Dedifferentiated Fat (DFAT) cells: A cell source for oral and maxillofacial tissue engineering

Tissue engineering is a promising method for the regeneration of oral and maxillofacial tissues. Proper selection of a cell source is important for the desired application. This review describes the discovery and usefulness of dedifferentiated fat (DFAT) cells as a cell source for tissue engineering. Dedifferentiated Fat cells are a highly homogeneous cell population (high purity), highly proliferative, and possess a multilineage potential for differentiation into various cell types under proper in vitro inducing conditions and in vivo. Moreover, DFAT cells have a higher differentiation capability of becoming osteoblasts, chondrocytes, and adipocytes than do bone marrow-derived mesenchymal stem cells and/or adipose tissue-derived stem cells. The usefulness of DFAT cells in vivo for periodontal tissue, bone, peripheral nerve, muscle, cartilage, and fat tissue regeneration was reported. Dedifferentiated Fat cells obtained from the human buccal fat pad (BFP) are a minimally invasive procedure with limited esthetic complications for patients. The BFP is a convenient and accessible anatomical site to harvest DFAT cells for dentists and oral surgeons, and thus is a promising cell source for oral and maxillofacial tissue engineering.

Abstract P3-01-09: Re-evaluating the “10% rule” for sentinel lymph node biopsy with radioactive method in breast cancer; a single institutional retrospective study

Background:

When multiple radioactive sentinel lymph nodes (SLNs) are present during sentinel lymph node biopsy (SLNB), excision of those SLNs with >10% radioactive count per minute (high-CPM) of the most radioactive node (“10% rule”) has been proposed. Although this “10% rule” may avoid excessive removal of SLNs,the risk of false negative and remnant positive SLNs in the patients who have SLNs with <10% CPM (low-CPM) remain unclear. The purpose of this analysis is to determine the clinical validity of this “10% rule” for early breast cancer patients.

Method:

We reviewed the records of successful SLNBs using the radioisotope (RI) method performed between January 2001 and December 2016 in our institution. The radioactive count from each excised SLN was measured. Non-radioactive lymph nodes were excluded from this analysis. All SLNs were pathologically assessed by 2mm serial section with hematoxylin and eosin staining.

Results:

In the 3,043 patients with successful SLNB,the median number of radioactive SLNs removed was 2 (mean, 1.8; range, 1-10) and 599 patients (19.7%) had SLNs with low-CPM. The total number of radioactive SLNs was 5,472, and 875 (16.0%) out of 5,472 SLNs were low-CPM. Sixty-one (7.0%) out of these 875 SLNs with low CPM in 56 patients (1.8%) had metastatic disease by pathological assessment. The number of metastatic SLN with low-CPM was one in 51 patients and two in 5 patients. Nineteen patients (0.6%) had no metastatic lesion in SLNs with high-CPM.

Discussion and Conclusions:

If SLNB was performed by RI method alone with “10% rule”, false negative rate increased by 0.6% and underestimation increased up to 1.8%. Furthermore, 19.7% of the patients have the benefit of avoiding excessive removal of SLNs.Considering the risk and benefit, “10% rule” is a high validitymethod to capture metastatic SLNs even in the setting that ALND will not be performed.

Citation Format: Miyamoto H, Aruga T, Onishi M, Goto R, Iwamoto N, Idera N, Horiguchi K, Honda Y. Re-evaluating the “10% rule” for sentinel lymph node biopsy with radioactive method in breast cancer; a single institutional retrospective study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-01-09.

Full-layer mucosal histology in achalasia: Histological epithelial wave is characteristic in "pinstripe pattern"-positive achalasia

BACKGROUND

Previously, the mucosal histology in achalasia has only been investigated using superficial biopsy or surgically resected esophageal specimens in end-stage cases. We investigated the histology of the full-layer mucosa in early and advanced achalasia.

METHODS

Endoscopy was performed for the pinstripe pattern (PSP) (an early achalasia indicator) and dilation and thickening of the mucosa (advanced achalasia indicators). A mucosal entry site for peroral endoscopic myotomy was created using cap-fitted endoscopic mucosal resection to access the full-layer mucosa and the submucosa.

KEY RESULTS

Mucosal histology was compared between 32 patients with achalasia and 15 controls. Histological esophagitis with findings of inflammatory cell infiltration and dilated intercellular spaces was observed more in patients with achalasia than in controls (87.5% vs 13.3%, P<.001; 84.4% vs 46.7%, P=.049). Muscularis mucosae (MM) atrophy and epithelial wave were only observed in achalasia (40.6% vs 0%, P=.005; 28.1% vs 0%, P=.043). Fibrosis was more common in achalasia, but without statistical significance (31.3% vs 20.0%, P=.503). In achalasia with endoscopic dilation and thickening of the mucosa, MM atrophy was observed histologically, and in cases involving endoscopic PSP, the histological epithelial wave was observed.

CONCLUSIONS & INFERENCES

Histological findings of esophagitis were observed endoscopically even in early achalasia. Pinstripe pattern corresponds to the epithelial wave observed histologically in achalasia, whereas endoscopic findings in advanced achalasia correspond to MM atrophy. Appropriate management is necessary during early achalasia to prevent progression to advanced achalasia with more severe histological changes.

The influence of aging on the effectiveness of heat stress in preventing disuse muscle atrophy

This study examined the aging effect on disuse muscle atrophy prevention using heat stress. Wistar rats aged 7 and 60 weeks were divided into three groups as follows: control, immobilized (Im), and immobilized and heat stressed (ImH). Heat stress was given by immersing the hindlimbs in hot water (42 °C) for 60 min, once in every 3 days and the gastrocnemius (GAS) and soleus (SOL) muscles were extracted after 14 days. Muscle-fiber types were classified using ATPase staining. Heat shock protein 70 (HSP70) was assessed through Western blotting. In GAS muscle of both groups and SOL muscle of 7-week-old rats, the fiber diameter of each muscle type in the ImH group significantly increased compared with that in the Im group. However, this could not be observed in the SOL muscle of the 60-week-old rats. The increased percentage of type-I fibers and variability of types I and II muscle-fiber diameter were evident in the SOL muscle of the 60-week rats. HSP70 was significantly elevated in the ImH group compared with in the Im group in both muscle types of both age groups. Thus, effectiveness of heat stress in the prevention of disuse muscle atrophy appears unsatisfactory in aging muscle fibers.

Changes in esophageal motility after endoscopic submucosal dissection for superficial esophageal cancer: a high-resolution manometry study

The effect of endoscopic submucosal dissection (ESD) on esophageal motility remains unknown. Therefore, the aim of this study is to elucidate changes in esophageal motility after ESD along with the cause of dysphagia using high-resolution manometry (HRM). This is a before-and-after trial of the effect of ESD on the esophageal motility. Twenty patients who underwent ESD for superficial esophageal carcinoma were enrolled in this study. Patients filled out a questionnaire about dysphagia and underwent HRM before and after ESD. Results before and after ESD were compared. Data were obtained from 19 patients. The number of patients who complained of dysphagia before and after ESD was 1/19 (5.3%) and 6/19 (31.6%), respectively (P = 0.131). Scores from the five-point Likert scale before and after ESD were 0.1 ± 0.5 and 1.0 ± 1.6, respectively (P = 0.043). The distal contractile integral (DCI) before and after ESD and the number of failed, weak, or fragmented contractions were not significantly different. However, in five patients with circumferential ESD, DCI was remarkably decreased and the frequency of fail, weak, or fragmented contractions increased. Univariate regression analysis showed a relatively strong inverse correlation of ΔDCI with the circumferential mucosal defect ratio {P < 0.01, standardized regression coefficient (r) = -0.65}, the number of stricture preventions (P < 0.01, r = -0.601), and the number of stricture resolutions (P < 0.01, r = -0.77). This HRM study showed that impairment of esophageal motility could be caused by ESD. The impairment of esophageal motility was conspicuous, especially in patients with circumferential ESD and subsequent procedures such as endoscopic triamcinolone injection and endoscopic balloon dilatation. Impaired esophageal motility after ESD might explain dysphagia.

Angiotensin-Converting Enzyme Inhibition Early After Heart Transplantation

BACKGROUND

Cardiac allograft vasculopathy (CAV) remains a leading cause of mortality after heart transplantation (HT). Angiotensin-converting enzyme inhibitors (ACEIs) may retard the development of CAV but have not been well studied after HT.

OBJECTIVES

This study tested the safety and efficacy of the ACEI ramipril on the development of CAV early after HT.

METHODS

In this prospective, multicenter, randomized, double-blind, placebo-controlled trial, 96 HT recipients were randomized to undergo ramipril or placebo therapy. They underwent coronary angiography, endothelial function testing; measurements of fractional flow reserve (FFR) and coronary flow reserve (CFR) and the index of microcirculatory resistance (IMR); and intravascular ultrasonography (IVUS) of the left anterior descending coronary artery, within 8 weeks of HT. At 1 year, the invasive assessment was repeated. Circulating endothelial progenitor cells (EPCs) were quantified at baseline and 1 year.

RESULTS

Plaque volumes at 1 year were similar between the ramipril and placebo groups (162.1 ± 70.5 mm³ vs. 177.3 ± 94.3 mm³, respectively; p = 0.73). Patients receiving ramipril had improvement in microvascular function as shown by a significant decrease in IMR (21.4 ± 14.7 to 14.4 ± 6.3; p = 0.001) and increase in CFR (3.8 ± 1.7 to 4.8 ± 1.5; p = 0.017), from baseline to 1 year. This did not occur with IMR (17.4 ± 8.4 to 21.5 ± 20.0; p = 0.72) or CFR (4.1 ± 1.8 to 4.1 ± 2.2; p = 0.60) in the placebo-treated patients. EPCs decreased significantly at 1 year in the placebo group but not in the ramipril group.

CONCLUSIONS

Ramipril does not slow development of epicardial plaque volume but does stabilize levels of endothelial progenitor cells and improve microvascular function, which have been associated with improved long-term survival after HT. (Angiotensin Converting Enzyme [ACE] Inhibition and Cardiac Allograft Vasculopathy; NCT01078363).

Relationship between sudden natural death and abdominal fat evaluated on postmortem CT scans

Objective

This study examined the association between sudden natural death and abdominal fat using postmortem computed tomography (CT) scans.

Subjects and methods

Postmortem CT images at the umbilical level of 241 subjects were used to measure abdominal areas of subcutaneous‐ and visceral fat, the rate of visceral fat and the waist circumference. Of the study subjects, 174 died of sudden natural death (130 men and 44 women), and 67 died of different causes (46 men and 21 women). All were between 40 and 75 years of age. Logistic regression analysis was performed to identify independent abdominal parameters associated with sudden natural death.

Results

By univariate analysis, the areas of subcutaneous and visceral fat were significantly larger in sudden natural death than who died of different causes (subcutaneous fat, odds ratio [OR] = 1.004, 95% confidence interval [CI] = 1.000–1.007, p = 0.03; visceral fat, OR = 1.008, 95% CI = 1.003–1.013, p < 0.01). Multivariate analysis showed that the area of visceral fat was an independent factor associated with the risk of sudden natural death (OR = 1.008, 95% CI = 1.002–1.015, p = 0.02).

Conclusions

Postmortem CT revealed that sudden natural death was related to abdominal fat deposits.

Impact of attenuated-signal plaque observed by intravascular ultrasound on vessel response after drug-eluting stent implantation

BACKGROUND AND AIMS

The aim of this study was to investigate the impact of attenuated-signal plaque (ASP) observed by intravascular ultrasound (IVUS) on vessel response after drug-eluting stent implantation.

METHODS

Data were derived from the IVUS cohort of the J-DESsERT trial comparing paclitaxel- and sirolimus-eluting stents. Serial IVUS analysis (pre- and post-intervention, and 8-month follow-up) was performed in 136 non-AMI lesions. ASP was defined as hypoechoic plaque with ultrasound attenuation without calcification. Calcified plaque (CP) was defined as brightly echoreflective plaque with acoustic shadowing. ASP and CP scores were calculated by grading their measured angle as 0 to 4 for 0°, <90°, 90-180°, 180-270° and >270°, respectively. The entire stented segment was analyzed at 1-mm intervals.

RESULTS

At pre-intervention, ASP was observed in 40.4% of lesions, and this group had greater % neointimal volume (%NIV) at follow-up than the no-ASP group (p = 0.011). ASP score at pre-intervention positively correlated with %NIV (p = 0.023). During the follow-up, ASP score significantly decreased (p < 0.001), and CP score significantly increased (p < 0.001), with a negative correlation between them (p < 0.001). A decrease in the ASP score was associated with less %NIV in PES (p = 0.031), but not in SES (p = 0.229).

CONCLUSIONS

The greater extent of plaque with IVUS-signal attenuation at pre-intervention and its persistence during follow-up were associated with neointimal proliferation, possibly representing sustained inflammatory status, depending on the type of DES used.

Impact of analysis interval size on the quality of optical frequency domain imaging assessments of stent implantation for lesions of the superficial femoral artery

OBJECTIVES

This study aimed to investigate the influence of analysis interval size on optical frequency domain imaging (OFDI) assessment of stent therapy for lesions of the superficial femoral artery (SFA).

BACKGROUND

No consensus or validating data are available with respect to the methodology of intravascular imaging analysis for the peripheral arteries.

METHODS

OFDI was performed for 30 SFA lesions, during endovascular therapy and at the 6-month follow-up. Initially, lumen and stent borders were traced at 1-mm axial intervals. Volumes were calculated using a PC-based software, and the volume index (VI) was defined as the volume divided by the stent length. Two additional OFDI analyses were performed using 2-mm and 5-mm intervals, thereby reducing the number of cross-sectional image frames analyzed.

RESULTS

The mean stent length was 89.7 ± 35.2 mm. The mean difference in baseline minimum lumen area (MLA) was 0.4 mm² between MLA values from the 1-mm and 2-mm interval analyses, and 2.2 mm² between MLA values from the 1-mm and 5-mm interval analyses. In volumetric analysis, there were excellent correlations and good agreements for stent, lumen, and neointimal VI measurements obtained on the basis of different analysis intervals.

CONCLUSIONS

Using large intervals in OFDI analyses of SFA lesions resulted in few differences in measurement variability of volumetric parameters. However, planar analysis for MLA assessment can be susceptible to high variability when large intervals are applied. © 2016 Wiley Periodicals, Inc.