Subsequent Ingestion Research Articles

Differential effects of graphene oxide nanosheets on Candida albicans phagocytosis by murine peritoneal macrophages

Macrophages, as effector cells involved in the innate and adaptive immunity, play a key role in the response to nanomaterials as graphene oxide (GO) and in their cellular uptake. The interactions at the interface of GO nanosheets, macrophages and microbial pathogens need to be assessed to determine the possible impairment of the immune system induced by biomedical treatments with this nanomaterial. Here, we have evaluated by flow cytometry and confocal microscopy the ability of murine peritoneal macrophages to phagocytose the fungal pathogen Candida albicans, alive or heat-killed, after treatment with poly(ethylene glycol-amine)-derivatized GO nanosheets (PEG-GO). After GO treatment, differences in fungal phagocytosis were observed between macrophages that had taken up GO nanosheets (GO+ population) and those that had not (GO− population). GO treatment increased the ingested alive yeasts in GO− macrophages, whereas phagocytosis diminished in the GO+ population. Ingestion of heat-killed yeasts was slightly higher in both GO− and GO+ populations when comparing with control macrophages. For the first time, we show that GO uptake by macrophages modulates its phagocytic capability, affecting differentially the subsequent ingestion of either alive or heat-killed yeasts. Enhanced ingestion of heat-killed yeast by GO-treated macrophages suggests a beneficial role of this nanomaterial for the clearance of dead microorganisms during infection.

Spot Sample Urine Specific Gravity Does Not Accurately Represent Small Decreases in Plasma Volume in Resting Healthy Males

ABSTRACTBackground: Urine specific gravity (USG) is often used to assess hydration status, particularly around athletic competition, but it is unknown whether high USG is indicative of plasma volume (PV) reduction (i.e., hypohydration). We tested the hypothesis that if high USG is reflective of reduced PV, subsequent fluid ingestion would increase PV.Purpose: The purpose of this study was to examine 24-hour changes in USG and PV in individuals presenting with high and low spot USG.Methods: Nineteen healthy males were provided food and water over 24 hours with a total water volume of 35 ml·kg−1 body mass. Absolute PV and blood volume (BV), measured using the CO-rebreathe technique, along with USG were measured before and after a 24-hour intervention period. Based on a preintervention morning spot USG, subjects were post hoc assigned to groups according to USG (≤1.020 or >1.020; low and high USG, respectively).Results: Despite presenting with an elevated spot USG (1.026 ± 0.004), subsequent fluid ingestion over 24 hours did not lead to changes (∆) in PV (−75 ± 234 ml) or BV (−156 ± 370 ml) in the high USG group (p > 0.05). However, a spot USG after the 24-hour intervention in this group decreased (p = 0.018) to a level indicating improved hydration status (1.017 ± 0.007). In the low USG group, there were no changes in PV (−39 ± 274 ml), BV (−82 ± 396 ml), or USG (0.003 ± 0.007) over the 24-hour fluid intervention (all p > 0.05).Conclusions: Despite a high preintervention USG and subsequent decrease after 24-hour fluid intake, measures of PV and BV were not indicative of this seemingly improved hydration status. This suggests that a highly concentrated spot sample USG and subsequent changes are not accurately representative of PV or BV.

Assessment of gastrointestinal nematode parasitism in dairy calves housed in calf hutches

Gastrointestinal nematodes (GIN) are an important cause of morbidity and production losses in cattle. Clinical infection with GIN can cause diarrhea and hypoalbuminemia, but subclinical infections are more prevalent, harder to recognize, and a greater threat to productivity. Emphasis in the dairy industry has been placed on management strategies to mitigate disease and productive losses caused by GIN infections in grazing heifers and adult cattle, but hutch calves have largely been left out of this discussion. Milk-fed dairy calves housed in hutches are presumed not to acquire GIN infection because transmission of GIN is thought to require exposure to a pasture environment and subsequent ingestion of contaminated forage. However, a recent assessment of fecal egg counts (FEC) in hutch calves for another research project revealed calves raised in hutches with unexpectedly high FEC. The objective of this study was to estimate the prevalence and magnitude of GIN in hutch calves on two calf ranches and to evaluate factors associated with the probability for calves to be parasitized.

Exploiting Uptake of Nanoparticles by Phagocytes for Cancer Treatment.

Many cancers including ovarian, pancreatic, colon, liver, and stomach cancers are largely confined to the peritoneal cavity. Peritoneal tumors are directly accessible by intraperitoneal injections. Previously we demonstrated that intraperitoneal injection of nanoparticles and subsequent ingestion by tumor-associated phagocytes can be used to either directly impact tumors or stimulate antitumor immune responses. Here we outline methods to specifically utilize iron oxide nanoparticles with the ID8-Defb29/Vegf-A murine ovarian cancer model and discuss the tendency of phagocytes to ingest nanoparticles and the potential of phagocytes to carry nanoparticles to tumors resulting in direct killing of tumor cells or stimulate antitumor immune responses in peritoneal cancers. This basic approach can be modified as needed for different types of tumors and nanoparticles.

Some observations on vortex-ring collisions upon inclined surfaces

This paper reports upon a laser-induced fluorescence visualization and time-resolved particle image velocimetry study to resolve the detailed dynamics associated with Re = 2000 and 4000 circular vortex rings colliding with 30°–75° inclined surfaces. Two-dimensional visualization results show that larger inclination angles lead to increasingly rapid size reduction in the primary vortex-ring core closer to the surface, faster formation of the secondary vortex-ring core, and subsequent ingestion by the former. In contrast, primary vortex-ring core further away from the surface becomes physically larger and incoherent more rapidly, with slower formation and entrainment of the secondary vortex-ring core. Interestingly, a vortex dipole and small vortex-ring-like structure are produced for the largest inclination angle of 75°, possibly due to vortex disconnection and reconnection processes. Results taken along the non-inclined plane show significant bulging of the primary vortex-ring cores when the inclination angle increases from 30° onwards. More importantly, additional vortex cores are observed to entwine with the primary vortex-ring core and provide strong direct evidence for the bi-helical vortex line flow mechanism put forward by Lim (Exp Fluids 7:453–463, 1989). Lastly, the behaviour of the primary and secondary vortex-ring cores further away from the surface is highly sensitive towards the state of the bi-helical lines compressed at that region. Strong compression driven by circumferential flows due to large inclination angles may explain the unique flow structures and behaviour observed for 75° inclination angle here.

Transient endophytic colonizations of plants improve the outcome of foliar applications of mycoinsecticides against chewing insects

The current work reports how spray application of entomopathogenic fungi on alfalfa, tomato and melon plants may cause an additional Spodoptera littoralis larvae mortality due to a temporal colonization of the leaves and subsequent ingestion of those leaves by the larvae. Most entomopathogenic fungi (EF) (Ascomycota: Hypocreales) endophytes seem to colonize their host plants in a non-systemic pattern, in which case at least a transient endophytic establishment of the fungus should be expected in treated areas after spray application. In this work, all strains were able to endophytically colonize roots, stems and leaves during the first 96h after inoculation. Whilst the treatment of S. littoralis larvae with a 108ml−1 conidial suspension resulted in moderate to high mortality rates for the Metarhizium brunneum EAMb 09/01-Su (41.7–50.0%) and Beauveria bassiana EABb 01/33-Su (66.7–76.6%) strains, respectively, an additive effect was detected when these larvae were also fed endophytically colonized alfalfa, tomato, and melon leaves, with mortality rates varying from 25.0% to 46.7% as a function of the host plant and total mortality rates in the combined treatment of 75–80% and 33–60% for B. bassiana and M. brunneum, respectively. Fungal outgrowth was not detected in any of the dead larvae feeding on colonized leaves, whereas traces of destruxin A were detected in 11% of the insects fed tomato discs endophytically colonized by M. brunneum. The combined effects of the fungal spray with the mortality caused by the feeding of insects on transient EF-colonized leaves have to be considered to estimate the real acute impact of field sprays with entomopathogenic fungi on chewing insects.

A quantitative risk ranking model to evaluate emerging organic contaminants in biosolid amended land and potential transport to drinking water

ABSTRACTA quantitative risk ranking model was developed for human exposure to emerging contaminants (EC) following treated municipal sewage sludge (“biosolids”) application to Irish agricultural land. The model encompasses the predicted environmental concentration (PEC) in soil, surface runoff, groundwater, and subsequent drinking water ingestion by humans. Human exposure and subsequent risk was estimated for 16 organic contaminants using a Monte Carlo simulation approach. Nonylphenols ranked the highest across three environmental compartments: concentration in soil (PECsoil), runoff (PECrunoff), and groundwater (PECgroundwater), which had mean values of 5.69 mg/kg, 1.15 × 10−2 µg/l, and 2.22 × 10−1 µg/l, respectively. Human health risk was estimated using the LC50 (chemical intake toxicity ratio, (RR)) as a toxicity endpoint combined with PECrunoff and PECgroundwater. NP ranked highest for LC50 combined with PECrunoff and PECgroundwater (mean RR values 1.10 × 10−4 and 2.40 × 10−3, respectively). The model highlighted triclocarban and triclosan as ECs requiring further investigation. A sensitivity analysis revealed that soil sorption coefficient and soil organic carbon were the most important parameters that affected model variance (correlation coefficient –0.89 and –0.30, respectively), highlighting the significance of contaminant and soil properties in influencing risk assessments. This model can help to prioritize emerging contaminants of concern requiring vigilance in environmental compartments.

Fluorescence Reports Intact Quantum Dot Uptake into Roots and Translocation to Leaves of Arabidopsis thaliana and Subsequent Ingestion by Insect Herbivores

We explored the impact of quantum dot (QD) coat characteristics on NP stability, uptake, and translocation in Arabidopsis thaliana, and subsequent transfer to primary consumers, Trichoplusia ni (T. ni). Arabidopsis was exposed to CdSe/CdZnS QDs with three different coatings: Poly(acrylic acid-ethylene glycol) (PAA-EG), polyethylenimine (PEI) and poly(maleic anhydride-alt-1-octadecene)-poly(ethylene glycol) (PMAO-PEG), which are anionic, cationic, and relatively neutral, respectively. PAA-EG-coated QDs were relatively stable and taken up from a hydroponic medium through both Arabidopsis leaf petioles and roots, without apparent aggregation, and showed generally uniform distribution in leaves. In contrast, PEI- and PMAO-PEG-coated QDs displayed destabilization in the hydroponic medium, and generated particulate fluorescence plant tissues, suggesting aggregation. PAA-EG QDs moved faster than PEI QDs through leaf petioles; however, 8-fold more cadmium accumulated in PEI QD-treated leaves than in those exposed to PAA-EG QDs, possibly due to PEI QD dissolution and direct metal uptake. T. ni caterpillars that fed on Arabidopsis exposed to QDs had reduced performance, and QD fluorescence was detected in both T. ni bodies and frass, demonstrating trophic transfer of intact QDs from plants to insects. Overall, this paper demonstrates that QD coat properties influence plant nanoparticle uptake and translocation and can impact transfer to herbivores.

Induction of hyperandrogenism in lean reproductive-age women stimulates proatherogenic inflammation.

We determined the effect of hyperandrogenemia as observed in polycystic ovary syndrome (PCOS) on fasting and glucose-stimulated proatherogenic inflammation markers in lean healthy reproductive-age women. Sixteen lean healthy ovulatory reproductive-age women were treated with 130 mg of DHEA or placebo (n=8 each) for 5 days. Interleukin-6 (IL-6) mRNA and IL-6 release from mononuclear cells (MNC), plasma IL-6 and C-reactive protein (CRP), and MNC-derived (matrix metalloproteinase-2) MMP-2 protein were quantified in the fasting state and 2 h after glucose ingestion, before and after treatment. Before treatment, subjects receiving dehydroepinadrosterone (DHEA) or placebo exhibited no differences in androgens, or any proatherogenic inflammation markers while fasting and after glucose ingestion. Compared with placebo, DHEA administration raised levels of testosterone, androstenedione, and DHEA-sulfate (DHEA-S), and increased the percent change from baseline in fasting IL-6 mRNA, IL-6 release, plasma IL-6, and CRP and MMP-2 protein. However, there were no differences in any of the proatherogenic inflammation markers following glucose ingestion after DHEA administration. We conclude that in lean reproductive-age women, proatherogenic inflammation in the fasting state increases after raising circulating androgens to levels observed in PCOS. However, this hyperandrogenemia-induced MNC activation does not provoke a similar response to subsequent glucose ingestion.

Uptake of Heavy Metals by Tomato (Lycopersicum esculentus) Grown on Soil Collected from Dumpsites in Ekiti State, South West, Nigeria

People in recent times have engaged in the habit of cultivating on abadoned dunpsites or soil collected from the existing ones because of their fertility. Lycopersicun esculentus is one of the vegetables that is mostly cultivated on such sites and also commonly consumed in Nigeria. Uptake of heavy metals by tomato (Lycopersicum esculentus) grown on soil collected from dumpsites located in Ekiti State, Nigeria was determined with a view to monitoring the pollutional status of the environment. Concentration of heavy metals were found in the range of Cd (27.20-55.74), Co (5.18-38.15), Cr (9.30-55.40), Cu (66.67-107.00), Fe (200.01-655.90), Pb (22.32-61.60), Mn (16.90-49.20), Ni (12.06-46.60), Sn (25.90-78.99) and Zn (7.54-91.10) all in mg/kg. The sequence of accumulation is in order of leaf>stem>root>fruit and Translocation factor (TF) values greater than 1 revealed that heavy metals were translocated into the aerial part of the plant. However, the study serves as pathway for the investigation of these heavy metals which may eventually enter the food chain and subsequent ingestion by man.

The effect of water temperature on drilling and ingestion rates of the dogwhelk Nucella lapillus feeding on Mytilus edulis mussels in the laboratory

In highly seasonal intertidal habitats, changes in temperature through the year may drive substantial shifts in feeding and growth rates of organisms. For the dogwhelk Nucella lapillus, attacking and consuming Mytilus edulis mussels can take hours or days, depending on temperature. Handling time of dogwhelks feeding on mussels is therefore greatly affected by ocean temperature. I recorded attack time in the laboratory, partitioned into drilling and consumption time, for juvenile dogwhelks across a range of seawater temperatures representative of field seawater temperatures during the main growing seasons of summer and autumn. The combined length of a drilling attack and subsequent ingestion time tripled across the 10 °C decline in water temperatures from July through November, driven primarily by an increase in ingestion time. The observed reduction in handling time, coupled with projected sea surface warming in New England by the end of the twenty-first century, could extend the length of the growing season for Nucella and subsequently have cascading effects on the prey community.

Proposed new mechanism for food and exercise induced anaphylaxis based on case studies

We present two cases of food and exercise-induced anaphylaxis (FEIA) in patients with a diagnosis of oral allergy syndrome (OAS) to the implicated foods. Patient A had FEIA attributed to fresh coriander and tomato and Patient B to fresh celery. These food allergens have been implicated in OAS and have structural antigenic similarity to that of birch and/or grass. Both patients’ allergies were confirmed by fresh skin prick tests. In both cases, strenuous exercise was antecedent to the systemic anaphylaxis reaction and subsequent ingestion without exercise produced only local symptoms of perioral pruritus. We review the current proposed mechanisms for food and exercise induced anaphylaxis to oral allergens and propose a novel and more biologically plausible mechanism. We hypothesize that the inhibitory effects of exercise on gastric acid secretion decreases the digestion of oral allergens and preserves structural integrity, thereby allowing continued systemic absorption of the allergen whether it be profilins, lipid transfer proteins, or other antigenic determinants.

Do favic patients resume fava beans ingestion later in their life, a study for this, and a new hypothesis for favism etiology

The etiology of favism remains unclear and the fate of favic patients has not previously been studied. Therefore, individuals who had experienced an episode of favism were studied regarding subsequent fava bean ingestion, including the reason for fava bean ingestion after the initial favic attack and any adverse reactions. In addition, a new hypothesis for the etiology of favism is proposed. From June 2005 to June 2012, a total of 38 patients with a history of favism were included in this study. Circumstances regarding the initial favic attack were obtained from medical records and patient interviews, and subsequent fava bean ingestion and recurrence of symptoms were investigated. Three of the 38 patients (7.9%) were female, and 35 (92.1%) were male. The mean age was 27.9 years (14-63 years). The first attack of favism occurred before 10 years of age for 31 patients (81.6%) and in the springtime for 35 patients (92.1%). Thirty-three patients (86.7%) regularly ate fava beans before the attack, and 35 (92.1%) resumed eating fava beans within 1-17 years after the attack without symptoms. Two patients (5.2%) experienced a single recurrence of symptoms. No evidence of hemolysis was found in the four patients checked after fava bean re-ingestion. Patients resumed eating fava bean for various reasons, and the recurrence of symptoms was uncommon. An infectious agent such as a virus may play a role in the development of favism.

A spectrophotometric technique for measuring particle ingestion by black fly larvae

AbstractA spectrophotometric technique was developed to provide insight into the feeding behavior of Simulium vittatum Zetterstedt (Diptera: Simuliidae) larvae. Larvae were exposed to water insoluble Neon Red particles (NRP) (DayGlo®) in a controlled current. The insoluble particles were available for capture by the cephalic fans of the larvae and subsequent ingestion. The length of gut occupied by the particles after a given exposure time was determined by visual inspection and measured with the aid of a dissecting microscope. Larvae were then homogenized in acetone to solubilize the particles. After filtration, the quantity of pigmented particles in the alimentary tract of the larvae was determined using spectrophotometric analysis. The quantity of particles per unit length of the alimentary tract was calculated. Experiments were conducted to determine the ideal concentration of NRP for obtaining an accurate measure of ingestion without interfering with normal larval feeding behavior. Larval mortality following ingestion of insecticidal proteins produced by Bacillus thuringiensis ssp. israelensis was used as an indirect measure of feeding behavior for these experiments. A concentration of 15 p.p.m. of NRP in the larval medium was the highest concentration used that did not interfere with larval mortality following exposure to the insecticidal proteins. Additional experiments demonstrated that components of the experimental matrix did not interfere with NRP absorbance. The final experiment revealed that the consumption of NRP and insecticidal proteins by larvae was influenced by clay and cellulose in the larval medium.

Sublethal pathology in bats associated with stress and volcanic activity on Montserrat, West Indies

Abstract The small Caribbean island of Montserrat has been battered by several hurricanes, and beginning in 1995, pyroclastic eruptions from the Soufriere Hills Volcano have destroyed the southern portion of the island. In addition to being incinerated by pyroclastic flows (300+°C), the bats of Montserrat also have had to contend with acid rain and the deposition of volcanic ash on leaves, fruits, and flowers and its subsequent ingestion by the bats. We document a dramatic decrease in the bat population and increases in several sublethal pathologies associated with the accumulation of ash across the island coincident with the onset of volcanic activity. Before 1995, less than 1% of the fruit bats exhibited evidence of unusual tooth wear. Since 1995, fruit bats have exhibited abnormal tooth wear advanced by the ingestion of volcanic ash while feeding and grooming. Damage to the teeth often includes ablation of the entire enamel crown and the exposure of the pulp cavity. Idiopathic hair loss was practically...

Upconversion nanoparticles dramatically promote plant growth without toxicity

Upconversion nanophosphors (UCNPs) have been widely used in bioscience and bioimaging, but the effect of UCNPs on plants and on animals after subsequent oral ingestion of the plants has not been studied previously. Herein, we investigate the effects of UCNPs on plant development using mung beans as a model. Incubation at a high UCNP concentration of 100 μg/mL led to growth inhibition, while a low concentration of 10 μg/mL promoted their development. Confocal imaging showed that UCNPs accumulated in the seeds and were transferred from seeds and roots to stems and leaves through the vascular system. Quantitative study by radioanalysis showed the distribution of UCNPs in the plant on the 5th day after incubation decreased in the order (root > seed > leaf > stem). After UCNP-treated bean sprouts were orally ingested by mice, UCNPs were completely excreted with feces, without absorption of residual amounts. Histology and hematology results showed no detectable toxic effects of UCNP-treated mung beans on exposed mice.

Phagocytes mediate targeting of iron oxide nanoparticles to tumors for cancer therapy

Nanotechnology has great potential to produce novel therapeutic strategies that target malignant cells through the ability of nanoparticles to get access to and be ingested by living cells. However its specificity for accumulation in tumors, which is the key factor that determines its efficacy, has always been a challenge. Here we tested a novel strategy to target and treat ovarian cancer, a representative peritoneal cancer, using iron oxide nanoparticles (IONPs) and an alternating magnetic field (AMF). Peritoneal tumors in general are directly accessible to nanoparticles administered intraperitoneally (IP), as opposed to the more commonly attempted intravenous (IV) administration. In addition, tumor-associated immunosuppressive phagocytes, a predominant cell population in the tumor microenvironment of almost all solid tumors, and cells that are critical for tumor progression, are constantly recruited to the tumor, and therefore could possibly function to bring nanoparticles to tumors. Here we demonstrate that tumor-associated peritoneal phagocytes ingest and carry IONPs specifically to tumors and that these specifically delivered nanoparticles can damage tumor cells after IONP-mediated hyperthermia generated by AMF. This illustrates therapeutic possibilities of intraperitoneal (IP) injection of nanoparticles and subsequent ingestion by tumor-associated phagocytes, to directly impact tumors or stimulate antitumor immune responses. This approach could use IONPs combined with AMF as done here, or other nanoparticles with cytotoxic potential. Overall, the data presented here support IP injection of nanoparticles to utilize peritoneal phagocytes as a delivery vehicle in association with IONP-mediated hyperthermia as therapeutic strategies for ovarian and other peritoneal cancers.

New evidence for assessing tetrahydrobiopterin (BH4) responsiveness

ObjectiveTo evaluate the protocol we propose for detecting BH4-responsive patients and the possibility of delimiting more precisely the population to be tested. MethodsWe recruited 102 phenylketonuric patients on a phenylalanine (Phe)-restricted diet. The initial stage of the protocol was a 24-h BH4 loading test involving Phe loading and subsequent ingestion of the cofactor, a 50% fall in blood Phe levels being considered a positive response. The non-responders at this stage then completed a one-week therapeutic test combining BH4 administration and daily protein intake meeting recommended dietary allowances, to assess whether the 24-h test had detected all responders. ResultsThe 24-h test detected almost all BH4 responders (30.3% of the 99 patients included in the analysis), with just two patients (2.0%) subsequently responding positively to the therapeutic test. The 24-h test did not give any false positive results. ConclusionsThe 24-h BH4 loading test is clinically useful for screening phenylketonuric patients. Specifically, 95% of patients with Phe levels <700μmol/L, and none with Phe levels >1500μmol/L were BH4-responsive. Given these results, we conclude that patients with Phe levels<700μmol/L or>1500μmol/L probably do not need to be tested, prioritising the identification of BH4-responsiveness among individuals with intermediate Phe concentrations, between the aforementioned values. Additionally, our results suggest that the therapeutic test only needs to be performed in cases where the reduction in blood Phe levels after cofactor administration is within the range 40%–50%.

Pharyngeal trauma: Two unique case reports

The neck is a complex pathway for numerous critical structures and is defined by layers of fascial planes and spaces. Traumatic interruption of these planes can occur with injury to any of the mucosal structures within the head and neck, and is often seen as a consequence of pharyngeal injury. Here, the identification and management of two interesting and unique cases of penetrating oropharyngeal trauma are discussed: oropharyngeal trauma following abuse, and a self-inflicted pharyngeal wound with subsequent foreign body ingestion. We also review the literature regarding diagnosis, treatment, and management of traumatic pharyngeal perforation, and discuss possible complications.

An assessment of potential public health risk associated with the extended survival of indicator and pathogenic bacteria in freshwater lake sediments

Microcosm studies were performed to evaluate the survival of Escherichia coli, Salmonella paratyphi and Vibrio parahaemolyticus in water and sediment collected from the freshwater region of Vembanad Lake (9'35 °N 76'25 °E) along the south west coast of India. All three test microorganisms showed significantly (p < 0.01) higher survival in sediment compared to overlying water. The survival in different sediment types with different particle size and organic carbon content revealed that sediment with small particle size and high organic carbon content could enhance their extended survival (p < 0.05). The results indicate that sediments of the Lake could act as a reservoir of pathogenic bacteria and exhibit a potential health hazard from possible resuspension and subsequent ingestion during recreational activities. Therefore, the assessment of bacterial concentration in freshwater Lake sediments used for contact and non contact recreation has of considerable significance for the proper assessment of microbial pollution of the overlying water, and for the management and protection of related health risk at specific recreational sites. Besides, assessment of the bacterial concentration in sediments can be used as a relatively stable indicator of long term mean bacterial concentration in the water column above.