Effect of F68, F127, and P85 Pluronic Block Copolymers on Odontogenic Differentiation of Human Tooth Germ Stem Cells

Introduction

The major challenge in dental pulp engineering is to make a successful combination of stem cells and biomaterials with the aim of providing the differentiation of stem cells into odontogenic cell types. Among biomaterials, some types of pluronics have been reported to increase bone formation of stem cells. The effect of these pluronics on odontogenic differentiation has not been addressed yet. This study aimed to examine the effect of pluronics F68, F127, and P85 on odontogenic differentiation of stem cells derived from third molar tooth germs of young adults.

Methods

Human tooth germ stem cells (hTGSCs) were induced to differentiate into odontogenic cells in the presence of different concentrations of pluronics. Differentiation efficiency was assessed by quantitative real-time polymerase chain reaction for determining expression messenger RNA levels and by immunocytostaining for determining the protein expression of odontogenic markers (ie, dentin sialoprotein, dentin matrix protein 1, bone morphogenic protein 2, bone morphogenic protein 7) by measuring alkaline phosphatase enzyme activity and lastly by von Kossa staining for determining mineralization.

Results

The results revealed for the first time that F68 has a great potential to boost odontogenic differentiation of hTGSCs. P85 was found to reduce cell viability during differentiation. F127 was nontoxic to hTGSCs but did not have any effect on differentiation.

Conclusions

The positive effect of F68 on odontogenic differentiation might enable more efficient pulp regeneration. Yet, the exact mechanism of how F68 alters the differentiation pattern of hTGSCs remains to be investigated in the future studies.     

Rapid pleurodesis in symptomatic malignant pleural effusion.

OBJECTIVE: The objective of the study was to see whether a rapid method of pleurodesis was superior to the standard protocol in patients with symptomatic malignant pleural effusion. METHODS: Between January 2000 and February 2003, a prospective randomised trial was carried out in a sequential sample of 27 patients with malignant pleural effusions documented cytopathologically. Twelve patients were allocated to group 1 (standard protocol) and 15 to group 2 (new protocol). A small-bore catheter (12 Fr) and oxytetracycline (35 mg/kg of body weight) were used in both groups. In group 1, patients had drainage until radiological evidence of lung re-expansion was obtained and the amount of fluid drained was less than 150 ml/day, before oxytetracycline was instilled. The catheter was removed when the amount of fluid drained after instillation was less than 150 ml/day. In group 2, patients had the oxytetracycline instilled in a fractionated-dose manner following frequent aspirations at 6h intervals. The catheter was removed when the total amount of fluid drained after instillation of the oxytetracycline [OT] was less than 150 ml/last three aspirations. Response was evaluated at 1, 3 and 6 months after pleurodesis. RESULTS: There was no statistically significant difference in the demographic features, site of the primary tumour, disease characteristics, and response rates in any evaluation period in both groups (P>0.05). However, the number of days of drainage and hospitalisation, and the cost were significantly lower in the second group (P<0.001). CONCLUSIONS: This new pleurodesis method provided shorter hospital stay resulting in superior cost-effectiveness and palliation without sacrificing the efficacy of pleurodesis.     

Blunt thoracic trauma in children: review of 137 cases.

OBJECTIVE: Thoracic injuries are uncommon in children and few report present on blunt ones. METHODS: Between 1994 and 2003, 137 children with blunt thoracic injury were reviewed. RESULTS: The mean age of children was 6.9+/-7.3 (1-16) years. Etiology was falls in 46.7%, traffical accidents in 51% and abuse in 2.2%. Average height in fallen-down cases was 6.4+/-2 (range: 3-11) m. Calculated mean kinetic energy transfer to body was 1923+/-1056 J. When first seen, 70% (82/117) of the patients had vital signs that were within normal limits. Forty-two (35.9%) children had isolated thoracic injury. Associated injuries were present in 75 (64.1%) children. Head injury was the most common associated injury present in 33 (28.2%). Pulmonary contusion was the most common thoracic injury with 68 (49.6%). Seventeen (12.4%) required surgery, 11 (8%) of them were thoracic (4 for diaphragmatic tear, 2 for flail chest, 2 for tracheobronchial injuries, 2 for laceration, 1 for esophageal rupture). Surgical group had higher ISS (26.8 vs 36.2, P = 0.001). Fifteen were lost (10.9%): There were lethal injuries in 7; chest tube treatment in 3; intensive care unit management in 2; mechanical support in 2 and observation in 1 patient. No death occurred for operations. Mortality rate was the lowest at injuries to chest alone and the highest for multi-system injuries (P < 0.05). The hospital length of stay for averaged 13.4+/-8.8 (range: 4-49) days. CONCLUSION: Associated injury is the most important mortality factor. Thoracic operations can be performed with minimal morbidity and without mortality in children with blunt thoracic trauma.     

Ptosis caused by pachydermoperiostosis

A 39-year-old man with pachydermoperiostosis is presented. He had enlarged, thickened upper eyelids that made it difficult for him to open his eyes. Eyelid correction was performed by resecting the excessive skin and orbicularis muscle in a fusiform shape and shortening the levator aponeurosis by plication. A wedge resection of the lateral third of the upper lid shortened the horizontal width and also changed the unpleasant fan shape to a better shape, with a natural curvature of the lid. The authors also performed a 5-mm transconjunctival tarsectomy. Visual impairment was corrected with a satisfactory aesthetic outcome.     

Free-floating ball thrombus in the left atrium

 Free-floating ball thrombi in the left atrium are rarely seen. They can cause sudden death by occluding the mitral valve. A 47-year-old female patient who showed signs of mitral stenosis during a physical examination and atrial fibrillation by electrocardiography was not administered anticoagulant therapy. On the transthoracic echocardiogram, a stenotic mitral valve and a floating mobile mass were seen inside the large left atrium. This mass was rounded (ball-like), had smooth contours, and occasionally occluded the stenotic mitral valve. The patient underwent emergency surgery to remove the mass, which was later proven to be a thrombus pathologically. Additionally, mitral valve replacement was performed. The importance of anticoagulant therapy for patients with rheumatic mitral stenosis has been emphasized by this case. Received: January 30, 2002 / Accepted: March 23, 2002     

Surgical treatment of thoracic outlet syndrome: effect and results of surgery

BACKGROUND: Because of the difficulty in diagnosis and different treatment options, debate on thoracic outlet syndrome (TOS) has continued. Our aim is to report our surgical experience. METHODS: Forty-seven patients with thoracic outlet syndrome were operated on between 1985 and 2000. Mean age was 37.9 years (range, 17 to 58 years); female/male ratio was 41/6. The most frequent symptom was paresthesia (72.3%). Seventeen patients (36%) had bilateral symptoms. Of all, 89.3% (42 cases) were neurologic thoracic outlet syndrome, and 10.7% (five cases) were vascular. Lower plexus (C8-T1/ulnar nerve) compression was present in 36 patients and upper plexus (C5-C7/median nerve) compression in 6 patients. Doppler ultrasonography in 11 patients, angiography in 8, and lymph node scintigraphy in 1 patient were also performed. Main operative indications were persistence of symptoms after conservative therapy and reduced (< 60 m/s) ulnar nerve conduction velocity. RESULTS: Fifty-five operations were performed on the 47 patients. First (59.6%) and cervical costae (21.3%) resections were the most frequent operations. Mean ulnar nerve conduction velocity was 54.8 m/s (range, 43 to 68 m/s) preoperatively and 69.4 m/s (range, 47 to 70 m/s) postoperatively (p < 0.05). The morbidity rate was 17% (8 of 47). No difference was observed between transaxillary and supraclavicular incisions. No brachial plexus injuries occurred. The most frequent cause of morbidity was incisional pain. Two reoperations were performed for recurrences. Follow-up was 4.6 years, and 75% of lower plexus and 50% of upper plexus compressions remained asymptomatic. Severe and long-term pain occurred in 1 patient. CONCLUSIONS: Surgical decompression for thoracic outlet syndrome is efficient and dependable, but results deteriorate over time.     

A new technique for superior hypogastric plexus block: the posteromedian transdiscal approach

Superior hypogastric plexus block has been advocated for the treatment of cancer related pelvic pain. Neurolysis is usually established using the classical posterolateral approach in the prone position, in which correct placement of the needle is sometimes difficult due to vertebral anatomy and the patient's inability to lie prone. We describe an alternative posteromedian transdiscal approach under fluoroscopic guidance for the treatment of intractable pelvic pain in three patients, in whom the classical approach was not possible. The L5-S1 interdiscal space was identified with fluoroscopy. The needle was then introduced through the disc and advanced under lateral fluoroscopic control. After verifying correct needle placement, neurolysis was performed with 8 ml of 10% phenol solution. All patients had significant pain relief immediately after the block, lasting from 6 to 12 months, and their pain severity scores and opioid consumption were reduced by more than 50%. There were no complications such as discitis, disc rupture or nerve injury. Since this new posteromedian transdiscal approach provides easy access to the superior hypogastric plexus with a single puncture and with any patient position, it may be an alternative to the classical approach.