Review of quorum-quenching probiotics: A promising non-antibiotic-based strategy for sustainable aquaculture

The emergence of antibiotic-resistant bacteria (ARBs) and genes (ARGs) in aquaculture underscores the urgent need for alternative veterinary strategies to combat antimicrobial resistance (AMR). These measures are vital to reduce the likelihood of entering a post-antibiotic era. Identifying environmentally friendly biotechnological solutions to prevent and treat bacterial diseases is crucial for the sustainability of aquaculture and for minimizing the use of antimicrobials, especially antibiotics. The development of probiotics with quorum-quenching (QQ) capabilities presents a promising non-antibiotic strategy for sustainable aquaculture. Recent research has demonstrated the effectiveness of QQ probiotics (QQPs) against a range of significant fish pathogens in aquaculture. QQ disrupts microbial communication (quorum sensing, QS) by inhibiting the production, replication, and detection of signalling molecules, thereby reducing bacterial virulence factors. With their targeted anti-virulence approach, QQPs have substantial promise as a potential alternative to antibiotics. The application of QQPs in aquaculture, however, is still in its early stages and requires additional research. Key challenges include determining the optimal dosage and treatment regimens, understanding the long-term effects, and integrating QQPs with other disease control methods in diverse aquaculture systems. This review scrutinizes the current literature on antibiotic usage, AMR prevalence in aquaculture, QQ mechanisms and the application of QQPs as a sustainable alternative to antibiotics.

Identification of natural antiviral drug candidates against Tilapia Lake Virus: Computational drug design approaches

Tilapia Lake Virus (TiLV) is a disease that affects tilapia fish, causing a high rate of sudden death at any stage in their life cycle. Unfortunately, there are currently no effective antiviral drugs or vaccines to prevent or control the progression of this disease. Researchers have discovered that the CRM1 protein plays a critical function in the development and spreading of animal viruses. By inhibiting CRM1, the virus's spread in commercial fish farms can be suppressed. With this in mind, this study intended to identify potential antiviral drugs from two different tropical mangrove plants from tropical regions: Heritiera fomes and Ceriops candolleana. To identify promising compounds that target the CRM1 protein, a computer-aided drug discovery approach is employed containing molecular docking, ADME (absorption, distribution, metabolism and excretion) analysis, toxicity assessment as well as molecular dynamics (MD) simulation. To estimate binding affinities of all phytochemicals, molecular docking is used and the top three candidate compounds with the highest docking scores were selected, which are CID107876 (-8.3 Kcal/mol), CID12795736 (-8.2 Kcal/mol), and CID12303662 (-7.9 Kcal/mol). We also evaluated the ADME and toxicity properties of these compounds. Finally, MD simulation was conducted to analyze the stability of the protein-ligand complex structures and confirm the suitability of these compounds. The computational study demonstrated that the phytochemicals found in H. fomes and C. candolleana could potentially serve as important inhibitors of TiLV, offering practical utility. However, further in vivo investigations are necessary to investigate and potentially confirm the effectiveness of these compounds as antiviral drugs against the virus TiLV.

Coastal aquaculture in Bangladesh: Sundarbans's role against climate change

The Sundarbans, a natural shield on earth, is one and only place that has many noteworthy environmental and geographical values with breathtaking natural beauties. Near the Sundarbans area, proliferation of aquaculture in this delta contributes appreciably to the national economy. Although aquaculture has become a means of daily livelihood, this sector is nevertheless threatened by a complex of climate change impacts. Cyclones, rising temperatures, rising sea levels, coastal flooding, and erosion make coastal farming difficult. As a panacea, the Sundarbans can play a critical role in preserving coastal aquaculture. As noticed, forests have high potential to recover from unusual consequences of climate change. Practicing safe aquaculture should be opted to refrain from endangering the Sundarbans. This review addressed various climate change impacts on coastal farming and identified the capabilities of the Sundarbans to protect coastal aquaculture from calamitous impacts. Findings show clues for researchers to analyze problems, consequences, and mitigations.

Initial experience with a continuous mechanical aspiration system for thrombus removal before percutaneous coronary intervention

OBJECTIVES

Here we investigate the safety and efficacy of a continuous mechanical aspiration system when used before percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS).

BACKGROUND

Historically, trials of routine manual aspiration thrombectomy in ACS patients have reported mixed results. This may be due to the technical limitations of manual aspiration, which suffers from decreasing vacuum power as aspiration is performed.

METHODS

This is a retrospective case series of all patients treated with continuous mechanical aspiration (Indigo CAT RX Aspiration System; Penumbra Inc.) before PCI between August 2017 and July 2020 at five centers in the United States. Data regarding angiographic assessments, procedure, and safety were examined.

RESULTS

Seventy-two patients (mean age 60 ± 12.5 years, 34.7% female) with ST Elevation Myocardial Infarction (STEMI) (80.6%) or Non-ST Elevation Myocardial Infarction (NSTEMI) (19.4%) were included. Target vessels were the right coronary (43.1%), left anterior descending (33.3%), and left circumflex (23.6%). Preprocedure, 94.4% had a high thrombus burden (thrombolysis in myocardial infarction [TIMI] thrombus grade ≥ 3). Median aspiration time was 35 s and median access-to-reperfusion time was 10 min. After CAT RX alone, 86.1% had complete perfusion (TIMI flow grade 3). After the procedure, 94.4% had TIMI thrombus grade <3% and 97.2% had TIMI flow grade 3. There were no cases of ischemic stroke. Cardiovascular mortality at 30 days was 1.4%.

CONCLUSIONS

In our initial experience, aspirating thrombus from ACS patients using the Indigo CAT RX Aspiration System before PCI was safe and effective for reducing thrombus burden and restoring flow.

Single and Multi-Strain Probiotics Supplementation in Commercially Prominent Finfish Aquaculture: Review of the Current Knowledge

The Nile tilapia Oreochromis niloticus, Atlantic salmon Salmo salar, rainbow trout Oncorhynchus mykiss, olive flounder Paralichthys olivaceus, common carp Cyprinus carpio, grass carp Ctenopharyngodon idella and rohu carp Labeo rohita are farmed commercially worldwide. Production of these important finfishes is rapidly expanding, and intensive culture practices can lead to stress in fish, often reducing resistance to infectious diseases. Antibiotics and other drugs are routinely used for the treatment of diseases and sometimes applied preventatively to combat microbial pathogens. This strategy is responsible for the emergence and spread of antimicrobial resistance, mass killing of environmental/beneficial bacteria, and residual effects in humans. As an alternative, the administration of probiotics has gained acceptance for disease control in aquaculture. Probiotics have been found to improve growth, feed utilization, immunological status, disease resistance, and to promote transcriptomic profiles and internal microbial balance of host organisms. The present review discusses the effects of single and multi-strain probiotics on growth, immunity, heamato-biochemical parameters, and disease resistance of the above-mentioned finfishes. The application and outcome of probiotics in the field or open pond system, gaps in existing knowledge, and issues worthy of further research are also highlighted.

Determination of the Most Efficient Household Technique for the Reduction of Pesticide Residues from Raw Fish Muscles

Substantial quantities of pesticides are routinely applied to enhance agricultural crop production. Pesticides used in this way continuously accumulate in the environment and in foods. Harvested crops contain pesticide residues at various concentrations, with potential harmful impacts on human health. Hence, it is of value to identify techniques for the effective decontamination of tainted foods. However, cleaning with water or household agents, e.g., acetic acid and sodium bicarbonate, are recognized treatments for the efficient degradation of pesticides from vegetables and fruits. There is an apparent void of information about the decontamination treatments for raw fishes using household agents that are affordable for all classes of consumers. Hence, the present study was performed to determine the most efficient household technique for reducing pesticide residue levels from precooked raw fish to ensure the utmost food safety. Fish muscles of four species of fishes, viz., Clarias gariepinus, Channa striatus, Anabas testudineus and Trichogaster trichopterus, were treated with six treatments: washing with running tap water (T1), dipping in normal water (T2), dipping in 2% salt solution (T3), dipping in 2% vinegar (T4), dipping in 0.1% sodium bicarbonate solution (T5) as well as dipping in 0.1% sodium bicarbonate solution + 2% vinegar + 2% salt solution + lemon juice (T6), as fish muscle is the major consumable portion of fish. The current study demonstrated that the removal percentage of lindane, heptachlor, aldrin, endosulfan, dieldrin, endrin, DDT, methoxychlor and cypermethrin residues against the treated household treatments, in downward order, were soaking in 0.1% sodium bicarbonate solution + 2% vinegar + 2% salt solution + lemon juice solution (T6) > soaking in 2% vinegar (T4) solution > soaking in 0.1% sodium bicarbonate (T5) solution > soaking in 2% salt (T3) solution > washing with running tap water (T1) > soaking in stable normal water (T2). The treatment of raw fish muscle samples by soaking them in 0.1% sodium bicarbonate solution + 2% vinegar + 2% salt solution + lemon juice was found to be the most efficient household treatment, performing significant reductions (%) in pesticide concentration: 72−80% (p < 0.05) in Channa striata, 71−79% (p < 0.05) in Clarias gariepinus, 74−80% (p < 0.05) in Anabas testudineus as well as 78−81% (p < 0.05) in Trichogaster trichopterus before cooking.

Comparison of three stationary phases in the separation of polyphenyls by liquid chromatography

We present herein new analytical protocols for the separation and structural elucidation of polyphenyls. Three commercially available chromatographic stationary phases are compared in the separation of these non-polar, unfunctionalized, positional isomers. Baseline separation of nine terphenyl and quaterphenyl isomers is achieved in under ten minutes using a rapid gradient elution HPLC method. Complete separation of these, and a further five polyphenyls, is demonstrated. We finally present a linear correlation between solvent accessible surface area and the retention times of these closely related compounds.

Probiotic Treatment Enhances Pre-feeding Larval Development and Early Survival in Zebrafish Danio rerio

The growth and development of healthy culture subjects are essential in increasing productivity in the aquaculture industry. A primary determinant of aquatic animal productivity is the ambient microbial population. If an aquatic animal's microbiome is diverse, with bacteria favoring beneficial over pathogenic species, the health and growth of the animal (i.e., fish or crustacean) can be substantially improved. Embryonic and newly hatched Zebrafish Danio rerio larvae were reared in the presence of (1) water from the broodstock culture tank as a control, (2) a probiotic solution containing 19 strains of live lactic acid bacteria (LAB), or (3) an antibiotic (AB) solution with amoxycillin. Developmental parameters were monitored until 10 d postfertilization. Bacteria present in the water and larvae were cultured and identified by sequencing the V4 hypervariable region of bacterial 16S ribosomal RNA. Probiotic-treated larvae showed significant increases in every measured morphological parameter and in survival compared to the controls and AB-treated larvae, including TL, eye development, and swim bladder development before first feeding. Staining with DASPEI (2-(4-[dimethylamino]styryl)-N-ethylpyridinium iodide) produced fluorescence, revealing increased mitochondrial activity in the gastrointestinal tracts of probiotic-treated larvae and reflecting advancement of initial metabolic function. Probiotic-treated larvae showed accelerated yolk absorption, resulting in increased nutrient mobilization and growth. Microbial analyses revealed a greater concentration of bacteria in larvae in response to the probiotic treatment compared to the other two treatments. Species identified in all three treatments included Pseudomonas spp. and Aeromonas spp. (Proteobacteria). The second most diverse and abundant microbiome was seen in controls, whereas AB-treated larvae had the least diverse microbiome. All treatments revealed the presence of proteobacteria, but an AB-resistant pathogenic bacterium (Stenotrophomonas maltophilia) was identified in the AB group. These results reveal that the presence of LAB and other bacteria favorably influenced early larval growth, development, digestive function, and survival in Zebrafish even before the onset of feeding.

Using new solvatochromic parameters to investigate dye–solvent interactions

Solvatochromic behaviours of triazine substituted dyes were evaluated using a novel approach derived from the red shift index (RsI) and associated solvation energy (ASE). These parameters were used to describe the solvation trends of the dye–solvent interactions based on their polarity changes. The concept demonstrates the effect of substituent changes on the triazine scaffold and the induced solvent polarity changes as solvated dyes go through the HOMO–LUMO (highest occupied molecular orbital-lowest uncopied molecular orbital) phases. Primarily, these phases were characterised by evaluating the wavelength of the absorption and emission spectra in different solvents, which, in conjunction with the recently reported computational approaches, provides a well-adjusted model for predicting spectra polarity changes between the dye (solute) and the solvent. Based on the results from this study, predictive polarity changes on the triazine scaffold in different solvents can be empirically monitored both in ground and excited states. Moreover, the solvatochromic parameters can be extended to evaluate the predictive behaviours of different spectra dyes.

Determination of Median Lethal Concentration (LC50) for Endosulfan, Heptachlor and Dieldrin Pesticides to African Catfish, Clarias gariepinus and Their Impact on Its Behavioral Patterns and Histopathological Responses

Pesticides such as endosulfan, heptachlor and dieldrin persist in aquatic environments as a result of their resistance to biodegradation. However, there is no adequate information about the toxicity of endosulfan, heptachlor and dieldrin to the aquatic organism, African catfish (Clarias gariepinus)-a high valued widely distributed commercially interesting species. The current experiment was performed with the aim to determine the median lethal concentration (LC50) of endosulfan, heptachlor and dieldrin to African catfish (Clarias gariepinus); their behavioral abnormalities and histopathological alterations in several vital organs. A total of 324 juvenile fish were exposed for 96 h to six concentrations of endosulfan and dieldrin at 0, 0.001, 0.002, 0.004, 0.008 and 0.016 ppm, and to heptachlor at concentrations of 0, 0.02, 0.04, 0.08, 0.16 and 0.32 ppm for dose-response tests. The study demonstrated that the species is highly susceptible to those contaminants showing a number of behavioral abnormalities and histopathological changes in gill, liver and muscle. The 96-h LC50 value of endosulfan, dieldrin and heptachlor for the African catfish was found as 0.004 (0.001-0.01) mg/L, 0.006 mg/L and 0.056 (0.006-0.144) mg/L, respectively. Abnormal behaviors such as erratic jerky swimming, frequent surfacing movement with gulping of air, secretion of mucus on the body and gills were observed in response to the increasing exposure concentrations. Histopathological alterations of liver, gill and muscle tissues were demonstrated as vacuolization in hepatocytes, congestion of red blood cells (RBCs) in hepatic portal vein; deformed secondary lamellae and disintegrated myotomes with disintegrated epidermis, respectively. These findings are important to monitor and responsibly manage pesticide use in and around C. gariepinus aquacultural areas.

A systematic review of the effects of temperature and precipitation on pollen concentrations and season timing, and implications for human health

Climate and weather directly impact plant phenology, affecting airborne pollen. The objective of this systematic review is to examine the impacts of meteorological variables on airborne pollen concentrations and pollen season timing. Using PRISMA methodology, we reviewed literature that assessed whether there was a relationship between local temperature and precipitation and measured airborne pollen. The search strategy included terms related to pollen, trends or measurements, and season timing. For inclusion, studies must have conducted a correlation analysis of at least 5 years of airborne pollen data to local meteorological data and report quantitative results. Data from peer-reviewed articles were extracted on the correlations between seven pollen indicators (main pollen season start date, end date, peak date, and length, annual pollen integral, average daily pollen concentration, and peak pollen concentration), and two meteorological variables (temperature and precipitation). Ninety-three articles were included in the analysis out of 9,679 articles screened. Overall, warmer temperatures correlated with earlier and longer pollen seasons and higher pollen concentrations. Precipitation had varying effects on pollen concentration and pollen season timing indicators. Increased precipitation may have a short-term effect causing low pollen concentrations potentially due to "wash out" effect. Long-term effects of precipitation varied for trees and weeds and had a positive correlation with grass pollen levels. With increases in temperature due to climate change, pollen seasons for some taxa in some regions may start earlier, last longer, and be more intense, which may be associated with adverse health impacts, as pollen exposure has well-known health effects in sensitized individuals.

Profiling the Neoplasm Microenvironment of Silica Nanomaterial-Derived Scaffolds of Single, 2-, and 3-Composite Systems

The challenges with scaffold profiling of cell-based assay includes accelerated cancer cell proliferation, induced scaffold toxicity, and identifying irrelevant cancer cell-based assays in batch assessments. This study investigates profiling carcinoma of breast cancer cells of MCF-7 model systems using silica nanoparticles scaffold sourced from synthetic materials and plant extracts. Herein, the engineered tissue scaffolds were used to create temporary structures for cancer cell attachments, differentiation, and subsequently to assess the metabolic activity of the cancer cell colonies. The cell viability of the cancer cells was assessed using the tetrazolium compound (MTS reagent), which was reduced to colored formazan, to indicate metabolically active cancer cells in a proliferating assay. We aimed to develop cancer cell-based scaffolds that not only mimic the neoplastic activity, but that also allowed synergistic interaction with cisplatin for in vitro assay screening.

A Computational Comparative Study for the Spectroscopic Evaluation of Triazine Derivative Dyes in Implicit Solvation Model Systems Using Semi-Empirical and Time-Dependent Density Functional Theory Approaches

The spectroscopic data for a range of cyclopenta-[d][1,2,3]-triazine derivative dyes have been evaluated using various standard computational approaches. Absorption data of these dyes were obtained using the ZINDO/S semi-empirical model for vertical excitation energies of structures optimised with the AM1, PM3, and PM6 methods. These studies were conducted under vacuum and solution states using the polarisation continuum model (PCM) for implicit solvation in the linear response model. The accuracy, along with the modest computational costs of using the ZINDO/S prediction, combined with the PM3 optimisation method for absorption data was reliable. While a higher computational cost is required for the time-dependent density functional theory (TDDFT), this method offers a reliable method for calculating both the absorption and emission data for the dyes studied (using vertical and adiabatic excitation energies, respectively) via state-specific solvation. This research demonstrates the potential of computational approaches utilising solvation in evaluating the spectroscopic properties of dyes in the rational design of fluorescent probes.

Batch Effect Adjustment to Lower the Drug Attrition Rate of MCF-7 Breast Cancer Cells Exposed to Silica Nanomaterial-Derived Scaffolds

Drug attrition rate is the calculation or measure of the clinical efficacy of a candidate drug on a screen platform for a specific period. Determining the attrition rate of a prospective cancer drug is a reliable way of testing the clinical efficacy. A low attrition rate in the last phase of a preclinical trial increases the success of a drug discovery process. It has been reported that the attrition rates of antineoplastic drugs are much higher than for other therapeutic drugs. Among the factors identified for the high attrition rates in antineoplastic drugs are the nature of the screen-based platforms involving human-derived xenografts, extracellular matrix-derived scaffold systems, and the synthetic scaffolds, which all have propensity to proliferate tumor cells at faster rates than in vivo primary tumors. Other factors that affect the high attrition rates are induced scaffold toxicity and the use of assays that are irrelevant, yet affect data processing. These factors contribute to the wide variation in data and systematic errors. As a result, it becomes imperative to filter batch variations and to standardize the data. Importantly, understanding the interplay between the biological milieu and scaffold connections is also crucial. Here the cell viability of MCF-7 (breast cancer cell line) cells exposed to different scaffolds were screened before cisplatin dosing using the calculated p-values. The statistical significance (p-value) of data was calculated using the one-way analysis of variance, with the p-value set as: 0 < p < 0.06. In addition, the half-maximal inhibitory concentration (IC₅₀) of the different scaffolds exposed to MCF-7 cells were calculated with the probit extension model and cumulative distribution (%) of the extension data. The chemotherapeutic dose (cisplatin, 56 mg/m²) reduced the cell viability of MCF-7 cells to 5% within 24 h on the scaffold developed from silica nanoparticles (SNPs) and polyethylene glycol (PEG) formulation (SNP:PEG) mixtures with a ratio of 1:10, respectively.

Mucosal immune response of Nile tilapia Oreochromis niloticus during Gyrodactylus cichlidarum infection

Monogenean Gyrodactylus cichlidarum can cause severe mortality of Nile tilapia (Oreochromis niloticus) fry. To date, reports about mucosal immunity of O. niloticus against this parasite have been rare. In order to explore the mucosal immunity of Nile tilapia against G. cichlidarum infection, the expressions of six adaptive immune-related genes and the contents of specific immunoglobulin IgM and IgT in the skin-associated lymphoid tissues (SALT) were dynamically analyzed after primary and secondary infections. The abundances of G. cichlidarum on the hosts after secondary infection were lower than those after primary parasite infection, which implied that hosts could initiate immune protection against G. cichlidarum reinfection to some degree. The transcription levels of TCR-β and CD4 genes in the skin tissue were significantly up-regulated after primary G. cichlidarum infection, while genes pIgR and IgT were only detected with significant up-regulations during secondary infection. With the exception of pIgR, which had remarkably higher expression in the fish with low parasite loads, all other genes studied tended to have higher mRNA level in the fish with higher parasite loads. The specific IgM content in the skin mucus increased significantly on the 2nd day after the primary exposure, higher than the corresponding value during the secondary exposure, and had significantly positive correlation with the parasite loads during the first parasite infection. These results manifested that acquired immune responses in the SALT of Nile tilapia participated in the resistance against G. cichlidarum infection, underscoring the involvement of mucosal immunity in fish against monogenean infection, and suggesting potential prophylactic treatment of gyrodactylid disease of tilapia.

Combating Antibiotic-Resistant Gram-Negative Bacteria Strains with Tetracycline-Conjugated Carbon Nanoparticles

Nontoxic carbon nanoparticle samples prepared by both bottom-up and top-down approaches do not inhibit Gram-negative bacterial growth, indicating excellent biocompatibilities. However, cell growth inhibitory efficacies increase considerably when the carbon nanoparticles are conjugated with the antibiotic tetracycline. In tetracycline-resistant bacteria, these efficacies can approach tenfold higher activities when compared to tetracycline alone. No structural abnormality such as membrane disruptions is evident in the tested bacterial strains; this is in contrast with other nanocarbon systems such as graphene oxides, carbon nanotubes, and amine-functionalized carbon nanoparticles which do exhibit membrane disruptions. In comparison, the tetracycline-conjugated carbon nanoparticles induce membrane perturbations (but not membrane disruptions), inhibiting bacterial efflux mechanisms. It is proposed that when tetracycline is conjugated to the surface of carbon nanoparticles, it functions to direct the nanoparticles to membrane-associated tetracycline efflux pumps, thereby blocking and subsequently inhibiting their function. The conjugation between biocompatible carbon nanoparticles and subtherapeutic but well-established antibiotic molecules may provide hybrid antibiotic assembly strategies resulting in effective multidrug efflux inhibition for combating antibiotic resistance.

Circulating tumour cells: a broad perspective

Circulating tumour cells (CTCs) have recently been identified as valuable biomarkers for diagnostic and prognostic evaluations, as well for monitoring therapeutic responses to treatments. CTCs are rare cells which may be present as one CTC surrounded by approximately 1 million white blood cells and 1 billion red blood cells per millilitre of peripheral blood. Despite the various challenges in CTC detection, considerable progress in detection methods have been documented in recent times, particularly for methodologies incorporating nanomaterial-based platforms and/or integrated microfluidics. Herein, we summarize the importance of CTCs as biological markers for tumour detection, highlight their mechanism of cellular invasion and discuss the various challenges associated with CTC research, including vulnerability, heterogeneity, phenotypicity and size differences. In addition, we describe nanomaterial agents used for electrochemistry and surface plasmon resonance applications, which have recently been used to selectively capture cancer cells and amplify signals for CTC detection. The intrinsic properties of nanomaterials have also recently been exploited to achieve photothermal destruction of cancer cells. This review describes recent advancements and future perspectives in the CTC field.

Cancer biomarker profiling using nanozyme containing iron oxide loaded with gold particles

Nanozymes are nanomaterials with intrinsic magnetism and superparamagnetic properties. In the presence of an external magnet, nanozyme particles aggregate and redisperse without a foreign attraction. We evaluated the performances of nanozyme by changing the biosensing platforms and substituting other biological variants for a complete cancer assay detection. We investigated the expression of morphological variants in the transmission of signals using an electrochemical method. The signal responses, including signal enhancement with the nanozyme (Au-Fe₂O₃), showed a wide capturing range (greater than 80%, from 10² to 10⁵ cells ml^-1 in phosphate-buffered saline buffer, pH 7.4). The platform showed a fast response time within a dynamic range of 10-10⁵ cells ml^-1 for the investigated T47D cancer cell line. We also obtained higher responses for anti-HER2 (human epidermal receptor 2)/streptavidin interface as the biosensing electrode in the presence of T47D cancer cells. The positive assay produced a sixfold increase in current output compared to the negative target or negative biological variant. We calculated the limit of detection at 0.4 U ml^-1, and of quantitation at 4 U ml^-1 (units per millilitre). However, blood volume amounts in clinical settings may constrain diagnosis and increase detection limit value significantly.

The Effect of Thermal Treatment on the Hydrogen-Storage Properties of PIM-1

There has been recent interest in polymers of intrinsic microporosity (PIMs) for solid-state hydrogen-storage materials; however, the gas-sorption properties and conditions for hydrogen uptake are relatively unexplored. PIM-1 has been synthesised using the condensation reaction between 3,3,3,3-tetramethyl-1,1-spirobisindane-5,5,6,6-tetraol and 2,3,5,6-tetrafluorophthalonitrile as precursors. The synthesised PIM-1 was annealed at different temperatures for varying times and then characterised for hydrogen uptake at both ambient and cryogenic temperatures. The excess hydrogen PCT isotherms have been measured to high pressure (320 bar) for the first time and the effect of different annealing conditions on the hydrogen capacity is reported.

Improving the Gas-Separation Properties of PVAc-Zeolite 4A Mixed-Matrix Membranes through Nano-Sizing and Silanation of the Zeolite

Mixed-matrix membranes containing synthesised nano-sized zeolite 4A and PVAc were fabricated to investigate the effect of zeolite loading on membrane morphology, polymer-filler interaction, thermal stability and gas separation properties. SEM studies revealed that, although the membranes with 40 wt % nano-sized zeolite particles were distributed uniformly through the polymer matrix without voids, the membranes with 15 wt % zeolite loading showed agglomeration. With increasing zeolite content, the thermal stability improved, the permeability decreased and the selectivity increased. The effect of silanation on dispersion of 15 wt % zeolite 4A nanoparticles through PVAc was investigated by post-synthesis modification of the zeolite with 3-Aminopropyl(diethoxy)methylsilane. Modification of the nanoparticles improved their dispersion in PVAc, resulting in higher thermal stability than the corresponding unmodified zeolite membrane. Modification also decreased the rigidity of the membrane. Partial pore blockage of the modified zeolite nanoparticles after silanation caused a further decrease in permeability, compared to the 15 wt % unmodified zeolite membrane.

Generating Oxygen Vacancies in MnO Hexagonal Sheets for Ultralong Life Lithium Storage with High Capacity

The polar surface of (001) wurtzite-structured MnO possesses substantial electrostatic instabilities that facilitate a wurtzite to graphene-like sheet transformation during the lithiation/delithiation process when used in battery technologies. This transformation results in cycle instability and loss of cell efficiency. In this work, we synthesized MnO hexagonal sheets (HSs) possessing abundant oxygen vacancy defects (MnO-Vo HSs) by pyrolyzing and reducing MnCO₃ HSs under an atmosphere of Ar/H₂. The oxygen vacancies (Vos) were generated in the reduction process and have been characterized using a range of techniques: X-ray absorption fine structure, electron-spin resonance, X-ray absorption near edge structure, Artemis modeling, and R space Feff modeling. The data arising from these analyses inform us that the introduction of one Vo defect within each O atom layer can reduce the charge density by 3.2 × 10^-19 C, balancing the internal nonzero dipole moment and rendering the wurtzite structure more stable, so inhibiting the change to a graphene-like structure. Density function theory calculations demonstrate that the incorporation of Vos sites significantly improves the charge accumulation around Li atoms and increases Li⁺ adsorption energies (-2.720 eV). When used as an anode material for lithium ion batteries, the MnO-Vo HSs exhibit high specific capacity (1228.3 mAh g^-1 at 0.1 A g^-1) and excellent cell cycling stabilities (∼88.1% capacity retention after 1000 continuous charge/discharge cycles at 1.0 A g^-1).

Expression of immune-related genes of Nile tilapia Oreochromis niloticus after Gyrodactylus cichlidarum and Cichlidogyrus sclerosus infections demonstrating immunosupression in coinfection

Gyrodactylus cichlidarum and Cichlidogyrus sclerosus, two monogenean ectoparasite species commonly found on the body surface and gills of Nile tilapia (Oreochromis niloticus) respectively, inflicted considerable economic losses in intensive tilapia farming. In order to explore the immune response of tilapia against these two species of monogeneans, expression patterns of five immune-related genes were studied after singular G. cichlidarum or C. sclerosus infection and their coinfection. The transcription levels of IL-1β were up-regulated in the skin after G. cichlidarum infection, reaching a peak at day 5 PI, and in the gills after C. sclerosus infection (peaking at day 8 PI), with significant elevation only detected in the gills after high-dose C. sclerosus infection. A trend favoring increased gill TNF-α expression at day 8 PI of C. sclerosus infection was statistically significant only in the low-dose infection group. TNF-α expression in the skin did not change significantly after G. cichlidarum infection. TGF-β had extremely up-regulated expressions in the gills at day 8 PI after both high- and low-dose C. sclerosus infections, but its significantly promoted expression in the skin was observed only after infection of high-dose G. cichlidarum. Significantly increased expressions of HSP70 and COX-2 in the skin were detected after high-dose G. cichlidarum infections. In comparison to singular infection with either G. cichlidarum or C. sclerosus, concurrent infection resulted in significantly advanced expression of TGF-β in both skin and gills, and lower expressions at day 8 PI, and similar patterns were observed in the expression of IL-1β and TNF-α in the gills. G. cichlidarum infection on the body surface significantly down-regulated the expressions of TNF-α, TGF-β and COX-2 in the gills. In addition, the intensity of G. cichlidarum was significantly positively correlated with that of C. sclerosus (correlation index 0.922, p = 0.000) at day 2 PI under concurrent infection. These results contribute to the understanding of mucosal immunity of fish against monogenean infection, particularly when two monogenean species infect concurrently.

Adjuvant chemotherapy in patients with stage I endometrioid or clear cell ovarian cancer in the platinum era: a Surveillance, Epidemiology, and End Results Cohort Study, 2000-2013

Background

We sought to evaluate the impact of adjuvant chemotherapy on overall survival (OS) in patients with stage I endometrioid epithelial ovarian cancer (EEOC) or ovarian clear cell cancer (OCCC) using a national database.

Patients and methods

The Surveillance, Epidemiology, and End Results database was used to identify patients diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage I EEOC or OCCC from 2000 to 2013. We sought to identify predictors of chemotherapy use and to assess the impact of chemotherapy on OS in these patients. OS was compared using the log-rank test and the Cox proportional hazards model.

Results

In all, 3552 patients with FIGO stage I EEOC and 1995 patients with stage I OCCC were identified. Of the 1600 patients (45%) with EEOC who underwent adjuvant chemotherapy, the 5-year OS rate was 90%, compared with 89% for those who did not undergo adjuvant chemotherapy (P = 0.807). Of the 1374 (69%) patients with OCCC who underwent adjuvant chemotherapy, the 5-year OS rate was 85%, compared with 83% (P = 0.439) for those who did not undergo adjuvant chemotherapy. Chemotherapy use was associated with younger age, higher substage, and more recent year of diagnosis for both the EEOC and OCCC groups. Only in the subgroup of patients with FIGO substage IC, grade 3 EEOC (n = 282) was chemotherapy associated with an improved 5-year OS-81% compared with 62% (P = 0.003) in untreated patients (HR: 0.583; 95% CI: 0.359-0.949; P = 0.030). In patients with OCCC, there was no significant effect of adjuvant chemotherapy on OS in any substage.

Conclusions

Adjuvant chemotherapy was associated with improved OS only in patients with substage IC, grade 3 EEOC. In stage I OCCC, adjuvant chemotherapy was not associated with improved OS.

Pediatric Medial Subperiosteal Orbital Abscess: Medical Management Where Possible

Background

Controversy exists about the optimal management of subperiosteal orbital abscesses (SPOAs) in pediatric patients. Some otolaryngologists advocate immediate surgical drainage while others recommend medical management initially and reserve surgery for nonresponders. We hypothesized that patients who can be managed without surgery have identifiable features on presentation that may aid in predicting their response to medical therapy.

Methods

A retrospective chart review was performed on all patients ≤18 years of age who were admitted to the University of Iowa between 1984 and 2001 with findings consistent with an SPOA on computed tomography imaging. Patients were divided into two groups: group I received medical treatment only while group II underwent surgical drainage of the abscess. Presenting features were compared between the two groups.

Results

Forty-two patients were identified with 17 group I patients and 25 group II patients. All patients had resolution of their SPOA and favorable outcomes. The following variables attained significance: group I patients were younger than group II patients (5.1 years versus 11 years; p < 0.0001), had less restriction of ocular motility (—1.0 versus —2.3), and were hospitalized for fewer days (6.5 days versus 9.6 days; p = 0.011). The following clinical variables did not vary significantly between the groups: gender, side of abscess, temperature, total white blood cell count, neutrophil count, chemosis, visual acuity, and proptosis. Culture results predominantly showed growth of anaerobic organisms (7/23). With increasing age, there was an increase in the number of organisms cultured (p = 0.005).

Conclusion

A subset of patients with SPOAs can be managed medically. These patients tend to be younger and present with minimal restriction of ocular motility. (American Journal of Rhinology 18, 321–327, 2004)

Lack of Significant Correlation between Rhinosinusitis Symptoms and Specific Regions of Sinus Computer Tomography Scans

Background

The sinonasal computer tomography (CT) scan is frequently used to help confirm the diagnosis of rhinosinusitis. However, little data exist correlating patient symptoms with CT findings.

Methods

Immediately preceding CT of the sinuses, 94 subjects without evidence of trauma, nasal tumors, or previous sinus surgery completed the Rhinosinusitis Outcome Measure 31 symptom questionnaire and were asked to locate areas of facial pain or pressure. CT scans were graded according to the Lund-MacKay system, and agger nasi and ethmoid bulla cells were measured. Data from CT scans and symptom/pain questionnaire responses were analyzed for significant correlations.

Results

No correlation was identified when comparing total Lund-MacKay scores, opacification of individual sinuses, and size of the agger nasi and ethmoid bulla cells with the Rhinosinusitis Outcome Measure 31 subset scores and areas of facial pain or pressure.

Conclusion

The sinus CT scan is a necessary tool for preoperative planning; however, it should not be used to predict symptoms or to localize areas responsible for facial pain or pressure.

Impact of Conventional and Three-Dimensional Thallium-Technetium Scans on Surgery for Primary Hyperparathyroidism

Twenty-nine patients with primary hyperparathyroidism underwent double-tracer subtraction scanning after injection of 201Tl as thallous chloride for thyroid and parathyroid images followed by 99mtechnetium as sodium pertechnetate for thyroid images prior to surgical exploration of the neck. The operative findings were correlated with the scans. All 23 adenomas (100%) and 13 of 18 (72%) hyperplastic glands were correctly localized. The ability of the scan to identify abnormal parathyroids was determined by the gland mass rather than whether the tissue was adenomatous or hyperplastic as all 32 (100%) abnormal glands weighing more than 180 mg were successfully localized in contrast to four of nine (44%) glands weighing less than 180 mg. An additional technique, in which emission tomography was carried out after subtraction scintigraphy, was used on 11 patients in the series. In all 11, the site of a single abnormal gland was predicted by the conventional subtraction scan: in nine of these patients, emission tomography provided additional localization of the gland in the anteroposterior plane.

Effect of buffer composition on PNA–RNA hybridization studied in the microfluidic microarray chip

Herein, we report that peptide nucleic acid sequences (PNAs) have been used as the probe species for detection of RNA and that a microfluidic microarray (MMA) chip is used as the platform for detection of hybridizations between immobilized PNA probes and RNA targets. The RNA targets used are derived from influenza A sequences. This paper discusses the optimization of two probe technologies used for RNA detection and investigates how the composition of the probe buffer and the content of the hybridization solution can influence the overall results. Our data show that the PNA probe is a better choice than the DNA probe when there is low salt in the probe buffer composition. Furthermore, we show that the absence of salt (NaCl) in the hybridization buffer does not hinder the detection of RNA sequences. The results provide evidence that PNA probes are superior to DNA probes in term of sensitivity and adaptability, as PNA immobilization and PNA–RNA hybridization are less affected by salt content in the reaction buffers unlike DNA probes.

Phylogeography of Angiostrongylus cantonensis (Nematoda: Angiostrongylidae) in southern China and some surrounding areas

Angiostrongylus cantonensis is of increasing public health importance as the main zoonotic pathogen causing eosinophilic meningitis or meningoencephalitis, which has been documented all over the world. However, there are very limited studies about its phylogeography and spread pattern. In the present study, the phylogeography of A. cantonensis in southern China (including Taiwan) and partial areas of Southeast Asia were studied based on the sequences of complete mitochondrial cytochrome b (Cytb) gene. A total of 520 individuals of A. cantonensis obtained from 13 localities were sequenced for the analyses and grouped into 42 defined haplotypes. The phylogenetic tree (NJ tree and BI tree) revealed a characteristic distribution pattern of the four main lineages, with detectable geographic structure. Genetic differentiation among populations was significant, but demographic expansion could not be detected by either neutrality tests or mismatch distribution analysis, which implied a low gene flow among the local populations in different regions where the samples were collected. Two unique lineages of the A. cantonensis population in Taiwan were detected, which suggests its multiple origin in the island. Populations in Hekou (China) and Laos showed the highest genetic diversities, which were supported by both genetic diversity indices and AMOVA. These results together infer that the area around Thailand or Hekou in Yunnan province, China are the most likely origins of Angiostrongylus cantonensis.

Since it was described in 1935, more than 2800 cases of the disease have reportedly been caused by A. cantonensis worldwide, primarily in tropical and subtropical regions. Despite a relevant body of research on pathology, diagnosis and treatment, little is known about the phylogeography of A. cantonensis. Since southern China is one of the endemic regions, we performed this experiment to reveal the distribution pattern of A. cantonensis in southern China based on mitochondrial Cytb data. Our results revealed a unique pattern probably shaped by the biological features of its hosts and geographical barriers, simultaneously reflecting a low gene flow among populations. Nevertheless, the connective consanguinity between some locations (Taiwan and Southeast Asia) provides new evidence of the impact on its dispersal as influenced by human activities, indicating the emerging need of an effective strategy to control this helminth. In addition to the corresponding investigation on its hosts, more attention to the situation in southwest China and Southeast Asia is suggested to facilitate the understanding of the phylogeography of A. cantonensis.

Insect Analogue to the Lotus Leaf: A Planthopper Wing Membrane Incorporating a Low-Adhesion, Nonwetting, Superhydrophobic, Bactericidal, and Biocompatible Surface

Nature has produced many intriguing and spectacular surfaces at the micro- and nanoscales. These small surface decorations act for a singular or, in most cases, a range of functions. The minute landscape found on the lotus leaf is one such example, displaying antiwetting behavior and low adhesion with foreign particulate matter. Indeed the lotus leaf has often been considered the "benchmark" for such properties. One could expect that there are animal counterparts of this self-drying and self-cleaning surface system. In this study, we show that the planthopper insect wing (Desudaba danae) exhibits a remarkable architectural similarity to the lotus leaf surface. Not only does the wing demonstrate a topographical likeness, but some surface properties are also expressed, such as nonwetting behavior and low adhering forces with contaminants. In addition, the insect-wing cuticle exhibits an antibacterial property in which Gram-negative bacteria (Porphyromonas gingivalis) are killed over many consecutive waves of attacks over 7 days. In contrast, eukaryote cell associations, upon contact with the insect membrane, lead to a formation of integrated cell sheets (e.g., among human stem cells (SHED-MSC) and human dermal fibroblasts (HDF)). The multifunctional features of the insect membrane provide a potential natural template for man-made applications in which specific control of liquid, solid, and biological contacts is desired and required. Moreover, the planthopper wing cuticle provides a "new" natural surface with which numerous interfacial properties can be explored for a range of comparative studies with both natural and man-made materials.

Role of oxygen-containing functional groups in forest fire-generated and pyrolytic chars for immobilization of copper and nickel

Char as a carbon-rich material, can be produced under pyrolytic conditions, wildfires or prescribed burn offs for fire management. The objective of this study was to elucidate mechanistic interactions of copper (Cu²⁺) and nickel (Ni²⁺) with different chars produced by pyrolysis (green waste, GW; blue-Mallee, BM) and forest fires (fresh-burnt by prescribed fire, FC; aged char produced by wild fire, AC). The pyrolytic chars were more effective sorbents of Cu²⁺ (∼11 times) and Ni²⁺ (∼5 times) compared with the forest fire chars. Both cross-polarization (CPMAS-NMR) and Bloch decay (BDMAS-NMR) ¹³C NMR spectroscopies showed that forest fire chars have higher woody components (aromatic functional groups) and lower polar groups (e.g. O-alkyl C) compared with the pyrolytic chars. The polarity index was greater in the pyrolytic chars (0.99-1.34) than in the fire-generated chars (0.98-1.15), while aromaticity was lower in the former than in the latter. Fourier transform infrared (FTIR) and Raman spectroscopies indicated the binding of carbonate and phosphate with both Cu²⁺ and Ni²⁺ in all chars, but with a greater extent in pyrolytic than forest fire-generated chars. These findings have demonstrated the key role of char's oxygen-containing functional groups in determining their sorption capacity for the Cu²⁺ and Ni²⁺ in contaminated lands.

Yellow-Emitting Carbon Nanodots and Their Flexible and Transparent Films for White LEDs

We report carbon nanodots that can be utilized as effective color converting phosphors for the production of white light-emitting diodes (LEDs). Blue-excitable and yellow-emitting carbon nanodots, functionalized with 3-(imidazolidin-2-on-1-yl)propylmethyldimethoxysilane (IPMDS)-derived moieties (IS-CDs), are synthesized by a novel one-pot reaction in which the products from the initial reaction occurring between urea and 3-(2-aminoethylamino)propylmethyl-dimethoxysilane (AEPMDS) are further treated with citric acid. Distinctive from the majority of carbon nanodots reported previously, IS-CDs emit at 560 nm, under 460 nm excitation, with a quantum yield of 44%. Preliminary toxicity studies, assessed by the Artemia franciscana nauplii (brine shrimp larvae) bioassay, indicate that IS-CDs are largely nontoxic. Furthermore, the IS-CDs form flexible and transparent films without the need of encapsulating agents, and the solid films retain the optical properties of solvated IS-CDs. These features indicate an immense potential for the IS-CDs as an environmental-friendly, blue-excitable carbon nanodot-based phosphor in solid-state lighting devices.

Defect Graphene as a Trifunctional Catalyst for Electrochemical Reactions

Defects derived by the removal of heteroatoms from graphene are demonstrated, both experimentally and theoretically, to be effective for all three basic electrochemical reactions, e.g., oxygen reduction (ORR), oxygen evolution (OER), and hydrogen evolution (HER). Density function theory calculations further reveal that the different types of defects are essential for the individual electrocatalytic activity for ORR, OER, and HER, respectively.

Randomized clinical trial into the impact of rigid foot orthoses on balance parameters in excessively pronated feet

Objective: To evaluate the effect of rigid foot orthoses on balance parameters in participants with clinically diagnosed excessively pronated feet.

Design: Randomized clinical trial.

Setting: University biomechanics laboratory.

Participants: Thirty female and 20 male healthy participants (mean 23.89 ± 2.2 years old) with excessively pronated feet, according to a validated foot classification system were randomly assigned to either a control or intervention group.

Interventions: Balance testing was performed using the Balance Performance Monitor with an over-the-counter rigid foot orthoses.

Main outcome measures: Standing balance in the form of mean balance (measures the participants ability to stand with an even load), medial–lateral sway and anterior–posterior sway. All participants were measured while standing bipedally.

Results: There was no significant mean difference in balance scores between the control and intervention group at baseline. After four weeks the results demonstrated no significant differences between mean) balance ( p > 0.05) and anterior–posterior sway ( p > 0.05). However, there was a reduction with the intervention group in medial–lateral sway ( p > 0.02).

Conclusion: The use of foot orthoses in the current study may have improved postural control by stabilizing the rear foot and thus maintaining balance. By the same argument, the benefits of limiting excessive foot pronation may contribute to effective control of internal rotation of the tibia and thereby reduce counter-rotatory motion at the knee and lower leg and maintain balance.

Safety and Outcomes of Balloon Catheter Sinusotomy: A Multicenter 24-Week Analysis in 115 Patients

OBJECTIVE: The aim of this study was to further evaluate the safety and effectiveness of balloon catheter devices to dilate obstructed sinus ostia/perform sinusotomy.

METHODS: Through a prospective, multicenter evaluation, safety was assessed by rate of adverse events, patency was determined by endoscopic examination, and sinus symptoms were determined by the Sino-Nasal Outcome Test (SNOT 20).

RESULTS: At the conclusion of the 24-week analysis, endoscopy determined that the sinusotomy was patent in 80.5% (247 of 307) sinuses and nonpatent in 1.6% (5 of 307), and could not determine ostial patency status in 17.9% (55 of 307). Of the ostia visualized on endoscopy, 98% were patent (247 of 252), while 2% (5 of 252) were considered nonpatent. SNOT 20 scores showed consistent symptomatic improvement over baseline. Revision treatment was required in 3 sinuses (3 of 307 sinuses, 0.98%) in 3 patients (3 of 109 patients, 2.75%).

CONCLUSION: Balloon catheter technology appears safe and effective in relieving ostial obstruction. Patients were pleased and indicated that they experienced symptomatic improvement.

Defect-driven oxygen reduction reaction (ORR) of carbon without any element doping

A “pure” porous carbon, lacking any elemental doping, exhibits excellent activity of oxygen reduction.

Phylogeography of Tetrancistrum nebulosi (Monogenea, Dactylogyridae) on the host of mottled spinefoot (Siganus fuscescens) in the South China Sea, inferred from mitochondrial COI and ND2 genes

To examine the phylogeographical pattern of Tetrancistrum nebulosi (Monogenea, Dactylogyridae) in the South China Sea, fragments of mitochondrial cytochrome c oxidase subunit I and NADH dehydrogenase subunit 2 genes were obtained for 220 individuals collected from 8 localities along the southeast coast of China and 1 locality in Terengganu, Malaysia. Based on these two genes, two and three distinct clades with geographic signals were revealed on the phylogenetic trees respectively. The divergence between these clades was estimated to occur in the late Pleistocene. Analysis of molecular variance and pairwise F_ST suggested a high rate of gene flow among individuals sampled from the Chinese coast, but with obvious genetic differentiation from the Malaysian population. Mismatch distribution and neutrality tests indicated that the T. nebulosi population experienced expansion in Pleistocene low sea level periods. Vicariance was considered to account for the genetic divergence between Chinese and Malaysian populations, while sea level fluctuations and mainland-island connections during glacial cycles were associated with the slight genetic divergence between the populations along the mainland coast of China and those off Sanya. On the contrary, oceanographic circulations and host migration could lead to genetic homogeneity of populations distributed along the mainland coast of China.

Identification of Potent and Selective Inhibitors of the Plasmodium falciparum M18 Aspartyl Aminopeptidase (PfM18AAP) of Human Malaria via High-Throughput Screening

The target of this study, the PfM18 aspartyl aminopeptidase (PfM18AAP), is the only AAP present in the genome of the malaria parasite Plasmodium falciparum. PfM18AAP is a metallo-exopeptidase that exclusively cleaves N-terminal acidic amino acids glutamate and aspartate. It is expressed in parasite cytoplasm and may function in concert with other aminopeptidases in protein degradation, of, for example, hemoglobin. Previous antisense knockdown experiments identified a lethal phenotype associated with PfM18AAP, suggesting that it is a valid target for new antimalaria therapies. To identify inhibitors of PfM18AAP function, a fluorescence enzymatic assay was developed using recombinant PfM18AAP enzyme and a fluorogenic peptide substrate (H-Glu-NHMec). This was screened against the Molecular Libraries Probe Production Centers Network collection of ~292,000 compounds (the Molecular Libraries Small Molecule Repository). A cathepsin L1 (CTSL1) enzyme-based assay was developed and used as a counter screen to identify compounds with nonspecific activity. Enzymology and phenotypic assays were used to determine mechanism of action and efficacy of selective and potent compounds identified from high-throughput screening. Two structurally related compounds, CID 6852389 and CID 23724194, yielded micromolar potency and were inactive in CTSL1 titration experiments (IC50>59.6 µM). As measured by the K(i) assay, both compounds demonstrated micromolar noncompetitive inhibition in the PfM18AAP enzyme assay. Both CID 6852389 and CID 23724194 demonstrated potency in malaria growth assays (IC504 µM and 1.3 µM, respectively).

Molecular typing of environmental and clinical strains of Vibrio vulnificus isolated in the northeastern USA

Vibrio vulnificus is a ubiquitous marine bacterium that is responsible for infections and some seafood-related illnesses and deaths in the United States, mainly in individuals with compromised health status in the Gulf of Mexico region. Most phylogenetic studies focus on V. vulnificus strains isolated in the southern United States, but almost no genetic data are available on northeastern bacterial isolates of clinical or environmental origin. Our goal in this study was to examine the genetic diversity of environmental strains isolated from commercially-produced oysters and in clinical strains of known pathogenicity in northeastern United States. We conducted analyses of a total of eighty-three strains of V. vulnificus, including 18 clinical strains known to be pathogenic. A polyphasic, molecular-typing approach was carried out, based upon established biotypes, vcg, CPS, 16S rRNA types and three other genes possibly associated with virulence (arylsulfatase A, mtlABC, and nanA). An established Multi Locus Sequence Typing (MLST) method was also performed. Phylogenetic analyses of these markers and MLST results produced similar patterns of clustering of strains into two main lineages (we categorized as 'LI' and 'LII'), with clinical and environmental strains clustering together in both lineages. Lineage LII was comprised primarily but not entirely of clinical bacterial isolates. Putative virulence markers were present in both clinical and environmental strains. These results suggest that some northeastern environmental strains of V. vulnificus are phylogenetically close to clinical strains and probably are capable of virulence. Further studies are necessary to assess the risk of human illness from consuming raw oysters harvested in the northeastern US.

Enhanced gametocyte formation in erythrocyte progenitor cells: a site-specific adaptation by Plasmodium falciparum

Gametocytogenesis by Plasmodium falciparum is essential for transmission of the parasite from human to mosquito, yet developing gametocytes lack expression of surface proteins required for cytoadherence. Therefore, elimination from the circulation should occur unless they are sequestered in regions of low blood flow such as the extracellular spaces of the bone marrow. Our data indicate that gametocytogenesis is enhanced in the presence of erythroid progenitors found within the bone marrow. Furthermore, atomic force microscopy indicates that developing gametocytes undergo remarkable shifts in their erythrocyte membrane elasticity, which may allow them to be retained within the bone marrow until maturation.