dieta , Ração Animal/análise , Animais , Peso Corporal , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Lactação , Masculino , Leite , Gravidez , Desmame
4.
J Dairy Sci ; 104(12): 12816-12829, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34482979

RESUMO

Despite the rapid growth in popularity of the Jersey breed, most research on dairy cows in the United States has been done with the Holstein breed. Postpartum uterine diseases negatively influence reproductive performance of dairy cows and limited data are available regarding predisposing factors for uterine diseases in Jersey cows. Our objectives were to determine the prevalence and risk factors for purulent vaginal discharge (PVD) and its effect on fertility of lactating Jersey cows. This was a retrospective observational study with data collected from 3,822 Jersey cows. The Metricheck device was used for PVD diagnosis, and positive cases (≥50% of pus in exudate) were further classified for severity using the following 4 categories based on the amount of pus observed: 50 to 60% pus in exudate, 60 to 90% pus in exudate, 90 to 100% pus in exudate, and 90 to 100% pus in exudate + uterine fluid detected by palpation per rectum. Univariable and multivariable regression analyzes were conducted to dissect the risk factors for PVD and severity of PVD in Jerseys cows. The major risk factors for PVD were calving-related problems, retained fetal membrane, metritis, and days in the close-up diet. A subgroup of cows (n = 740) was scored for body condition and locomotion scores and had blood sampled in the peripartum for determination of plasma concentrations of nonesterified fatty acids and ß-hydroxybutyrate. In the multivariable analysis that considered data collected for the subgroup of cows, peripartum nonesterified fatty acids, postpartum ß-hydroxybutyrate, and peripartum locomotion and body condition scores were not retained in the reduced model of predictors of PVD. Not surprisingly, pregnancy per artificial insemination following the first and second services was reduced in cows diagnosed with PVD compared with cows without PVD. In addition, PVD was associated with increased odds of pregnancy loss after the first service and reduced hazard of pregnancy by 305 d in milk. The stratification of PVD severity according to the amount of pus observed and the consistency of the uterus was meaningful, as observed by the differences in reproductive outcomes between cows with diverging amounts of pus in the retrieved exudate. Risk factors for PVD in Jersey cows was similar to previously reported for Holstein cows, and a strong detrimental effect of PVD on fertility was also observed in Jersey cows.


Assuntos
Doenças dos Bovinos , Descarga Vaginal , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Feminino , Lactação , Gravidez , Reprodução , Fatores de Risco , Descarga Vaginal/veterinária
5.
J Endocrinol Invest ; 43(2): 163-171, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31392573

RESUMO

PURPOSE: Acromegaly is a cause of secondary osteoporosis and is associated with increased risk of vertebral fractures (VFs). The influence of exon 3-deleted isoform of growth hormone receptor (d3-GHR) on bone microarchitecture has not been studied in acromegaly. AIM: The aim of this study was to analyze the associations between d3-GHR isoform and bone mineral density (BMD), bone microarchitecture, and VFs in acromegaly patients. METHODS: Consecutive acromegaly patients treated at a single reference center were included. BMD was analyzed using dual-energy X-ray absorptiometry (DXA) and bone microarchitecture was analyzed by high-resolution peripheral quantitative computed tomography (HR-pQCT). The presence of moderate to severe VFs was assessed by thoracic and lumbar X-ray. GHR genotyping was analyzed by PCR, and full-length isoform of GHR (fl-GHR) was represented by a 935-bp fragment and d3-GHR by a 532-bp fragment. RESULTS: Eighty-nine patients were included [56 females; median age at diagnosis: 43 years (17-78)]. Disease was uncontrolled in 63% of patients. At least one d3-GHR allele was present in 60% of patients. Frequency of active disease (p = 0.276) and hypogonadism (p = 1.000) was not different between patients with fl-GHR and those with at least one d3-GHR. There was no difference in any DXA or HR-pQCT parameters between patients with fl-GHR and those with d3-GHR. Significant VFs were observed in 14% of patients, but there was no difference in frequency between patients with fl-GHR and those with at least one d3-GHR allele (p = 0.578). CONCLUSIONS: Presence of d3-GHR was not associated with worse BMD or bone microarchitecture or with higher frequency of significant VFs.


Assuntos
Acromegalia/diagnóstico por imagem , Acromegalia/genética , Densidade Óssea/genética , Éxons/genética , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/genética , Receptores da Somatotropina/genética , Absorciometria de Fóton/métodos , Acromegalia/sangue , Adolescente , Adulto , Idoso , Feminino , Fraturas Ósseas/sangue , Hormônio do Crescimento Humano/sangue , Hormônio do Crescimento Humano/genética , Humanos , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas/sangue , Receptores da Somatotropina/sangue , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
6.
J Endocrinol Invest ; 42(7): 797-807, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30465247

RESUMO

PURPOSE: Metabolic syndrome (MS) and sarcopenia are associated with increased cardiovascular risk. No studies using dual-energy x-ray absorptiometry (DXA) have evaluated association between body composition (BC) changes and MS in adrenal incidentaloma (AI). Our aim was to analyse BC in non-functioning AI (NFAI) and intermediate phenotype (IP) relative to controls and to correlate with cortisol levels. METHODS: Cross-sectional study with 44 NFAI (serum cortisol ≤ 50 nmol/L after the overnight 1 mg dexamethasone suppression test), 27 IP (cortisol 51-138 nmol/L), and 41 controls (normal adrenal on imaging examination) using DXA. Autonomic cortisol secretion (cortisol > 138 nmol/L) was excluded from the study. BC data were compared using criteria for MS (World Health Organization, National Cholesterol Education Program-Adult Treatment Panel-III, American Association of Clinical Endocrinologists (AACE), and International Diabetes Federation). RESULTS: There was no significant difference in clinical data and body mass index (BMI) among the three groups. Waist circumference (WC) was larger in AI vs. controls (p < 0.01). Waist-to-hip ratio was higher in NFAI vs. controls and waist-to-height ratio was higher in IP vs. controls (p = 0.03 and p = 0.02, respectively). The frequency of MS was higher in AI vs. controls. BC was not different among the groups. Patients with AI there was a significant association of MS with both an increase in total fat and body fat index (all criteria), and a significant difference between MS and smaller BMI-adjusted lean mass (AACE, p = 0.036). No correlation of cortisol after 1 mg dexamethasone test with BC or MS. AI and WC were independently associated with MS. CONCLUSIONS: AI presented high frequency of MS and was independently associated with MS. Possible deleterious effects of cortisol secretion seem to initially affect the muscular system.


Assuntos
Absorciometria de Fóton/métodos , Neoplasias das Glândulas Suprarrenais/complicações , Composição Corporal , Síndrome Metabólica/diagnóstico , Fenótipo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Síndrome Metabólica/etiologia , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
7.
J Dairy Sci ; 101(10): 9575-9590, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30100501

RESUMO

We hypothesized (1) that neither duration of the Ovsynch program nor dose frequency of PGF2α would change the proportion of cows with complete luteolysis (progesterone <0.4 ng/mL 72 h after PGF2α) and (2) that the additional GnRH treatment administered as part of a presynchronization program would not alter the proportion of anovulatory cows starting the timed artificial insemination (AI) program compared with an alternative shorter presynch program including only 1 GnRH treatment. Lactating Holstein cows (n = 406) were milked 3 times daily and enrolled in a 2 × 2 × 2 factorial experiment consisting of 8 treatments before the first postpartum AI. Treatments were used to test ovulatory, luteal, and luteolytic outcomes to 3 main effects: (1) 2 GnRH-PGF2α presynchronization programs (PG-3-G vs. Double Ovsynch), (2) 2 Ovsynch program durations [5 d: GnRH (GnRH-1)-5 d-PGF2α-24 h-PGF2α-32 h-GnRH (GnRH-2)-16 h-timed AI; 7 d: GnRH-1-7 d-PGF2α-56 h-GnRH-2-16 h-timed AI], and (3) 2 PGF2α dose frequency treatments (2 × 25 mg) 24 h apart versus 1 dose (1 × 50 mg) of PGF2α administered 72 h before timed AI. The presynchronization treatments of PG-3-G and Double Ovsynch had no effect on the proportion of cows with luteal function at the onset of the Ovsynch treatments (87.9 vs. 86.2%). Although ovulatory responses were similar after GnRH-1 (>60%), Double Ovsynch cows tended to have greater ovulatory responses than PG-3-G after GnRH-2 (95.3 vs. 90.6%). The 2 × 25-mg doses of PGF2α and the 1 × 50-mg dose induced luteolysis in both Ovsynch treatment durations, but the 1 × 50-mg dose was less effective in the 5-d program. More pregnancy per AI (P/AI; 49.2%) tended to occur in the PG-3-G cows in the 7-d program compared with the other treatment combinations (range: 32.4-37.4%; Ovsynch × presynch interaction). In addition, an Ovsynch × PGF2α dose frequency interaction resulted in cows receiving the 1 × 50-mg dose in the 7-d program having the greatest P/AI (46.1%) and cows receiving the 1 × 50-mg dose in the 5-d program having the least P/AI (30.6%). We conclude that complete luteolysis was less effective in the 5-d program when the 1 × 50-mg dose was applied, but both PGF2α dose frequencies (1 × 50 mg and 2 × 25 mg 24 h apart) effectively induced complete luteolysis in the 7-d program. Treatments producing complete luteolysis tended to be related to subsequent pregnancy outcomes.


Assuntos
Bovinos/fisiologia , Dinoprosta/farmacologia , Sincronização do Estro/métodos , Luteólise/efeitos dos fármacos , Ovulação/fisiologia , Animais , Dinoprosta/administração & dosagem , Feminino , Fertilidade , Hormônio Liberador de Gonadotropina , Inseminação Artificial , Lactação , Luteólise/fisiologia , Gravidez , Progesterona
8.
J Dairy Sci ; 100(1): 807-820, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27889121

RESUMO

Using an activity monitoring system (AMS) equipped with an accelerometer, 2 experiments were conducted to test the hypotheses that (1) enhancing progesterone before inducing luteolysis or (2) exposing cows to estradiol cypionate (ECP) or testosterone propionate (TP) after luteolysis would increase occurrence and intensity of estrus. Our goal was to determine if more cows could be detected in estrus by an AMS compared with other estrus-detection aids. In experiment 1, cows (n=154) were fitted with both an AMS collar and a pressure-sensitive, rump-mounted device (HeatWatch; HW) and assigned to 3 treatments: (1) no CL + progesterone insert (CIDR) for 5d, (2) CL only, or (3) CL + 2 CIDR inserts for 5d to achieve a range in concentrations of progesterone. Prostaglandin F2α was administered to all cows upon CIDR insert removal or its equivalent. Progesterone concentration up to 72h posttreatment was greatest in CL + 2 CIDR, followed by CL only, and no CL + CIDR cows. Estrus occurred 14 to 28h earlier in no CL + CIDR compared with CL-bearing cows. Estrus intensity was greater for CL + 2 CIDR than for CL-only cows. The AMS and HW detected 70 and 59% of cows defined to be in estrus, respectively. In experiment 2, cows (n=203) were equipped with both an AMS and a friction-activated, rump-mounted patch (Estrotect patch) and assigned to receive 1mg of ECP, 2mg of TP, or control 24h after PGF2α. Concentrations of estradiol 24 and 48h after treatment were greater in ECP cows compared with controls. Estrus expression detected by AMS or patches in cows defined to be in estrus tended to be greater or was greater for ECP compared with controls, respectively. Compared with controls and in response to TP or ECP, estrus occurred 8 to 18h earlier and was of greater intensity for ECP cows, respectively. The AMS and patches determined 73 and 76% of cows defined to be in estrus, respectively. Of cows exposed to the AMS, HW, or patches, 70, 61, and 75%, respectively, were detected in estrus and more than 93% of these subsequently ovulated. In contrast, of the residual cows not detected in estrus, 62 to 77% ovulated in the absence of detected estrus. Only ECP was successful in inducing more expression and intensity of estrus, and proportions of cows detected in estrus exceeded 80%. Given the large proportion of cows equipped with AMS collars ovulating in the absence of estrus, further research is warranted to determine if more pregnancies can be achieved by inseminating those cows not detected in estrus at an appropriate time when PGF2α is administered to induce luteolysis.


Assuntos
Estro/efeitos dos fármacos , Lactação , Animais , Bovinos , Dinoprosta/farmacologia , Estradiol/análogos & derivados , Estradiol/farmacologia , Detecção do Estro , Feminino , Luteólise/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Progesterona/metabolismo , Propionato de Testosterona/farmacologia
9.
Horm Metab Res ; 48(12): 854-861, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27756093

RESUMO

Neuromedin B (NB) and gastrin-releasing peptide (GRP) are bombesin-like peptides, found in the gastrointestinal tube and pancreas, among other tissues. Consistent data proposed that GRP stimulates insulin secretion, acting directly in pancreatic cells or in the release of gastrointestinal hormones that are incretins. However, the role of NB remains unclear. We examined the glucose homeostasis in mice with deletion of NB receptor (NBR-KO). Female NBR-KO exhibited similar fasting basal glucose with lower insulinemia (48.4%) and lower homeostasis model assessment of insulin resistance index (50.5%) than wild type (WT). Additionally, they were more tolerant to oral glucose, demonstrated by a decrease in the area under the glucose curve (18%). In addition, 15 min after an oral glucose load, female and male NBR-KO showed lower insulin serum levels (45.6 and 26.8%, respectively) than WT, even though blood glucose rose to similar levels in both groups. Single injection of NB, one hour before the oral glucose administration, tended to induce higher serum insulin in WT (28.9%, p=0.3), however the same did not occur in NBR-KO. They showed no changes in fasting insulin content in pancreatic islets by immunohistochemistry, however, the fasting serum levels of glucagon-like peptide, a potent incretin, exhibited a strong trend to reduction (40%, p=0.07). Collectively, mice with deletion of NB receptor have lower insulinemia, especially in response to oral glucose, and females also exhibited a better glucose tolerance, suggesting the involvement of NB and its receptor in regulation of insulin secretion induced by incretins, and also, in insulin sensitivity.


Assuntos
Deleção de Genes , Glucose/administração & dosagem , Glucose/farmacologia , Insulina/metabolismo , Receptores da Bombesina/metabolismo , Administração Oral , Animais , Jejum , Feminino , Glucagon/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Teste de Tolerância a Glucose , Homeostase/efeitos dos fármacos , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurocinina B/administração & dosagem , Neurocinina B/análogos & derivados , Neurocinina B/farmacologia , Receptores da Bombesina/deficiência
10.
J Dairy Sci ; 99(9): 7612-7623, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27289155

RESUMO

The objectives of the experiments were to compare ovarian responses, pregnancy per artificial insemination, and pattern of insemination of 2 estrus detection-based presynchronization protocols before first artificial insemination (AI) during heat stress. In experiment 1, primiparous lactating dairy cows (n=1,358) from 3 dairies were assigned randomly to 2 treatments at 60±3 (±SD) DIM (study d 0): (1) treatment with 100 µg of GnRH on study d 0 (Gpresynch), or (2) no treatment on study d 0 (control). In experiment 2, multiparous lactating dairy cows (n=1,971) from 3 dairies were assigned randomly to 2 treatments at 49±3 (±SD) DIM (study d 0), similar to experiment 1. In both experiments, PGF2α injections were administered 14 d apart starting on study d 7 for all cows. Cows not inseminated after detection of estrus were submitted to a timed artificial insemination protocol at study d 35. In a subgroup of cows from 2 dairies, concentrations of progesterone were determined from blood samples collected on study d 0 and 7. Furthermore, ovaries were examined by ultrasonography on study d -14, 0, and 7 to determine cyclic status and ovulation in response to GnRH treatment. In experiment 1, progesterone concentration was not different on d 0, but progesterone was increased for Gpresynch compared with control cows on study d 7 (3.6±0.3 vs. 2.7±0.4 ng/mL), respectively. Ovulation risk from study d 0 to 7 was increased for Gpresynch compared with control (50.6 vs. 15.2%). Control cows were inseminated at a faster rate than Gpresynch cows [adjusted hazard ratio (AHR)=0.89, 95% confidence interval=0.80 to 1.00], and the interaction between treatment and dairy affected pregnancy per artificial insemination at 36 and 94 d post-artificial insemination. In experiment 2, concentrations of progesterone did not differ on study d 0 or 7, despite ovulation risk from study d 0 to 7 being greater in Gpresynch than control cows (46.9 vs. 23.8%). The interaction between treatment and dairy affected hazard of insemination with Gpresynch cows from dairy 1 (AHR=1.21; 1.05 to 1.41) being inseminated faster than control cows. Hazard of pregnancy was affected by treatment because Gpresynch cows became pregnant at a faster rate than control cows (AHR=1.25; 1.04 to 1.50). In conclusion, GnRH-based presynchronization protocols initiated before the end of the voluntary waiting period may have benefits in reproductive efficiency of estrus detection-based programs during heat stress. In addition, treatment with GnRH decreased the prevalence of anovular cows at the initiation of PGF2α injections.


Assuntos
Bovinos/fisiologia , Detecção do Estro , Hormônio Liberador de Gonadotropina/farmacologia , Inseminação Artificial/veterinária , Animais , Sincronização do Estro , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Temperatura Alta , Gravidez , Distribuição Aleatória
11.
J Dairy Sci ; 99(1): 672-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26519977

RESUMO

Previous research has shown that postpartum administration of the nonsteroidal antiinflammatory drug (NSAID) sodium salicylate can increase 305-d milk yield in older dairy cattle (parity 3 and greater). However, in this prior work, sodium salicylate was delivered to cows via the drinking water, a method that does not align well with current grouping strategies on commercial dairy farms. The objective of the current study was to replicate these results on a commercial dairy farm with a simplified treatment protocol and to compare sodium salicylate with another NSAID, meloxicam. Dairy cattle in their second lactation and greater (n=51/treatment) were alternately assigned to 1 of 3 treatments at parturition, with treatments lasting for 3d. Experimental treatments began 12 to 36 h after parturition and were (1) 1 placebo bolus on the first day and 3 consecutive daily drenches of sodium salicylate (125 g/cow per day; SAL); (2) 1 bolus of meloxicam (675 mg/cow) and 3 drenches of an equal volume of water (MEL); or (3) 1 placebo bolus and 3 drenches of water (CON). Blood samples were collected on the first day of treatment, immediately following the last day of treatment, and 7d after the last day of treatment; plasma was analyzed for glucose, ß-hydroxybutyrate (BHB), free fatty acids, haptoglobin, and paraoxonase. Milk production, body condition score, reproductive status, and retention in the herd were monitored for 365 d posttreatment, and effects of treatment, parity, days in milk, and interactions were evaluated in mixed effects models. Significance was declared at P<0.05. Whole-lactation milk and protein yields were greater in NSAID-treated cows, although 305-d fat production was not affected. There was a significant interaction of treatment and parity for plasma glucose concentration; MEL increased plasma glucose concentrations compared with CON and SAL in older cows. Sodium salicylate decreased plasma BHB concentration compared with MEL at 7d posttreatment, although no difference was detected immediately following treatment. Haptoglobin concentrations were elevated in SAL cows compared with CON. There was a tendency for CON cows to be removed from the herd more quickly than MEL cows (42 vs. 26% at 365 d posttreatment). Body condition score, concentrations of plasma free fatty acids and paraoxonase, and time to pregnancy were not affected by treatment. These results indicate that NSAID administration in postpartum cows has the potential to be a viable way to improve productivity and potentially longevity in commercial dairies, although further research is necessary to optimize recommendations for producers.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Lactação/efeitos dos fármacos , Leite/metabolismo , Período Pós-Parto , Ácido 3-Hidroxibutírico/sangue , Animais , Arildialquilfosfatase/sangue , Glicemia/metabolismo , Bovinos , Ácidos Graxos não Esterificados/sangue , Feminino , Haptoglobinas/metabolismo , Reprodução/efeitos dos fármacos , Salicilato de Sódio/farmacologia
12.
Br J Sports Med ; 50(21): 1309-1314, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27445362

RESUMO

Injury prediction is one of the most challenging issues in sports and a key component for injury prevention. Sports injuries aetiology investigations have assumed a reductionist view in which a phenomenon has been simplified into units and analysed as the sum of its basic parts and causality has been seen in a linear and unidirectional way. This reductionist approach relies on correlation and regression analyses and, despite the vast effort to predict sports injuries, it has been limited in its ability to successfully identify predictive factors. The majority of human health conditions are complex. In this sense, the multifactorial complex nature of sports injuries arises not from the linear interaction between isolated and predictive factors, but from the complex interaction among a web of determinants. Thus, the aim of this conceptual paper was to propose a complex system model for sports injuries and to demonstrate how the implementation of complex system thinking may allow us to better address the complex nature of the sports injuries aetiology. According to this model, we should identify features that are hallmarks of complex systems, such as the pattern of relationships (interactions) among determinants, the regularities (profiles) that simultaneously characterise and constrain the phenomenon and the emerging pattern that arises from the complex web of determinants. In sports practice, this emerging pattern may be related to injury occurrence or adaptation. This novel view of preventive intervention relies on the identification of regularities or risk profile, moving from risk factors to risk pattern recognition.

13.
AAPS PharmSciTech ; 17(2): 252-61, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26040724

RESUMO

This work aimed at improving the solubility of curcumin by the preparation of spray-dried ternary solid dispersions containing Gelucire®50/13-Aerosil® and quantifying the resulting in vivo oral bioavailability and anti-inflammatory activity. The solid dispersion containing 40% of curcumin was characterised by calorimetry, infrared spectroscopy and X-ray powder diffraction. The solubility and dissolution rate of curcumin in aqueous HCl or phosphate buffer improved up to 3600- and 7.3-fold, respectively. Accelerated stability test demonstrated that the solid dispersion was stable for 9 months. The pharmacokinetic study showed a 5.5-fold increase in curcumin in rat blood plasma when compared to unprocessed curcumin. The solid dispersion also provided enhanced anti-inflammatory activity in rat paw oedema. Finally, the solid dispersion proposed here is a promising way to enhance curcumin bioavailability at an industrial pharmaceutical perspective, since its preparation applies the spray drying, which is an easy to scale up technique. The findings herein stimulate further in vivo evaluations and clinical tests as a cancer and Alzheimer chemoprevention agent.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Curcumina/química , Curcumina/farmacocinética , Estabilidade de Medicamentos , Animais , Anti-Inflamatórios/farmacologia , Disponibilidade Biológica , Química Farmacêutica/métodos , Curcumina/farmacologia , Gorduras/química , Gorduras/farmacocinética , Gorduras/farmacologia , Masculino , Óleos/química , Óleos/farmacocinética , Óleos/farmacologia , Ratos , Ratos Wistar , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Dióxido de Silício/farmacologia , Solubilidade , Tecnologia Farmacêutica/métodos , Difração de Raios X/métodos
14.
Clin Genet ; 88(5): 456-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25307543

RESUMO

Pathogenic mutations in genes COL4A3/COL4A4 are responsible for autosomal Alport syndrome (AS) and thin basement membrane nephropathy (TBMN). We used Sanger sequencing to analyze all exons and splice site regions of COL4A3/COL4A4, in 40 unrelated Portuguese probands with clinical suspicion of AS/TBMN. To assess genotype-phenotype correlations, we compared clinically relevant phenotypes/outcomes between homozygous/compound heterozygous and apparently heterozygous patients. Seventeen novel and four reportedly pathogenic COL4A3/COL4A4 mutations were identified in 62.5% (25/40) of the probands. Regardless of the mutated gene, all patients with ARAS manifested chronic renal failure (CRF) and hearing loss, whereas a minority of the apparently heterozygous patients had CRF or extrarenal symptoms. CRF was diagnosed at a significantly younger age in patients with ARAS. In our families, the occurrence of COL4A3/COL4A4 mutations was higher, while the prevalence of XLAS was lower than expected. Overall, a pathogenic COL4A3/COL4A4/COL4A5 mutation was identified in >50% of patients with fewer than three of the standard diagnostic criteria of AS. With such a population background, simultaneous next-generation sequencing of all three genes may be recommended as the most expedite approach to diagnose collagen IV-related glomerular basement membrane nephropathies.


Assuntos
Autoantígenos/genética , Colágeno Tipo IV/genética , Hematúria/genética , Mutação , Nefrite Hereditária/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise Mutacional de DNA , Exoma , Feminino , Estudos de Associação Genética , Hematúria/diagnóstico , Hematúria/metabolismo , Humanos , Falência Renal Crônica/genética , Falência Renal Crônica/metabolismo , Masculino , Pessoa de Meia-Idade , Nefrite Hereditária/diagnóstico , Nefrite Hereditária/metabolismo , Portugal , Adulto Jovem
15.
J Dairy Sci ; 98(6): 3918-25, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25892694

RESUMO

Our objectives were to evaluate the acute effects of a controlled internal drug release (CIDR) insert containing 1.38 g of progesterone (P4) on the release of LH, follicular growth, and circulating concentrations of P4 in cows treated with GnRH at the time of CIDR insertion. Nonpregnant, lactating dairy cows (n=27) were blocked by parity, predicted 305-d mature-equivalent milk production, and body condition score and randomly assigned to 1 of 3 treatments: (1) CIDR insertion concurrent with an injection of 200 µg of GnRH (n=10; 2GP4); (2) CIDR insertion concurrent with an injection of 100 µg of GnRH (n=10; 1GP4); and (3) injection of 100 µg of GnRH (n=7; CON). Prior to onset of treatments, cows were submitted to a presynchronization protocol that consisted of a CIDR insert containing 1.38 g of P4 from d -7 to -2, 25mg of PGF2α on d -2 and -1, and 100 µg of GnRH on d 0. Experimental treatments were applied on d 6, the early luteal phase of the estrous cycle. Concentrations of P4 in plasma were determined on d -2 and 0 and at 0, 15, 30, 60, 120, 240, 345, 600, and 1,200 min relative to treatment on d 6. Concentrations of LH were determined in plasma samples obtained at 0, 15, 30, 60, 120, 240, and 345 min relative to treatment on d 6. Ultrasonography examinations of ovarian structures were performed on d -2, 0, 2, and at 0, 600, and 1,200 min relative to treatment on d 6. Mean concentrations of P4 in the CON group (1.91±0.28 ng/mL) were lower than in 2GP4 (3.40±0.26 ng/mL) and 1GP4 (3.31±0.24 ng/mL) groups, but concentrations in 2GP4 and 1GP4 were similar. Mean concentration of LH in response to the GnRH injection on d 6 was greatest in 2GP4 cows (3.08±0.21 ng/mL) and did not differ between 1GP4 (2.23±0.21 ng/mL) and CON (2.14±0.25 ng/mL) cows. The diameter of the dominant follicle on d 6 was similar among treatments (2GP4=15.34±0.50; 1GP4=15.31±0.50; CON=14.77±0.62 mm). In conclusion, CIDR insertion concurrent with a 100- or 200-µg dose of GnRH neither altered GnRH-induced LH release nor had an acute effect on dominant follicle growth.


Assuntos
Bovinos/fisiologia , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Luteinizante/sangue , Progesterona/administração & dosagem , Administração Intravaginal , Animais , Preparações de Ação Retardada , Dinoprosta/administração & dosagem , Ciclo Estral/efeitos dos fármacos , Sincronização do Estro , Feminino , Lactação , Folículo Ovariano/efeitos dos fármacos , Ovário/diagnóstico por imagem , Paridade , Gravidez , Distribuição Aleatória
16.
J Dairy Sci ; 98(5): 3236-46, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25726103

RESUMO

The transition from late gestation to early lactation is characterized by substantial metabolic stress and altered immune function. The objective of this study was to assess the effects of supplementing a yeast product derived from Saccharomyces cerevisiae on immunity and uterine inflammation in transition cows. Forty multiparous Holstein cows were blocked by expected parturition date and randomly assigned within block to 1 of 4 treatments (n=10) from 21d before expected parturition to 42d postpartum. Rations were top-dressed with a product containing yeast culture plus enzymatically hydrolyzed yeast (YC-EHY; Celmanax, Vi-COR, Mason City, IA) at the rate of 0, 30, 60, or 90g/d throughout the experiment. Cows were injected subcutaneously with ovalbumin on d -21, -7, and 14 to assess their humoral response. Data were analyzed using mixed models with repeated measures over time. Concentrations of colostrum IgG were unaffected by treatments. A treatment × week interaction was observed for somatic cell linear score, reflecting a tendency for a quadratic dose effect on wk 1 (2.34, 2.85, 1.47, and 4.06±0.59 for 0, 30, 60, and 90g/d, respectively) and a quadratic dose effect on wk 5 (1.36, -0.15, -1.07, and 0.35±0.64 for 0, 30, 60, and 90g/d, respectively). Platelet count was increased by YC-EHY. Increasing YC-EHY dose linearly increased plasma anti-ovalbumin IgG levels following 3 ovalbumin challenges, suggesting that treatments enhanced humoral immunity. Increasing YC-EHY dose also quadratically increased fecal IgA concentrations in early lactation, suggesting that 30 and 60g/d doses enhanced mucosal immunity. Uterine neutrophil populations were much greater in samples collected on d 7 compared with those on d 42 (32.1 vs. 7.6±3.5% of cells), reflecting neutrophil infiltration immediately after calving, but no treatment effect was detected. Significant day effects were detected for mRNA of IL-6, IL-8, neutrophil myeloperoxidase (MPO), and neutrophil elastase (ELANE) in the uterine samples, reflecting greater abundance of these transcripts collected on d 7 compared with d 42. A quadratic dose effect was detected for IL-6, indicating that 30 and 60g/d doses decreased uterine IL-6 mRNA. The mRNA abundance of MPO and ELANE was increased linearly by YC-EHY. Supplementation with YC-EHY enhanced measures of humoral and mucosal immunity and modulated uterine inflammatory signals and mammary gland health in transition dairy cows.


Assuntos
Bovinos/imunologia , Imunidade Humoral , Imunidade nas Mucosas , Inflamação/veterinária , Fermento Seco/administração & dosagem , Animais , Colostro/química , Feminino , Haptoglobinas/metabolismo , Imunoglobulina A/metabolismo , Imunoglobulina G/sangue , Inflamação/terapia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Lactação , Leite/química , Neutrófilos/metabolismo , Ovalbumina/metabolismo , Paridade , Peroxidase/metabolismo , Período Pós-Parto/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/metabolismo , Doenças Uterinas/terapia , Doenças Uterinas/veterinária , Útero
17.
J Dairy Sci ; 98(1): 532-40, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25465565

RESUMO

Yeast supplementation has been shown to increase feed intake and production in some studies with early lactation dairy cows, but the mechanisms underlying such an effect remain unknown. The objective of this study was to assess the effects of supplementing a yeast product derived from Saccharomyces cerevisiae on production, feeding behavior, and metabolism in cows during the transition to lactation. Forty multiparous Holstein cows were blocked by expected calving date and randomly assigned within block to 1 of 4 treatments (n=10) from 21 d before expected calving to 42 d postpartum. Rations were top-dressed with a yeast culture plus enzymatically hydrolyzed yeast (YC-EHY; Celmanax, Vi-COR Inc., Mason City, IA) at the rate of 0, 30, 60, or 90g/d throughout the experiment. Dry matter and water intake, feeding behavior, and milk production were monitored. Plasma samples collected on -21, -7, 1, 4, 7, 14, 21, and 35 d relative to calving were analyzed for glucose, ß-hydroxybutyrate, and nonesterified fatty acids. Data were analyzed using mixed models with repeated measures over time. Pre- or postpartum dry matter intake and water intake did not differ among treatments. Quadratic dose effects were observed for prepartum feeding behavior, reflecting decreased meal size, meal length, and intermeal interval, and increased meal frequency for cows received 30 and 60g/d of YC-EHY. Postpartum feeding behavior was unaffected by treatments. Milk yields were not affected (45.3, 42.6, 47.8, and 46.7kg/d for 0, 30, 60, and 90g/d, respectively) by treatments. Tendencies for increased percentages of milk fat, protein, and lactose were detected for cows receiving YC-EHY. Supplementing YC-EHY increased plasma ß-hydroxybutyrate and tended to decrease (quadratic dose effect) glucose but did not affect nonesterified fatty acids. Yeast product supplementation during the transition period did not affect milk production and dry matter intake but modulated feeding behavior and metabolism.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Bovinos/fisiologia , Dieta/veterinária , Suplementos Nutricionais , Comportamento Alimentar/fisiologia , Metabolismo dos Lipídeos/fisiologia , Saccharomyces cerevisiae/química , Ração Animal/análise , Animais , Biomarcadores/metabolismo , Feminino , Glucose/metabolismo , Lactação , Leite/metabolismo , Distribuição Aleatória
18.
J Dairy Sci ; 97(2): 805-18, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24290816

RESUMO

Objectives of the current experiment were to evaluate plasma concentrations of metabolites and haptoglobin peripartum, uterine health and involution, and follicle growth and resumption of cyclicity of Holstein (HO) and Montbéliarde-sired crossbred cows. Cows (52 HO and 52 crossbred) were enrolled in the study 45 d before expected calving date. Cows had body weight and body condition score recorded on d -45, -14, 0, 1, 28, and 56 relative to calving. Dry matter intake was calculated for a subgroup of cows (25 HO and 38 crossbred) from 6 wk before to 6 wk after calving. Blood was sampled weekly from d -14 to 56 relative to calving for determination of glucose, nonesterified fatty acid, and ß-hydroxybutyrate concentrations; from d -7 to 21 relative to calving for determination of haptoglobin concentration; and from d 14 to 56 postpartum for determination of progesterone concentration. Cows were examined at calving and on d 4, 7, 10, and 14 postpartum for diagnosis of postparturient diseases, on d 24 postpartum for diagnosis of purulent vaginal discharge, and on d 42 postpartum for diagnosis of subclinical endometritis. Uteri and ovaries were examined by ultrasonography every 3 d from d 14 to 41 postpartum. Milk yield and composition were measured monthly and yield of milk, fat, protein, and energy-corrected milk were recorded for the first 90 d postpartum. Body weight was not different between Holstein and crossbred cows, but HO cows had reduced body condition score compared with crossbred cows. Even though DMI from 6 wk before to 6 wk after calving tended to be greater for HO cows (16.8 ± 0.7 vs. 15.3 ± 0.5 kg/d), HO cows tended to have more pronounced decline in dry matter intake, expressed in percentage of body weight from d -15 to 0 relative to calving. Energy-corrected milk and nonesterified fatty acid and ß-hydroxybutyrate concentrations were not different between breeds. No differences were observed in incidence of retained fetal membranes, metritis, and subclinical endometritis, but HO cows tended to be more likely to have pyrexia from d 0 to 15 postpartum (50.0 vs. 31.4%) and to have greater incidence of purulent vaginal discharge (44.2 vs. 26.5%) than crossbred cows. Holstein cows were more likely to have at least 1 uterine disorder postpartum than crossbred cows (63.5 vs. 36.7%). No differences between breeds were observed in uterine involution. Holstein cows had larger subordinate follicles (10.1 ± 0.4 vs. 8.9 ± 0.5) and a greater number of class III follicles (1.6 ± 0.1 vs. 1.2 ± 0.1) than crossbred cows. Furthermore, the first corpus luteum postpartum of HO cows was diagnosed at a slower rate compared with crossbred cows. Crossbred cows had improved uterine health compared with HO cows and this may have been a consequence of heterosis and (or) breed complementarity and less pronounced decrease in DMI during the last days of gestation.


Assuntos
Doenças dos Bovinos/fisiopatologia , Metabolismo Energético , Folículo Ovariano/fisiologia , Útero/fisiologia , Animais , Bovinos , Doenças dos Bovinos/etiologia , Doenças dos Bovinos/genética , Feminino , Haptoglobinas/metabolismo , Hibridização Genética , Endogamia , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/fisiopatologia , Período Periparto , Período Pós-Parto , Útero/fisiopatologia
19.
J Dairy Sci ; 97(1): 185-94, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24183690

RESUMO

The objectives of this study were to evaluate effects of 2 resynchronization protocols beginning at different intervals after artificial insemination (AI) on the pattern of return to estrus, ovarian responses, and pregnancy per AI (P/AI) to reinsemination. Lactating cows from 2 dairies, located in Texas (n=2,233) and Minnesota (n=3,077), were assigned to 1 of 4 timed AI (TAI) protocols 17 ± 3 d after AI. All cows were examined for pregnancy 31 ± 3 d after previous AI. Cows assigned to early Ovsynch56 (E-OV56) or OV56 received the Ovsynch56 protocol starting 24 or 31 d after AI, respectively. Cows assigned to early GnRH-GnRH-PGF(2α)-GnRH (E-GGPG) or GGPG received a presynchronizing GnRH injection 17 or 24 d after AI, respectively, 7 d before the start of the Ovsynch56 protocol. Cows observed in estrus after enrollment were inseminated on the same day. Ovaries were examined and blood was sampled for progesterone concentration on the day of first GnRH and PGF(2α) injection of the Ovsynch56 protocol. Pregnancy was diagnosed at 31 and 66 d after resynchronized AI. On the day of the first GnRH injection of the TAI, a higher percentage of cows on E-GGPG and GGPG protocols had a corpus luteum (E-GGPG=83.8, GGPG=91.2, E-OV56=80.4, and OV56=75.5%) and progesterone concentration >1 ng/mL (E-GGPG=62.5, GGPG=76.0, E-OV56=53.6, and OV56=60.8%) than cows assigned to other protocols. However, the percentage of cows ovulating to the first GnRH injection of TAI was not affected by treatment. Fewer E-GGPG and more OV56 cows were reinseminated in estrus (E-GGPG=23.7, GGPG=49.0, E-OV56=41.6, and OV56=57.6%). Treatment did not affect P/AI at 31 or 66 d for cows reinseminated in estrus. However, cows reinseminated in estrus had greater P/AI at 31 (40.0 vs. 27.5%) and 66 d (36.0 vs. 23.9%) than cows completing the TAI protocols. Among cows completing the TAI protocols, initiation of GGPG at 24 d after AI increased, whereas initiation of Ovsynch56 at 24 d after AI decreased P/AI at 31 d after reinsemination (E-GGPG=30.6, GGPG=28.3.0, E-OV56=22.3, and OV56=28.7%). Pregnancy per AI did not differ across treatment at 66 d after TAI (E-GGPG=26.6, GGPG=24.4, E-OV56=20.0, and OV56=24.1%). Overall, type of resynchronization protocol and protocol initiation time did not affect P/AI 66 d after reinsemination (E-GGPG=29.7, GGPG=30.5, E-OV56=26.1, and OV56=30.4%). In conclusion, GGPG resynchronization protocols and initiation of resynchronization protocol 24 d after AI reduced the number of cows reinseminated in estrus but neither the timing of initiation of resynchronization nor presynchronization with GnRH affected overall P/AI.


Assuntos
Sincronização do Estro/métodos , Fertilidade/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Injeções/métodos , Lactação/efeitos dos fármacos , Animais , Bovinos , Corpo Lúteo/efeitos dos fármacos , Dieta/veterinária , Estro/efeitos dos fármacos , Sincronização do Estro/efeitos dos fármacos , Feminino , Fertilidade/fisiologia , Inseminação Artificial/veterinária , Lactação/fisiologia , Modelos Logísticos , Minnesota , Ovário/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Ovulação/fisiologia , Gravidez , Progesterona/sangue , Texas
20.
Oper Dent ; 49(2): 157-165, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38349817

RESUMO

OBJECTIVES: To evaluate the volume and depth of enamel loss promoted by 37.5% and 7.5% hydrogen peroxide (HP) gels, and quantify the loss of calcium (Ca) and phosphate (P) ions by using ion chromatography (IC) analysis after bleaching. METHODS: Sixty bovine enamel specimens were randomly divided into three groups: Control - no bleaching gel; HP37.5%, application of HP 37.5% for 45 minutes for 14 days; and HP7.5%, application of HP 7.5% for 3 applications of 8 minutes. The surface analysis (n=5) was performed using a scanning electron microscope (SEM) and dispersive energy system (EDS) to calcium and phosphorus dosage. The micro-CT was used for the enamel loss analysis (n=5). IC was used to analyze extracted Ca and P (n=10). Data were analyzed by one-way ANOVA and two-way repeated measures ANOVA, followed by Tukey and Dunnett's tests (α=0.05). RESULTS: Significantly higher volume and depth of enamel loss were found for bleached groups compared with the control group. HP7.5% had significantly higher enamel change than HP37.5%. SEM showed higher enamel porosity for HP37.5% and HP7.5% compared to control. The IC demonstrated a significant increase of Ca incorporated into the gel, however, only HP7.5% had a higher P presence than the control group. The HP7.5% showed higher Ca and P ion exchange than HP37.5% (p<0.001). CONCLUSION: HP37.5% and HP7.5%, caused enamel mineral changes compared with the control group. The IC method was demonstrated to be an effective methodology for detecting enamel mineral loss by the bleaching gel.


Assuntos
Clareadores Dentários , Clareamento Dental , Animais , Bovinos , Cálcio , Clareamento Dental/métodos , Esmalte Dentário , Microtomografia por Raio-X , Peróxido de Hidrogênio/química , Minerais , Fosfatos , Géis
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