Detection of oral cancer and oral potentially malignant disorders using artificial intelligence-based image analysis.

BACKGROUND: We aimed to construct an artificial intelligence-based model for detecting oral cancer and dysplastic leukoplakia using oral cavity images captured with a single-lens reflex camera. SUBJECTS AND METHODS: We used 1043 images of lesions from 424 patients with oral squamous cell carcinoma (OSCC), leukoplakia, and other oral mucosal diseases. An object detection model was constructed using a Single Shot Multibox Detector to detect oral diseases and their locations using images. The model was trained using 523 images of oral cancer, and its performance was evaluated using images of oral cancer (n = 66), leukoplakia (n = 49), and other oral diseases (n = 405). RESULTS: For the detection of only OSCC versus OSCC and leukoplakia, the model demonstrated a sensitivity of 93.9% versus 83.7%, a negative predictive value of 98.8% versus 94.5%, and a specificity of 81.2% versus 81.2%. CONCLUSIONS: Our proposed model is a potential diagnostic tool for oral diseases.

A case of synchronous double cancers consisting of maxillary gingival carcinoma and intraductal papillary mucinous carcinoma, invasive: case report.

BACKGROUND: The development of synchronous multiple primary cancers is one of the major causes of death in patients with head and neck cancer. Herein, we report a case of synchronous intraductal papillary mucinous carcinoma (IPMC), invasive in a patient with maxillary gingival carcinoma. CASE PRESENTATION: A 73-year-old female visited our hospital complaining of a mass on the left side of the maxillary gingiva. Intraorally, an exophytic tumor, 50 × 25 mm in size, was found on the gingiva of the left maxillary posterior, and a diagnosis of squamous cell carcinoma was revealed by cytology. Emission tomography/ computed tomography with 18 Fluorodeoxyglucose-Positron (18FDG- PET/ CT) showed increased accumulation in the left maxillary gingiva, the left side of cervical lymph nodes, and the main pancreatic duct. The pancreatic ductal tumor was performed the biopsy at esophagogastroduodenoscopy (EGD) and resulted in a pathological diagnosis of IPMC, invasive. The patient was diagnosed as synchronous double primary cancers consisting of maxillary gingival carcinoma cT4aN2bM0 and IPMC, invasive cT3N0M0. She refused radical treatment, and died 11 months later. CONCLUSION: 18FDG- PET/ CT, EGD and multidisciplinary approach is required for the detection and determining the treatment strategy of synchronous double primary cancers.

A case of giant dental calculus in a patient with centronuclear myopathy.

INTRODUCTION: Centronuclear myopathy is a hereditary congenital muscle disease. It is characterized by generalized muscle hypotonia from early childhood, elongated cacial appearance, mandibular undergroth, and dental malposition. In this report, we discuss the clinical course and management of a patient with centronuclearmyopathy, who developed a giant dental calculus in the floor of the mouth and underwent surgical excision. CASE REPORT: A 37-year-old Japanese man was referred to our hospital, and reported a swelling in the floor of the mouth. The patient affects centronuclear myopathy and has generalized muscle weakness. CT images showed a high-density area in the floor of the mouth measuring 35 × 28 × 20 mm. The lesion was clinically diagnosed as giant dental calculus, and surgically removed. CONCLUSION: We have experienced a case of giant dental calculus in a patient with centronuclear myopathy. In dental treatment, we must consider generalized muscle weakness.

Involvement of distant octacalcium phosphate scaffolds in enhancing early differentiation of osteocytes during bone regeneration.

This study hypothesized that distant octacalcium phosphate (OCP) scaffolds may enhance osteocyte differentiation in newly formed bone matrices. The results obtained were compared with those of Ca-deficient hydroxyapatite (OCP hydrolyzate, referred to as HL hereafter). Granular OCP and HL, 300-500 µm in diameter, were implanted in critical-sized rat calvarial defects for eight weeks and subjected to histology, immunohistochemistry, histomorphometry, and transmission electron microscopy (TEM). Early osteocyte differentiation from an osteoblastic cell line (IDG-SW3) was examined using materials without contacting the surfaces for 10 days. The material properties and the medium composition were analyzed through selected area electron diffraction (SAED) using TEM observation and curve fitting of Fourier transform infrared (FT-IR) spectroscopy. The number of positive cells of an osteocyte earlier differentiation marker podoplanin (PDPN) in bone matrices, along the direction of bone formation, was significantly higher in OCP than that in HL. The ultrastructure around the OCP surfaces observed by TEM showed the infiltration of some cells, including osteocytes adjacent to the OCP surface layers. The OCP structure remained unchanged by SAED analysis. Nanoparticle deposition and hydrolysis on OCP surfaces were detected by TEM and FT-IR, respectively, during early osteocyte differentiation in vitro. The medium saturation degree varied in accord with ionic dissolution, resulting in possible hydroxyapatite formation on OCP but not on HL. These results suggested that OCP stimulates early osteocyte differentiation in the bone matrix from a distance through its metastable chemical properties. STATEMENT OF SIGNIFICANCE: This study demonstrated that octacalcium phosphate (OCP) implanted in critical-sized rat calvaria bone defects is capable of enhancing the early differentiation of osteocytes embedded in newly formed bone matrices, even when the surface OCP is separated from the osteocytes. This prominent bioactive property of OCP was demonstrated by comparing the in vivo and in vitro performances with a control material, Ca-deficient hydroxyapatite (OCP hydrolyzate). The findings were elucidated by histomorphometry, which analyzed the differentiation of osteocytes along the parallel direction of new bone growth by osteoblasts. Therefore, OCP should stimulate osteocyte differentiation through ionic dissolution even in vivo owing to its metastable chemical properties, as previously reported in an in vitro study (Acta Biomater 69:362, 2018).

Osteogenic cellular activity around onlaid octacalcium phosphate-gelatin composite onto rat calvaria.

The activity and the distribution of osteogenic cells around octacalcium phosphate (OCP) granules combined with gelatin matrix (OCP/Gel) onlaid on rat calvaria were analyzed histomorphometrically and immunohistochemically during vertical bone augmentation under mechanical or nonmechanical environment until 8 weeks. OCP/Gel disk was placed in subperiosteal pocket on the calvaria with or without polytetrafluoroethylene (PTFE) support. The latter is a nonmechanical stress model to alleviate the mechanical stress from the subcutaneous tissues. Onlay grafts of gelatin (Gel) sponge disk and OCP granules were also carried out for the comparison purpose. When bone augmentation was evaluated in first area from bone surface (area until 150 µm high from bone surface) and second area above the newly formed bone (area until 150 µm high from the first area), bone formation was enhanced most in first area followed by second area of OCP/Gel with PTFE. The appearance of tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like cells was suppressed more in the newly formed tissue with PTFE than those without PTFE with an emphasis of the presence of gelatin. Although Runx2 positive-cells were accumulated more in both OCP/Gel with and without PTFE, osteocalcin-positive cells were abundant in OCP/Gel with PTFE than that without PTFE, suggesting that nonmechanical stress condition is more suitable for osteoblast differentiation. The appearance of receptor activator of nuclear factor (NF)-kappaB ligand (RANKL)-positive cells was restrained in OCP/Gel and Gel with PTFE while osteoprotegerin-positive cells were most accumulated in OCP/Gel without PTFE. The results suggest that OCP/Gel composite under the mechanical stress-alleviated condition can enhance bone augmentation through balanced osteoblastic and osteoclastic cellular activities. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1322-1333, 2018.

Relationship between cortical bone thickness and implant stability at the time of surgery and secondary stability after osseointegration measured using resonance frequency analysis.

PURPOSE: It has been suggested that resonance frequency analysis (RFA) can measure changes in the stability of dental implants during osseointegration. This retrospective study aimed to evaluate dental implant stability at the time of surgery (primary stability; PS) and secondary stability (SS) after ossseointegration using RFA, and to investigate the relationship between implant stability and cortical bone thickness. METHODS: In total, 113 patients who attended the Tohoku University Hospital Dental Implant Center were included in this study. A total of 229 implants were placed in either the mandibular region (n=118) or the maxilla region (n=111), with bone augmentation procedures used in some cases. RFA was performed in 3 directions, and the lowest value was recorded. The preoperative thickness of cortical bone at the site of implant insertion was measured digitally using computed tomography, excluding cases of bone grafts and immediate implant placements. RESULTS: The mean implant stability quotient (ISQ) was 69.34±9.43 for PS and 75.99±6.23 for SS. The mandibular group had significantly higher mean ISQ values than the maxillary group for both PS and SS (P<0.01). A significant difference was found in the mean ISQ values for PS between 1-stage and 2-stage surgery (P<0.5). The mean ISQ values in the non-augmentation group were higher than in the augmentation group for both PS and SS (P<0.01). A weak positive correlation was observed between cortical bone thickness and implant stability for both PS and SS in all cases (P<0.01). CONCLUSIONS: Based on the present study, the ISQ may be affected by implant position site, the use of a bone graft, and cortical bone thickness before implant therapy.

Estimation of glomerular filtration rate in dogs by a single-blood sample method involving iodixanol.

OBJECTIVE: To establish a simplified single-blood-sample method (SBSM) involving iodixanol to estimate glomerular filtration rate (GFR) in dogs and compare data provided by that procedure with data provided by a conventional multiple-blood-sample method (MBSM) involving inulin. ANIMALS: 26 healthy dogs and 36 dogs with naturally occurring renal disease. PROCEDURES: Dogs were used in various preliminary experiments to establish protocols for the SBSM and the MBSM of GFR estimation. To evaluate the relationship between GFRs obtained by the SBSM and the MBSM each involving iodixanol, iodixanol (40 mg of I/kg) was administered IV to 26 healthy dogs and 36 dogs with renal disease; blood sample collection was performed before and at 60, 90, and 120 minutes after the injection. To evaluate the relationship between GFRs obtained by the SBSM involving iodixanol and the MBSM involving inulin, iodixanol (40 mg of I/kg) and inulin (50 mg/kg) were coadministered IV to 22 healthy dogs and 3 dogs with renal disease, followed by blood sample collection 30, 60, 90, and 120 minutes later. Serum iodixanol and inulin concentrations were separately determined by reverse-phase high-performance liquid chromatography. RESULTS: Findings revealed a correlation (r = 0.99) between GFR estimated by the SBSM and MBSM each involving iodixanol. Likewise, GFR estimated by the SBSM involving iodixanol was correlated (r = 0.89) with that estimated by the MBSM involving inulin. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the SBSM involving iodixanol can be applied to estimate GFR in dogs, instead of use of an MBSM.

Relationship of glomerular filtration rate based on serum iodixanol clearance to IRIS staging in cats with chronic kidney disease.

We examined the correlation between the glomerular filtration rate (GFR) estimated from an equation based on the serum iodixanol clearance technique and International Renal Interest Society (IRIS) stages of chronic kidney disease (CKD) in cats. The equation included the injection dose, sampling time, serum concentration and estimated volume of distribution (Vd) of the isotonic, nonionic, contrast medium iodixanol as a test tracer. The percent changes in the median basal GFR values calculated from the equation in CKD cats resembled those of IRIS stages 1-3. These data validate the association between the GFR derived from the simplified equation and IRIS stages based on the serum creatinine concentration in cats with CKD. They describe the GFR ranges determined using single-sample iodixanol clearance for healthy cats and cats with various IRIS stages of CKD.

Glomerular filtration rate in cows estimated by a prediction formula.

To testify the relevance of Jacobsson's equation for estimating bovine glomerular filtration rate (GFR), we prepared an integrated formula based on its equation using clinically healthy dairy (n=99) and beef (n=63) cows, and cows with reduced renal function (n=15). The isotonic, nonionic, contrast medium iodixanol was utilized as a test tracer. The GFR values estimated from the integrated formula were well consistent with those from the standard multisample method in each cow strain, and the Holstein equation prepared by a single blood sample in Holstein dairy cows. The basal reference GFR value in healthy dairy cows was significantly higher than that in healthy beef cows, presumably due to a breed difference or physiological state difference. It is concluded that the validity for the application of Jacobsson's equation to estimate bovine GFR is proven and it can be used in bovine practices.

Estimation of glomerular filtration rate in conscious mice using a simplified equation.

To develop an expedient procedure for estimating glomerular filtration rate (GFR) in conscious mice, we first established a simple technique for repeated blood collections from the tail vein using a microcapillary tube attached to a 24-gauge needle without the hub. Then, we devised a definition equation for estimation of the GFR using the contrast medium iodixanol as a test tracer. Iodixanol was administered as a bolus injection at 1500 mg I/kg to ddY mice, and the GFR was determined by the conventional multisample strategy. Based on cumulative data from the multisample method, an equation for the single-blood-sample method including the iodixanol dose, estimated distribution volume (Vd), and plasma iodixanol concentration at 60 min later was sought. The GFR values from the multisample method were in good agreement with those calculated using the equation. In clinically healthy mice, the GFR decreased gradually with ages from 11 weeks old in both sexes, suggesting the necessity of the corresponding control in each protocol. In nephropathy mice induced by cisplatin, the GFR values decreased with rises in serum BUN and creatinine concentrations, and serum creatinine became elevated when the GFR decreased to approximately 70% of the basal value. The results suggest that the simplified equation using iodixanol, allowing for the repeated use of the same mice, is a versatile procedure for research purposes.

Estimation of glomerular filtration rate in cynomolgus monkeys (Macaca fascicularis).

To estimate the glomerular filtration rate (GFR) in cynomolgus monkeys (Macaca fascicularis), a three-blood-sample method using iodixanol was assessed in comparison with the conventional multisample strategy using inulin. Iodixanol and inulin were coadministered intravenously 40 mg I/kg and 50 mg/kg, respectively, to male monkeys, followed by blood collection 60, 90 and 120 min later. A close correlation (r=0.96) was noted between the GFR values estimated by both methods. In clinically healthy monkeys, the basal values were determined to be 3.06 ± 0.50 ml/min/kg. This is the first report, suggesting that serum clearance of iodixanol is a ready-to-use tool for a screening the GFR in monkeys, although it is necessary to perform a more longitudinal study using animals with reduced renal function.