172 research outputs found
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Transcriptional profiling of the LPS induced NF-κB response in macrophages
BACKGROUND: Exposure of macrophages to bacterial products such as lipopolysaccharide (LPS) results in activation of the NF-κB transcription factor, which orchestrates a gene expression programme that underpins the macrophage-dependent immune response. These changes include the induction or repression of a wide range of genes that regulate inflammation, cell proliferation, migration and cell survival. This process is tightly regulated and loss of control is associated with conditions such as septic shock, inflammatory diseases and cancer. To study this response, it is important to have in vitro model systems that reflect the behaviour of cells in vivo. In addition, it is necessary to understand the natural differences that can occur between individuals. In this report, we have investigated and compared the LPS response in macrophage derived cell lines and peripheral blood mononuclear cell (PBMC) derived macrophages. RESULTS: Gene expression profiles were determined following LPS treatment of THP-1 cells for 1 and 4 hours. LPS significantly induced or repressed 72 out of 465 genes selected as being known or putative NF-κB target genes, which exhibited 4 temporal patterns of expression. Results for 34 of these genes, including several genes not previously identified as LPS target genes, were validated using real time PCR. A high correlation between microarray and real time PCR data was found. Significantly, the LPS induced expression profile of THP-1 cells, as determined using real time PCR, was found to be very similar to that of human PBMC derived macrophages. Interestingly, some differences were observed in the LPS response between the two donor PBMC macrophage populations. Surprisingly, we found that the LPS response in U937 cells was dramatically different to both THP-1 and PBMC derived macrophages. CONCLUSION: This study revealed a dynamic and diverse transcriptional response to LPS in macrophages, involving both the induction and repression of gene expression in a time dependent manner. Moreover, we demonstrated that the LPS induced transcriptional response in the THP-1 cell line is very similar to primary PBMC derived macrophages. Therefore, THP-1 cells represent a good model system for studying the mechanisms of LPS and NF-κB dependent gene expression
Atmospheric monitoring for the Pembina Cardium CO2 Monitoring Project using open path laser technology
AbstractThis study aimed to assess remote sensing methods using open path laser technology as a tool for atmospheric monitoring of CO2 storage sites. CH4 and CO2 open path detection systems were tested at the Penn West Pembina Cardium CO2 enhanced oil recovery monitoring pilot. The tested CH4 detection system was found to be very sensitive and small increases in the gas concentration due to controlled releases were easily distinguishable. The detection capability of the CO2 detection system was impacted by the larger natural background concentration of CO2. Where possible, CH4 should be used as an indicator due to the better detection capabilities and smaller background concentration variations compared to CO2
Treatment utilization and outcomes in elderly patients with locally advanced esophageal carcinoma: A review of the National Cancer Database
For elderly patients with locally advanced esophageal cancer, therapeutic approaches and outcomes in a modern cohort are not well characterized. Patients ≥70 years old with clinical stage II and III esophageal cancer diagnosed between 1998 and 2012 were identified from the National Cancer Database and stratified based on treatment type. Variables associated with treatment utilization were evaluated using logistic regression and survival evaluated using Cox proportional hazards analysis. Propensity matching (1:1) was performed to help account for selection bias. A total of 21,593 patients were identified. Median and maximum ages were 77 and 90, respectively. Treatment included palliative therapy (24.3%), chemoradiation (37.1%), trimodality therapy (10.0%), esophagectomy alone (5.6%), or no therapy (12.9%). Age ≥80 (OR 0.73), female gender (OR 0.81), Charlson-Deyo comorbidity score ≥2 (OR 0.82), and high-volume centers (OR 0.83) were associated with a decreased likelihood of palliative therapy versus no treatment. Age ≥80 (OR 0.79) and Clinical Stage III (OR 0.33) were associated with a decreased likelihood, while adenocarcinoma histology (OR 1.33) and nonacademic cancer centers (OR 3.9), an increased likelihood of esophagectomy alone compared to definitive chemoradiation. Age ≥80 (OR 0.15), female gender (OR 0.80), and non-Caucasian race (OR 0.63) were associated with a decreased likelihood, while adenocarcinoma histology (OR 2.10) and high-volume centers (OR 2.34), an increased likelihood of trimodality therapy compared to definitive chemoradiation. Each treatment type demonstrated improved survival compared to no therapy: palliative treatment (HR 0.49) to trimodality therapy (HR 0.25) with significance between all groups. Any therapy, including palliative care, was associated with improved survival; however, subsets of elderly patients with locally advanced esophageal cancer are less likely to receive aggressive therapy. Care should be taken to not unnecessarily deprive these individuals of treatment that may improve survival
Trapped in a disrupted normality : survivors' and partners' experiences of life after a sudden cardiac arrest
Aim of the study
Advances in resuscitation science have resulted in a growing number of out-of-hospital cardiac arrest (OHCA) survivors. However, we know very little about the natural history of recovery and the unmet needs of survivors and their partners. This qualitative study sought to address this knowledge gap to improve understanding of the consequences of surviving cardiac arrest.
Methods
In-depth qualitative interviews were undertaken separately with survivors and their partners between 3 and 12-months following the cardiac arrest. An interpretative phenomenological approach (IPA) to data analysis was adopted. Developing themes were discussed between members of the research team.
Results
8 survivors (41–79 years; 5 male; mean time 6.3 months post-hospital discharge) and 3 partners (1 male) were interviewed. The key (super-ordinate) theme of being ‘trapped in a disrupted normality’ was identified within the data. Five related subordinate themes included: existential impact, physical ramifications, emotional consequences, limiting participation in social activities and altered family roles.
Conclusion
Recovery for survivors is hindered by a wide range of physical, emotional, cognitive, social and spiritual challenges that disrupt perceptions of ‘normality’. Survivors and their carers may benefit from focussing on establishing a ‘new normal’ rather than striving to achieve a pre-cardiac social and physical position. Survivor-centred assessment should support rather than undermine this goal
Influence of microRNAs from Semen on Bovine Fertility
The objective of this study was to compare the miRNAs within sperm cells of bulls considered to have high and low fertility
Differences in Relative Abundance of GnRH-I and GnRH-II in Granulosa Cells of Bovine Antral Follicles at Specific Stages of Follicular Development
Increased estradiol is the primary signal to initiate standing estrus, and cows that exhibit estrus prior to fixed-time artificial insemination have greater pregnancy rates than cows that do not. Therefore, understanding what factors may be present at the ovary that may regulate estradiol production is critical. A previous study reported that bovine follicles with greater follicular fluid concentrations of estradiol had decreased expression of GnRH-I and GnRH-II in granulosa cells (GC). The objective of this study was to characterize relative abundance of GnRH-I and -II mRNA within GC of follicles at specific stages of development. Beef cows were synchronized, and ovaries were collected at specific stages of follicular development [pre-selection (PRE), post-selection (POST), and post-selection 24 h after luteal regression (POST-PG)]. All surface follicles were classified as small (\u3c 5mm), medium (5 - 8mm), or large (\u3e 8mm) and aspirated to collect GC. Large follicles from each animal were kept separate and all other follicles were pooled by size within animal (n = 27, 27, and 18 for small, medium, and large). Total cellular RNA was extracted, and RT-PCR was performed for GnRH-I, GnRH-II, and GAPDH. Data were analyzed using the MIXED procedure of SAS. Across all follicles, GnRH-I and GnRH-II expression were not influenced by stage (P = 0.27) but were influenced by size (P \u3c 0.01). Smalls (4.55 ± 0.39 and 3.91 ± 0.44, respectively) had greater expression (P ≤ 0.01) of GnRH compared to mediums (0.83 ± 0.39 and 1.41 ± 0.44, respectively) and larges (0.52 ± 0.47 and 2.12 ± 0.54, respectively). There was also a stage by size interaction (P \u3c 0.01). POST (P \u3c 0.01) and POST-PG (P ≤ 0.08) smalls had or tended to have increased expression compared to PRE smalls, but PRE mediums had increased expression (P \u3c 0.03) compared to POST-PG mediums. When only the largest follicle for each animal was evaluated, stage of development influenced expression of GnRH-I (P = 0.03) but not GnRH-II (P = 0.91). For GnRH-I, PRE tended (P = 0.09; 2.29 ± 0.55) to have increased expression compared to POST (0.92 ± 0.55) and did have greater expression compared to POST-PG (P = 0.01; 0.11 ± 0.55). Thus, GnRH within antral follicles may be a key regulator of the follicle’s ability to produce estradiol
Influence of Bovine Viral Diarrhea Virus Infection on Artificial Insemination Conception and Breeding Season Pregnancy Success in Vaccinated Beef Herds
Bovine Viral Diarrhea Virus (BVDV) causes reproductive economic losses in cattle. The objective of this study was to evaluate the influence of BVDV infection on reproductive success. Vaccinated cows (n = 370) and heifers (n = 528) from nine different herds were synchronized using the 7-day CO-Synch + CIDR protocol and were bred using fixed-time artificial insemination (FTAI). On d 28 following insemination, blood samples were collected and pregnancy status was determined. Non-pregnant animals were resynchronized and FTAI occurred a second time. In six herds, bulls were comingled with females beginning 10-15 d after the second AI. Final pregnancy status was determined 33-80 d following the first pregnancy diagnosis. Blood samples were tested for the presence of BVDV antigen using the IDEXX BVDV PI X2 Kit. Animals that tested positive were considered infected with BVDV at the time of blood collection. Herds were determined to be BVDV infected by the presence of at least one animal having a positive test for antigen (n = 4 infected herds, n = 5 non-infected herds). Statistical analyses were performed using the GLIMMIX procedure of SAS with herd as a random variable. Herds that had evidence of BVDV infection at d 28 following insemination had significantly decreased (P \u3c 0.01) first service AI conception rates compared to herds that had no evidence of infection (34 ± 2.3% vs. 54 ± 2.3%, respectively). Additionally, breeding season pregnancy rates were decreased (P \u3c 0.01) in BVDV infected herds compared to non-infected herds (69 ± 3.4% vs. 80 ± 3.6%, respectively). There was no significant effect of BVDV infection status on embryonic loss (P = 0.42) or percentage of animals which lost a pregnancy and rebred by the end of the breeding season (P = 0.63). In conclusion, BVDV infection in well vaccinated herds had a significant negative impact on both first service AI conception rate and overall breeding season pregnancy success
Hydrodynamic Hunters
The Gram-negative Bdellovibrio bacteriovorus (BV) is a model bacterial predator that hunts other bacteria and may serve as a living antibiotic. Despite over 50 years since its discovery, it is suggested that BV probably collides into its prey at random. It remains unclear to what degree, if any, BV uses chemical cues to target its prey. The targeted search problem by the predator for its prey in three dimensions is a difficult problem: it requires the predator to sensitively detect prey and forecast its mobile prey’s future position on the basis of previously detected signal. Here instead we find that rather than chemically detecting prey, hydrodynamics forces BV into regions high in prey density, thereby improving its odds of a chance collision with prey and ultimately reducing BV’s search space for prey. We do so by showing that BV’s dynamics are strongly influenced by self-generated hydrodynamic flow fields forcing BV onto surfaces and, for large enough defects on surfaces, forcing BV in orbital motion around these defects. Key experimental controls and calculations recapitulate the hydrodynamic origin of these behaviors. While BV’s prey (Escherichia coli) are too small to trap BV in hydrodynamic orbit, the prey are also susceptible to their own hydrodynamic fields, substantially confining them to surfaces and defects where mobile predator and prey density is now dramatically enhanced. Colocalization, driven by hydrodynamics, ultimately reduces BV’s search space for prey from three to two dimensions (on surfaces) even down to a single dimension (around defects). We conclude that BV’s search for individual prey remains random, as suggested in the literature, but confined, however—by generic hydrodynamic forces—to reduced dimensionality
BRAF mutation is not predictive of long-term outcome in papillary thyroid carcinoma
The BRAF mutation occurs commonly in papillary thyroid carcinoma (PTC). Previous investigations of its utility to predict recurrence-free survival (RFS) and disease-specific survival (DSS) have reported conflicting results and its role remains unclear. The purpose of this retrospective study was to determine the incidence of the BRAF mutation and analyze its relationship to clinicopathologic risk factors and long-term outcomes in the largest, single-institution American cohort to date. BRAF mutational status was determined in 508 PTC patients using RFLP analysis. The relationships between BRAF mutation status, patient and tumor characteristics, RFS, and DSS were analyzed. The BRAF mutation was present in 67% of patients. On multivariate analysis, presence of the mutation predicted only for capsular invasion (HR, 1.7; 95% CI, 1.1–2.6), cervical lymph node involvement (HR, 1.7; 95% CI, 1.1–2.7), and classic papillary histology (HR, 1.8; 95% CI 1.1–2.9). There was no significant relationship between the BRAF mutation and RFS or DSS, an observation that was consistent across univariate, multivariate, and Kaplan–Meier analyses. This is the most extensive study to date in the United States to demonstrate that BRAF mutation is of no predictive value for recurrence or survival in PTC. We found correlations of BRAF status and several clinicopathologic characteristics of high-risk disease, but limited evidence that the mutation correlates with more extensive or aggressive disease. This analysis suggests that BRAF is minimally prognostic in PTC. However, prevalence of the BRAF mutation is 70% in the general population, providing the opportunity for targeted therapy
Traumatic brain injury in individuals at clinical high risk for psychosis
Recent research suggests that a traumatic brain injury (TBI) can significantly increase the risk of later development of psychosis. However, it is unknown whether people at clinical high risk (CHR) of psychosis have experienced TBI at higher rates, compared to otherwise healthy individuals. This study evaluated the prevalence of mild TBI, whether it was related to past trauma and the relationship of mild TBI to later transition to psychosis
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