Publications by authors named "Paulo Henrique Luiz de Freitas"

Objectives: To evaluate the reliability and reproducibility of an artificial intelligence (AI) software in identifying cephalometric points on lateral cephalometric radiographs considering four settings of brightness and contrast.

Methods And Materials: Brightness and contrast of 30 lateral cephalometric radiographs were adjusted into four different settings. Then, the control examiner (ECont), the calibrated examiner (ECal), and the CEFBOT AI software (AIs) each marked 19 cephalometric points on all radiographs.

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Objectives: This study aimed to examine if feeding lactating mice a calcium-insufficient diet while simultaneously administering alendronate (ALN) could potentially induce osteocytic osteolysis.

Methods: Lactating mice were fed calcium (Ca)-insufficient diets with or without ALN administration, and then their femurs were examined for TRAP and ALP, and observed by Kossa staining and transmission electron microscopy (TEM). Mice that had been fed a Ca-insufficient diet were then fed a Ca-containing diet, and their tibial sections were examined by isotope microscopy.

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Background: The intermittent administration of parathyroid hormone (PTH) has been prescribed to osteoporotic patients due to its bone anabolic effects. In addition to its actions on bone cells, PTH appears to affect bone-specific blood vessels. These blood vessels are derived from bone marrow sinusoids, which express EphB4, a hallmark of veinous vascular endothelial cells.

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Objectives: Recently, the biological functions of endomucin-positive blood vessels and closely associated αSMA-positive cells in long bones have been highlighted. The surrounding tissues of the flat bones, such as nasal bones covered with mucosa and lamina propria, are different from those of the long bones, indicating the different distributions of endomucin-positive blood vessels and αSMA-reactive cells in nasal bones. This study demonstrates the immunolocalization of endomucin-reactive blood vessels and αSMA-positive cells in the nasal conchae of 3- and 7-week-old mice.

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Objective: To verify the biological effects of parathyroid hormone (PTH) on the blood vessels in the bone, this study aimed to investigate histological alterations in endomucin-positive blood vessels and perivascular cells in murine femora after intermittent PTH administration. For comparison with blood vessels in the bone, we examined the distribution of endomucin-positive blood vessels and surrounding αSMA-immunoreactive perivascular cells in the liver, kidney, and aorta with or without PTH administration.

Methods: Six-week-old male C57BL/6J mice received hPTH [1-34] or vehicle for two weeks.

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Objective: To assess the reliability of CEFBOT, an artificial intelligence (AI)-based cephalometry software, for cephalometric landmark annotation and linear and angular measurements according to Arnett's analysis.

Methods: Thirty lateral cephalometric radiographs acquired with a Carestream CS 9000 3D unit (Carestream Health Inc., Rochester/NY) were used in this study.

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In this study, we examined the immunolocalization of podoplanin/E11, CD44, actin filaments, and phosphorylated ezrin in the osteoblasts on the verge of differentiating into osteocytes in murine femora and tibiae. When observing under stimulated emission depletion microscopy, unlike podoplanin-negative osteoblasts, podoplanin-positive osteoblasts showed a rearranged assembly of actin filaments along the cell membranes which resembled that of embedded osteocytes. In the metaphysis, i.

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Article Synopsis
  • * Control mice showed many vessels positive for endomucin but few for αSMA, whereas PTH-treated mice had enlarged endomucin-positive vessels and increased αSMA-positive cells nearby, indicating a change in vascular structure and cell composition.
  • * PTH administration also elevated levels of PTH/PTHrP receptors and VEGF in both osteoblasts and endothelial cells, suggesting that PTH enhances the development and size of bone-specific blood vessels and promotes the presence of certain cells associated with bone formation.
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To demonstrate the ultrastructure of osteocytic osteolysis and clarify whether osteocytic osteolysis occurs independently of osteoclastic activities, we examined osteocytes and their lacunae in the femora and tibiae of 11-week-old male wild-type and mice after injection of human parathyroid hormone (PTH) [1-34] (80 µg/kg/dose). Serum calcium concentration rose temporarily 1 hr after PTH administration in wild-type and mice, when renal arteries and veins were ligated. After 6 hr, enlargement of osteocytic lacunae was evident in the cortical bones of wild-type and mice, but not so in their metaphyses.

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  • The study investigates how vascular endothelial cells interact with septoclasts at the chondro-osseous junction in the tibiae of mice.
  • Findings show that CD31-positive endothelial cells and septoclasts invade the hypertrophic zone of cartilage, with septoclasts indicated to incorporate extracellular matrices.
  • The study concludes that vascular endothelial cells near the chondro-osseous junction work with septoclasts for coordinated invasion into cartilage, while those further away engage with osteoblasts involved in bone formation.
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In this study, we attempted to localize the immunoreactivities of podoplanin/E11/gp38 and CD44, a counterpart possessing a high affinity to podoplanin/E11/gp38, as well as endomucin-immunoreactive blood vessels in the regions of odontoblast layers and the underlying sub-odontoblastic layers in murine tooth germs. Endomucin-reactive small blood vessels were scattered throughout the dental papillae of the tooth germs at postnatal day 1 but came to be localized close to the odontoblast/sub-odontoblastic layers until day 3. After postnatal day 5, small blood vessels were seen in odontoblast cell layers, while blood vessels with relatively larger diameters were seen forming in sub-odontoblastic layers.

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  • - This study investigated how ascorbic acid (vitamin C) influences collagen production in the periodontal ligaments of specific rats that cannot produce it naturally, focusing on different concentrations given to control, insufficient, and rescued groups.
  • - The results revealed that rats with low ascorbic acid levels had fewer collagen fibers and abnormal fiber structures, while those receiving adequate levels showed a normal abundance of collagen and proper cellular function in the periodontal ligaments.
  • - Immunohistochemistry indicated that ascorbic acid deficiency affected the activation of important proteins related to collagen formation (MMP2 and cathepsin H), but suggesting that the fibroblasts still have the ability to produce collagen when sufficient ascorbic acid is available.
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Intermittent administration of human parathyroid hormone (1-34) (hPTH(1-34)) promotes anabolic action in bone by stimulating bone remodeling, while eldecalcitol, an analog of active vitamin D3, suppresses osteoclastic bone resorption, and forms new bone by minimodeling. We have examined the biological effects of combined administration of eldecalcitol and hPTH(1-34) on 9-week-old Wistar rats that underwent an ovariectomy (OVX) or Sham operation. They were divided into a Sham group, OVX with vehicle (OVX group), OVX with 10 µg/kg/day of hPTH(1-34) (PTH group), OVX with 20 ng/kg/day of eldecalcitol (eldecalcitol group) or OVX with 10 μg/kg/day of hPTH(1-34), and 20 ng/kg/day of eldecalcitol (combined group) for 4 or 8 weeks.

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Early and immediate loading of dental implants has become a routine procedure in dental practices throughout the world, but the histological feature of peri-implant bone has not been fully understood. Therefore, we aimed to elucidate the histological response of peri-implant bone bearing the early occlusal loading using rat models. Four-week-old male Wistar rats were subjected to extraction of their maxillary left first molars and had titanium implants inserted immediately into the post-extraction sockets.

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The aim of this study is to demonstrate the application of focused ion beam-scanning electron microscopy, FIB-SEM for revealing the three-dimensional features of osteocytic cytoplasmic processes in metaphyseal (immature) and diaphyseal (mature) trabeculae. Tibiae of eight-week-old male mice were fixed with aldehyde solution, and treated with block staining prior to FIB-SEM observation. While two-dimensional backscattered SEM images showed osteocytes' cytoplasmic processes in a fragmented fashion, three-dimensional reconstructions of FIB-SEM images demonstrated that osteocytes in primary metaphyseal trabeculae extended their cytoplasmic processes randomly, thus maintaining contact with neighboring osteocytes and osteoblasts.

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This study compared the perception of facial pleasantness and the need for intervention, as assessed by orthodontists, oral and maxillofacial (OMF) surgeons, and laypersons, in people of different ethnicities showing varying degrees of simulated laterognathism. Facial photographs were modified to simulate deviations in the lower face of women of African, Asian and Caucasian descent, ascending in two-degree steps from zero to eight degrees of deviation. Three groups of 20 individuals each (OMF surgeons, orthodontists, and laypersons) assessed the images and rated facial pleasantness on a numerical scale ranging from 0 to 10.

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To assess the chronological participation of sclerostin and FGF23 in bone metabolism, this study tracked the immunolocalization of sclerostin and FGF23 in the metaphyses of murine long bones from embryonic day 18 (E18) through 1 day after birth, 1 week, 2 weeks, 4 weeks, 8 weeks, and 20 weeks of age. We have selected two regions in the metaphyseal trabeculae for assessing sclerostin and FGF23 localization: close to the chondro-osseous junction, i.e.

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Purpose: The current data suggest that the presence of lower third molars predisposes the patient to a greater risk of mandibular angle fracture. Thus, the present review sought to determine whether an association exists between the presence of a lower third molar and the occurrence of a mandibular angle fracture in adults and to assess the influence of third molar position according to the Pell and Gregory classification.

Materials And Methods: The present study was a systematic review and meta-analysis of analytical observational studies.

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Article Synopsis
  • Matrix vesicle-mediated mineralization is a complex process involving both structural and chemical changes that facilitate the formation and growth of crystals.
  • Key proteins like TNAP, ENPP1, and Pit1 help transport phosphate ions into matrix vesicles, which is crucial for the mineralization process.
  • The balance between the production of pyrophosphate (by ENPP1) and its breakdown (by TNAP) is important, as this regulates the nucleation of calcium phosphate crystals that eventually form mineralized structures.
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Since osteoblastic activities are believed to be coupled with osteoclasts, we have attempted to histologically verify which of the distinct cellular circumstances, the presence of osteoclasts themselves or bone resorption by osteoclasts, is essential for coupled osteoblastic activity, by examining c-fos or c-src mice. Osteopetrotic c-fos deficient (c-fos) mice have no osteoclasts, while c-src deficient (c-src) mice, another osteopetrotic model, develop dysfunctional osteoclasts due to a lack of ruffled borders. c-fos mice possessed no tartrate-resistant acid phosphatase (TRAPase)-reactive osteoclasts, and showed very weak tissue nonspecific alkaline phosphatase (TNALPase)-reactive mature osteoblasts.

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To elucidate which of elevated serum concentration of inorganic phosphate (Pi) or disrupted signaling linked to αklotho/fibroblast growth factor 23 (FGF23) is a predominant regulator for senescence-related degeneration seen in αKlotho-deficient mice, we have examined histological alteration of the periodontal tissues in the mandibular interalveolar septum of αKlotho-deficient mice fed with Pi-insufficient diet. We prepared six groups of mice: wild-type, kl/kl, and αKlotho mice with normal diet or low-Pi diet. As a consequence, kl/kl and αKlotho mice showed the same abnormalities in periodontal tissues: intensely stained areas with hematoxylin in the interalveolar septum, dispersed localization of alkaline phosphatase-positive osteoblasts and tartrate-resistant acid phosphatase-reactive osteoclasts, and accumulation of dentin matrix protein 1 in the osteocytic lacunae.

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Minodronate is highlighted for its marked and sustained effects on osteoporotic bones. To determine the duration of minodronate's effects, we have assessed the localization of the drug in mouse bones through isotope microscopy, after labeling it with a stable nitrogen isotope ([(15)N]-minodronate). In addition, minodronate-treated bones were assessed by histochemistry and transmission electron microscopy (TEM).

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Study Objectives: Although volumetric changes of the upper airway occur following surgical advancement of the maxilla, few studies investigated these changes using three-dimensional imaging techniques. Thus, the goal of this study was to verify whether the surgical advancement of the maxilla affects the volume of the upper airway and to determine any association of these volume changes with sex and age.

Methods: Preoperative and postoperative cone-beam computed tomography (CBCT) scans of 14 patients (8 male and 6 female) who underwent maxillary advancement to correct skeletal class III deformities were assessed to determine the postoperative volumetric changes in the upper airway.

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To investigate the relationship between the WHO disability grading system for leprosy with the limitations to perform daily functional activities and the decrease in social participation in participants with leprosy. Participants with a diagnosis of leprosy were recruited at the dermatology ambulatory clinic of the University Hospital of Sergipe. In order to investigate the association of WHO disability grading system for leprosy with activities of daily living measured with the Screening Activity Limitation and Safety Awareness (SALSA) scale and with the social participation (P-scale), we performed an analysis with the Kruskal-Wallis test and the Spearman coefficient.

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In order to determine whether osteoclastic bone resorption is restarted after withdrawn of bisphosphonates, we conducted histological examinations on murine osteoclasts, osteoblasts and osteocytes after discontinuation of a daily regimen of alendronate (ALN) with a dosage of 1 mg/kg/day for 10 days. After drug discontinuation, metaphyseal trabecular number and bone volume remained unaltered for the first 4 days. Osteoclast number did not increase, while the number of apoptotic osteoclasts was elevated.

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