A new technique for the surgical management of unstable thoracolumbar burst fractures: a modification of the anterior approach and an outcome comparison to traditional methods.

This study was conducted to determine the safety, efficacy, and complication rate associated with the anterior approach in the use of a new titanium mesh interbody fusion cage for the treatment of unstable thoracolumbar burst fractures. The experience with this technique is compared with the senior authors' (C.S.

Percutaneous vertebroplasty in vertebral osteonecrosis (Kummell's spondylitis).

The authors report the clinical symptoms and response to therapy of a series of patients who presented with subacute or chronic back pain due to vertebral osteonecrosis (Kummell's spondylitis) and who underwent percutaneous vertebroplasty. The authors performed a retrospective chart review of a series of 95 patients in whom 149 painful, nonneoplastic compression fractures were demonstrated and who were treated with percutaneous transpediculate polymethylmethacrylate (PMMA) vertebroplasty. In six of these patients there was evidence of vertebral osteonecrosis, as evidenced by the presence of an intravertebral vacuum cleft on radiography or by intravertebral fluid on magnetic resonance (MR) imaging.

Invasion of host cells by Salmonella typhimurium requires focal adhesion kinase and p130Cas.

Salmonella typhimurium colonizes the intestinal epithelium by injecting an array of effector proteins into host cells that induces phagocytic uptake of attached bacteria. However, the host molecules targeted by these effectors remain poorly defined. Here, we demonstrate that S.

Neurotensin stimulates mitogenesis of prostate cancer cells through a novel c-Src/Stat5b pathway.

Neuroendocrine (NE)-like cells are hypothesized to contribute to the progression of prostate cancer by producing factors that enhance the growth, survival or metastatic capabilities of surrounding tumor cells. Many of the factors known to be secreted by NE-like cells, such as neurotensin (NT), parathyroid hormone-related peptide, serotonin, bombesin, etc., are agonists for G-protein-coupled receptors, but the signaling pathways activated by these agonists in prostate tumor cells are not fully defined.

Crosstalk between different adhesion molecules.

Cell adhesion molecules mediate cell-cell and cell-extracellular matrix adhesions, and coordination between these molecules is essential for tissue formation and morphogenesis. Crosstalk between integrins and cadherins may result from a physical response to integrin-mediated adhesion, complex cell differentiation processes, or direct signaling pathways linking the two adhesion systems. Nectins have recently been shown to regulate the organization of cadherins into adherens junctions and the formation of tight junctions by several processes.

Paraxial protocadherin mediates cell sorting and tissue morphogenesis by regulating C-cadherin adhesion activity.

Little is known about how protocadherins function in cell adhesion and tissue development. Paraxial protocadherin (PAPC) controls cell sorting and morphogenetic movements in the Xenopus laevis embryo. We find that PAPC mediates these functions by down-regulating the adhesion activity of C-cadherin.

Surgical approach to posterior skull deformity.

The incidence of occipital skull flattening in infants has recently increased, partly as a result of widespread supine positioning to prevent sudden infant death syndrome. The authors discuss the causes and differential diagnosis of posterior skull deformity in this subpopulation of patients and describe their technique for surgical correction of the condition.

Sagittal synostosis.

Sagittal synostosis causes predictable malformations depending on the specific suture location that fuses. Anterior fusion causes frontal bossing, whereas posterior fusion causes an occipital knob. Complete sagittal synostosis results in deformity both anteriorly and posteriorly.

Understanding and interpreting MRI of the genitourinary tract.

This article familiarizes the urologist with the most common pulse sequences used in MRI to evaluate the kidneys and adrenal glands. It serves as a basis on which interpretation of genitourinary MRI can be facilitated, and includes specifics on how to perform these studies. MRI analysis of renal masses, cysts, and cystic masses is reviewed thoroughly and the critical factor in determining enhancement in renal lesions is detailed.

Imaging of upper extremity stress fractures in the athlete.

Although it is much less common than injuries in the lower extremities, an upper extremity stress injury can have a significant impact on an athlete. If an accurate and timely diagnosis is to be made, the clinician must have a high index of suspicion of a stress fracture in any athlete who is involved in a throwing, weightlifting, or upper extremity weight-bearing sport and presents with chronic pain in the upper extremity. Imaging should play an integral role in the work-up of these patients; if initial radiographs are unrevealing, further cross-sectional imaging should be strongly considered.

Monitoring dynamic protein interactions with photoquenching FRET.

The mammalian cell nucleus is a dynamic and highly organized structure. Most proteins are mobile within the nuclear compartment, and this mobility reflects transient interactions with chromatin, as well as network interactions with a variety of protein partners. To study these dynamic processes in living cells, we developed an imaging method that combines the photoactivated green fluorescent protein (PA-GFP) and fluorescence resonance energy transfer (FRET) microscopy.

Localization of linker histone in chromatosomes by cryo-atomic force microscopy.

Linker histones play a fundamental role in determining higher order chromatin structure as a consequence of their association with nucelosomal DNA. Yet the locations and structural consequences of linker histone binding are still enigmatic. Here, using cryo-atomic force microscopy, we show that the linker histone H5 in native chromatin and in chromatosomes reconstituted on the 5S rDNA template is located at the dyad of the nucleosome core particle, within the "stem" structure.

Novel strategies to attenuate immune activation in Crohn's disease.

Our understanding of the pathogenic mechanisms that underlie the chronic intestinal inflammation characteristic of Crohn's disease (CD) has advanced greatly in recent years. We now realize that effective treatment will not be achieved through non-specific generalized immunosuppression, but rather with the development of well-designed therapies that target specific immunological pathways. The success of infliximab has driven exploration into the blockade of additional pro-inflammatory cytokines, such as interleukin-12 and interferon-gamma.

Skull base chordomas: overview of disease, management options, and outcome.

Cranial base chordomas are locally invasive tumors that, from a midline, clival location, extend in different directions and display various patterns of skull base invasion. Although histologically benign, their invasive nature makes true "oncological" resection virtually impossible to achieve in most cases, despite modern skull base surgical techniques. Moreover, because of the tumor's location and proximity to critical neural and vascular structures, surgery-related morbidity can be significant when an aggressive resection is undertaken.

Meningiomas of the orbit: contemporary considerations.

Meningiomas are the most frequently occurring benign intracranial neoplasms. Compared with other intracranial neoplasms they grow slowly, and they are potentially amenable to a complete surgical cure. They cause neurological compromise by direct compression of adjacent neural structures.

An introductory overview of orbital tumors.

The term "orbital tumors" comprises a wide variety of lesions that often share the same cardinal clinical finding (exophthalmos) and clinical history. Age at presentation, associated ophthalmological findings, and radiological features, however, provide invaluable information as to the possible histological type of tumor. The present article serves as an introductory overview regarding the pathological characteristics, clinical features, radiological characteristics, and principles of treatment of orbital tumors.

T cells in cryptopatch aggregates share TCR gamma variable region junctional sequences with gamma delta T cells in the small intestinal epithelium of mice.

The role of cryptopatch aggregates in the development of intestinal intraepithelial lymphocytes (IEL) is a matter of controversy. Therefore, an important question is whether T cells in cryptopatch aggregates are lineally related to IEL. We hypothesized that if gammadelta+ IEL derive from T cells in cryptopatch aggregates, then a clonal relationship would exist between the two populations.

Role of TL1A and its receptor DR3 in two models of chronic murine ileitis.

TL1A is a TNF-like cytokine that binds to the death-domain receptor (DR)3 and provides costimulatory signals to activated lymphocytes. Through this interaction, TL1A induces secretion of IFN-gamma and may, therefore, participate in the development of T helper-1-type effector responses. In this study, we investigated whether interactions between TL1A and DR3 are involved in the pathogenesis of chronic murine ileitis.

Does "stubbornness" have a role in pediatric constipation?

The objective of this study was to determine if children with constipation are more stubborn, both in general and specifically regarding toileting behaviors, than children without constipation. A secondary objective was to determine if constipated children who are more stubborn are less likely to respond to routine therapeutic interventions than less stubborn constipated children. One hundred one children aged 2 to 6 years, who were first-time presenters (never received treatment) to their primary care physician (PCP) with constipation, were compared with 84 nonconstipated control children of similar age range.

Increased surgical volume is associated with lower THA dislocation rates.

The presumed correlation between an increasing volume of health care procedures and an improvement in outcomes is sometimes referred to as the practice-makes-perfect effect. Growing interest in outcomes-based research has led to numerous papers examining this relationship for various surgical procedures, including total hip arthroplasty. The results of these studies have important implications for consumers, providers, and healthcare financers.

Conditional expression of PTEN alters the androgen responsiveness of prostate cancer cells.

Background: Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is lost as a function of prostate tumor androgen dependence. While the transcriptional activity of the androgen receptor (AR) is inhibited by PTEN in androgen sensitive prostate cancer (CaP), the role of PTEN in androgen disease is unclear.

Methods: We developed a system where PTEN can be conditionally re-expressed at physiologic levels into a PTEN null metastatic human CaP cell line, C4-2, and androgen responsiveness examined.

Low doses of antigen coupled to anti-CR2 mAbs induce rapid and enduring IgG immune responses in mice and in cynomolgus monkeys.

The complement system and B cell complement receptor 2 (CR2), specific for C component C3dg, play important roles in both the innate and adaptive immune response. We used hapten and protein conjugates of anti-CR2 mAbs as models for C3dg-opsonized antigens and immune complexes to examine the handling of and immune response to these reagents in mice and in non-human primates (NHP). Mice immunized and boosted i.

A novel method for gene expression mapping of metastatic competence in human bladder cancer.

Expression profiling by DNA microarray analysis has provided insights into molecular alterations that underpin cancer progression and metastasis. Although differential expression of microarray-defined probes can be related to numerical or structural chromosomal alterations, it is unclear if such changes are also clustered in distinct chromosomes or genomic regions and whether chromosomal alterations always reflect changes in gene expression. Here we apply the dChip algorithm and a novel technique to test the hypothesis that expression changes occurring as a function of tumor progression and metastasis are nonrandomly distributed.