A Multisite Preregistered Paradigmatic Test of the Ego-Depletion Effect

We conducted a preregistered multilaboratory project (k = 36; N = 3,531) to assess the size and robustness of ego-depletion effects using a novel replication method, termed the paradigmatic replication approach. Each laboratory implemented one of two procedures that was intended to manipulate self-control and tested performance on a subsequent measure of self-control. Confirmatory tests found a nonsignificant result (d = 0.06). Confirmatory Bayesian meta-analyses using an informed-prior hypothesis (δ = 0.30, SD = 0.15) found that the data were 4 times more likely under the null than the alternative hypothesis. Hence, preregistered analyses did not find evidence for a depletion effect. Exploratory analyses on the full sample (i.e., ignoring exclusion criteria) found a statistically significant effect (d = 0.08); Bayesian analyses showed that the data were about equally likely under the null and informed-prior hypotheses. Exploratory moderator tests suggested that the depletion effect was larger for participants who reported more fatigue but was not moderated by trait self-control, willpower beliefs, or action orientation.

Identifying exceptional malaria occurrences in the absence of historical data in South Sudan: a method validation

Background

Detecting unusual malaria events that may require an operational intervention is challenging, especially in endemic contexts with continuous transmission such as South Sudan. Médecins Sans Frontières (MSF) utilises the classic average plus standard deviation (AV+SD) method for malaria surveillance. This and other available approaches, however, rely on antecedent data, which are often missing.

Objective

To investigate whether a method using linear regression (LR) over only 8 weeks of retrospective data could be an alternative to AV+SD.

Design

In the absence of complete historical malaria data from South Sudan, data from weekly influenza reports from 19 Norwegian counties (2006-2015) were used as a testing data set to compare the performance of the LR and the AV+SD methods. The moving epidemic method was used as the gold standard. Subsequently, the LR method was applied in a case study on malaria occurrence in MSF facilities in South Sudan (2010-2016) to identify malaria events that required a MSF response.

Results

For the Norwegian influenza data, LR and AV+SD methods did not perform differently (P > 0.05). For the South Sudanese malaria data, the LR method identified historical periods when an operational response was mounted.

Conclusion

The LR method seems a plausible alternative to the AV+SD method in situations where retrospective data are missing.

Muscle Derived Stem Cells Stimulate Muscle Myofiber Repair and Counteract Fat Infiltration in a Diabetic Mouse Model of Critical Limb Ischemia

Background

Critical Limb Ischemia (CLI) affects patients with Type 2 Diabetes (T2D) and obesity, with high risk of amputation and post-surgical mortality, and no effective medical treatment. Stem cell therapy, mainly with bone marrow mesenchymal, adipose derived, endothelial, hematopoietic, and umbilical cord stem cells, is promising in CLI mouse and rat models and is in clinical trials. Their general focus is on angiogenic repair, with no reports on the alleviation of necrosis, lipofibrosis, and myofiber regeneration in the ischemic muscle, or the use of Muscle Derived Stem Cells (MDSC) alone or in combination with pharmacological adjuvants, in the context of CLI in T2D.

Methods

Using a T2D mouse model of CLI induced by severe unilateral femoral artery ligation, we tested: a) the repair efficacy of MDSC implanted into the ischemic muscle and the effects of concurrent intraperitoneal administration of a nitric oxide generator, molsidomine; and b) whether MDSC may partially counteract their own repair effects by stimulating the expression of myostatin, the main lipofibrotic agent in the muscle and inhibitor of muscle mass.

Results

MDSC: a) reduced mortality, and b) in the ischemic muscle, increased stem cell number and myofiber central nuclei, reduced fat infiltration, myofibroblast number, and myofiber apoptosis, and increased smooth muscle and endothelial cells, as well as neurotrophic factors. The content of myosin heavy chain 2 (MHC-2) myofibers was not restored and collagen was increased, in association with myostatin overexpression. Supplementation of MDSC with molsidomine failed to stimulate the beneficial effects of MDSC, except for some reduction in myostatin overexpression. Molsidomine given alone was rather ineffective, except for inhibiting apoptosis and myostatin overexpression.

Conclusions

MDSC improved CLI muscle repair, but molsidomine did not stimulate this process. The combination of MDSC with anti-myostatin approaches should be explored to restore myofiber MHC composition.

Gold and Hydroxyapatite Nano-Composite Scaffolds for Anterior Cruciate Ligament Reconstruction: In Vitro Characterization

Current anterior cruciate ligament (ACL) graft replacement materials often fail due to the lack of biological integration. While many newly developed extracellular matrix based scaffolds show good biocompatibility they often do not entice cellular remodeling and the rebuilding of a functional ligament. We have proposed the conjugation of gold nanoparticles (AuNP) and hydroxyapatite nanoparticles (nano-HAp) to acellular tissue to enhance cell attachment and proliferation while maintaining an improved degradation resistance and open microstructure. We are the first to investigate the double conjugation of AuNP and nano-HAp onto decellularized tissue to improve the tissue remodeling response. Decellularized porcine diaphragm was crosslinked with two types of nano-HAp and amine-functionalized AuNP with 1-ethyl-3-(3-dimethlaminopropyl) carbodiimide (EDC) crosslinker. Scaffolds were characterized using electron microscopy, differential scanning calorimetry, and fibroblast assays. Results demonstrated that scaffolds with nano-HAp have increased thermal stability at low levels of crosslinking. The open microstructure of the scaffold was not compromised allowing for cell migration while still providing increased degradation resistance. The addition of < 200 nm nano-HAp decreased cell viability compared to scaffolds without nanoparticles, but the addition of AuNP to scaffolds showed enhanced cell viability in the presence of < 200 nm nano-HAp. The addition of < 40 nm nano-HAp showed an increase in cell viability compared to scaffolds crosslinked without nanoparticles. It is concluded that attaching AuNP and < 40nm nano-HAp to extracellular matrices may improve overall properties.

Perfluoroalkyl substances measured in breast milk and child neuropsychological development in a Norwegian birth cohort study

Perfluoroalkyl substances (PFASs) are chemicals with potential neurotoxic effects although the current evidence is still limited. This study investigated the association between perinatal exposure to perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) and neuropsychological development assessed at 6, 12 and 24 months. We measured PFOS and PFOA in breast milk samples collected one month after delivery by mothers of children participating in the HUMIS study (Norway). Cognitive and psychomotor development was measured at 6 and at 24 months using the Ages and Stages Questionnaire (ASQ-II). Behavioral development was assessed using the infant-toddler symptom checklist (ITSC) at 12 and at 24 months. Weighted logistic regression and weighted negative binomial regression models were applied to analyze the associations between PFASs and ASQ-II and ITSC, respectively. The median concentration of PFOS was 110 ng/L, while the median for PFOA was 40 ng/L. We did not detect an increased risk of having an abnormal score in ASQ-II at 6 months or 24 months. Moreover, no consistent increase in behavioral problems assessed at 12 and 24 months by ITSC questionnaire was detected. We observed no association between perinatal PFOS and PFOA exposure and early neuropsychological development. Further longitudinal studies are needed to confirm the effects of these compounds on neuropsychological development in older children.

Prevalence and causes of vision loss in Southeast Asia and Oceania: 1990-2010

BACKGROUND

To assess prevalence and causes of vision impairment in Southeast Asia and Oceania in 1990 and 2010.

METHODS

Based on a systematic review of medical literature, prevalence of moderate and severe vision impairment (MSVI; presenting visual acuity <6/18 but ≥3/60 in the better eye) and blindness (presenting visual acuity <3/60) was estimated for 1990 and 2010.

RESULTS

In Oceania, the age-standardised prevalence of blindness and MSVI did not decrease significantly (1.3% to 0.8% and 6.6% to 5.1%) respectively, but in Southeast Asia, blindness decreased significantly from 1.4% to 0.8%, a 43% decrease. There were significantly more women blind (2.18 million) compared with men (1.28 million) in the Southeast Asian population in 2010, but no significant gender differences in MSVI in either subregion. Cataract was the most frequent cause of blindness in Southeast Asia and Oceania in 1990 and 2010. Uncorrected refractive error, followed by cataract, macular degeneration, glaucoma and diabetic retinopathy were the most common causes for MSVI in 1990 and 2010. With the increasing size of the older population, there have been relatively small increases in the number of blind (2%), and with MSVI (14%) in Southeast Asia, whereas increases have been greater in Oceania of 14% for blindness and of 31% for MSVI.

CONCLUSIONS

The prevalence of blindness has reduced significantly from 1990 to 2010, with moderate but non-significant lowering of MSVI. Cataract and uncorrected refractive error are the main causes of vision impairment and blindness; cataract continues as the main cause of blindness, but at lower proportions.

WHO guidelines for the programmatic management of drug-resistant tuberculosis: 2011 update

The production of guidelines for the management of drug-resistant tuberculosis (TB) fits the mandate of the World Health Organization (WHO) to support countries in the reinforcement of patient care. WHO commissioned external reviews to summarise evidence on priority questions regarding case-finding, treatment regimens for multidrug-resistant TB (MDR-TB), monitoring the response to MDR-TB treatment, and models of care. A multidisciplinary expert panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to develop recommendations. The recommendations support the wider use of rapid drug susceptibility testing for isoniazid and rifampicin or rifampicin alone using molecular techniques. Monitoring by sputum culture is important for early detection of failure during treatment. Regimens lasting ≥ 20 months and containing pyrazinamide, a fluoroquinolone, a second-line injectable drug, ethionamide (or prothionamide), and either cycloserine or p-aminosalicylic acid are recommended. The guidelines promote the early use of antiretroviral agents for TB patients with HIV on second-line drug regimens. Systems that primarily employ ambulatory models of care are recommended over others based mainly on hospitalisation. Scientific and medical associations should promote the recommendations among practitioners and public health decision makers involved in MDR-TB care. Controlled trials are needed to improve the quality of existing evidence, particularly on the optimal composition and duration of MDR-TB treatment regimens.

Role of fluorescence in situ hybridization in sequencing the tomato genome

The tomato (Solanum lycopersicum L.) genome is being sequenced by a consortium of laboratories in 10 countries. Seventy-seven percent of the tomato genome (DNA) is located in repeat-rich, gene-poor, pericentric heterochromatin, while 23% of the genome is located in repeat-poor, gene-rich, distal euchromatin. It is estimated that approximately 90% of tomato's nuclear genes can be characterized by limiting the sequencing effort to euchromatin while avoiding the problems involved in sequencing the repetitive DNA in heterochromatin. Sequencing is being performed on tomato nuclear DNA cloned into bacterial artificial chromosome (BAC) vectors. Fluorescence in situ hybridization (FISH) is used to help direct the sequencing effort by cytologically demonstrating the location of selected BACs on tomato chromosomes. While mitotic metaphase chromosomes are too short and compact for this purpose, long pachytene chromosomes are ideal. BACs localized in euchromatin can be used confidently as anchors for the assembly of BAC contigs that extend through the euchromatic length of each chromosome arm. Another important role for FISH is identification of BACs near telomeres and near borders with pericentric heterochromatin to indicate that sequencing should not extend much further. This role of FISH is enhanced by our ability to estimate base pair distances between localized BACs and these chromosomal features. Finally, it is noteworthy that when BAC-FISH is combined with chromosomal in situ suppression (CISS) hybridization to block repeats and localize single/low copy sequences, the great majority of BACs localize to single sites. This observation is consistent with tomato being an ancient diploid.

Paleo-roothole facilitated transport of aromatic hydrocarbons through a Holocene clay bed

A field study involving high-resolution core sampling of a 0.5-2 m thick clay bed was undertaken at a contaminated former industrial facility in the UK to establish the nature and significance of preferential contaminant flowpaths. In contrast to most previous research, the focus was upon a buried aquitard, in this case a Holocene lagoonal clay located 6 m below ground surface and overlain by a sand aquifer impacted by historic nonaqueous phase liquid hydrocarbon spills. The study, involving 11 cores over a 630 by 150 m area, demonstrated that the presence of paleo- (i.e., preupper sand) rootholes controlled the degree of dissolved-phase benzene penetration into the aquitard. Where homogeneous, largely paleoroot-free clay is present (hydraulic conductivity 3 x 10(-5) m/d.), contaminant concentrations in the clay decline rapidly with depth: modeling showed the dominant transport process to be diffusion. In other cores, elevated benzene concentrations deep in the clay require advection to have occurred, presumably along preferential pathways. The latter were shown by thin sectioning, core slice mapping and 3-D X-ray tomography to be organic matter lined rootholes of < 2 mm aperture. The significance of such preferential pathways was confirmed quantitatively by measuring hydraulic conductivity (0.04 m/d) and calculating flux, the latter being over 10 times greater than expected from steady state diffusion. Our study hence demonstrates paleoenvironmental control of modern-day contaminant transport through a clay aquitard. It is suggested that many subaerial unconformities in mudrocks, especially those associated with even rudimentary paleosol development would lead to permeability enhancement and therefore afford substantially reduced protection against migrating contaminants. In contaminated site investigations, it is hence necessary to consider the aquitard paleoenvironment and not just the main rock type present.

Growth Characteristics of Calves Fed an Intensified Milk Replacer Regimen with Additional Lactoferrin

The objective of this study was to evaluate the effect of lactoferrin addition to milk replacer varying in crude protein (CP) on dry matter intake, growth, and days medicated. Thirty-four Holstein heifer calves were assigned to 4 treatments in a 2 x 2 factorial arrangement of treatments in a randomized complete block design. Treatments were as follows: 562 g daily of a nonmedicated conventional milk replacer (20% CP:20% fat) feeding regimen with or without 1 g of supplemental bovine lactoferrin (n = 9 for both treatments) or a nonmedicated intensified milk replacer feeding regimen (28% CP:20% fat) fed on a metabolizable energy basis (0.2 Mcal/kg BW(0.75)) from d 2 to 9, and at 0.27 Mcal/kg BW(0.75) from d 10 to 42 with or without 1g supplemental bovine lactoferrin (n = 8 for both treatments). Calves were fed pelleted starter (25% CP) in 227.5-g increments beginning on d 2 and had free access to water. Calves remained on the study for 14 d postweaning. Dry matter intake was determined daily. Growth measurements were taken weekly. Blood samples were taken twice weekly for determination of blood urea N. On d 10 of life, calves were subjected to a xylose challenge. Calves on conventional treatments ate more starter preweaning, during weaning, and postweaning. Preweaning, intensively fed calves had higher dry matter intakes. Weights of intensified-fed calves were greater at weaning. Intensified milk replacer-fed calves had greater average daily gain preweaning and overall and higher gain:feed ratios preweaning, but conventionally fed calves had higher gain:feed ratios during weaning. Intensified milk replacer-fed calves had greater hip heights during weaning and postweaning and greater heart girths preweaning, weaning, and postweaning. Days medicated were greater preweaning and overall for intensified-fed calves. There were no differences among treatments for xylose absorption. Calves on conventional treatments had increased blood urea nitrogen concentrations preweaning. There were no effects of lactoferrin on any experimental variable. Intensified milk replacer-fed calves consumed less starter but had higher average daily gains overall and larger frames and greater BW than conventionally fed calves. An intensified milk replacer feeding regimen promotes faster growth during the preweaning period when compared with calves fed conventional treatments, but supplemental bovine lactoferrin was not beneficial under these experimental conditions.

Endovascular Repair or Surveillance of Patients with Small AAA

OBJECTIVE

To compare the outcome of patients with small abdominal aortic aneurysms (AAA) treated in a prospective trial of endovascular aneurysm repair (EVAR) to patients randomized to the surveillance arm of the UK Small Aneurysm Trial.

METHOD

All patients with small AAA (< or = 5.5 cm diameter) treated with a stent graft (EVARsmall) in the multicenter AneuRx clinical trial from 1997 to 1999 were reviewed with follow up through 2003. A subgroup of patients (EVARmatch) who met the age (60-76 years) and aneurysm size (4.0-5.5 cm diameter) inclusion criteria of the UK Small Aneurysm Trial were compared to the published results of the surveillance patient cohort (UKsurveil) of the UK Small Aneurysm Trial (NEJM 346:1445, 2002). Endpoints of comparison were aneurysm rupture, fatal aneurysm rupture, operative mortality, aneurysm related death and overall mortality. The total patient years of follow-up for EVAR patients was 1369 years and for UK patients was 3048 years. Statistical comparisons of EVARmatch and UKsurveil patients were made for rates per 100 patient years of follow up (/100 years) to adjust for differences in follow-up time.

RESULTS

The EVARsmall group of 478 patients comprised 40% of the total number of patients treated during the course of the AneuRx clinical trial. The EVARmatch group of 312 patients excluded 151 patients for age < 60 or > 76 years and 15 patients for AAA diameter < 4 cm. With the exception of age, there were no significant differences between EVARsmall and EVARmatch in pre-operative factors or post-operative outcomes. In comparison to the UKsurveil group of 527 patients, the EVARmatch group was slightly older (70 +/- 4 vs. 69 +/- 4 years, p = 0.009), had larger aneurysms (5.0 +/- 0.3 vs. 4.6 +/- 0.4 cm, p < 0.001), fewer women (7 vs. 18%, p < 0.001), and had a higher prevalence of diabetes and hypertension and a lower prevalence of smoking at baseline. Ruptures occurred in 1.6% of EVARmatch patients and 5.1% of UKsurveil patients; this difference was not significant when adjusted for the difference in length of follow up. Fatal aneurysm rupture rate, adjusted for follow up time, was four times higher in UKsurveil (0.8/100 patient years) than in EVARmatch (0.2/100 patient years, p < 0.001); this difference remained significant when adjusted for difference in gender mix. Elective operative mortality rate was significantly lower in EVARmatch (1.9%) than in UKsurveil (5.9%, p < 0.01). Aneurysm-related death rate was two times higher in UKsurveil (1.6/100 patient years) than in EVARmatch (0.8/100 patient years, p = 0.03). All-cause mortality rate was significantly higher in UKsurveil (8.3/100 patient years) than in EVARmatch (6.4/100 patient years, p = 0.02).

CONCLUSIONS

It appears that endovascular repair of small abdominal aortic aneurysms (4.0-5.5 cm) significantly reduces the risk of fatal aneurysm rupture and aneurysm-related death and improves overall patient survival compared to an ultrasound surveillance strategy with selective open surgical repair.

Chromosomal localization of three vacuolar-H+ -ATPase 16 kDa subunit (ATP6V0C) genes in the murine genome

Vacuolar-H(+)-ATPase (V-H-ATPase) is a large multimeric protein composed of at least 12 distinct subunits. The 16-kDa hydrophobic proteolipid subunit (ATP6V0C; ATPase, H(+ )transporting, lysosomal 16 kDa, V0 subunit C) plays a central role in H(+) transport across cellular membranes. We have mapped three ATP6V0C genes (Atp6v0c, Atp6v0c-ps1 and Atp6voc-ps2) in the murine genome. Atp6v0c-ps1 and Atp6v0c-ps2 map to Chromosomes 7 and 6, respectively. Atp6v0c maps to Chromosome 17, closely linked to the Tsc2 locus and D17Mit55. This region of Chromosome 17 in mouse is homologous with chromosome 16 in human where the ATP6V0C gene is localized.

Gene expression in the developing mouse retina by EST sequencing and microarray analysis

Retinal development occurs in mice between embryonic day E11.5 and post-natal day P8 as uncommitted neuroblasts assume retinal cell fates. The genetic pathways regulating retinal development are being identified but little is understood about the global networks that link these pathways together or the complexity of the expressed gene set required to form the retina. At E14.5, the retina contains mostly uncommitted neuroblasts and newly differentiated neurons. Here we report a sequence analysis of an E14.5 retinal cDNA library. To date, we have archived 15 268 ESTs and have annotated 9035, which represent 5288 genes. The fraction of singly occurring ESTs as a function of total EST accrual suggests that the total number of expressed genes in the library could approach 27 000. The 9035 ESTs were categorized by their known or putative functions. Representation of the genes involved in eye development was significantly higher in the retinal clone set compared with the NIA mouse 15K cDNA clone set. Screening with a microarray containing 864 cDNA clones using wild-type and brn-3b (-/-) retinal cDNA probes revealed a potential regulatory linkage between the transcription factor Brn-3b and expression of GAP-43, a protein associated with axon growth. The retinal EST database will be a valuable platform for gene expression profiling and a new source for gene discovery.

Vena caval filter placement by intravascular ultrasound

OBJECTIVE

Placement of vena caval filters under fluoroscopic surveillance incurs significant expense and potential risks associated with the transportation of critically ill patients. Intravascular ultrasound (IVUS) allows direct intraluminal visualization of the vena cava and the renal veins. The purpose of this study is to evaluate the accuracy of vena caval filter placement under IVUS in an animal model.

METHODS

Fifteen Simon-Nitinol venal cava filters (C.R. Bard, Inc., Covington, GA) were placed under IVUS guidance into four anesthetized sheep. Twelve were placed transfemorally, and three were placed transjugularly. Accuracy of placement was confirmed with fluoroscopy by measurement between the filter tip and the targeted side branch.

RESULTS

The vena caval filters placed femorally averaged 0.33+/-0.42 cm distance from the target vein side branch. Jugular approach filter placement was less accurate. Although two out of three filters placed from the jugular vein were correctly positioned, the distance from the target vein side branch was much greater averaging 2.5+/-1.04 cm.

CONCLUSION

Femoral placement of vena caval filters under IVUS is extremely accurate. The transjugular route, however, was technically challenging and standard fluoroscopic vena caval filter placement appears to be more appropriate. Our success with the femoral approach merits further clinical investigation in the use of IVUS for critically ill patients that would benefit from bedside vena caval filter placement.

Modelling pencil-beam divergence with the electron pencil-beam redefinition algorithm

The electron pencil-beam redefinition algorithm (PBRA), which is used to calculate electron beam dose distributions, assumes that the virtual source of each pencil beam is identical to that of the broad beam incident on the patient. In the present work, a virtual source specific for each pencil beam is modelled by including the source distance as a pencil-beam parameter to be redefined with depth. To incorporate a variable pencil-beam source distance parameter, the transport equation was reformulated to explicitly model divergence resulting in the algorithm divPBRA. Allowing the virtual source position to vary with individual pencil beams is expected to better model the effects of heterogeneities on local electron fluence divergence (or convergence). Selected experiments from a measured data set developed at The University of Texas M D Anderson Cancer Center were used to evaluate the accuracy of the dose calculated using divPBRA. Results of the calculation showed that the theory accurately predicted the virtual source position in regions of side-scatter equilibrium and predicted reasonable virtual source positions in regions lacking side-scatter equilibrium (i.e. penumbra and in the vicinity and shadow of internal heterogeneities). Results of the evaluation showed the dose accuracy of divPBRA to be marginally better to that of PBRA, except in regions of extremely sharp dose perturbations, where the divPBRA calculations were significantly greater than the measured data. Dose calculations using divPBRA took 45% longer than those using PBRA. Therefore, we concluded that divPBRA offers no significant advantage over PBRA for the purposes of clinical treatment planning. However, the results were promising and divPBRA might prove useful if further modelling were to include large-angle scattering, low-energy delta rays and brehmsstrahlung.

Synergistic inhibition of human lung cancer cell growth by adenovirus-mediated wild-type p53 gene transfer in combination with docetaxel and radiation therapeutics in vitro and in vivo

Chemotherapy given sequentially or concurrently with external beam radiation therapy has emerged as a standard for the treatment of locally advanced lung cancer. Gene therapy by adenovirus-mediated wild-type p53 gene transfer has been shown to inhibit lung cancer growth in vitro, in animal models, and in human clinical trials. However, no information is available on the combined effects of p53 gene transfer, chemotherapy, and radiation therapy on lung cancer growth in vitro and in vivo. Therefore, we developed two-dimensional and three-dimensional isobologram modeling and statistical methods to evaluate the synergistic, additive, or antagonistic efficacy among these therapeutic agents in human non-small cell lung cancer cell lines A549, H460, H322, and H1299, at the ID50 and ID80 levels. The combination of these three therapeutic agents exhibited synergistic inhibitory effects on tumor cell growth in all four cell lines at both the ID50 and the ID80 levels in vitro. In mouse models with H1299 and A549 xenografts, combined treatment synergistically inhibited tumor growth in the absence of any apparent increase in toxicity, when compared with other treatment and control groups. Together, our findings suggest that a combination of gene therapy, chemotherapy, and radiation therapy may be an effective strategy for human cancer treatment.

Early clinical experience with color three-dimensional intravascular ultrasound in peripheral interventions

PURPOSE

To report early clinical experiences with color 3-dimensional intravascular ultrasound (3-D IVUS) in assisting peripheral interventions.

TECHNIQUE

A 3.5-F, 20-MHz IVUS catheter that utilizes ChromaFlo computer software to demonstrate blood flow in color was evaluated in over 100 peripheral interventions. ChromaFlo captures up to 30 conventional IVUS frames every second and generates "real-time" imaging. The software compares sequential axial IVUS images and interprets any differences in the position of echogenic blood particles, which are displayed as colorized flow in axial or 3-D renderings.

CONCLUSIONS

ChromaFlo-enhanced IVUS demonstrates colorized blood flow inside the vessel lumen, which is helpful in distinguishing echolucent disease from luminal blood flow and can also be used to perform peripheral interventions in patients with renal failure or allergy, avoiding the use of contrast media.

Combined omental pedicle grafts and thoracodorsal axial pattern flaps for the reconstruction of chronic, nonhealing axillary wounds in cats

OBJECTIVE

To assess the results of an omental pedicle graft in combination with a thoracodorsal axial pattern flap for the reconstruction of chronic nonhealing axillary wounds in 10 cats caused by forelimb entrapment within a collar.

STUDY DESIGN

A prospective, clinical trial. ANIMALS USED: Ten client-owned domestic shorthair cats.

METHODS

Routine biochemical and hematologic evaluation was performed on each cat, and all were tested for feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV). Microbial culture was performed on samples from the wounds. After surgical debridement, omentalization using a vascular pedicle of greater omentum, and closure of the chronic axillary wounds, using a thoracodorsal axial pattern flap, was performed. All excised tissue was examined histologically.

RESULTS

The sex distribution was 7 males and 3 females, with a mean age of 3.5 years. The cats had undergone a median number of 3 previous repair attempts over a 1.5- to 25-month period before referral (mean, 10.2 months). No hematologic or biochemical abnormalities were noted apart from moderately elevated creatine kinase and aspartate transaminase concentrations in some cats. All cats were negative for FIV and FeLV. Histologic examination of resected tissue revealed hair (foreign body) in 2 cats and an unidentified foreign-body reaction in 3 other cats. Complete healing occurred in all cats (mean follow-up period of 21.7 months), with 2 cats requiring further surgery: 1 for flap dehiscence at 4 days after surgery, and 1 for donor-site dehiscence at 4 days after surgery. One other cat developed a large seroma in the axilla that resolved by 10 days following surgery.

CONCLUSION

The use of an omental pedicle graft in combination with a thoracodorsal axial pattern flap is the first consistently successful 1-step technique for the management of chronic nonhealing axillary wounds in cats.

Healing response of normal canine aorta and iliac artery to a nitinol stent encapsulated in carbon-lined ePTFE

PURPOSE

To evaluate the healing response of normal canine arteries to a self-expanding nitinol stent encapsulated in carbon-lined expanded polytetrafluoroethylene (ePTFE).

METHODS

Twenty-eight dogs were divided into aortic (n = 18) or iliac (n = 10) groups. In the latter, 2 animals were assigned to implantation intervals of 7, 30, and 90 days, respectively; 4 were designated for 180-day implantation. Half of the animals in each subgroup received a second overlapping stent-graft in one iliac artery. In the aortic cohort, 6 animals were assigned to the 180-day implantation group (2 with dual devices) and 3 to each of the others (1 dual implantation in each group). The devices were evaluated with angiography and intravascular ultrasound at implantation and explantation. After harvesting and gross examination, the specimens were examined microscopically and with scanning electron microscopy.

RESULTS

The 49 implanted devices (24 aortic and 25 common iliac) were all widely patent at explantation, save for 2 iliac stents that had moderate (<40%) stenosis. No neointima was present at the 7-day interval. All stents were covered by thin neointima (<150 microm) at 30 days. At 180 days, an endothelial lining was present in the proximal and distal segments of all stents; in 4 of the 6 aortic stents, this endothelial lining was complete, whereas none of the iliac devices had endothelium in the midsegment at 180 days. At 1 year, 2 of the aortic specimens had an incomplete endothelial lining, whereas the lining was complete in the third. There was no evidence of stent-graft migration or inflammation associated with any device.

CONCLUSIONS

The carbon-lined ePTFE-encapsulated stent is a novel approach to arterial stenting. The progressive endothelialization and lack of inflammatory reaction may provide improved long-term patency. Further study of this stent-graft design is warranted.

Failed AAA endograft exclusion due to type II endoleak: explant analysis

PURPOSE

To report the patient history and analysis of an explanted modular bifurcated endograft that was implanted to exclude an abdominal aortic aneurysm (AAA).

CASE REPORT

An 80-year-old man with a 6-cm AAA underwent uneventful endovascular implantation of a bifurcated AneuRx stent-graft. His postprocedural clinical course was uneventful, although persistent contrast enhancement of the aneurysm remained via the inferior mesenteric artery (IMA). By 6 months, an endoleak connecting to the lumbar and mesenteric arteries became apparent. Over the ensuing 12 months, the endoleak and aneurysm enlarged; branch artery embolization was attempted in 4 percutaneous procedures. Despite successful IMA occlusion, the aneurysm continued to increase in diameter and volume, necessitating conversion to a conventional bypass at 20 months. Analysis of the explanted specimen revealed an intact endograft with fibrous incorporation of the stent framework at the proximal and distal fixation sites only; no incorporation of the endograft was noted within the aneurysm. The feeding channel for the endoleak was not identified.

CONCLUSIONS

Serial imaging is a vital component of endograft surveillance, and persistent type II endoleaks that cannot be completely embolized endanger the longevity of the aneurysm exclusion. Explant analysis can play an important role in understanding the mechanisms of endograft failure.

Abdominal pain and hemoperitoneum: sole presenting symptoms for "leaking AAA" after endovascular repair

PURPOSE

To describe an unusual presentation of impending aortic endograft rupture and successful endovascular rescue.

CASE REPORT

A 77-year-old man with an enlarging aortic aneurysm was treated with a Talent bifurcated endoprosthesis; a moderate endoleak that appeared to be related to either proximal or distal fixation sites was noted in the body of the aneurysm. The patient was observed for 1 month, and repeat imaging demonstrated persistent endoleak without major increase in the aneurysm diameter. Another examination was scheduled for 3 months hence, but, 2 months later, the patient presented with abdominal pain and a hemoperitoneum. A proximal extension cuff resolved the leak and led to resolution of the hemoperitoneum.

CONCLUSIONS

A leaking aneurysm can be repaired using endovascular techniques in patients with an existing endograft. The need for frequent imaging surveillance of patients with endoleak is underscored.

Endovascular exclusion of descending thoracic aortic aneurysms and chronic dissections: Initial clinical results with the AneuRx device

OBJECTIVE

The objective of this study was to analyze a single-center experience in which descending thoracic aortic aneurysms (TAAs) were treated with a new self-expanding endovascular prosthesis (Medtronic AVE).

METHODS

Twenty-six patients (13 men, 13 women) with American Society of Anesthesiology grades II to IV and ages ranging from 53 to 92 years (average, 74 years) consented as part of a Phase I Food and Drug Administration-approved trial. Treated lesions included TAAs that were 5 to 10 cm in diameter, 12 diffuse dilations or fusiform aneurysms, and four saccular aneurysms. There were also nine chronic dissections (2 aneurysmal dilations and 7 symptomatic acute recurrent dissections). Three patients (2 with diffuse/fusiform and 1 with dissection) presented with hemothorax, contrast extravasation, or both.

RESULTS

Twenty-five of the 26 patients who consented (96% technical success) were treated successfully with no surgical conversions. Eighteen patients have been followed up from 1 to 22 months (average, 9 months). One patient is lost to follow-up, and six patients have died (24%). One procedure-related death (4%) occurred within the 30-day postoperative period and was caused by diffuse embolization. There were no device-related deaths. Five additional patients (20%) have died during the study of comorbid conditions. Complications included one massive myocardial infarction 24 hours after the procedure requiring balloon counterpulsation and long-term dialysis, one cardiac tamponade resulting from central line placement before the procedure, one progression of aneurysm dilation proximal to the device at 1 year, and one bilateral lower extremity paralysis occurring 12 hours after successful deployment. Seven patients (5 women) had femoral artery reconstructions or iliac artery grafts to repair injuries during deployment catheter passage. Other significant parameters included average procedure time (2 hours 40 minutes; range, 1 hour 30 minutes to 5 hours 30 minutes), 450 cc average blood loss (n = 25; 100-3000 cc) being replaced by means of autotransfusion with only two patients receiving banked blood products, and an average 2 days to resumption of normal diet, 1 day in the intensive care unit, and 5 days' hospitalization postprocedure in uncomplicated cases (n = 22). One patient had an endoleak immediately after the procedure that sealed without treatment. Follow-up of all patients ranging from 1 to 22 months (average, 9 months; n = 18) demonstrates continued exclusion of the aneurysm with no endoleaks and either stable or decreasing aneurysm volume, except in one patient with volume increase and no obvious etiology who continues to be investigated.

CONCLUSIONS

The study suggests that endovascular prosthesis exclusion of TAAs with an AneuRx self-expanding tubular device may be effective in many patients who are at significant risk for open surgical repair and substantiates further clinical investigation to confirm these findings.

Clinical and design update on the development and testing of a one-piece, bifurcated, polytetra-fluoroethylene endovascular graft for abdominal aortic aneurysm exclusion: the Endologix device

Continued success and expanding use of endovascular prostheses to manage aortic aneurysms has encouraged development of novel prototypes that offer advantages for low-profile delivery of durable devices. The Endologix device, currently being acquired by CR Bard, Incorporated, is a new, one-piece self-expanding polytetrafluoroethylene prosthesis that offers an alternative to current modular and fabric devices. Although only preliminary U.S. and expanding European experiences are available, the unique features of this prosthesis appear to offer an appealing alternative.

Synergistic interaction between an anti-p185HER-2 pseudomonas exotoxin fusion protein [scFv(FRP5)-ETA] and ionizing radiation for inhibiting growth of ovarian cancer cells that overexpress HER-2

OBJECTIVES

The HER-2 proto-oncogene is overexpressed in 15-30% of ovarian cancers, providing a target for therapy in a fraction of patients. We previously described the ability of a recombinant single-chain anti-p185HER-2-Pseudomonas exotoxin A fusion protein, scFv(FRP5)-ETA, to inhibit growth of cancer cells in culture and tumor xenografts in vivo. We have also described synergistic interaction between an anti-p185HER-2-ricin A chain immunotoxin and ionizing radiation for inhibiting growth of ovarian and breast cancer cells that overexpress HER-2. Our objective in this report was to evaluate the in vitro and in vivo effects of scFv(FRP5)-ETA against SKOv3 ovarian cancer cells that have been transfected to express >10(6) p185HER-2 receptors per cell (clone-9002-18).

METHODS

Inhibition of clonogenic growth was measured in vitro by limiting dilution analysis. Inhibition of tumor growth was measured in vivo using heterografts established with the same ovarian cancer cell lines.

RESULTS

Clone-9002-18 cells were substantially more sensitive than parental SKOv3 cells to the cytotoxic effects of scFv(FRP5)-ETA. Exotoxin fusion protein induced apoptosis in clone-9002-18 cells, but did not affect parental SKOv3 cells. Treatment of clone-9002-18 cells with 200- to 2000-cGy external beam irradiation in combination with scFv(FRP5)-ETA produced synergistic elimination of clonogenic tumor cells in culture. In vivo, subcutaneous or intraperitoneal growth of tumor xenografts in nu/nu mice was significantly inhibited (P = 0.004) by treatment for 10 days with scFv(FRP5)-ETA or with 131I-labeled-520C9 anti-p185HER-2 radionuclide conjugate, but additive effects were not observed with combined treatment.

CONCLUSION

ScFv(FRP5)-ETA deserves further evaluation for intraperitoneal therapy of ovarian cancers that overexpress p185HER-2.

Computed tomography assessment of abdominal aortic aneurysm morphology after endograft exclusion

OBJECTIVES

Assessment of the long-term function of endografts to exclude abdominal aortic aneurysm (AAA) includes determination of aneurysm dimensions and morphologic changes that occur after implantation. This study reports the dimensional analysis of patients treated with AneuRx bifurcated endoprostheses with postintervention, 1-year (n = 51), 2-year (n = 28), and 3-year (n = 10) postimplantation contrast computed tomography data.

METHODS

Maximal diameter (D) and cross-sectional area (CSA) of the AAA were measured from axial computed tomography images. Total volume, AAA thrombus volume (AAA volume minus the volume of the device and luminal blood flow), diameter of the aorta at the level of the renal arteries and within the device, distance from the renal arteries to the device, length of the device limbs, and the angle of the proximal neck were also determined at the same follow-up intervals after deployment with computed tomography angiograms reconstructed in an interactive environment.

RESULTS

Fifty-one of 98 consecutively treated patients with the AneuRx bifurcated prosthesis (29 "stiff" and 22 "flexible" body devices) had complete data from the postprocedure and follow-up computed tomography studies available for analysis. Max D, CSA, total volume of the AAA, and AAA thrombus volume decreased sequentially from year to year compared with the postimplantation values. D and CSA decreased or were unchanged in all except four patients, two who had unrestricted enlargement of the aneurysm with eventual rupture and one who had surgical conversion for continued expansion despite four diagnostic angiograms and attempted embolizations. Total volume of the AAA increased in 11 of 51 patients at 1 year, eight of whom had endoleaks at some interval during the follow-up. Thrombus volume increased more than 5% in four of these patients, including the two with eventual rupture and the one conversion. Patients with endoleaks who had spontaneous thrombosis or were successfully treated either remained at the same volume or had decreased volume on subsequent examinations. D at the renal arteries increased an average of 0.9 mm during the first year, with a concomitant increase of 2.8 mm within the proximal end of the device related to the self-expanding nature of the Nitinol suprastructure. Subsequent enlargement of the proximal neck continued at a slow rate in some cases but never exceeded the diameter of the endoluminal device. The distance from the renal arteries to the device increased by an average of 3 mm over the first year, with the greatest increases occurring in patients with a "stiff" body device and those with rapid regression (>10% total volume) in 1 year. As regression of the AAA occurred, the angle of the proximal neck varied from -5 degrees to +25 degrees from the original alignment. Limb length varied from -8 mm to +10 mm, with no consistent pattern for the change, that is, ipsilateral or contralateral limb.

CONCLUSION

Significant variation in the quantitation of aneurysm size occurs depending on the technique of computed tomography assessment used. In most patients diameter assessment is adequate, although volumetric analysis appears to be very helpful in certain patients who do not show aneurysm regression, or in whom the diameter increases or where endoleaks persist. Three-dimensional reconstruction and volumetric analysis are also useful to assess the mechanism by which the endovascular device accommodates to morphology changes and to determine criteria for reintervention.

The AneuRx stent graft: four-year results and worldwide experience 2000

OBJECTIVE

The objective was to review the current results of endovascular abdominal aortic aneurysm repair with the AneuRx stent graft and to determine the effectiveness of the device in achieving the primary objective of preventing aneurysm rupture.

METHODS

The outcome of all patients treated during the past 4 years in the U.S. AneuRx clinical trial was determined, and the worldwide clinical experience was reviewed.

RESULTS

A total of 1192 patients were treated with the AneuRx stent graft during all phases of the U.S. Clinical Trial from June 1996 to November 1999, with follow-up extending to June 2000. Ten (0.8%) patients have had aneurysm rupture, with most ruptures (n = 6) occurring in 174 (3.4%) patients treated with an early stiff bifurcation stent graft design used in phase I and in the initial stages of phase II. Since the current, flexible, segmented bifurcation stent graft design was introduced, four (0.4%) ruptures have occurred among 1018 patients treated. Of these, one was during implantation, two were placed too far below the renal arteries, and one patient refused treatment of a type I endoleak. Kaplan-Meier analysis of all 1192 patients treated with the AneuRx stent graft including both stent graft designs revealed the patient survival rate to be 93% at 1 year, 88% at 2 years, and 86% at 3 years, freedom from conversion to open repair to be 98% at 1 year, 97% at 2 years, and 93% at 3 years, and freedom from secondary procedure to be 94% at 1 year, 92% at 2 years, and 88% at 3 years. Freedom from aneurysm rupture with the commercially available segmented bifurcation stent graft was 99.7% at 1 year, 99.5% at 2 years, and 99.5% at 3 years. The presence or absence of endoleak on contrast computed tomography scanning after stent graft placement was not found to be a significant predictor of long-term outcome measures. Worldwide experience with the AneuRx device now approaches 10,000 patients.

CONCLUSIONS

Endovascular management of abdominal aortic aneurysms with the AneuRx stent graft has markedly reduced the risk of aneurysm rupture while eliminating the need for open aneurysm surgery in 98% of patients at 1 year and 93% of patients at 3 years. The device was effective in preventing aneurysm rupture in 99.5% of patients over a 3-year period. The overall patient survival rate was 93% at 1 year and 86% at 3 years.

A novel 16-kilodalton cellular protein physically interacts with and antagonizes the functional activity of c-myc promoter-binding protein 1

We initially identified c-myc promoter-binding protein 1 (MBP-1) from a human cervical carcinoma cell expression library which negatively regulates c-myc promoter activity. A recent study demonstrated that MBP-1 acts as a general transcriptional repressor (A. K. Ghosh, R. Steele, and R. B. Ray, Mol. Cell. Biol. 19:2880-2886, 1999). In order to identify the cellular protein(s) interacting with MBP-1 for transcriptional regulation, a HeLa cell cDNA expression library was screened using a yeast two-hybrid system. An MBP-1-interacting cDNA encoding a polypeptide of 140 amino acid residues with an approximate molecular mass of 16 kDa was identified and named MBP-1 interacting protein-2A (MIP-2A). MIP-2A has a sequence similarity with an unknown mRNA and SEDL. Mutations in the SEDL gene, located at human chromosome Xp22, has recently been implicated with an X-linked genetic disease, although the function of SEDL gene product was not determined (A. K. Gedeon et al., Nat. Genet. 22:400-404, 1999). However, our results suggested the localization of MIP-2A at human chromosome 19. The specificity of interaction between MBP-1 and MIP-2A was verified by an in vitro glutathione S-transferase pulldown experiment, a mammalian two-hybrid analysis, and in vivo coimmunoprecipitation assays. Further analysis revealed that the amino-terminal domain of MBP-1 (amino acids 1 to 95) interacts with MIP-2A. Immunofluorescent staining suggested colocalization of MIP-2A and MBP-1 primarily in the perinuclear membrane of cells. Functional analysis demonstrated that MIP-2A relieves MBP-1 mediated transcriptional repression on c-myc promoter. Additionally, MIP-2A antagonizes cell growth regulatory role of MBP-1. Taken together, these results suggest the functional interaction of MIP-2A and MBP-1 in cell growth regulation.

Management of inflammatory polyps in 37 cats

The case records of 37 cats treated for nasopharyngeal or aural inflammatory polyps were reviewed. Thirty of them were managed conservatively with the polyp being removed by traction alone. Long-term follow-up information was available for 22 cats, of which 13 (59 per cent) had no recurrence of clinical signs. The remaining nine cats required recurrent polyps to be removed surgically. Cats with only nasopharyngeal polyps were nearly four times more likely to be cured by traction alone than cats with aural polyps, and none of the cats that was treated with prednisolone after traction suffered a recurrence. Cats with more severe aural signs were more likely to require surgery.

Ischemic bandage injuries: a case series and review of the literature

OBJECTIVE

To determine the prognosis and distribution of ischemic injuries caused by inappropriate bandaging of the lower limb in dogs and cats.

STUDY DESIGN

Retrospective clinical study.

ANIMAL POPULATION

Eleven client-owned animals, including 9 dogs and 2 cats with a history of injuries consistent with incorrect application of a bandage.

METHODS

Medical records for dogs and cats referred to the Queen's Veterinary School Hospital with limb wounds between 1995 and 1999 were reviewed for clinical history and referring veterinary surgeons' reports, indicating that the injury was directly related to the application of a bandage to the limb.

RESULTS

The indications for bandage application included 2 postoperative cruciate ligament ruptures, 2 lacerations, 3 internal fixations, an onychectomy, a shoulder dislocation, a dog bite, and a tendon strain. None of the patients had other body systems involved or underlying or concurrent diseases. Five different types of bandage were described (support, Robert Jones, pressure, splint, and Velpeau), and no particular age or breed was overrepresented. Of the 11 animals, 5 required full-thickness skin grafts, 3 had to have digits amputated, and 2 required limb amputations. Nine animals survived, but only 4 became fully functional on the affected limb.

CONCLUSIONS

Bandage-related injuries are potentially serious sequelae to a routine procedure. A guarded prognosis should be given when there is loss of deeper structures.

CLINICAL RELEVANCE

A review of bandaging principles is presented. Method of application, choice of materials, and close monitoring of the bandage are important factors in preventing iatrogenic injury.

Traumatic subcutaneous translocation of the spleen in an Old English sheepdog

A 14-month-old entire male Old English sheepdog was presented with a slowly enlarging subcutaneous soft tissue swelling caudal to the last rib. Radiographic and ultrasonographic Investigations demonstrated a soft tissue mass closely adherent to the body wall, with a coarse hypoechoic pattern. Surgical exploration revealed a mass with the gross appearance of splenic tissue. The mass was adhered to a healed paracostal abdominal tear. Histological examination confirmed the resected tissue to be normal spleen.

Squamous cell carcinoma of the nasal planum in 17 dogs

Squamous cell carcinoma of the nasal planum was diagnosed in 17 dogs over a period of 11 years. Ulceration, bleeding and sneezing were the most common clinical signs. One dog had cytological evidence of metastasis to the local lymph node. The dogs were treated by surgical resection, fractionated megavoltage irradiation, or a combination of the two. Surgical resection gave the most favourable results; four of six dogs were cured but a recurrence of the tumour was predicted in the other two on the basis of incomplete or marginal resection. Radiotherapy alone was not as effective; one of four dogs was cured, and the tumour recurred in the others within 24 weeks (median eight weeks). Combined surgical resection and radiotherapy did not produce a cure in any of the seven remaining dogs, and the tumour recurred within 12 weeks (median nine weeks). Three dogs had cytological evidence of lymph node metastasis when the tumour recurred. The dogs' prognosis was adversely affected by the interval between their initial examination and treatment, but there was no apparent association between the histological grade of the tumour and the clinical outcome.

The gene encoding TBC1D1 with homology to the tre-2/USP6 oncogene, BUB2, and cdc16 maps to mouse chromosome 5 and human chromosome 4

TBC1D1 is the founding member of a family of related proteins with homology to tre-2/UPS6, BUB2, and cdc16 and containing the tbc box motif of 180-220 amino acids. This protein family is thought to have a role in differentiation and in regulating cell growth. We set out to map the TBC1D1 gene in mouse and human. Segregation analysis of a TBC1D1 RFLP in two independent mouse RI (recombinant inbred) lines reveals that mouse Tbc1d1 is closely linked to Pgm1 on chromosome 5. The human TBC1D1 gene was assigned to human chromosome 4p15.1-->4q21 using Southern blot analyses of genomic DNAs from rodent-human somatic cell lines. A human-specific genomic fragment was observed in the somatic cell lines containing human chromosome 4 or the 4p15.1-->4q21 region of the chromosome. TBC1D1 maps to the region containing the ortholog of mouse Pgm1 adding another locus to this long region of conserved synteny between mouse and man.

Genomic organization, chromosomal localization and regulation of expression of the neuronal nuclear matrix protein NRP/B in human brain tumors

The nuclear matrix and its role in cell physiology are largely unknown, and the discovery of any matrix constituent whose expression is tissue- and/or cell-specific offers a new avenue of exploration. Studies of the novel neuronal nuclear matrix protein, NRP/B, reveal that it is an early and highly specific marker of neuronal induction and development in vertebrates, since its expression is restricted mainly to the developing and mature nervous system. These studies also show that NRP/B is involved in neuronal differentiation. To further examine the structure-function of NRP/B, we have cloned and characterized the murine Nrp/b gene. The murine gene consists of four exons interrupted by three introns that span 7.6kb of DNA. The complete open reading frame is localized in exon 3, suggesting that NRP/B is highly conserved during evolution. Chromosomal analysis shows that NRP/B is localized to chromosome 13 in mouse and chromosome 5q12-13 in human. Since our previous studies demonstrated that NRP/B is expressed in primary hippocampal neurons but not in primary astrocytes, we have characterized NRP/B mRNA and protein expression in various brain cell lines and in human brain tumors. Abundant expression of NRP/B mRNA and protein was observed in human neuroblastoma cell lines (IMR32, SKN-MC, SKN-SH), in glioblastoma cell lines (A172, T98G, U87-MG, U118-MG, U138-MG, and U373-MG), in neuroglioma (H4) and astrocytoma cell lines (CCF-STTG1 and SW1088). Confocal analysis of NRP/B in U87-MG glioblastoma cells indicated nuclear localization of NRP/B. NRP/B expression was also observed in human primary brain tumors including glioblastoma multiformae and astrocytomas (total of five cases). These results suggest that NRP/B expression is upregulated in human brain tumors including glioblastomas and astrocytomas, while under normal conditions NRP/B expression is restricted to neurons. This study implicates a role for NRP/B in brain tumor development.

Simultaneous estimation of T(G2+M), T(S), and T(pot) using single sample dynamic tumor data from bivariate DNA-thymidine analogue cytometry

BACKGROUND

Estimating the duration of S phase (T(S) ) and the potential doubling time (T(pot) ) from a single time measurement of the movement of cells using bivariate cytometry is common. However, these estimates require an assumption of the duration of G2 + M (T(G2+M) ). Inspection of the measured dynamic quantities, relative movement [RM(t)], fractions of labeled divided and undivided cells (f(lu)(t) and f(ld)(t)) suggests that T(G2+M), T(S), and T(pot) can be determined simultaneously.

METHODS

An equation connecting the growth of the cell population, time, and the dynamic quantities was determined. The equation cannot be solved analytically, but accurate approximations can be used to find T(pot). From this result, the value of T(G2+M) can be determined from f(ld)(t), and T(S) can be determined from RM(t).

RESULTS

Kinetic parameters obtained from single time estimates using the new method compared to those obtained from the analysis of multiple time-point measurements of MCa-K and MCa-4 murine tumors are shown to be in close agreement. Moreover, estimates of T(G2+M) in MCa-4 tumors, treated with paclitaxel, provide extra information on the changes in T(G2+M). When applied to the rat R3327-G prostate tumor model following androgen ablation, a correlation analysis of the T(pot) values obtained by the new and previous single time-point methods demonstrates that the rank order from shortest to longest T(pot) values are largely preserved.

CONCLUSIONS

The new procedure makes direct estimation of T(G2+M) possible from single time-dynamic measurements. The results from previous studies on T(S) and T(pot) are largely unchanged, but extra information is now available.

Abdominal aortic aneurysm rupture following endoluminal graft deployment: report of a predictable event

PURPOSE

To describe the predictability of an abdominal aortic aneurysm (AAA) rupture secondary to a type II endoleak following stent-graft exclusion.

METHODS AND RESULTS

An 81-year-old man with an enlarging AAA underwent endovascular repair using an AneuRx aortic stent-graft, but a type II endoleak fed by an accessory renal artery was detected at postprocedural computed tomography (CT). Surveillance CT scans at 6 and 16 months showed an increase in the aneurysm diameter and endoleak volume, but the patient refused advised treatment to close the leak. He suffered a fatal aneurysm rupture 24 months after endografting. Retrospective analysis of CT data documented progressive aneurysm enlargement that correctly predicted the rupture.

CONCLUSIONS

Type II endoleaks can lead to aneurysm rupture. Three-dimensional (3D) spiral CT angiography offers an opportunity to track endoleak volume and the effect of exposure to systemic pressure on the aneurysm sac.

Endoleak as a predictor of outcome after endovascular aneurysm repair: AneuRx multicenter clinical trial

OBJECTIVE

The purpose of this study was to determine whether evidence of blood flow in the aneurysm sac (endoleak) is a meaningful predictor of clinical outcome after successful endovascular aneurysm repair.

METHODS

We reviewed all patients in Phase II of the AneuRx Multicenter Clinical Trial with successful stent graft implantation and predischarge contrast computed tomographic (CT) imaging. The clinical outcome of patients with evidence of endoleak was compared with the outcome of patients without evidence of endoleak. The CT endoleak status before hospital discharge at 6, 12, and 24 months was determined by each clinical center as well as by an independent core laboratory. Endoleak status at 1 month was assessed with duplex scanning examination or CT at each center without confirmation by the core laboratory.

RESULTS

Centers reported endoleaks in 152 (38%) of 398 patients on predischarge CT, whereas the core laboratory reported endoleaks in 50% of these patients (P <.001). The center-reported endoleak rate decreased to 13% at 1 month. Follow-up extended to 2 years (mean, 10 +/- 4 months). One patient had aneurysm rupture and underwent successful open repair at 14 months. This patient had a Type I endoleak at discharge but no endoleak at 1 month or at subsequent follow-up times. There were no differences between patients with and patients without endoleak at discharge in the following outcome measures: patient survival, aneurysm rupture, surgical conversion, the need for an additional procedure for endoleak or graft patency, aneurysm enlargement more than 5 mm, the appearance of a new endoleak, or stent graft migration. Despite a higher endoleak rate identified by the core laboratory, neither the endoleak rate reported by the core laboratory nor the endoleak rate reported by the center at discharge was significantly related to subsequent outcome measures. Patients with endoleak at 1 month were more likely to undergo an additional procedure for endoleak than patients without endoleaks. Patients with Type I endoleaks at discharge and patients with endoleak at 1 month were more likely to experience aneurysm enlargement at 1 year. However, there was no difference in patient survival, aneurysm rupture rate, or primary or secondary success rate between patients with or without endoleak. Actuarial survival of all patients undergoing endovascular aneurysm repair was 96% at 1 year and was independent of endoleak status. Primary outcome success was 92% at 12 months and 88% at 18 months. Secondary outcome success was 96% at 12 months and 94% at 18 months.

CONCLUSIONS

The presence or absence of endoleak on CT scan before hospital discharge does not appear to predict patient survival or aneurysm rupture rate after endovascular aneurysm repair using the AneuRx stent graft. Although the identification of blood flow in the aneurysm sac after endovascular repair is a meaningful finding and may at times indicate inadequate stent graft fixation, the usefulness of endoleak as a primary indicator of procedural success or failure is unclear. Therefore, all patients who have undergone endovascular aneurysm repair should be carefully followed up regardless of endoleak status.

Three novel paralogs of the rodent prolactin gene family

The prolactin (PRL) family consists of a collection of genes expressed in the uterus, placenta and anterior pituitary. These cytokines/hormones participate in the control of maternal-fetal adaptations to pregnancy. In this report, we establish the presence of three new members of the PRL family. Novel expressed sequence tags (ESTs) with homology to PRL were isolated from embryonic and placental cDNA libraries. The cDNAs were sequenced and compared with those of other members of the PRL family. The three new cDNAs were assigned to the PRL family on the basis of sequence similarities and were referred to as PRL-like protein-J (PLP-J), PRL-like protein-K (PLP-K) and PRL-like protein-M (PLP-M). Both rat and mouse PLP-J cDNAs were identified. Rat PLP-J cDNA encodes for a predicted 211 amino acid protein containing a 29 amino acid signal peptide and two putative N-linked glycosylation sites, whereas the mouse PLP-J cDNA encodes for a 212 amino acid protein containing a 29 amino acid signal peptide with a single N-linked glycosylation site. Rat and mouse PLP-J proteins share approximately 79% and 70% nucleotide and amino acid sequence identity, respectively. A full-length rat PLP-K cDNA and a partial tentative mouse PLP-K cDNA were identified. The rat PLP-K cDNA encodes for a predicted 228 amino acid protein containing a 31 amino acid signal peptide and one putative N-linked glycosylation site; the mouse PLP-M cDNA encodes for a predicted 228 amino acid protein containing a 28 amino acid signal peptide and one putative N-linked glycosylation site. Genes for PLP-J, PLP-K and PLP-M are situated at the Prl family locus on mouse chromosome 13. PLP-J was exclusively expressed in decidual tissue from both the mouse and rat. PLP-K was expressed in trophoblast cells of the chorioallantoic placenta and showed an apparent species difference. In the mouse, virtually all trophoblast lineages expressed PLP-K, whereas in the rat, PLP-K expression was restricted to the labyrinthine trophoblast cells. Mouse PLP-M expression was restricted to the junctional zone of the chorioallantoic placenta. In summary, we have identified three new members of the rodent PRL gene family that are expressed in uterine and placental structures. Future experimentation is needed to determine the specific roles of each of these ligands in the biology of pregnancy.

GFP-centrin as a marker for centriole dynamics in living cells

A long-standing puzzle in cell biology is the question of how cells generate one and only one new centrosome in each cell cycle and what is the role of the centriole pair in this process. In this study, the introduction of GFP-centrin into cultured cells allows direct visualization of centriole behavior in living cells and in real time. Using this method, centriole dynamics can be observed throughout the cell cycle and following a variety of experimental treatments. Our studies demonstrate that the biogenesis of new centrioles from individual members of a preexisting centriole pair is asynchronous: the older centriole initiates assembly of a new daughter centriole before the younger centriole initiates assembly of its daughter.

Aneurysm rupture after endovascular repair using the AneuRx stent graft

OBJECTIVE

The purpose of this study was to determine the cause and frequency of aneurysm rupture after endovascular aneurysm repair.

METHODS

We reviewed each patient who sustained aneurysm rupture among all patients enrolled for endovascular aortic aneurysm repair in phases I, II, and III of the US AneuRx Multicenter Clinical Trial from June 1996 through October 1999.

RESULTS

A total of 1067 patients were enrolled for endovascular aneurysm repair. The AneuRx stent graft was successfully implanted in 1046 patients (98%). Endovascular repair was unsuccessful in 21 patients (2%); 13 patients (1%) were converted to open aneurysm repair. Among these, two patients (0.2%) sustained aneurysm rupture due to procedure-related instrumentation and underwent open surgical conversion. Aneurysm rupture has occurred in seven patients (0.7%) 3 weeks to 24 months (mean, 16 months) after successful endovascular repair. Four patients survived open surgical repair, and three patients died within 30 days. Overall rupture-related mortality was 0.5% and included late deaths after rupture. Before rupture, two patients had endoleak and aneurysm enlargement, and five patients had no endoleak and no aneurysm enlargement. After aneurysm rupture all seven patients had evidence suggesting that there was poor fixation of the stent graft at the proximal distal, or iliac junction fixation sites. The two patients with endoleak declined recommended open surgical or endovascular repair, which could have prevented aneurysm rupture. In retrospect, the five patients without endoleak could potentially have avoided rupture with better patient selection, better stent graft positioning, or reinforcement of fixation points with stent graft extenders. The probability of no aneurysm rupture for all patients undergoing endovascular repair is 0.996 +/- 0.002 at 1 year and 0.974 +/- 0.011 at 2 years by life table analysis with the longest follow-up of 41 months.

CONCLUSION

The early risk of aneurysm rupture after endovascular aneurysm repair is low. However, the possibility of rupture persists even in patients with no endoleak after the procedure. Therefore, all patients treated with endovascular aneurysm repair should continue to be monitored after the procedure. Patients with evidence suggesting insecure stent graft fixation should undergo further endovascular treatment or open surgical repair.

The design and analysis of a homeotic response element

We have shown that the 26 bp bx1 element from the regulatory region of Distal-less is capable of imposing control by the homeotic genes Ultrabithorax and abdominal-A on a general epidermal activator in Drosophila. This provides us with an assay to analyze the sequence requirements for specific repression by these Hox genes. Both the core Hox binding site, 5'-TAAT, and the adjacent EXD 5'-TGAT core site are required for repression by Ultrabithorax and abdominal-A. The Distal-less bx1 site thus fits with the model of Hox protein binding specificity based on the consensus PBX/HOX-family site TGATNNAT[g/t][g/a], where the key elements of binding specificity are proposed to lie in the two base pairs following the TGAT. A single base pair deletion in the bx1 sequence generates a site, bx1:A(-)mut, that on the consensus PBX/HOX model would be expected to be regulated by the Deformed Hox gene. We observed, however, that the bx1:A(-)mut site was regulated predominantly by Sex combs reduced, Ultrabithorax and abdominal-A. The analysis of this site indicates that the specificity of action of Hox proteins may depend not only on selective DNA binding but also on specific post-binding interactions.

Prostatic surgery in the dog

Prostatic diseases are commonly encountered in the dog and a significant proportion of these will require some form of surgical intervention for their successful resolution. The previous perception of the prostate as an obscure pelvic organ coupled with a range of heretofore complex and unsatisfactory surgical techniques have deterred many surgeons from attempting surgical intervention. The recent introduction of omentalization techniques for the management of prostatic infections and secretory abnormalities, which require only modest surgical expertise, has now provided simple solutions for all benign parenchymal diseases. However, neoplastic disease remains a difficult disease both to diagnose and manage.

Structure, expression, and chromosomal localization of the mouse Atox1 gene

Copper trafficking in eukaryotes involves small proteins termed metallochaperones, which mediate copper delivery to specific intracellular sites. Previous studies in yeast and human cell lines have suggested that Atox1 plays a critical role in copper delivery to the secretory pathway. In the present study, a mouse Atox1 (mAtox1) cDNA was cloned and shown to encode an open reading frame with 85% amino acid identity to human Atox1. RNA blot analysis revealed that mAtox1 was expressed as a single transcript in multiple tissues, and immunoblotting indicated that the relative abundance of mAtox1 mRNA directly correlated with mAtox1 protein. Analysis of the mAtox1 gene locus revealed a genomic structure with four exons encompassing a total of 14.5 kb. RFLP and haplotype analyses indicated that the mAtox1 locus was tightly linked to the Trhr and D15Bir7 loci on mouse chromosome 15. Taken together, these data reveal marked evolutionary conservation of Atox1 structure and provide a genomic organization and localization that will aid in the genetic deciphering of the molecular role of this protein in copper homeostasis.

The impact of intravascular ultrasound (IVUS) on endovascular interventions

Intravascular ultrasound (IVUS) has undergone rapid evolution with the recent expansion of endovascular techniques and devices. This device can aid the surgeon, cardiologist, and interventional radiologist by increasing the accuracy of imaging and by adding important information to peripheral vascular and coronary interventions. Modern intravascular ultrasound provides a detailed view of the lumen, wall, and surrounding structures of blood vessels. Compared with other modalities, the diagnostic advantages of IVUS for examining arterial wall architecture and lesion morphology are evident. IVUS can determine lesion shape, length, and configuration, as well as identifying and examining the origins of branches and tributaries. Using this information, IVUS can guide the choice of appropriate angioplasty techniques, aid in the placement of endovascular devices, and assess and follow the efficacy of such interventions. IVUS helps reduce the use of radiation and contrast agents. Even though intravascular ultrasound requires additional equipment, personnel, and interpretative skills, it can be invaluable as a sensitive real-time imaging tool for complex endovascular interventions, therapeutic challenges, and diagnostic dilemmas.

Microtubule nucleating capacity of centrosomes in tissue sections

We used a novel adaptation of methods for microtubule polymerization in vitro to assess the MTOC activity of centrosomes in frozen-sectioned tissues. Remarkably, centrosomes of tissue sections retain the ability to nucleate microtubules even after several years of storage as frozen tissue blocks. Adaptations of these methods allow accurate counts of microtubules from individual cells and the quantitative estimation the MTOC activity of the intact tissue. These methods can be utilized to characterize MTOC activity in normal and diseased tissues and in particular tissues at different stages of development. (J Histochem Cytochem 47:1265-1273, 1999)

Duchenne/Becker muscular dystrophy: correlation of phenotype by electroretinography with sites of dystrophin mutations

The dark-adapted electroretinogram (ERG) of patients with Duchenne and Becker muscular dystrophy (DMD/BMD) shows a marked reduction in b-wave amplitude. Genotype-phenotype studies of mouse models for DMD show position-specific effects of the mutations upon the phenotype: mice with 5' defects of dystrophin have normal ERGs, those with defects in the central region have a normal b-wave amplitude associated with prolonged implicit times for both the b-wave and oscillatory potentials, and mice with 3' defects have a phenotype similar to that seen in DMD/BMD patients. The mouse studies suggest a key role for the carboxyl terminal dystrophin isoform, Dp260, in retinal electrophysiology. We have undertaken a systematic evaluation of DMD/BMD patients through clinical examination and review of the literature in order to determine whether the position-specific effects of mutations noted in the mouse are present in man. We have found that, in man, a wider variation of DMD defects correlate with reductions in the b-wave amplitude. Individuals with normal ERGs have mutations predominantly located 5' of the transcript initiation site of Dp260. Our results suggest that the most important determinant in the ERG b-wave phenotype is the mutation position, rather than muscle disease severity. Forty-six per cent of patients with mutations 5' of the Dp260 transcript start site have abnormal ERGs, as opposed to 94% with more distal mutations. The human genotype-phenotype correlations are consistent with a role for Dp260 in normal retinal electrophysiology and may also reflect the expression of other C-terminal dystrophin isoforms and their contributions to retinal signal transmission.

Characterization of Mayven, a novel actin-binding protein predominantly expressed in brain

The cytoskeleton plays an important role in neuronal morphogenesis. We have identified and characterized a novel actin-binding protein, termed Mayven, predominantly expressed in brain. Mayven contains a BTB (broad complex, tramtrack, bric-a-brac)/POZ (poxvirus, zinc finger) domain-like structure in the predicted N terminus and "kelch repeats" in the predicted C-terminal domain. Mayven shares 63% identity (77% similarity) with the Drosophila ring canal ("kelch") protein. Somatic cell-hybrid analysis indicated that the human Mayven gene is located on chromosome 4q21.2, whereas the murine homolog gene is located on chromosome 8. The BTB/POZ domain of Mayven can self-dimerize in vitro, which might be important for its interaction with other BTB/POZ-containing proteins. Confocal microscopic studies of endogenous Mayven protein revealed a highly dynamic localization pattern of the protein. In U373-MG astrocytoma/glioblastoma cells, Mayven colocalized with actin filaments in stress fibers and in patchy cortical actin-rich regions of the cell margins. In primary rat hippocampal neurons, Mayven is highly expressed in the cell body and in neurite processes. Binding assays and far Western blotting analysis demonstrated association of Mayven with actin. This association is mediated through the "kelch repeats" within the C terminus of Mayven. Depolarization of primary hippocampal neurons with KCl enhanced the association of Mayven with actin. This increased association resulted in dynamic changes in Mayven distribution from uniform to punctate localization along neuronal processes. These results suggest that Mayven functions as an actin-binding protein that may be translocated along axonal processes and might be involved in the dynamic organization of the actin cytoskeleton in brain cells.