In Vivo Study for Clinical Application of Dental Stem Cell Therapy Incorporated with Dental Titanium Implants.

The aim of this study was to investigate the behavior of dental-derived human mesenchymal stem cells (d-hMSCs) in response to differently surface-treated implants and to evaluate the effect of d-hMSCs on local osteogenesis around an implant in vivo. d-hMSCs derived from alveolar bone were established and cultured on machined, sandblasted and acid-etched (SLA)-treated titanium discs with and without osteogenic induction medium. Their morphological and osteogenic potential was assessed by scanning electron microscopy (SEM) and real-time polymerase chain reaction (RT-PCR) via mixing of 5 × 106 of d-hMSCs with 1 mL of Metrigel and 20 µL of gel-cell mixture, which was dispensed into the defect followed by the placement of customized mini-implants (machined, SLA-treated implants) in New Zealand white rabbits. Following healing periods of 2 weeks and 12 weeks, the obtained samples in each group were analyzed radiographically, histomorphometrically and immunohistochemically. The quantitative change in osteogenic differentiation of d-hMSCs was identified according to the type of surface treatment. Radiographic analysis revealed that an increase in new bone formation was statistically significant in the d-hMSCs group. Histomorphometric analysis was in accordance with radiographic analysis, showing the significantly increased new bone formation in the d-hMSCs group regardless of time of sacrifice. Human nuclei A was identified near the area where d-hMSCs were implanted but the level of expression was found to be decreased as time passed. Within the limitations of the present study, in this animal model, the transplantation of d-hMSCs enhanced the new bone formation around an implant and the survival and function of the stem cells was experimentally proven up to 12 weeks post-sacrifice.

Clinical Anatomy of the Puboprostatic Ligament for the Safe Guidance for the Prostate Surgery.

OBJECTIVE: To provide the anatomy of the puboprostatic ligament and related structures to save urogenital competence after prostatectomy. MATERIALS AND METHODS: Pelvic areas of 31 adult cadavers were dissected to figure out the shape, number, and location of the puboprostatic ligaments. RESULTS: The puboprostatic ligament was the most important support structure between the pubic bone and prostate gland. Puboprostatic ligaments were bilaterally single (61.3%), bilaterally double (19.4%), or mixed (19.4%). Ligaments were mostly I-shaped (53.8%). If ligaments had extra attachment to or from the arcuate line, the ligaments were λ-shaped (36.3%), or Y-shaped (8.8%). In one case, the ligament had a central fusion with an irregular shape. I-shaped puboprostatic ligaments were observed more frequently in specimens with double ligaments, while λ-shaped puboprostatic ligaments were observed more frequently in the cases with single ligaments. The average distance between both puboprostatic ligaments was 8.1 mm at the pubic site and 14.2 mm at the prostate site. The distance was narrower when the specimen had double puboprostatic ligaments on both sides. The neurovascular bundle ran beneath the puboprostatic ligament. If the ligament was the λ-shaped type, the neurovascular bundle frequently pierced the lateral band of the ligament. CONCLUSION: Puboprostatic ligaments hold and stabilize the prostate against the pubic bone. It is believed that a pelvis with bilateral, double puboprostatic ligaments would have advantages in urogenital competence. The morphologic data of the shape, multiplicity, and location of the PPLs would help to make a plan to approach the prostate.

Synergistic effect of hyperbaric oxygen therapy with PTH [1-34] on calvarial bone graft in irradiated rat.

OBJECTIVE: To determine the synergistic effect of parathyroid hormone (PTH) [1-34] in combination with hyperbaric oxygen (HBO) on bone graft in a rat calvarial bone defect model under impaired osteogenic conditions. MATERIALS AND METHODS: Twenty-four rats were divided into three groups. Localized radiation with a single 12 Gy dose was administered to the calvaria. Four weeks after radiation, calvarial circular defects were created in the parietal bones. All defects were filled with biphasic calcium phosphate. After the bone graft, PTH [1-34] was injected subcutaneously, and HBO was administered. At 6 weeks after the bone graft, the rats were sacrificed, and specimens were harvested. RESULTS: Histomorphometric evaluation showed that the percentage of new bone area was higher in the PTH and PTH/HBO groups than in the control group. The percent residual material area was decreased in the PTH/HBO group compared with the control group. The percentage blood vessel number was highest in the PTH group. Micro-CT evaluation showed that the new bone volume was highest in the PTH/HBO group. The residual material volume was lowest in the PTH/HBO group. CONCLUSION: Within the limitations of this study, our data indicate that PTH combined with HBO may reverse radiation-induced impairment of bone healing.

Clinical Relevance of Poststent Fractional Flow Reserve After Drug-Eluting Stent Implantation.

BACKGROUND: The prognostic value of poststent fractional flow reserve (FFR) has not been clearly defined in patients with drug-eluting stent (DES) implantation. This study sought to evaluate the association between FFR and clinical outcomes after DES implantation with intravascular ultrasound (IVUS) assistance. METHODS: A total of 115 lesions (107 patients) with FFR measurement after IVUS-assisted DES implantation were enrolled. Poststent angiographic and IVUS parameters were compared with FFR values. Clinical outcomes were assessed by target vessel failure (TVF), defined as a composite of target vessel revascularization, death, or non-fatal myocardial infarction attributed to the target vessel. RESULTS: Mean poststent FFR was 0.92 ± 0.04. Minimal stent area by IVUS had a positive correlation with poststent FFR (r = 0.36; P<.01). Poststent FFR ≥0.89 was a physiologic cut-off value for 1-year TVF-free survival. The best cut-off value of minimal stent area to define poststent FFR ≥0.89 was >5.4 mm² (sensitivity, 63.2%; specificity, 90.0%). At 3-year follow-up, lesions with poststent FFR ≥0.89 had a better TVF-free survival rate than those with poststent FFR <0.89 (89.3% vs 61.1%, P =.03). CONCLUSION: Poststent FFR can be a useful predictor for long-term clinical outcomes after DES implantation and relevant to IVUS minimal stent area.

Concealed primary aortic sarcoma induced hypertensive encephalopathy resulting from a thoracic aortic occlusion: a case report.

Primary aortic sarcoma is a rare condition that is frequently associated with distal embolization. In addition, growth characteristics of primary aortic sarcoma lead to the narrowing of the involved aortic lumen. A 72-year-old Korean male with primary aortic sarcoma showed progressive unexplained blood pressure elevation that didn't improve with additional antihypertensive drug therapy. Because follow-up measures were not taken, the patient ultimately developed hypertensive encephalopathy with concurrent embolic dissemination. Although we successfully performed open transcatheter embolectomy in both legs, the patient died because of multiple organ failure 3 days after surgery. Given the ominous prognosis for this condition, this case report highlights the fact that the value of early detection and prompt evaluation of altered vital signs should not be overemphasized. We describe a rare case of primary aortic sarcoma that showed hypertensive encephalopathy caused by thoracic aortic occlusion and also had embolic metastases to the lower extremities.

Toxicity evaluation of complex metal mixtures using reduced metal concentrations: application to iron oxidation by Acidithiobacillus ferrooxidans.

In this study, we investigated the inhibition effects of single and mixed heavy metal ions (Zn2+, Ni2+, Cu2+, and Cd2+) on iron oxidation by Acidithiobacillus ferrooxidans. Effects of metals on the iron oxidation activity of A. ferrooxidans are categorized into four types of patterns according to its oxidation behavior. The results indicated that the inhibition effects of the metals on the iron oxidation activity were noncompetitive inhibitions. We proposed a reduced inhibition model, along with the reduced inhibition constant (alpha i), which was derived from the inhibition constant (KI) of individual metals and represented the tolerance of a given inhibitor relative to that of a reference inhibitor. This model was used to evaluate the toxicity effect (inhibition effect) of metals on the iron oxidation activity of A. ferrooxidans. The model revealed that the iron oxidation behavior of the metals, regardless of metal systems (single, binary, ternary, or quaternary), is closely matched to that of any reference inhibitor at the same reduced inhibition concentration, [I]reduced, which defines the ratio of the inhibitor concentration to the reduced inhibition constant. The model demonstrated that single metal systems and mixed metal systems with the same reduced inhibitor concentrations have similar toxic effects on microbial activity.