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This paper presents an investigation into the reliability of substrate bonding between metal layers and gallium arsenide vertical-injection light-emitting diodes (GaAs VLEDs). In this study, molybdenum (Mo) acts as a buffer layer between the GaAs VLED and the aluminum-based metal core printed circuit board (MCPCB). The thermal expansion coefficient (CTE) value of GaAs is approximately equal to that of the Mo layer under the substrate. This is beneficial for slowing the decay of the adhesive bond due to temperature cycling from − 40°C to 125°C for 50 cycles. The experimental results show that the use of the Mo buffer layer greatly improved the electrical and optical performance of the LED packages. The average leakage current was reduced from 33.63 mA to 2.37 mA at the reversed voltage of − 3 V and the increase in light output power was 130% at an injection current of 0.7 A. The results also show that a Mo buffer layer can reduce the risk of cracking on bonding wires after the thermal shock test (TST). These results are useful for improving the aging of GaAs VLEDs.

Nine autosomal dominant spinocerebellar ataxias (SCAs) are caused by an abnormal expansion of CAG trinucleotide repeats that encodes a polyglutamine (polyQ) tract within different genes. Accumulation of aggregated mutant proteins is a common feature of polyQ diseases, leading to progressive neuronal dysfunction and degeneration. SCA type 3 (SCA3), the most common form of SCA worldwide, is characterized by a CAG triplet expansion in chromosome 14q32.1 ATXN3 gene. As accumulation of the mutated polyQ protein is a possible initial event in the pathogenic cascade, clearance of aggregated protein by ubiquitin proteasome system (UPS) has been proposed to inhibit downstream detrimental events and suppress neuronal cell death. In this study, Chinese herbal medicine (CHM) extracts were studied for their proteasome-activating, polyQ aggregation-inhibitory and neuroprotective effects in GFPu and ATXN3/Q[Formula: see text]-GFP 293/SH-SY5Y cells. Among the 14 tested extracts, 8 displayed increased proteasome activity, which was confirmed by 20S proteasome activity assay and analysis of ubiquitinated and fused GFP proteins in GFPu cells. All the eight extracts displayed good aggregation-inhibitory potential when tested in ATXN3/Q[Formula: see text]-GFP 293 cells. Among them, neuroprotective effects of five selected extracts were shown by analyses of polyQ aggregation, neurite outgrowth, caspase 3 and proteasome activities, and ATXN3-GFP, ubiquitin, BCL2 and BAX protein levels in neuronal differentiated ATXN3/Q[Formula: see text]-GFP SH-SY5Y cells. Finally, enhanced proteasome function, anti-oxidative activity and neuroprotection of catalpol, puerarin and daidzein (active constituents of Rehmannia glutinosa and Pueraria lobata) were demonstrated in GFPu and/or ATXN3/Q[Formula: see text]-GFP 293/SH-SY5Y cells. This study may have therapeutic implication in polyQ-mediated disorders.

A major obstacle for using human pluripotent stem cells (hPSCs) derived vascular cells for cell therapy is the lack of simple, cost-saving, and scalable methods for cell production. Here we described a simplified and chemically defined medium (AATS) for endothelial cells (ECs) and smooth muscle cells (SMCs) differentiation. AATS medium does not contain insulin, enabling the rapid and highly efficient vascular mesoderm formation through accelerating metabolic and autophagy-enhanced mesoderm induction. Transcriptome profiling confirmed that hPSC-derived ECs and SMCs in the AATS medium closely resembled primary ECs and SMCs formed in vivo. ECs appeared to adhere and grow better in the AATS medium over other cell types, which allowed the purification of CD31+CD144+ double-positive cells. Furthermore, the AATS medium was compatible with 3D microscaffold (MS) culture, which may facilitate large-scale bioproduction of ECs. HPSC-derived ECs and SMCs in the AATS medium exhibited strong revascularization potential in treating murine ischemic models. Our study provided a cost-effective and efficient medium system to manufacture GMP compatible, off-the-shelf ECs, and SMCs to model human diseases and vascular repair.

Our laboratory has previously revealed the use of metal-semiconductor-metal (MSM) varactors against malicious pulses, as well as completed the related verification and measurements of such a circuit. To improve the reliability of this protection module further, in this study, we deposited a gallium oxide (Ga2O3) thin film in between the Schottky contact electrode to manufacture a metal-oxide-semiconductor-oxide-metal (MOSOM) varactor. However, the thin-film quality and heterojunction interfaces will affect these fabricated varactors in various ways, such as the asymmetry threshold voltage to the variable capacitance characteristics. This study aims to address the issues associated with the inserted oxide thin film, as well as to determine how improvements could be obtained by using an oxygen furnace annealing process. As a result, the breakdown voltage of the MOSOM varactor was further promoted and a more robust anti-surge module was thus realized.

Background Hematopoietic lineage cells derived from human pluripotent stem cells (hPSCs) hold great promise for the treatment of hematological diseases and providing sufficient cells for immune therapy. However, a simple, cost-effective method to generate large quantities of hematopoietic stem/progenitor cells (HSPCs) is not yet available. Methods We established a monolayer, chemically defined culture system to induce hematopoietic differentiation from hPSCs in 8 days. Results We found that insulin-free medium allowed hPSCs to leave pluripotency promptly and preferably enter the vascular lineage. Addition of insulin during the later stage of differentiation was essential for the efficient induction of hemogenic endothelium and the emergence of large numbers of CD34+CD43+ HSPCs, while no insulin condition preferably permits endothelial differentiation. Global transcriptome profiling revealed that HSPCs differentiated using our protocol were similar to embryoid body-derived HSPCs. HSPCs obtained from our differentiation system formed robust erythroid, granulocyte and monocyte/macrophage colonies in CFU assay, and can be induced to generate functional macrophages with robust phagocytic ability. Conclusion Our results demonstrated that proper manipulation of insulin-mTOR signaling can greatly facilitate HSPC formation. This finding can be further exploited to formulate cost-effective differentiation medium to generate large quantities of cells of desired blood lineages for regenerative medicine. Electronic supplementary material The online version of this article (10.1186/s13287-018-0934-x) contains supplementary material, which is available to authorized users.

BACKGROUND Pharyngoesophageal defects are traditionally reconstructed with jejunal or radial forearm flaps. Recently, anterolateral thigh flaps have served for pharyngoesophageal reconstruction. We tell of our experience with anterolateral thigh flap for the reconstruction of pharyngoesophageal defect for the past 5 years. This study presents another modified flap design and refinement of surgical techniques. METHODS In all, 45 pharyngoesophageal reconstructions were performed during 2006 to 2011, namely patch (n = 18), near-circumferential (n = 8), and circumferential defect (n = 19) reconstructed by 2 plastic surgeons with the same trapezoid anterolateral thigh flap design. RESULTS Total flap loss occurred in 2 patients (4%). Two patients experienced partial flap necrosis. Fistulas occurred in 8 patients, but only 5 of these needed further suture ligation or local flap treatment. Postoperative strictures without tumor recurrence were identified in 4 patients (9%). Forty patients (88.9%) could tolerate oral diet; 34 of these ate soft or solid food. CONCLUSIONS Anterolateral thigh flap offers good coverage and swallowing function in the reconstruction of hypopharyngeal defect. Trapezoid drawing of anterolateral thigh flap makes the design simplified, with an accepted complication rate.

Kawasaki disease (KD) is a systemic vasculitis which presents with stable vital signs. Shock rarely occurs in such cases, but it may occur in the acute phase of KD. This report describes a 7-year-old boy with KD shock syndrome (KDSS) who presented with persistent fever, injected conjunctiva, a polymorphic skin rash, echocardiography indicating coronary artery dilatation, and shock. The patient's haemodynamic status markedly improved with immunoglobulin therapy. Early recognition of KDSS can be challenging; however, delay in diagnosis can increase the risk of coronary artery abnormalities and death.

BACKGROUND It is not always possible to use the anatomically variable free anterolateral thigh (ALT) flap for reconstructive surgery. An anteromedial thigh (AMT) flap serves as a good alternative, and shares the same vascular pedicle as the ALT flap. METHODS Of 698 reconstructions performed in 2006 to 2013 following head and neck tumor ablation surgery, ALT flaps were used in 653 patients. Eighteen free AMT flaps were harvested to replace variant nonviable ALT flaps. RESULTS The lack of a sizable perforator in the ALT flap territory was the main reason for changing the reconstruction plan. Anteromedial thigh flap size ranged from 10 × 4 to 30 × 8 cm. The flap survival rate was 100%. The follow-up period ranged from 3 to 56 months. CONCLUSION During head and neck reconstruction, when no sizable perforator is available during harvest of the ALT flap, successful reconstruction can be achieved using the ipsilateral AMT flap without additional donor-site morbidity.

This paper investigates and evaluates analog and digital low-dropout linear voltage regulators (LDO) with FinFET, TFET and hybrid TFET-FinFET implementations. We utilize Sentaurus physics-based atomistic 3D TCAD mixed-mode simulations for device characteristics and HSPICE with look-up tables based on Verilog-A models calibrated with TCAD simulation results. Frequency response, load regulation and power supply rejection ratio (PSRR) are evaluated for analog LDOs under low, medium and high bias-current conditions. The results indicate that for analog implementations, TFET-LDO and hybrid-LDO provide better loop-gain and PSRR than FinFET-LDO under low and medium operating currents, whereas at higher operating current, FinFET implementation would outperform. As operating voltage is reduced, the performances of analog implementations degrade, and digital implementations become favorable for VIN below around 0.55V. We further show that for digital LDO, all FinFET implementation provides superior performance over all TFET and hybrid TFET-FinFET implementations.

Management of an infected groin wound after vascular surgery may be a challenge. We report a retrospective series of cases of the management of groin defects and an algorithm for their management based on our own experience and related literature.We conducted a retrospective chart review from June 2008 to February 2012 of patients with infected groin wounds after vascular surgical procedures. The review disclosed six patients with a history of femoral cannulation or extracorporeal membrane oxygenation (ECMO), one patient with a femorofemoral bypass, one patient with an intra-aortic balloon pump (IABP), and one patient with a thoracoabdominal aneurysm following stent implantation. Exposure of femoral vessels was noted in seven of these nine patients, and wound cultures of all nine patients yielded positive results.The mean age of the nine patients (five males and four females) was 54.6 years (range 17-79 years). The mean follow-up was 13.6 months (range 8-30 months). Four of the patients were treated with a pedicled gracilis flap; one with a local flap; one with a myocutaneous flap of the anterolateral thigh (ALT) combined with a partial tensor fascia lata (TFL) flap; one with primary closure; and two with a myocutaneous island pedicle flap of the ALT. No donor-site complications were noted. There was partial skin cyanosis in the patient treated with a myocutaneous flap of the ALT combined with a TFL flap, which resolved after one week. The scheduled follow-up of the patients showed that all of their groin wounds had healed well.A pedicled flap of gracilis muscle is an ideal and effective option for covering infected groin wounds of10 cm with exposure of femoral vessels. According to a literature review, a sartorius muscle flap is another option for accomplishing this. A myocutaneous island flap of the ALT is indicated for infected groin wounds10 cm with exposure of femoral vessels. The literature indicates that myocutaneous flaps of rectus abdominis (RA) muscle and flaps of rectus femoris (RF) muscle are also suitable for groin wounds larger than 10 cm. Bilateral flaps of ALT and bilateral myocutaneous flaps of RA or RF muscle are suggested for the reconstruction of bilateral groin wounds. For infected groin wounds without exposure of femoral vessels, a local flap or primary closure are suggested, depending on the size of the defect.

Human recombinant bone morphogenetic protein 2 (rhBMP-2) accelerates bone regeneration but is associated with limited cementum and periodontal ligament regeneration, local root resorption, and ankylosis. This study assessed a new approach to the regeneration of the alveolar bone and periodontal attachment apparatus using a combination of ex vivo autologous bone marrow mesenchymal stem cells (MSCs) engineered by replication defective adenovirus to express the BMP-2 gene and pluronic F127 (PF127) in a large mammalian animal model. Bilateral maxillary periodontal defects were created over the premolar area in 9 mature male miniature swine. The 18 defects were randomly assigned to receive either BMP-2-expressing MSCs in the advBMP-2 group or MSCs alone in the MSC group. The regenerated periodontal attachment apparatus was evaluated histologically, and the total regenerated bone volume was calculated from three-dimensional computed tomography analysis. Three months after implantation, significant bone volume was regenerated in the advBMP-2 group. Periodontal apparatus regeneration was significantly better in the advBMP-2 group. New cementum and Sharpey fibers were observed on the denuded root surfaces in the advBMP-2 group, whereas incomplete healing with localized root surface resorption was noted in the control group. The use of ex vivo BMP-2-engineered autologous MSCs enhanced bone and periodontal apparatus regeneration in maxillary alveolar and periodontal defects in swine. This novel integrated approach might be suitable for clinical periodontal apparatus repair. This may be an alternative for cleft alveolar bone graft surgery.

This study proposes a concept extraction and clustering method, which improves Topic Keyword Clustering by using Log Likelihood Ratio for semantic correlation and Bisection K-Means for document clustering. Two value-added services are proposed to show how this approach can benefit information retrieval (IR) systems. The first service focuses on the organization and visual presentation of search results by clustering and bibliographic coupling. The second one aims at constructing virtual research communities and recommending significant papers to researchers. In addition to the two services, this study conducts quantitative and qualitative evaluations to show the feasibility of the proposed method; moreover, comparison with the previous approach is also performed. The experimental results show that the accuracy of the proposed method for search result organization reaches 80%, outperforming Topic Keyword Clustering. Both the precision and recall of virtual community construction are higher than 70%, and the accuracy of paper recommendation is almost 90%.

Plastic surgeons reconstruct hard and soft tissues in many parts of the human body. Penile reconstruction is unique in that the target tissue has to be soft but intermittently rigid. There are many ways to treat penile defects. The ideal reconstruction must take into considerations sensation, cosmesis, and erectile functions. There is limited literature available on the management of penile glans defect. In this report, we present the reconstruction of penile glans defect, after surgical excision of Bowen disease, using a bipedicled foreskin flap of bucket handle type. It is easy to perform and highly effective, and importantly, both cosmetic and functional outcomes at 1-year follow-up were quite satisfactory.

Natural bone is comprised of nanosized blade-like crystals of hydroxyapatite grown in close contact with collagen (Col) fibers. Characteristics of artificial bone tissue differ considerably with those of natural ones, mainly from the unusual self-organizing interaction between the apatite crystals and the proteic components. Nanoparticle spheres of hydroxyapatite (n-HA), dispersed in reconstituted fibrous Col, were prepared in three weight ratios of 75:25, 65:35, and 50:50 (n-HA:Col). Bone marrow mesenchymal stem cells (MSCs) from rabbits were seeded and cultured on the n-HA/Col microbeads and characterized. n-HA were evenly distributed throughout the Col matrix and aggregated to microbeads as determined by scanning electron microscopy. Electron and confocal microscopy showed that the MSCs spread and attached to microbeads via focal adhesions, while staining for F-actin and DNA revealed the presence of stress fibers. The phenotype of the MSCs in the flow cytometry was identified as CD11a-, CD44+, and CD90.1+. The optimal weight ratio is 65:35 for the normalized alkaline phosphatase activities. The transduced MSCs, engineered by replication-defective adenovirus to express the BMP-2 gene, demonstrated synergic osteogenic effects in the microbeads. MSCs are capable of proliferating and differentiating in appropriate combinations of n-HA/Col. Thus it is a promising composite for future clinical applications.

Computer applications in head and neck reconstruction are rapidly emerging and create not only a virtual environment for presurgical planning, but also help in image-guided navigational surgery. This study evaluates the use of prefabricated 3-dimensional (3D) mirror image templates made by computer-simulated adjusted occlusions to assist in microvascular prefabricated flap insertion during reconstructive surgery. Five patients underwent tumor ablation surgery in 1999 and survived for 8 years. Four of the patients with malignancy received radiation therapy. All patients in this study suffered from severe malocclusion causing trismus, headache, temporomandibular joint pain, an unsymmetrical face, and the inability of further osseointegrated teeth insertion. They underwent a 3D computer tomography examination and the nonprocessed raw data were sent for computer simulation in adjusting occlusion; thus, a mirror image template could be fabricated for microsurgical flap guidance. The computer simulated occlusion was acceptable and facial symmetry obtained. The use of the template resulted in a shorter operation time and recovery was as expected. The computer-simulated occlusion-adjusted 3D mirror image templates aid in the use of free vascularized bone flaps for restoring continuity to the mandible. The coordinated arch will help with further osseointegration teeth insertion.

Autologous vascularized bone grafts, allografts, and biocompatible artificial bone substitutes each have their shortcomings. Bones regenerated using recombinant human bone morphogenetic proteins, demineralized bone powder, or combinations of these are generally small and do not meet the need. The current trend is to use tissue engineering approaches with bone marrow mesenchymal stem cells (MSCs) to generate bones of a desired size and shape. A suspension of osteogenically induced MSCs (CD11a-, CD29+, CD44+) was added to 2% alginate, gelled by mixing this combination with calcium sulfate (CaSO(4) 0.2 g/mL), and injected into the subcutaneous pocket in the dorsal aspect of nude mice. Cells of various concentrations (0, 10, 50, and 70 million/mL) were used. These implanted constructs were harvested at predetermined times up to 30 weeks for histology. The doubling time of bovine MSCs is 3.75 +/- 1.96 days and the proliferation is rapid. Histological evaluation revealed signs of endochondrosis with woven bone deposition. The equilibrium modulus increased with time in vivo, though less than that of normal tissue. Implants seeded with 70 million cells/mL for 6 months resulted in the best formation of equilibrium modulus. This approach has several advantages: (i) obtaining MSCs is associated with low donor morbidity; (ii) MSCs proliferate rapidly in vitro, and a large number of viable cells can be obtained; and (iii) the MSC/alginate constructs can develop into bone-like nodules with high cell viability. Such a system may be useful in large-scale production of bony implants or in the repair of bony defects. The fact that endochondral bone formation led to woven bone suggests its potential feasibility in regional cell therapy.

Primary osteosarcoma of the calvarium is rare. A 22-year-old female patient was admitted for a progressively enlarging, indurated mass under her scalp for 6 months. A computed tomographic scan revealed a 4 x 3 x 2-cm3 osteolytic lesion over the right parietal cortex with a sunburst appearance. The patient underwent en bloc tumor resection using bicortical parietal craniectomy with a 2-cm margin of normal bone, including the tightly adherent periosteum over the tumor. Immediate cranioplasty was performed with split-thickness autogenous calvarial bone grafts. Histopathologic examination showed the tumor to be a primary high-grade osteosarcoma of the skull. She received postoperative chemotherapy. She has recovered well and remains without any evidence of disease at her most recent, 8-year follow-up. The key to disease-free survival in treating primary osteosarcoma of the calvarium is complete surgical resection with immediate reconstruction followed by adjuvant chemotherapy.

The regeneration of the periodontal attachment apparatus remains clinically challenging because of the involvement of three tissue types and the complexity of their relationship. Human recombinant bone morphogenic protein-2 (rhBMP-2) can accelerate the regeneration of bone and cementum and the insertion of periodontal ligament fibers but may lead to a deranged periodontal relationship, ankylosis and root resorption.This study evaluated a novel approach to regeneration of the periodontal attachment apparatus using a combination of ex vivo autologous bone marrow mesenchymal stem cells (MSCs) engineered by replication-defective adenovirus to express the BMP-2 gene and Pluronic F127 (PF127). Twenty-four periodontal defects were surgically created in 12 New Zealand white rabbits and randomly assigned to three experimental groups with MSCs: the advBMP-2 group; the advbetagal group; the MSC group and one control group: PF127 only. The regenerated periodontal attachment apparatus was assessed histologically and the total regenerated bone volume was calculated from three-dimensional computed tomography analysis.This approach regenerated not only cementum with Sharpey's fiber insertion, but also statistically significant quantities of bone, re-establishing a more normal relationship among the components of the regenerated periodontal attachment apparatus, which is beneficial for the maintenance of periodontal health.Ex vivo gene transfer using stem cells as vectors may provide an advantage of slower BMP-2 release, increasing cementogenesis. There is regeneration of the periodontal attachment apparatus, whereas direct usage of the protein (rhBMP-2) yields unhinged periodontal relationship. Thus, this approach may represent an alternative means for periodontal alveolar bone graft in clinical settings.

The purpose of this qualitative research study was to explore the preoperative through postoperative phase experience of women who had undergone augmentation mammaplasty. Nine women undergoing augmentation mammaplasty were selected by purposive sampling and interviewed using semi- structured, open-ended interview guidelines. Researchers used Symbolic interactionism to frame their overall perspective and analyzed data with the content analysis method. Rigors of data analysis were adopted credibility, transferability, dependability and confirmability proposed by Guba and Lincoln. The main theme of living experience of women who received augmentation mammaplasty could be summarized as "a journey to restore self-confidence". The categories identified within this journey included: (1) the invisible standards of breast beauty; (2) Taking courageous action to make changes; (3) conflicts between the natural and artificial. The above findings provided initial qualitative data from Taiwanese women's perspective. By better understanding their experience, nurses can become increasingly sensitive to patients' psychosocial adjustment and provide prudential nursing care.

Background Bone grafts, allografts, and biocompatible artificial bone substitutes all have their shortcomings when used for the repair of cranial bone defects. Tissue engineered bone shows promise as an alternative for the repair of these defects. Materials and methods Rabbit bone marrow mesenchymal stromal cells (MSCs) were separated from iliac crest aspirates and expanded in a monolayer culture 1 month before implantation. These MSCs were then infected with replication-defective adenovirus-human BMP-2 genes 1 week before implantation. Bilateral critical-size cranial defects were created in the animal with removal of osteoinductive periosteum and dura. MSCs were mixed with alginate UP (ultrapure) to form MSC/polymer construct. MSCs used for the control site were infected with adenovirus β-galactosidase (β-gal). After 1 week, 6 weeks, and 3 months, five rabbits from each experimental group were sacrificed and the cranial defect site was examined by histology study. Results Near-complete repair of the large size cranial defects using the tissue engineered MSC/alginate construct was observed. The H&E stain and von Kossa’s staining should better regenerate bone at the experiment site. A statistically significant difference in bone formation was noted by 3D CT imaging at 3 months post-BMP-2 treatment of the cranial defects (0.79 ± 0.06 versus 0.47 ± 0.05 cm 2 , P versus 0.33 ± 0.03 cm 2 , P = 0.347). Conclusions Near-complete repair of large cranial defects can be achieved using tissue engineered bone. The use of newly developed polymers as well as the integration of the stem cell concept with gene medicine is necessary to attain this goal.

Each year, more than one million patients undergo some type of procedure involving cartilage reconstruction. Polymer hydrogels such as alginate have been demonstrated to be effective carriers of chondrocytes for subcutaneous cartilage formation. The goal of this study was to develop a simple method to create complex structures with good three-dimensional tolerance in order to form cartilage in specific shapes in an autologous animal model. Six alginate implants that had been seeded with autologous chondrocytes through an injection molding process were implanted subcutaneously in sheep, harvested after 6 months, and analyzed histologically, biochemically, and biomechanically, in comparison with original auricular cartilage. Molds of craniofacial implants were prepared with Silastic E RTV (Dow Corning, Midland, Mich.). Chondrocytes were harvested from sheep auricular cartilage and suspended in 2% alginate at a concentration of 50 x 10(6) cells/ml. The mixture of cells and gel was injected into the Silastic molds and removed after 20 minutes. Chondrocyte-alginate constructs were implanted subcutaneously in the necks of the sheep from which the cells had originally been harvested, and the constructs were removed after 30 weeks. Analyses of the implanted constructs indicated cartilage formation with three-dimensional shape retention. The proteoglycan and collagen contents of the constructs increased with time to approximately 80 percent of the values for native tissue. The equilibrium modulus and the hydraulic permeability were 74 and 105 percent of those of native sheep auricular cartilage, respectively.

Ganglion cysts of the temporomandibular joint are very rare and always misdiagnosed as synovial cyst, parotid gland tumor, or other cystic lesions. They present with pain, swelling, or dysfunction. Image studies could facilitate to identify the tumor mass from the adjacent soft tissue, but a definitive diagnosis could be made from the pathologic report.A 59-year-old woman presented to the clinics with a chief complaint of a painless swelling mass in the right preauricular region of 3-month duration. Computed tomography was performed, which showed a small radiolucent lesion adjacent to the right condyle. Local excision was performed, and the specimen was sent for histologic examination.Microscopic examination showed a cystic space walled by dense fibrous connective tissue without epithelial or endothelial lining. Immunohistochemical staining of these lining cells showed positivity for vimentin and negativity for cytokeratin. These findings were consistent with the diagnosis of ganglion cyst.Ganglion cysts present as unilobulate or multilobulate cysts that arise from the collagenous tissue and is filled with highly viscous fluid. It does not communicate with the joint cavity. In contrast, synovial cyst is a true cyst lined by cuboidal or flattened cells from the synoviocytes and is filled with gelatinous fluid. It may or may not communicate with the joint cavity. Excision is the treatment of choice of symptomatic cystic lesions. Incomplete excision of these lesions may cause further recurrence or infection. Thus, injection of hydrocortisone or aspiration may be considered as an alternative management.

Over one million patients per year undergo some type of procedure involving cartilage reconstruction. Polymer hydrogels, such as alginate, have been shown to be effective carriers for chondrocytes in subcutaneous cartilage formation. The goal of our current study was to develop a method to create complex structures (nose bridge, chin, etc.) with good dimensional tolerance to form cartilage in specific shapes. Molds of facial implants were prepared using Silastic ERTV. Suspensions of chondrocytes in 2% alginate were gelled by mixing with CaSO(4) (0.2 g/mL) and injected into the molds. Constructs of various cell concentrations (10, 25, and 50 million/mL) were implanted in the dorsal aspect of nude mice and harvested at times up to 30 weeks. Analysis of implanted constructs indicated progressive cartilage formation with time. Proteoglycan and collagen constructs increased with time to approximately 60% that of native tissue. Equilibrium modulus likewise increased with time to 15% that of normal tissue, whereas hydraulic permeability decreased to 20 times that of native tissue. Implants seeded with greater concentrations of cells increased proteoglycan content and collagen content and equilibrium and decreased permeability. Production of shaped cartilage implants by this technique presents several advantages, including good dimensional tolerance, high sample-to-sample reproducibility, and high cell viability. This system may be useful in the large-scale production of precisely shaped cartilage implants.

Epistaxis is a frequent finding in patients with facial trauma. Herein, we report an unusual presentation of pediatric naso-orbital-ethmoid (NOE) fracture with epistaxis as the only initial symptom. The course of the patient's condition was later complicated by meningitis, related in part to the delay in diagnosis. A 3-year-old girl with preexisting upper respiratory symptoms was involved in a traffic accident, sustaining blunt trauma to the right side of her face. During the initial examination, only right-sided epistaxis was noted. Five days later, she developed febrile convulsion and was admitted to the intensive care unit with other signs of meningitis such as mental status change and neck stiffness. Her craniofacial computed tomographic scan showed a right-sided NOE fracture with minimal displacement and without dura tear. The cerebrospinal fluid culture grew Streptococcus pneumoniae, which may be due to ascending infection as a result of cribriform plate fracture. Intravenous antibiotic therapy was initiated with good response, and she was discharged from the hospital after 2 weeks. The presence of epistaxis and periorbital bruise, together with other symptoms and signs, helps in the identification of NOE and cribriform plate fracture. A high index of suspicion with repetitive computed tomographic scans is necessary to achieve correct early diagnosis. Parental antibiotic therapy is indicated if ascending cerebrospinal fluid infection develops.

From March of 1995 to November of 1997, 95 free radial forearm flaps for orofacial reconstructions were performed and included in this prospective study of donor site morbidity. All flaps were elevated using the suprafascial dissection technique. Donor site closure was performed with either split-thickness skin grafts (64 cases) or full-thickness skin grafts (31 cases). Among the 95 flaps, there were two complete flap losses and one partial flap loss because of arterial thrombosis. One orocutaneus fistula was successfully treated with a pedicled pectoralis major flap. At the donor site, the rate of complete take of skin graft was 94 percent in 95 patients. Functional and aesthetic results evaluated at least 6 months postoperatively in 50 patients revealed no significant change in grip power, pulp-to-pulp pinch power, or wrist movement in the complete skin graft take group (45 cases), whereas in the partial skin graft failure group (5 cases), both grip power and movement were significantly decreased. There was no remarkable cold intolerance in any of the 50 patients. Critical evaluations of sensory change revealed numbness distal to the donor site in 54 percent of the patients. However, dysesthesia was usually mild and improved spontaneously as time passed. Aesthetic outcome was rated as good or fair in 98 percent of the cases. The results of this prospective study show that suprafascial elevation of the radial forearn flap is superior to the classic elevation technique, particularly with regard to a higher rate of immediate complete take of ski n grafts, thus avoiding impairment of range of motion and strength of the donor hand.

Osteoma is one of most common benign tumors of the nose and paranasal sinuses, with the frontal sinus being its most frequent location. It may be locally destructive and aggressive with possible intracranial complications. Osteoma of the frontal sinus comprises 57% of all osteomas in the paranasal sinuses. In 1939, Childrey reviewed 3,510 consecutive sinus radiographs taken for any reason and found an incidence of 0.43% of paranasal sinus osteomas. There are many operative approaches for frontal sinus osteomas, such as external frontoethmoidal approach and osteoplastic frontal sinusectomy, both with high recurrence rates. Those traditional operative methods cannot radically eradiate the osteoma grown in the posterior table of the frontal sinus. From July 1991 to June 1992, three patients with symptomatic frontal sinus osteomas were operated by a craniofacial approach. One patient is presented here in detail. A coronal incision is used and is found to be beneficial both in surgical exposure and in reconstruction with a calvarial bone graft. The patient has been followed for 3.5 years without osteoma recurrence.

A technique of suprafascial flap elevation to prevent donor site problems is described, based on careful intraoperative observation of the anatomical relations of all involved structures in a series of over 400 free forearm flaps used in various reconstructive procedures.