Preparation and non-invasive in-vivo imaging of anti-adhesion barriers with fluorescent polymeric marks.

Comb-like PEMLn polymers with pendent PEG-PLLA side chains were synthesized as tissue anti-adhesion barriers. The comb-like structure improved the flexibility of the films. Fluorescent polymer-biocompatible polymer guest-host materials were printed on the films as marking dots. Without sacrificing rats on different days after surgery, degradation behaviors of the marked films can be investigated non-invasively in the in-vivo imaging system (IVIS) by monitoring the location of fluorescent signals. Degradation properties of PEML1/G26L35 films were adjusted by incorporating G26L35 oligomers. PEML1 and PEML1/G26L35 films were very effective in preventing post-surgical tissue-adhesions. Degradation behaviors of various films observed in the animal study were consistent with those investigated by the in-vivo imaging method. Fluorescent polymer/biocompatible polymer blends were promising candidates for in-vivo imaging applications.

Comparison of the effectiveness of autologous fibrin glue and macroporous biphasic calcium phosphate as carriers in the osteogenesis process with or without mesenchymal stem cells.

BACKGROUND: Facial bone reconstruction has been a challenge for oral and maxillofacial surgeons for a long time. Recently, some studies have reported the use of stem cells in facial reconstruction to achieve osteogenesis. However, to ensure that stem cells remain in the recipient site, a biocompatible carrier is needed to transfer the stem cells. Fibrin glue has been shown to promote hemostasis in wound management and accelerate soft tissue healing, but the role of fibrin glue in bone regeneration remains debatable. The purpose of this study was to compare the effectiveness of autologous fibrin glue and macroporous biphasic calcium phosphate (MBCP) as carriers in the osteogenesis process with/without mesenchymal stem cells. METHODS: Fifteen New Zealand white rabbits were used in this study. Mesenchymal stem cells were harvested from the iliac bone, and autologous fibrin glue was made from peripheral blood. Three cranial defects with a diameter of 6 mm were created over the cranial bone in each rabbit. The 15 animals were separated into 2 groups. The first group contained 12 rabbits. The grafted substances placed over the regions of defect were: (1) stem cells plus autologous fibrin glue; (2) stem cells plus MBCP; (3) defect alone as control. In the second group of 3 rabbits, the cranial defects were grafted with: (1) autologous fibrin glue alone; (2) MBCP alone; (3) defect alone as control. Rabbits were sacrificed at 1, 2 and 3 months post operation. Radiography and histology were used to detect bone formation. RESULTS: Stem cells plus autologous fibrin glue induced more bone formation 2 months post operation and more mature bone was found 3 months post operation compared with the other groups. MBCP with or without stem cells showed moderate tissue reaction, including giant cell, histiocyte and eosinophil cell accumulation. CONCLUSION: Using stem cells plus autologous fibrin glue as the carrier may accelerate new bone regeneration.

Color Doppler US pulmonary artery vessel signal: a sign for predicting the benign lesions.

The lung cancer blood supply originates from the bronchial artery. If vessel signals within pulmonary lesions can be confirmed to be those of the pulmonary artery, color Doppler ultrasound (US) should be able to predict and differentiate benign lesions from lung cancers. Two hundred sixty-four patients with abutting thoracic lesions (including 125 lung cancers and 139 benign lesions) underwent color Doppler US examinations. A pulsatile flow, with the vessel signal length on sonographic appearance > or =1 cm demonstrated by color Doppler US, was arbitrarily defined as a pulmonary artery vessel signal. Of the 264 thoracic lesions, 73 (58%) lung cancers and 107 (77%) benign lesions had detectable color Doppler US pulsatile flow vessel signals. Analyzing the pulsatile flow vessel signals, the color Doppler US pulmonary artery vessel signal was present in 74 (53%) benign lesions, but was found in only two (2%) lung cancers of a specific alveolar cell carcinoma with lobar consolidation. Using the pulmonary artery vessel signal, color Doppler US can be valuable in predicting and differentiating benign lesions from lung cancers (p < 0.0001, sensitivity = 0.53, specificity = 0.98 and positive likelihood ratio 26.5). In conclusion, color Doppler US pulmonary artery vessel signal sign is useful in predicting and differentiating benign lesions from lung cancers.

Histopathology of radiation necrosis with severe peritumoral edema after gamma knife radiosurgery for parasagittal meningioma. A report of two cases.

BACKGROUND: Gamma knife radiosurgery (GKS) has been an effective treatment for meningiomas. Nevertheless, it still has certain risks. We present 2 cases of parasagittal meningioma after GKS complicated with radiation necrosis and peritumoral edema. The results of histologic examination are discussed. CASE DESCRIPTION: Two cases of parasagittal meningioma received GKS. Symptomatic peritumoral edema developed 3-4 months after GKS. Both of them underwent surgical resection of their tumor afterwards. Histologic examination showed necrotic change inside the tumor and infiltration of inflammatory cells in both cases. Hyalinization of blood vessels was seen in the 2nd case. The patients had improvement of neurologic function after surgical resection. Imaging performed 3 months after surgical resection showed alleviation of brain edema. CONCLUSION: After radiosurgery peritumoral edema tends to occur in meningiomas with a parasagittal position. Radiation necrosis, infiltration of inflammatory cells, and radiation injury to the vasculature causing hyalinization of blood vessels are suggested as the underlying histopathology.

Lipoma of the palatine tonsil.

Lipomas are benign tumors composed of mature fat cells. They occur frequently in subcutaneous tissue but rarely in the upper aerodigestive tract. Tonsillar lipomas are rare. To our knowledge, there are only six documented cases in the English literature. Here, we present the case of a 46-year-old Taiwanese female with a submerged oval yellowish mass in her left palatine tonsil. She received tonsillectomy and the pathologic diagnosis was tonsillar lipoma. The clinical presentation, management and literature review are also presented.

Comparison of animal models with soft tissue infection by different bacilli.

In clinical medicine improved diagnostic methods for the detection of infection are needed. A good infectious animal model is very important for the development of a new diagnostic method or drug. The purpose of this study was to establish a good animal model with soft tissue infection. Twenty-four SD rats were divided into four groups (6 in each group). Various bacilli including Staphylococcus aureus (S. aureus), Streptococcus pneumoniae (S. pneumoniae), and Escherichia coli (E. coli) were injected intramuscularly into the left caudal thighs of three groups of rats to create soft tissue infection. In addition, normal saline was injected into the left caudal thighs of ten rats which were used as controls. Before and 48 hr after inoculation of the bacilli, a blood sample (0.5 ml) was taken from each rat and analyzed to determine the white blood cell count and differentiated cell count. In addition, 48 hr after the inoculation, 0.2 mCi of gallium-67 was injected via the tail vein. Gallium scan was performed at 24 hr and 48 hr after administration of the radiotracer. The dorsal view of both hind legs was imaged and analyzed by computers to calculate the lesion-to-normal (L/N) ratio. After imaging, all rats were sacrificed and specimens from portions of the infected thigh muscle were sent for histopathologic investigation to confirm the infection. The increase in both the WBC counts and the segmented polymorphonuclear leukocytes (PMNs) were most significant in the S. aureus group, followed by the S. pneumoniae group, E. coli group and normal control groups. The rats with S. aureus infection had significant gallium uptake at the site of infection and the highest L/N ratio of 2.14 on the 24-hr image and 2.0 on the 48-hr image. The rats with S. pneumoniae had the second highest L/N ratio (1.41 at 24 hr, and 1.48 at 48 hr). The L/N ratio for the E. coli group was 1.27 at 24 hr and 1.35 at 48 hr. No obviously abnormal gallium uptake was demonstrated in the normal controls. We conclude that all three bacilli induced a soft tissue infection in SD rats. S. aureus resulted in the most significant infectious signs.

Significance of expression of human METCAM/MUC18 in nasopharyngeal carcinomas and metastatic lesions.

Human METCAM/MUC18, a cell adhesion molecule (CAM) in the immunoglobulin-like gene super family, plays a dual role in the progression of several epithelium cancers; however, its role in the nasopharyngeal carcinoma (NPC) remains unclear. To initiate the study we determined human METCAM/MUC18 expression in tissue samples of normal nasopharynx (NP), NPCs, and metastatic lesions, and in two established NPC cell lines. Immunoblotting analysis was used for the determination in lysates of frozen tissues, and immunohistochemistry (IHC) for expression in formalin-fixed, paraffin-embedded tissue sections of 7 normal nasopharynx specimens, 94 NPC tissue specimens, and 3 metastatic lesions. Human METCAM/MUC18 was expressed in 100% of the normal NP, not expressed in 73% of NPC specimens (or expressed at very low levels in only about 27% of NPC specimens), and expressed again in all of the metastatic lesions. The level of human METCAM/MUC18 expression in NPC tissues was about one fifth of that in the normal NP and metastatic lesions. The low level of human METCAM/ MUC18 expression in NPC specimens was confirmed by a weak signal of RT-PCR amplification of the mRNA. Low expression levels of human METCAM/MUC18 in NPC tissues were also reflected in the seven established NPC cell lines. These findings provided the first evidence that diminished expression of human METCAM/MUC18 is an indicator for the emergence of NPC, but increased expression then occurs with metastatic progression, suggesting that huMETCAM/MUC18, perhaps similar to TGF-ß, may be a tumor suppressor, but a metastasis promoter for NPC.

Novel application of artificial dermis plus autologous vital epithelial cells: improved wound epithelialization.

The purpose of this study was to evaluate artificial dermis with the simultaneous addition of autologous epithelial cells for oral lesion defect reconstruction. Surgical wounds reconstructed with artificial dermis plus scraped epithelial cells were evaluated in 5 patients with oral benign lesions or squamous cell carcinoma. Clinical follow-up indices included scar formation and tissue surface texture observation. The neomucosal layers were analyzed histologically to establish the degree of epithelialization. Clinical observation showed that the oral mucosal texture was smoother in artificial dermis with added epithelial cells at 4 weeks postoperation compared with artificial dermis alone. The wound contraction and scar formation processes were slow. Viable epithelial cells with flat rete ridges remained in the artificial dermis, and a neoepithelial layer was present in the histological findings. We showed that healthy granulation tissue and neoepithelial formation in artificial dermis with epithelial cells was beneficial for the repair of oral defects. Scraping oral epithelial cells and applying them to artificial dermis assisted in the early preparation of composite grafts and minimized requirement for donor sites. This technique may improve the treatment of patients with oral benign tumors and early-stage squamous cell carcinoma.

Surgical-pathologic factors affect long-term outcomes in stage IB (pT2 N0 M0) non-small cell lung cancer: a heterogeneous disease.

OBJECTIVES: Our objective was to identify surgical-pathologic factors affecting prognosis in stage IB non-small cell lung cancers. METHODS: Between 1997 and 2006, a cohort of 272 cases of pT2 N0 M0 stage lung cancer were retrospectively analyzed. The patients included 70 women and 202 men with a mean age of 67.0 years. The surgical resections included pneumonectomy in 4, bilobectomy or lobectomy in 217, and limited resections in another 51. The impact of surgical-pathologic characteristics on survival, including cell type, tumor differentiation, tumor size, depth of visceral pleural invasion, type of surgical resection, and extent of lymphadenectomy on patient survival, was compared accordingly. RESULTS: Tumor types included adenocarcinoma/bronchioloalveolar carcinoma in 142, squamous cell carcinoma in 100, and others in 30. Cell differentiations were classified as well, moderately, and poorly differentiated in 23, 151, and 92 cases, respectively. The mean tumor size was 3.9 cm in diameter, and the average resected lymph node number was 14.3. Direct visceral pleural or subpleural invasions (<1 mm) were found in 134 and 42 cases, respectively. Angiolymphatic invasions were seen in 26 cases, and positive tumor margins were found in 14 cases. The overall 5-year and 10-year survivals were 59.5% and 41.3%, respectively. Good prognostic factors using univariate analysis included female gender, nonlimited resection, well-differentiated tumor, no angiolymphatic invasion, smaller size (14 nodes). However, the Cox proportional hazard model revealed female gender, well-differentiated tumor, no pleural involvement, no angiolymphatic invasion, and more than 14 nodes retrieved as independent good prognostic factors. CONCLUSIONS: Stage IB lung cancer can be treated by standard pulmonary resection accompanied by adequate mediastinal lymphadenectomy. Owing to the heterogeneity of stage IB lung cancer and the fact that prognosis can be affected by many surgical-pathologic factors, refinement of the current TNM staging criteria may be needed.

Microvascular density and vascular endothelial growth factor immunoreactivity as predictors of regional lymph node metastasis from betel-associated oral squamous cell carcinoma.

PURPOSE: Neovascularization has profound effects on tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is a mitogen that acts exclusively on endothelial cells. The roles of miscrovascularity density (MVD) and VEGF expression in the progression of oral squamous cell carcinoma (OSCC) have been controversial. The purpose of the present study was to measure the MVD and VEGF expression in a cohort of patients with betel-associated OSCC and to evaluate for possible clinicopathologic correlations. PATIENTS AND METHODS: The paraffin sections from 49 subjects with OSCC were subjected to immunohistochemical studies to measure the highest MVD (h-MVD) and cytoplasmic immunoreactivity of VEGF. The findings in the tissue samples were analyzed with regard to the patients' risk factors and clinical course. RESULTS: The OSCC samples had an average h-MVD score of 27.7/mm(2). VEGF immunoreactivity was positive in 75.5% of samples. Both h-MVD and VEGF immunoreactivity were statistically associated with lymph node metastasis (P =.012 and.037, respectively). A marginally significant association was also noted between the h-MVD and patient survival (P =.056). The age and oral habits of patients, as well as the tumor site and size, did not appear to be correlated with h-MVD or VEGF immunoreactivity. CONCLUSION: The data suggest that both h-MVD and VEGF immunoreactivity may be useful predictors for the progression of a subset of OSCC associated mostly with betel use. Antiangiogenesis therapy might have a role in reducing regional metastasis.

Intraventricular malignant meningioma: one case report.

We report a case of primary intraventricular malignant meningioma in a 74-year-old man who presented with progressive weakness of the left limbs and dizziness, The preoperative magnetic resonance (MR) imaging of the head initially suggested that a glioblastoma multiforme or a metastatic lesion might be present. But later, the excised tumor was histologically diagnosed as a primary malignant meningioma. So far, only a few cases of intraventricular malignant meningioma have been reported. The MR imaging of this tumor has rarely been described in the literature. In the present case, the mass lesion showed hyperintensity on the T1-weighted image (T1WI) and hypointensity on the T2-weighted image (T2WI) which was not commonly seen in meningioma. The unusual MR imaging of this case may be attributed to the intratumoral hemorrhage. Although intraventricular malignant meningioma is difficult to diagnose based on MR or computed tomographic images alone, the characteristics of the MR images in the present case may offer an option for preoperative differential diagnosis of intraventricular tumors.

The molecular markers for prognostic evaluation of areca-associated buccal squamous cell carcinoma.

BACKGROUND: Buccal squamous cell carcinoma (BSCC) is the most frequently occurring oral cancer in Asians due to the popularity of areca use in this area. The aim of the present study was to evaluate the survival of areca-associated BSCC associated with multiple molecular markers. METHODS: Using immunohistochemistry, we evaluated the survival of a cohort of 55 patients with BSCC being followed long term, as correlated to the expression of variable markers. RESULTS: We found that p53, p21, Rb, cyclin D1 (CCD1), MDM2, and gamma-catenin were positive in 81, 60, 70, 31, 88, and 44% of patients, respectively. Subjects with -ve immunoreactivity for CCD1, and +ve immunoreactivity for MDM2 and gamma-catenin had significantly better survival than subjects with the opposite immunoreactive pattern. KAPLAN-meier survival curves confirmed this association. CONCLUSION: The data indicate that expression of CCD1, MDM2, and gamma-catenin might serve as potential prognostic markers for BSCC in areca-using patients.