Preoperative visualization of the lingual nerve by 3D double-echo steady-state MRI in surgical third molar extraction treatment.

OBJECTIVES: To assess the lingual nerve (LN) visualization using a 3D double-echo steady-state MRI sequence (3D-DESS). MATERIALS AND METHODS: Three readers prospectively evaluated the LN for its continuous visibility in 3D-DESS MRI in 19 patients with an indication for removal of mandibular impacted third molars, using a 5-point scale (4 = excellent to 0 = none). Six LN anatomical intermediate points (IP) were selected and checked for their detectability by a 4-point scale (4 = yes to1 = no). Inter- and intra-rater agreement was evaluated using intraclass correlation coefficient and percentage of agreement. RESULTS: The average nerve continuity score was 3.3 ± 0.46. In 35% of the cases, the entire course was continuously visible. In 10%, the proximal and 60%, the distal part of the nerve was not continuously visible. Inter- and intra-reader agreement was good (ICC = 0.76, ICC = 0.75). The average detectability score of all IP was 3.7 ± 0.41. From IP1 to IP5, the detectability was excellent; meanwhile, IP6 had lower visibility. The inter- and intra-reader percentage of agreement was 77% and 87%. CONCLUSIONS: The 3D-DESS sequence allowed accurate and continuous visualization of the LN with high reproducibility in more than one-third of the patients. This could improve the preoperative clarification of the LN position and thereby reduce complications during dentoalveolar surgical interventions. CLINICAL RELEVANCE: 3D-DESS MRI might be beneficial in clinical scenarios where the second molar is elongated or presents a difficult rotational position while simultaneously having a close positional relationship to the third molar. Thereby, osteotomy performed more lingually, indicating extended lingual flap detachment may increase the risk of LN damage.

Orai1 Channel Inhibition Preserves Left Ventricular Systolic Function and Normal Ca2+ Handling After Pressure Overload.

BACKGROUND: Orai1 is a critical ion channel subunit, best recognized as a mediator of store-operated Ca2+ entry (SOCE) in nonexcitable cells. SOCE has recently emerged as a key contributor of cardiac hypertrophy and heart failure but the relevance of Orai1 is still unclear. METHODS: To test the role of these Orai1 channels in the cardiac pathophysiology, a transgenic mouse was generated with cardiomyocyte-specific expression of an ion pore-disruptive Orai1R91W mutant (C-dnO1). Synthetic chemistry and channel screening strategies were used to develop 4-(2,5-dimethoxyphenyl)-N-[(pyridin-4-yl)methyl]aniline (hereafter referred to as JPIII), a small-molecule Orai1 channel inhibitor suitable for in vivo delivery. RESULTS: Adult mice subjected to transverse aortic constriction (TAC) developed cardiac hypertrophy and reduced ventricular function associated with increased Orai1 expression and Orai1-dependent SOCE (assessed by Mn2+ influx). C-dnO1 mice displayed normal cardiac electromechanical function and cellular excitation-contraction coupling despite reduced Orai1-dependent SOCE. Five weeks after TAC, C-dnO1 mice were protected from systolic dysfunction (assessed by preserved left ventricular fractional shortening and ejection fraction) even if increased cardiac mass and prohypertrophic markers induction were observed. This is correlated with a protection from TAC-induced cellular Ca2+ signaling alterations (increased SOCE, decreased [Ca2+]i transients amplitude and decay rate, lower SR Ca2+ load and depressed cellular contractility) and SERCA2a downregulation in ventricular cardiomyocytes from C-dnO1 mice, associated with blunted Pyk2 signaling. There was also less fibrosis in heart sections from C-dnO1 mice after TAC. Moreover, 3 weeks treatment with JPIII following 5 weeks of TAC confirmed the translational relevance of an Orai1 inhibition strategy during hypertrophic insult. CONCLUSIONS: The findings suggest a key role of cardiac Orai1 channels and the potential for Orai1 channel inhibitors as inotropic therapies for maintaining contractility reserve after hypertrophic stress.

Involvement of CFTR in the pathogenesis of pulmonary arterial hypertension.

INTRODUCTION: A reduction in pulmonary artery relaxation is a key event in the pathogenesis of pulmonary arterial hypertension (PAH). Cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction in airway epithelial cells plays a central role in cystic fibrosis; CFTR is also expressed in pulmonary arteries and has been shown to control endothelium-independent relaxation. AIM AND OBJECTIVES: We aimed to delineate the role of CFTR in PAH pathogenesis through observational and interventional experiments in human tissues and animal models. METHODS AND RESULTS: Reverse-transcriptase quantitative PCR, confocal imaging and electron microscopy showed that CFTR expression was reduced in pulmonary arteries from patients with idiopathic PAH (iPAH) and in rats with monocrotaline-induced pulmonary hypertension (PH). Moreover, using myography on human, pig and rat pulmonary arteries, we demonstrated that CFTR activation induces pulmonary artery relaxation. CFTR-mediated pulmonary artery relaxation was reduced in pulmonary arteries from iPAH patients and rats with monocrotaline- or chronic hypoxia-induced PH. Long-term in vivo CFTR inhibition in rats significantly increased right ventricular systolic pressure, which was related to exaggerated pulmonary vascular cell proliferation in situ and vessel neomuscularisation. Pathologic assessment of lungs from patients with severe cystic fibrosis (F508del-CFTR) revealed severe pulmonary artery remodelling with intimal fibrosis and medial hypertrophy. Lungs from homozygous F508delCftr rats exhibited pulmonary vessel neomuscularisation. The elevations in right ventricular systolic pressure and end diastolic pressure in monocrotaline-exposed rats with chronic CFTR inhibition were more prominent than those in vehicle-exposed rats. CONCLUSIONS: CFTR expression is strongly decreased in pulmonary artery smooth muscle and endothelial cells in human and animal models of PH. CFTR inhibition increases vascular cell proliferation and strongly reduces pulmonary artery relaxation.

Characterization of Kcnk3-Mutated Rat, a Novel Model of Pulmonary Hypertension.

RATIONALE: Pulmonary arterial hypertension is a severe lethal cardiopulmonary disease. Loss of function mutations in KCNK3 (potassium channel subfamily K member 3) gene, which encodes an outward rectifier K+ channel, have been identified in pulmonary arterial hypertension patients. OBJECTIVE: We have demonstrated that KCNK3 dysfunction is common to heritable and nonheritable pulmonary arterial hypertension and to experimental pulmonary hypertension (PH). Finally, KCNK3 is not functional in mouse pulmonary vasculature. METHODS AND RESULTS: Using CRISPR/Cas9 technology, we generated a 94 bp out of frame deletion in exon 1 of Kcnk3 gene and characterized these rats at the electrophysiological, echocardiographic, hemodynamic, morphological, cellular, and molecular levels to decipher the cellular mechanisms associated with loss of KCNK3. Using patch-clamp technique, we validated our transgenic strategy by demonstrating the absence of KCNK3 current in freshly isolated pulmonary arterial smooth muscle cells from Kcnk3-mutated rats. At 4 months of age, echocardiographic parameters revealed shortening of the pulmonary artery acceleration time associated with elevation of the right ventricular systolic pressure. Kcnk3-mutated rats developed more severe PH than wild-type rats after monocrotaline exposure or chronic hypoxia exposure. Kcnk3-mutation induced a lung distal neomuscularization and perivascular extracellular matrix activation. Lungs of Kcnk3-mutated rats were characterized by overactivation of ERK1/2 (extracellular signal-regulated kinase1-/2), AKT (protein kinase B), SRC, and overexpression of HIF1-α (hypoxia-inducible factor-1 α), survivin, and VWF (Von Willebrand factor). Linked with plasma membrane depolarization, reduced endothelial-NOS expression and desensitization of endothelial-derived hyperpolarizing factor, Kcnk3-mutated rats presented predisposition to vasoconstriction of pulmonary arteries and a severe loss of sildenafil-induced pulmonary arteries relaxation. Moreover, we showed strong alteration of right ventricular cardiomyocyte excitability. Finally, Kcnk3-mutated rats developed age-dependent PH associated with low serum-albumin concentration. CONCLUSIONS: We established the first Kcnk3-mutated rat model of PH. Our results confirm that KCNK3 loss of function is a key event in pulmonary arterial hypertension pathogenesis. This model presents new opportunities for understanding the initiating mechanisms of PH and testing biologically relevant therapeutic molecules in the context of PH.

Microtubule polymerization state and clathrin-dependent internalization regulate dynamics of cardiac potassium channel: Microtubule and clathrin control of KV1.5 channel.

Ion channel trafficking powerfully influences cardiac electrical activity as it regulates the number of available channels at the plasma membrane. Studies have largely focused on identifying the molecular determinants of the trafficking of the atria-specific KV1.5 channel, the molecular basis of the ultra-rapid delayed rectifier current IKur. Besides, regulated KV1.5 channel recycling upon changes in homeostatic state and mechanical constraints in native cardiomyocytes has been well documented. Here, using cutting-edge imaging in live myocytes, we investigated the dynamics of this channel in the plasma membrane. We demonstrate that the clathrin pathway is a major regulator of the functional expression of KV1.5 channels in atrial myocytes, with the microtubule network as the prominent organizer of KV1.5 transport within the membrane. Both clathrin blockade and microtubule disruption result in channel clusterization with reduced membrane mobility and internalization, whereas disassembly of the actin cytoskeleton does not. Mobile KV1.5 channels are associated with the microtubule plus-end tracking protein EB1 whereas static KV1.5 clusters are associated with stable acetylated microtubules. In human biopsies from patients in atrial fibrillation associated with atrial remodeling, drastic modifications in the trafficking balance occurs together with alteration in microtubule polymerization state resulting in modest reduced endocytosis and increased recycling. Consequently, hallmark of atrial KV1.5 dynamics within the membrane is clathrin- and microtubule- dependent. During atrial remodeling, predominance of anterograde trafficking activity over retrograde trafficking could result in accumulation ok KV1.5 channels in the plasma membrane.

Bmpr2 Mutant Rats Develop Pulmonary and Cardiac Characteristics of Pulmonary Arterial Hypertension.

BACKGROUND: Monoallelic mutations in the gene encoding bone morphogenetic protein receptor 2 ( Bmpr2) are the main genetic risk factor for heritable pulmonary arterial hypertension (PAH) with incomplete penetrance. Several Bmpr2 transgenic mice have been reported to develop mild spontaneous PAH. In this study, we examined whether rats with the Bmpr2 mutation were susceptible to developing more severe PAH. METHODS: The zinc finger nuclease method was used to establish rat lines with mutations in the Bmpr2 gene. These rats were then characterized at the hemodynamic, histological, electrophysiological, and molecular levels. RESULTS: Rats with a monoallelic deletion of 71 bp in exon 1 (Δ 71 rats) showed decreased BMPRII expression and phosphorylated SMAD1/5/9 levels. Δ 71 Rats develop age-dependent spontaneous PAH with a low penetrance (16%-27%), similar to that in humans. Δ 71 Rats were more susceptible to hypoxia-induced pulmonary hypertension than wild-type rats. Δ 71 Rats exhibited progressive pulmonary vascular remodeling associated with a proproliferative phenotype and showed lower pulmonary microvascular density than wild-type rats. Organ bath studies revealed severe alteration of pulmonary artery contraction and relaxation associated with potassium channel subfamily K member 3 (KCNK3) dysfunction. High levels of perivascular fibrillar collagen and pulmonary interleukin-6 overexpression discriminated rats that developed spontaneous PAH and rats that did not develop spontaneous PAH. Finally, detailed assessments of cardiomyocytes demonstrated alterations in morphology, calcium (Ca2+), and cell contractility specific to the right ventricle; these changes could explain the lower cardiac output of Δ 71 rats. Indeed, adult right ventricular cardiomyocytes from Δ 71 rats exhibited a smaller diameter, decreased sensitivity of sarcomeres to Ca2+, decreased [Ca2+] transient amplitude, reduced sarcoplasmic reticulum Ca2+ content, and short action potential duration compared with right ventricular cardiomyocytes from wild-type rats. CONCLUSIONS: We characterized the first Bmpr2 mutant rats and showed some of the critical cellular and molecular dysfunctions described in human PAH. We also identified the heart as an unexpected but potential target organ of Bmpr2 mutations. Thus, this new genetic rat model represents a promising tool to study the pathogenesis of PAH.

Radiologic Analysis of Surgically Treated Fractures of the Condylar Process by an Endoscopic-Assisted Transoral Approach.

PURPOSE: This study analyzed the radiologic outcomes of patients with unilateral mandibular condylar fractures treated with open reduction-internal fixation (ORIF) through a transoral approach. PATIENTS AND METHODS: In this retrospective study, the radiologic images of 40 patients who underwent open reduction-internal fixation through a transoral approach were presented to 2 independent examiners. All patients underwent the surgical procedure between January 2015 and December 2016 at the Department of Cranio-Maxillofacial Surgery at UniversitätsSpital Zürich and were included in a previous functional outcome study. The surgical results were analyzed and graded as poor, acceptable, or good. The examiners declared whether they would have made any intraoperative revisions if the radiologic information had been available. Finally, the examiners estimated the required duration of elastic intermaxillary fixation (IMF) from the radiologic images, which was compared with the actual duration. RESULTS: Fracture reduction was classified as good in 33 cases (82.5%), acceptable in 5 cases, and poor in 2 cases by one examiner and as good in 32 cases (80%), acceptable in 6 cases, and poor in 2 cases by the other examiner. The inter-rater reliability was determined to be good (Cohen κ = 0.92). Correct osteosynthesis placement was found in 19 cases by one examiner and in 21 cases by the other examiner, with good inter-rater reliability (κ = 0.8). Moderate inter-rater reliability (κ = 0.4) was found for the required duration of elastic IMF. Furthermore, the estimated elastic IMF duration matched the actual duration in fewer than half of the cases. CONCLUSIONS: It is feasible to achieve reliably good radiologic results when operating on condylar process fractures by a transoral approach with endoscopic assistance and angled instruments. Intraoperative 3-dimensional imaging enables instant quality control and prompts surgical revision if needed.

Does Zygomatic Complex Symmetry Differ Between Healthy Individuals and Surgically Treated Patients Using Intraoperative 3-Dimensional Cone Beam Computed Tomographic Imaging?

PURPOSE: Reconstruction of symmetry after zygomaticomaxillary complex (ZMC) fractures is essential for esthetic appearance as well as function. Therefore, this study aimed to analyze whether bony facial symmetry in patients surgically treated for unilateral ZMC fractures via intraoperative imaging differs from that of healthy individuals. PATIENTS AND METHODS: Retrospective and cross-sectional radiographic measurements of patients treated for unilateral ZMC fractures via intraoperative cone beam computed tomography (CBCT) were performed to evaluate the postoperative ZMC symmetry. The same number of healthy individuals without any history of midfacial trauma matched for age and gender served as the control group. Asymmetry of the ZMC was determined by measuring bilateral differences in the malar eminence position on CBCT. In addition, demographic statistics, etiology, and fracture type were analyzed. RESULTS: Analysis of 57 surgically treated patients and 57 healthy individuals with a mean age of 29 years was performed. No significant difference in the symmetry of the malar eminence position was observed between healthy individuals and patients treated for a unilateral ZMC fracture (P = .890). In one third of patients, corrections were needed after intraoperative CBCT control. CONCLUSIONS: The results of this study indicate that, on average, a ZMC asymmetry of 1.6 mm is observed in healthy individuals. Furthermore, the use of intraoperative CBCT for the treatment of dislocated ZMC fractures helps to achieve precise anatomic, symmetrical repositioning and is suggested to improve the quality of care.

Atrial natriuretic peptide regulates adipose tissue accumulation in adult atria.

The abundance of epicardial adipose tissue (EAT) is associated with atrial fibrillation (AF), the most frequent cardiac arrhythmia. However, both the origin and the factors involved in EAT expansion are unknown. Here, we found that adult human atrial epicardial cells were highly adipogenic through an epithelial-mesenchymal transition both in vitro and in vivo. In a genetic lineage tracing the WT1CreERT2+/-RosatdT+/- mouse model subjected to a high-fat diet, adipocytes of atrial EAT derived from a subset of epicardial progenitors. Atrial myocardium secretome induces the adipogenic differentiation of adult mesenchymal epicardium-derived cells by modulating the balance between mesenchymal Wingless-type Mouse Mammary Tumor Virus integration site family, member 10B (Wnt10b)/ß-catenin and adipogenic ERK/MAPK signaling pathways. The adipogenic property of the atrial secretome was enhanced in AF patients. The atrial natriuretic peptide secreted by atrial myocytes is a major adipogenic factor operating at a low concentration by binding to its natriuretic peptide receptor A (NPRA) receptor and, in turn, by activating a cGMP-dependent pathway. Hence, our data indicate cross-talk between EAT expansion and mechanical function of the atrial myocardium.

A volumetric assessment and follow-up of a granuloma gravidarum in the anterior maxilla.

AIM: Granuloma gravidarum (GG) is a benign lesion of the soft tissue. The aim of this technical note is the volumetric assessment and follow-up 3D measurement of a GG in the anterior maxilla. MATERIALS AND METHODS: A 35-year-old female patient who was 7 months pregnant was referred due to a soft tissue tumor in the papilla of tooth 21. A biopsy verified a pyogenic granuloma gravidarum. Initial and consecutive volumeatric measurements were made with an intraoral scanner during the patient's pregnancy and until 16 months postpartum. RESULTS: The volumetric assessment showed a continuous growth of the tumor and a consecutive volume reduction 16 months postpartum. In comparison with the level of the papilla of the contralateral incisor, there was an almost complete remission at the last follow-up. CONCLUSION: Intraoral scans can serve for the volumetric assessment of soft tissue tumors of the alveolar crest. Image superimposition enables the quantification of changes in morphology. This supports clinical follow-ups and enables the quantification of clinical observations.

Progression of excitation-contraction coupling defects in doxorubicin cardiotoxicity.

Cardiac failure is a common complication in cancer survivors treated with anthracyclines. Here we followed up cardiac function and excitation-contraction (EC) coupling in an in vivo doxorubicin (Dox) treated mice model (iv, total dose of 10 mg/Kg divided once every three days). Cardiac function was evaluated by echocardiography at 2, 6 and 15 weeks after the last injection. While normal at 2 and 6 weeks, ejection fraction was significantly reduced at 15 weeks. In order to evaluate the underlying mechanisms, we measured [Ca2+]i transients by confocal microscopy and action potentials (AP) by patch-clamp technique in cardiomyocytes isolated at these times. Three phases were observed: 1/depression and slowing of the [Ca2+]i transients at 2 weeks after treatment, with occurrence of proarrhythmogenic Ca2+ waves, 2/compensatory state at 6 weeks, and 3/depression on [Ca2+]i transients and cell contraction at 15 weeks, concomitant with in-vivo defects. These [Ca2+]i transient alterations were observed without cellular hypertrophy or AP prolongation and mirrored the sarcoplasmic reticulum (SR) Ca2+ load variations. At the molecular level, this was associated with a decrease in the sarcoplasmic reticulum Ca2+ ATPase (SERCA2a) expression and enhanced RyR2 phosphorylation at the protein kinase A (PKA, pS2808) site (2 and 15 weeks). RyR2 phosphorylation at the Ca2+/calmodulin dependent protein kinase II (CaMKII, pS2814) site was enhanced only at 2 weeks, coinciding with the higher incidence of proarrhythmogenic Ca2+ waves. Our study highlighted, for the first time, the progression of Dox treatment-induced alterations in Ca2+ handling and identified key components of the underlying Dox cardiotoxicity. These findings should be helpful to understand the early-, intermediate-, and late- cardiotoxicity already recorded in clinic in order to prevent or treat at the subclinical level.

Synergic PDE3 and PDE4 control intracellular cAMP and cardiac excitation-contraction coupling in a porcine model.

AIMS: Cyclic AMP phosphodiesterases (PDEs) are important modulators of the cardiac response to ß-adrenergic receptor (ß-AR) stimulation. PDE3 is classically considered as the major cardiac PDE in large mammals and human, while PDE4 is preponderant in rodents. However, it remains unclear whether PDE4 also plays a functional role in large mammals. Our purpose was to understand the role of PDE4 in cAMP hydrolysis and excitation-contraction coupling (ECC) in the pig heart, a relevant pre-clinical model. METHODS AND RESULTS: Real-time cAMP variations were measured in isolated adult pig right ventricular myocytes (APVMs) using a Förster resonance energy transfer (FRET) biosensor. ECC was investigated in APVMs loaded with Fura-2 and paced at 1 Hz allowing simultaneous measurement of intracellular Ca2+ and sarcomere shortening. The expression of the different PDE4 subfamilies was assessed by Western blot in pig right ventricles and APVMs. Similarly to PDE3 inhibition with cilostamide (Cil), PDE4 inhibition with Ro 20-1724 (Ro) increased cAMP levels and inotropy under basal conditions. PDE4 inhibition enhanced the effects of the non-selective ß-AR agonist isoprenaline (Iso) and the effects of Cil, and increased spontaneous diastolic Ca2+ waves (SCWs) in these conditions. PDE3A, PDE4A, PDE4B and PDE4D subfamilies are expressed in pig ventricles. In APVMs isolated from a porcine model of repaired tetralogy of Fallot which leads to right ventricular failure, PDE4 inhibition also exerts inotropic and pro-arrhythmic effects. CONCLUSIONS: Our results show that PDE4 controls ECC in APVMs and suggest that PDE4 inhibitors exert inotropic and pro-arrhythmic effects upon PDE3 inhibition or ß-AR stimulation in our pre-clinical model. Thus, PDE4 inhibitors should be used with caution in clinics as they may lead to arrhythmogenic events upon stress.

NMDA-Type Glutamate Receptor Activation Promotes Vascular Remodeling and Pulmonary Arterial Hypertension.

BACKGROUND: Excessive proliferation and apoptosis resistance in pulmonary vascular cells underlie vascular remodeling in pulmonary arterial hypertension (PAH). Specific treatments for PAH exist, mostly targeting endothelial dysfunction, but high pulmonary arterial pressure still causes heart failure and death. Pulmonary vascular remodeling may be driven by metabolic reprogramming of vascular cells to increase glutaminolysis and glutamate production. The N-methyl-d-aspartate receptor (NMDAR), a major neuronal glutamate receptor, is also expressed on vascular cells, but its role in PAH is unknown. METHODS: We assessed the status of the glutamate-NMDAR axis in the pulmonary arteries of patients with PAH and controls through mass spectrometry imaging, Western blotting, and immunohistochemistry. We measured the glutamate release from cultured pulmonary vascular cells using enzymatic assays and analyzed NMDAR regulation/phosphorylation through Western blot experiments. The effect of NMDAR blockade on human pulmonary arterial smooth muscle cell proliferation was determined using a BrdU incorporation assay. We assessed the role of NMDARs in vascular remodeling associated to pulmonary hypertension, in both smooth muscle-specific NMDAR knockout mice exposed to chronic hypoxia and the monocrotaline rat model of pulmonary hypertension using NMDAR blockers. RESULTS: We report glutamate accumulation, upregulation of the NMDAR, and NMDAR engagement reflected by increases in GluN1-subunit phosphorylation in the pulmonary arteries of human patients with PAH. Kv channel inhibition and type A-selective endothelin receptor activation amplified calcium-dependent glutamate release from human pulmonary arterial smooth muscle cell, and type A-selective endothelin receptor and platelet-derived growth factor receptor activation led to NMDAR engagement, highlighting crosstalk between the glutamate-NMDAR axis and major PAH-associated pathways. The platelet-derived growth factor-BB-induced proliferation of human pulmonary arterial smooth muscle cells involved NMDAR activation and phosphorylated GluN1 subunit localization to cell-cell contacts, consistent with glutamatergic communication between proliferating human pulmonary arterial smooth muscle cells via NMDARs. Smooth-muscle NMDAR deficiency in mice attenuated the vascular remodeling triggered by chronic hypoxia, highlighting the role of vascular NMDARs in pulmonary hypertension. Pharmacological NMDAR blockade in the monocrotaline rat model of pulmonary hypertension had beneficial effects on cardiac and vascular remodeling, decreasing endothelial dysfunction, cell proliferation, and apoptosis resistance while disrupting the glutamate-NMDAR pathway in pulmonary arteries. CONCLUSIONS: These results reveal a dysregulation of the glutamate-NMDAR axis in the pulmonary arteries of patients with PAH and identify vascular NMDARs as targets for antiremodeling treatments in PAH.

Outcome of Surgically Treated Fractures of the Condylar Process by an Endoscopic Assisted Transoral Approach.

PURPOSE: Fractures of the condylar process are frequent. Ideal management of these fractures, as discussed in the literature, is controversial. Some recent meta-analyses have favored open reduction and internal fixation using various approaches. A strictly transoral approach has been described to minimize scarring and risk of facial nerve injury but has restricted visibility. This retrospective study analyzed outcomes of patients with unilateral mandibular condyle fractures who were treated by open reduction and internal fixation through an endoscopic-assisted transoral approach. MATERIALS AND METHODS: This study included 40 patients who were operated on from January 2015 through December 2016. All patients underwent surgery for a condylar process fracture using an endoscopic-assisted transoral approach. Fracture classification, demographic, and outcome data were collected. RESULTS: Most condylar process fractures were caused by falls from a height less than 3 m. Most were condylar base fractures and classified according to Spiessl and Schroll as Classes I and II. Sixteen patients showed a preoperative malocclusion, whereas 2 patients showed a slight postoperative malocclusion. In cases in which only 1 plate could be placed, the proximal fragment was shorter. A higher Spiessl and Schroll class showed a tendency toward longer operation times. For postoperative outcomes, 1 case of temporary facial palsy was the worst complication (2.5%), 2 cases exhibited minimal occlusal interference (5%), and 1 case exhibited a deviated mouth opening (2.5%). Ramus height was restored in all cases. No chronic pain was found in any cases. CONCLUSIONS: It is feasible to treat condylar process fractures in a safe manner using a transoral approach with endoscopic assistance and angled instruments without facial scarring and at a low complication rate. The endoscope improves the restricted visibility of the transoral approach, although a learning curve is necessary. This applies especially to dislocated fractures or to fractures with a short proximal fragment.

Precision of Simultaneous Guided Dental Implantation in Microvascular Fibular Flap Reconstructions With and Without Additional Guiding Splints.

PURPOSE: Dental rehabilitation in patients receiving free flap reconstructive surgery on the mandible or maxilla is an important part of bringing patients back to normality in both a physical and psychological way. It is therefore important to be able to do this in the fastest way possible. Virtual preplanned reconstructions of jaws with implants placed simultaneously are a good way to expedite this process and have the advantage of allowing true backward planning to achieve bone placement where it prosthetically needs to be. Thus, the precise transfer of the virtually preplanned implant position to the intraoperative situation is crucial for prosthetic rehabilitation. PATIENTS AND METHODS: We compared a control group of patients (4 patients with 15 implants) with preplanned fibular reconstructions of the mandible with implants incorporated in the planning and a trial group of patients (4 patients with 13 implants) with an additional intraoperative splint for the verification of the implants' angulation. The preoperative planning and postoperative computed tomography scans were compared. RESULTS: The average positioning error at bone level was 0.9 mm in the trial group and 1.3 mm in the control group. The average angulation error in the buccolingual plane was 2.9° in the trial group and 5.5° in the control group; axially, the difference was 6.3° in the trial group and 4.1° in the control group. CONCLUSIONS: The use of digitally backward-planned fibula cutting guides with direct dental implant positioning is feasible, and the precision found is comparable with that of standard splint-guided implant placement in the general population. Although the axial angulation error has more to do with anatomic variance and positioning of the bony cutting guide, the trial population clearly profited from the additional splint in the important buccolingual angulation. Overall, we showed a high level of precision over all implants in both groups.

Accuracy of Computer-Guided Template-Based Implant Surgery: A Computed Tomography-Based Clinical Follow-Up Study.

OBJECTIVE: The aim of this clinical study was to analyze the accuracy of computer-guided implant surgery. MATERIALS AND METHODS: Assisted by computed tomography (CT)-based planning software and navigational templates, 16 patients successfully received 26 dental implants. Each implant parameter (a-d) was calculated based on superimposed preoperative and postoperative cone beam CT scans: (a) deviation at entry point; (b) deviation at apex; (c) angular deviation; and (d) depth deviation. RESULTS: Mean central deviation at implant entry point and apex was 0.91 mm (standard error [SE] = 0.11 mm; 95% confidence interval [CI]: 0.69-1.13) and 1.22 mm (SE = 0.11 mm; 95% CI: 0.99-1.45), respectively. Mean angulation deviation was 4.11 degrees (SE = 0.52 degrees; 95% CI: 3.04-5.17) and the average depth deviation was 0.65 mm (SE = 0.11 mm; 95% CI: 0.42-0.87). For the total number of implants placed, the maximum error was 2.34 mm at entry point, 2.71 mm at apex, 9.44 degrees in angular deviation, and 2.00 mm in depth deviation. CONCLUSION: Great accuracy was reached even in advanced cases with prior bone augmentation and complex traumas. This leads to the conclusion that particularly in advanced cases, computer-guided implantation can be beneficial.

Inducible Cardiac-Specific Deletion of Sirt1 in Male Mice Reveals Progressive Cardiac Dysfunction and Sensitization of the Heart to Pressure Overload.

Heart failure is associated with profound alterations of energy metabolism thought to play a major role in the progression of this syndrome. SIRT1 is a metabolic sensor of cellular energy and exerts essential functions on energy metabolism, oxidative stress response, apoptosis, or aging. Importantly, SIRT1 deacetylates the peroxisome proliferator-activated receptor gamma co-activator 1α (PGC-1α), the master regulator of energy metabolism involved in mitochondrial biogenesis and fatty acid utilization. However, the exact role of SIRT1 in controlling cardiac energy metabolism is still incompletely understood and conflicting results have been obtained. We generated a cardio-specific inducible model of Sirt1 gene deletion in mice (Sirt1ciKO) to decipher the role of SIRT1 in control conditions and following cardiac stress induced by pressure overload. SIRT1 deficiency induced a progressive cardiac dysfunction, without overt alteration in mitochondrial content or properties. Sixteen weeks after Sirt1 deletion an increase in mitochondrial reactive oxygen species (ROS) production and a higher rate of oxidative damage were observed, suggesting disruption of the ROS production/detoxification balance. Following pressure overload, cardiac dysfunction and alteration in mitochondrial properties were exacerbated in Sirt1ciKO mice. Overall the results demonstrate that SIRT1 plays a cardioprotective role on cardiac energy metabolism and thereby on cardiac function.

The BET Bromodomain Inhibitor I-BET-151 Induces Structural and Functional Alterations of the Heart Mitochondria in Healthy Male Mice and Rats.

The bromodomain and extra-terminal domain family inhibitors (BETi) are a promising new class of anticancer agents. Since numerous anticancer drugs have been correlated to cardiomyopathy, and since BETi can affect non-cancerous tissues, we aimed to investigate in healthy animals any ultrastructural BETi-induced alterations of the heart as compared to skeletal muscle. Male Wistar rats were either treated during 3 weeks with I-BET-151 (2 or 10 mg/kg/day) (W3) or treated for 3 weeks then allowed to recover for another 3 weeks (W6) (3-weeks drug washout). Male C57Bl/6J mice were only treated during 5 days (50 mg/kg/day). We demonstrated the occurrence of ultrastructural alterations and progressive destruction of cardiomyocyte mitochondria after I-BET-151 exposure. Those mitochondrial alterations were cardiac muscle-specific, since the skeletal muscles of exposed animals were similar in ultrastructure presentation to the non-exposed animals. I-BET-151 decreased the respiration rate of heart mitochondria in a dose-dependent manner. At the higher dose, it also decreased mitochondrial mass, as evidenced by reduced right ventricular citrate synthase content. I-BET-151 reduced the right and left ventricular fractional shortening. The concomitant decrease in the velocity-time-integral in both the aorta and the pulmonary artery is also suggestive of an impaired heart function. The possible context-dependent cardiac side effects of these drugs have to be appreciated. Future studies should focus on the basic mechanisms of potential cardiovascular toxicities induced by BETi and strategies to minimize these unexpected complications.

Guided apicoectomy using a CAD/CAM drilling template.

AIM: Modern microsurgical techniques have increased the success rate of apicoectomy relative to that of traditional approaches. This case report introduces a novel workaround for guided apicoectomy using a patient-specific computer-aided design/computer-aided manufacturing (CAD/CAM) three-dimensional (3D)-printed template. MATERIALS AND METHODS: Apicoectomy was performed on the mesial root of tooth 36 using template-guided trephine drilling, followed by retrograde filling with mineral trioxide aggregate (MTA). Initially, a cone beam computed tomography (CBCT) scan and an intraoral surface scan were imported into the planning software. After superimposition, virtual planning was performed to determine the exact localization for root resection. Subsequently, a tooth-supported drilling template was designed and 3D printed. Endodontic microsurgical approaches, including root-end cavity preparation and root-end filling, completed the surgical treatment. RESULT: The apical resection was easily feasible. There were no postoperative complications. Radiological assessment after a 6-month period showed signs of reossification. CONCLUSION: Guided apicoectomy allowed precise root resection, suggesting that this technique may be advantageous in complex anatomical situations.

Ca2+ handling remodeling and STIM1L/Orai1/TRPC1/TRPC4 upregulation in monocrotaline-induced right ventricular hypertrophy.

BACKGROUND: Right ventricular (RV) function is the most important prognostic factor for pulmonary arterial hypertension (PAH) patients. The progressive increase of pulmonary vascular resistance induces RV hypertrophy (RVH) and at term RV failure (RVF). However, the molecular mechanisms of RVH and RVF remain understudied. In this study, we gained insights into cytosolic Ca2+ signaling remodeling in ventricular cardiomyocytes during the pathogenesis of severe pulmonary hypertension (PH) induced in rats by monocrotaline (MCT) exposure, and we further identified molecular candidates responsible for this Ca2+ remodeling. METHODS AND RESULTS: After PH induction, hypertrophied RV myocytes presented longer action potential duration, higher and faster [Ca2+]i transients and increased sarcoplasmic reticulum (SR) Ca2+ content, whereas no changes in these parameters were detected in left ventricular (LV) myocytes. These modifications were associated with increased P-Ser16-phospholamban pentamer expression without altering SERCA2a (Sarco/Endoplasmic Reticulum Ca2+-ATPase) pump abundance. Moreover, after PH induction, Ca2+ sparks frequency were higher in hypertrophied RV cells, while total RyR2 (Ryanodine Receptor) expression and phosphorylation were unaffected. Together with cellular hypertrophy, the T-tubules network was disorganized. Hypertrophied RV cardiomyocytes from MCT-exposed rats showed decreased expression of classical STIM1 (Stromal Interaction molecule) associated with increased expression of muscle-specific STIM1 Long isoform, glycosylated-Orai1 channel form, and TRPC1 and TRPC4 channels, which was correlated with an enhanced Ca2+-release-activated Ca2+ (CRAC)-like current. Pharmacological inhibition of TRPCs/Orai1 channels in hypertrophied RV cardiomyocytes normalized [Ca2+]i transients amplitude, the SR Ca2+ content and cell contractility to control levels. Finally, we showed that most of these changes did not appear in LV cardiomyocytes. CONCLUSIONS: These new findings demonstrate RV-specific cellular Ca2+ cycling remodeling in PH rats with maladaptive RVH and that the STIM1L/Orai1/TRPC1/C4-dependent Ca2+ current participates in this Ca2+ remodeling in RVH secondary to PH.