Plasmodium GPI-anchored micronemal antigen is essential for parasite transmission through the mosquito host

Plasmodium parasites, the eukaryotic pathogens that cause malaria, feature three distinct invasive forms tailored to the host environment they must navigate and invade for life cycle progression. One conserved feature of these invasive forms is the micronemes, apically oriented secretory organelles involved in egress, motility, adhesion, and invasion. Here we investigate the role of GPI-anchored micronemal antigen (GAMA), which shows a micronemal localization in all zoite forms of the rodent-infecting species Plasmodium berghei. ∆GAMA parasites are severely defective for invasion of the mosquito midgut. Once formed, oocysts develop normally, however, sporozoites are unable to egress and exhibit defective motility. Epitope-tagging of GAMA revealed tight temporal expression late during sporogony and showed that GAMA is shed during sporozoite gliding motility in a similar manner to circumsporozoite protein. Complementation of P. berghei knockout parasites with full-length P. falciparum GAMA partially restored infectivity to mosquitoes, indicating conservation of function across Plasmodium species. A suite of parasites with GAMA expressed under the promoters of CTRP, CAP380, and TRAP, further confirmed the involvement of GAMA in midgut infection, motility, and vertebrate infection. These data show GAMA's involvement in sporozoite motility, egress, and invasion, implicating GAMA as a regulator of microneme function.

Effect of valproic acid upon skeletal muscle subjected to prolonged tourniquet application

Background

Valproic acid (VPA), a histone deacetylase inhibitor, has shown improved outcomes when used as a pharmaceutical intervention in animal studies of hemorrhage, septic shock, and combined injuries. This study was designed to investigate the ability of VPA to mitigate ischemia-reperfusion injury produced by prolonged tourniquet application to an extremity.

Methods

The ischemia-reperfusion model in anesthetized rats was established using hemorrhage and a 3-hour tourniquet application. VPA was administered intravenously prior to tourniquet wear and removal. Ischemia-reperfusion injury was evaluated by investigating pathway signaling, immune modulation of cytokine release, remote organ injury, and skeletal muscle function during convalescence.

Results

We found that VPA sustained Protein kinase B (Akt) phosphorylation and Insulin-like growth factor signaling and modulated the systemic release of interleukin (IL)-1β, tumor necrosis factor alpha, and IL-6 after 2 hours of limb reperfusion. Additionally, VPA attenuated a loss in glomerular filtration rate at 3 days after injury. Histological and functional evaluation of extremity skeletal muscle at 3, 7, and 21 days after injury, however, demonstrated no significant differences in myocytic degeneration, necrotic formation, and maximal isometric tetanic torque.

Conclusions

Our results demonstrate that VPA sustains early prosurvival cell signaling, reduces the inflammatory response, and improves renal function in a hemorrhage with prolonged ischemia and reperfusion model. However, these do not translate into meaningful preservation in limb function when applied as a pharmaceutical augmentation to tourniquet wear.

Level of evidence

IV.

Molecular Damage in Aging

Cellular metabolism generates molecular damage affecting all levels of biological organization. Accumulation of this damage over time is thought to play a central role in the aging process, but damage manifests in diverse molecular forms complicating its assessment. Insufficient attention has been paid to date to the role of molecular damage in aging-related phenotypes, particularly in humans, in part because of the difficulty in measuring its various forms. Recently, omics approaches have been developed that begin to address this challenge, because they are able to assess a sizeable proportion of age-related damage at the level of small molecules, proteins, RNA, DNA, organelles and cells. This review describes the concept of molecular damage in aging and discusses its diverse aspects from theoretical models to experimental approaches. Measurement of multiple types of damage enables studies of the role of damage in human aging outcomes and lays a foundation for testing interventions to reduce the burden of molecular damage, opening new approaches to slowing aging and reducing its consequences.

Impact of recent artisanal small-scale gold mining in Senegal: Mercury and methylmercury contamination of terrestrial and aquatic ecosystems

In Senegal, the environmental impact of artisanal small-scale gold mining (ASGM) using mercury (Hg) is poorly documented despite its intensification over the past two decades. We report here a complete dataset including the distribution and speciation of Hg in soil, sediment, and water in pristine and ASGM impacted sites of the Gambia River ecosystem (Kedougou region - eastern Senegal). Selective extraction showed that soils surrounding ASGM activities were contaminated with elemental Hg [Hg(0)] at concentrations up to 3.9 mg kg^-1. In the Gambia River, high total Hg (THg: 1.16 ± 0.80 mg kg^-1) and methylmercury (MeHg: 3.2 ± 2.3 ng g^-1) were also measured in sediment samples collected at ASGM sites. Along the stream, THg concentrations in sediment decrease with distance from the ASGM sites, while those of methylmercury increase downstream. The study of THg and MeHg partitioning between filtered surface water and suspended particles demonstrate that particulate transport is responsible for the downstream dissemination of the Hg contamination from ASGM sites. Sedimentation of fine particles enriched in Hg downstream ASGM sites likely favors MeHg production and accumulation in sediment. Although elemental Hg is weakly labile, surface soil erosion may also provide important and long-term Hg inputs to downstream aquatic ecosystems, where it can be oxidized and methylated. Finally, the dissemination of THg and MeHg downstream from the ASGM sites in the Gambia River may constitute a long-term source of contamination and can have a large scale impact on the aquatic ecosystem through biomagnification.

Human exposure to mercury in artisanal small-scale gold mining areas of Kedougou region, Senegal, as a function of occupational activity and fish consumption

We investigated mercury (Hg) exposure of food web and humans in the region of Kedougou, Senegal, where Hg is used for gold amalgamation in artisanal small-scale gold mining (ASGM). For this purpose, total mercury (THg) concentration was determined in eight fish species and two shellfish species from Gambia River and in human hair from 111 volunteers of different age and sex, living in urban locations (Kedougou and Samekouta) or in ASGM areas (Tinkoto and Bantako). THg concentrations in fish samples range from 0.03 to 0.51 mg kg(-1) wet weight (ww) and 0.5 to 1.05 mg kg(-1) ww for shellfish. THg concentrations in fish are below the WHO guideline of 0.5 mg kg(-1) ww, whereas 100 % of shellfish are above this safety guideline. In the entire set of fish and shellfish samples, we documented a decrease of THg concentrations with increasing selenium to mercury (Se:Hg) ratio suggesting a protection of Se against Hg. However, local population consuming fish from the Gambia River in the two ASGM areas have higher THg concentrations (median = 1.45 and 1.5 mg kg(-1) at Bantako and Tinkoto) in hair than those from others localities (median = 0.42 and 0.32 mg kg(-1) at Kedougou town and Samekouta) who have diverse diets. At ASGM sites, about 30 % of the local population present Hg concentrations in hair exceeding 1 mg kg(-1), defined as the reference concentration of Hg in hair. We also evidence a higher exposure of women to Hg in the Tinkoto ASGM site due to the traditional distribution of daily tasks where women are more involved in the burning of amalgams. The discrepancy between the calculated moderate exposure through fish consumption and the high Hg concentrations measured in hair suggest that fish consumption is not the only source of Hg exposure and that further studies should focus on direct exposure to elemental Hg of population living at ASGM sites.

Targeted peptide measurements in biology and medicine: best practices for mass spectrometry-based assay development using a fit-for-purpose approach

Adoption of targeted mass spectrometry (MS) approaches such as multiple reaction monitoring (MRM) to study biological and biomedical questions is well underway in the proteomics community. Successful application depends on the ability to generate reliable assays that uniquely and confidently identify target peptides in a sample. Unfortunately, there is a wide range of criteria being applied to say that an assay has been successfully developed. There is no consensus on what criteria are acceptable and little understanding of the impact of variable criteria on the quality of the results generated. Publications describing targeted MS assays for peptides frequently do not contain sufficient information for readers to establish confidence that the tests work as intended or to be able to apply the tests described in their own labs. Guidance must be developed so that targeted MS assays with established performance can be made widely distributed and applied by many labs worldwide. To begin to address the problems and their solutions, a workshop was held at the National Institutes of Health with representatives from the multiple communities developing and employing targeted MS assays. Participants discussed the analytical goals of their experiments and the experimental evidence needed to establish that the assays they develop work as intended and are achieving the required levels of performance. Using this "fit-for-purpose" approach, the group defined three tiers of assays distinguished by their performance and extent of analytical characterization. Computational and statistical tools useful for the analysis of targeted MS results were described. Participants also detailed the information that authors need to provide in their manuscripts to enable reviewers and readers to clearly understand what procedures were performed and to evaluate the reliability of the peptide or protein quantification measurements reported. This paper presents a summary of the meeting and recommendations.

Dual energy CT myelography after lumbar osteosynthesis

PURPOSE

The purpose of this study was to evaluate the benefits of CT myelography in the DE technique in patients with lumbar osteosynthesis.

MATERIALS AND METHODS

In 30 patients a DE-CT scan of the spine with tube voltages of 80 kV and 140 kV was performed and a virtual monochromatic series of 120 kV was generated after intrathecal contrast injection. The impact of metal artifacts on the spinal canal and the spinal foramina was evaluated. The visualization of nerve roots was compared between a VRT series of the dural sac and conventional myelography.

RESULTS

With tube voltages of 140 kV, the artifacts were least pronounced. As no overlay disturbance was present, VRT visualization of the nerve roots was more reliable than conventional myelography.

CONCLUSION

In patients after osteosynthesis, CT in the DE technique provides minimal artifact disturbance using a tube voltage of 140 kV. "Virtual myelography" seems to be superior to conventional myelography for the evaluation of nerve roots. This could reduce additional conventional radiography, may shorten the entire examination and radiation time and diminish unnecessary painful movements for the patient.

Abstract P6-02-03: TGF-b1-inducible protein BIGH3 (transforming growth factor beta-induced gene human clone 3): A new mechanism inducing breast cancer cell apoptosis

Cancer development and progression is a complex process involving tumor cell mechanisms as well as tumor-host cell interactions. Using autocrine and paracrine mechanisms the cytokine TGF-b1 can influence cancer progression, in part through promoting the synthesis and secretion of extracellular matrix molecules. TGF-β1 strongly upregulates the gene TGFBI, which encodes a secretory protein named BIGH3. BIGH3 is an extracellular matrix, adhesion-class proapoptotic protein characterized by four fasciclin-1 (FAS1)-like domains, a cysteine-rich region and several different integrin-binding sequences. The C-terminus of BIGH3 encodes the integrin-binding peptides EPDIM and RGD. These sequences, and the integrin α3β1, have been implicated as important components of BIGH3-induced apoptosis. Breast cancer cells express the integrin α3β1, which is reported to play various roles including signaling, invasion and metastasis. Breast cancer cells and tumor-host cells express BIGH3 protein, which is expected to accumulate in the presence of TGF-β1. The above findings highlight the molecules TGF-β1 and α3β1 in tumor progression and are the basis for our hypothesis that BIGH3 protein itself is sufficient to induce an increase in breast cancer cell apoptosis. In order to test this hypothesis we utilized human breast cancer MCF-7 cells, human recombinant BIGH3 and TUNEL assays. Here, we show for the first time that exogenous human recombinant BIGH3 in cancer cell growth medium evokes a statistically significant increase in breast cancer cell apoptosis. A concentration curve shows that there is a direct relationship between the quantity of BIGH3 in the cells’ milieu and the number of cells undergoing apoptosis. This finding is consistent with receptor-ligand binding and indicates that BIGH3 is a potential target for breast cancer treatment. Importantly, in-house developed anti-BIGH3 antibody completely blocked apoptosis when compared to apoptotic cells in negative control conditions. Stimulation of BIGH3 gene expression in breast cancer cells, and providing exogenous BIGH3 to breast cancer cells, are expected to diminish breast cancer progression. Along this line, BIGH3 may be valuable as an agent for neoadjuvant or adjuvant therapy for human breast cancer patients.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-02-03.

New Concept: Different Types of Insufficiency of the Saphenofemoral Junction Identified by Duplex as a Chance for a More Differentiated Therapy of the Great Saphenous Vein

Even though the item ‘saphenofemoral junction’ (SFJ) is anatomically well defined, the incontinence of the SFJ is often incompetently described in clinical practice and studies. Especially with regard to the optimal therapy of the great saphenous vein, it might be of importance to have a more distinct regard to the SFJ as it is known that about 10–30% of the saphenous refluxes have no femoral origin. Considering the terminal and preterminal valve three types of incompetence of the SFJ may be differentiated: Type 1: Incompetent terminal, but competent preterminal valve; Type 2: Competent terminal, but incompetent preterminal valve; Type 3: Incompetent terminal and preterminal valve (complete incompetence). A review on prior studies and reports leads to the assumption that the differentiation of the distinct types of SFJ-incompetence allows a more individual and – perhaps – more effective therapy. Finally, studies are necessary to evaluate the here given new concept.

c-ANCA-induced neutrophil-mediated lung injury: a model of acute Wegener's granulomatosis

Anti-neutrophil cytoplasmic antibodies (c-ANCA) targeting proteinase 3 (PR3) are implicated in the pathogenesis of Wegener's granulomatosis (WG). Fulminant disease can present as acute lung injury (ALI). In this study, a model of ALI in WG was developed using isolated rat lungs. Isolated human polymorphonuclear leukocytes (PMNs) were primed with tumour necrosis factor (TNF) to induce surface expression of PR3. Co-perfusion of TNF-primed neutrophils and monoclonal anti-PR3 antibodies induced a massive weight gain in isolated lungs. This effect was not observed when control immunoglobulin G was co-perfused with TNF-primed PMNs. The c-ANCA-induced oedema formation was paralleled by an increase in the capillary filtration coefficient as a marker of increased pulmonary endothelial permeability. In contrast, pulmonary artery pressure was not affected. In the presence of the oxygen radical scavenger superoxide dismutase and a NADPH oxidase inhibitor, c-ANCA-induced lung oedema could be prevented. Inhibition of neutrophil elastase was equally effective in preventing c-ANCA-induced lung injury. In conclusion, anti-PR3 antibodies induced neutrophil mediated, elastase- and oxygen radical-dependent ALI in the isolated lung. This experimental model supports the hypothesis of a pathogenic role for c-ANCA in WG and offers the possibility of the development of therapeutic strategies for the treatment of lung injury in fulminant WG.

Lymph node metastases in soft tissue sarcomas: a single center analysis of 1,597 patients

PURPOSE

The aim of this study was to examine the clinical course of patients with the rare finding of regional lymph node metastasis (RLNM) from soft tissue sarcoma.

MATERIALS AND METHODS

Data from 28 out of 1,597 consecutive soft tissue sarcoma patients with RLNM were from the patients' charts and interviewing patients and general practitioners. Survival, including possible influencing factors, was statistically calculated.

RESULTS

RLNM was seen in 21.4% for epithelioid sarcoma and 17.6% for clear cell sarcoma. All other entities presented RLNM rates below 10%. At follow-up after an average of 9.6 years, only three patients were alive with no evidence of disease. Survival was independent from surgical resection status of the primary tumor and the RLNM as well as from adjuvant radiation and chemotherapy. Tumor entity as well as the length of the time period from primary to RLNM affect survival.

CONCLUSIONS

Surgical treatment as well as radiation and chemotherapy may improve survival in selected cases but probably have their value much more in terms of local disease control and improvement life quality of patients who probably already suffer from an aggressive systemic disease at time of nodal involvement.

Packing Capillary Columns for RP-HPLC

INTRODUCTIONCapillary or microcolumn (<0.5-mm internal diameter [I.D.]) high-performance liquid chromatography (HPLC) is an extremely powerful technique for separating small quantities of proteins and peptides. This protocol describes a procedure for adapting conventional HPLC systems to provide accurate low-flow rates (0.4-4 μl/min) and gradients required to operate slurry-packed capillary columns. A key component of this system is a commercial axial-beam longitudinal flow cell that can be fitted to a number of commercial UV detectors. Procedures are described for the fabrication of 0.32-mm I.D. polyimide-coated fused-silica columns, slurry-packed with reversed-phase chromatographic supports.

Biosynthesis of vascular endothelial growth factor-D involves proteolytic processing which generates non-covalent homodimers

Vascular endothelial growth factor-D (VEGF-D) binds and activates the endothelial cell tyrosine kinase receptors VEGF receptor-2 (VEGFR-2) and VEGF receptor-3 (VEGFR-3), is mitogenic for endothelial cells, and shares structural homology and receptor specificity with VEGF-C. The primary translation product of VEGF-D has long N- and C-terminal polypeptide extensions in addition to a central VEGF homology domain (VHD). The VHD of VEGF-D is sufficient to bind and activate VEGFR-2 and VEGFR-3. Here we report that VEGF-D is proteolytically processed to release the VHD. Studies in 293EBNA cells demonstrated that VEGF-D undergoes N- and C-terminal cleavage events to produce numerous secreted polypeptides including a fully processed form of M(r) approximately 21,000 consisting only of the VHD, which is predominantly a non-covalent dimer. Biosensor analysis demonstrated that the VHD has approximately 290- and approximately 40-fold greater affinity for VEGFR-2 and VEGFR-3, respectively, compared with unprocessed VEGF-D. In situ hybridization demonstrated that embryonic lung is a major site of expression of the VEGF-D gene. Processed forms of VEGF-D were detected in embryonic lung indicating that VEGF-D is proteolytically processed in vivo.

Low dose cabergoline induced interstitial pneumonitis

Certain dopaminergic anti-Parkinson drugs (ergolines) have repeatedly been identified as a cause of pleuropulmonary disease with a focus on serosal cell damage. Recently, a pathogenetic link between ergolines and prior asbestos exposure was suggested, as regards the development of pleural pathology. This report describes a patient with idiopathic Parkinson's disease, who was on a multiple drug regimen including low dose cabergoline. The patient developed a febrile illness with widespread bilateral lung infiltrations nonresponsive to beta-lactam and macrolide antibiotics. Bronchoalveolar lavage and transbronchial lung biopsy showed a "hypersensitivity-like" interstitial lung disease, which cleared almost completely within 2 months after simple drug withdrawal. Circumstantial evidence suggests a so far undescribed adverse lung reaction to cabergoline, devoid of the more usual pleural changes.

The role of intermolecular interactions: studies on model systems for bacterial biofilms

The mechanical stability of biofilms and other microbial aggregates is of great importance for both the maintenance of biofilm processes and the removal of undesired biofilms. The binding forces are weak interactions such as London dispersion forces, electrostatic interactions and hydrogen bonds. In a first attempt to rank their contribution, the viscosity of solutions of extracellular polymeric substances (EPS) from a mucoid strain of Pseudomonas aeruginosa is measured. In order to distinguish the binding forces, substances are chosen which individually address the different types of bonds. Polyacrylic acid is identified as a suitable model system for EPS when molecular interactions are studied. Electrostatic interactions and hydrogen bonds are found to be the dominating forces among macromolecules within the biofilm.

You can be prepared when JCAHO visits

Preparations for Joint Commission on Accreditation of Healthcare Organizations (JCAHO) surveys are rarely described in the literature. This article is intended to provide much-needed information on survey preparation processes, not only to Department of Veterans Affairs medical centers, but also to all hospitals undergoing surveys of biopsychosocial delivery of care. Beginning in 1995, JCAHO will apply biopsychosocial reviews to all assessments of patients. Facilities whose preparations include those detailed in this article will be better prepared for such reviews.

[Caries protective effect of a NaF containing toothpaste with and without calcium carbonate polishing agent]

A caries preventive effect depending on the free fluoride concentration was registrated on rats using dentifrices with NaF or MFP (alone or in combination) despite the presence of CaCO3 as abrasive material because the composition of these dentifrices was changed. The free fluoride concentration of dentifrices had induced the accumulation of fluoride into enamel. The ionized fluoride content of NaF-dentifrices was unchanged for 3 years. MFP was hydrolized and had continuously released fluoride ions. The caries preventive effect which was increased by HCO3- was reproducible in correspondence with the fluoride concentration after the storage for two years.

[The use of nitrous oxide as a contrast medium during fractionated gas encephalography in halane-nitrous-oxide anesthesia]

40 children were employed as test cases in fractionated gas encephalography using Halan-nitrous oxide anesthesia, and the level of cerebrospinal pressure, the röntgenoparent quality of the extracerebral spaces and the duration of postencephalographical symptoms were examined using air and nitrous oxide as contrast media. In the course of the examination the cerebrospinal pressure showed a tendency to rise when air was introduced, to fall when nitrous oxide was introduced. After instillation of N2O however the filling of the subarachnoid space was over so quickly that it could not be included in the assessment. Sufficient röntgenograms were obtained for all diagnostic demands through 'hybrid filling', (introduction of nitrous oxide into the ventricles, introduction of air into the subarachnoid spaces). With the aid of the results obtained from this examination attempts will be made to derive differentiated indications for filling with nitrous oxide.