73 resultados para Salivary gland


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Pregnancy diagnostics in equine reproduction are routinely performed using transrectal ultrasonography, although it is also possible to visualize the fetus by transabdominal ultrasound examinations from the 90th day of gestation onward. We hypothesized that ultrasound examinations may stress the mare and that the gestational stage status and lactation may influence the mare's stress reaction. To investigate the stress reaction, 25 thoroughbred mares of different age, pregnancy and lactational status underwent a transrectal examination. In pregnant mares, an additional transabdominal examination was performed. Salivary cortisol concentration, mean heart rate, and heart rate variability of mares were assessed to evaluate the reactions of hypothalamic–pituitary–adrenal (HPA) axis and of the autonomic nervous system. Significant differences were observed between lactating and nonlactating mares; with a lower responsiveness to stress in lactating mares. The transrectal ultrasound examination in nonlactating mares induced a significant increase in salivary cortisol (P < 0.05), and in the heart rate variability parameter, ratio of low to high frequencies (P < 0.05). This reflects an activation of the HPA axis and a shift to more sympathetic dominance. In contrast, a transabdominally performed pregnancy check did not induce an activation of the HPA axis over basal level but increased the mean heart rate and low to high frequency ratio. The results of this study indicate that checks of advanced pregnancies can be easily performed by transabdominal ultrasonography. With regard to animal welfare, this technique should be preferred during midgestation in nonlactating mares.

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Aim: To evaluate the effects of salivary contamination and decontamination on bond strength of two one-step adhesives to primary and permanent dentin. Methods: Dentin specimens were prepared from extracted primary and permanent molars (210 of each) and were distributed to seven groups (n=15/group/molar type) for each adhesive (Xeno V+ and Scotchbond Universal): no saliva contamination (control); saliva contamination before or after light-curing of the adhesives followed either by air-drying, by rinsing with water and air-drying, or by rinsing with water, air-drying and reapplication of the adhesives. Resin composite was applied and the specimens were stored for 24h (37°C, 100% humidity). Then, shear bond strength (SBS) was measured and data analyzed with nonparametric ANOVA and Wilcoxon rank sum tests. Results: Saliva contamination reduced SBS of Xeno V+, the reduction being more pronounced when contamination occurred before light-curing than after. In both situations, decontamination involving reapplication of the adhesive restored SBS. Saliva contamination had no significant effect on Scotchbond Universal. There were no differences in SBS between primary and permanent teeth. Conclusion: Saliva contamination reduced SBS of Xeno V+, but not of Scotchbond Universal. SBS was restored when contaminated dentin was rinsed with water and air-dried followed by reapplication of the adhesive.

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Purpose: To evaluate the effects of human saliva contamination and two decontamination procedures at different stages of the bonding procedure on the bond strength of two one-step self-etching adhesives to primary and permanent dentin. Materials and Methods: Extracted human primary and permanent molars (210 of each) were ground to mid-coronal dentin. The dentin specimens were randomly divided into 7 groups (n = 15/group/molar type) for each adhesive (Xeno V+ and Scotchbond Universal): no saliva contamination (control); saliva contamination before or after light curing of the adhesives followed by air drying, rinsing with water spray/air drying, or by rinsing with water spray/air drying/reapplication of the adhesives. Resin composite (Filtek Z250) was applied on the treated dentin surfaces. The specimens were stored at 37°C and 100% humidity for 24 h. After storage, shear bond strength (SBS) was measured and data analyzed with nonparametric ANOVA followed by exact Wilcoxon rank sum tests. Results: Xeno V+ generated significantly higher SBS than Scotchbond Universal when no saliva contamination occurred. Saliva contamination reduced SBS of Xeno V+, with the reduction being more pronounced when contamination occurred before light curing than after. In both situations, decontamination involving reapplication of the adhesive restored SBS. Saliva contamination had no significant effect on Scotchbond Universal. There were no differences in SBS between primary and permanent teeth. Conclusion: Rinsing with water and air drying followed by reapplication of the adhesive restored bond strength to saliva-contaminated dentin.

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The importance of small ruminants to the dairy industry has increased in recent years, especially in developing countries, where it has a high economic and social impact. Interestingly and despite the fact that the mammary gland is the specialised milk production organ, very few authors studied the modifications occurring in the mammary gland through the lactation period in production animals, particularly in the small ruminants, sheep (Ovis aries) and goat (Capra hircus). Nevertheless, understanding the different mammary gland patterns throughout lactation is essential to improve dairy production. In addition, associating these patterns with different milking frequencies, lactation number or different diets is also of high importance, directly affecting the dairy industry. The mammary gland is commonly composed of parenchyma and stroma, which includes the ductal system, with individual proportions of each changing during the different periods and yields in a lactation cycle. Indeed, during late gestation, as well as during early to mid-lactation, mammary gland expansion occurs, with an increase in the number of epithelial cells and lumen area, which leads to increment of the parenchyma tissue, as well as a reduction of stroma, corresponding macroscopically to the increase in mammary gland volume. Throughout late lactation, the mammary gland volume decreases owing to the regression of the secretory structure. In general, common mammary gland patterns have been shown for both goats and sheep throughout the several lactation stages, although the number of studies is limited. The main objective of this manuscript is to review the colostrogenesis and lactogenesis processes as well as to highlight the mammary gland morphological patterns underlying milk production during the lactation cycle for small ruminants, and to describe potential differences between goats and sheep, hence contributing to a better description of mammary gland development during lactation for these two poorly studied species.

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OBJECTIVE: To investigate effects of intramammary administration of prednisolone on the immune response of mammary glands in cows. ANIMALS: 5 lactating Red Holsteins. PROCEDURES: Cows received a different intramammary infusion in each mammary gland (10 mg of prednisolone, 100 μg of lipopolysaccharide [LPS], 100 μg of LPS and 10 mg of prednisolone, or saline [0.9% NaCl] solution). Milk samples were collected before (time 0) and 3, 6, 9, 12, 24, and 36 hours after treatment. Somatic cell count (SCC), lactate dehydrogenase (LDH) activity, and concentrations of serum albumin (SA) and tumor necrosis factor (TNF)-α in milk and mRNA expression of TNF-α, interleukin (IL)-8, and IL-1β in milk somatic cells were analyzed. RESULTS: Saline solution or prednisolone did not change SCC, LDH activity, and SA and TNF-α concentrations in milk and mRNA expression of TNF-α, IL-1β, and IL-8 in milk somatic cells. The SCC and TNF-α concentration in milk increased similarly in glands infused with LPS, independent of prednisolone administration. However, the increase of LDH activity and SA concentration in milk after LPS infusion was diminished by prednisolone administration. The mRNA expression of TNF-α, IL-8, and IL-1β in milk somatic cells increased after LPS infusion and was unaffected by prednisolone. CONCLUSIONS AND CLINICAL RELEVANCE: Intramammary administration of prednisolone did not induce an immune response and did not change mRNA expression of TNF-α, IL-8, and L-1β during the response to intramammary administration of LPS. However, prednisolone reduced disruption of the blood-milk barrier. This could influence the severity and cure rate of mastitis.

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BACKGROUND: Mental stress reliably induces increases in salivary alpha amylase (sAA), a suggested surrogate marker for sympathetic nervous system (SNS) reactivity. While stress-induced sAA increases correlate with norepinephrine (NE) secretion, a potential mediating role of noradrenergic mechanisms remains unclear. In this study, we investigated for the first time in humans whether a NE-stress-reactivity mimicking NE-infusion with and without alpha-adrenergic blockade by phentolamine would induce changes in sAA. METHODS: In a single-blind placebo-controlled within-subjects design, 21 healthy men (29-66 years) took part in three different experimental trials varying in terms of substance infusion with a 1-min first infusion followed by a 15-min second infusion: saline-infusion (trial-1), NE-infusion (5 μg/min) without alpha-adrenergic blockade (trial-2), and with phentolamine-induced non-selective blockade of alpha1- and alpha2-adrenergic receptors (trial-3). Saliva samples were collected immediately before, during, and several times after substance infusion in addition to blood pressure and heart rate readings. RESULTS: Experimental trials significantly differed in sAA reactivity to substance-infusion (p=.001) with higher sAA reactivity following NE-infusion with (trial-3; p=.001) and without alpha-adrenergic-blockade (trial-2; p=.004) as compared to placebo-infusion (trial-1); sAA infusion reactivity did not differ between trial-2 and trial-3 (p=.29). Effective phentolamine application was verified by blood pressure and heart rate infusion reactivity. Salivary cortisol was not affected by NE, either with or without alpha-adrenergic-blockade. CONCLUSIONS: We found that NE-infusion stimulates sAA secretion, regardless of co-administered non-selective alpha-adrenergic blockade by phentolamine, suggesting that the mechanism underlying stress-induced sAA increases may involve NE.

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PURPOSE Whole saliva comprises components of the salivary pellicle that spontaneously forms on surfaces of implants and teeth. However, there are no studies that functionally link the salivary pellicle with a possible change in gene expression. MATERIALS AND METHODS This study examined the genetic response of oral fibroblasts exposed to the salivary pellicle and whole saliva. Oral fibroblasts were seeded onto a salivary pellicle and the respective untreated surface. Oral fibroblasts were also exposed to freshly harvested sterile-filtered whole saliva. A genome-wide microarray of oral fibroblasts was performed, followed by gene ontology screening with DAVID functional annotation clustering, KEGG pathway analysis, and the STRING functional protein association network. RESULTS Exposure of oral fibroblasts to saliva caused 61 genes to be differentially expressed (P < .05). Gene ontology screening assigned the respective genes into 262 biologic processes, 3 cellular components, 13 molecular functions, and 7 pathways. Most remarkable was the enrichment in the inflammatory response. None of the genes regulated by whole saliva was significantly changed when cells were placed onto a salivary pellicle. CONCLUSION The salivary pellicle per se does not provoke a significant inflammatory response of oral fibroblasts in vitro, whereas sterile-filtered whole saliva does produce a strong inflammatory response.

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OBJECTIVES/HYPOTHESIS Assess the diagnostic and prognostic relevance of intraglandular lymph node (IGLN) metastases in primary parotid gland carcinomas (PGCs). STUDY DESIGN Retrospective study at a tertiary referral university hospital. METHODS We reviewed the records of 95 patients with primary PGCs, treated at least surgically, between 1997 and 2010. We assessed the clinicopathological associations of IGLN metastases, their prognostic significance, and predictive value in the diagnosis of occult neck lymph node metastases RESULTS Twenty-four (25.26%) patients had IGLN metastases. This feature was significantly more prevalent in patients with advanced pT status (P = .01), pN status (P < .01), and overall stage (P < .001); high-risk carcinomas (P = .01); as well as in patients with treatment failures (P < .01). IGLN involvement was significantly associated with decreased univariate disease-free survival (P < .001). Positive and negative predictive values and accuracy for IGLN involvement in the detection of occult neck lymph node metastases were 63.64%, 90.48%, and 84.91%, respectively. The diagnostic values were generally higher in patients with low-risk subtype of PGCs. CONCLUSIONS IGLN involvement provides prognostic information and is associated with advanced tumoral stage and higher risk of recurrence. This feature could be used as a potential readout to determine whether a neck dissection in clinically negative neck lymph nodes is needed or not. LEVEL OF EVIDENCE 4.

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OBJECTIVES The aetiology of hyposalivation in haematopoietic stem cell transplantation (HSCT) recipients is not fully understood. This study examined the effects of treatment-related aetiological factors, particularly medications, on stimulated salivary flow in HSCT recipients. SUBJECTS AND METHODS Adult HSCT recipients (N = 118, 66 males, 27 autologous and 91 allogeneic transplants) were examined. Stimulated whole salivary flow rates (SWSFR) were measured before HSCT and at 6 and 12 months post-HSCT. Linear regression models were used to analyse the associations of medications and transplant-related factors with salivary flow rates, which were compared to salivary flow rates of generally healthy controls (N = 247). RESULTS The SWSFR of recipients were lower pre-HSCT (mean ± standard deviation, 0.88 ± 0.56 ml/min; P < 0.001), 6 months post-HSCT (0.84 ± 0.61; P < 0.001) and 12 months post-HSCT (1.08 ± 0.67; P = 0.005) than the SWSFR of controls (1.31 ± 0.65). In addition, hyposalivation (<0.7 ml/min) was more frequent among HSCT recipients pre-HSCT (P < 0.001), 6 months post-HSCT (P < 0.001) and 12 months post-HSCT (P = 0.01) than among controls. The SWSFR was observed to improve over time being significantly higher 12 months post-HSCT compared to pre-HSCT (P < 0.001). The observed decrease of salivary flow could not be explained by the examined transplant-related factors and medications. CONCLUSIONS Decreased stimulated salivary flow rates could not be explained by the examined factors alone; these findings indicate that hyposalivation in HSCT recipients exhibits a multifactorial aetiology. CLINICAL RELEVANCE All HSCT recipients should be considered to be at high risk of hyposalivation and consequent oral diseases, and they should be treated accordingly.

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Magnetic Resonance Imaging of the Pituitary Gland of Horses With Pituitary Pars Intermedia Dysfunction