SUBCLINICAL EPILEPTIC SEIZURES—Impairment of Motor Performance and Derivative Difficulties

Modern clinical observations have greatly expanded the conception of the characteristics of the various kinds of epilepsy. By simultaneously recording electroencephalograms and the performance of simple motor tasks, it has been possible to demonstrate the effects of epileptic seizures not detectable by unaided observation and not noted by the patient. The effects of these subclinical seizures have been manifested variously—by a lengthening of the time between stimulus and reaction, by inaccuracies of response to stimuli, or by total cessation of performance.From this study it is suggested that subclinical seizures probably play a role in producing some of the psychiatric conditions associated with the convulsive disorders, as well as primary behavior disturbances and undifferentiated mental deficiency. It is also suggested that such subclinical seizures may possibly contribute to the characteristics of some cases of criminality and antisocial reactions and schizophrenic reactions.     

Fungistatic Performance of 10,10′-Oxybisphenoxarsine in Exterior Latex and Asphalt Coatings

10, 10'-Oxybisphenoxarsine has been found to be outstanding in its activity against bacteria and fungi. Parallel tests with known fungistats for comparison (2,3,4,6-tetrachlorophenol and phenylmercuric acetate) have demonstrated its superior activity and persistence in an exterior acrylate paint film and in an asphalt coating. In view of its superior antimicrobial activity and its persistence, it can be used in applications in which there is no danger of its ingestion. Further field trials are in progress to evaluate 10, 10'oxybisphenoxarsine in paint, asphalt, wood, and in marine pilings.     

Drinking and Flying: Does Alcohol Consumption Affect the Flight and Echolocation Performance of Phyllostomid Bats?

Background

In the wild, frugivorous and nectarivorous bats often eat fermenting fruits and nectar, and thus may consume levels of ethanol that could induce inebriation. To understand if consumption of ethanol by bats alters their access to food and general survival requires examination of behavioural responses to its ingestion, as well as assessment of interspecific variation in those responses. We predicted that bats fed ethanol would show impaired flight and echolocation behaviour compared to bats fed control sugar water, and that there would be behavioural differences among species.

Methodology/Principal Findings

We fed wild caught Artibeus jamaicensis, A. lituratus, A. phaeotis, Carollia sowelli, Glossophaga soricina, and Sturnira lilium (Chiroptera, Phyllostomidae) sugar water (44 g of table sugar in 500 ml of water) or sugar water with ethanol before challenging them to fly through an obstacle course while we simultaneously recorded their echolocation calls. We used bat saliva, a non-invasive proxy, to measure blood ethanol concentrations ranging from 0 to >0.3% immediately before flight trials. Flight performance and echolocation behaviour were not significantly affected by consumption of ethanol, but species differed in their blood alcohol concentrations after consuming it.

Conclusions/Significance

The bats we studied display a tolerance for ethanol that could have ramifications for the adaptive radiation of frugivorous and nectarivorous bats by allowing them to use ephemeral food resources over a wide span of time. By sampling across phyllostomid genera, we show that patterns of apparent ethanol tolerance in New World bats are broad, and thus may have been an important early step in the evolution of frugivory and nectarivory in these animals.     

Sleepiness and Performance in Response to Repeated Sleep Restriction and Subsequent Recovery during Semi‐Laboratory Conditions

There is an ongoing debate of how best to measure the effects of sleep loss in a reliable and feasible way, partly because well controlled laboratory studies and field studies have come to different conclusions. The aims of the present study were to investigate both sleepiness and performance in response to long‐term sleep restriction and recovery in a semi‐laboratory environment, investigate order effects (i.e., whether levels return to baseline) in a study with seven days of recovery, and characterize individual differences in tolerance to restricted sleep. Nine healthy men (age 23–28 yrs) participated in the protocol, which included one habituation day (sleep 23:00–07:00 h), two baseline days (23:00–07:00 h), five days with restricted sleep (03:00–07:00 h), and seven recovery days (23:00–07:00 h). Participants went outdoors at least twice each day. Reaction‐time tests were performed at 08:00, 14:00, and 20:00 h each day in the laboratory. Sleepiness was self‐rated by the Karolinska Sleepiness Scale (KSS) after each test. The mixed‐effect regression models showed that each day of restricted sleep resulted in an increase of sleepiness by 0.64±.05 KSS units (a nine‐step scale, p<.001), increase of median reaction times of 6.6±1.6 ms (p=.003), and increase of lapses/test of 0.69±.16 ms (p<.001). Seven days of recovery allowed participants to return to the baseline for sleepiness and median reaction time, but not for lapses. The individual differences were larger for performance measures than for sleepiness; the between‐subject standard deviation for the random intercept was in the magnitude of the effects of 1.1 days of restricted sleep for sleepiness, 6.6 days of restricted sleep for median reaction time, and 3.2 days for lapses. In conclusion, the present study shows that sleepiness is closely related to sleep pressure, while performance measures, to a larger extent, appear determined by specific individual traits. Moreover, it is suggested to measure sleepiness in a standardized situation so as to minimize the influences of contextual factors.     

Ginkgo Biloba Extract Ameliorates Oxidative Phosphorylation Performance and Rescues Aβ-Induced Failure

Background

Energy deficiency and mitochondrial failure have been recognized as a prominent, early event in Alzheimer''s disease (AD). Recently, we demonstrated that chronic exposure to amyloid-beta (Aβ) in human neuroblastoma cells over-expressing human wild-type amyloid precursor protein (APP) resulted in (i) activity changes of complexes III and IV of the oxidative phosphorylation system (OXPHOS) and in (ii) a drop of ATP levels which may finally instigate loss of synapses and neuronal cell death in AD. Therefore, the aim of the present study was to investigate whether standardized Ginkgo biloba extract LI 1370 (GBE) is able to rescue Aβ-induced defects in energy metabolism.

Methodology/Principal Findings

We used a high-resolution respiratory protocol to evaluate OXPHOS respiratory capacity under physiological condition in control (stably transfected with the empty vector) and APP cells after treatment with GBE. In addition, oxygen consumption of isolated mitochondria, activities of mitochondrial respiratory enzymes, ATP and reactive oxygen species (ROS) levels as well as mitochondrial membrane mass and mitochondrial DNA content were determined. We observed a general antioxidant effect of GBE leading to an increase of the coupling state of mitochondria as well as energy homeostasis and a reduction of ROS levels in control cells and in APP cells. GBE effect on OXPHOS was even preserved in mitochondria after isolation from treated cells. Moreover, these functional data were paralleled by an up-regulation of mitochondrial DNA. Improvement of the OXPHOS efficiency was stronger in APP cells than in control cells. In APP cells, the GBE-induced amelioration of oxygen consumption most likely arose from the modulation and respective normalization of the Aβ-induced disturbance in the activity of mitochondrial complexes III and IV restoring impaired ATP levels possibly through decreasing Aβ and oxidative stress level.

Conclusions/Significance

Although the underlying molecular mechanisms of the mode of action of GBE remain to be determined, our study clearly highlights the beneficial effect of GBE on the cellular OXPHOS performance and restoration of Aβ-induced mitochondrial dysfunction.     

Formulation and Performance Characterization of Radio-Sterilized “Progestin-Only” Microparticles Intended for Contraception

The aim of this study was to formulate and characterize a microparticulate system of progestin-only contraceptive. Another objective was to evaluate the effect of gamma radio-sterilization on in vitro and in vivo drug release characteristics. Levonorgestrel (LNG) microspheres were fabricated using poly(lactide-co-glycolide) (PLGA) by a novel solvent evaporation technique. The formulation was optimized for drug/polymer ratio, emulsifier concentration, and process variables like speed of agitation and evaporation method. The drug to polymer ratio of 1:5 gave the optimum encapsulation efficiency. Speed of agitation influenced the spherical shape of the microparticles, lower speeds yielding less spherical particles. The speed did not have a significant influence on the drug payloads. A combination of stabilizers viz. methyl cellulose and poly vinyl alcohol with in-water solvent evaporation technique yielded microparticles without any free drug crystals on the surface. This aspect significantly eliminated the in vitro dissolution “burst effect”. The residual solvent content was well within the regulatory limits. The microparticles passed the test for sterility and absence of pyrogens. In vitro dissolution conducted on the product before and after gamma radiation sterilization at 2.5 Mrad indicated no significant difference in the drug release patterns. The drug release followed zero-order kinetics in both static and agitation conditions of dissolution testing. The in vivo studies conducted in rabbits exhibited LNG release up to 1 month duration with drug levels maintained within the effective therapeutic window.     

Performance and fatigue during repeated sprints: what is the appropriate sprint dose?

When testing the ability of sportsmen to repeat maximal intensity efforts, or when designing specific training exercises to improve it, fatigue during repeated sprints is usually investigated through a number of sprints identical for all subjects, which induces a high intersubject variability in performance decrement in a typical heterogeneous group of athletes (e.g., team sport group, students, and research protocol volunteers). Our aim was to quantify the amplitude of the reduction in this variability when individualizing the sprint dose, that is, when requiring subjects to perform the number of sprints necessary to reach a target level of performance decrement. Fifteen healthy men performed 6-second sprints on a cycle ergometer with 24 seconds of rest until exhaustion or until 20 repetitions in case no failure occurred. Peak power output (PPO) was measured and a fatigue index (FI) computed. The variability in PPO decrement was compared between the 10th sprint and the sprint at which subject reached the target FI of 10%. Individual FI values after the 10th sprint were 14.6 ± 6.9 vs. 11.1 ± 1.2%, when individualizing the sprint dose, which corresponded to coefficients of interindividual variability of ～47.3 and ～10.8%, respectively. Individualizing the sprint dose substantially reduced intersubject variability in performance decrement, enabling a more standardized state of fatigue in repeated-sprints protocols designed to induce fatigue and test or train this specific repeated-sprint ability in a heterogeneous group of athletes. A direct feedback on the values of performance parameters is necessary between each sprint for the experimenter to set this individualized sprint dose.     

Pollinator Shift and Reproductive Performance of the Qinghai–Tibetan Plateau Endemic and Endangered Swertia przewalskii (Gentianaceae)

Reproductive failure results in many plant species becoming endangered. However, little is known of how and to what extent pollinator shifts affect reproductive performance of endangered species as a result of the artificial introduction of alien insects. In this study we examined breeding systems, visitor species, visiting frequency and seed set coefficients of Swertia przewalskii in two years that had different dominant pollinator species (native vs. alien). Flowers of this species were protandrous and herkogamous and insects were needed for the production of seeds. The stigmatic receptivity of this species was shorter than for other gentians. No significant difference in seed set coefficient was found for hand-pollinated plants between the two years, indicating that pollinator shift only had a minor effect on this plant’s breeding system. The commonest pollinators in 2002 were native bumblebees, alien honeybees and occasional solitary bees, however, only alien honeybees were observed in 2004. The flower visitation rate in both years was relatively high, although the total visit frequency decreased significantly in 2004. The control flowers without any treatment produced significantly fewer seed sets in 2004 than in 2002. In the past decade the seed production of this species may have partly decreased due to pollination by alien honeybees, however, we suggest that they might have acted as alternative pollinators ensuring seed production of S. przewalskii when native pollinators were unavailable. The main reason that this plant is endangered is probably the result of habitat destruction, but changes in land use, namely intensified agricultural practice and unfavorable animal husbandry have also contributed to its decline. We recommend that in-situ conservation, including the establishment of a protected area, is the best way to preserve this species effectively.     

Yield and Economic Performance of Organic and Conventional Cotton-Based Farming Systems – Results from a Field Trial in India

The debate on the relative benefits of conventional and organic farming systems has in recent time gained significant interest. So far, global agricultural development has focused on increased productivity rather than on a holistic natural resource management for food security. Thus, developing more sustainable farming practices on a large scale is of utmost importance. However, information concerning the performance of farming systems under organic and conventional management in tropical and subtropical regions is scarce. This study presents agronomic and economic data from the conversion phase (2007–2010) of a farming systems comparison trial on a Vertisol soil in Madhya Pradesh, central India. A cotton-soybean-wheat crop rotation under biodynamic, organic and conventional (with and without Bt cotton) management was investigated. We observed a significant yield gap between organic and conventional farming systems in the 1^st crop cycle (cycle 1: 2007–2008) for cotton (−29%) and wheat (−27%), whereas in the 2^nd crop cycle (cycle 2: 2009–2010) cotton and wheat yields were similar in all farming systems due to lower yields in the conventional systems. In contrast, organic soybean (a nitrogen fixing leguminous plant) yields were marginally lower than conventional yields (−1% in cycle 1, −11% in cycle 2). Averaged across all crops, conventional farming systems achieved significantly higher gross margins in cycle 1 (+29%), whereas in cycle 2 gross margins in organic farming systems were significantly higher (+25%) due to lower variable production costs but similar yields. Soybean gross margin was significantly higher in the organic system (+11%) across the four harvest years compared to the conventional systems. Our results suggest that organic soybean production is a viable option for smallholder farmers under the prevailing semi-arid conditions in India. Future research needs to elucidate the long-term productivity and profitability, particularly of cotton and wheat, and the ecological impact of the different farming systems.     

Impact of Cross-linking and Drying Method on Drug Delivery Performance of Casein–Pectin Microparticles

Pectin is a heteropolysaccharide which has been investigated for the development of colon-specific drug delivery systems. Polymers have been associated with pectin to reduce its aqueous solubility and improve the performance of drug delivery systems. Pectin–casein interaction is widely known in food research, but it has not been fully considered by pharmaceutical scientists. Thus, this study investigated the potential of casein–pectin microparticles as a drug delivery system and clarified the impact of cross-linking and drying methods on the in vitro release of indomethacin (IND) or acetaminophen (PCT) from microparticles. Microparticles were prepared by coacervation and dried by spray or spouted bed methods. Drug recovery, in vitro drug release, size, morphology, and the thermal and diffractometric properties of dried microparticles were determined. Spray-dried non-cross-linked microparticles were able to prolong IND release, and pectin was still degraded by pectinolytic enzymes. On the other hand, glutaraldehyde cross-linking prevented the enzymatic breakdown of pectin without improving IND release. Spouted bed drying reduced IND recovery from all microparticles when compared with spray drying, thus the successful spouted bed drying of microparticles depends on the chemical characteristics of both the drug and the polymer. Release data from PCT microparticles suggested that the microparticle formulation should be improved to bring about a more efficient delivery of water-soluble drugs. In conclusion, casein–pectin microparticles show great potential as a drug delivery system because casein reduces the water solubility of pectin. The drying method and cross-linking process had significant effects on the in vitro performance of these microparticles.     

The Tiotropium Safety and Performance in Respimat? (TIOSPIR?) Trial: Spirometry Outcomes

Background

Tiotropium Safety and Performance in Respimat® (TIOSPIR®) compared the safety and efficacy of tiotropium Respimat® and tiotropium HandiHaler® in patients with chronic obstructive pulmonary disease (COPD). A prespecified spirometry substudy compared the lung function efficacy between treatment groups.

Methods

TIOSPIR® was a large-scale, long-term (2.3-year), event-driven, randomized, double-blind, parallel-group trial of 17,135 patients with COPD. In the spirometry substudy, trough forced expiratory volume in 1 second (FEV₁) and forced vital capacity (FVC) were measured at baseline and every 24 weeks for the duration of the trial.

Results

The substudy included 1370 patients who received once-daily tiotropium Respimat® 5 μg (n = 461), 2.5 μg (n = 464), or tiotropium HandiHaler® 18 μg (n = 445). Adjusted mean trough FEV₁ (average 24–120 weeks) was 1.285, 1.258, and 1.295 L in the Respimat® 5 μg, 2.5 μg, and HandiHaler® 18 μg groups (difference versus HandiHaler® [95 % CI]: −10 [−38, 18] mL for Respimat® 5 μg and, −37 [−65, −9] mL for Respimat® 2.5 μg); achieving noninferiority to tiotropium HandiHaler® 18 μg for tiotropium Respimat® 5 but not for 2.5 μg (prespecified analysis). Adjusted mean trough FVC was 2.590, 2.544, and 2.593 L in the Respimat® 5 μg, 2.5 μg, and HandiHaler® 18 μg groups. The rates of FEV₁ decline over 24 to 120 weeks were similar for the three treatment arms (26, 40, and 34 mL/year for the tiotropium Respimat® 5-μg, 2.5-μg, and HandiHaler® 18-μg groups). The rate of FEV₁ decline in GOLD I + II patients was greater than in GOLD III + IV patients (46 vs. 23 mL/year); as well as in current versus ex-smokers, in patients receiving combination therapies at baseline versus not, and in those experiencing an exacerbation during the study versus not.

Conclusions

The TIOSPIR® spirometry substudy showed that tiotropium Respimat® 5 μg was noninferior to tiotropium HandiHaler® 18 μg for trough FEV₁, but Respimat® 2.5 μg was not. Tiotropium Respimat® 5 μg provides similar bronchodilator efficacy to tiotropium HandiHaler® 18 μg with comparable rates of FEV₁ decline. The rate of FEV₁ decline varied based on disease severity, with a steeper rate of decline observed in patients with moderate airway obstruction.

Trial registration

{"type":"clinical-trial","attrs":{"text":"NCT01126437","term_id":"NCT01126437"}}NCT01126437.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0269-4) contains supplementary material, which is available to authorized users.     

Performance of serum-supplemented and serum-free media in IFNγ Elispot Assays for human T cells

The choice of serum for supplementation of media for T cell assays and in particular, Elispot has been a major challenge for assay performance, standardization, optimization, and reproducibility. The Assay Working Group of the Cancer Vaccine Consortium (CVC-CRI) has recently identified the choice of serum to be the leading cause for variability and suboptimal performance in large international Elispot proficiency panels. Therefore, a serum task force was initiated to compare the performance of commercially available serum-free media to laboratories’ own medium/serum combinations. The objective of this project was to investigate whether a serum-free medium exists that performs as well as lab-own serum/media combinations with regard to antigen-specific responses and background reactivity in Elispot. In this way, a straightforward solution could be provided to address the serum challenge. Eleven laboratories tested peripheral blood mononuclear cells (PBMC) from four donors for their reactivity against two peptide pools, following their own Standard Operating Procedure (SOP). Each laboratory performed five simultaneous experiments with the same SOP, the only difference between the experiments was the medium used. The five media were lab-own serum-supplemented medium, AIM-V, CTL, Optmizer, and X-Vivo. The serum task force results demonstrate compellingly that serum-free media perform as well as qualified medium/serum combinations, independent of the applied SOP. Recovery and viability of cells are largely unaffected by serum-free conditions even after overnight resting. Furthermore, one serum-free medium was identified that appears to enhance antigen-specific IFNγ-secretion.     

Supplementation with α-Lipoic Acid,CoQ10, and Vitamin E Augments Running Performance and Mitochondrial Function in Female Mice

Antioxidant supplements are widely consumed by the general public; however, their effects of on exercise performance are controversial. The aim of this study was to examine the effects of an antioxidant cocktail (α-lipoic acid, vitamin E and coenzyme Q10) on exercise performance, muscle function and training adaptations in mice. C57Bl/J6 mice were placed on antioxidant supplement or placebo-control diets (n = 36/group) and divided into trained (8 wks treadmill running) (n = 12/group) and untrained groups (n = 24/group). Antioxidant supplementation had no effect on the running performance of trained mice nor did it affect training adaptations; however, untrained female mice that received antioxidants performed significantly better than placebo-control mice (p ≤ 0.05). Furthermore, antioxidant-supplemented females (untrained) showed elevated respiratory capacity in freshly excised muscle fibers (quadriceps femoris) (p ≤ 0.05), reduced oxidative damage to muscle proteins (p ≤ 0.05), and increased expression of mitochondrial proteins (p ≤ 0.05) compared to placebo-controls. These changes were attributed to increased expression of proliferator-activated receptor gamma coactivator 1α (PGC-1α) (p ≤ 0.05) via activation of AMP-activated protein kinase (AMPK) (p ≤ 0.05) by antioxidant supplementation. Overall, these results indicate that this antioxidant supplement exerts gender specific effects; augmenting performance and mitochondrial function in untrained females, but does not attenuate training adaptations.     

Receipt of Glucose Testing and Performance of Two US Diabetes Screening Guidelines, 2007–2012

Background

Screening guidelines are used to help identify prediabetes and diabetes before implementing evidence-based prevention and treatment interventions. We examined screening practices benchmarking against two US guidelines, and the capacity of each guideline to identify dysglycemia.

Methods

Using 2007–2012 National Health and Nutrition Examination Surveys, we analyzed nationally-representative, cross-sectional data from 5,813 fasting non-pregnant adults aged ≥20 years without self-reported diabetes. We examined proportions of adults eligible for diagnostic glucose testing and those who self-reported receiving testing in the past three years, as recommended by the American Diabetes Association (ADA) and the US Preventive Services Task Force (USPSTF-2008) guidelines. For each screening guideline, we also assessed sensitivity, specificity, and positive (PPV) and negative predictive values in identifying dysglycemia (defined as fasting plasma glucose ≥100 mg/dl or hemoglobin A1c ≥5.7%).

Results

In 2007–2012, 73.0% and 23.7% of US adults without diagnosed diabetes met ADA and USPSTF-2008 criteria for screening, respectively; and 91.5% had at least one major risk factor for diabetes. Of those ADA- or USPSTF-eligible adults, about 51% reported being tested within the past three years. Eligible individuals not tested were more likely to be lower educated, poorer, uninsured, or have no usual place of care compared to tested eligible adults. Among adults with ≥1 major risk factor, 45.7% reported being tested, and dysglycemia yields (i.e., PPV) ranged from 45.8% (high-risk ethnicity) to 72.6% (self-reported prediabetes). ADA criteria and having any risk factor were more sensitive than the USPSTF-2008 guideline (88.8–97.7% vs. 31.0%) but less specific (13.5–39.7% vs. 82.1%) in recommending glucose testing, resulting in lower PPVs (47.7–54.4% vs. 58.4%).

Conclusion

Diverging recommendations and variable performance of different guidelines may be impeding national diabetes prevention and treatment efforts. Efforts to align screening recommendations may result in earlier identification of adults at high risk for prediabetes and diabetes.     

The Effects of Suction and Pin/Lock Suspension Systems on Transtibial Amputees’ Gait Performance

Background

The suction sockets that are commonly prescribed for transtibial amputees are believed to provide a better suspension than the pin/lock systems. Nevertheless, their effect on amputees’ gait performance has not yet been fully investigated. The main intention of this study was to understand the potential effects of the Seal-in (suction) and the Dermo (pin/lock) suspension systems on amputees’ gait performance.

Methodology/Principal Findings

Ten unilateral transtibial amputees participated in this prospective study, and two prostheses were fabricated for each of them. A three-dimensional motion analysis system was used to evaluate the temporal-spatial, kinematics and kinetics variables during normal walking. We also asked the participants to complete some part of Prosthesis Evaluation Questionnaire (PEQ) regarding their satisfaction and problems with both systems. The results revealed that there was more symmetry in temporal-spatial parameters between the prosthetic and sound limbs using the suction system. However, the difference between two systems was not significant (p<0.05). Evaluation of kinetic data and the subjects’ feedback showed that the participants had more confidence using the suction socket and the sockets were more fit for walking. Nevertheless, the participants had more complaints with this system due to the difficulty in donning and doffing.

Conclusion

It can be concluded that even though the suction socket could create better suspension, fit, and gait performance, overall satisfaction was higher with the pin/lock system due to easy donning and doffing of the prosthesis.

Trial Registration

irct.ir IRCT2014012816395N1     

Fabrication and In Vitro/In Vivo Performance of Mucoadhesive Electrospun Nanofiber Mats Containing α-Mangostin

This study aimed to fabricate mucoadhesive electrospun nanofiber mats containing α-mangostin for the maintenance of oral hygiene and reduction of the bacterial growth that causes dental caries. Synthesized thiolated chitosan (CS-SH) blended with polyvinyl alcohol (PVA) was selected as the mucoadhesive polymer. α-Mangostin was incorporated into the CS-SH/PVA solution and electrospun to obtain nanofiber mats. Scanning electron microscopy, differential scanning calorimetry, X-ray diffraction, and tensile strength testing were used to characterize the mats. The swelling degree and mucoadhesion were also determined. The nanofiber mats were further evaluated regarding their α-mangostin content, in vitro α-mangostin release, antibacterial activity, cytotoxicity, in vivo performance, and stability. The results indicated that the mats were in the nanometer range. The α-mangostin was well incorporated into the mats, with an amorphous form. The mats showed suitable tensile strength, swelling, and mucoadhesive properties. The loading capacity increased when the initial amount of α-mangostin was increased. Rapid release of α-mangostin from the mats was achieved. Additionally, a fast bacterial killing rate occurred at the lowest concentration of nanofiber mats when α-mangostin was added to the mats. The mats were less cytotoxic after use for 72 h. Moreover, in vivo testing indicated that the mats could reduce the number of oral bacteria, with a good mouth feel. The mats maintained the amount of α-mangostin for 6 months. The results suggest that α-mangostin-loaded mucoadhesive electrospun nanofiber mats may be a promising material for oral care and the prevention of dental caries.KEY WORDS: dental caries, mucoadhesive property, nanofibers, thiolated chitosan, α-mangostin     

Performance and responses to competition in two congeneric annual species: does seed heteromorphism matter?

Variations in seed characteristics observed in heteromorphic species may affect various stages of their life cycles, e.g. seed dormancy, germination characteristics or even adult plant performance. Highly specialised seed morphs – described as colonisers and maintainers – exhibit a trade‐off between colonisation capacity and competitive traits. The performance of distinct seed morph progeny under competitive conditions, and especially in multi‐species arrangements, had previously not been given much attention. In this study, we compared performance and response to competition among distinct seed morph progenies in two congeneric, co‐occurring species: the invasive Bidens frondosa and the non‐invasive Bidens tripartita. We hypothesised that maintainer seed morphs of both species would perform better under increased plant densities and within inter‐morphic mixtures, while coloniser morphs would show stronger responses to increased densities and perform relatively poorly in inter‐morphic mixtures. We conducted a growth trial and a greenhouse experiment, which revealed that seed morph progeny differed significantly in plant height when grown without competition, while under competitive conditions such differences became less apparent. The observed pattern was more strongly pronounced in B. frondosa, which showed a general predominance in stature and biomass over its non‐invasive congener. Although seed morphs performed equally well under competitive conditions, increased plant height and more rapid germination can favour the maintainer seed morph on sites where vegetation is already present.