OBJECTIVE

Liver biopsy, the current clinical gold standard for fibrosis assessment, is invasive and has sampling errors, and is not optimal for screening, monitoring, or clinical decision-making. Fibrosis is characterized by excessive accumulation of extracellular matrix proteins including type I collagen. We hypothesize that molecular magnetic resonance imaging (MRI) with a probe targeted to type I collagen could provide a direct and non-invasive method of fibrosis assessment.

METHODS

Liver fibrosis was induced in rats with diethylnitrosamine and in mice with carbon tetrachloride. Animals were imaged prior to and immediately following i.v. administration of either collagen-targeted probe EP-3533 or non-targeted control Gd-DTPA. Magnetic resonance (MR) signal washout characteristics were evaluated from T1 maps and T1-weighted images. Liver tissue was subjected to pathologic scoring of fibrosis and analyzed for gadolinium and hydroxyproline.

RESULTS

EP-3533-enhanced MR showed greater signal intensity on delayed imaging (normalized signal enhancement mice: control=0.39 ± 0.04, fibrotic=0.55 ± 0.03, p<0.01) and slower signal washout in the fibrotic liver compared to controls (liver t(1/2)=51.3 ± 3.6 vs. 42.0 ± 2.5 min, p<0.05 and 54.5 ± 1.9 vs. 44.1 ± 2.9 min, p<0.01 for fibrotic vs. controls in rat and mouse models, respectively). Gd-DTPA-enhanced MR could not distinguish fibrotic from control animals. EP-3533 gadolinium concentration in the liver showed strong positive correlations with hydroxyproline levels (r=0.74 (rats), r=0.77 (mice)) and with Ishak scoring (r=0.84 (rats), r=0.79 (mice)).

CONCLUSIONS

Molecular MRI of liver fibrosis with a collagen-specific probe identifies fibrotic tissue in two rodent models of disease.

OBJECTIVE

We evaluated the face, content, and construct validity of what is, to our knowledge, the only available virtual reality simulator based on a complete kinematic representation of the da Vinci surgical system.

METHODS

A total of 5 experts (EPs) and 15 novices (NVs) completed exercises on the Mimic dV-Trainer (MdVT). All participants completed three repetitions of the following tasks: (1) Ring and Cone, (2) String Walk, and (3) Letterboard. Participants rated parameters of face and content validity on a five-point Likert-scale questionnaire. Workload imposed by the simulator was assessed using a NASA Task Load Index questionnaire (TLX).

RESULTS

Face validity of the MdVT was established as all 20 participants rated the simulator between average to easy-to-use and above-average to high in all parameters of realism. Participants in both EP and NV groups rated the MdVT's overall relevance to robotic surgery as very high. All five EPs assessed the simulator to be a very good practice format and very useful for training residents, thereby affirming content validity. A preliminary assessment of construct validity suggested that the MdVT could differentiate EPs from NVs. The overall TLX workload scores were lower in the EP group for all parameters except for temporal demand.

CONCLUSIONS

The MdVT demonstrated excellent face and content validity as well as reasonable workload parameters. The use of this simulator in resident training may help bridge the gap between the safe acquisition of surgical skills and effective performance during live robot-assisted surgery.

Erythropoietin (EP) is required by late-stage erythroid progenitor cells to prevent apoptosis. Several lines of evidence suggest that it is this action of EP that regulates erythrocyte production in vivo. To study the control of apoptosis in mouse and human erythroblasts, the expression of members of the Bcl-2 family of proteins and the expression and activation of the apoptosis-linked cysteine protease Yama/CPP32/apopain were examined. These proteins have been implicated as regulators of apoptosis in several cell models. The Bcl-2 family members analyzed were Bcl-2, Bcl-X, Bax, Bad, Bak, A1, and Mcl-1. Bcl-X expression in proerythroblasts was highly EP-dependent. Bcl-X was strongly increased during the terminal differentiation stages of human and mouse erythroblasts, reaching maximum transcript and protein levels at the time of maximum hemoglobin synthesis. This increase in Bcl-X expression led to an apparent level of approximately 50 times the level in proerythroblasts. In contrast, neither mouse nor human erythroblasts expressed Bcl-2 transcript or protein. Bax and Bad proteins remained relatively constant throughout differentiation, but diminished near the time of enucleation. Bak protein was present in early erythroblasts, but diminished progressively during differentiation. EP deprivation in both mouse and human erythroblasts led to activation of the cysteine protease, apopain, as was indicated by cleavage of the proenzyme into its proteolytically active fragments. Apopain activation was detectable within 2 hours of EP deprivation in mouse erythroblasts. These findings suggest an important role for Bcl-X in late erythroid differentiation and for apopain in apoptosis of erythroblasts caused by deprivation of EP.

Two inbred mouse strains, CBA/J and CBA/CaJ, have been used nearly interchangeably as 'good hearing' standards for research in hearing and deafness. We recently reported, however, that these two strains diverge after 1 year of age, such that CBA/CaJ mice show more rapid elevation of compound action potential (CAP) thresholds at high frequencies (Ohlemiller, Brain Res. 1277: 70-83, 2009). One contributor is progressive decline in endocochlear potential (EP) that appears only in CBA/CaJ. Here, we explore the cellular bases of threshold and EP disparities in old CBA/J and CBA/CaJ mice. Among the major findings, both strains exhibit a characteristic age (∼18 months in CBA/J and 24 months in CBA/CaJ) when females overtake males in sensitivity decline. Strain differences in progression of hearing loss are not due to greater hair cell loss in CBA/CaJ, but instead appear to reflect greater neuronal loss, plus more pronounced changes in the lateral wall, leading to EP decline. While both male and female CBA/CaJ show these pathologies, they are more pronounced in females. A novel feature that differed sharply by strain was moderate loss of outer sulcus cells (or 'root' cells) in spiral ligament of the upper basal turn in old CBA/CaJ mice, giving rise to deep indentations and void spaces in the ligament. We conclude that CBA/CaJ mice differ both quantitatively and qualitatively from CBA/J in age-related cochlear pathology, and model different types of presbycusis.

The brain mechanisms involved in processing another's physical pain have been extensively studied in recent years. The link between understanding others' physical pain and emotional suffering is less well understood. Using whole brain analysis and two separate functional localizers, we characterized the neural response profiles of narrative scenarios involving physical pain (PP), and scenarios involving emotional pain (EP) with functional magnetic resonance imaging (fMRI). Whole brain analyses revealed that PP narratives activated the Shared Pain network, and that the brain regions responsible for processing EP overlapped substantially with brain regions involved in Theory of Mind. Region of interest (ROI) analysis provided a finer-grained view. Some regions responded to stories involving physical states, regardless of painful content (secondary sensory regions), some selectively responded to both emotionally and physically painful events (bilateral anterior thalamus and anterior middle cingulate cortex), one brain region responded selectively to physical pain (left insula), and one brain region responded selectively to emotional pain (dorsomedial prefrontal cortex). These results replicated in two groups of participants given different explicit tasks. Together, these results clarify the distinct roles of multiple brain regions in responding to others who are in physical or emotional pain.

Non-invasive assessment of mechanical properties of the aorta may prove useful in the early detection of atheroma. We have evaluated several of the available echocardiographic indices using ability to detect age-related changes in putatively disease-free vessels as a measure of sensitivity to changes in aortic mechanical properties. Suprasternal imaging was used in 49 healthy non-smoking volunteers to measure minimum and maximum aortic arch diameters. Maximal flow velocities, with corresponding acceleration times and heart periods, were determined in the descending aorta in 24 of these subjects. Blood pressure was recorded non-invasively immediately after the echocardiographic study. Doppler derived measurements of aortic flow acceleration did not relate to age (P greater than 0.05). Three different 2D echo assessments of aortic distensibility, however, all showed a close relationship to age. Ep elastic modulus and Beta index (derived from different stress-strain mechanical relationships) were significantly related to age with r = 0.69 and 0.65 respectively. There were no significant effects of gender or left ventricular systolic function on these relationships. There was a tendency for the relationship between these distensibility indices and age more closely to fit an exponential than a linear relationship. We conclude that 2D echocardiographic assessment of aortic distensibility is able to detect sensitively changes in aortic mechanical properties. Even in the absence of risk factors for cardiovascular disease there is a marked reduction in aortic distensibility with increasing age.

OBJECTIVE

Arterial stiffness may indicate early vascular changes that predispose to the development of major vascular disease. The repeatability of a variety of indices of arterial stiffness calculated from a standard carotid arterial M-mode ultrasound image was investigated.

METHODS

Twenty-six asymptomatic normal subjects were imaged and had blood pressure recordings on each of two separate occasions at least 1 day apart. Using a computer-assisted method, the maximum and minimum internal diameter and average wall thickness of the right common carotid artery were measured over several cardiac cycles, and the following indices of arterial stiffness and distensibility (compliance) were derived: the pressure-strain elastic modulus (Ep), Young's modulus (E), cross-sectional compliance (CC), and the distensibility coefficient (DC).

RESULTS

The repeatability of these measures, expressed as coefficients of variation, was as follows: Ep, 18%; E, 24%; CC, 14%; and DC, 13%. In another group of 20 subjects, the coefficient of variation for repeat examination by different sonographers was Ep, 19%; E, 20%; CC, 14%; and DC, 17% and for the one sonographer using two ultrasound machines was Ep, 13%; E, 13%; CC, 11%; and DC, 13%. These values indicate a moderate level of repeatability. In a univariate analysis each of these indices was significantly related to increasing age (Ep = 1.0 + 12.9 x AGE, r = .80; E = 314.5 + 13.9 x AGE, r = .48; CC = 22.6-0.26 x AGE, r = -.63; DC = 64.0-0.65 x AGE, r = -.78) but not to wall thickness (all P>> .47). Using multiple regression techniques to adjust for age, wall thickness is a significant predictor of distensibility (P = .017), cross-sectional compliance (P < .001), and the pressure-strain elastic modulus (P = .019). Because Young's modulus is calculated from wall thickness, it could not be included in the multivariate analysis.

CONCLUSIONS

We conclude that estimates of carotid artery distensibility and cross-sectional compliance derived from M-mode ultrasound recordings are moderately repeatable and may provide useful additional end points for trials of atherosclerotic progression.

Impairments in neuropsychological functioning have been described in subjects clinically at high risk for psychosis, but the specific cognitive deficits in different clinical high-risk groups remain to be elucidated. The German Research Network on Schizophrenia employs a heuristic 2-stage model: a putatively late prodromal state (LPS), characterized by the onset of attenuated positive or brief psychotic symptoms, and an early prodromal state (EPS), mainly characterized by the presence of basic symptoms, which are predictive for psychosis within the next 10 years. A total of 205 subjects met the criteria for either an EPS or an LPS of psychosis and were assessed with a comprehensive neuropsychological test battery. Neurocognitive profiles of high-risk groups were compared with data of 87 healthy controls comparable with regard to gender, age, and premorbid verbal IQ. Patients in the LPS were impaired in all neurocognitive domains (memory/learning, executive control/processing speed, and working memory) examined, with memory being the worst. Deficits were less pronounced in patients in the EPS, with a specific deficit in the executive control/processing speed domain. Consistent with a progressive neurodevelopmental disorder, some cognitive abilities were already impaired in patients in the EPS, followed by further deterioration in the LPS. Specifically, deficits in executive control functioning were related to the presence of basic symptoms, indicating a vulnerability for psychosis. Memory deficits were associated with the onset of psychotic symptoms indicating further disease progression in the trajectory to psychosis and, thus, may be useful in predicting psychosis and targeting early intervention.

OBJECTIVE

To test the reproducibility of model-derived quantitative and semiquantitative pharmacokinetic parameters among various commercially available perfusion analysis solutions for dynamic contrast material-enhanced (DCE) magnetic resonance (MR) imaging.

METHODS

The study was institutional review board approved and HIPAA compliant, with waiver of informed consent granted. The study group consisted of 15 patients (mean age, 44 years; range, 28-60 years), with 15 consecutive 1.5-T DCE MR imaging studies performed between October 1, 2010, and December 27, 2010, prior to uterine fibroid embolization. Studies were conducted by using variable-flip-angle T1 mapping and four-dimensional, time-resolved MR angiography with interleaved stochastic trajectories. Images from all DCE MR imaging studies were postprocessed with four commercially available perfusion analysis solutions by using a Tofts and Kermode model paradigm. Five observers measured pharmacokinetic parameters (volume transfer constant [K(trans)], v(e) [extracellular extravascular volume fraction], k(ep)[K(trans)/v(e)], and initial area under the gadolinium curve [iAUGC]) three times for each imaging study with each perfusion analysis solution (between March 13, 2011, and September 8, 2011) by using two different region-of-interest methods, resulting in 1800 data points.

RESULTS

After normalization of data output, significant differences in mean values were found for the majority of perfusion analysis solution combinations. The within-subject coefficient of variation among perfusion analysis solutions was 48.3%-68.8% for K(trans), 37.2%-60.3% for k(ep), 27.7%-74.1% for v(e), and 25.1%-61.2% for iAUGC. The intraclass correlation coefficient revealed only poor to moderate consistency among pairwise perfusion analysis solution comparisons (K(trans), 0.33-0.65; k(ep), 0.02-0.81; v(e), -0.03 to 0.72; and iAUGC, 0.47-0.78).

CONCLUSIONS

A considerable variability for DCE MR imaging pharmacokinetic parameters (K(trans), k(ep), v(e), iAUGC) was found among commercially available perfusion analysis solutions. Therefore, clinical comparability across perfusion analysis solutions is currently not warranted. Agreement on a postprocessing standard is paramount prior to establishing DCE MR imaging as a widely incorporated biomarker.

Risperidone is a recently introduced neuroleptic distinguished by a decreased incidence of extrapyramidal side effects (EPS). The mechanism of its low EPS is unclear. Since it has been shown that EPS is related to the level of D2 receptor occupancy, we studied nine patients receiving 2-6 mg/day of risperidone using [11C]-raclopride PET scans in order to determine the in vivo D2 receptor binding characteristics of risperidone. The mean level of receptor occupancy was 66% at 2 mg; 73% at 4 mg; and 79% at 6 mg. Three patients, those with the highest receptor occupancies, exhibited mild EPS, though none required anitparkinsonian medications. Our results suggest that at doses of 4-6 mg the in vivo D2 receptor occupancy of risperidone is similar to that of typical neuroleptics and higher than that of clozapine. This would suggest that the EPS benefits of risperidone cannot be explained by a low D2 binding but may be related to its high 5-HT2 affinity. However, the emergence of EPS at higher levels of D2 receptor occupancy, in this study and in previous clinical trials, would suggest that risperidone's high 5-HT2 affinity provides only a relative protection from EPS. And once the D2 occupancy exceeds a certain threshold this 'relative' 5-HT2-mediated protection from EPS may be lost.

The prostate gland secretes many proteins in a prostatic fluid that combines with seminal vesicle derived fluids to promote sperm activation and function. Proximal fluids of the prostate that can be collected clinically are seminal plasma and expressed-prostatic secretion (EPS) fluids. EPS represents the fluid being secreted by the prostate following a digital rectal prostate massage, which in turn can be collected in voided urine post-exam. This collection is not disruptive to a standard urological exam, and it can be repeatedly collected from men across all prostatic disease states. A direct EPS fluid can also be collected under anesthesia prior to prostatectomy. While multiple genetic assays for prostate cancer detection are being developed for the shed epithelial cell fraction of EPS urines, the remaining fluid that contains many prostate-derived proteins has been minimally characterized. Approaches to optimization and standardization of EPS collection consistent with current urological exam and surgical practices are described, and initial proteomic and glycomic evaluations of the of EPS fluid are summarized for prostate specific antigen and prostatic acid phosphatase. Continued characterization of the prostate specific protein components of EPS urine combined with optimization of clinical collection procedures should facilitate discovery of new biomarkers for prostate cancer.

OBJECTIVE

In recent years, the detection of even a few tumor cells in lymph nodes of patients with surgically resected non-small-cell lung cancer (NSCLC) became possible with immunohistochemical staining procedures. Tumor cells in lymph nodes have been shown to be associated with an increased rate of early recurrence. However, the prognostic significance of this minimal tumor cell spread for overall survival remains unclear.

METHODS

We used the epithelium-specific monoclonal antibody Ber-EP4, which recognizes the 17-1A antigen (also called EGP40 or Ep-CAM), to discover small tumor cell deposits (< or = three cells) in 565 regional lymph nodes judged as tumor-free by conventional histopathology in patients with NSCLC staged as pT1-4, pN0-2, M0, R0. In a prospective analysis, we studied the influence of the detected tumor cells on the cancer recurrence rate and survival of 117 patients.

RESULTS

Ber-EP4-positive cells were found in 27 of 125 patients (21.6%). After an observation period of 64 months, patients with disseminated tumor cells had reduced disease-free survival (P < .0001) and overall survival (P = .0001) rates in univariate analyses (logrank test). Multivariate analysis (Cox model) showed a 2.7 times increased risk for tumor relapse and a 2.5 times increased risk for shorter survival in patients with disseminated tumor cells compared with patients without such cells. Patients without any evidence of histopathologic and immunohistochemical lymph node involvement had an overall survival rate of 78%.

CONCLUSIONS

The immunohistochemical detection of disseminated tumor cells in lymph nodes of patients with completely resected NSCLC is an independent prognostic factor for overall survival.

UNASSIGNED

Despite apparent progress in perinatal care, children born extremely or very preterm (EP/VP) remain at high risk for cognitive deficits. Insight into factors contributing to cognitive outcome is key to improve outcomes after EP/VP birth.

UNASSIGNED

To examine the cognitive abilities of children of EP/VP birth (EP/VP children) and the role of perinatal and demographic risk factors.

UNASSIGNED

PubMed, Web of Science, and PsycINFO were searched without language restriction (last search March 2, 2017). Key search terms included preterm, low birth weight, and intelligence.

UNASSIGNED

Peer-reviewed studies reporting intelligence scores of EP/VP children (<32 weeks of gestation) and full-term controls at age 5 years or older, born in the antenatal corticosteroids and surfactant era, were included. A total of 268 studies met selection criteria, of which 71 covered unique cohorts.

UNASSIGNED

MOOSE guidelines were followed. Data were independently extracted by 2 researchers. Standardized mean differences in intelligence per study were pooled using random-effects meta-analysis. Heterogeneity in effect size across studies was studied using multivariate, random-effects meta-regression analysis.

UNASSIGNED

Primary outcome was intelligence. Covariates included gestational age, birth weight, birth year, age at assessment, sex, race/ethnicity, socioeconomic status, small for gestational age, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia (BPD), necrotizing enterocolitis, sepsis, and postnatal corticosteroid use.

UNASSIGNED

The 71 included studies comprised 7752 EP/VP children and 5155 controls. Median gestational age was 28.5 weeks (interquartile range [IQR], 2.4 weeks) and the mean age at assessment ranged from 5.0 to 20.1 years. The median proportion of males was 50.0% (IQR, 8.7%). Preterm children had a 0.86-SD lower IQ compared with controls (95% CI, -0.94 to -0.78, P < .001). Results were heterogeneous across studies (I2 = 74.13; P < .001). This heterogeneity could not be explained by birth year of the cohort. Multivariate meta-regression analysis with backward elimination revealed that BPD explained 65% of the variance in intelligence across studies, with each percent increase in BPD rate across studies associated with a 0.01-SD decrease in IQ (0.15 IQ points) (P < .001).

UNASSIGNED

Extremely or very preterm children born in the antenatal corticosteroids and surfactant era show large deficits in intelligence. No improvement in cognitive outcome was observed between 1990 and 2008. These findings emphasize that improving outcomes after EP/VP birth remains a major challenge. Bronchopulmonary dysplasia was found to be a crucial factor for cognitive outcome. Lowering the high incidence of BPD may be key to improving long-term outcomes after EP/VP birth.

We have generated a cell line (F cells) producing a secreted form of Japanese encephalitis virus (JEV) subviral particle (extracellular particles [EPs]) that contains the JEV envelope glycoprotein (E) and a precursor (prM) of the virion membrane protein (M). The F cells were engineered to synthesize these JEV products from a cDNA encoding a mutated (furin proteinase resistant) form of prM, since stable cell lines expressing E and the authentic form of prM could not be obtained, due (in part) to the cell-fusing ability of EPs containing E and M. Our biochemical alteration of the prM protein was critical for the successful production of EP-producing cell lines. EPs produced by F cells share the biochemical properties of empty viral particles produced by JEV-infected cells, except that the F-cell EPs lack hemagglutinating activity and M. F-cell EPs were recognized by a panel of monoclonal antibodies to E, and EPs were shown to be useful as vaccine candidates in mice and as diagnostic reagents in evaluating human immune responses to JE vaccination. The amounts of E antigen released into the culture fluid of F cells were similar to those found in virion fractions of JEV-infected cell culture fluids or JEV-infected weanling mouse brains (the current source of antigen used to produce human vaccines for JE). Thus, the F-cell line would appear to be a useful source of antigen for JE vaccines and diagnostics.

Stem cells are critical in maintaining adult homeostasis and have been proposed to be the origin of many solid tumors, including pancreatic cancer. Here we demonstrate the expression patterns of the putative intestinal stem cell marker DCAMKL-1 in the pancreas of uninjured C57BL/6 mice compared with other pancreatic stem/progenitor cell markers. We then determined the viability of isolated pancreatic stem/progenitor cells in isotransplantation assays following DCAMKL-1 antibody-based cell sorting. Sorted cells were grown in suspension culture and injected into the flanks of athymic nude mice. Here we report that DCAMKL-1 is expressed in the main pancreatic duct epithelia and islets, but not within acinar cells. Coexpression was observed with somatostatin, NGN3, and nestin, but not glucagon or insulin. Isolated DCAMKL-1+ cells formed spheroids in suspension culture and induced nodule formation in isotransplantation assays. Analysis of nodules demonstrated markers of early pancreatic development (PDX-1), glandular epithelium (cytokeratin-14 and Ep-CAM), and isletlike structures (somatostatin and secretin). These data taken together suggest that DCAMKL-1 is a novel putative stem/progenitor marker, can be used to isolate normal pancreatic stem/progenitors, and potentially regenerates pancreatic tissues. This may represent a novel tool for regenerative medicine and a target for anti-stem cell-based therapeutics in pancreatic cancer.

The hybrid sensor kinase RpfC positively regulates the expression of a range of virulent genes and negatively modulates the synthesis of the quorum sensing signal diffusible signal factor (DSF) in Xanthomonas campestris. Three conserved amino acid residues of RpfC implicated in phosphorelay (His(198) in the histidine kinase domain, Asp(512) in the receiver domain, and His(657) in the histidine phosphotransfer domain) were essential for activation of the production of extracellular enzymes and extracellular polysaccharide (EPS) virulence factors but were not essential for repression of DSF biosynthesis. Domain deletion and subsequent in trans expression analysis revealed that the receiver domain of RpfC alone was sufficient to repress DSF overproduction in an rpfC deletion mutant. Further deletion and alanine scanning mutagenesis analyses identified a peptide of 107 amino acids and three amino acid residues (Gln(496), Glu(504), and Ile(552)) involved in modulating DSF production. Co-immunoprecipitation and far Western blot analyses suggested an interaction between the receiver domain and RpfF, the enzyme involved in DSF biosynthesis. These data support a model in which RpfC modulates two different functions (virulence factor synthesis and DSF synthesis) by utilization of a conserved phosphorelay system and a novel domain-specific protein-protein interaction mechanism, respectively. This latter mechanism represents an added dimension to conventional two-component signaling paradigms.

BACKGROUND

Proteolytic cleavage of the extracellular domain (EpEx) of Epithelial cell adhesion molecule (EpCAM) and nuclear signaling by its intracellular oncogenic domain Ep-ICD has recently been implicated in increased proliferation of cancer cells. The clinical significance of Ep-ICD in human tumors remains an enigma.

METHODS

EpEx, Ep-ICD and beta-catenin immunohistochemistry using specific antibodies was conducted on 58 archived thyroid cancer (TC) tissue blocks from 34 patients and correlated with survival analysis of these patients for up to 17 years.

RESULTS

The anaplastic (ATC) and aggressive thyroid cancers showed loss of EpEx and increased nuclear and cytoplasmic accumulation of Ep-ICD. In contrast, the low grade papillary thyroid cancers (PTC) showed membranous EpEx and no detectable nuclear Ep-ICD. The ATC also showed concomitant nuclear expression of Ep-ICD and beta-catenin. Kaplan-Meier Survival analysis revealed reduced overall survival (OS) for TC patients showing nuclear Ep-ICD expression or loss of membranous EpEx (p < 0.0004), median OS = 5 months as compared to 198 months for patients who did not show nuclear Ep-ICD or demonstrated only membranous EpE.

CONCLUSIONS

We report reciprocal loss of membrane EpEx but increased nuclear and cytoplasmic accumulation of Ep-ICD in aggressive TC; nuclear Ep-ICD correlated with poor OS of TC patients. Thus nuclear Ep-ICD localization may serve as a useful biomarker for aggressive TC and may represent a novel diagnostic, prognostic and therapeutic target for aggressive TC.

Embryo implantation into receptive endometrium requires synergistic endometrial-blastocyst interactions within the uterine cavity and is essential for establishing pregnancy. We demonstrate that exosomes (40-150 nm nanovesicles) released from endometrial epithelial cells are an important component of these interactions. We defined the proteome of purified endometrial epithelial-derived exosomes (Exos) influenced by menstrual cycle hormones estrogen (E; proliferative phase) and estrogen plus progesterone (EP; receptive phase) and examined their potential to modify trophoblast function. E-/EP-Exos were uniquely enriched with 254 and 126 proteins, respectively, with 35% newly identified proteins not previously reported in exosome databases. Importantly, EP-Exos protein cargo was related to fundamental changes in implantation: adhesion, migration, invasion, and extracellular matrix remodeling. These findings from hormonally treated ECC1 endometrial cancer cells were validated in human primary uterine epithelial cell-derived exosomes. Functionally, exosomes were internalized by human trophoblast cells and enhanced their adhesive capacity, a response mediated partially through active focal adhesion kinase (FAK) signaling. Thus, exosomes contribute to the endometrial-embryo interactions within the human uterine microenvironment essential for successful implantation.

BACKGROUND

Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of rice bacterial blight disease. Xoo produces a range of virulence factors, including EPS, extracellular enzyme, iron-chelating siderophores, and type III-secretion dependent effectors, which are collectively essential for virulence. Genetic and genomics evidence suggest that Xoo might use the diffusible signal factor (DSF) type quorum sensing (QS) system to regulate the virulence factor production. However, little is known about the chemical structure of the DSF-like signal(s) produced by Xoo and the factors influencing the signal production.

RESULTS

Xoo genome harbours an rpf cluster comprising rpfB, rpfF, rpfC and rpfG. The proteins encoded by these genes are highly homologous to their counterparts in X. campestris pv. campestris (Xcc), suggesting that Xcc and Xoo might use similar mechanisms for DSF biosynthesis and autoregulation. Consistent with in silico analysis, the rpfF mutant was DSF-deficient and the rpfC mutant produced about 25 times higher DSF-like activity than the wild type Xoo strain KACC10331. From the supernatants of rpfC mutant, we purified three compounds showing strong DSF-like activity. Mass spectrometry and NMR analysis revealed that two of them were the previously characterized DSF and BDSF; the third one was a novel unsaturated fatty acid with 2 double bonds and was designated as CDSF in this study. Further analysis showed that all the three DSF-family signals were synthesized via the enzyme RpfF encoded by Xoo2868. DSF and BDSF at a final concentration of 3 microM to the rpfF mutant could fully restore its extracellular xylanase activity and EPS production to the wild type level, but CDSF was less active than DSF and BDSF in induction of EPS and xylanase. DSF and CDSF shared a similar cell density-dependent production time course with the maximum production being detected at 42 h after inoculation, whereas the maximum production of BDSF was observed at 36 h after inoculation. When grown in a rich medium such as YEB, LB, PSA, and NYG, Xoo produced all the three signals with the majority being DSF. Whereas in nutritionally poor XOLN medium Xoo only produced BDSF and DSF but the majority was BDSF.

CONCLUSIONS

This study demonstrates that Xoo and Xcc share the conserved mechanisms for DSF biosynthesis and autoregulation. Xoo produces DSF, BDSF and CDSF signals in rich media and CDSF is a novel signal in DSF-family with two double bonds. All the three DSF-family signals promote EPS production and xylanase activity in Xoo, but CDSF is less active than its analogues DSF and BDSF. The composition and ratio of the three DSF-family signals produced by Xoo are influenced by the composition of culture media.

OBJECTIVE

The objective was to perform an epidemiologic study of emergency department (ED) medical malpractice claims using data maintained by the Physician Insurers Association of America (PIAA), a trade association whose participating malpractice insurance carriers collectively insure over 60% of practicing physicians in the United States.

METHODS

All closed malpractice claims in the PIAA database between 1985 and 2007, where an event in an ED was alleged to have caused injury to a patient 18 years of age or older, were retrospectively reviewed. Study outcomes were the frequency of claims and average indemnity payments associated with specific errors identified by the malpractice insurer, as well as associated health conditions, primary specialty groups, and injury severity. Indemnity payments include money paid to claimants as a result of settlement or court adjudication, and this financial obligation to compensate a claimant constitutes the insured's financial liability. These payments do not include the expenses associated with resolving a claim, such as attorneys' fees. The study examined claims by adjudicatory outcome, associated financial liability, and expenses of litigation. Adjudicatory outcome refers to the legal disposition of a claim as it makes its way into and through the court system and includes resolution of claims by formal verdict as well as by settlement. The study also investigated how the number of claims, average indemnity payments, paid-to-close ratios (the percentage of closed claims that resolved with a payment to the plaintiff), and litigation expenses have trended over the 23-year study period.

RESULTS

The authors identified 11,529 claims arising from an event originating in an ED, representing over $664 million in total liability over the 23-year study period. Emergency physicians (EPs) were the primary defendants in 19% of ED claims. The largest sources of error, as identified by the individual malpractice insurer, included errors in diagnosis (37%), followed by improper performance of a procedure (17%). In 18% of claims, no error could be identified by the insurer. Acute myocardial infarction (AMI; 5%), fractures (6%), and appendicitis (2%) were the health conditions associated with the highest number of claims. Over two-thirds of claims (70%) closed without payment to the claimant. Most claims that paid out did so through settlement (29%). Only 7% of claims were resolved by verdict, and 85% of those were in favor of the clinician. Over time, the average indemnity payments and expenses of litigation, adjusted for inflation, more than doubled, while both the total number of claims and number of paid claims decreased.

CONCLUSIONS

Emergency physicians were the primary defendants in a relatively small proportion of ED claims. The disease processes associated with the highest numbers of claims included AMI, appendicitis, and fractures. The largest share of overall indemnity was attributed to errors in the diagnostic process. The financial liability of medical malpractice in the ED is substantial, yet the vast majority of claims resolve in favor of the clinician. Efforts to mitigate risk in the ED should include the diverse clinical specialties who work in this complex environment, with attention to those health conditions and potential errors with the highest risk.

OBJECTIVE

To investigate methods developed for the characterisation of the morphology and enhancement kinetic features of both mass and non-mass lesions, and to determine their diagnostic performance to differentiate between malignant and benign lesions that present as mass versus non-mass types.

METHODS

Quantitative analysis of morphological features and enhancement kinetic parameters of breast lesions were used to differentiate among four groups of lesions: 88 malignant (43 mass, 45 non-mass) and 28 benign (19 mass, 9 non-mass). The enhancement kinetics was measured and analysed to obtain transfer constant (K(trans)) and rate constant (k(ep)). For each mass eight shape/margin parameters and 10 enhancement texture features were obtained. For the lesions presenting as nonmass-like enhancement, only the texture parameters were obtained. An artificial neural network (ANN) was used to build the diagnostic model.

RESULTS

For lesions presenting as mass, the four selected morphological features could reach an area under the ROC curve (AUC) of 0.87 in differentiating between malignant and benign lesions. The kinetic parameter (k(ep)) analysed from the hot spot of the tumour reached a comparable AUC of 0.88. The combined morphological and kinetic features improved the AUC to 0.93, with a sensitivity of 0.97 and a specificity of 0.80. For lesions presenting as non-mass-like enhancement, four texture features were selected by the ANN and achieved an AUC of 0.76. The kinetic parameter k(ep) from the hot spot only achieved an AUC of 0.59, with a low added diagnostic value.

CONCLUSIONS

The results suggest that the quantitative diagnostic features can be used for developing automated breast CAD (computer-aided diagnosis) for mass lesions to achieve a high diagnostic performance, but more advanced algorithms are needed for diagnosis of lesions presenting as non-mass-like enhancement.

BACKGROUND

This trial was designed to prove superiority of irinotecan over etoposide combined with carboplatin in extensive-disease small-cell lung cancer.

METHODS

Patients were randomly assigned to receive carboplatin area under the curve 5 mg x min/ml either in combination with irinotecan 50 mg/m2 on days 1, 8, and 15 (IP) or etoposide 140 mg/m2 on days 1-3 (EP). Primary end point was progression-free survival (PFS) at 6 months. Secondary end points were overall survival (OS), response rate, and toxicity.

RESULTS

Of 226 patients, 216 were eligible. Median PFS was 6.0 months [95% confidence interval (CI) 5.0-7.0] in the IP arm and 6.0 months (95% CI 5.2-6.8) in EP arm (P = 0.07). Median survival was 10.0 months (95% CI 8.4-11.6) and 9.0 months (95% CI 7.6-10.4) in the IP and EP arm (P = 0.06), respectively. Hazard ratios for disease progression and OS were 1.29 (95% CI 0.96-1.73, P = 0.095) and 1.34 (95% CI 0.97-1.85, P = 0.072), respectively. No difference in response rates was observed. Grade 3 and 4 hematologic toxicity favored the IP arm, whereas diarrhea was significantly more frequent in the IP arm.

CONCLUSIONS

This trial failed to show superiority of irinotecan over etoposide in combination with carboplatin.

We studied thorax formation in Drosophila melanogaster using a misexpression screen with EP lines and thoracic Gal4 drivers that provide a genetically sensitized background. We identified 191 interacting lines showing alterations of thoracic bristles (number and/or location), thorax and scutellum malformations, lethality, or suppression of the thoracic phenotype used in the screen. We analyzed these lines and showed that known genes with different functional roles (selector, prepattern, proneural, cell cycle regulation, lineage restriction, signaling pathways, transcriptional control, and chromatin organization) are among the modifier lines. A few lines have previously been identified in thorax formation, but others, such as chromatin-remodeling complex genes, are novel. However, most of the interacting loci are uncharacterized, providing a wealth of new genetic data. We also describe one such novel line, poco pelo (ppo), where both misexpression and loss-of-function phenotypes are similar: loss of bristles and scutellum malformation.

The Protein Structure Initiative:Biology-Materials Repository (PSI:Biology-MR; MR; http://psimr.asu.edu ) sequence-verifies, annotates, stores, and distributes the protein expression plasmids and vectors created by the Protein Structure Initiative (PSI). The MR has developed an informatics and sample processing pipeline that manages this process for thousands of samples per month from nearly a dozen PSI centers. DNASU ( http://dnasu.asu.edu ), a freely searchable database, stores the plasmid annotations, which include the full-length sequence, vector information, and associated publications for over 130,000 plasmids created by our laboratory, by the PSI and other consortia, and by individual laboratories for distribution to researchers worldwide. Each plasmid links to external resources, including the PSI Structural Biology Knowledgebase ( http://sbkb.org ), which facilitates cross-referencing of a particular plasmid to additional protein annotations and experimental data. To expedite and simplify plasmid requests, the MR uses an expedited material transfer agreement (EP-MTA) network, where researchers from network institutions can order and receive PSI plasmids without institutional delays. As of March 2011, over 39,000 protein expression plasmids and 78 empty vectors from the PSI are available upon request from DNASU. Overall, the MR's repository of expression-ready plasmids, its automated pipeline, and the rapid process for receiving and distributing these plasmids more effectively allows the research community to dissect the biological function of proteins whose structures have been studied by the PSI.