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We report a prostate cancer genome-wide association follow-on study. We discovered four variants associated with susceptibility to prostate cancer in several European populations: rs10934853[A] (OR = 1.12, P = 2.9 x 10(-10)) on 3q21.3; two moderately correlated (r2 = 0.07) variants, rs16902094[G] (OR = 1.21, P = 6.2 x 10(-15)) and rs445114[T] (OR = 1.14, P = 4.7 x 10(-10)), on 8q24.21; and rs8102476[C] (OR = 1.12, P = 1.6 x 10(-11)) on 19q13.2. We also refined a previous association signal on 11q13 with the SNP rs11228565[A] (OR = 1.23, P = 6.7 x 10(-12)). In a multivariate analysis using 22 prostate cancer risk variants typed in the Icelandic population, we estimated that carriers in the top 1.3% of the risk distribution are at a 2.5 times greater risk of developing the disease than members of the general population.

Background: Recent whole genome association studies have independently identified multiple prostate cancer (PC) risk variants on 8q24. We have evaluated association of common variants in this region with PC susceptibility and tumor aggressiveness in a sample of European American men., Methods: Forty-nine tagging SNPs including three previously reported significant variants (rs1447295, rs6983267, rs16901979) and seven variants in the 5' upstream region of the MYC proto-oncogene were tested for association with susceptibility to PC and tumor aggressiveness in 596 histologically verified PC cases and 567 ethnically matched controls., Results: Significant associations with susceptibility to PC were found at 17 SNPs, four of which (rs1016342, rs1378897, rs871135, and rs6470517) remained significant after adjusting for multiple corrections. One of the associated SNPs, rs871135, is located in the putative gene POU5F1P1 within the 8q24 region. An in slico analysis showed that the associated variant of this SNP alters a transcription factor implicating a plausible regulatory role. Additionally, one of the significantly associated SNPs, rs6470517, with PC susceptibility showed a significant over-representation of the G allele in cases with aggressive tumor., Conclusions: Although this study does not directly confirm associations of the three specific SNPs (cited above), it corroborates reported signals of association in 8q24 reaffirming that genetic variation on 8q24 influences susceptibility to PC in men of European ancestry. Although our study did not confirm the allelic association of rs1447295, meta-analysis of this SNP provided support to previous reported associations. Further, this study implicates the 8q24 region with aggressive forms of PC.

Objective: To compare the outcomes between patients with stage T1a/b with those of patients with T1c cancer of the prostate treated with radical retropubic prostatectomy (RRP), as the appropriate management of clinical stage T1a/b prostate cancer is subject to debate; although many patients are managed expectantly, some have adverse pathological features suggesting that more active treatment might be beneficial., Patients and Methods: From 1983 to 2003, 3478 men had RRP by one surgeon. From this group, we retrospectively identified 29 men with clinical stage T1a and 83 with clinical stage T1b disease. Using statistical analysis we compared the treatment outcomes of these patients with those of 1774 men with clinical stage T1c disease., Results: Men with T1a/b disease had a significantly lower preoperative prostate-specific antigen (PSA) level, a greater proportion with organ-confined disease, and a lower mean/median prostatectomy Gleason score than those with T1c disease. Also, men with T1a/b disease were less likely to be potent before surgery, although the frequency of recovery of potency was similar among all groups. On multivariate analysis with age, year of surgery, PSA level and Gleason score, there was no statistical difference in the rates of biochemical recurrence and the 10-year overall survival rates. However, patients with T1b disease had a significantly lower cancer-specific survival., Conclusions: T1a and T1b prostate cancer can be associated with aggressive pathological features and have a similar rate of progression as clinical stage T1c disease. That notwithstanding, most patients in the study were cured with RRP and had favourable long-term functional outcomes.

Objectives: To determine whether prostate-specific antigen (PSA) values can distinguish those with prostate cancer (CaP) from those with histologic benign prostatic hyperplasia (BPH) only after surgical intervention. Prostatic adenoma inevitably remains after BPH surgery; therefore, patients remain at risk of developing CaP. Although the PSA level can be used for CaP screening in this population, it might be influenced by the efficacies of different BPH procedures., Methods: We performed a review of patients who had undergone transurethral resection of the prostate (TURP; n = 343), holmium laser resection of the prostate (HoLRP; n = 54), or open prostatectomy (OP; n = 68). The PSA and PSA velocity values were collected at regular intervals both pre- and postoperatively for all patients. Only patients with histologic BPH and those with incidental CaP who underwent a watchful waiting strategy were included., Results: The average preoperative PSA values were significantly different between the TURP, HoLRP, and OP groups. Only 1 patient had incidental CaP in the HoLRP group. No differences were present between the preoperative PSA values for patients with histologic BPH and those with incidental CaP undergoing a watchful waiting strategy (P > .05). However, the postoperative PSA values were increased in the patients with CaP (watchful waiting compared with the patient with BPH only (2.4 vs 1.7 ng/mL TURP and 4.1 vs 1.1 ng/mL OP). Similarly, patients with incidental CaP had a significantly elevated postoperative mean PSA velocity compared with patients without CaP (0.38 vs 0.06 ng/mL/y TURP and 0.47 vs -0.13 ng/mL/y OP; P < .05)., Conclusions: Postoperative PSA and PSA velocity measurements can be used to distinguish patients with CaP from those with histologic BPH only.

Purpose: The Prostate Cancer Prevention Trial reported that 15% of men with a prostate specific antigen less than 4 ng/ml and a normal digital rectal examination have biopsy detectable prostate cancer. However, limited published data describe the tumor features of prostate cancer detected at low prostate specific antigen levels (less than 2.5 ng/ml)., Materials and Methods: A total of 1,278 men underwent radical retropubic prostatectomy by 1 surgeon between 2003 and 2008. We describe the clinicopathological features of 77 patients with a preoperative prostate specific antigen of less than 2.5 ng/ml., Results: Of the men with a low prostate specific antigen (less than 2.5 ng/ml) tumor 51 (66%) had findings suspicious for prostate cancer on digital rectal examination. Indications for prostate biopsy in the remainder of men included an increased prostate specific antigen velocity, hematospermia and abnormal transrectal ultrasound findings. Prostate cancer was detected at transurethral resection of the prostate in the remaining 8% of men. Despite having a low prostate specific antigen at diagnosis 8 (10.4%) and 20 (26%) men, respectively, had biopsy and radical retropubic prostatectomy Gleason grade 7 disease or greater, while 7 (9%) and 6 (7.8%), respectively, had extracapsular tumor extension or positive surgical margins. Compared to men with a normal digital rectal examination mean tumor volume was significantly higher in those with a suspicious digital rectal examination (3.3 vs 1.7 cc, p = 0.018)., Conclusions: Despite having a prostate specific antigen of less than 2.5 ng/ml at diagnosis, a considerable proportion of men had aggressive pathological features at radical retropubic prostatectomy. Digital rectal examination remains an important component of early prostate cancer detection.

Purpose: The primary responsibility of institutional review boards is to protect human research subjects and, therefore, ensure that studies are performed in accordance with a standard set of ethical principles. A number of groups have compared the responses of institutional review boards in multicenter clinical trials involving medical therapies. To our knowledge no such studies have been performed to date of trials investigating surgical intervention. We investigated the consistency of the recommendations issued by various institutional review boards in the Minimally Invasive Surgical Therapies study for benign prostatic hyperplasia, a multicenter trial with a uniform consent and study protocol., Materials and Methods: We obtained the institutional review board response from 6 of the 7 participating institutions after initial submission of the Minimally Invasive Surgical Therapies study protocol and classified the responses. We then redistributed the approved protocols to an institutional review board at another participating institution and analyzed that review of these protocols., Results: We found that the number and type of responses required for institutional review board approval of an identical study protocol varied significantly among participating institutions. We also found that institutional review board responses were inconsistent in the second review, although all protocols were ultimately approved., Conclusions: The current system of local institutional review board review in the context of a multicenter surgical trial is inefficient in the review process and may not provide expertise for overseeing surgical trials. Based on these results a central surgical institutional review board may be needed to improve the ethical review process in multicenter trials.

Purpose: Recent studies have identified 2 distinct genetic variants along chromosome 17, including allele T of single nucleotide polymorphism rs4430796 on 17q12 and allele G of single nucleotide polymorphism rs1859962 on 17q24, that have been linked to prostate cancer risk. Less is known about tumor pathological features in carriers of these variants., Materials and Methods: Genotypes for regions 17q12 and 17q24 were determined in 759 white men with prostate cancer and compared to those in 790 healthy control volunteers using logistic regression. In patients with prostate cancer the Fisher exact or Kruskal-Wallis test was used as appropriate to assess the relationship(s) between clinical and pathological characteristics with 17q carrier status., Results: The frequency of the 17q12 and 17q24 genetic variants was significantly higher in patients with prostate cancer compared to that in controls (OR 1.32, 1.15, respectively). Of patients with prostate cancer 83% and 77% were carriers of the 17q12 and 17q24 variants as well as 75% and 75% of controls, respectively. Carriers of 17q12 risk variants were significantly more likely to have high grade disease using an additive best fit genetic model. In addition, there were trends toward adverse pathological features associated with 17q12 independent of the best fit genetic model., Conclusions: Sequence variants along 17q12 and 17q24 were present in a significantly higher proportion of our prostate cancer cases than in our controls. Adverse pathological features, including higher Gleason grade and pathological stage, were more frequent in 17q12 carriers. Since these alleles may act in conjunction with variants on other chromosomes to influence prostate cancer risk, additional research is required to determine the cumulative associations of genetic risk variants with prognosis.

Purpose: Transforming growth factor-beta (TGF-beta)-mediated epithelial-to-mesenchymal transition (EMT) has been shown to occur in some cancers; however, the pathway remains controversial and varies with different cancers. In addition, the mechanisms by which TGF-beta and the EMT contribute to prostate cancer recurrence are largely unknown. In this study, we elucidated TGF-beta-mediated EMT as a predictor of disease recurrence after therapy for prostate cancer, which has not been reported before., Experimental Design: We analyzed TGF-beta-induced EMT using nuclear factor-kappaB (NF-kappaB) as an intermediate mediator in prostate cancer cell lines. A total of 287 radical prostatectomy specimens were evaluated using immunohistochemistry in a high-throughput tissue microarray analysis. Levels of TGF-beta signaling components and EMT-related factors were analyzed using specific antibodies. Results were expressed as the percentage of cancer cells that stained positive for a given antibody and were correlated with disease recurrence rates at a mean of 7 years following radical prostatectomy., Results: In prostate cancer cell lines, TGF-beta-induced EMT was mediated by NF-kappaB signaling. Blockade of NF-kappaB or TGF-beta signaling resulted in abrogation of vimentin expression and inhibition of the invasive capability of these cells. There was high risk of biochemical recurrence associated with tumors that displayed high levels of expression of TGF-beta1, vimentin, and NF-kappaB and low level of cytokeratin 18. This was particularly true for vimentin, which is independent of patients' Gleason score., Conclusions: The detection of NF-kappaB-mediated TGF-beta-induced EMT in primary tumors predicts disease recurrence in prostate cancer patients following radical prostatectomy. The changes in TGF-beta signaling and EMT-related factors provide novel molecular markers that may predict prostate cancer outcomes following treatment.

Transvaginal ultrasound-guided oocyte retrieval is generally a safe and well-tolerated procedure that is usually associated with few overall complications (less than 5%), including mild vaginal hemorrhage and infection. Injury to the ureter during oocyte retrieval has only been reported in 6 cases to date. We report a case of ureterovaginal fistula that formed approximately 7 days after oocyte retrieval. A percutaneous nephrostomy tube was placed using ultrasound guidance, and the fistula was allowed to close secondarily. Although a rare complication, physicians should be conscious of this type of injury after oocyte retrieval so that prompt diagnosis and treatment can be pursued.

Objective: To describe the surgical outcomes and operative technique for reconstructing catheter-induced urethral erosion in men with a neurogenic bladder., Patients and Methods: This was a prospective study of 11 men (median age 45 years, range 26-52) who had elective urethroplasty for urethral erosion between 2004 and 2007 by one surgeon (C.M.G.). All men had a diagnosis of neurogenic bladder and indwelling catheter-induced urethral erosion. Reconstructive techniques included primary closure in six men, substitution urethroplasty with a penile skin graft in three, penile skin flap in one and a buccal mucosa graft in one. A two-stage approach was used in one man., Results: The median (range) length of erosion from the meatus before surgery was 6 (4-10) cm. The repair was successful in seven men at a mean (range) follow-up of 25 (8-46) months. Of those with recurrence of erosion, the median length of the resultant defect was 2 (2-3) cm. All recurrences were in the first five patients of this series. The median time to recurrence of erosion was 1 month and recurrence did not appear to be related to any particular surgical technique. Urethral catheter traction after surgery appeared to be one of the factors related to repair breakdown., Conclusion: The reconstruction of catheter-induced urethral erosion in men with a neurogenic bladder is feasible. Primary closure appears to be the best reconstructive method for urethral erosion, and avoiding catheter traction after surgery contributes to successful urethroplasty.

Suprapubic tube placement is a common urological procedure with a low incidence of complications, including hematuria, catheter blockage, recurrent urinary tract infections, and rarely, injury to adjacent organs. Fortunately, most serious complications are discovered shortly after initial suprapubic tube placement and are readily corrected. Very few cases of delayed complications or injuries have been reported. We report a case of Foley perforation into the ileum during suprapubic tube exchange discovered more than 8 months after initial placement, and preceding numerous monthly changes that occurred without incident. While a rare complication, physicians should be conscious of the potential for delayed injury in patients managed with long term suprapubic tube placement.

Objective: To compare the outcomes of patients presenting with and without acute urinary retention (AUR) who were treated with 100-W holmium laser resection of the prostate (HoLRP), as laser therapies, including HoLRP, have been used for treating lower urinary tract symptoms secondary to benign prostatic hyperplasia (BPH), but the effectiveness of HoLRP for patients with AUR has not been fully elucidated., Patients and Methods: The medical records of 87 patients who had HoLRP were reviewed, and prospective questionnaires aimed at determining patients' American Urologic Association Symptom Index (AUA-SI) and Quality-of-Life (QoL) scores and medication usage were also obtained. Statistical analyses were used to compare the clinical characteristics and outcomes between patients with and with no AUR for up to 2 years after HoLRP., Results: All patients had the catheter removed successfully by 1 month after surgery; those presenting with AUR tended to have a greater improvement in clinical outcomes than those with no AUR, including a mean AUA-SI score decrease by approximately 13 and approximately 8 points, and a QoL score decrease by approximately 2 and approximately 1.4 points, respectively. These decreases were maintained throughout the study period. Patients with AUR had significantly greater decreases in their postvoid residual urine volume than those with no AUR. Serum prostate-specific antigen levels also had a modest but sustained decrease (14%) in both groups. There were no significant decreases in the reported use of BPH-related medications after surgery in either group., Conclusions: HoLRP (100 W) is a safe and effective surgical therapy for patients presenting with AUR. The present results suggest that the short- and long-term outcomes of these patients are similar between men presenting with and with no AUR.

Objectives: With the widespread use of prostate-specific antigen (PSA)-based screening, there is now concern about the overdiagnosis and overtreatment of men with low-risk prostate cancer (PCa). One of the most difficult aspects of PCa management is a balance of the often-competing goals of cancer control with functional outcomes and quality of life. To address this issue, we examined the potency, continence and overall complication rates associated with radical prostatectomy (RP), specifically in potential candidates for active monitoring., Methods: From a large RP database, we compared potency, continence, and complication rates among men meeting one of the following active monitoring criteria from the literature: clinically localized, Gleason score of 7 or less, and no significant comorbidities; T1b-T2b NOMO, Gleason score of 7 or less, and PSA of 15 ng/mL or less; and T1c PCa., Results: There were 3458, 3533, and 2338 men who met the above criteria, respectively. After 18 months of follow-up, potency was preserved in 70% to 74%. At least 93% of patients were continent, and the rate of surgical complications ranged from 5% to 7%. Increasing age was significantly associated with a greater risk of all complications., Conclusions: Men with newly diagnosed low-risk PCa must carefully weigh the risks and benefits of treatment. In young men with low-risk PCa, RP was associated with a relatively low complication rate and good long-term functional outcomes. However, with increasing age, RP was associated with significantly higher complication rates. These results can be used to help guide management decisions for men with low-risk disease.

Purpose: In collaboration with deCODE Genetics Inc. we previously reported on the association between genetic variants on chromosome 8q24 and prostate cancer susceptibility. Several prior studies have examined the relationship between these 8q24 alleles and clinical tumor features. In this study we examine the differences in clinical and pathological tumor features between carriers and noncarriers of these 8q24 alleles in patients with prostate cancer., Materials and Methods: We genotyped 551 white men who underwent radical prostatectomy or radiation therapy for clinically localized prostate cancer at single institution between 2002 and 2005. Of these men 177 (32.1%) were carriers of the -8 allele of the microsatellite marker DG8S737, the A allele of the single nucleotide polymorphism rs1447295 and/or the A allele of the rs16901979 (a surrogate single nucleotide polymorphism of HapC) 8q24 alleles. We used statistical analyses to compare the distribution of clinical characteristics and pathological outcomes between carriers and noncarriers., Results: The -8, A and HapC surrogate single nucleotide polymorphism alleles were present in 77 (14%), 128 (23%) and 61 (14%) patients with prostate cancer, respectively. Carriers of the -8 or multiple 8q24 alleles were significantly more likely to have a Gleason score of 7 or greater and lymph node metastases. Among men with a family history of prostate cancer, carriers of the -8 allele had a significantly greater risk of high grade disease (64% vs 39%, p = 0.04)., Conclusions: In our predominantly surgically treated population there was a significant association between 8q24 prostate cancer susceptibility alleles, particularly the -8 allele, and high grade disease. In men with a family history of prostate cancer the presence of 1 or more of these alleles also conferred a greater risk of some adverse pathological features.

Purpose: Retrieval of a proximally migrated ureteral stent is a technically challenging endoscopic procedure. We describe the use of a paired wire helical stone retrieval basket through a flexible ureteroscope to remove proximally migrated ureteral stents., Materials and Methods: Five ureteral stents were lost in the proximal (1) and distal (4) ureter after lithotripsy or stent exchange. Once the location of the distal aspect of the ureteral stent was identified by either fluoroscopy or ureteroscopy, a safety guidewire was placed alongside the migrated stent. A flexible ureteroscope was brought to the distal end of the stent under direct visualization. Through the working port of the ureteroscope, the paired wire helical basket was deployed to grasp or coaxially cannulate the lumen of the migrated stent. Once inside the stent, the basket was then opened. The outward resistance of the deployed basket is sufficient to provide enough lateral force to reposition the stent into the bladder., Results: All stents were successfully retrieved without complication. No patient had visual evidence of ureteral injury, and all patients were discharged on the same day as their procedure., Conclusion: While proximal migration of a ureteral stent is usually caused by technical error, the ideal technique to reposition the stent should require the least time, trauma to the ureter, and expense to the patient. We describe a simple technique to retrieve migrated stents anywhere along the urinary tract.

Purpose: Despite the tremendous stage migration associated with prostate cancer screening to our knowledge it remains unproven whether prostate specific antigen based screening decreases prostate cancer specific mortality. Recent studies have shown that prostate specific antigen velocity more than 2 ng/ml per year in the year before diagnosis is associated with a significantly greater risk of prostate cancer specific mortality after treatment. This may serve as a surrogate marker for prostate cancer outcomes. We compared the prostate specific antigen velocity profile between patients with prostate cancer in whom the tumor was detected in a formal screening study and those who were referred for treatment., Materials and Methods: We evaluated prostate specific antigen velocity in 1,101 men from a prostate cancer screening study and in 368 not enrolled in a screening study who were referred for treatment. All patients underwent radical prostatectomy for clinically localized disease and had multiple preoperative prostate specific antigen measurements to calculate prostate specific antigen velocity., Results: Median prostate specific antigen velocity before diagnosis was significantly higher in referred vs screened men (1.35 vs 0.68 ng/ml per year, p <0.0001). In addition, a significantly greater proportion of referred patients had prostate specific antigen velocity more than 2 ng/ml per year (38% vs 17%, p <0.0001). On multivariate analysis using prostate specific antigen, clinical stage and biopsy Gleason score screened vs referred status was a significant independent predictor of prostate specific antigen velocity more than 2 ng/ml per year (p <0.0004)., Conclusions: Prostate specific antigen velocity more than 2 ng/ml per year has been linked to a significantly greater risk of prostate cancer specific mortality. Patients who underwent serial screening had a more favorable prostate specific antigen velocity profile at diagnosis, suggesting that screen detected prostate cancer may be more likely to be cured with definitive therapy.

We conducted a genome-wide SNP association study on prostate cancer on over 23,000 Icelanders, followed by a replication study including over 15,500 individuals from Europe and the United States. Two newly identified variants were shown to be associated with prostate cancer: rs5945572 on Xp11.22 and rs721048 on 2p15 (odds ratios (OR) = 1.23 and 1.15; P = 3.9 x 10(-13) and 7.7 x 10(-9), respectively). The 2p15 variant shows a significantly stronger association with more aggressive, rather than less aggressive, forms of the disease.

How timely transport of chemical signals between the distal end of long axonal processes and the cell bodies of neurons occurs is an interesting and unresolved issue. Recently, Perlson et al. presented evidence that cleavage products of newly synthesized vimentin, an intermediate filament (IF) protein, interact with mitogen-activated protein (MAP) kinases at sites of axon injury. These IF fragments appear to be required for the transport of these kinases to the cell body along microtubule tracks. The truncated vimentin is instrumental in signal propagation as it provides a scaffold that brings together activated MAP kinases (such as Erk 1 and Erk2), as well as importin beta and cytoplasmic dynein. The authors propose that this all-in-one transport complex has the extraordinary ability to travel towards the cell body and enter the nucleus where the kinases activate and influence gene expression so that a neuron can generate a timely response to injury.

Recent evidence showing that intermediate filaments (IFs) are dynamic, motile elements of the cytoskeletal repertoire of vertebrate cells has overturned the long-standing view that they simply form static 'space filling' cytoplasmic networks. In fact, many types of IF are now known to engage in a remarkable array of movements that are closely associated with their assembly, disassembly and subcellular organization. Some of these motile properties are intrinsic to IFs and others are attributable to molecular crosstalk with either microtubules or actin-containing microfilaments. This crosstalk is, to a large extent, mediated by molecular motors, including conventional kinesin and cytoplasmic dynein. These motors are responsible for the high-speed delivery of nonfilamentous IF precursors and short filaments to specific regions of the cytoplasm, where they assemble into long IFs. Interestingly, the patterns and speeds of IF movements vary in different cell types and even within different regions of the same cell. These differences in motility may be related to their interactions with different types of molecular motor and/or other factors, such as IF-associated proteins.

To date, the functions of most neural intermediate filament (IF) proteins have remained elusive. Peripherin is a type III intermediate filament (IF) protein that is expressed in developing and in differentiated neurons of the peripheral and enteric nervous systems. It is also the major IF protein expressed in PC12 cells, a widely used model for studies of peripheral neurons. Dramatic increases in peripherin expression have been shown to coincide with the initiation and outgrowth of axons during development and regeneration, suggesting that peripherin plays an important role in axon formation. Recently, small interfering RNAs (siRNA) have provided efficient ways to deplete specific proteins within mammalian cells. In this study, it has been found that peripherin-siRNA depletes peripherin and inhibits the initiation, extension, and maintenance of neurites in PC12 cells. Furthermore, the results of these experiments demonstrate that peripherin IF are critical determinants of the overall shape and architecture of neurons.

Promiscuous small molecules plague screening libraries and hit lists. Previous work has found that several nonspecific compounds form submicrometer aggregates, and it has been suggested that this aggregate species is responsible for the inhibition of many different enzymes. It is not understood how aggregates inhibit their targets. To address this question, biophysical, kinetic, and microscopy methods were used to study the interaction of promiscuous, aggregate-forming inhibitors with model proteins. By use of centrifugation and gel electrophoresis, aggregates and protein were found to directly interact. This is consistent with a subsequent observation from confocal fluorescence microscopy that aggregates concentrate green fluorescent protein. beta-Lactamase mutants with increased or decreased thermodynamic stability relative to wild-type enzyme were equally inhibited by an aggregate-forming compound, suggesting that denaturation by unfolding was not the primary mechanism of interaction. Instead, visualization by electron microscopy revealed that enzyme associates with the surface of inhibitor aggregates. This association could be reversed or prevented by the addition of Triton X-100. These observations suggest that the aggregates formed by promiscuous compounds reversibly sequester enzyme, resulting in apparent inhibition. They also suggest a simple method to identify or reverse the action of aggregate-based inhibitors, which appear to be widespread.

Peripherin is a neural intermediate filament protein that is expressed in peripheral and enteric neurons, as well as in PC12 cells. A determination of the motile properties of peripherin has been undertaken in PC12 cells during different stages of neurite outgrowth. The results reveal that non-filamentous, non-membrane bound peripherin particles and short peripherin intermediate filaments, termed 'squiggles', are transported at high speed throughout PC12 cell bodies, neurites and growth cones. These movements are bi-directional, and the majority require microtubules along with their associated molecular motors, conventional kinesin and cytoplasmic dynein. Our data demonstrate that peripherin particles and squiggles can move as components of a rapid transport system capable of delivering cytoskeletal subunits to the most distal regions of neurites over relatively short time periods.

For many years, cytoplasmic intermediate filaments (IFs) were considered to be stable cytoskeletal elements contributing primarily to the maintenance of the structural and mechanical integrity of cells. However, recent studies of living cells have revealed that IFs and their precursors possess a remarkably wide array of dynamic and motile properties. These properties are in large part due to interactions with molecular motors such as conventional kinesin, cytoplasmic dynein, and myosin. The association between IFs and motors appears to account for much of the well-documented molecular cross talk between IFs and the other major cytoskeletal elements, microtubules, and actin-containing microfilaments. Furthermore, the associations with molecular motors are also responsible for the high-speed, targeted delivery of nonfilamentous IF protein cargo to specific regions of the cytoplasm where they polymerize into IFs. This review considers the functional implications of the motile properties of IFs and discusses the potential relationships between malfunctions in these motile activities and human diseases.

We present evidence that vimentin intermediate filament (IF) motility in vivo is associated with cytoplasmic dynein. Immunofluorescence reveals that subunits of dynein and dynactin are associated with all structural forms of vimentin in baby hamster kidney-21 cells. This relationship is also supported by the presence of numerous components of dynein and dynactin in IF-enriched cytoskeletal preparations. Overexpression of dynamitin biases IF motility toward the cell surface, leading to a perinuclear clearance of IFs and their redistribution to the cell surface. IF-enriched cytoskeletal preparations from dynamitin-overexpressing cells contain decreased amounts of dynein, actin-related protein-1, and p150Glued relative to controls. In contrast, the amount of dynamitin is unaltered in these preparations, indicating that it is involved in linking vimentin cargo to dynactin. The results demonstrate that dynein and dynactin are required for the normal organization of vimentin IF networks in vivo. These results together with those of previous studies also suggest that a balance among the microtubule (MT) minus and plus end-directed motors, cytoplasmic dynein, and kinesin are required for the assembly and maintenance of type III IF networks in interphase cells. Furthermore, these motors are to a large extent responsible for the long recognized relationships between vimentin IFs and MTs.

Until recently, the dynamic properties of intermediate filaments (IF) were attributed primarily to the exchange of subunits between a disassembled pool and polymerized 10nm filaments. During interphase, this subunit exchange process was thought to produce local modifications in IF structure. During cell division, shifts in the equilibrium between subunits and polymers were thought to lead to either the global or regional disassembly of IF networks, thereby facilitating their distribution into daughter cells. Recently, novel structural forms of IF that undergo rapid and directed transport in several cell types were revealed. Time-lapse observations of motile IF structures in different cell systems have also revealed novel insights into the mechanisms underlying the transport of cytoskeletal components throughout the cytoplasm and the molecular basis of the 'crosstalk' between different cytoskeletal systems.

Using squid axoplasm as a model system, we have visualized the fast transport of non-filamentous neurofilament protein particles along axonal microtubules. This transport occurs at speeds of 0.5-1.0 microm/second and the majority of neurofilament particles stain with kinesin antibody. These observations demonstrate, for the first time, that fast (0.5-1.0 microm/second) transport of neurofilament proteins occurs along microtubules. In addition, our studies suggest that neurofilament protein can be transported as non-membrane bound, nonfilamentous subunits along axons, and that the transport is kinesin-dependent. Microtubule-based fast transport might therefore provide a mechanism for the distribution and turnover of neurofilament, and perhaps other cytoskeletal proteins, throughout neurons.

>Objective: Administration of purified human IgG from antiphospholipid syndrome patients has not consistently caused murine pregnancy loss despite the presence of significant anticardiolipin antibody (ACA) activity. We evaluated whether a correlation exists between ACA activity and the degree of fetal resorption in murine pregnancy and also determined whether pooled IgG from multiple ACA-positive patients increases the likelihood of fetal resorption compared with injection of single-donor IgG.Methods: Affinity chromatography followed by anisotropic ultrafiltration was used to extract and concentrate IgG from individual serum samples with and without ACA activity (ACA-positive IgG activity, 35-85 GPL versus ACA-negative IgG activity, <1 GPL) and from pooled aliquots derived from the same sera. On Day 8 of gestation, pregnant mice randomly received intraperitoneal injections of ACA-positive or ACA-negative, purified IgG (15 mg/mouse) or saline (1 ml). Laparotomies were performed on day 15, and uteri were harvested for gross evaluation and histologic study. Rates of fetal resorption were derived for each murine pregnancy (resorbed fetuses/resorbed fetuses + live pups) and compared between experimental groups.Results: A significant increase in fetal resorption rate was observed in ACA-positive IgG-treated animals (n = 19, 19.3%) compared with either ACA-negative (n = 5, 6.4%; P = 0.008) or saline-treated pregnancies (n = 8, 4.6%; P = 0.004). However, differences in resorption rates among the ACA-positive IgG-treated pregnancies did not correlate with initial ACA activity of the whole serum or with antibody activity measured in the purified, concentrated IgG preparations. A comparison of fetal resorption between single donor ACA-positive IgG and pooled ACA-positive IgG revealed similar rates of fetal resorption (20.5 versus 17.9%, respectively) but a lower mean birth weight among non-resorbed pups in the single-donor IgG-treated pregnancies (340 versus 430 mg; P = 0.05).Conclusions: Although greater murine fetal resorption resulted from ACA-positive IgG administration compared with ACA-negative IgG or saline injection, marked variability in pregnancy outcome was observed among ACA-positive animals. These differences were not attributable to initial antibody activity in whole serum or to activity associated with the purified immunoglobulins. Combining multiple ACA-positive sera did not augment the rate of fetal resorption.

Objective: To compare pregnancy outcome in twin gestations resulting from multifetal reduction to "primary" twin pregnancies derived from either spontaneous conception or infertility therapy., Design: Case-control study., Setting: University-affiliated tertiary center., Patient(s): Multifetal pregnancies (quadruplets or more) reduced to twins (group A) compared with twin gestations conceived either spontaneously (group B) or through infertility therapy (group C)., Intervention(s): Multifetal reduction for group A; perinatal care for groups A, B, and C., Main Outcome Measure(s): Comparison of perinatal complications between groups including antepartum bleeding, premature membrane rupture, and preterm labor. Neonatal outcomes compared including gestational age at delivery, birth weight, incidence of fetal growth restriction, and twin discordancy., Result(s): A higher incidence of idiopathic preterm labor was noted in group A cases (14/18) compared with either of the control groups (B: 26/54, or C: 24/54). As a consequence, group A had the lowest gestational age at delivery (32.6 +/- 3.9 weeks) compared with groups B (33.6 +/- 4.4 weeks) and C (36.0 +/- 3.4 weeks). Corresponding birth weights of both first- and second-born twins were significantly lower in group A compared with group C, whereas the birth weight comparison between groups A and B showed a nonsignificant difference. The proportion of pregnancies in which one or both twins weighted less than the 10th percentile was greatest in group A pregnancies (A: 5/18 versus C: 5/54). Discordant birth weight among twin pairs was proportionately greater for group A cases at both the 20% and 30% discordance levels., Conclusion(s): Twin gestations resulting from multifetal reduction are at increased risk for preterm birth, fetal growth restriction, and discordancy when compared with fertility therapy-derived, nonreduced twins.