ABSTRACT
Hazardous reactive dyes can cause serious environmental problems, as they are difficult to remove from water using conventional adsorbents due to their large molecular sizes and bulky structures. Sustainable mesoporous carbons derived from alginic acid demonstrated promising adsorbent capacity for several representative industrial bulky reactive dye molecules that account for almost 30% of the global textile dye market: Procion Yellow H-XEL (PY), Remazol Black (RB), Procion Crimson H-XEL (PC) and Procion Navy H-XEL (PN). These new adsorbents showed high mesoporosity (>90%) and large pore diameters (>20 nm) facilitating more straightforward and efficient adsorption and desorption processes when compared with predominately microporous activated carbon (AC), Norit, of similar surface chemistry, or with Silica gel (Sgel) that shows good mesoporosity but is hydrophilic. Their adsorption capacity was also significantly higher than that of both AC and Sgel, verifying suitability for bulky dye elimination from wastewater. Adsorption kinetic studies showed a best fit with the Elovich model, indicating a heterogeneous surface adsorption process. The adsorption isotherm data was best represented via the Toth model for almost all adsorbent/dye systems (R2 ≥ 0.98), validating the results of the Elovich model whereby the adsorbent is structurally heterogenous with multilayer dye coverage. From thermodynamic analysis, the derived parameters of ΔG (-11.6 â¼ -6.2 kJ/mol), ΔH and ΔS demonstrate a spontaneous, enthalpy controlled adsorption process that was exothermic for RB (-10.0 kJ/mol) and PC (-23.9 kJ/mol) and endothermic for PY (3.9 kJ/mol) and PN (13.2 kJ/mol). Overall these alginic acid based mesoporous carbons are cost-effective, sustainable and efficient alternatives to current predominantly microporous adsorbent systems.
Subject(s)
Coloring Agents , Water Pollutants, Chemical , Coloring Agents/chemistry , Water/chemistry , Adsorption , Kinetics , Alginic Acid , Thermodynamics , Water Pollutants, Chemical/chemistry , Hydrogen-Ion ConcentrationABSTRACT
Ground robotic vehicles are often deployed to inspect areas where radioactive floor contamination is a prominent risk. However, the accuracy of detection could be adversely affected by enhanced radiation signal through self-contamination of the robot occurring over the course of the inspection. In this work, it was hypothesised that a six-legged robot could offer advantages over the more conventional ground robotic devices such as wheeled and tracked rovers. To investigate this, experimental contamination testing and computational Monte Carlo simulation techniques (GEANT4) were employed to understand how radioactive contamination pick-up on three different robotic vehicles would affect their detection accuracy. Two robotic vehicles were selected for comparison with the hexapod robot based on their type of locomotion; a wheeled rover and a tracked rover. With the aid of a non-toxic fluorescent tracer dust, the contamination received by the all three vehicles when traversing a contaminated area was initially compared through physical inspection using high definition cameras. The parametric results from these tests where used in the computational study carried out in GEANT4. A cadmium zinc telluride detector was simulated at heights ranging from 10 to 50 cm above each contaminated vehicle, as if it were mounted on a plinth. Assuming a uniform activity of 60 Bq cm-2on all contaminated surfaces, the results suggested that due to the hexapod's small ground-contacting surface area and geometry, radiation detection rates using an uncollimated detector are likely to be overestimated by between only 0.07%-0.12%, compared with 3.95%-8.43% and 1.75%-14.53% for the wheeled and tracked robot alternatives, respectively.
Subject(s)
Robotic Surgical Procedures , Robotics , Computer Simulation , Monte Carlo MethodABSTRACT
BACKGROUND AND PURPOSE: T2 signal and FLAIR changes in patients undergoing stereotactic radiosurgery for brain AVMs may occur posttreatment and could result in adverse radiation effects. We aimed to evaluate outcomes in patients with these imaging changes, the frequency and degree of this response, and factors associated with it. MATERIALS AND METHODS: Through this retrospective cohort study, consecutive patients treated with stereotactic radiosurgery for brain AVMs who had at least 1 year of follow-up MR imaging were identified. Logistic regression analysis was used to evaluate predictors of outcomes. RESULTS: One-hundred-sixty AVMs were treated in 148 patients (mean, 35.6 years of age), including 42 (26.2%) pediatric AVMs. The mean MR imaging follow-up was 56.5 months. The median Spetzler-Martin grade was III. The mean maximal AVM diameter was 2.8 cm, and the mean AVM target volume was 7.4 mL. The median radiation dose was 16.5 Gy. New T2 signal and FLAIR hyperintensity were noted in 40% of AVMs. T2 FLAIR volumes at 3, 6, 12, 18, and 24 months were, respectively, 4.04, 55.47, 56.42, 48.06, and 29.38 mL Radiation-induced neurologic symptoms were encountered in 34.4%. In patients with radiation-induced imaging changes, 69.2% had new neurologic symptoms versus 9.5% of patients with no imaging changes (P = .0001). Imaging changes were significantly associated with new neurologic findings (P < .001). Larger AVM maximal diameter (P = .04) and the presence of multiple feeding arteries (P = .01) were associated with radiation-induced imaging changes. CONCLUSIONS: Radiation-induced imaging changes are common following linear particle accelerator-based stereotactic radiosurgery for brain AVMs, appear to peak at 12 months, and are significantly associated with new neurologic findings.
Subject(s)
Brain Edema/etiology , Intracranial Arteriovenous Malformations/radiotherapy , Radiation Injuries/diagnostic imaging , Radiation Injuries/pathology , Radiosurgery/adverse effects , Adolescent , Adult , Aged , Brain Edema/diagnostic imaging , Child , Child, Preschool , Cohort Studies , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Radiosurgery/methods , Retrospective Studies , Treatment OutcomeABSTRACT
Microsporidia are obligate intracellular, spore-forming, fungal-related pathogens that employ a unique organelle, the polar tube, to transfer infectious spore contents into host cells to initiate infection. Spore adherence to host cells may provide the proximity required for polar tube/host cell interaction during in vivo infection. In previous in vitro studies, host sulfated glycosaminoglycans (GAGs) or recombinant microsporidia endospore protein (EnP1) was implicated in the pathogen adherence and infection process; however, complete ablation of spore adherence and infection could not be achieved, suggesting that additional or alternative spore and host cell determinants of adherence and infection may exist. Analysis of the Encephalitozoon intestinalis genome revealed about 100 predicted proteins containing the canonical integrin-binding motif arginine-glycine-aspartic acid (RGD); and, many pathogens have been shown to engage integrin molecules on cell surfaces. We hypothesized that host cell integrins play a role in microsporidia adherence and infection. In this study, we demonstrated that addition of exogenous integrin ligands or recombinant alpha 3 beta 1 integrin or alpha 5 beta 1 integrin to assays of E. intestinalis adherence and infection significantly reduced spore adherence and infection of host cells, supporting our hypothesis and implicating these specific integrins as putative host cell receptors for E. intestinalis spores.
Subject(s)
Carrier Proteins/metabolism , Encephalitozoon/genetics , Encephalitozoon/physiology , Host-Pathogen Interactions , Integrins/metabolism , Animals , Carrier Proteins/chemistry , Carrier Proteins/genetics , Cell Membrane/metabolism , Chlorocebus aethiops , Encephalitozoon/pathogenicity , Fungal Proteins/genetics , Fungal Proteins/metabolism , Genome, Fungal , Ligands , Receptors, Cell Surface/metabolism , Spores, Fungal/physiology , Vero CellsSubject(s)
Bacterial Infections/diagnosis , Breath Tests/methods , Duodenum/microbiology , Female , Humans , MaleABSTRACT
Multidrug-resistant bacteria cause severe infections in hospitals and communities. Development of new drugs to combat resistant microorganisms is needed. Natural products of microbial origin are the source of most currently available antibiotics. We hypothesized that random mutagenesis of Aspergillus oryzae would result in secretion of antibacterial compounds. To address this hypothesis, we developed a screen to identify individual A. oryzae mutants that inhibit the growth of Methicillin-resistant Staphylococcus aureus (MRSA) in vitro. To randomly generate A. oryzae mutant strains, spores were treated with ethyl methanesulfonate (EMS). Over 3000 EMS-treated A. oryzae cultures were tested in the screen, and one isolate, CAL220, exhibited altered morphology and antibacterial activity. Culture supernatant from this isolate showed antibacterial activity against Methicillin-sensitive Staphylococcus aureus, MRSA, and Pseudomonas aeruginosa, but not Klebsiella pneumonia or Proteus vulgaris. The results of this study support our hypothesis and suggest that the screen used is sufficient and appropriate to detect secreted antibacterial fungal compounds resulting from mutagenesis of A. oryzae. Because the genome of A. oryzae has been sequenced and systems are available for genetic transformation of this organism, targeted as well as random mutations may be introduced to facilitate the discovery of novel antibacterial compounds using this system.
ABSTRACT
PURPOSE: To assess the effectiveness of the management of patients with cardiac electronic implantable devices (CEIDS) receiving radiotherapy. METHOD AND MATERIALS: In 2005, a formal communication process was established between Radiation Oncology and Cardiac Electrophysiology (EP) for the management of patients with permanent, implantable cardiac devices receiving radiotherapy. The process requires a pre-treatment consult with EP. This information is provided to a medical physicist, who works with the primary radiation oncologist and dosimetrist. Based on the estimated dose to the device, EP and Radiation Oncology will determine the appropriate oversight required for treatment. To assess the effectiveness of this program, a retrospective analysis of patients with implantable cardiac devices receiving radiotherapy between the years 2005 and 2011 was performed. RESULTS: Sixty-nine patients with CEIDs (19 implantable cardioverter defibrillators (ICDs) and 50 pacemakers) were treated in Radiation Oncology between 2005 and 2011. Patients were treated to a variety of sites, including 21 patients treated to multiple sites. Doses were estimated prior to radiotherapy, and in vivo measurements were obtained for patients near or exceeding our institutional device tolerance (ICDs = 1 Gy and ICPs = 2 Gy), or if the device was less than 10 cm from the edge of a treatment field. Of the patients evaluated, there were only two patients with ICD devices which had a partial reset of diagnostic data during their treatment. There were no major device failures of arrhythmia detection or treatment. CONCLUSIONS: Our multi-disciplinary team has worked together to develop a process to manage the care of patients with permanent implantable cardiac devices. There have been few device events noted in our patient cohort. The team will continue to follow our institutional management methodology to assess the appropriate amount of EP care necessary during radiation therapy. Laura Horwood is on the speakers bureau for Medtronic. Frank Pelosi is on the advisory board for Boston Scientific Corp and St. Jude Medical, is receiving an educational grants from Medtronic, St Jude, Boston Scientific, Biotronik, and a research grants from Medtronic.
ABSTRACT
Microsporidia spore surface proteins are an important, under investigated aspect of spore/host cell attachment and infection. For comparison analysis of surface proteins, we required an antibody control specific for an intracellular protein. An endoplasmic reticulum-associated heat shock protein 70 family member (Hsp70; ECU02_0100; "C1") was chosen for further analysis. DNA encoding the C1 hsp70 was amplified, cloned and used to heterologously express the C1 Hsp70 protein, and specific antiserum was generated. Two-dimensional Western blotting analysis showed that the purified antibodies were monospecific. Immunoelectron microscopy of developing and mature E. cuniculi spores revealed that the protein localized to internal structures and not to the spore surface. In spore adherence inhibition assays, the anti-C1 antibodies did not inhibit spore adherence to host cell surfaces, whereas antibodies to a known surface adhesin (EnP1) did so. In future studies, the antibodies to the 'C1' Hsp70 will be used to delineate spore surface protein expression.
Subject(s)
Bone Neoplasms/radiotherapy , Neoplasm Metastasis/radiotherapy , Bone Neoplasms/complications , Bone Neoplasms/economics , Bone Neoplasms/secondary , Dose Fractionation, Radiation , Dose-Response Relationship, Radiation , Humans , Pain/etiology , Pain/radiotherapy , Palliative Care/economics , Palliative Care/methods , United StatesABSTRACT
Microsporidia are spore-forming fungal pathogens that require the intracellular environment of host cells for propagation. We have shown that spores of the genus Encephalitozoon adhere to host cell surface glycosaminoglycans (GAGs) in vitro and that this adherence serves to modulate the infection process. In this study, a spore wall protein (EnP1; Encephalitozoon cuniculi ECU01_0820) from E. cuniculi and Encephalitozoon intestinalis is found to interact with the host cell surface. Analysis of the amino acid sequence reveals multiple heparin-binding motifs, which are known to interact with extracellular matrices. Both recombinant EnP1 protein and purified EnP1 antibody inhibit spore adherence, resulting in decreased host cell infection. Furthermore, when the N-terminal heparin-binding motif is deleted by site-directed mutagenesis, inhibition of adherence is ablated. Our transmission immunoelectron microscopy reveals that EnP1 is embedded in the microsporidial endospore and exospore and is found in high abundance in the polar sac/anchoring disk region, an area from which the everting polar tube is released. Finally, by using a host cell binding assay, EnP1 is shown to bind host cell surfaces but not to those that lack surface GAGs. Collectively, these data show that given its expression in both the endospore and the exospore, EnP1 is a microsporidian cell wall protein that may function both in a structural capacity and in modulating in vitro host cell adherence and infection.
Subject(s)
Cell Wall/chemistry , Encephalitozoon/chemistry , Fungal Proteins/chemistry , Spores, Fungal/chemistry , Amino Acid Sequence , Animals , Blotting, Western , CHO Cells/parasitology , Cells, Cultured , Chlorocebus aethiops , Cricetinae , Cricetulus , Fungal Proteins/genetics , Host-Parasite Interactions/physiology , Molecular Sequence Data , Rabbits , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Sequence Alignment , Spores, Fungal/physiology , Vero Cells/parasitologySubject(s)
Fungal Proteins/physiology , Microsporidia/physiology , Animals , Cell Adhesion/genetics , Cell Adhesion/physiology , Cell Line , Chlorocebus aethiops , Fungal Proteins/genetics , Microsporidia/genetics , Rabbits , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Spores, Fungal/geneticsABSTRACT
The objective of this study was to determine the feasibility and acceptability of a referral and outcall programme from a telephone-based information and support service, for men newly diagnosed with colorectal or prostate cancer. A block randomized controlled trial was performed involving 100 newly diagnosed colorectal and prostate cancer patients. Patients were referred to the Cancer Information Support Service (CISS) through clinicians at diagnosis. Clinicians were randomized into one of three conditions. Active referral 1: specialist referral with four CISS outcalls: (1)Subject(s)
Colorectal Neoplasms/therapy
, Prostatic Neoplasms/therapy
, Referral and Consultation/organization & administration
, Telemedicine/methods
, Telephone
, Adult
, Aged
, Aged, 80 and over
, Colorectal Neoplasms/psychology
, Feasibility Studies
, Humans
, Male
, Middle Aged
, Patient Education as Topic/methods
, Patient Satisfaction
, Prostatic Neoplasms/psychology
, Quality of Life
, Referral and Consultation/standards
, Telemedicine/standards
ABSTRACT
The infection process of intracellular opportunistic microsporidia involves the forcible eversion of a coiled hollow polar filament that pierces the host cell membrane, allowing the passage of infectious sporoplasm into the host cell cytoplasm. Although the exact mechanism of spore activation leading to polar filament discharge is unknown, we have shown that spore adherence to host cells, which is mediated by sulfated glycosaminoglycans, may play a vital role. When adherence is inhibited, host cell infection decreases, indicating a direct link between adherence and infection. The goal of this study was to evaluate the effects of exogenous divalent cations on microsporidia spore adherence and infection. Data generated using an in vitro spore adherence assay show that spore adherence is augmented by manganese (Mn2+) and magnesium (Mg2+), but not by calcium (Ca2+). However, each of the three divalent cations contributed to increased host cell infection when included in the assay. Finally, we show that Mn2+ and Mg2+ may activate a constituent on the microsporidia spore, not on the host cell, leading to higher infection efficiency. This report further supports recent evidence that spore adherence to the host cell surface is an important aspect of the microsporidial infection process.
Subject(s)
Cations, Divalent/pharmacology , Kidney/cytology , Kidney/microbiology , Microsporidia/physiology , Microsporidia/pathogenicity , Animals , Cell Adhesion/drug effects , Cell Line , Chlorocebus aethiops , Encephalitozoon/pathogenicity , Encephalitozoon/physiology , Microsporidia/drug effects , Rabbits , Spores, Fungal/physiology , Vero CellsABSTRACT
The aim of the study was to investigate the management of women with benign breast problems. A consecutive sample of women (n = 194) was assessed who presented to public or private sector providers. The main reasons for referral were breast lumps (62%); 56% of women who attended the public sector did not receive any recommendation compared to 40% who attended the private sector and clinical/general practitioner reviews were recommended to more women in the private sector (54%). Reasons for the discrepancy between public and private patients require further investigation.
Subject(s)
Breast Diseases/diagnosis , Private Sector , Public Sector , Quality of Health Care , Australia , Data Collection , Female , Humans , Referral and ConsultationABSTRACT
Microsporidia are obligate intracellular opportunistic protists that infect a wide variety of animals, including humans, via environmentally resistant spores. Infection requires that spores be in close proximity to host cells so that the hollow polar tube can pierce the cell membrane and inject the spore contents into the cell cytoplasm. Like other eukaryotic microbes, microsporidia may use specific mechanisms for adherence in order to achieve target cell proximity and increase the likelihood of successful infection. Our data show that Encephalitozoon intestinalis exploits sulfated glycans such as the cell surface glycosaminoglycans (GAGs) in selection of and attachment to host cells. When exogenous sulfated glycans are used as inhibitors in spore adherence assays, E. intestinalis spore adherence is reduced by as much as 88%. However, there is no inhibition when nonsulfated glycans are used, suggesting that E. intestinalis spores utilize sulfated host cell glycans in adherence. These studies were confirmed by exposure of host cells to xylopyranoside, which limits host cell surface GAGs, and sodium chlorate, which decreases surface sulfation. Spore adherence studies with CHO mutant cell lines that are deficient in either surface GAGs or surface heparan sulfate also confirmed the necessity of sulfated glycans. Furthermore, when spore adherence is inhibited, host cell infection is reduced, indicating a direct association between spore adherence and infectivity. These data show that E. intestinalis specifically adheres to target cells by way of sulfated host cell surface GAGs and that this mechanism serves to enhance infectivity.
Subject(s)
Cell Adhesion Molecules/physiology , Encephalitozoon/physiology , Encephalitozoonosis/metabolism , Glycosaminoglycans/physiology , Polysaccharides/physiology , Sulfur Compounds/metabolism , Animals , Cell Adhesion/physiology , Cells, Cultured , Cricetinae , Encephalitozoon/pathogenicity , Host-Parasite Interactions/physiology , Humans , Rabbits , Spores, Protozoan/physiologyABSTRACT
Normal lymphoid tissue development and function depend upon chemokine-directed cell migration. Since chemokines signal through heterotrimeric G-protein-coupled receptors, RGS proteins, which act as GTPase-activating proteins for Galpha subunits, likely fine tune the cellular responses to chemokines. Here we show that Rgs1(-/-) mice possess B cells that respond excessively and desensitize improperly to the chemokines CXCL12 and CXCL13. Many of the B-cell follicles in the spleens of Rgs1(-/-) mice have germinal centers even in the absence of immune stimulation. Furthermore, immunization of these mice leads to exaggerated germinal center formation; partial disruption of the normal architecture of the spleen and Peyer's patches; and abnormal trafficking of immunoglobulin-secreting cells. These results reveal the importance of a regulatory mechanism that limits and desensitizes chemokine receptor signaling.
Subject(s)
B-Lymphocytes/pathology , Lymphoid Tissue/pathology , Plasma Cells/pathology , RGS Proteins/immunology , Animals , B-Lymphocytes/drug effects , B-Lymphocytes/immunology , Chemokine CXCL12 , Chemokine CXCL13 , Chemokines/pharmacology , Chemokines, CXC/pharmacology , Chemotaxis/drug effects , Germinal Center/pathology , Mice , Mice, Knockout , Peyer's Patches/pathology , RGS Proteins/deficiency , RGS Proteins/physiology , Spleen/pathologyABSTRACT
Giardia lamblia, a worldwide cause of diarrhoea, must differentiate into environmentally resistant cysts for dissemination and completion of its life cycle. Although G. lamblia is an early diverging eukaryote, encystation involves many complex cellular changes including formation of the cyst wall that contains at least two cyst wall proteins, cyst wall proteins 1 and 2. Cwp genes are transcribed only during encystation. In this study, we examine the regulatory elements for the encystation-specific gene cwp2. The 64 bp immediately upstream of the cwp2 open reading frame (-64 to -1 relative to ATG) was shown to be sufficient for the encystation-specific expression of luciferase. To determine which region(s) within this 64 bp contributed to encystation-specific expression in vivo, a series of deletions were cloned into a Giardia luciferase expression vector and their ability to control encystation-specific expression of luciferase was assessed. Deletion of elements in the -64 to -23 region of the cwp2 promoter significantly increased expression of luciferase in vegetative trophozoites, suggesting that this area contains a negative cis-acting element. Deletions of elements from -23 to -10 led to decreased expression in encysting cells, suggesting that this region may contain positive cis-acting elements. When the A/T-rich initiator was deleted but the cis-acting elements (-64 to -10) were retained, encystation-specific expression of luciferase was maintained but an aberrant transcriptional start site was utilised. These results indicate that Giardia has developed a classic repressor mechanism(s) that allows tight, encystation-specific control by the cwp2 promoter.
Subject(s)
Gene Expression Regulation, Developmental , Giardia lamblia/genetics , Protozoan Proteins/genetics , Animals , Base Sequence , Giardia lamblia/growth & development , Molecular Sequence Data , Open Reading Frames/genetics , Plasmids/genetics , Promoter Regions, Genetic , Protozoan Proteins/physiology , RNA, Messenger/genetics , RNA, Protozoan/genetics , Sequence Deletion , TransfectionABSTRACT
PURPOSE: To examine the ability of standard dose-volume metrics to predict pulmonary function changes as measured by pulmonary function tests (PFTs) in a group of patients with non-small-cell lung cancer treated with nonconventional beam arrangements on a Phase I dose-escalation study. In addition, we wanted to examine the correlation between these metrics. MATERIALS AND METHODS: Forty-three patients received a median treatment dose of 76.9 Gy (range 63-102.9). Eight patients also received induction chemotherapy with cisplatin and vinorelbine. They all had pre- and posttreatment PFTs >/=3 months (median 6.2) after treatment. The volume of normal lung treated to >20 Gy, effective volume, and mean lung dose were calculated for both lungs for all patients. Linear regression analysis was performed to determine whether correlations existed between the metrics and changes in the PFTs. Additionally, the three metrics were compared with each other to assess the degree of intermetric correlation. RESULTS: No correlation was found between the volume of normal lung treated to >20 Gy, effective volume, and mean lung dose and changes in the PFTs. Subgroup analyses of patients without atelectasis before irradiation, Stage I and II disease, or treatment without induction chemotherapy were also performed. Again, no correlation was found between the dose-volume metrics and the PFT changes. The intermetric correlation was good among all three dose-volume metrics. CONCLUSIONS: In this relatively small series of patients, dose-volume metrics that correlate with the risk of pneumonitis did not provide a good model to predict early changes in pulmonary function as measured with PFTs.