Postoperative instructions after endoscopic sinus surgery: is there a consensus?

BACKGROUND: Most endoscopic sinus surgeons instruct their patients to avoid certain activities during the postoperative period. Due to the scarcity of empirical data on this issue, most instructions are based on surgeons’ personal insights. In this study we evaluated if restrictions for performing specific activities have a consensus among endoscopic sinus surgeons. METHODOLOGY: A nationwide survey was conducted among experienced Israeli endoscopic sinus surgeons. Participants were asked to note the optimal postoperative time restrictions of 25 different activities. RESULTS: The response rate was 30/36 (83%). Surgeons’ responses regarding time restrictions of specific activities postoperatively showed high variance. The greatest variance was noted for using a hair dryer, light physical activities, nose blowing, driving a car, having sexual intercourse, eating/drinking hot food or beverages, taking hot showers and drinking alcohol. CONCLUSIONS: The time restrictions given by endoscopic sinus surgeons for specific activities postoperatively vary greatly among them. The study findings call upon rhinology boards to establish consensus-based guidelines for postoperative management after endoscopic sinus surgery.

Surgical Management of Hidradenitis Suppurativa: Factors Associated with Postoperative Complications and Disease Recurrence

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disorder. Treatment of HS remains challenging, and surgical procedures commonly follow attempts of conservative therapy. To date, a consensus regarding the optimal surgical technique has not been reached, and the implications of conservative therapy on future surgical outcomes have yet to be studied.

METHODS

A retrospective cohort study of 65 patients surgically treated for HS at a tertiary care center was conducted. Patients' medical records were screened for demographical, clinical, and surgical characteristics. Statistical analysis was conducted to determine associations with postoperative complications and disease recurrence.

RESULTS

Fifty patients (75.8%) were treated with systemic antibiotics before opting for surgical resection. Previous treatment with systemic rifampicin was associated with higher rates of postoperative complications (P = 0.029); however, systemic cephalexin and topical clindamycin were associated with a lower rate of complications (P = 0.007 and 0.040, accordingly). Medical history of smoking and surgical management with split-thickness skin grafts were associated with higher rates of postoperative complications (P = 0.012 and 0.014, accordingly). Patients with a greater number of lesions, and those treated with split-thickness skin graft, had higher rates of disease recurrence (P = 0.0018 and 0.003, accordingly).In a multivariate analysis a greater number of lesions (P = 0.0498) and the use of autologous split-thickness skin graft (P = 0.022) were independently associated with higher rates of disease recurrence.

CONCLUSIONS

Previous conservative medical therapy bears the potential to modulate postoperative outcomes in HS patients, and should be taken into consideration. Despite reports of reliable results with split-thickness skin grafts, we found them to be associated with increased rates of diseases recurrence and postoperative complications.

Comparison of CT and adjusted MRI for evaluating paranasal sinuses surgical key landmarks

Background: Sinus CT is the imaging technique of choice for planning endoscopic sinus surgery (ESS). Although MRI has a better soft tissue demonstration, it is not commonly used for ESS due to suboptimal bone demonstration. We hypothesised that adjustment of certain MRI parameters, would allow better demonstration of bones and enable the surgeon to adequately identify surgical landmarks. Methodology: Twenty patients identified as candidates for ESS underwent CT and adjusted MRI exams of the paranasal sinuses (40 in total). rhinologist and a neuroradiologist independently compared and graded 46 bony structures (23 on each side) in each patient's CT and MRI. Overall, 920 anatomical structures were graded by each observer (1840 structures in total). Statistical analysis included overall and per variable grading distribution for each observer, and overall agreement. Results: MRI images were equal, or superior to CT for assessing paranasal anatomy in 66.8% and 86.4% of structures evaluated by the rhinologist and neuroradiologist, respectively. Overall agreement between observers (77%) was moderate. Conclusion: The rhinologist prefers CT demonstration of bony structures, while the neuroradiologist prefers MRI. Still, with the MRI protocol used in this study, according to both, most bony structures are well demonstrated by MRI.

Abstract 224: Critical variables for automated protein immunodetection using western blot

Reliable immunodetection of proteins is a critical step in the discovery of novel biomarkers. It is often performed manually. The immunodetection protocol consists of multiple steps including blocking of nonspecific binding sites, incubation using primary and secondary antibodies and extensive washing between steps that easily introduce bias and errors. The quality of results depends on multiple subjective and objective factors such as the qualification and technical skills of the personnel performing the assay and the accuracy of temporal and temperature control, especially during the immunodetection step. BlotCycler™, automated western blot processor, use fluidic control system that allows to eliminate the variability associated with immunodetection and to achieve higher sensitivity by optimized washing procedure. We used BlotCycler to analyze critical variables for immunodetection including temperature, incubation time and reagent mixing. Relatively small changes in duration and temperature of incubation significantly affect not only the intensity of signal but also the specificity of antibody interaction with antigen. Automated immunodetection at 4ºC significantly improve the specificity of detection and sensitivity that allows reproducible detection of low expressing proteins. Automated processing using BlotCycler allows optimization and control of critical variables leading to improved reproducibility and specificity of immunodetection and should be routinely used for biomarker candidate discovery and confirmation, reliable protein quantification, primary antibody specificity testing, and optimization of primary and secondary antibodies concentrations.

Citation Format: Alexander Margulis, David P. Chimento, Russ Yukhananov. Critical variables for automated protein immunodetection using western blot [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 224. doi:10.1158/1538-7445.AM2017-224

Strabismus and mental disorders among Israeli adolescents

PURPOSE

To assess the association between strabismus and mental disorders in adolescents.

METHODS

This case-control study included 662,641 Israeli teenagers that underwent medical evaluation by the Israel Defense Force as part of the preconscription assessment between 2005 and 2013. The association between common mental disorders (anxiety disorder, mood disorder, adjustment disorder, and attention deficit hyperactivity disorder [ADHD]) and either uncorrected strabismus or corrected strabismus was examined. The association with strabismus correction was assessed by the differences between the corrected and uncorrected groups.

RESULTS

The mean age at the time of the examination was 17.3 ± 0.53 years, with a male predominance (59%). A total of 1,598 subjects (0.24%) had strabismus. Of those, 952 (60%) underwent successful correction and 646 (40%) did not undergo successful correction. A significant association was found between uncorrected strabismus and anxiety disorders (OR = 1.91; 95% CI = 1.02-3.57; P = 0.047) and between corrected strabismus and ADHD (OR = 2.62; 95% CI = 1.18-5.87; P = 0.03). Strabismus correction (as assessed by comparing the uncorrected and corrected strabismus groups) was not significantly associated with the mental disorders we examined, but a nearly statistically significant association with anxiety disorder was observed (OR = 2.978; 95% CI, 1.013-8.754; P = 0.06).

CONCLUSIONS

The evidence from our cohort suggests that strabismus correction, even in the absence of visual impairment, is not associated with mental disorders examined in this study.

Complications of Post-Burn Tissue Expansion Reconstruction: 9 Years Experience with 42 Pediatric and 26 Adult Patients

BACKGROUND

Burn scar reconstruction is extremely challenging, even for the most proficient reconstructive surgeon. Within the arsenal of tools at the plastic surgeon's disposal, tissue expansion provides an efficient modality for reconstruction despite the reported complication rates.

OBJECTIVES

To critically review our experience with tissue expansion for burn scar reconstruction, comparing particularly the adult and pediatric populations.

METHODS

We conducted a retrospective study of the outcomes of patients who underwent burn scar reconstruction with tissue expansion at Hadassah Medical Center between January 2003 and July 2012. The data included patient age, anatomical site of expansion, number of procedures, and associated complications. The outcomes of the above-mentioned populations were also compared with those in a control group of patients undergoing reconstruction with tissue expansion for indications other than burn scars.

RESULTS

Sixty-seven tissue expansion procedures were carried out in 50 patients, 42 in the pediatric population (< 16 years of age) and 25 in the adult population. Complications were observed in 10 of the 42 pediatric procedures (23.8%) and in 3 of the 25 adult procedures (12%). This difference was found to be statistically significant. When the complication rate for each population was compared to its control group (tissue expansion for indications other than burn scar reconstruction, such as reconstruction for motor vehicle accident scarring, congenital nevi, or vascular malformations), no statistically significant difference was found between them (complication rates 19.8% and 12.5%, respectively). Furthermore, there was no statistically significant difference in complication rates between the different anatomical areas of expansion within both populations undergoing burn scar reconstruction. Most of the complicated cases completed successful reconstruction.

CONCLUSIONS

Tissue expansion is a useful surgical tool in post-burn scar reconstruction, both in the adult and pediatric populations and in all anatomic sites, despite consistently high complication rates, especially in the pediatric population. This complication rate is not higher than in patients undergoing tissue expansion for indications other than burn scar reconstruction.

The role of free tissue transfer in posterior neck reconstruction

Reconstruction of the posterior neck is one of the rarer procedures performed by plastic surgeons; we used free flaps for the closure of defects in this area in six cases over the past 4 years. Six patients were located requiring posterior neck reconstruction between the years 2007 and 2013. Five of these patients required reconstruction due to oncologic resections, while one underwent serial removal of a giant congenital nevus. Five of these reconstructions involved the use of a free anterolateral thigh/vastus lateralis flap, and the sixth received a pre-expanded deep inferior epigastric perforator flap. Satisfactory dorsal neck reconstruction was achieved with the free flap approach: it produced excellent healing, contour and coverage of hardware. There was only one early minor complication, allowing early return to daily activities and continuation of planned oncologic treatment. Free flap reconstruction of the posterior neck area is a safe and relatively rapidly performed procedure that yields good results both functionally and aesthetically. In this article, we review the literature on the options available for reconstruction of the posterior neck, describe our surgical experience in such cases, and suggest an algorithm to guide in choosing the optimal approach for a given patient.

Abstract C42: Development and validation of an IHC-based detection method for studying indoleamine 2,3-dioxygenase 1 (IDO1) expression in human cancers

Indoleamine 2,3-dioxygenase-1 (IDO1) mediates oxidative cleavage of tryptophan, an amino acid essential for cell proliferation and survival. The depletion of tryptophan and the generation of tryptophan metabolites have been demonstrated to be an important regulator of immune function. IDO1 is induced by interferons and TLR agonists and is expressed in a wide variety of human cancers as well as in the tumor-draining lymph nodes. High IDO1 expression is significantly associated with more rapid disease progression and poor prognosis in multiple cancer types. Numerous studies have shown that IDO1 negatively regulates immune functions via several potential cellular mechanisms, which in turn allows tumor escape from host immune surveillance. Therefore, inhibition of IDO1 may have therapeutic potential in cancer and IDO1 expression may serve as a selective marker of a responsive population. INCB024360, a novel IDO1-selective inhibitor, is currently being evaluated in clinical trials of cancer patients. To support the clinical development of INCB024360, we have developed and validated an immunohistochemistry (IHC)-based method using rabbit polyclonal antisera that specifically detects IDO1 protein expression. The method has been used to determine IDO1 expression in primary biopsies from patients studied in INCB024360 clinical trials. The method can be used to determine the prevalence of IDO1 expression in a variety of human cancers, identify histologic subtypes that might be associated with IDO1 expression and examine IDO1 coexpression with other immune modifying pathways.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):C42.

Citation Format: Xiangdong Liu, Gengjie Yang, Alexander Margulis, Rich Wynn, Peggy Scherle, Robert Newton. Development and validation of an IHC-based detection method for studying indoleamine 2,3-dioxygenase 1 (IDO1) expression in human cancers. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr C42.

Changes of PI3K/AKT/BCL2 signaling proteins in congenital Giant Nevi: melanocytes contribute to their increased survival and integrity

Congenital Giant Nevi (CGN) are rare melanocytic lesions with the potential to regress into malignant melanoma. Simultaneous up-regulation and cooperative interactions of signaling pathways are crucial events in the pathogenesis of melanocytes. Our study aimed to identify changes in the expression and activation of proteins controlling survival and/or apoptosis of the key signaling pathways PI3K/AKT/BCL2 and Wnt/β-catenin of CGN melanocytes. We applied a model of cultured melanocytes from paired CGN and normal appearing skin, and Western blot (WB) analyzed the expression and activation profile of survival and anti-apoptotic proteins of these signaling pathways, growth pattern, cell cycle and apoptosis. WB analysis demonstrated a significant higher expression level of activated AKT and of BCL2 proteins in the CGN melanocytes compared with paired melanocytes from normal appearing skin. A relative increase in the level of GSK3 and FOXO1 proteins, down stream targets of AKT, as well as of pβ-catenin was also detected in the CGN melanocytes compared with the controls. These changes were not affected by growth of the CGN melanocytes in reduced serum (starvation). Both cell populations shared a similar growth pattern, with no significant differences in the proportion of apoptotic cells and in cell cycle fractions. These data demonstrate for the first time, changes in signaling proteins of cultured CGN melanocytes. Further, suggesting that the changes in AKT/BCL2 signaling molecules might mediate growth and anti-apoptosis processes at least in part, thus increasing the survival potential of CGN melanocytes and maintaining their integrity.

Dorsal augmentation with diced cartilage enclosed with temporal fascia in secondary endonasal rhinoplasty

BACKGROUND

Placement of diced cartilage enclosed within an autologous fascia sleeve (DC-F) for nasal dorsum reconstruction is common in open rhinoplasty, but there are no data regarding its use in closed rhinoplasty (the endonasal approach).

OBJECTIVES

The authors describe a technique for augmenting the nasal dorsum in secondary rhinoplasty with DC-F grafts via an endonasal approach.

METHODS

In this study, the authors retrospectively review the cases of 18 patients who underwent closed rhinoplasty with the authors' technique between 2008 and 2011. Cartilage harvested from the septum, rib, or concha was diced into 0.5- to 1-mm cubes. A rectangle of deep temporal fascia (approximately 5 × 5 cm) was harvested by means of a single V-shaped incision overlying the temporal fossa, then wrapped around another 1-mL syringe and secured. The fascial cylinder was filled with the desired amount of diced cartilage and then sutured closed at both ends. This graft was placed into the dorsum of the nose via the endonasal approach.

RESULTS

Average age of the patients was 32 years. The patients were followed for a minimum of 15 months. Donor site for cartilage harvest was conchal in 8 patients, septal and conchal in 6 cases, and costal in 4. Complications were encountered in 3 patients, only 1 of whom required surgical revision for contour irregularity. No resorption of cartilage was encountered in any patient after 15 months. Smooth continuity of the nasal dorsum was achieved in all our patients.

CONCLUSIONS

Despite the lack of a large volume of patients for overwhelming and conclusive results, our study provides further confirmation that this technique is indeed an attractive option for nasal dorsum reconstruction.

Occurrence and characteristics of head cysts in children

BACKGROUND

Lumps arising in the head and neck constitute an important diagnostic category in children. As malignancy in this age group is relatively rare, lumps that are not due to inflammatory or infective causes often prove to be cysts. Correct diagnoses of the different subcutaneous lumps are often missed because of the lack of recognition or uncertainty with management.

OBJECTIVES

The purpose of this study was to review the characteristics of most common pediatric cysts appearing in the head.

METHODS

A retrospective study was designed to review all the children treated for a cyst in the head during the 12-year period from 1995 to 2007. Study patients had a preoperative diagnosis of a cyst in the head, were younger than 11 years at the time of the diagnosis, and had received a surgical treatment for the condition. The pathological specimens were revised with an expert dermatopathologist, and the clinical data were statistically analyzed.

RESULTS

Of the 90 cysts, 53 were dermoid cysts (58.88%), 16 were diagnosed as pilomatrixomas (17.77%), 5 cysts were diagnosed as branchial cysts (5.55%), and 12 were diagnosed as epidermal cyst (13.33%). Male gender and younger age were significantly associated with correct diagnosis of dermoid cysts (P <.05).

CONCLUSIONS

Ninety-five percent of the cysts fell in 1 of the 4 following categories: dermoid cyst, pilomatrixoma, epidermal cyst, and branchial arch cyst. Dermoid cysts were the most common facial cysts (60%). Correct preoperative diagnosis was more accurate in cases of dermoid and branchial cysts.

Phosphorylation State-Dependent High Throughput Screening of the c-Met Kinase

High-throughput screening (HTS) of ~50,000 chemical compounds against phosphorylated and unphosphorylated c-Met, a tyrosine kinase receptor for hepatocyte growth factor (HGF), was carried out in order to compare hit rates, hit potencies and also to explore scaffolds that might serve as potential leads targeting only the unphosphorylated form of the enzyme. The hit rate and potency for the confirmed hit molecules were higher for the unphosphoryalted form of c-Met. While the target of small molecule inhibitor discovery efforts has traditionally been the phosphorylated form, there are now examples of small molecules that target unphosphorylated kinases. Screening for inhibitors of unphosphorylated kinases may represent a complementary approach for prioritizing chemical scaffolds for hit-to-lead follow ups.

Abstract C165: Determining whether CD52 regulates homotypic cellular aggregation of human B-cells

Human CD52 is a 12 amino acid, GPI-anchored cell surface glycoprotein that is expressed at very high levels on the surface of B-cells, T-cells, monocytes, and macrophages. It is a target for the Campath-1H (alemtuzumab) monoclonal antibody (mAb) that is approved for the treatment of B-cell chronic lymphocytic leukemia. Although some studies have suggested that CD52 plays a role in regulating B-cell signaling and survival, and in preventing cell aggregation, amongst other possibilities, the biological significance of CD52 remains poorly understood. The goal of this study is to further explore the potential role of CD52 in regulating cell aggregation, as it may expand our understanding of the use of anti-CD52 agents in the clinic. Towards this end, CD52 function was disrupted in several transformed CD52-positive human B-cell lines derived from a variety of hematologic malignancies, utilizing α-CD52 mAbs and F(ab)′2 fragments as blocking agents, or CD52 shRNAs to knockdown expression. A high-throughput quantitative aggregation assay was developed in-house that measures both the number and size of single cells as well as aggregates that can be classified as small (2–5 cells), medium (∼6–100 cells), and large cell clusters (&gt;100 cells). We have observed enhanced formation of tightly adherent clusters following the exposure of the BL31, DND39, Raji, and numerous other B-cell lines with Campath and several other -CD52 mAbs relative to isotype controls. Cell viability was also measured in these experiments and shown not to be substantially affected by exposure to these mAbs. To rule out Fc R (CD32) crosslinking as a potential mechanism for this effect, we have utilized two approaches. First, the Campath F(ab)′2 fragment was also used, and was shown to increase cellular aggregation. Second, we have determined which of these cell lines express CD32, established the appropriate concentration of an -CD32 mAb required for sufficient Fc R blocking, and have shown that aggregation was not disrupted by this -CD32 blocking mAb in -CD52 mAb-treated cells. Using shRNAs targeting two different sequences in the CD52 mRNA, we were able to significantly knockdown CD52 surface levels and generate dozens of low-expressing clones with either of these CD52 shRNAs, or high expressing clones with an shRNA negative control plasmid, from three of the aforementioned B-cell lines. Greater cell aggregation was observed in CD52 knockdown clones derived from BL31 and Raji relative to shRNA negative control clones when cultured in growth media. While we observed only moderate increases in the aggregation of some DND39 knockdown clones under these same conditions, when these clones were stimulated with an α-IgM antibody, CD52 knockdown significantly augmented their aggregation. Taken together, the results generated using these two complementary approaches provide strong evidence for a role of CD52 in negative regulation of B-cell aggregation. Additional studies are underway to better understand these observations.

Citation Information: Mol Cancer Ther 2009;8(12 Suppl):C165.

IL-33 synergizes with IgE-dependent and IgE-independent agents to promote mast cell and basophil activation

OBJECTIVE

Mast cell and basophil activation contributes to inflammation, bronchoconstriction, and airway hyperresponsiveness in asthma. Because IL-33 expression is inflammation inducible, we investigated IL-33-mediated effects in concert with both IgE-mediated and IgE-independent stimulation.

METHODS

Because the HMC-1 mast cell line can be activated by GPCR and RTK signaling, we studied the effects of IL-33 on these pathways. The IL-33- and SCF-stimulated HMC-1 cells were co-cultured with human lung fibroblasts and airway smooth muscle cells in a collagen gel contraction assay. IL-33 effects on IgE-mediated activation were studied in primary mast cells and basophils.

RESULT

IL-33 synergized with adenosine, C5a, SCF, and NGF receptor activation. IL-33-stimulated and SCF-stimulated HMC-1 cells demonstrated enhanced collagen gel contraction when cultured with fibroblasts or smooth muscle cells. IL-33 also synergized with IgE receptor activation of primary human mast cells and basophils.

CONCLUSION

IL-33 amplifies inflammation in both IgE-independent and IgE-dependent responses.

Transport distraction osteogenesis for closing full-thickness calvarial defects in sheep

OBJECTIVE

To prove the hypothesis that transport distraction osteogenesis can be applied to the skull to close critical-size calvarial defects.

DESIGN

A sheep model was developed to investigate this hypothesis. In four sheep, bilateral parietal bone windows were created and adjacent osteotomies performed. On the tested side, an adjacent bone segment was transported into the defect. The contralateral side was left untreated as a control.

MAIN OUTCOME MEASURES

After completion of the distraction and consolidation period, a computed tomography study was performed, and the animals were sacrificed. The newly formed bone was examined macroscopically and histologically.

RESULTS

A successful closure of the defect with transport distraction was achieved in all of the animals. The control side healed spontaneously in one (younger) sheep but did not heal in the other three animals. The closure of the bony defect with transport distraction was evident macroscopically as well as on the computerized tomography. Microscopic examination showed new healthy bone formation on the treated side.

CONCLUSION

We conclude that transport distraction is an effective tool in closing full-thickness calvarial defects in adult sheep. Further investigation is needed before applying this promising technique in humans.

Pediatric tissue expansion: our experience with 103 expanded flap reconstructive procedures in 41 children

BACKGROUND

Tissue expansion is a well-recognized technique for reconstructing a wide variety of skin and soft tissue defects. Its application in the pediatric population has enabled the plastic surgeon to achieve functional and aesthetic goals that were previously unobtainable.

OBJECTIVES

To review the use of tissue expansion in the pediatric population, with particular emphasis on indication, operative technique, regional considerations and how to avoid complications.

METHODS

We retrospectively reviewed data on 103 expanded flap reconstructions performed in 41 pediatric patients during the period 2003-2006. Tissue expanders were placed on a subcutaneous plane above the fascia and inflated weekly. The expanded skin was used as a transposition flap or a full thickness skin graft for the reconstruction of the involved area. Forty-three tissue expanders were inserted to the head and neck in 21 patients, 45 were inserted to the trunk in 13 patients and 15 were inserted to the groin and lower extremity in 8 patients. Twenty-eight patients had one round of tissue expansion, while 13 patients had two to six rounds. A plastic surgeon, medical student and a lawyer reviewed the patients' photographs and evaluated their aesthetic outcome:

RESULTS

Eighty-six percent of the head and neck reconstructions and 40% of the trunk and extremity reconstructions were graded as having excellent aesthetic outcome, and 11% of the head and neck reconstructions and 37% of the trunk and extremity reconstructions were graded with good aesthetic outcome. The remaining patients were graded with moderate outcome. None of our patients was graded as poor aesthetic outcome. Complications included infection in 6 patients (6%), extrusion in 3 (3%), hematoma in 2 (2%), flap ischemia in one patient (1%), and expander perforation after percutaneous stabbing in one patient (1%).

CONCLUSIONS

Tissue expansion is an efficient and valuable technique for reconstruction of large skin lesions and scars.

Mast cell-dependent contraction of human airway smooth muscle cell-containing collagen gels: influence of cytokines, matrix metalloproteases, and serine proteases

In asthma, mast cells infiltrate the airway smooth muscle cell layer and secrete proinflammatory and profibrotic agents that contribute to airway remodeling. To study the effects of mast cell activation on smooth muscle cell-dependent matrix contraction, we developed coculture systems of human airway smooth muscle cells (HASM) with primary human mast cells derived from circulating progenitors or with the HMC-1 human mast cell line. Activation of primary human mast cells by IgE receptor cross-linking or activation of HMC-1 cells with C5a stimulated contraction of HASM-embedded collagen gels. Contractile activity could be transferred with conditioned medium from activated mast cells, implicating involvement of soluble factors. Cytokines and proteases are among the agents released by activated mast cells that may promote a contractile response. Both IL-13 and IL-6 enhanced contraction in this model and the activity of IL-13 was ablated under conditions leading to expression of the inhibitory receptor IL-13Ralpha2 on HASM. In addition to cytokines, matrix metalloproteinases (MMPs), and serine proteases induced matrix contraction. Inhibitor studies suggested that, although IL-13 could contribute to contraction driven by mast cell activation, MMPs were critical mediators of the response. Both MMP-1 and MMP-2 were strongly expressed in this system. Serine proteases also contributed to contraction induced by mast cell-activating agents and IL-13, most likely by mediating the proteolytic activation of MMPs. Hypercontractility is a hallmark of smooth muscle cells in the asthmatic lung. Our findings define novel mechanisms whereby mast cells may modulate HASM-driven contractile responses.

Combination of preoperative embolization and surgery in the treatment of a giant congenital neuroid nevus of the forehead and scalp in a child. Case report

Congenital melanocytic nevi of neuroectodermal origin are composed primarily of melanocytes and occasional neural elements. A subset of large/giant congenital melanocytic nevi is characterized by neuroidal differentiation resembling the histological pattern of neurofibroma (neuroid congenital melanocytic nevi). The authors report the case of a male infant born with a neuroid congenital melanocytic nevus presenting as a large mass covering extensive portions of his scalp and forehead. The atypical feeding arteries to the nevus were larger in diameter then the patient's internal carotid arteries and formed a rich network of large blood vessels in the nevus. Selective preoperative embolization using calibrated particles was followed by a complete excision and staged reconstruction with tissue expanders. The authors believe that this multidisciplinary approach allowed for a safe surgical procedure with minimal blood loss for this most unusual pediatric head and neck tumor.

MMP dependence of fibroblast contraction and collagen production induced by human mast cell activation in a three-dimensional collagen lattice

Mast cell-fibroblast interactions may contribute to fibrosis in asthma and other disease states. Fibroblast contraction is known to be stimulated by coculture with the human mast cell line, HMC-1, or by mast cell-derived agents. Matrix metalloproteinases (MMPs) can also mediate contraction, but the MMP-dependence of mast cell-induced fibroblast contractility is not established, and the consequences of mast cell activation within the coculture system have not been fully explored. We demonstrate that activation of primary human mast cells (pHMC) with IgE receptor cross-linking, or activation of HMC-1 with C5a, enhanced contractility of human lung fibroblasts in a three-dimensional collagen lattice system. This enhanced contractility was inhibited by the pan-MMP antagonist, batimastat, and was transferrable in the conditioned medium of activated mast cells. Exogenously added MMPs promoted gel contraction by mediating the proteolytic activation of latent transforming growth factor-beta (TGF-beta). Consistent with this, fibroblast contraction induced by mast cell activation was enhanced by addition of excess latent TGF-beta to the cultures. Batimastat inhibited this response, suggesting that MMPs capable of activating latent TGF-beta were released following mast cell activation in coculture with fibroblasts. Collagen production was also stimulated by activated mast cells in an MMP-dependent manner. MMP-2 and MMP-3 content of the gels increased in the presence of activated mast cells, and inhibition of these enzymes blocked the contractile response. These findings demonstrate the MMP dependence of mast cell-induced fibroblast contraction and collagen production.

Superficial zone chondrocytes in normal and osteoarthritic human articular cartilages synthesize novel truncated forms of inter-alpha-trypsin inhibitor heavy chains which are attached to a chondroitin sulfate proteoglycan other than bikunin

OBJECTIVE

We have examined the occurrence of the inflammation-associated inter-alpha-trypsin inhibitor (IalphaI) components, bikunin, heavy chain (HC)1 and HC2 in normal cartilage and osteoarthritis (OA) cartilage and synovial fluids.

DESIGN/METHODS

Cartilage extracts from normal donors and late-stage OA patients, and synovial fluids from OA patients were studied by Western blot with multiple antibodies to bikunin, HC1 and HC2. Cell and matrix localization was determined by immunohistochemistry and mRNA by RT-PCR.

RESULTS

Bikunin.chondroitin sulfate (CS) and IalphaI were abundant in OA cartilages, but virtually undetectable in normal. In both OA and normal cartilages, HCs were largely present in a novel C-terminally truncated 50-kDa form, with most, if not all of these being attached to CS on a proteoglycan other than bikunin. Synovial fluids from OA patients contained bikunin.CS and full-length (approximately 90 kDa) HCs linked to hyaluronan (HA) as HC.HA (SHAP.HA). Immunohistochemistry showed intracellular and cell-associated staining for bikunin and HCs, consistent with their synthesis by superficial zone chondrocytes. PCR on multiple human normal and OA cartilage samples detected transcripts for HC1 and HC2 but not for bikunin. In OA cartilages, immunostaining was predominantly matrix-associated, being most intense in regions with a pannus-like fibrotic overgrowth.

CONCLUSION

The truncated structure of HCs, their attachment to a proteoglycan other than bikunin, PCR data and intracellular staining are all consistent with synthesis of HC1 and HC2 by human articular chondrocytes. The presence of bikunin.CS and IalphaI in OA cartilage, but not in normal, appears to be due to diffusional uptake and retention through fibrillated (but not deeply fissured) cartilage surfaces.

The Expanded Supraclavicular Flap, Prefabricated with Thoracoacromial Vessels, for Reconstruction of Postburn Anterior Cervical Contractures

Mentosternal contractures are well-known complications after burns, scald injuries, and injuries with acid or lye. These contractures may cause severe deformities that are both functionally and aesthetically crippling. Reconstruction of the neck requires the transfer of large flaps of thin, pliable skin to optimally match the texture and color of the recipient region. With the introduction of free tissue transfer, the availability of flaps for reconstruction of large neck defects has greatly increased. Unfortunately, many of these flaps are bulky and are not well matched to the thin and pliable skin of the neck. This article introduces the expanded supraclavicular flap prefabricated with the thoracoacromial vessels for reconstruction of anterior cervical contractures. Their anatomic location, length, and arc of rotation make the thoracoacromial vessels an excellent choice for prefabricating the supraclavicular skin for its subsequent interpolation into the anterior neck. Skin expansion in the donor region not only allows coverage of the larger unit of the anterior neck but also modifies the morphologic characteristics of the transferred flap through capsule formation and fatty tissue atrophy, which is beneficial for obtaining an optimal neck reconstruction.

High-throughput determination of mode of inhibition in lead identification and optimization

After finishing the primary high-throughput screening, the screening team is often faced with thousands of hits to be evaluated further. Effective filtering of these hits is crucial in identifying leads. Mode of inhibition (MOI) study is extremely useful in validating whether the observed compound activity is specific to the biological target. In this article, the authors describe a high-throughput MOI determination method for evaluating thousands of compounds using an existing screening infrastructure. Based on enzyme or receptor kinetics theory, the authors developed the method by measuring the ratio of IC(50) or percent inhibition at 2 carefully chosen substrate or ligand concentrations to define an inhibitor as competitive, uncompetitive, or noncompetitive. This not only facilitates binning of HTS hits according to their MOI but also greatly expands HTS utility in support of the medicinal chemistry team's lead optimization practice. Three case studies are presented to demonstrate how the method was applied successfully in 3 discovery programs targeting either an enzyme or a G-protein-coupled receptor.

Management of severe tip ptosis in closed rhinoplasty: the horizontal columellar strut

BACKGROUND

Tip ptosis is a relatively common nasal deformity, with an incidence as high as 72% in rhinoplasty patients. Different techniques were described for surgical correction of the droopy tip, such as the lateral crural steel, the lateral crural overlay, the tongue-in-groove technique and others. Most authors agreed that an external rhinoplasty approach is necessary for effectively conducting the alar cartilage-modifying techniques mentioned above.

METHODS

In this article we challenge this paradigm and introduce an efficient method for aesthetic correction of severe tip ptosis through an internal rhinoplasty approach. Twenty-three patients with severe ptosis of the nasal tip were operated on by the senior author (MH) between 2000 and 2005 using the described technique. After carrying out the necessary manoeuvres to achieve the desired tip rotation (reduction of cephalic border of alar cartilages, modification of the caudal septum, reduction of upper lateral cartilages), the desired tip position was maintained with the horizontal columellar strut, whose initial operative description appears here.

RESULTS

The desired rotation and projection were maintained in all but three patients over the first year after the surgery. In three patients we observed some loss of tip projection after 1 year. We did not witness complications directly related to the horizontal columellar strut.

CONCLUSION

The horizontal columellar strut is an efficient tool for stabilising the corrected position of a severely ptotic nasal tip. We recommend adding the horizontal columellar strut to the array of available rhinoplasty techniques.

[Ankle chondrocytes are more resistant to Interleukin-1 than chondrocytes derived from the knee]

BACKGROUND

The incidence of degenerative changes and osteoarthritis is lower in the ankle than in the knee joints. This cannot be explained exclusively with differences in anatomy and biomechanical properties of these two synovial joints. Previous studies have indicated distinct differences in the biochemical composition of the extracellular matrix of articular cartilage from knee and ankle joints. The aim of this study was to identify potential metabolic differences between knee and ankle joint chondrocytes using isolated cells to distinguish the secondary effects of the resident extracellular matrix from the primary matrix-independent effects of cellular differentiation.

METHOD

Isolated knee and ankle chondrocytes from the same human donor were cultured in alginate beads and subsequently exposed to a three-day pulse of the catabolic cytokine interleukin-1 (IL-1) as a model of an inflammatory episode. The metabolism of proteoglycans (PG's) was analyzed as expressed changes in 35S-sulfate incorporation into glycosaminoglycans (GAG's).

RESULTS

The presence of IL-1 induced an inhibition of PG synthesis in knee and ankle articular chondrocytes. The 50% inhibitory concentration (IC50) of IL-1 was about 5 times lower for knee than for ankle chondrocytes.

CONCLUSION

Ankle chondrocytes are more resistant to IL-1 induced inhibition of PG synthesis than chondrocytes from the knee.

Reconstruction of pectus excavatum with silicone implants

The pectus excavatum deformity is characterised by a deep depression usually involving the lower one-half to two-thirds of the sternum. The indications for surgery are often aesthetic. Extensive procedures, requiring fracturing and remodelling of the chest wall skeleton are associated with high morbidity and high rate of complications. In this article we describe our renewed experience with reconstruction of mild and moderate pectus excavatum deformities with custom made prefabricated silicone implants. The fabrication of the implant and the surgical technique are described in detail. An excellent aesthetic correction of the deformity was achieved in all of the patients in our series, with high patient satisfaction rate. We conclude that with careful patient selection, artistic implant fabrication and meticulous surgical technique, this approach achieves excellent aesthetic correction with minimal morbidity and a low complication rate and therefore should maintain its place in the armamentarium of surgical techniques for reconstruction of pectus deformities.

[Clinical and genetic study in 22 patients with basal cell nevus syndrome]

BACKGROUND

Nevoid basal cell carcinoma syndrome is an autosomal dominant disorder characterized by developmental abnormalities and cancer predisposition. The PTCH 1 gene, the human homolog of the Drosophila segment polarity gene patched, has been shown to be involved in the development of nevoid basal cell carcinoma syndrome. PTCH 1 is mapped to chromosome 9q22.3. The aim of the present study was to report on clinical and genetic characteristics in patients followed for nevoid basal cell carcinoma syndrome and to compare them to the data in the literature.

PATIENTS AND METHODS

Screening for PTCH 1 mutations was done in 22 patients followed between 1981 and 2003 for clinical suspicion of nevoid basal cell carcinoma syndrome. Clinical and radiological data were reviewed retrospectively from records. Genetic analysis was performed using blood samples after patient informed consent was obtained. When possible, DNA was also analyzed from the parents of patients in whom PTCH 1 mutations were found.

RESULTS

All patients had developed basal cell carcinomas: 45% palmar and plantar pitting, 62% jaw cysts and 66% calcification of falx cerebri. Medulloblastomas and meningiomas were the most common associated tumors. PTCH 1 mutations were identified in 13 patients: 6 familial cases, 3 sporadic cases and for 4 patients, it was not possible to conclude. Nine different new germ-line mutations were identified.

DISCUSSION

Genetic analysis allows molecular confirmation of diagnosis in about half of all patients. Early diagnosis is essential for detection of clinical and radiological manifestations in young patients and for provision of advice concerning protection of the skin from the sunlight.

Microcystic Adnexal Carcinoma: Report of Seven Cases Including One with Lung Metastasis

BACKGROUND

Microcystic adnexal carcinoma (MAC) is a rare cutaneous neoplasm, with a high rate of local recurrences.

OBJECTIVE

A series of MAC was analyzed and compared to previously published cases.

METHODS

Seven cases of MAC were identified in the register of the institution. Medical and pathological records were reviewed.

RESULTS

The primary MAC were located on the face in all patients, and 85% were initially misdiagnosed. The mean follow-up duration was 108 months. The recurrence rate was high: 4 patients developed recurrences. In 3 patients, the course of the disease was severe: one of them developed pathologically proven lung metastasis.

CONCLUSION

The present study and review of the literature confirm the clinically aggressive evolution of MAC and its rare ability to give rise to metastasis. Long-term clinical follow-ups with imaging investigations are mandatory.

E-cadherin loss promotes the initiation of squamous cell carcinoma invasion through modulation of integrin-mediated adhesion

Much remains to be learned about how cell-cell and cell-matrix interactions are coordinated to influence the earliest development of neoplasia. We used novel 3D human tissue reconstructs that mimic premalignant disease in normal epidermis, to directly investigate how loss of E-cadherin function directs conversion to malignant disease. We used a genetically tagged variant of Ha-Ras-transformed human keratinocytes (II-4) expressing dominant-interfering E-cadherin fusion protein (H-2kd-Ecad). These cells were admixed with normal human keratinocytes and tumor cell fate was monitored in 3D reconstructed epidermis upon transplantation to immunodeficient mice. Tumor initiation was suppressed in tissues harboring control- and mock-infected II-4 cells that lost contact with the stromal interface. By contrast, H-2kd-Ecad-expressing cells persisted at this interface, thus enabling incipient tumor cell invasion upon in vivo transplantation. Loss of intercellular adhesion was linked to elevated cell surface expression of α2, α3 and β1 integrins and increased adhesion to laminin-1 and Types I and IV collagen that was blocked with β1-integrin antibodies, suggesting that invasion was linked to initial II-4 cell attachment at the stromal interface. Collectively, these results outline a novel aspect to loss of E-cadherin function that is linked to the mutually interdependent regulation of cell-cell and cell-matrix adhesion and has significant consequences for the conversion of premalignancy to cancer.

Loss of intercellular adhesion activates a transition from low- to high-grade human squamous cell carcinoma

The relationship between loss of intercellular adhesion and the biologic properties of human squamous cell carcinoma is not well understood. We investigated how abrogation of E-cadherin-mediated adhesion influenced the behavior and phenotype of squamous cell carcinoma in 3D human tissues. Cell-cell adhesion was disrupted in early-stage epithelial tumor cells (HaCaT-II-4) through expression of a dominant-negative form of E-cadherin (H-2Kd-Ecad). Three-dimensional human tissue constructs harboring either H-2Kd-Ecad-expressing or control II-4 cells (pBabe, H-2Kd-EcadDeltaC25) were cultured at an air-liquid interface for 8 days and transplanted to nude mice; tumor phenotype was analyzed 2 days and 2 and 4 weeks later. H-2Kd-Ecad-expressing tumors demonstrated a switch to a high-grade aggressive tumor phenotype characterized by poorly differentiated tumor cells that infiltrated throughout the stroma. This high-grade carcinoma revealed elevated cell proliferation in a random pattern, loss of keratin 1 and diffuse deposition of laminin 5 gamma2 chain. When II-4 cell variants were seeded into type I collagen gels as an in vitro assay for cell migration, we found that only E-cadherin-deficient cells detached, migrated as single cells and expressed N-cadherin. Function-blocking studies demonstrated that this migration was matrix metalloproteinase-dependent, as GM-6001 and TIMP-2, but not TIMP-1, could block migration. Gene expression profiles revealed that E-cadherin-deficient II-4 cells demonstrated increased expression of proteases and cell-cell and cell-matrix proteins. These findings showed that loss of E-cadherin-mediated adhesion plays a causal role in the transition from low- to high-grade squamous cell carcinomas and that the absence of E-cadherin is an important prognostic marker in the progression of this disease.

Microenvironmental control of premalignant disease: the role of intercellular adhesion in the progression of squamous cell carcinoma

Interactions between potentially neoplastic cells and their normal neighbors act as an important microenvironmental control during the premalignant, intraepithelial (IE) stage of squamous cell cancer development. Using human three-dimensional (3D) tissue models, it has been shown that such interactions induce a state of IE dormancy in which cancer progression is suppressed. This dormant state can be overcome by altering tissue dynamics in response to the tumor promoter TPA, UV irradiation, decreasing adhesive interactions between tumor cells and adjacent epithelia or enabling tumor cells to interact with basement membrane proteins. This chapter will provide an overview of investigations that have characterized how the tissue microenvironment can regulate the incipient development of squamous cell carcinoma.

E-cadherin suppression accelerates squamous cell carcinoma progression in three-dimensional, human tissue constructs

We studied the link between loss of E-cadherin-mediated adhesion and acquisition of malignant properties in three-dimensional, human tissue constructs that mimicked the initial stages of squamous cell cancer progression. Suppression of E-cadherin expression in early-stage, skin-derived tumor cells (HaCaT-II-4) was induced by cytoplasmic sequestration of beta-catenin upon stable expression of a dominant-negative E-cadherin fusion protein (H-2Kd-Ecad). In monolayer cultures, expression of H-2Kd-Ecad resulted in decreased levels of E-cadherin, redistribution of beta-catenin to the cytoplasm, and complete loss of intercellular adhesion when compared with control II-4 cells. This was accompanied by a 7-fold decrease in beta-catenin-mediated transcription and a 12-fold increase in cell migration. In three-dimensional constructs, E-cadherin-deficient tissues showed disruption of architecture, loss of adherens junctional proteins from cell contacts, and focal tumor cell invasion. Invasion was linked to activation of matrix metalloproteinase (MMP)-mediated degradation of basement membrane in H-2Kd-Ecad-expressing tissue constructs that was blocked by MMP inhibition (GM6001). Quantitative reverse transcription-PCR showed a 2.5-fold increase in MMP-2 and an 8-fold increase in MMP-9 in cells expressing the H-2Kd-Ecad fusion protein when compared with controls, and gel zymography showed increased MMP protein levels. Following surface transplantation of three-dimensional tissues, suppression of E-cadherin expression greatly accelerated tumorigenesis in vivo by inducing a switch to high-grade carcinomas that resulted in a 5-fold increase in tumor size after 4 weeks. Suppression of E-cadherin expression and loss of its function fundamentally modified squamous cell carcinoma progression by activating a highly invasive, aggressive tumor phenotype, whereas maintenance of E-cadherin prevented invasion in vitro and limited tumor progression in vivo.

In vivo transplantation of engineered human skin

Tissue engineering approaches have enabled the development of methodologies that allow long-term, in vivo studies in epidermal biology. This has been accomplished through in vivo transplantation of human epidermal cells fabricated as three-dimensional, skin-equivalents in vitro. The methodologies presented in this chapter describe how skin-equivalent (organotypic) cultures are transplanted to nude mice to generate human skin grafts that normalize their tissue architecture, basement membrane structure and barrier function shortly after grafting. By grafting skin equivalents as composite cultures featuring well-differentiated human epidermis and fibroblasts in collagen gel, transplants are "primed" for accelerated take of grafted tissues. The methods outlined can generate stable, human epidermis that mimics the in vivo tissue.

In vitro fabrication of engineered human skin

In vitro fabrication of human epidermal tissues that mimic the biochemical and morphologic properties of human skin, known as skin-equivalent (organotypic) cultures, has opened new avenues in the study of skin biology. In this chapter, methods for the generation of these tissues from their component parts are described. Conditions for culture of human keratinocytes and fibroblasts that allow optimal growth in skin equivalent cultures are delineated. These cell types are then sequentially combined so that keratinocytes are grown at an air-liquid interface on a contracted collagen gel containing dermal fibroblasts. The methods described enable the generation of human epidermal tissues that show in vivo-like tissue architecture and phenotype.

The importance of conchal resection in correcting the prominent ear

The authors believe that conchal hypertrophy plays a more significant role in ear prominence than has been indicated in the literature. Instead of focusing on the antihelical fold, this otoplasty technique emphasizes chondrocutaneous resection. With even limited resection and resuturing of the cut concha, the antihelix yields to posterior suture placement with a soft, smooth, rounded shape unmarred by any sharp, irregular surfaces.

The central acidic domain of MDM2 is critical in inhibition of retinoblastoma-mediated suppression of E2F and cell growth

Retinoblastoma (Rb) protein is a paradigm of tumor suppressors. Inactivation of Rb plays a critical role in the development of human malignancies. MDM2, an oncogene frequently found amplified and overexpressed in a variety of human tumors and cancers, directly interacts and inhibits the p53 tumor suppressor protein. In addition, MDM2 has been shown to stimulate E2F transactivation activity and promote S-phase entry independent of p53, yet the mechanism of which is still not fully understood. In this study, we demonstrate that MDM2 specifically binds to Rb C-pocket and that the central acidic domain of MDM2 is essential for Rb interaction. In addition, we show that overexpression of MDM2 reduces Rb-E2F complexes in vivo. Moreover, the ectopic expression of the wild type MDM2, but not mutant MDM2 defective in Rb interaction, stimulates E2F transactivation activity and inhibits Rb growth suppression function. Taken together, these results suggest that MDM2-mediated inhibition of Rb likely contributes to MDM2 oncogenic activity.

The Expanded Transposition Flap: Shifting Paradigms Based on Experience Gained from Two Decades of Pediatric Tissue Expansion

The authors present their experience with the design of expanded skin flaps gained over the past two decades in a large series of 995 expanded flap reconstructions performed in 626 operations in 430 patients. The indications for tissue expansion were giant congenital pigmented nevi (72.7 percent), scar contractures (11.2 percent), and a remainder for a variety of congenital and acquired deformities. Surgical strategies were reviewed retrospectively to determine the location in the body where the tissue expansion was performed, the number of procedures required to accomplish the reconstructive goal, and the design of the expanded flap that was used to reconstruct the involved area. Specific points that were noticed included contour deformities (such as webbing, dog-ears, or decreased limb circumference) following flap reconstruction, anatomic distortions (such as distortion of the eyebrow or the distance from the brow to hairline) following reconstruction, final position of the scars in relation to anatomic landmarks, borders of aesthetic units, and relaxed skin tension lines, and the potential for later scar contracture. Careful examination of reconstruction by region of involvement demonstrated significant advantages in the use of expanded transposition flaps over pure advancement. These advantages and the modifications in the design of expanded flaps for each body region are discussed in a series of representative cases. They emphasize the ability of transposition flaps to dissipate tension away from the flap apex and distribute it more proximally, thus redirecting the tension lines so there is less likelihood of anatomic distortion in the reconstructed area. Also, flaps designed in this manner allow improved contour by avoiding webbing, tenting across concavities, and bunching of skin laterally. The authors conclude that restricting the expanded flap design to advancement alone to minimize potential scarring severely limits the reconstructive capabilities of the added tissue and distracts from the surgeon's ability to accomplish the initial reconstructive goal. The cost of additional incisions is worthwhile to achieve better final contour of the reconstructed part, lesser risk of anatomic distortion, better position of the scars, and lowered risk of scar contracture.

Large and Giant Congenital Pigmented Nevi of the Upper Extremity: An Algorithm to Surgical Management

The timing and choice of treatment of congenital giant pigmented nevi continues to evolve under the influence of changing opinions regarding the risk of malignant degeneration and the impact of excision and reconstruction on the affected child. Many studies exist to support a notable enough risk of malignancy to warrant excision, yet other series and pigmented lesion clinics suggest that the risk of malignancy does not warrant the potential scarring and deformity that has followed the surgery necessary to remove these giant lesions. To satisfy both sides in this controversy, we have been challenged to modify our surgical techniques in a manner that minimizes the risk of malignant degeneration and at the same time provides optimal functional and aesthetic outcomes for these complex reconstructions. Thirty consecutive patients with large and giant nevi of the upper extremity were treated over a 23-year period (1979-2002) by the senior author. These patients represent a subset of 259 children (12%) with large or giant congenital pigmented nevi treated and followed during this period of time. In proximal upper extremity lesions, expanded transposition flaps from the upper back and shoulder have effectively eliminated contour defects or circumferential constriction in the upper arm and axilla. An expanded free transverse rectus abdominis musculocutaneous flap has offered a possible avenue for larger lesions (shoulder and upper extremity to below the elbow), and pedicle flaps from the flank (both expanded and nonexpanded) have offered ways of improving the long-term contour in the forearm. Expanded and nonexpanded full-thickness skin grafts were chosen for reconstruction of the hand and the fingers. The authors describe in detail the surgical strategies and the techniques for reconstruction of each region of the upper extremity and then bring these ideas together in an algorithm for assessment and treatment of these challenging lesions.

Abrogation of E-cadherin-mediated adhesion induces tumor cell invasion in human skin-like organotypic culture

The role of cell-cell adhesion in the transition from premalignancy to invasive cancer is not well understood. The purpose of this study was to determine how abrogation of E-cadherin-mediated adhesion influenced early neoplastic progression in tissues that mimic human, premalignant disease. To accomplish this, E-cadherin function was abrogated in a human cell line representing an early stage in the transformation process (HaCaT-II-4 cells) that was grown in three-dimensional, organotypic cultures with intact basement membrane. Before modification, this cell line showed a paucity of cell adhesion structures by ultrastructural and immunohistochemical analysis, whereas immunoblot studies demonstrated that expression and association of E-cadherin and catenins were not diminished when compared with normal keratinocytes. To further reduce functional E-cadherin, II-4 cells were infected with a dominant-negative, recombinant adenovirus, expressing E-cadherin lacking an extracellular domain (AdECadEC). AdECadEC infection resulted in loss of endogenous E-cadherin and completely disrupted II-4 cell adhesion, as seen by loss of beta-catenin from II-4 cell junctions in monolayer culture. In three-dimensional cultures, AdECadEC-infected cells demonstrated disruption of tissue architecture, loss of cell-cell adhesion, and the invasion of individual tumor cells into the stroma. The induction of this invasive phenotype was associated with loss of basement membrane integrity, as seen by degradation of type IV collagen and laminin 5. These studies showed that loss of E-cadherin-mediated adhesion enabled acquisition of an invasive phenotype, suggesting that maintenance of intercellular adhesion and tissue organization plays a crucial part in suppressing the incipient stages of squamous cell cancer progression.

Distraction Osteogenesis of the Mandible With an Internal Bioresorbable Device

Lengthening of the mandible by distraction osteogenesis has been shown to be an effective treatment of hypoplastic mandibles. Use of an internal technique with a bioresorbable distraction device is presented. Mandibular lengthening was performed in seven patients aged 3.2 to 7 years. Six of the patients were diagnosed with craniofacial microsomia, anthe buccal aspect of the mandible, and distraction was started on the second postoperative day at the rate of d one was diagnosed with Nager syndrome. An internal bioresorbable device was placed along 1 mm/d and continued for 17 to 20 days. The distractor screw was maintained for retention for an additional 6 weeks and was then removed. All the patients showed clinical improvement. The postdistraction craniofacial computed tomography scans demonstrated elongation of the mandible with increase in the bony mass. The complications included device failure in one patient. The advantage of this method compared with the internal metal device is that it does not necessitate an additional procedure for device removal.

Connexin 36 in bovine retina: lack of phosphorylation but evidence for association with phosphorylated proteins

In vertebrate retina interneuronal communication through gap junctions is involved in light adaptation and in the transfer of visual information from the rod pathway to the cone pathway. Reports over the last two decades have indicated that these gap junctions are regulated by cyclic nucleotide-dependent protein kinases suggesting that the gap junction proteins, connexins, are phosphorylated. Though all the connexins involved in light adaptation and information transfer from rod to cone pathway are not yet known, connexin 36 has been shown to be definitively involved in the latter process. We have therefore attempted to investigate the cyclic nucleotide-dependent phosphorylation of this connexin in bovine retina. We found several soluble and membrane proteins in bovine retina whose phosphorylation was regulated by cyclic nucleotides. However, no protein of about 36 kDa with cyclic nucleotide-regulated phosphorylation was found in gap junction-enriched membrane preparations. A 36-kDa phosphorylated protein was found in gap junction-enriched membranes phosphorylated in the presence of calcium. However, this protein was not immunoprecipitated by anti-connexin 36 antibodies indicating that it was not connexin 36 in spite of its similarity in molecular weight. Immunoprecipitation did reveal phosphorylated proteins coimmunoprecipitated with connexin 36. Two of these proteins were identified as beta and alpha tubulin subunits. Though cyclic GMP and calcium did not greatly influence the association of these proteins with connexin 36, the results suggest the possibility of connexin 36 associating with other proteins. Together, these observations indicate that interneuronal communication at gap junctions made by connexin 36 may not be regulated by direct phosphorylation of connexin 36, but possibly by phosphorylation of associated proteins.

Analysis of microenvironmental factors contributing to basement membrane assembly and normalized epidermal phenotype

To understand further the role of the dynamic interplay between keratinocytes and stromal components in the regulation of the growth, differentiation, morphogenesis, and basement membrane assembly of human stratified squamous epithelium, we have generated novel, three-dimensional organotypic cultures in which skin keratinocytes were grown in the absence or presence of pre-existing basement membrane components and/or dermal fibroblasts. We found that keratinocytes cultured in the presence of pre-existing basement membrane components and dermal fibroblasts for 9 d showed rapid assembly of basement membrane, as seen by a nearly complete lamina densa, hemidesmosomes, and the polarized, linear distribution of laminin 5 and a6 integrin subunit. Basement membrane assembly was somewhat delayed in the absence of dermal fibroblasts, but did occur at discrete nucleation sites when pre-existing basement membrane components were present. No basement membrane developed in the absence of pre-existing basement membrane components, even in the presence of dermal fibroblasts. Bromodeoxyuridine incorporation studies showed that early keratinocyte growth was independent of mesenchymal support, but by 14 d, both fibroblasts and assembled basement membrane were required to sustain growth. Normalization of keratinocyte differentiation was independent of both dermal fibroblasts and structured basement membrane. These results indicated that epithelial and mesenchymal components play a coordinated role in the generation of structured basement membrane and in the regulation of normalized epithelial growth and tissue architecture in an in vitro model of human skin.

Juvenile xanthogranuloma invading the muscles in the head and neck: clinicopathological case report

Juvenile xanthogranuloma (JXG) is a member of the non-Langerhans cell group of histiocytic proliferative disorders. It typically presents as a solitary, benign, rapidly growing cutaneous tumor that may regress spontaneously. Most cutaneous lesions of JXG occur in the head and neck region of infants and young children. JXG has been documented in many visceral locations including the lung, bone, testis, gastrointestinal tract, kidney, heart, eye, and oral cavity. Intramuscular location is extremely rare. The few intramuscular lesions that have been described involve the trunk, with the musculature of the back involved most frequently. The authors present a patient with juvenile xanthogranuloma on her chin deeply invading the underlying facial muscles. Histopathological analysis confirmed the intramuscular extension. To the authors' knowledge, this is the first detailed clinicopathological report of juvenile xanthogranuloma infiltrating the muscles in the head and neck.