Somatostatin receptors in normal and acromegalic somatotroph cells: the U-turn of the clinician to immunohistochemistry report - a review.

This is a narrative review of literature introducing somatostatin receptors (SSTRs) as part of understanding the somatotroph cells since they are positive in normal cells but also in tumoral cells as seen in somatotropinoma, a growth hormone (GH)-producing neoplasia, which causes acromegaly. They are five subtypes of SSTRs (1 to 5), which are immunohistochemically positive in different proportions in somatotropinomas. SSTR types 2 and 5 are most frequent in GH-secreting adenomas and they are both targeted by medical therapy with somatostatin analogues (SSTAs) like first generation Octreotide and Lanreotide (mainly targeting SSTR2) and second generation Pasireotide (with highest affinity for SSTR5), thus heterogeneous SSTRs configuration into the tumor explains different pattern of response to treatment and it might predict it once the SSTRs immunostaining is performed. Monoclonal antibodies are used for immunohistochemical detection of SSTRs; currently, a lack of standardization is presented, and scoring systems, such as Volante, H-score or human epidermal growth factor receptor 2 (HER2)-score, are applied. Immunoreactive markers like SSTRs are the U-turn in clinical practice regarding somatotropinomas since the configuration of subtypes 2 and 5 explains the responsiveness to medical therapy like SSTA. Further achievement of disease control is imperiously necessary because acromegaly has an increased rate of morbidity and mortality.

Expression of Pentraxin 3 and Thrombospondin 1 in Gingival Crevicular Fluid during Wound Healing after Gingivectomy in Postorthodontic Patients.

Background. Wound healing is a tissue repair process after an injury, and two of its main components are inflammation and angiogenesis, in which course a cascade of mediators is involved. The aim of this research was to evaluate the involvement of Pentraxin 3 and Thrombospondin 1 in wound healing after periodontal surgery (gingivectomy) for gingival overgrowth during orthodontic treatment with or without magnification devices, by assessing their levels in GCF. Methods. From 19 patients with gingival overgrowth as a result of fixed orthodontic treatment, the overgrown gingiva was removed by gingivectomy, from one half of the mandibular arch without magnification and from the other under magnification. Pentraxin 3 and Thrombospondin 1 were determined from gingival crevicular fluid by ELISA tests. Results. Statistically significant differences (p < 0.05) and correlations between levels of the two biomarkers were analyzed. Statistically significant differences were established between levels of the two biomarkers at different time points, with significant positive correlation at the point of 24 hours. Conclusions. Within the limitations of this study, the results seem to sustain the involvement of Pentraxin 3 and Thrombospondin 1 in the processes of inflammation and angiogenesis in wound healing of patients with postorthodontic gingivectomy. The dynamics of Pentraxin 3 and Thrombospondin 1 levels could suggest a reduced inflammation and a faster angiogenesis using microsurgery.

Salivary and serum biomarkers for the study of side effects of aripiprazole coprescribed with mirtazapine in rats.

The aim of this study was to investigate whether the co-administration of aripiprazole and mirtazapine could determine weight gain and lipid metabolism disorders in Wistar rats, compared to the same side effects produced by mirtazapine alone, and the risk of hepatotoxicity due to the combination of the two substances. Tumor necrosis factor alpha (TNF-α), liver fatty acid binding protein (L-FABP/FABP1) and repulsive guidance molecule C/hemojuvelin (RGM-C/HJV) levels were determined in serum and in saliva. Also, serum levels for total cholesterol (TC), low and high-density lipoprotein (LDL, HDL), triglycerides (TG), aspartate aminotransferase (ASAT) and alanine amino transferase (ALAT) were assessed. We found positive and statistically significant correlations between serum and salivary levels of TNF-α, L-FABP/FABP1 and RGM-C/HJV. Mirtazapine determined significantly differences of TNF-α and L-FABP serum levels; final body weight; TC and LDL levels, leading to higher concentrations than its association with aripiprazole. Although not statistically significant, mirtazapine group experienced higher values for salivary levels of TNF-α, TG and ASAT, and lower values for HDL, compared to aripiprazole + mirtazapine group. The results suggest that aripiprazole might improve some of the disturbances caused by mirtazapine, and that the two drugs combination cause no additional alterations in liver function. Also, the findings indicate that TNF-α, L-FABP/FABP1 and RGM-C/HJV levels can be helpful as biomarkers for metabolic disturbances and impaired function of hepatocytes, and that their salivary determination can replace serum determination.

Heterogeneity of collagen secreting cells in gingival fibrosis--an immunohistochemical assessment and a review of the literature.

AIM: In this work, we compared the histological features of the gingival lesions clinically diagnosed as fibrotic overgrowths due to various etiologic factors as well as an immunohistochemical assessment of fibroblasts phenotypic heterogeneity using the specific labeling for vimentin, α-smooth muscle actin (α-SMA) and fibroblast specific protein-1 (FSP1). MATERIALS AND METHODS: Tissue samples were obtained from 12 patients clinically diagnosed with fibrotic gingival overgrowth, divided in four groups. Fragments of gingiva were processed for paraffin embedding. Serial sections were used for routine staining Hematoxylin-Eosin, trichromic Masson and Goldner-Szekely, and for immunohistochemical reactions to label vimentin, α-SMA and FSP1 using for signal amplification several techniques (EnVision, LSAB, ABC). RESULTS: Storage of collagen fibers, increase of fibroblast number and frequent presence of inflammatory infiltrate are histological issues of all fibrotic gingival overgrowth. The incidence of granulation tissue varies but the frequency of its presence point the attention to the involvement in collagen metabolism imbalance. Immunostaining for vimentin showed a difference between its expression in samples from different groups. Except the cases of fibrosis induced by orthodontic devices, cells positive for α-SMA were rare. FSP1-positive fibroblasts were the most frequent in all cases from all the groups selected for this study. CONCLUSIONS: The phenotype of fibroblasts is different in gingival fibrosis in relation to the risk factor, at present the most common being vimentin-positive and FSP1-positive fibroblasts. Myofibroblasts are rare in gingival fibrosis, the most numerous being in local lesions caused by wearing orthodontic devices and in syndromic fibromatosis. Further studies are required to elucidate the manner in which the active fibroblasts are recruited in relation to the etiologic factor of gingival overgrowth.

Involvement of TSP1 and MMP9/NGAL in angiogenesis during orthodontic periodontal remodeling.

In the present study the aim was to measure the levels of Thrombospondin-1 (TSP1) and Lipocalin-2/matrix metalloproteinase 9 (MMP9/NGAL) complex in gingival crevicular fluid (GCF) at different time points of orthodontic treatment, to determine the relationship between these values and those of total-matrix metalloproteinase 9 (MMP9) and theirs implication in angiogenesis balance, in the situation of a good control of the bacterial plaque, emphasizing the role of TSP1 and MMP9/NGAL complex. GCF samples were collected from 16 young orthodontic patients requiring upper canine distalization (test tooth) with first premolar extraction. The contralateral canine (control tooth) was free from orthodontic force. For the orthodontic appliance, brackets Roth 0.018 inch with 0.012 inch NiTi archwire and a laceback were used. TSP1, MMP9/NGAL, and MMP9 increased from 1 hour before activation of orthodontic appliance to a maximum at 8 hours for MMP9 and 72 hours for MMP9/NGAL and TSP1. The results show a change in time of TSP1, MMP9/NGAL, and MMP9 levels in GCF of patients with this method of orthodontic treatment. The powerful correlation of MMP9/NGAL with TSP1 suggests their stronger involvement in angiogenesis processes in PDL during orthodontic periodontal remodeling, in the situation of a healthy periodontium and a good control of the bacterial plaque.

Study on the histopathological modifications of the dental pulp in occlusal trauma.

The diagnosis of occlusion-generated disorders of the dento-maxillary apparatus represents a sensitive stage within the establishment of the therapeutic means for the functional rehabilitation of dental arches. The laborious effort carried out in order to specify the diagnosis resides in the fact that any trauma arising at the level of any component of the stomatognate system may lead to an occlusal dysfunction. The uncured carious processes, besides the pulp and periapical complications, may lead to an occlusal dysfunction through horizontal migrations of teeth resulting in the derangement of the occlusal curvatures as well as through vertical migrations of the teeth opposing a tooth diagnosed with occlusal caries or which largely reduced the coronary height. The dental iatrogenia, besides the eructation anomalies and neuromuscular dysfunction within the oromaxillofacial area also determines the appearance of occlusal dysfunction. The radiological examination through correlation with the clinical manifestations may provide significant data related to the magnitude of the prejudice caused to dento-paradontal units experiencing occlusal trauma. The histopathological study through correlation with the clinical manifestations provides significant data on the tolerance of dento-paradontal units within the occlusal dysfunction. Also, subsequent to the analysis of the possible actions of aggression generated by the occlusal trauma correlations could be determined between the type of the histological lesion of the pulp-dentine complex and the etiopathogenic factors, as well as correlations depending on the damage degree through occlusal trauma of the dental parts involved.

Matrix metalloproteinase 9 levels in gingival crevicular fluid in patients after periodontal microsurgery for orthodontic induced gingival hypertrophy.

INTRODUCTION: In this study, we aim to compare the levels of matrix metalloproteinase 9 (MMP9) in the gingival crevicular fluid (GCF), as indicators for healing, in two groups of patients - operated with a classic periodontal surgical technique and the same technique but using a dental microscope. MATERIALS: We included 14 patients with ages between 12 and 26 years, average 14±6.2 years. Eight patients were women and six men. All patients presented gingival hypertrophy because of the orthodontic treatment on the mandibular arch. We performed gingivectomy on one-half of the mandibular arch by classic periodontal surgery and on the other half of the mandibular arch by a microscope-assisted gingivectomy. METHODS: In the hypertrophied gingiva, the expression of MMP9 was identified using immunohistochemical-staining techniques. For immunological determination of MMP9 in GCF we performed Elisa tests. RESULTS: We found different levels in different moments of the healing process for the two hemiarcades. CONCLUSIONS: We consider that faster healing in case of microscope-assisted gingivectomy may be related to the expression of MMP-9 in the GCF.