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Approaches to manage nonalcoholic fatty liver disease (NAFLD) are limited by an incomplete understanding of disease pathogenesis. The aim of this study was to identify hepatic gene-expression patterns associated with different patterns of liver injury in a high-risk cohort of adults with obesity. Using the NanoString Technologies (Seattle, WA) nCounter assay, we quantified expression of 795 genes, hypothesized to be involved in hepatic fibrosis, inflammation, and steatosis, in liver tissue from 318 adults with obesity. Liver specimens were categorized into four distinct NAFLD phenotypes: normal liver histology (NLH), steatosis only (steatosis), nonalcoholic steatohepatitis without fibrosis (NASH F0), and NASH with fibrosis stage 1-4 (NASH F1-F4). One hundred twenty-five genes were significantly increasing or decreasing as NAFLD pathology progressed. Compared with NLH, NASH F0 was characterized by increased inflammatory gene expression, such as gamma-interferon-inducible lysosomal thiol reductase (IFI30) and chemokine (C-X-C motif) ligand 9 (CXCL9), while complement and coagulation related genes, such as C9 and complement component 4 binding protein beta (C4BPB), were reduced. In the presence of NASH F1-F4, extracellular matrix degrading proteinases and profibrotic/scar deposition genes, such as collagens and transforming growth factor beta 1 (TGFB1), were simultaneously increased, suggesting a dynamic state of tissue remodeling. Conclusion: In adults with obesity, distinct states of NAFLD are associated with intrahepatic perturbations in genes related to inflammation, complement and coagulation pathways, and tissue remodeling. These data provide insights into the dynamic pathogenesis of NAFLD in high-risk individuals.

Layer-by-layer nanoparticles are modular drug delivery vehicles that incorporate multiple functional materials through sequential deposition of polyelectrolytes onto charged nanoparticle cores. Here, we combined the multicomponent features and tumor targeting capabilities of layer-by-layer assembly with functional biosensing peptides to create a new class of nanotheranostics. These nanoparticles encapsulate a high weight percentage of siRNA while also carrying a synthetic biosensing peptide on the surface that is cleaved into a urinary reporter upon exposure to specific proteases overexpressed in the tumor microenvironment. Importantly, this biosensor reports back on molecular signatures characteristic to metastatic tumors and associated with poor prognosis – MMP9 protease overexpression. We show this nanotheranostic mediates noninvasive urinary-based diagnostics in mouse models of three different cancers with simultaneous gene silencing in flank and metastatic mouse models of ovarian cancer. This work provides a modular nanotheranostic platform to both perturb and characterize tumors, allowing for simultaneous treatment and monitoring of disease.

At early disease stages, Lewy body disorders are characterized by limbic vs. brainstem α-synucleinopathy, but most preclinical studies have focused solely on the nigrostriatal pathway. Furthermore, male gender and advanced age are two major risk factors for this family of conditions, but their influence on the topographical extents of α-synucleinopathy and the degree of cell loss are uncertain. To fill these gaps, we infused α-synuclein fibrils in the olfactory bulb/anterior olfactory nucleus complex-one of the earliest and most frequently affected brain regions in Lewy body disorders-in 3-month-old female and male mice and in 11-month-old male mice. After 6 months, we observed that α-synucleinopathy did not expand significantly beyond the limbic connectome in the 9-month-old male and female mice or in the 17-month-old male mice. However, the 9-month-old male mice had developed greater α-synucleinopathy, smell impairment and cell loss than age-matched females. By 10.5 months post-infusion, fibril treatment hastened mortality in the 21.5-month-old males, but the inclusions remained centered in the limbic system in the survivors. Although fibril infusions reduced the number of cells expressing tyrosine hydroxylase in the substantia nigra of young males at 6 months post-infusion, this was not attributable to true cell death. Furthermore, mesencephalic α-synucleinopathy, if present, was centered in mesolimbic circuits (ventral tegmental area/accumbens) rather than within strict boundaries of the nigral pars compacta, which were defined here by tyrosine hydroxylase immunolabel. Nonprimate models cannot be expected to faithfully recapitulate human Lewy body disorders, but our murine model seems reasonably suited to (i) capture some aspects of Stage IIb of Lewy body disorders, which displays a heavier limbic than brainstem component compared to incipient Parkinson's disease; and (ii) leverage sex differences and the acceleration of mortality following induction of olfactory α-synucleinopathy.

Blood clotting disorders such as pulmonary embolism are associated with high morbidity and mortality. A large portion of thrombotic events occur postoperative and after hospital discharge. Therefore, easily applicable, noninvasive, and long-term monitoring of thrombosis occurrence is critical for urgent clinical intervention. Here, the use is proposed of ionic liquids as a skin transport facilitator to deliver thrombin-sensitive nanosensors that enable prolonged monitoring of pulmonary embolism. Co-formulation of nanosensors with choline and geranic acid (CAGE) ionic liquids demonstrates significant transdermal diffusion into the dermis of the skin and provides sustained release into the blood throughout 72 h. Upon reaching the systemic circulation, the nanosensors release reporter molecules into the urine by responding to activation of the clotting cascade and retain a diagnostic power for 24 h in an acute pulmonary embolism mouse model. These results demonstrate a proof-of-concept disease monitoring system that can be topically applied by patients and potentially reduce mortality and high cost of hospitalization.

The ability to remotely trigger CRISPR/Cas9 activity would enable new strategies to study cellular events with greater precision and complexity. In this work, we have developed a method to photocage the activity of the guide RNA called "CRISPR-plus" (CRISPR-precise light-mediated unveiling of sgRNAs). The photoactivation capability of our CRISPR-plus method is compatible with the simultaneous targeting of multiple DNA sequences and supports numerous modifications that can enable guide RNA labeling for use in imaging and mechanistic investigations.

Postoperative infection and thromboembolism represent significant sources of morbidity and mortality but cannot be easily tracked after hospital discharge. Therefore, a molecular test that could be performed at home would significantly impact disease management. The laboratory has previously developed intravenously delivered “synthetic biomarkers” that respond to dysregulated proteases to produce a urinary signal. These assays, however, have been limited to chronic diseases or acute diseases initiated at the time of diagnostic administration. Here, a subcutaneously administered sustained-release system, using small poly(ethylene glycol) scaffolds (

Formation of capillary blood vasculature is a critical requirement for native as well as engineered organs and can be induced in vitro by co-culturing endothelial cells with fibroblasts. However, whether these fibroblasts are required only in the initial morphogenesis of endothelial cells or needed throughout is unknown, and the ability to remove these stromal cells after assembly could be useful for clinical translation. In this study, we introduce a technique termed CAMEO (Controlled Apoptosis in Multicellular Tissues for Engineered Organogenesis), whereby fibroblasts are selectively ablated on demand, and utilize it to probe the dispensability of fibroblasts in vascular morphogenesis. The presence of fibroblasts is shown to be necessary only during the first few days of endothelial cell morphogenesis, after which they can be ablated without significantly affecting the structural and functional features of the developed vasculature. Furthermore, we demonstrate the use of CAMEO to vascularize a construct containing primary human hepatocytes that improved tissue function. In conclusion, this study suggests that transient, initial support from fibroblasts is sufficient to drive vascular morphogenesis in engineered tissues, and this strategy of engineering-via-elimination may provide a new general approach for achieving desired functions and cell compositions in engineered organs.

Engineered tissue models comprise a variety of multiplexed ensembles in which combinations of epithelial, stromal, and immune cells give rise to physiologic function. Engineering spatiotemporal control of cell-cell and cell-matrix interactions within these 3D multicellular tissues would represent a significant advance for tissue engineering. In this work, a new method, entitled CAMEO (Controlled Apoptosis in Multicellular tissues for Engineered Organogenesis) enables the non-invasive triggering of controlled apoptosis to eliminate genetically-engineered cells from a pre-established culture. Using this approach, the contribution of stromal cells to the phenotypic stability of primary human hepatocytes is examined. 3D hepatic microtissues, in which fibroblasts can enhance phenotypic stability and accelerate aggregation into spheroids, were found to rely only transiently on fibroblast interaction to support multiple axes of liver function, such as protein secretion and drug detoxification. Due to its modularity, CAMEO has the promise to be readily extendable to other applications that are tied to the complexity of 3D tissue biology, from understanding in vitro organoid models to building artificial tissue grafts.

Synovial sarcomas (SS) are soft tissue sarcomas with poor prognosis, displaying a lack of response to conventional cytotoxic chemotherapy. Although SS cell lines have moderate chemosensitivity to isofamide and doxorubicin therapy, the clinical prognosis is still poor. In this article, we showed that flavokawain B (FKB), a novel chalcone from kava extract, potently inhibits the growth of SS cell lines SYO-I and HS-SY-II through induction of apoptosis. Treatment with FKB increased caspase 8, 9, and 3/7 activity compared to vehicle-treated controls, indicating that both extrinsic and intrinsic apoptotic pathways were activated. Furthermore, FKB treatment of both cell lines resulted in increased mRNA and protein expression of death receptor-5 and the mitochondrial pro-apoptotic proteins Bim and Puma, while down-regulating the expression of an inhibitor of apoptosis, survivin in a dose-dependent manner. Our results suggest the natural compound FKB has a pro-apoptotic effect on SS cell lines. FKB may be a new chemotherapeutic strategy for patients with SS and deserves further investigation as a potential agent in the treatment of this malignancy.

While many studies have focused on modulating the immune response and enhancing axonal regeneration after spinal cord injury (SCI), there is limited work being performed on evaluating the role of glial scar in SCI. We sought to evaluate the effects of glial scar resection in contusion models and dorsal hemisection models of SCI. At one week postinjury, 2mm of glial scar was excised from specimens in one of the two groups from each injury model. Functional outcome was measured weekly using the Basso, Beattie, Bresnahan (BBB) Locomotor Rating Scale along with histologic evaluation of spinal cord tracts to determine axonal regeneration. Within the dorsal hemisection model, there was no significant difference in recovery for animals that underwent glial scar excision versus animals that did not have scar excision (p=0.61). Animals subjected to the contusion model, however, demonstrated lower BBB scores in the glial resection group during the earlier postoperative periods (0.05 for differences among the three groups). While glial scar may serve to stabilize the preserved axonal tracts and thereby permit modest recovery in a contusion model of SCI, it may be of less importance with a dorsal hemisection model. These experiments highlight that basic biologic processes following SCI may vary tremendously based on the injury mechanism and that the role of glial scar in spinal cord regeneration must be elucidated.

In the design of nanoparticles that can target disease tissue in vivo, parameters such as targeting ligand density, type of target receptor, and nanoparticle shape can play an important role in determining the extent of accumulation. Herein, a systematic study of these parameters for the targeting of mouse xenograft tumors is performed using superparamagnetic iron oxide as a model nanoparticle system. The type of targeting peptide (recognizing cell surface versus extracellular matrix), the surface coverage of the peptide, its attachment chemistry, and the shape of the nanomaterial [elongated (nanoworm, NW) versus spherical (nanosphere, NS)] are varied. Nanoparticle circulation times and in vivo tumor-targeting efficiencies are quantified in two xenograft models of human tumors (MDA-MB-435 human carcinoma and HT1080 human fibrosarcoma). It is found that the in vivo tumor-targeting ability of the NW is superior to that of the NS, that the smaller, neutral CREKA targeting group is more effective than the larger, positively charged F3 molecule, that a maximum in tumor-targeting efficiency and blood half-life is observed with approximately 60 CREKA peptides per NW for either the HT1080 or the MDA-MB-435 tumor types, and that incorporation of a 5-kDa polyethylene glycol linker improves targeting to both tumor types relative to a short linker. It is concluded that the blood half-life of a targeting molecule-nanomaterial ensemble is a key consideration when selecting the appropriate ligand and nanoparticle chemistry for tumor targeting.

Aims To characterize the effect of urodynamic diagnosis on degree of incontinence related bother and health related quality of life in a large, multi-ethnic population of women. Methods Effects of multichannel urodynamic diagnosis, urethral competency, and other patient characteristics on abbreviated Urogenital Distress Inventory (UDI6) and Incontinence Impact Questionnaire (IIQ7) composite scores were analyzed retrospectively. Results Six hundred eleven patients were included. Mean UDI6 and IIQ7 scores were significantly higher among patients with mixed incontinence, detrusor overactivity, urinary stress incontinence with overactive bladder, and negative studies compared to those with stress incontinence without OAB. The relative composite UDI6 and IIQ7 mean scores did not significantly differ between the mixed incontinence, detrusor overactivity, stress incontinence with OAB and negative study groups. UDI6 and IIQ7 scores were significantly higher among stress incontinent patients with intrinsic sphincter deficiency, but similar among mixed incontinent patients with intrinsic sphincter deficiency. Conclusion Urodynamic diagnoses of detrusor overactivity, mixed incontinence, and stress incontinence with overactive bladder are associated with significantly worse incontinence related bother and health related quality of life when compared to those with stress incontinence without OAB. These conditions appear to have similar degree of impact on incontinence related bother and quality of life. Patients presenting with symptoms of incontinence can suffer a similar compromise in quality of life despite a negative MCUD study. Neurourol. Urodynam. 28:183–187, 2009. © 2008 Wiley-Liss, Inc.

Nanomaterials modified with biological recognition motifs acquire a myriad of functions that can be exploited for the diagnosis and treatment of cancer. Nevertheless, while bioactive domains can be used to target nanoparticles to cell receptors, shuttle them across cell membranes, and activate cell signaling, such modifications typically include cationic or hydrophobic regions that lead to rapid reticuloendothelial system (RES) clearance of particles from the blood, ultimately reducing particle accumulation in tumors. [1,2] Further functionalization with hydrophilic polymers like poly(ethylene glycol) (PEG) can improve blood half-lives and tumor accumulation, but often at the expense of efficient ligandmediated nanoparticle binding. [3‐5] To address this tradeoff between improved biodistribution and optimal functionality on nanoparticles, we present a general strategy for reversibly veiling bioactive domains on nanoparticles using sterically protective polymers. We demonstrate that these materials effectively accumulate via the hyperpermeable vasculature of tumors and can be activated by cancer-secreted proteases to unveil hidden functional domains.

It is widely accepted that there is Griffiths phase (GP) present in the paramagnetic phase in doped manganites. We studied the effect of quenched disorder on the region of GP in connection with the temperature dependence of the line width (Delta H) of the electron paramagnetic resonance (EPR) in La0.67-2xNd2xCa0.33-xSrxMnO3 (x = 0, 0.1, 0.15, 0.2 and 0.25). With this approach it is found that Delta H(T), the minimum in the line width (Delta H-min) and T-min are reproduced. With increasing values of the quenched disorder the values of Delta H-min are found to increase. A numerical relation that correlates the temperature range in which GP exists and the cation size disorder is obtained and found to be in agreement with some reported data. (C) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reversible self-assembly is ubiquitous in Nature. The ability to dynamically control the assembly and disassembly of biomolecular complexes is essential to higher-order biological processes, including the control of intracellular communication, gene expression, and platelet aggregation upon injury. To date, assembly or disassembly of nanoparticles (NPs) has been exploited to improve sensitivity for detection of single biomolecular targets, including DNA, small molecules, proteins, and pH changes in vitro; however, mechanisms of sensing that allow multiple, opposing stimuli to dynamically assemble and dis-assemble NPs have not been described. Development of inorganic nanoparticles that respond to multiple, antagonistic biological signals could facilitate sensing of the physiologic balance between opposing effectors of cellular and tissue function. Herein, we introduce a nanoparticle (NP) system where self-assembly is dynamically coupled to the balance between the classic antagonistic enzymes: tyrosine kinase and phosphatase. In vivo, these enzymes regulate cellular communication, gene expression, and ultimately cell life and death through the phosphorylation and dephosphorylation of tyrosine residues on other proteins Their dysregulation contributes significantly to the development of cancer and other inflammatory diseases. Here, kinase-induced superparamagnetic nanoassemblies enhance the T2 relaxation of hydrogen atoms at picomolar enzyme concentrations and are shown to be fully reversible by introducing excess phosphatase activity. In the future, these nanomaterials may be optimized to report the balance between these cytosolic enzyme activities and may facilitate new screens for inhibitors in vitro and in vivo. Additionally, extensions of this design logic may be synthesized to probe the dynamics of a diversity of antagonistic biologic processes. To construct a system of NPs that could coalesce in the presence of kinase activity and re-disperse in the presence of phosphatase activity, two NP populations were synthesized (Scheme 1). The first population was modified with peptide substrates that may be phosphorylated by Abl tyrosine kinase and dephosphorylated by a phosphatase. The second popula

Extracellular matrix (ECM) mole- cules have been shown to function as cues for neurite guidance in various populations of neurons. Here we show that laminin (LN) and fibronectin (FN) presented in stripe micro-patterns can provide guidance cues to neonatal (P5) inner ear spiral ganglion (SG) neurites. The response to both ECM molecules was dose-depend- ent. In a LN versus poly-L-lysine (PLL) assay, neurites were more often observed on PLL at low coating con- centrations (5 and 10 lg/mL), while they were more often on LN at a high concentration (80 lg/mL). In a FN versus PLL assay, neurites were more often on PLL than on FN stripes at high coating concentrations (40 and 80 lg/mL). In a direct competition between LN and FN, neurites were observed on LN significantly more often than on FN at both 10 and 40 lg/mL. The data suggest a preference by SG neurites for LN at high con- centrations, as well as avoidance of both LN at low and FN at high concentrations. The results also support a potential model for neurite guidance in the developing inner ear in vivo. LN, in the SG and osseus spiral lamina may promote SG dendrite growth toward the organ of Corti. Within the organ of Corti, lower concentrations of LN may slow neurite growth, with FN beneath each row of hair cells providing a stop or avoidance signal. This could allow growth cone filopodia increased time to sample their cellular targets, or direct the fibers upward toward the hair cells. ' 2007 Wiley Periodicals, Inc. Develop

We have fabricated a hepatic tissue construct using a multilayer photopatterning platform for embedding cells in hydrogels of complex architecture. We first explored the potential of established hepatocyte culture models to stabilize isolated hepatocytes for photoencapsulation (e.g., double gel, Matrigel, cocultivation with nonparenchymal cells). Using photopolymerizable PEG hydrogels, we then tailored both the chemistry and architecture of the hydrogels to further support hepatocyte survival and liver-specific function. Specifically, we incorporated adhesive peptides to ligate key integrins on these adhesion-dependent cells. To identify the appropriate peptides for incorporation, the integrin expression of cultured hepatocytes was monitored by flow cytometry and their functional role in cell adhesion was assessed on full-length extracellular matrix (ECM) molecules and their adhesive peptide domains. In addition, we modified the hydrogel architecture to minimize barriers to nutrient transport for these highly metabolic cells. Viability of encapsulated cells was improved in photopatterned hydrogels with structural features of 500 microm in width over unpatterned, bulk hydrogels. Based on these findings, we fabricated a multilayer photopatterned PEG hydrogel structure containing the adhesive RGD peptide sequence to ligate the alpha5beta1 integrin of cocultured hepatocytes. Three-dimensional photopatterned constructs were visualized by digital volumetric imaging and cultured in a continuous flow bioreactor for 12 d where they performed favorably in comparison to unpatterned, unperfused constructs. These studies will have impact in the field of liver biology as well as provide enabling tools for tissue engineering of other organs.

Successful development of cell-biased bioartificial liver devices necessitates the establishment of techniques and designs for long-term, stable hepatocellular function and efficient transport of nutrients and wastes within the device. Given the relatively large cell mass that one must consider, one possible solution involves the use of micropatterning technology to sandwich hepatocytes aligned in rows between two micropatterned surfaces. Rows of cells would alternate with hepatocyte-free areas, creating efficient transport channels for fluid flow and nutrient exchange. Ultimately, this type of device could also be used as a three-dimensional construct for investigating a variety of cell-surface, cell-extracellular matrix, and cell-cell interactions. To achieve this goal, one must develop techniques for selectively adhering hepatocytes to solid substrates. In this study, reproducible, selective adhesion of hepatocytes on a glass substrate with large regions of adhesive (AS) and nonadhesive (NAS) surfaces was obtained. The AS had hydrophilic characteristics, enhancing deposition of collagen molecules from an aqueous solution, and subsequent hepatocyte adhesion, whereas the NAS had hydrophobic properties and remained collagen-free and hepatocyte-free. In addition, a reproducible processing technique for obtaining patterns of hepatocytes was developed and optimized, using a surface with a single AS band as a first approximation to a micropatterned device. This was achieved by spincoating an aqueous collagen type I solution (0.1 mg/mL) on a banded surface at 500 rpm for 25 seconds. The morphology and long-term function of the hepatocytes attached to AS in nonbanded and banded surface configurations was assessed by mimicking sandwich culture and was shown to be similar to stable, differentiated sandwich cultures. Mathematical modeling was used to determine critical design criteria for the hypothetical micropatterned device. The oxygen distribution and viscous pressure drop were modeled along a typical microchannel and limited to in vivo values. An optimal channel length of 0.6 cm and a flow rate of 2.0 x 10(-6) mL/s were obtained for a channel of 100 microns in width and 10 microns in height. These values were reasonable in terms of practical implementation.

We have developed a perfusion bioreactor system that allows the formation of steady state oxygen gradients in cell culture. In this study, gradients were formed in cultures of rat hepatocytes to study the role of oxygen in modulating cellular functions. A model of oxygen transport in our flat-plate reactor was developed to estimate oxygen distribution at the cell surface. Experimental measurements of outlet oxygen concentration from various flow conditions were used to validate model predictions. We showed that cell viability was maintained over a 24-h period when operating with a physiologic oxygen gradient at the cell surface from 76 to 5 mmHg O(2) at the outlet. Oxygen gradients have been implicated in the maintenance of regional compartmentalized metabolic and detoxification functions in the liver, termed zonation. In this system, physiologic oxygen gradients in reactor cultures contributed to a heterogeneous distribution of phosphoenolpyruvate carboxykinase (predominantly localized upstream) and cytochrome p450 2B (predominantly localized downstream) that correlates with the distribution of these enzymes in vivo. The oxygen gradient chamber provides a means of probing the oxygen effects in vitro over a continuous range of O(2) tensions. In addition, this system serves as an in vitro model of zonation that could be further extended to study the role of gradients in ischemia-reperfusion injury, toxicity, and bioartificial liver design.

Previous studies on customizing cell culture environments have utilized a variety of microfabrication-based tools to control the spatial localization of adhesive proteins and subsequently mammalian cells. Others have used various methods to immobilize nonadhesive PEO-based polymers on surfaces to inhibit protein absorption and cell adhesion. In this study, we report the application of a well-characterized, commercially available, PEO-terminated triblock polymer (Pluronic F108) to create micropatterned nonadhesive domains on a variety of biomaterials that deter cell adhesion for up to 4 weeks in culture. The Pluronic can be applied using microfluidic tools or photolithographic techniques, and can be adsorbed to a variety of common surfaces including tissue culture polystyrene, methylated glass, silicone, and polylactic-co-glycolic acid. The effectiveness of the Pluronic in inhibiting cell adhesion in the presence of collagen I is also quantified. Finally, these patterning techniques are generalized to control tissue organization on a variety of common biomaterials. This simple method for micropatterning PEO and, therefore, proteins and cells should prove useful as a tool for biomolecular surface engineering.

We report the prenatal diagnosis, at 18 weeks' gestational age of a del(8)(p23.1-->pter) in a fetus with an atrio-ventricular canal, persistent left superior vena cava and hypoplastic right ventricle detected by sonographic imaging. We further refine the breakpoints associated with this defect using fluorescent in situ hybridization analysis (FISH). Our findings correlate with recent reports of the localization and importance of GATA4 (a zinc finger transcription factor) in cardiac development. Though microcephaly, mental retardation and typical behavioural features are well described in various deletions in 8p, the absence of notable microcephaly in this case raises the possibility for a separate genetic aetiology for some of these features. Indeed, primary autosomal recessive microcephaly (MCPH1) was recently mapped to a nearby region and may be the cause for this frequent observation in some cases of 8p deletions. These observations illustrate the role of FISH in prenatal diagnosis and refinement of chromosomal breakpoints. In addition, mappings of loci significant for cardiac development are presented. Our findings suggest that some features of the 8p deletion syndrome may ultimately be uncoupled from one another, and underscore the need for further study of this region of chromosome 8, in order to achieve adequate information for genetic counselling.

The repair or replacement of damaged tissues using in vitro strategies has focused on manipulation of the cell environment by modulation of cell-extracellular matrix interactions, cell-cell interactions, or soluble stimuli. Many of these environmental influences are easily controlled using macroscopic techniques; however, in co-culture systems with two or more cell types, cell-cell interactions have been difficult to manipulate precisely using similar methods. Although microfabrication has been widely utilized for the spatial control of cells in culture, these methods have never been adapted to the simultaneous co-cultivation of more than one cell type. We have developed a versatile technique for micropatterning of two different cell types based on existing strategies for surface modification with aminosilanes linked to biomolecules and the manipulation of serum content of cell culture media. This co-culture technique allowed manipulation of the initial cellular microenvironment without variation of cell number. Specifically, we were able to control the level of homotypic interaction in cultures of a single cell type and the degree of heterotypic contact in co-cultures over a wide range. This methodology has potential applications in tissue engineering, implant biology, and developmental biology, both in the arena of basic science and optimization of function for technological applications.

To review the clinical and urodynamic outcome of treatment by the modified Pereyra procedure in 93 women with genuine stress incontinence.Retrospective review.Harbor/UCLA Medical Center and Los Angeles County Women's Hospital, Los Angeles, California, USA.Clinical and urodynamic assessment one year after modified Pereyra procedure.Overall 82% of patients were subjectively cured while only 63% were objectively cured. Women with failed surgery had significantly lower pre-operative maximum urethral closure pressures. The procedure had a low operative and postoperative morbidity with no significant disturbance of voiding function noted at one year follow-up.Our results with the modified Pereyra procedure for stress incontinence showed a significantly lower success rate than has been reported from many previous studies.

ObjectiveZenker's diverticula occur primarily in older patients, resulting in dysphagia, aspiration, and weight loss. A number of surgical options are available for treatment. While small diverticula (smaller than 2 cm) may require no surgical treatment, the presence of dysphagia, asiration, may necessitate surgery. Surgical options include both traditional open and endoscopic procedures. Many patients are elderly and cannot undergo open surgical procedures. Endoscopic techniques have become the preferred approaches by physicians because of their safety, effectiveness, and fewer complications.MethodsRetrospective chart review of 65 patients who underwent endoscopic carbon dioxide (CO2) laser treatment of Zenker's diverticulum at a single tertiary care institution. In some of the procedures, the incision was sealed with a tissue sealant.ResultsAge ranged from 56 to 89 years. All patients had significant improvement in their symptoms such as dysphagia, aspiration, and weight gain. The endoscopic incision wa...

Objectives: To determine the significance of in-hospital rehabilitation facility versus distant rehabilitation facilities in the outcomes and complications of postoperative head and neck surgical patients. Methods: Retrospective review of head and neck surgical patients over a 5-year period at a tertiary care medical center. Results: Fifty patients met criteria for this study (35 males, 15 females). Forty-two patients had a primary squamous cell carcinoma, and 8 patients had other primary malignancy of the head and neck. Thirty-two patients were placed in an in-hospital rehabilitation facility, and 18 patients were placed in distant rehabilitation facilities (average distance 40.9 miles; range 2–250 miles). Seventeen patients (34%) had complications including infection/drainage (7 patients), fistula (6 patients), pneumonia (2 patients), wound dehiscence (2 patients), bleeding from carotid stump, fluctuance, exudate, ulcer, eschar, delay in Blom-Singer valve teaching and displacement. The difference between the rate of complications among the 2 groups was not statistically significant (37.5% in-hospital rehabilitation, 27.8% distant rehabilitation; P = 0.496). The difference between the rate of hospital readmission was not statistically significant either (25% for in-hospital rehabilitation patients and 16.7% for distant rehabilitation patients; P = 0.505). The average length of stay of patients without complications was 18.5 days (SD = 17) for in-hospital rehabilitation and 12.9 days (SD = 5.8) for distant rehabilitation. This difference was not statistically significant (P = 0.346). Conclusion: One third of postoperative head and neck surgical patients developed complications while in a rehabilitation facility. The length of stay, hospital re-admission rate, and frequency of complications does not correlate with the distance of the rehabilitation facility from the treating institution.

Purpose: Spinal metastases often requires Kyphoplasty (used to stabilize a collapsed vertebral body and relieve pain by injecting a cement mixture into the vertebral body) followed by palliative fractionated external beam radiotherapy. We propose to combine these two treatments into a single procedure (spinal brachytherapy) by adding a β‐emitting radionuclide to the kyphoplasty cement, thereby irradiating the bone from within. The potential advantages of this approach include delivery of a higher dose to the vertebral body, limiting the radiationdose to the spinal cord (due to the limited range of β‐particles in tissue) and eliminating the need for repeat patient visits for palliative radiotherapy.Method and Materials: The feasibility of the proposed procedure was studied by creating a CT‐based voxelized model of a T6 vertebral body, coupled with radiation transport using Monte Carlo N‐Particle code (MCNPX Version 2.5). A cylindrical source representing the injected cement was introduced into the voxelized model. Four β‐emitters, Y‐90, P‐32, Sr‐89 and Re‐188 were chosen as candidate isotopes for the simulations. Each simulation consisted of thirty million histories. The dose deposited in each voxel was used to generate isodose curves and dose‐volume histograms, yielding comparisons of dose to the vertebral body and the spinal cord. The activity of each radionuclide necessary to deliver a dose of 60 Gy to the vertebral body was calculated. The corresponding dose to the spinal cord was also determined. Results:Dose‐volume histograms and isodose line overlays for the different radionuclides indicate activities ranging from 0.5 – 950 mCi, will deliver the target dose to the vertebral body. Conclusions: Present work indicates that β‐emitting radionuclides can be safely used to irradiate the vertebral body while sparing the spinal cord. Future work will involve determining the radionuclide most suitable for this application based on different dosimetric and design considerations.

865 children in their first year of full-time education in the health area of Lambeth, Southwark and Lewisham were examined for dental fitness and treatment requirements. Seventy-six percent of the subjects examined required treatment for dental caries and the mean dmft was 4.85. Sixteen percent of erupted permanent first molars were carious. 404 children had marginal gingivitis. All the treatment required for gingivitis and 82% for caries could be carried out by dental auxiliaries. The need for preventive measures is discussed.

Summary— In order to study the effect of urinary infections upon the incidence of bladder instability during cystometric evaluation, 15 women underwent cystometry during the course of significant bacteriuria (105 organisms/ml) and again 2 weeks after treatment. The pre-treatment incidence of bladder instability (53%) dropped by 50% following treatment of the infection but other cystometric measurements remained unchanged. Urinary tract infections must be treated adequately before treating bladder instability.

In order to explain the pathophysiology of urinary urgency frequency observed following the administration of thyroid releasing hormone (TRH) during thyroid function testing, simultaneous urethrocystometry was performed in six females before and after TRH administration, and in another five females before and after administration of normal saline (control group). Within a few minutes following TRH administration, a statistically significant and consistent drop in maximal urethral pressure and concomitant sensation of urinary urgency in the absence of significant changes in true detrusor pressure suggested the presence of a reflex neuronally mediated motor component to this sensory effect of urinary urgency. The absence of urethral and detrusor pressure changes in the control group reinforced the TRH-mediated origin of urinary urgency.