Mangrove Sedimentation and Response to Relative Sea-Level Rise

Mangroves occur on upper intertidal shorelines in the tropics and subtropics. Complex hydrodynamic and salinity conditions, related primarily to elevation and hydroperiod, influence mangrove distributions; this review considers how these distributions change over time. Accumulation rates of allochthonous and autochthonous sediment, both inorganic and organic, vary between and within different settings. Abundant terrigenous sediment can form dynamic mudbanks, and tides redistribute sediment, contrasting with mangrove peat in sediment-starved carbonate settings. Sediments underlying mangroves sequester carbon but also contain paleoenvironmental records of adjustments to past sea-level changes. Radiometric dating indicates long-term sedimentation, whereas measurements made using surface elevation tables and marker horizons provide shorter perspectives, indicating shallow subsurface processes of root growth and substrate autocompaction. Many tropical deltas also experience deep subsidence, which augments relative sea-level rise. The persistence of mangroves implies an ability to cope with moderately high rates of relative sea-level rise. However, many human pressures threaten mangroves, resulting in a continuing decline in their extent throughout the tropics.

Rat Cytomegalovirus Vaccine Prevents Accelerated Chronic Rejection in CMV-Naïve Recipients of Infected Donor Allograft Hearts

Cytomegalovirus accelerates transplant vascular sclerosis (TVS) and chronic rejection (CR) in solid organ transplants; however, the mechanisms involved are unclear. We determined the efficacy of a CMV vaccine in preventing CMV-accelerated rat cardiac allograft rejection in naïve recipients of CMV+ donor hearts. F344 donor rats were infected with RCMV 5 days prior to heterotopic cardiac transplantation into CMV-naïve or H2 O2 -inactivated RCMV-vaccinated Lewis recipients. Recipients of RCMV-infected donor hearts rejected at POD59, whereas vaccinated recipients exhibited a significantly prolonged time to rejection-POD97, similar to recipients of uninfected donor hearts (POD108). Although all of the donor hearts were preinfected, the vaccinated recipients had lower graft and PBMC viral loads at POD 7 compared to unvaccinated controls. Adoptive T cell and passive antibody transfers from vaccinated Lewis rats into naïve recipients demonstrate that both T-cell and B-cell arms of the adaptive immune response provide protection against CMV-accelerated rejection. Similar findings were obtained when testing three different adjuvants in passive transfer experiments. We have determined that the timing of the vaccine prior to transplantation and the specific adjuvant play critical roles in mediating anti-viral responses and promoting graft survival. CMV vaccination prior to transplantation may effectively increase graft survival.

Impact of telemedicine on the quality of forensic sexual abuse examinations in rural communities

To assess the quality and diagnostic accuracy of pediatric sexual abuse forensic examinations conducted at rural hospitals with access to telemedicine compared with examinations conducted at similar hospitals without telemedicine support. Medical records of children less than 18 years of age referred for sexual abuse forensic examinations were reviewed at five rural hospitals with access to telemedicine consultations and three comparison hospitals with existing sexual abuse programs without telemedicine. Forensic examination quality and accuracy were independently evaluated by expert review of state mandated forensic reporting forms, photo/video documentation, and medical records using two structured implicit review instruments. Among the 183 patients included in the study, 101 (55.2%) children were evaluated at telemedicine hospitals and 82 (44.8%) were evaluated at comparison hospitals. Evaluation of state mandatory sexual abuse examination reporting forms demonstrated that hospitals with telemedicine had significantly higher quality scores in several domains including the general exam, the genital exam, documentation of examination findings, the overall assessment, and the summed total quality score (p<0.05 for each). Evaluation of the photos/videos and medical records documenting the completeness and accuracy of the examinations demonstrated that hospitals with telemedicine also had significantly higher scores in several domains including photo/video quality, completeness of the examination, and the summed total completeness and accuracy score (p<0.05 for each). Rural hospitals using telemedicine for pediatric sexual abuse forensic examination consultations provided significantly higher quality evaluations, more complete examinations, and more accurate diagnoses than similar hospitals conducting examinations without telemedicine support.

Intra-crystalline protein diagenesis (IcPD) in Patella vulgata. Part I: Isolation and testing of the closed system

This study successfully isolates a fraction of intra-crystalline proteins from shells of the marine gastropod Patella vulgata and assesses the suitability of these proteins for IcPD (Intra-crystalline Protein Diagenesis) geochronology. We discuss the mineralogical composition of this gastropod, investigated for the first time by X-ray diffraction mapping, and use the results to inform our sampling strategy. The potential of the calcitic rim and of a bulk sample (containing both apex and rim) of the shell to act as stable repositories for the intra-crystalline proteins during diagenesis is examined. The composition and the diagenetic behaviour of the intra-crystalline proteins isolated from different locations within the shell are compared, highlighting the necessity of targeting consistent sampling positions. We induced artificial diagenesis of both intra-crystalline and whole-shell proteins by conducting high-temperature experiments in hydrous environment; this allowed us to quantify the loss of amino acids by leaching and therefore evaluate the open- or closed-system behaviour of the different fractions of proteins. The results obtained provide further confirmation that patterns of diagenesis vary according to the protein sequence, structure, and location within or outside the intra-crystalline fraction. As Patella is frequently found in the fossil record, both in archaeological and geological contexts, the application of IcPD geochronology to this biomineral opens up the possibility to obtain reliable age information from a range of sites in different areas of the world.

microRNA biogenesis and turnover in plants

microRNAs (miRNAs) are short RNAs that regulate gene expression in eukaryotes. The biogenesis and turnover of miRNAs determine their spatiotemporal accumulation within tissues. miRNA biogenesis is a multistep process that entails transcription, processing, nuclear export, and formation of the miRNA-ARGONAUTE complex. Factors that perform each of these steps have been identified. Generation of mature miRNAs from primary transcripts, i.e., miRNA processing, is a key step in miRNA biogenesis. Our understanding of miRNA processing has expanded beyond the enzyme that performs the reactions, as more and more additional factors that impact the efficiency and accuracy of miRNA processing are uncovered. In contrast to miRNA biogenesis, miRNA turnover is an important but poorly understood process that contributes to the steady-state levels of miRNAs. Enzymes responsible for miRNA degradation have only recently been identified. This review describes the processes of miRNA maturation and degradation in plants.

Abstract P3-06-28: Use of the MiCK drug-induced apoptosis assay improves clinical outcomes in recurrent breast cancer (BRCA)

Background: The microculture kinetic (MiCK) assay (Correct Chemo™) correlates with outcomes in acute myelocytic leukemia and ovarian cancer (Cancer Research, in press). A prior trial suggested that its use in breast cancer could improve clinical outcomes (Cancer, in press). This study was designed to correlate MiCK assay results with clinical outcomes in recurrent or metastatic BRCA.

Methods: 30 patients with recurrent or metastatic breast cancer in 4 different institutions were evaluated. Each patient (pt) had a BRCA biopsy sent to a central laboratory, tumor cells were purified to over 90% homogeneity, and were then cultured with individual drugs or drug combinations. The induction of apoptosis was measured every five minutes continuously for 48 hours. The amount of apoptosis was expressed in kinetic units (KU), and results were sent to the attending oncologist within 72 hours of submission. Physicians were free to choose any treatment plan for the pts, and were free to add hormonal therapy or biotherapy. Clinical results were evaluated by oncologists using clinical criteria and the results of the MiCK assay were correlated with outcomes of complete (CR) or partial (PR) response, time-to-relapse (TTR), and overall survival (OS).

Results: Median age was 57 years, and number of lines of prior therapy was a median of 2 (range 1–8). Median ECOG performance status was 1. The total number of drugs tested in the assay was a median of 12 (range 3–31). The MiCK assay was used to help select therapy in 22 pts (73%). There was change between drugs originally planned before MiCK assay and drugs used after MiCK in 15 pts (50%). The best therapy from the MiCK assay was used for treatment in 16 pts (53%). In five pts (17%), a single drug was used in place of a combination. Generic drugs were used in place of proprietary drugs in nine pts (30%). Hormonal therapy was added to drugs selected based on the MiCK assay in seven pts (23%), and bio-therapy drugs were added to chemotherapy drugs in eight pts (27%). If the MiCK results were used to help select therapy, eight pts had a CR or PR (27%), compared to 0 pts with CR or PR if MiCK was not used (p = 0.04). If the MiCK assay was used to determine therapy, 17 pts (59%) had a CR, PR or stable disease compared to only 2 pts (6.9%) in whom the MiCK assay was not used (p &lt; 0.01). The TTR was significantly longer if the MiCK assay was used to select chemotherapy, 7.4 months, compared to only 2.2 months if the MiCK assay was not used (p &lt; 0.01). There was a trend toward longer survival if the MiCK assay was used, 16.8 months, compared to 13.1 months if the MiCK assay was not used, but the difference was not statistically significant (p = 0.3). If the best chemotherapy from the MiCK assay was used, there were trends for increased TTR (7.3 vs 3.9 mo if best not used p = 0.13) and increased rate of CR or PR or stable (54% vs 17% p = 0.11).

Conclusions: Use of the MiCK assay to determine chemotherapy was associated with a higher response rate and a longer time to relapse in pts with recurrent or metastatic BRCA. It is possible that OS is also improved, but longer follow up is needed. There was a trend for improved outcomes if the best chemotherapy based on the MiCK assay was used.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-06-28.

Bone mineral crystallisation kinetics

The kinetics of bone apatite crystallisation are examined using a novel approach to obtain quantitative, direction dependence features such as growth rate and activation energy. X-ray diffraction was employed for analysis of bovine, porcine and 'anorganic' bone specimens. Apatite coherence length was utilised as the independent variable within a Johnson-Mehl-Avrami (JMA) model. A direction averaged crystallisation activation energy of 183 ± 8 kJ mol(-1) was observed for the three bone groups. The Johnson-Mehl-Avrami 'n' exponent decreased with increasing temperature for all bone groups, indicating that apatite crystallisation changes to a diffusion limited process at higher temperatures. The results revealed little evidence to support any organic component 'protective' effect, and, on the contrary indicated that the organic matrix promotes apatite crystallisation.

Monaural conductive hearing loss alters the expression of the GluA3 AMPA and glycine receptor α1 subunits in bushy and fusiform cells of the cochlear nucleus

The impact of conductive hearing loss (CHL), the second most common form of hearing loss, on neuronal plasticity in the central auditory pathway is unknown. After short-term (1 day) monaural earplugging, the GluA3 subunits of the AMPA receptor (AMPAR) are upregulated at auditory nerve synapses on the projection neurons of the cochlear nucleus; glycine receptor α1 (GlyRα1) subunits are downregulated at inhibitory synapses in the same neuronal population. These data suggest that CHL affects receptor trafficking at synapses. We examined the impact of 7 days of CHL on the general expression of excitatory and inhibitory receptors by quantitative biochemistry and immunohistochemistry, using specific antibodies to detect AMPAR subunits (GluA1, GluA2, GluA2/3, and GluA4), GlyRα1, and the GABA(A) receptor subunits β2/3. Following monaural earplugging and an elevation of the hearing threshold by approximately 35 dB, the immunolabeling of the antibody for the GluA2/3 subunits but not the GluA2 subunit increased on bushy cells (BCs) and fusiform cells (FCs) of the ipsilateral ventral and dorsal cochlear nuclei. These same cell types showed a downregulation of the GlyRα1 subunit. Similar results were observed in the contralateral nuclei. The expression levels of GABA(A) β2/3 were unchanged. These findings suggest that, following longer periods of monaural conductive hearing loss, the synthesis and subsequent composition of specific glutamate and glycine receptors in projection neurons and their synapses are altered; these changes may contribute to abnormal auditory processing.

Effects of the interactions of classical swine fever virus Core protein with proteins of the SUMOylation pathway on virulence in swine

Here we have identified host cell proteins involved with the cellular SUMOylation pathway, SUMO-1 (small ubiquitin-like modifier) and UBC9, a SUMO-1 conjugating enzyme that interact with classical swine fever virus (CSFV) Core protein. Five highly conserved lysine residues (K179, K180, K220, K221, and K246) within the CSFV Core were identified as putative SUMOylation sites. Analysis of these interactions showed that K179A, K180A, and K221A substitutions disrupt Core-SUMO-1 binding, while K220A substitution precludes Core-UBC9 binding. In vivo, Core mutant viruses (K179A, K180A, K220A, K221A) and (K220A, K221A) harboring those substitutions were attenuated in swine. These data shows a clear correlation between the disruption of Core protein binding to SUMO-1 and UBC9 and CSFV attenuation. Overall, these data suggest that the interaction of Core with the cellular SUMOylation pathway plays a significant role in the CSFV growth cycle in vivo.

Associations between exercise-induced pulmonary haemorrhage, right ventricular dimensions and atrioventricular valve regurgitation in conditioned National Hunt racehorses

REASONS FOR PERFORMING STUDY

Exercise-induced pulmonary haemorrhage (EIPH) and tricuspid (TR) and mitral valve regurgitation (MR) are conditions with high prevalence in conditioned Thoroughbreds. Stress failure of pulmonary capillaries, leading to EIPH, is most likely when pulmonary vascular pressure is increased, and mitral regurgitation can result in pulmonary venous hypertension.

HYPOTHESIS

There might be an association between MR and EIPH and the right ventricle (RV) of horses known to suffer repeated episodes of EIPH, as their hearts would be subject to higher pulmonary vascular pressures and cardiac output during training and hence increased RV afterload and preload.

METHODS

An echocardiographic and auscultation study was conducted in 121 race-fit National Hunt Thoroughbreds. Cardiac auscultation and echocardiography were performed. A guided M-mode image of the RV just below the tricuspid valve was obtained from a right parasternal location and colour flow Doppler (CFD) used to interrogate the tricuspid valve and right atrium. The mitral valve was similarly examined from the left hemithorax. Severity of TR and MR by CFD was graded. Binary data on EIPH, based on whether the horse was perceived to have a clinically significant problem with EIPH, were determined retrospectively for each horse by the horses' primary care veterinary surgeon from medical and other records. Data were analysed using a standard logistic regression analysis approach.

RESULTS

EIPH was significantly and positively associated with the systolic and diastolic dimensions of the RV (P = 0.017 and 0.011 respectively) and this association was not sensitive to the effects of age or weight. There were no significant associations between EIPH and TR or MR by auscultation or CFD (TR: auscultation P = 0.1; CFD P = 0.2 and MR: auscultation P = 0.07; CFD P = 0.37).

CONCLUSIONS AND CLINICAL RELEVANCE

This study was limited by the method used to classify EIPH, but there was no association between EIPH and horse age, weight, TR or MR in this population of Thoroughbreds. Nevertheless, RV internal dimension was greater in horses obviously affected by EIPH, suggesting that factors resulting in EIPH may directly or indirectly affect RV remodelling in athletic horses.

Measurements of right ventricular internal dimensions and their relationships to severity of tricuspid valve regurgitation in National Hunt Thoroughbreds

REASONS FOR PERFORMING STUDY

The effect of tricuspid valve regurgitation (TR) in right ventricular (RV) chamber size has not been reported.

METHODS

An echocardiographic and auscultation study was conducted on 394 race-fit National Hunt Thoroughbreds (TBs) in 4 training yards. Auscultation was performed on each horse and audible murmurs of TR graded using a 1-6 scale. Echocardiography was also performed and standard, 2-dimensional (2D), short (SA) and long axis (LA) images of the RV obtained from a right parasternal location. An m-mode image was recorded from an SA view of the RV just below the level of the tricuspid valve. Colour flow Doppler (CFD) echocardiography was used to interrogate the tricuspid valve and right atrium. If retrograde flow was visible, representative recordings were also acquired. Severity of TR by CFD was graded using a subjective 1-9 scale. Measurements of RV chamber size in systole and diastole were made from archived 2D, LA, SA and m-mode images by a single observer unaware of the auscultation and CFD findings. To determine day-to-day repeatability of RV measurements from each imaging plane and of TR by CFD, 5 horses were examined on 5 consecutive days using an identical echocardiographic protocol. Images from 30 horses in the original dataset were also measured on a second occasion to determine the intra-observer repeatability.

RESULTS

There were significant positive correlations between the severity of TR by CFD and RV internal diameter from each image plane. In contrast, there were no significant associations between grade of TR by auscultation and any RV dimension. Data also showed that only RV measurements derived from M-mode images have acceptable intraobserver repeatability and similarly the M-mode measurements had the best overall day-to-day repeatability.

CONCLUSIONS AND CLINICAL RELEVANCE

Data showed that TR assessed by CFD was positively associated with the diastolic and systolic dimensions of the RV, but failed to demonstrate a positive association between the presence of a murmur of TR and RV chamber size. M-mode and 2D echocardiography provided moderately reliable and repeatable methods for obtaining measurements of RV internal dimensions. M-mode images provide the most reliable and repeatable measurements, particularly for less experienced operators.