Accuracy and efficiency of automatic tooth segmentation in digital dental models using deep learning.

This study evaluates the accuracy and efficiency of automatic tooth segmentation in digital dental models using deep learning. We developed a dynamic graph convolutional neural network (DGCNN)-based algorithm for automatic tooth segmentation and classification using 516 digital dental models. We segmented 30 digital dental models using three methods for comparison: (1) automatic tooth segmentation (AS) using the DGCNN-based algorithm from LaonSetup software, (2) landmark-based tooth segmentation (LS) using OrthoAnalyzer software, and (3) tooth designation and segmentation (DS) using Autolign software. We evaluated the segmentation success rate, mesiodistal (MD) width, clinical crown height (CCH), and segmentation time. For the AS, LS, and DS, the tooth segmentation success rates were 97.26%, 97.14%, and 87.86%, respectively (p < 0.001, post-hoc; AS, LS > DS), the means of MD widths were 8.51, 8.28, and 8.63 mm, respectively (p < 0.001, post hoc; DS > AS > LS), the means of CCHs were 7.58, 7.65, and 7.52 mm, respectively (p < 0.001, post-hoc; LS > DS, AS), and the means of segmentation times were 57.73, 424.17, and 150.73 s, respectively (p < 0.001, post-hoc; AS < DS < LS). Automatic tooth segmentation of a digital dental model using deep learning showed high segmentation success rate, accuracy, and efficiency; thus, it can be used for orthodontic diagnosis and appliance fabrication.

MicroRNA-552 expression in colorectal cancer and its clinicopathological significance.

BACKGROUND: MicroRNA-552 (miR-552) has been reported to correlate with the development and progression of various cancers, including colorectal cancer (CRC). This study aimed to investigate miR-552 expression in cancer tissue samples compared to normal mucosal tissue and its role as a diagnostic or prognostic marker in CRC patients. METHODS: Normal mucosal tissues and primary cancer tissues from 80 surgically resected CRC specimens were used. Quantitative real-time polymerase chain reaction was performed for miR-552 and U6 small nuclear RNA to analyze miR-552 expression and its clinicopathological significance. Immunohistochemistry for p53 and phosphatase and tension homolog (PTEN) was performed to evaluate their association with miR-552 expression. RESULTS: miR-552 expression was significantly higher in primary cancer tissues compared to normal mucosal tissues (p<.001). The expression level of miR552 was inversely correlated with that of PTEN (p=.068) and p53 (p=.004). Survival analysis showed that high miR-552 expression was associated with worse prognosis but this was not statistically significant (p=.255). However, patients with CRC having high miR-552 expression and loss of PTEN expression had significantly worse prognosis than others (p=.029). CONCLUSIONS: Our results suggest that high miR-552 expression might be a potential diagnostic biomarker for CRC, and its combined analysis with PTEN expression can possibly be used as a prognostic marker.

Woohwangcheongsimwon Prevents High-Fat Diet-Induced Memory Deficits and Induces SIRT1 in Mice.

Woohwangcheongsimwon (WHC) is a mixture of herbal medicines that is widely prescribed in Korean traditional medicine. SIRT1 is known for its regulatory roles in energy metabolism, oxidative stress, and circadian rhythms. This study was designed to determine whether WHC can increase and mimic the biological reactions of SIRT1 activation. Ten-month-old male mice were divided into four groups: nontreated normal diet (ND), nontreated high-fat diet (HFD), WHC-treated ND, and WHC-treated HFD. Body weight and cognitive functions were evaluated after treatment. The hippocampal expressions of SIRT1 and PGC-1α were also measured. The components of WHC were identified by liquid chromatography. High-fat diet-fed mice gained more weight and demonstrated greater deficits in short-term and long-term cognitive functions. WHC suppressed the deleterious effects of a HFD on weight gain and cognitive decline, but showed no prominent effects on animals fed NDs. The herbal treatment also increased the expression of SIRT1 and PGC-1α in the hippocampus. Despite the induction of hippocampal SIRT1 expression by WHC, resveratrol was not present among the natural compounds identified. This expression might have contributed to the suppression of high-fat diet-induced memory deficits in mice treated with the herbal mixture.

Canine Hepatitis Associated with Intrahepatic Bacteria in Three Dogs.

This case report describes the detection of intrahepatic bacteria in formalin-fixed paraffin-embedded histopathological sections from three dogs with neutrophilic, pyogranulomatous, or lymphoplasmacytic hepatitis and cholangiohepatitis. In each of these cases, eubacterial fluorescence in situ hybridization enabled colocalization of intrahepatic bacteria with neutrophilic and granulomatous inflammation in samples that were negative for bacteria when evaluated by routine hematoxylin and eosin histopathology augmented with histochemical stains. Positive responses to antimicrobial therapy were observed in of 2 out of 2 patients that were treated with antimicrobials. These findings suggest that eubacterial fluorescence in situ hybridization analysis of formalin-fixed paraffin-embedded histopathological sections is more sensitive than conventional histochemical stains for the diagnosis of bacteria-associated canine hepatitis.

Gastric Dilatation Associated with Gastric Colonization with Sarcina-Like Bacteria in a Cat with Chronic Enteritis.

An 11 yr old spayed female domestic longhair cat was presented for an acute onset of vomiting. Abdominal radiographs and ultrasound revealed severe gastric dilatation (GD) without evidence of gastric outflow obstruction. On esophagogastroduodenoscopy, the duodenal mucosa was mildly erythematous, and a moderate, diffuse, chronic enteritis was found by histological examination of duodenal biopsies. Large numbers of Sarcina-like bacteria without associated inflammation were present in gastric mucosal biopsies. To the authors' knowledge, this is the first report of GD associated with colonization by Sarcina-like bacteria in a cat. Gastric colonization by Sarcina-like bacteria should be suspected when cats are presented with acute onset of GD and vomiting.

Surgery-first approach using a three-dimensional virtual setup and surgical simulation for skeletal Class III correction.

A 19-year-old woman presented to our dental clinic with anterior crossbite and mandibular prognathism. She had a concave profile, long face, and Angle Class III molar relationship. She showed disharmony in the crowding of the maxillomandibular dentition and midline deviation. The diagnosis and treatment plan were established by a three-dimensional (3D) virtual setup and 3D surgical simulation, and a surgical wafer was produced using the stereolithography technique. No presurgical orthodontic treatment was performed. Using the surgery-first approach, Le Fort I maxillary osteotomy and mandibular bilateral intraoral vertical ramus osteotomy setback were carried out. Treatment was completed with postorthodontic treatment. Thus, symmetrical and balanced facial soft tissue and facial form as well as stabilized and well-balanced occlusion were achieved.

Comparison of virtual and manual tooth setups with digital and plaster models in extraction cases.

INTRODUCTION: The aim of this study was to compare the virtual and manual tooth setups with digital and plaster models in extraction cases by measuring various occlusal parameters and applying the American Board of Orthodontics objective grading system. METHODS: Linear intra-arch and interarch dimensions (arch width and length, perimeter, overjet, and overbite), angular variables (tip, torque, and rotation), and American Board of Orthodontics objective grading system scores obtained from a digital virtual setup model were compared with those from a plaster model setup. RESULTS: The digital virtual setup model resulted in smaller arch perimeters than did the plaster setup model by 2.20 mm in the maxillary arch (P <0.01) and 1.30 mm in the mandibular arch (P <0.05). The digital virtual setup also exhibited significantly lower values for overbite and overjet (P <0.01). The digital virtual setup had tendencies toward mesial angulation of the anterior teeth, labial inclination of the maxillary anterior teeth (P <0.05), and distal in-rotation of the mandibular teeth (P <0.05). The resulting American Board of Orthodontics objective grading system evaluation showed that larger deductions for overjet, occlusal contact, and total score (P <0.01) were required for the digital than for the manual setup model. CONCLUSIONS: Digital and manual setups lead to similar measurements for intra-arch and interarch occlusal variables. However, because of the possibility of collision on proximal and occlusal contact, delicate adjustments in proximal and occlusal contacts are required.

Effects of fixation and storage of human tissue samples on nucleic Acid preservation.

BACKGROUND: Because of recent advances in the molecular diagnosis of cancer patients, tissue quality has become more important in daily practice. METHODS: To evaluate the effects of fixative, duration of fixation, decalcification, and storage periods on nucleic acid integrity, DNA and RNA were extracted from gastrointestinal cancer tissue. The yield and purity were analyzed, and polymerase chain reaction (PCR) for glyceraldehyde 3-phosphate dehydrogenase (GAPDH; 60 bp), ß-actin (148 bp), and human growth hormone (hGH; 434 bp) and real-time reverse transcription-PCR for ß-actin (97 bp) were performed. RESULTS: All formalin-fixed paraffin-embedded (FFPE) and methacarn-fixed paraffin-embedded (MFPE) samples tested positive for GAPDH and ß-actin by PCR. hGH was successfully detected in all MFPE samples, but in only 46.7% of the FFPE samples. Prolonged formalin fixation resulted in fewer GAPDH and ß-actin PCR products, and amplification of hGH was not successful. The PCR and reverse transcription-PCR results were significantly affected by the duration of decalcification. The yield, purity, and integrity of mRNA progressively decreased with increased storage periods of paraffin blocks. CONCLUSIONS: Fixation and storage should therefore be standardized in order to improve the quality of molecular pathologic diagnosis.

Preclinical evidence of rapid-onset antidepressant-like effect in Radix Polygalae extract.

Radix Polygalae (the root of Polygala tenuifolia) is a herb widely used in traditional Asian medicine that is thought to exert a variety of neuropsychiatric effects. Radix Polygalae extract can protect against N-methyl D-aspartate (NMDA) neurotoxicity and induce brain-derived neurotrophic factor (BDNF) expression, suggesting modulatory roles at glutamatergic synapses and possible antidepressant action. In accordance with this hypothesis, Radix Polygalae extract demonstrated antidepressant-like effects in 8-week-old male C57Bl/6 mice by decreasing behavioral despair in the forced swim and tail suspension tasks and increasing hedonic-like behavior in the female urine sniffing test 30 minutes after a single oral administration of 0.1 mg/kg. Reduced latency to acquire a food pellet in the novely suppressed feeding paradigm, without change in anxiety-like behaviors suggested a rapid-onset nature of the antidepressant-like effect. In addition, it decreased the number of failed escapes in the learned helplessness paradigm after two oral administrations 24 hours and 30 minutes before the first test. Finally, it reversed anhedonia as measured by saccharin preference in mice exposed to the chronic stress model after two administrations of 0.1 mg/kg, in contrast to the repeated administration generally needed for similar effect by monoamergic antidepressants. Immobility reduction in tail suspension task was blocked by the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist NBQX, a pattern previously demonstrated by ketamine and other ketamine-like rapid-onset antidepressants. Also similarly to ketamine, Radix Polygalae appeared to acutely decrease phosphorylation of GluR1 serine-845 in the hippocampus while leaving the phosphorylation of hippocampal mTOR serine 2448 unchanged. These findings serve as preclinical evidence that Radix Polygalae extract exerts rapid-onset antidepressant effects by modulating glutamatergic synapses in critical brain circuits of depression and may be worthy of further evaluation as a safe substitute to other rapid-onset antidepressants known to have unacceptable side effects.

Tangent hyperplane kernel principal component analysis for denoising.

Kernel principal component analysis (KPCA) is a method widely used for denoising multivariate data. Using geometric arguments, we investigate why a projection operation inherent to all existing KPCA denoising algorithms can sometimes cause very poor denoising. Based on this, we propose a modification to the projection operation that remedies this problem and can be incorporated into any of the existing KPCA algorithms. Using toy examples and real datasets, we show that the proposed algorithm can substantially improve denoising performance and is more robust to misspecification of an important tuning parameter.

The Role of Oxygen-Derived Free Radicals in Vascular Relaxations to Pinacidil in Renal Hypertensive Rats / 대한신장학회지

PURPOSE: Evidence has emerged that oxygen-derived free radicals may induce vascular relaxations via ATP-sensitive K+ (K(ATP)) channels and the level of free radicals is increased in animal models of hypertension. The present study was conducted to determine whether relaxations to an K(ATP) channel opener, pinacidil, are increased in the aorta from two-kidney, one clip (2K1C) hypertensive rats and whether free radial scavengers reduce these relaxations. METHODS: 2K1C hypertension was induced by clipping the left renal artery and age-matched control rats received a sham treatment. Rings of aortae without endothelium were suspended for isometric force recording. RESULTS: Relaxations to pinacidil (10(-8) to 10(-5) M), which are abolished by glibenclamide (10(-5) M), were augmented in the aorta from 2K1C rats, compared to those from control rats. In the aorta from 2K1C rats, catalase (1,200 U/mL), but neither superoxide dismutase (150 U/mL) nor deferoxamine (10(-4) M), reduced relaxations to pinacidil, whereas in the aorta from control rats, the free radical scavengers did not affect these relaxations. CONCLUSION: These results suggest that in 2K1C hypertension, vasorelaxation to an KATP channel opener is augmented and that hydrogen peroxide in smooth muscle cells may partly contribute to these relaxations.