Faculty Bibliography

The use of impacted morselized cancellous bone grafts in conjunction with cementless hemispherical acetabular cups for treatment of AAOS type II acetabular cavitary deficiencies was evaluated in a retrospective study of 23 primary and 24 revision total hip arthroplasties, at a mean follow-up of 7.9 and 8.1 years, respectively. All primary hips received autografts, while all revision hips received allografts. Modified Harris Hip Scores for primary and revision hip replacements increased from a pre-operative mean of 37 and 47 to a postoperative mean of 90 and 86, respectively. All 23 autografts and 23 out of 24 cancellous allografts were radiographically incorporated without evidence of resorption. There were no instances of infection, component migration, or cases requiring subsequent acetabular revision. We conclude that impacted morselized cancellous bone-graft augmentation of cementless cups is a viable surgical option for AAOS type II cavitary acetabular defects

Both the generation and the analysis of proteomics data are now widespread, and high-throughput approaches are commonplace. Protocols continue to increase in complexity as methods and technologies evolve and diversify. To encourage the standardized collection, integration, storage and dissemination of proteomics data, the Human Proteome Organization's Proteomics Standards Initiative develops guidance modules for reporting the use of techniques such as gel electrophoresis and mass spectrometry. This paper describes the processes and principles underpinning the development of these modules; discusses the ramifications for various interest groups such as experimentalists, funders, publishers and the private sector; addresses the issue of overlap with other reporting guidelines; and highlights the criticality of appropriate tools and resources in enabling 'MIAPE-compliant' reporting

Studies in continuously cultured cells have established that familial Alzheimer's disease (FAD) mutant presenilin 1 (PS1) delays exit of the amyloid precursor protein (APP) from the trans-Golgi network (TGN). Here we report the first description of PS1-regulated APP trafficking in cerebral neurons in culture and in vivo. Using neurons from transgenic mice or a cell-free APP transport vesicle biogenesis system derived from the TGN of those neurons, we demonstrated that knocking-in an FAD-associated mutant PS1 transgene was associated with delayed kinetics of APP arrival at the cell surface. Apparently, this delay was at least partially attributable to impaired exit of APP from the TGN, which was documented in the cell-free APP transport vesicle biogenesis assay. To extend the study to APP and carboxyl terminal fragment (CTF) trafficking to cerebral neurons in vivo, we performed subcellular fractionation of brains from APP transgenic mice, some of which carried a second transgene encoding an FAD-associated mutant form of PS1. The presence of the FAD mutant PS1 was associated with a slight shift in the subcellular localization of both holoAPP and APP CTFs toward iodixanol density gradient fractions that were enriched in a marker for the TGN. In a parallel set of experiments, we used an APP : furin chimeric protein strategy to test the effect of artificially forcing TGN concentration of an APP : furin chimera that could be a substrate for beta- and gamma-cleavage. This chimeric substrate generated excess Abeta42 when compared with wildtype APP. These data indicate that the presence of an FAD-associated mutant human PS1 transgene is associated with redistribution of the APP and APP CTFs in brain neurons toward TGN-enriched fractions. The chimera experiment suggests that TGN-enrichment of a beta-/gamma-secretase substrate may play an integral role in the action of mutant PS1 to elevate brain levels of Abeta42

The thyroid is an endocrine gland in all vertebrates that develops from the ventral floor of the anterior pharyngeal endoderm. Unravelling the molecular mechanisms of thyroid development helps to understand congenital hypothyroidism caused by the absence or reduction of this gland in newborn humans. Severely reduced or absent thyroid-specific developmental genes concomitant with the complete loss of the functional gland in the zebrafish hands off (han, hand2) mutant reveals the han gene as playing a novel, crucial role in thyroid development. han-expressing tissues surround the thyroid primordium throughout development. Fate mapping reveals that, even before the onset of thyroid-specific developmental gene expression, thyroid precursor cells are in close contact with han-expressing cardiac lateral plate mesoderm. Grafting experiments show that han is required in surrounding tissue, and not in a cell-autonomous manner, for thyroid development. Loss of han expression in the branchial arches and arch-associated cells after morpholino knock-down of upstream regulator genes does not impair thyroid development, indicating that other han-expressing structures, most probably cardiac mesoderm, are responsible for the thyroid defects in han mutants. The zebrafish ace (fgf8) mutant has similar thyroid defects as han mutants, and chemical suppression of fibroblast growth factor (FGF) signalling confirms that this pathway is required for thyroid development. FGF-soaked beads can restore thyroid development in han mutants, showing that FGFs act downstream of or in parallel to han. These data suggest that loss of FGF-expressing tissue in han mutants is responsible for the thyroid defects.

Meiotic checkpoints monitor chromosome status to ensure correct homologous recombination, genomic integrity and chromosome segregation. In Drosophila the persistent presence of double strand DNA breaks (DSB) activates the ATR/Mei-41 checkpoint, delays progression through meiosis and causes defects in DNA condensation of the oocyte nucleus, the karyosome. Checkpoint activation has also been linked to decreased levels of the TGF+/--like molecule Gurken, which controls normal eggshell patterning. We used this easy scorable eggshell phenotype in a germ line mosaic screen in Drosophila to identify new genes affecting meiotic progression, DNA condensation and Gurken signaling. 118 new ventralizing mutants on the second chromosome fell into 17 complementation groups. Here we describe the analysis of eight complementation groups, including Kinesin heavy chain, the SR protein kinase cuaba, the cohesin-related gene dPds5/cohiba and the Tudor domain gene montecristo. Our findings challenge the hypothesis that checkpoint activation upon persistent DSBs is exclusively mediated by ATR/Mei-41 kinase and instead reveals a more complex network of interactions that link DSB formation, checkpoint activation, meiotic delay, DNA condensation and Gurken protein synthesis.

Lymphocyte transformation induced by Theileria parasites involves constitutive activation of c-Jun N-terminal kinase (JNK) and the AP-1 transcription factor. We found that JNK/AP-1 activation is associated with elevated levels of Rab11 protein in Theileria-transformed B cells. We show that AP-1 regulates rab11a promoter activity in B cells and that the induction of c-Jun activity in mouse fibroblasts also leads to increased transcription of the endogenous rab11a gene, consistent with it being an AP-1 target. Pharmacological inhibition of the JNK pathway reduced Rab11 protein levels and endosome recycling of transferrin receptor (TfR) and siRNA knockdown of JNK1 and Rab11A levels also reduced TfR surface expression. We propose a model, where activation of the JNK/AP-1 pathway during cell transformation might assure that the regulation of recycling endosomes is co-ordinated with cell-cycle progression. This might be achieved via the simultaneous upregulation of the cell cycle machinery (e.g. cyclin D1) and the recycling endosome regulators (e.g. Rab11A).

Heavy metal pollution still represents a primary concern regarding human health. Recently, it become evident that the contribution of heavy metals extends far beyond their accepted role in allergic diseases, and that they may play a more extensive role in a variety of other diseases. Several lines of evidence indicate that heavy metals have a key role in the induction or exacerbation of several autoimmune diseases (AD). Moreover, the association between exposure to heavy metals and the signs of autoimmunity are supported by some studies. The mechanisms by which heavy metals induce the development of AD are not yet fully understood. Our objective here is to highlight the association of exposure to some heavy metals and AD. In addition, we present recent results showing the possible alterations in Th1/Th2 reactivity by some heavy metals, which may constitute the trigger for the incidence of autoimmunity in susceptible individuals.

The pathophysiology of diabetic wound healing and the identification of new agents to improve clinical outcomes continue to be areas of intense research. There currently exist more than 10 different murine models of diabetes. The degree to which wound healing is impaired in these different mouse models has never been directly compared. We determined whether differences in wound impairment exist between diabetic models in order to elucidate which model would be the best to evaluate new treatment strategies. Three well-accepted mouse models of diabetes were used in this study: db/db, Akita, and streptozocin (STZ)-induced C57BL/6J. Using an excisional model of wound healing, we demonstrated that db/db mice exhibit severe impairments in wound healing compared with STZ and Akita mice. Excisional wounds in db/db mice show a statistically significant delay in wound closure, decreased granulation tissue formation, decreased wound bed vascularity, and markedly diminished proliferation compared with STZ, Akita, and control mice. There was no difference in the rate of epithelialization of the full-thickness wounds between the diabetic or control mice. Our results suggest that splinted db/db mice may be the most appropriate model for studying diabetic wound-healing interventions as they demonstrate the most significant impairment in wound healing. This study utilized a novel model of wound healing developed in our laboratory that stents wounds open using silicone splints to minimize the effects of wound contraction. As such, it was not possible to directly compare the results of this study with other studies that did not use this wound model

The composition of zymogen granules from rat pancreas was determined by LC-MS/MS. Enriched intragranular content, peripheral membrane, and integral membrane protein fractions were analyzed after one-dimensional SDS-PAGE and tryptic digestion of gel slices. A total of 371 proteins was identified with high confidence, including 84 previously identified granule proteins. The 287 remaining proteins included 37 GTP-binding proteins and effectors, 8 tetraspan membrane proteins, and 22 channels and transporters. Seven proteins, pantophysin, cyclic nucleotide phosphodiesterase, carboxypeptidase D, ecto-nucleotide phosphodiesterase 3, aminopeptidase N, ral, and the potassium channel TWIK-2, were confirmed by immunofluorescence microscopy or by immunoblotting to be new zymogen granule membrane proteins. Keywords: proteomics * mass spectrometry * LC-MS/MS * pancreas * zymogen granules * acinar cells.

BACKGROUND: Surgical resection of isolated hepatic or pulmonary colorectal metastases prolongs survival in selected patients. But the benefits of resection and appropriate selection criteria in patients who develop both hepatic and pulmonary metastases are ill defined. STUDY DESIGN: Data were prospectively collected from 131 patients with colorectal cancer who underwent resection of both hepatic and pulmonary metastases over a 20-year period. Median followup was 6.6 years from the time of resection of the primary tumor. Patient, treatment, and outcomes variables were analyzed using log-rank, Cox regression, and Kaplan-Meier methods. RESULTS: The site of first metastasis was the liver in 65% of patients, the lung in 11%, and both simultaneously in 24%. Multiple hepatic metastases were present in 51% of patients, and multiple pulmonary metastases were found in 48%. Hepatic lobectomy or trisegmentectomy was required in 61% of patients; most lung metastases (80%) were treated with wedge excisions. Median survival rates from resection of the primary disease, first site of metastasis, and second site of metastasis were 6.9, 5.0, and 3.3 years, respectively. After resection of disease at the second site of metastasis, the 1-, 3-, 5-, and 10-year disease-specific survival rates were 91%, 55%, 31%, and 19%, respectively. An analysis of prognostic factors revealed that survival was significantly longer when the disease-free interval between the development of the first and second sites of metastases exceeded 1 year, in patients with a single liver metastasis, and in patients younger than 55 years old. CONCLUSIONS: Surgical resection of both hepatic and pulmonary colorectal metastases is associated with prolonged survival in selected patients. Patients with a longer disease-free interval between metastases and those with single liver lesions had the best outcomes