[A longitudinal study of the association between physical activity and apathy among community-dwelling older adults].

AIM: This study clarified the association between the amount of physical activity and apathy after one year among community-dwelling older adults. METHODS: Two hundred community-dwelling older adults (mean age: 74.3±5.0 years old, female: 52.5%) who participated in the 2018 and 2019 "Kasama Longevity Health Examination" were included. Apathy was assessed using the Apathy Scale (0-42 points; the higher the score, the lower the motivation), physical activity by Physical Activity Scale for the Elderly (PASE), and Geriatric Depression Scale-15 (GDS). The 2018 PASE data were grouped into tertiles. A multiple regression analysis was performed with the 2019 Apathy Scale as the dependent variable and the 2018 PASE as the independent variable, and the sex, age, years of education, economic situation, body mass index, chronic illness, smoking history, alcohol drinking habits, physical function, cognitive function, GDS, and the 2018 Apathy Scale as adjustment variables. The PASE subcategories (leisure-time, household, and work-related activities) were examined using a similar method. RESULTS: The mean Apathy Scale in 2019 was 14.0±6.2 for the low physical activity group, 12.8±6.0 for the medium physical activity group, and 10.1±5.9 for the high physical activity group. The high physical activity group showed a significant negative association with the Apathy Scale (B=-1.56, 95% confidence interval=-2.91 to -0.21, p=0.023). No association was found for any activity of the PASE sub-items. CONCLUSIONS: A high level of physical activity may protect against apathy among community-dwelling older adults.

Differentiation of submandibular sialadenitis based on apparent diffusion coefficient.

OBJECTIVES: This study aimed to quantify the submandibular gland in suppurative sialadenitis, primary Sjögren's syndrome (pSS) and radiation-induced sialadenitis using the apparent diffusion coefficient (ADC) for differential diagnosis. SUBJECTS AND METHODS: This retrospective study included 16 patients with suppurative sialadenitis (n = 9), pSS (n = 3) and radiation-induced sialadenitis (n = 4) who underwent magnetic resonance imaging between June 2006 and May 2022. The ADC of the submandibular glands in each state was calculated, and the differences were analysed using a one-way analysis of variance and Tukey's post hoc test. Receiver operating characteristic curves were used to assess the ability of the ADC to distinguish each condition. Statistical significance was set at p < 0.05. RESULTS: The mean ADC value (×10-3 mm2/s) ± standard deviation in the control (non-affected side of the suppurative sialadenitis group), suppurative sialadenitis, pSS and radiation-induced groups were 0.94 ± 0.16, 1.24 ± 0.16, 1.33 ± 0.13 and 1.5 ± 0.12, respectively (p < 0.001). The diagnostic value for distinguishing each group was ≥0.75. CONCLUSION: ADC values are useful for quantitatively assessing and distinguishing submandibular glands in suppurative sialadenitis, primary Sjögren's syndrome and radiation-induced sialadenitis.

Graphical user interface-based convolutional neural network models for detecting nasopalatine duct cysts using panoramic radiography.

Nasopalatine duct cysts are difficult to detect on panoramic radiographs due to obstructive shadows and are often overlooked. Therefore, sensitive detection using panoramic radiography is clinically important. This study aimed to create a trained model to detect nasopalatine duct cysts from panoramic radiographs in a graphical user interface-based environment. This study was conducted on panoramic radiographs and CT images of 115 patients with nasopalatine duct cysts. As controls, 230 age- and sex-matched patients without cysts were selected from the same database. The 345 pre-processed panoramic radiographs were divided into 216 training data sets, 54 validation data sets, and 75 test data sets. Deep learning was performed for 400 epochs using pretrained-LeNet and pretrained-VGG16 as the convolutional neural networks to classify the cysts. The deep learning system's accuracy, sensitivity, and specificity using LeNet and VGG16 were calculated. LeNet and VGG16 showed an accuracy rate of 85.3% and 88.0%, respectively. A simple deep learning method using a graphical user interface-based Windows machine was able to create a trained model to detect nasopalatine duct cysts from panoramic radiographs, and may be used to prevent such cysts being overlooked during imaging.

Visualising cervical lymph nodes in jaw osteonecrosis using diffusion-weighted imaging.

OBJECTIVES: This study aimed to apply diffusion-weighted imaging to the evaluation of cervical lymph nodes affected by medication-related osteonecrosis of the jaw (MRONJ). METHODS: This retrospective study analysed the diffusion-weighted imaging data of 70 patients with or without MRONJ (Stages 0-3). The mean apparent diffusion coefficient (ADC) values of the submandibular (level IB) and superior internal jugular (level IIA) nodes in the control and MRONJ groups were calculated, and differences were analysed using the Mann-Whitney test. Moreover, receiver operating characteristic (ROC) curve analysis was performed to evaluate the ability of ADC values to predict lymph nodes that were affected by MRONJ. p < 0.05 was considered statistically significant. RESULTS: The median [interquartile range] (×10-3 mm2/s) of level IB was 0.74 [0.7-0.81] and 0.93 [0.84-1.09] and that of level IIA was 0.79 [0.76-0.85] and 0.97 [0.84-1.06] in the control and MRONJ groups respectively. ROC analysis revealed that the ADC value had excellent ability to discriminate between the control and MRONJ groups. CONCLUSIONS: The study findings indicate that diffusion-weighted imaging can contribute to differentiation of MRONJ from other cervical lymph node diseases and facilitate early detection of MRONJ.

Association between comorbidities associated with diabetes and higher-level functional status in older patients with type 2 diabetes mellitus: a cross sectional study.

PURPOSE: To investigate the association between comorbidities associated with diabetes and higher-level functional status as well as the relationship between comorbidities associated with diabetes and higher-level functional status in older patients with type 2 diabetes mellitus who have better social networks. METHODS: Participants were outpatients with type 2 diabetes aged ≥ 65 years, excluding individuals with severe cardiovascular or respiratory illness, hyperglycaemic crisis, type 1 diabetes, or diabetic foot. The Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) was used to evaluate the higher-level functional status. A TMIG-IC score of ≤ 9, instrumental activities of daily living (IADL) ≤ 4, intellectual activity or social role ≤ 3 were defined as decline in higher-level functional status. The comorbidities investigated included peripheral neuropathy, retinopathy, nephropathy, cognitive impairment, depression, frailty, sarcopenia, low muscle strength, stroke, heart disease, and arthritis. RESULTS: The analysis included 198 patients (mean age 75.9 ± 5.7 years, male 60.1%). After adjusting for potential confounders, depression was associated with TMIG-IC (Prevalence ratio (PR) 2.34, 95% confidence interval (CI) 1.44-3.82), low muscle strength was associated with IADL (PR 2.85, 95% CI 1.30-6.27), and frailty was associated with intellectual activity (PR 1.38, 95% CI 1.10-1.74). In the model with social networks added as a confounder, the relationship between depression or low muscle strength and higher-level functional status was not statistically significant. CONCLUSION: Comorbidities of depression and low muscle strength for older patients with type 2 diabetes mellitus increase the risk of malfunctioning of higher-level functional status. Increased interactions with family, friends and neighbours may reduce this event.

The relationship between acceleration in sit-to-stand and falls in community-dwelling older adults: cross-sectional study.

[Purpose] This study aimed to determine the relationship between acceleration parameters in the sit-to-stand (STS) movement and falls, and the strength of the association between acceleration in STS movements and falls in older adults. [Participants and Methods] In total, 330 older adults were included. Four acceleration parameters were measured in STS movement: maximum acceleration (MA), velocity (MV), power (MP), and stand-up time (ST). For the conventional STS tests, 5 times STS test (5xSTS) and ground reaction force (maximal rate of force development per body weight: RFD/w, peak reaction force per body weight: F/w, chair-rise time: T) were measured. Poisson regression analysis adjusted for confounding factors was used. [Results] In the model adjusted for confounders, significant associations were observed among MV (Prevalence ratio (PR): 0.75; 95% confidence interval (CI): 0.58-0.98), MP (PR: 0.67; 95% Cl: 0.68-0.93), RFD/w (PR: 0.70; 95% Cl: 0.56-0.87), and T (PR: 1.14; 95% Cl: 1.05-1.24). [Conclusion] Among the acceleration parameters, MP was most strongly associated with falls and was considered the most useful parameter for evaluation. In addition, comparisons with the conventional chair rise tests suggested that MP was stronger than the 5xSTS test and may be equally related to the RFD/w.

Texture analysis using short-tau inversion recovery magnetic resonance images to differentiate squamous cell carcinoma of the gingiva from medication-related osteonecrosis of the jaw.

OBJECTIVES: Despite the difficulty in distinguishing between squamous cell carcinoma (SCC) and medication-related osteonecrosis of the jaw (MRONJ) on the basis of medical imaging examinations, the two conditions have completely different treatment methods and prognoses. Therefore, differentiation of SCC from MRONJ on imaging examinations is very important. This study aimed to distinguish SCC from MRONJ by performing texture analysis using magnetic resonance imaging (MRI) short-tau inversion recovery images. METHODS: This retrospective case-control study included 14 patients with SCC of the lower gingiva and 35 with MRONJ of the mandible who underwent MRI and computed tomography (CT) for suspected SCC or MRONJ. SCC was identified by histopathological examination of tissues excised during surgery. The radiomics features of SCC and MRONJ were analyzed using the open-access software MaZda version 3.3 (Technical University of Lodz, Institute of Electronics, Poland). CT was used to evaluate the presence or absence of qualitative findings (sclerosis, sequestrum, osteolysis, periosteal reaction, and cellulitis) of SCC and MRONJ. RESULTS: Among the 19 texture features selected using MaZda feature-reduction methods, SCC of the gingiva and MRONJ of the mandible revealed differences in two histogram features, one absolute gradient feature, and 16 Gy level co-occurrence matrix features. In particular, the percentile, angular second moment, entropy, and difference entropy exhibited excellent diagnostic performance. CONCLUSION: Non-contrast-enhanced MRI texture analysis revealed differences in texture parameters between mandibular SCC and mandibular MRONJ. MRI texture analysis can be a new noninvasive quantitative method for distinguishing between SCC and MRONJ.

Relationship between Acceleration in a Sit-To-Stand Movement and Physical Function in Older Adults.

Acceleration parameters in sit-to-stand (STS) movements are useful for measuring lower-limb function in older adults. The purpose of this study was to examine the relationship between acceleration in STS movements and physical function and the test-retest reliability of acceleration parameters in older adults. We performed cross-sectional analyses on 244 older adults including 107 men (mean age: 77.4 ± 4.7) and 137 women (mean age: 75.6 ± 5.3). Four acceleration parameters were measured in STS movements: maximum acceleration (MA), maximum velocity (MV), maximum power (MP), and stand-up time (ST). Good intraclass correlation coefficients (ICC > 0.70) were observed for all parameters. For the acceleration parameters, MA, MV, and MP were relatively strongly associated with the 5-time STS test (men: r = -0.36~-0.47; women: r = -0.37~-0.45) and the timed up and go test (men: r = -0.39~0.47, women: r = -0.43~-0.51): MP was also strongly associated with grip strength (men: r = 0.48, women: r = 0.43). All acceleration parameters were poorer in participants reporting mobility limitations than in those reporting no mobility limitations. These findings support the usefulness of sensor-based STS measurement. The system is expected to be useful in various settings where care prevention is addressed.

Central vascular malformations of the mandible: characteristic findings in computed tomography and magnetic resonance imaging.

Central vascular malformations (CVMs) of the mandible are rare and can have varied clinical and radiological characteristics, thus making differential diagnosis difficult. We retrospectively reviewed 5 patients with proven CVM who underwent computed tomography (CT) and magnetic resonance imaging (MRI), including diffusion-weighted imaging (DWI) (and magnetic resonance angiography (MRA) for one patient), to assess the characteristic imaging findings of this lesion. CT revealed multilocularity in 3 lesions. All CVMs produced fine, irregular borders and low-to-intermediate density. Lesion continuity with the mandibular canal was discovered in 4 cases and enlarged feeding and outflow vessels in 3 lesions. Bone overgrowth was observed in 2 patients. CT values ranged from 30.84 to 52.87 Hounsfield units (HU). MRI exhibited low to intermediate signals on T1-weighted imaging (T1WI), signals ranging from low to intermediate-to-high on T2WI, and low to high signal intensity on short-tau inversion recovery (STIR) images, with flow voids in all patients and no inflammation in surrounding tissues. As calculated with DWI, the apparent diffusion coefficient (ADC) ranged from 0.69 to 1.74 × 10-3 mm2/s. MRA showed the presence of feeding vessels in 1 lesion. Interexaminer agreement on image interpretation ranged from moderate to excellent. These typical CVM imaging findings may aid in the differential diagnosis of this lesion.

Differential diagnosis of parotid gland tumors using apparent diffusion coefficient, texture features, and their combination.

OBJECTIVES: Warthin's tumors (WT) and pleomorphic adenomas (PA) are the commonest parotid gland tumors; however, their differentiation remains difficult. This study aimed to investigate the utility of the apparent diffusion coefficient (ADC) value, texture features, and their combination for the differential diagnosis of parotid gland tumors. METHODS: Patients who underwent magnetic resonance imaging (MRI) between April 2008 and March 2021 for parotid gland tumors were included and divided into two groups according to the tumor type: WT and PA. The tumor types were used as predictor variables, while the ADC value, texture features, and their combination were the outcome variables. Texture features were measured on short tau inversion recovery (STIR) images and selected using the Fisher's coefficient method and probability of error, and average correlation coefficients. The Mann-Whitney U-test was used to analyze bivariate statistics. Receiver operating characteristic curve analysis was used to assess the ability of the ADC value, texture features, and their combination to distinguishing between the two tumor types. RESULTS: A total of 22 patients were included, 11 in each group. The ADC value, 10 texture features, and their combination were significantly different between the two groups (p < .001). Moreover, all three variables had high area under the curve values of 0.93-0.96. CONCLUSION: The ADC value, texture features, and their combination demonstrated good diagnostic ability to distinguish between WTs and PAs. This method may be used to aid the differential diagnosis of parotid gland tumors, thereby promoting timely and adequate treatment.

Diagnostic efficacy of apparent diffusion coefficient, texture features, and their combination for differential diagnosis of odontogenic cysts and tumors.

OBJECTIVE: This study assessed the diagnostic efficacy of apparent diffusion coefficient (ADC), texture features, and their combination for the differential diagnosis of odontogenic cysts and tumors with cyst-like features. STUDY DESIGN: In total, 14 dentigerous cysts (DCs), 12 odontogenic keratocysts (OKCs), and 6 unicystic ameloblastomas (UABs) were used as predictor variables in 32 outpatients who underwent magnetic resonance imaging. The outcome variables were ADC, texture features, and their combination for each lesion. Texture features including histogram and gray-level co-occurrence matrix (GLCM) were measured on ADC maps. Ten features were selected by using the Fisher coefficient method. The Kruskal-Wallis test and post hoc Mann-Whitney test with Bonferroni adjustment were used to analyze trivariate statistics. Statistical significance was established at P < .05. Receiver operating characteristic analysis was used to evaluate the diagnostic effect of ADC, texture features, and their combination in distinguishing the lesions from each other. RESULTS: Apparent diffusion coefficient, 1 histogram feature, 9 GLCM features, and their combination demonstrated significant differences between DC, OKC, and UAB (P ≤ .01). Receiver operating characteristic analysis revealed a high area under the curve of .95 to 1.00 for ADC, 10 texture features, and their combination. Sensitivity, specificity, and accuracy ranged from .86 to 1.00. CONCLUSIONS: Apparent diffusion coefficient and texture features, alone or in combination, can be clinically important in facilitating the distinction between these odontogenic lesions.

Quantitative analysis of masticatory muscle changes by Eichner index using diffusion-weighted imaging.

OBJECTIVES: Diffusion-weighted imaging (DWI) provides quantitative functional information about the microscopic movement of water at the cellular level. However, few reports have quantitatively evaluated histological changes in masticatory muscles due to changes in occlusal relationships using DWI. This study aimed to assess the changes in masticatory muscles by Eichner index using DWI. METHODS: We analyzed magnetic resonance imaging (MRI) studies of 201 patients from November 2017 to April 2018. Each Eichner index group, age, and sex were used as criterion variables, and the average apparent diffusion coefficient (ADC) values of the masticatory muscles were the explanatory variable. The mean ADC value differences were analyzed in each Eichner index group. We analyzed the data using the Kruskal-Wallis test and post hoc Mann-Whitney test with Bonferroni adjustment multiple regression analysis with Shapiro-Wilk test and Spearman's correlation coefficients. P < 0.05 was considered statistically significant. RESULTS: The mean ADC values of each Eichner classification group were significantly different, with the lowest value in group C (P < 0.001). There was a negative correlation between the ADC value of the masseter, lateral pterygoid muscle, and age (P < 0.001). There were significant differences between the sex groups (P < 0.001). CONCLUSIONS: ADC values of masticatory muscles were significantly different in the Eichner index groups. The ADC values of masticatory muscles may be useful for the quantitative evaluation of the masticatory muscles affected by the occlusal state.

[Changes in the physical fitness of elderly people in the COVID-19 pandemic: An examination using performance tests].

OBJECTIVE: This study aimed to ascertain the physical-fitness trends among community-dwelling older adults using performance testing. The results of the evaluation conducted during the COVID-19 pandemic were compared to data from the pre-pandemic period. METHODS: A total of 240 community-dwelling older adults who participated in a health checkup program from 2016-2020 underwent the following tests: grip strength (upper limb muscle), single-leg balance with eyes open (static balance), sit-and-reach test (flexibility), timed up-and-go test (TUG, functional mobility), 5 meter habitual walk (walking ability), and hand working with pegboard (hand dexterity). Linear mixed effect models were applied to the hierarchical dataset: repeated data (Level 1), pre-pandemic (2016-2019), pandemic (2019-2020) (Level 2), and individuals (Level 3). Fixed effects and interactions were estimated for the survey year (Level 1), and between the survey year and pre- and post-pandemic (Level 2), with the range of decline set measured in terms of its standardized partial regression coefficient, "B," from 2019-2020. RESULTS: The items for which significant cross-level interactions were identified. In males, the following items showed significant cross-level interactions: sit and reach test (B=-2.56, 95% CI: -4.45--0.66 cm), TUG (+0.39, 0.21-0.56 sec) and 5 meter habitual walk (+0.15, 0.04-0.27 sec). In females items except single-leg balance with eyes open showed significant cross-level interactions: grip strength (-0.58, -1.11--0.05 kg), sit-and-reach test (-3.53, -5.11--1.95 cm), TUG (+0.15, 0.03-0.27 sec), for 5 meter habitual walk (+0.14, 0.04-0.24 sec), and hand working with pegboard (+0.89, 0.28-1.51 sec). CONCLUSION: In both males and females, a significant deterioration in flexibility and mobility movement ability was observed in 2019-2020. In addition, upper limb muscle strength and hand dexterity movement deteriorated in females.

Texture analysis of low-flow vascular malformations in the oral and maxillofacial region: venous malformation vs. lymphatic malformation.

Purpose: It is challenging for radiologists to distinguish between venous malformations (VMs) and lymphatic malformations (LMs) using magnetic resonance imaging (MRI). Thus, this study aimed to differentiate VMs from LMs using non-contrast-enhanced MRI texture analysis. Material and methods: This retrospective case-control study included 12 LM patients (6 men and 6 women; mean age 43.58, range 7-85 years) and 29 VM patients (7 men and 22 women; mean age 53.10, range 19-76 years) who underwent MRI for suspected vascular malformations. LM and VM patients were identified by histopathological examination of tissues excised during surgery. The texture features of VM and LM were analysed using the open-access software MaZda version 3.3. Seventeen texture features were selected using the Fisher and probability of error and average correlation coefficient methods in MaZda from 279 original parameters calculated for VM and LM. Results: Among 17 selected texture features, the patients with LM and VM revealed significant differences in 1 histogram feature, 8 grey-level co-occurrence matrix (GLCM) features, and 1 grey-level run-length matrix feature. At the cut-off values of the histogram feature [skewness ≤ -0.131], and the GLCM features [S(0, 2) correlation ≥ 0.667, S(0, 3) correlation ≥ 0.451, S(0, 4) correlation ≥ 0.276, S(0, 5) correlation ≥ 0.389, S(1, 1) correlation ≥ 0.739, S(2, 2) correlation ≥ 0.446, S(2, -2) correlation ≥ 0.299, S(3, -3) correlation ≥ 0.091] had area under the curves of 0.724, 0.764, 0.773, 0.747, 0.733, 0.759, 0.730, 0.744 and 0.727, respectively. Conclusions: Non-contrast-enhanced MRI texture analysis allows us to differentiate between LMs and VMs.

Quantitative assessment of the parotid gland using computed tomography texture analysis to detect parotid sialadenitis.

OBJECTIVE: We aimed to quantitatively assess the parotid gland by using computed tomography (CT) texture analysis to detect parotid sialadenitis (PS). STUDY DESIGN: This retrospective case-control study included 43 patients with PS who underwent CT and magnetic resonance imaging (MRI). Parotid glands with an abnormal signal (STIR: High) on MRI were identified as showing PS. Patients with parotid gland tumors, bilateral PS, marked fatty degeneration, and severe artifacts on CT were excluded. The texture features of parotid glands with PS and the contralateral normal parotid glands were analyzed using the open-access software LIFEx. The regions of interest were manually placed by tracing contours of both parotid glands on CT images. The results were tested with the paired t-test (or Wilcoxon rank-sum test when appropriate). Receiver operating characteristic (ROC) curve analysis was performed to assess the ability of texture features to predict PS. RESULTS: Six gray level run length matrix features, 2 neighborhood gray level difference matrix features, and 5 gray level zone length matrix features displayed significant differences between PS and normal glands (P ≤ .047). ROC curve analysis showed acceptable accuracy in 4 texture features. CONCLUSIONS: CT texture analysis allowed quantitative assessment of parotid glands and may have the potential to detect PS.

Quantitative Assessment of the Mandibular Condyle in Patients With Rheumatoid Arthritis Using Diffusion-Weighted Imaging.

PURPOSE: The purpose of this study was to quantitatively assess the mandibular condyle in patients with rheumatoid arthritis (RA) using the apparent diffusion coefficient (ADC) on diffusion-weighted imaging (DWI). PATIENTS AND METHODS: Thirty-one patients with RA and temporomandibular joint (TMJ) pain who underwent magnetic resonance imaging (MRI) examination of the TMJs at our hospital between August 2006 and March 2020 were included in this study. Twenty-one patients with normal TMJs who underwent MRI examination at our hospital between August 2006 and March 2020 were included as controls. The MRI findings were compared between the 2 groups. RESULTS: The mean ADC values of the mandibular condyle in patients with RA were 1.20 ± 0.17 × 10-3 mm2/second. The mean ADC values of the mandibular condyle in patients with RA were significantly greater than the controls (P < .01). Receiver operating characteristic curve analysis revealed a cutoff of 0.89 for the ADC values of the mandibular condyle in patients with RA. The receiver operating characteristic curve analysis revealed areas under the curve for maximum ADC values of 0.98. CONCLUSIONS: Our study found that the ADC on DWI could be used for the quantitative assessment of the mandibular condyle in patients with RA, which indicated that the ADC on DWI could be useful for predicting RA.

Histological and mechanical comparisons of arytenoid cartilage between 4 brachycephalic and 8 non-brachycephalic dogs: A pilot study.

Brachycephalic airway syndrome (BAS) is a well-established cause of respiratory distress in dogs. BAS without surgical correction results in eventual laryngeal collapse. Arytenoid lateralization has been used to treat severe laryngeal collapse with some highly variable results. Chondromalacia and decreased stiffness of the arytenoid cartilage has been postulated a source of failure after arytenoid lateralization but no report of the histological characteristics and mechanical strength of arytenoid cartilage in brachycephalic dogs has been reported. Here we report histological and mechanical features in arytenoid cartilage of brachycephalic dogs. We identified the arytenoid cartilage in brachycephalic dogs presented degenerative histological characteristics and decreased load to failure and stiffness compared to that in non-brachycephalic dogs. Together, these observations suggest that degenerative condition of arytenoid cartilage in brachycephalic dogs could contribute to chondromalacia and mechanical weakness of arytenoid cartilage and result in cause of failure after arytenoid lateralization.

Osteochondral regeneration using scaffold-free constructs of adipose tissue-derived mesenchymal stem cells made by a bio three-dimensional printer with a needle-array in rabbits.

Osteoarthritis is a major joint disease for which medical interventions have been extensively investigated in humans and animals. In this study, we examined the regeneration of articular cartilage and subchondral bone using a scaffold-free construct consisting of adipose tissue-derived mesenchymal stem cells (AT-MSCs) fabricated using a bio three-dimensional (3D) printer. AT-MSCs were isolated from three rabbits and cultured to a number of sufficient for creation of 3D-printed constructs. One construct consisted of 960 spheroids obtained from 3.5 × 104 autologous AT-MSCs. The construct was then implanted into an osteochondral defect (diameter 4 mm and depth 4 mm) surgically bored into the left femoral trochlear groove of each rabbit. Three months after implantation, healing was assessed by computed tomography, magnetic resonance (MR) imaging, and pathology. MR images were evaluated based on a modified two-dimensional (2D)-magnetic resonance observation of cartilage repair tissue (MOCART) grading system, and gross and microscopic histology were scored according to the International Cartilage Repair Society scale. At the time of imaging, treated defects had become radiopaque, while control defects remained radiolucent. Total 2D-MOCART scores were higher in the implanted defects than in the controls, but not to a statistically significant extent. Similarly, average histological scores were comparable among all groups, although average gross scores were significantly higher in implanted defects than in controls. This is the first demonstration of a scaffold-free 3D-printed construct consisting of autologous AT-MSCs regenerating cartilage and subchondral bone within three months.

Characteristics and multipotency of equine dedifferentiated fat cells.

Dedifferentiated fat (DFAT) cells have been shown to be multipotent, similar to mesenchymal stem cells (MSCs). In this study, we aimed to establish and characterize equine DFAT cells. Equine adipocytes were ceiling cultured, and then dedifferentiated into DFAT cells by the seventh day of culture. The number of DFAT cells was increased to over 10 million by the fourth passage. Flow cytometry of DFAT cells showed that the cells were strongly positive for CD44, CD90, and major histocompatibility complex (MHC) class I; moderately positive for CD11a/18, CD105, and MHC class II; and negative for CD34 and CD45. Moreover, DFAT cells were positive for the expression of sex determining region Y-box 2 as a marker of multipotency. Finally, we found that DFAT cells could differentiate into osteogenic, chondrogenic, and adipogenic lineages under specific nutrient conditions. Thus, DFAT cells could have clinical applications in tissue regeneration, similar to MSCs derived from adipose tissue.

Change in intrarenal Ghrelin expression in immune complex-mediated glomerular disease in dogs.

Ghrelin is a peptide hormone that is mainly produced by the stomach. The kidney is a major source of local ghrelin, and maintaining body fluid balance is considered a critical role of renal ghrelin. However, there are no reports on renal ghrelin in small animal medicine. The present study investigated the intrarenal localization of and change in ghrelin expression in dogs with immune complex-mediated glomerulonephritis (ICGN). Ghrelin immunoreactivity (IR) was observed in the distal tubules of normal kidneys. Ghrelin IR was weak in ICGN kidneys, and the quantitative ghrelin IR score was significantly lower in ICGN kidneys than in normal kidneys. In cases of ICGN, plasma creatinine concentrations showed a positive correlation with the ghrelin IR score.