Application of Plant Oils as Functional Additives in Edible Films and Coatings for Food Packaging: A Review

Increasing environmental concerns over using petroleum-based packaging materials in the food industry have encouraged researchers to produce edible food packaging materials from renewable sources. Biopolymer-based edible films and coatings can be implemented as bio-based packaging materials for prolonging the shelf life of food products. However, poor mechanical characteristics and high permeability for water vapor limit their practical applications. In this regard, plant oils (POs) as natural additives have a high potential to overcome certain shortcomings related to the functionality of edible packaging materials. In this paper, a summary of the effects of Pos as natural additives on different properties of edible films and coatings is presented. Moreover, the application of edible films and coatings containing POs for the preservation of different food products is also discussed. It has been found that incorporation of POs could result in improvements in packaging's barrier, antioxidant, and antimicrobial properties. Furthermore, the incorporation of POs could significantly improve the performance of edible packaging materials in preserving the quality attributes of various food products. Overall, the current review highlights the potential of POs as natural additives for application in edible food packaging materials.

Ophthalmic findings associated with Australian tick paralysis (holocyclotoxicity) in hospitalized domestic dogs and cats

OBJECTIVE

To describe ophthalmic findings in hospitalized canine and feline patients with tick paralysis (TP) and investigate possible predisposing factors.

ANIMALS STUDIED

Forty-seven dogs and 28 cats hospitalized with TP assessed with an ophthalmic examination performed by an ABVO resident.

METHODS

Dogs and cats were hospitalized with TP from October 2021 to January 2022 and had an ophthalmic examination performed by an ABVO resident. Patient signalment data, information regarding tick number and location, hospitalization duration, medications used, and patient paralysis grades were recorded. Statistical analysis was performed to correlate findings.

RESULTS

Corneal ulcers developed in up to 34.8% of dogs and up to 42.9% of cats hospitalized with TP. An absent palpebral reflex ipsilaterally increased the odds of a concurrent corneal ulcer being present by 14.7× in dogs and 20.1× in cats (p < .0001). Palpebral reflexes were absent in 38.3% of dogs and 35.7% of cats hospitalized with TP and were correlated with more severe gait paralysis (p = .01) and respiratory paralysis (p = .005) in dogs, and respiratory paralysis in cats (p = .041). STT-1 findings <10 mm/min were present in 27.7% of dogs and 57.1% of cats examined and were associated with increasing gait paralysis (p = .017) and respiratory paralysis (p = .007) in dogs, and increasing gait paralysis in cats (p = .017).

CONCLUSIONS

Simple corneal ulcers, loss of a complete palpebral reflex, and reduced STT-1 scores frequently occurred in dogs and cats hospitalized for TP. The frequency of these findings increased as the degree of patient paralysis increased.

Feline distichiasis treated with cryoepilation: A retrospective study of 15 cats (27 eyes)

OBJECTIVE

To describe the clinical features of cats diagnosed with distichiasis and report on the outcomes following cryoepilation.

ANIMALS STUDIED

Fifteen cats (27 eyes).

PROCEDURES

Medical records of domestic cats with distichiasis that underwent a double freeze-thaw cycle with a -80°C cryoprobe applied to the palpebral conjunctiva, with hair then epilated were retrospectively studied. The patient signalment, distichiae locations, concurrent ocular diseases, recurrences, complications, and outcomes were recorded.

RESULTS

The mean (std dev) age at the time of diagnosis and treatment was 2.2 years (2.8 years). All (15/15) cats were of the domestic shorthair (DSH) breed. Concurrent ocular findings at the initial examination were observed in 17/27 (63%) eyes, with upper lateral eyelid hypoplasia the most prevalent, present in 9/27 (33.3%) eyes. Recurrence of distichiae occurred in 8/27 (29.6%) eyes. The clinical presentation in the instances of recurrence was judged as asymptomatic and not of a clinical concern in 3/27 (11.1%) eyes, with a second procedure deemed necessary to alleviate symptoms in 5/27 (18.5%) eyes. All eyes treated with a second procedure had no recurrence of distichiae or symptoms. Complications following cryoepilation occurred in 4/27 (14.8%) eyes, with two cats developing bilateral entropion post-procedure.

CONCLUSIONS

Treatment of distichiasis in cats utilizing cryoepilation was effective at alleviating symptoms, though some cats needed a second procedure. The development of post-procedural entropion was seen occasionally.

Retrospective assessment of ophthalmic disease development in domestic dogs and cats when hospitalised with tick paralysis caused by Ixodes holocyclus

OBJECTIVE

To investigate the incidence and predisposing factors leading to the development of corneal ulcers and the loss of a palpebral reflex in hospitalised canine and feline patients with tick paralysis (TP).

ANIMALS STUDIED

A total of 102 dogs and 100 cats retrospectively were assessed from previously hospitalised patients.

METHODS

A retrospective cohort study was performed on 102 different canine and 100 different feline patients who were hospitalised for TP from October 2020-January 2022. Patient data were collected, and logistic regression was conducted to determine factors affecting the palpebral reflex and the development of corneal ulcers.

RESULTS

Corneal ulcers occurred in 23/102 (22.5%) dogs during hospitalisation and were strongly associated with an incomplete palpebral reflex ipsilaterally during hospitalisation (P < 0.001), hospitalisation ≥3 days (P = 0.004), mechanical ventilation ≥3 days (P = 0.015) or a tick location cranial to C1 (P = 0.003). An incomplete palpebral reflex during hospitalisation was observed in 29/102 (28.4%) dogs and was significantly associated with decreasing patient weight (P = 0.018), increasing days hospitalised (P = 0.001), having a tick found cranial to C1 (P = 0.004), highest recorded GP grade (P = 0.01), highest recorded RP grade (P = 0.005), use of amoxycillin-clavulanic acid during hospitalisation (P = 0.002) and use of piperacillin/tazobactam during hospitalisation (P = 0.003). There was a significant association between the loss of a complete palpebral reflex and mortality during hospitalisation in dogs (OR = 4.5, P = 0.029). Corneal ulcers occurred in 10/100 (10.0%) cats during hospitalisation, and was significantly more likely to occur to an eye if an incomplete palpebral reflex was observed ipsilaterally during hospitalisation (OR = 20.1, P < 0.0001) and with increasing patient age (P = 0.019). The absence of a complete palpebral reflex during hospitalisation was observed in 18/10 (18.0%) cats and was significantly associated with increasing days hospitalised (P = 0.034). There was no significant association between the loss of a complete palpebral reflex and mortality during hospitalisation in cats.

CONCLUSIONS

The frequency of corneal ulcers and loss of palpebral reflexes were significant in dogs and cats hospitalised by TP, with many factors contributing to the risk of these developing.

Effect of Immersion Time of Chicken Breast in Potato Starch Coating Containing Lysine on PhIP Levels

This study investigated the effect of immersion time of chicken breasts in potato starch (PS) coating containing amino acids (AAs) on the formation of 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP) and to evaluate a possible mechanism to inhibit the formation of PhIP in chicken breasts during frying. The chicken breasts with standardized dimensions were dipped in the potato starch (PS) coating solution containing 0.25% w/v lysine (Lys) for different times (15 min, 30 min, 1 h, 3 h, and 6 h). After drying the coating on the chickens, samples were fried at 195 °C for 7.5 min on each side. Results showed that the immersion time does not significantly decrease (p < 0.05) the PhIP level, suggesting that 15 min immersion time is enough for PhIP reduction compared to the control chicken samples (without coating). Phenylacetaldehyde (PheAce) was increased in chicken breast coated with PS-0.25% Lys after frying, suggesting that there should be another pathway to prevent the formation of PhIP by the addition of PS-0.25% Lys. Volatile compound analysis also confirmed this and showed increases in many aroma compounds in the coated chicken. Moreover, no significant differences (p < 0.05) were shown between the cooking loss percentage, color parameters, texture profile, and tenderness of chicken with the PS-0.25% coating and chicken without coating.

Effect of potato starch coating containing selected amino acids to prevent the formation of PhIP in pan-fried chicken breast

The effects of potato starch (PS) coating containing amino acids (AAs) on the formation of 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP) in chicken breasts were evaluated. PhIP is classified as a Group 2B carcinogen by the International Agency for Research on Cancer (IARC). The 5% (w/w) gelatinized PS coating solution was incorporated with tryptophan (Trp) or lysine (Lys) at 0.25%, 0.5%, and 0.75% (w/w of the coating solution) concentrations. Chicken breast cuts with the same dimensions (5 × 2 × 1.5 cm) were dipped in the PS coating solution for 15 min before frying. After frying the chicken at 195°C for 7.5 min on each side, PhIP levels, color, cooking loss, tenderness, and texture profile assay were evaluated. The average PhIP concentration was decreased from 92.62 ng/g for the control chicken breast without coating to 6.30 ng/g (0.25% Lys), 6.76 ng/g (0.5% Lys), and 11.98 ng/g (0.75% Lys), accounting for an 89%-92% reduction in PhIP levels compared to the controls. However, dipping in Trp-containing PS coating had a significantly lower (p < 0.05) PhIP reduction effect (34%-67%). There was no significant difference in cooking loss percentage, tenderness, texture profile parameters, and color parameters of PS-coated chicken. Triangle test results showed that consumers did not detect a significant difference in the PS-coated chicken breasts (p < 0.001). Overall, this study suggests that the application of PS-based coatings incorporated with AAs on chicken breast reduces the PhIP formation.

Interaction of 2-dodecylcyclobutanone (2-DCB) and internal standard in irradiated chicken jerkies and pig ears in solid-phase microextraction (SPME)-coupled gas chromatography-mass spectrometry (GC-MS) analysis

The radiolysis of palmitic acid in chicken jerky (CJ) and pig ears (PE) can form 2-dodecylcyclobutanone (2-DCB). A solid-phase micro extraction-coupled GC-MS technique can be used for quantitative analysis of 2-DCB with the adequate use of an internal standard (IS). The objectives of this study are to: 1) investigate the IS and 2-DCB interactions as a function of IS concentration and irradiation dose; 2) elucidate the effects of bound 2-DCB; 3) use electron paramagnetic resonance spectroscopy to complement 2-DCB measurements. The measurement of 2-DCB formed by irradiation was significantly (P < 0.05) affected by the palmitic acid content and IS concentration. The amount of 2-DCB measured in irradiated (10 kGy) CJ and PE increased 70% and 300%, respectively, when the IS concentration increased from 8 to 800 ppb. Our findings serve as a guide for the adequate use of IS for quantitative analysis of 2-DCB formed in irradiated meat matrixes.

Effect of whey protein isolate-based edible films containing amino acids on the PhIP level and physicochemical properties of pan-fried chicken breasts

This study was conducted to investigate the inhibitory effects of edible films containing amino acids (AAs) on the formation of 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP) in chicken breasts and to evaluate the physicochemical properties of the edible films. Heated whey protein isolate (HWPI) solution was made by heating 5 g whey protein isolate (WPI) solution at 90°C for 30 min in a water bath and subsequently mixed with 2.5 g glycine, and tryptophan (Trp) or lysine (Lys) at 0.25%, 0.5%, and 0.75% concentrations. Unheated whey protein isolate (UHWPI)-based casting solution was prepared with the same method but without heating of WPI solution. Chicken breasts were cut at the same weights and were covered with the prepared edible films. For edible films, total soluble matter (TSM%), color (calorimeter), radical scavenging activity (DPPH), and Fourier transform infrared spectroscopy (FTIR) were conducted. For chicken breasts, PhIP level, color before and after frying (calorimeter), cooking loss percentage (weigh loss before after frying), and tenderness (texture analyzer) were evaluated. The average PhIP level decreased from 78.47 ppb to 6.69-8.31 ppb for chicken covered with Lys-containing HWPI edible films, and to 25.82-46.80 ppb for chicken covered with Trp-containing ones. For chicken covered with UHWPI edible films, the PhIP decreased 28.4-56.04 ppb for Trp-containing ones and 19.67-40.32 ppb for Lys-containing ones. Moreover, chicken breasts covered with HWPI edible films had lower cooking loss and improved tenderness compared to the chicken breasts with no edible film. This study provides a new approach to decrease the PhIP levels in fried chicken breast.

Multi-phase equation of state of ultrapure hafnium to 120 GPa

Hafnium (Hf) is an industrially important material due to its large neutron absorption cross-section and its high corrosion resistance. When subjected to high pressure, Hf phase transforms from its hexagonal close packed α-Hf phase to the hexagonal ω-Hf phase. Upon further compression, ω-Hf phase transforms to the body centered cubic β-Hf phase. In this study, the high pressure phase transformations of Hf are studied by compressing and decompressing a well-characterized Hf sample in diamond anvil cells up to 120 GPa while collecting x-ray diffraction data. The phase transformations of Hf were compared in both a He pressure transmitting medium (PTM) and no PTM over several experiments. It was found that the α-Hf to ω-Hf phase transition occurs at a higher pressure during compression and lower pressure during decompression with a helium (He) PTM compared to using no PTM. There was little difference in the ω-Hf to β-Hf phase transition pressure between the He PTM and no PTM. The equation of state was fit for all three phases of Hf and under both PTM and no-PTM.

Identification of the characteristics of occlusive myocardial infarction: are there any tell-tale signs?

Introduction

Treatment urgency of myocardial infarction (MI) is currently stratified by ST elevation (STEMI) or lack of ST elevation (NSTEMI) on the electrocardiogram. This categorisation arose from the theory that ST elevation indicated total acute coronary artery occlusion (1). However, one-quarter of all NSTEMI have acute occlusion, have a higher mortality and are potentially missed by this strategy (2).

Purpose

The study purpose is to identify clinical features that could help distinguish an occlusive MI from non-occlusive MI.

Methods

The prospectively British Cardiovascular Intervention Society (BCIS) data set was collected from patients undergoing primary cutaneous intervention (dataset) was analysed from the years 2015 to 2019. Data collected included presentation characteristics, co-morbidities, treatments and outcomes. We further undertook latent class analysis, to determine whether distinct patterns of presentation and history are associated with acutely occluded NSTEMI. This methodology proceeds through segmentation of a dataset into clusters (“classes”) based on case similarities for the set of variables or “indicators” of interest; the classes are then statistically analysed to evaluate the differences between them.

Results

A total of 2025 patients underwent percutaneous coronary intervention (PCI) between 2015 and 2019. Of these, 1412 underwent PCI for MI, 510 had a STEMI, and 263 had occlusive MI on angiogram. STEMI patients tended to be younger (66 vs 67; p=0.045), in shock (6.1% vs 1.9%; p&lt;0.001), have cardiac arrest (5.7% vs 1.2%; p&lt;0.001), less co-morbidities, increased left ventricular ejection fraction (LVEF) (&lt;30% 11.8% vs 4.7%; p&lt;0.001, increased short-term mortality (3.5% vs 0.7%; p&lt;0.001) and increased emergency PCI (55.9% vs 6.9%; p&lt;0.001) and thrombolysis (32.7% vs 2.5%; p&lt;0.001),. Occlusive MI patients tended to have ST elevation (63.5% vs 29.9%: p&lt;0.001), cardiogenic shock (9.1% vs 2.1%; p&lt;0.001) cardiac arrest (5.3% vs 2.3%; p=0.007), less co-morbidities but no difference in cerebrovascular disease, increased acute mortality (4.2% vs 1.1%; p&lt;0.001) severe LVEF (11.8% vs 6.2%; p&lt;0.001) and increased emergency PCI (70.3% vs 14.1%; p&lt;0.001), With latent class analysis, while clusters of similar patients are observed in the dataset, we determined that the variables captured by BCIS do not usefully indicate an acutely occluded MI compared to non-occlusive MI (Figure 1).

Conclusion

Features between occlusive MI and STEMI are broadly very similar. However, unlike STEMI/NSTEMI, there was no difference in age and risk of cerebrovascular disease in the occlusive MI/non-occlusive MI group. This could indicate occlusion MI occurs in higher numbers in elderly and frail patients and may be frequently missed, possibly from greater collateralisation. There is no reliable characteristic for identifying occlusive between non-occlusive MI. Improved methods are needed for the identification of occlusive MI patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): A project supported by the European Union's INTERREG VA Programme, managed by the Special EU Programmes Body (SEUPB). The funders of this project had no input in designing, implementation or writing of this review. Step 1 of latent class analysis

Effects of guanidinoacetic acid supplementation on nitrogen retention and methionine flux in cattle

Creatine stores high-energy phosphate bonds in muscle and is synthesized in the liver through methylation of guanidinoacetic acid (GAA). Supplementation of GAA may therefore increase methyl group requirements, and this may affect methyl group utilization. Our experiment evaluated the metabolic responses of growing cattle to postruminal supplementation of GAA, in a model where methionine (Met) was deficient, with and without Met supplementation. Seven ruminally cannulated Holstein steers (161 kg initial body weight [BW]) were limit-fed a soybean hull-based diet (2.7 kg/d dry matter) and received continuous abomasal infusions of an essential amino acid (AA) mixture devoid of Met to ensure that no AA besides Met limited animal performance. To provide energy without increasing the microbial protein supply, all steers received ruminal infusions of 200 g/d acetic acid, 200 g/d propionic acid, and 50 g/d butyric acid, as well as abomasal infusions of 300 g/d glucose. Treatments, provided abomasally, were arranged as a 2 × 3 factorial in a split-plot design, and included 0 or 6 g/d of l-Met and 0, 7.5, and 15 g/d of GAA. The experiment included six 10-d periods. Whole body Met flux was measured using continuous jugular infusion of 1-13C-l-Met and methyl-2H3-l-Met. Nitrogen retention was elevated by Met supplementation (P < 0.01). Supplementation with GAA tended to increase N retention when it was supplemented along with Met, but not when it was supplemented without Met. Supplementing GAA linearly increased plasma concentrations of GAA and creatine (P < 0.001), but treatments did not affect urinary excretion of GAA, creatine, or creatinine. Supplementation with Met decreased plasma homocysteine (P < 0.01). Supplementation of GAA tended (P = 0.10) to increase plasma homocysteine when no Met was supplemented, but not when 6 g/d Met was provided. Protein synthesis and protein degradation were both increased by GAA supplementation when no Met was supplemented, but decreased by GAA supplementation when 6 g/d Met were provided. Loss of Met through transsulfuration was increased by Met supplementation, whereas synthesis of Met from remethylation of homocysteine was decreased by Met supplementation. No differences in transmethylation, transsulfuration, or remethylation reactions were observed in response to GAA supplementation. The administration of GAA, when methyl groups are not limiting, has the potential to improve lean tissue deposition and cattle growth.

An analysis of cellulose- and dextrose-based radicals in sweet potatoes as irradiation markers

Dried sweet potatoes (SPs) are often irradiated for improved safety and shelf life. Formation of irradiation-derived radicals was analyzed using electron paramagnetic resonance (EPR) spectroscopy. These irradiation-specific radicals can be used to characterize the irradiation history of dry plant-based foods containing cellulose and sugars. The signal characteristics (intensity and peak shape) were evaluated at different sample locations (skin and flesh), as a function of sample preparation method (grinding, sieving, and pelletizing). The signal intensity was quantified using a double integration method of the peaks based on the area under the curve. The sieving caused ca. 50% decrease in total signal intensity as compared to nonsieved samples due to loss of cellulose-based radicals. The flesh of irradiated SP showed complex EPR spectra with multiple satellite peaks of cellulose radicals (333.5 and 338.8 mT) and split peak of dextrose radicals (337.4 mT); while skin spectra were distinctive of cellulose radicals. In this study, we demonstrated the effects of sample composition and preparation method on formation and analysis of irradiation-specific radicals based on EPR. PRACTICAL APPLICATION: In the last decade or so, there have been health concerns related to the consumption of irradiated pet food products. Electron paramagnetic resonance spectroscopy can be used to analyze the irradiation history of dry products containing cellulose and sugar, such as the popular dog treat dried sweet potatoes, to ensure the products were irradiated within safe limits. This work demonstrates that the formation of irradiation-specific radicals is affected by the sample location (skin and flesh) and moisture content.

Solid-phase micro extraction of food irradiation marker 2-dodecylcyclobutanone (2-DCB) from chicken jerky treated with glycerol

The food irradiation marker, 2-dodecylcyclobutanone (2-DCB), assayed by SPME provides a fast and simple method to estimate the irradiation history of fat-containing food products. The SPME conditions were optimized to maximize the extraction of 2-DCB from chicken jerky treats (CJT) irradiated at low (5 kGy) and high (50 kGy) doses. The extracted 2-DCB was measured using GC-MS in selected ion mode (m/z 98, and 112). Water dilution (1:5) was needed to mobilize 2-DCB and allow partition to the headspace form the CJT matrix. Increasing the incubation temperature to 80 °C resulted in higher response. Spiking control jerky samples with 2-DCB from 10 to 150 ng/g CJT compared with spiking water revealed a significant food matrix effect. This method provides a fast, simple, and environmental friendly alternative for the existing solvent extraction methods.

Mapping Quantitative Trait Loci for Resistance to Fall Armyworm (Lepidoptera: Noctuidae) Leaf-Feeding Damage in Maize Inbred Mp705

The fall armyworm, Spodoptera frugiperda (J. E. Smith), is an agronomically important pest that severely limits maize (Zea mays (Linnaeus) [Poales: Poaceae]) production. This migrant insect devastates maize plants in many countries threatening the livelihood of millions. Quantitative trait loci (QTL) were mapped to identify chromosomal regions that control resistance to fall armyworm leaf-feeding and to identify molecular markers linked to the target loci for use in marker-assisted selection (MAS). A bi-parental mapping population, comprising 243 F2:3 families from the cross Mp705 (resistant) × Mp719 (susceptible), was evaluated for fall armyworm leaf-feeding damage under artificial infestation over 3 yr. A linkage map comprised of 1,276 single-nucleotide polymorphism and simple sequence repeat molecular markers was constructed. Quantitative trait loci analyses identified two major QTL in bins 4.06 and 9.03 that when combined, explained 35.7% of the phenotypic variance over all environments. Mp705 was responsible for the leaf-feeding damage reducing alleles for both large effect QTL and most of the small effect QTL identified in this study. The QTL identified in bin 9.03 co-locates with a previously identified QTL that controls resistance to leaf-feeding damage in maize by fall armyworm and other lepidopteran insects. The QTL in bin 4.06 is a new source of resistance identified in this study. Beneficial alleles derived from Mp705 for the application of an integrated QTL-MAS approach could accelerate breeding efforts to minimize fall armyworm leaf-feeding in maize.

Amino acids effects on heterocyclic amines formation and physicochemical properties in pan-fried beef patties

The effects of surface application of amino acids on the formation of heterocyclic amines (HCAs) and meat quality properties were evaluated in pan-fried beef patties (230 °C/15 min). Tryptophan, lysine, leucine, and proline at three concentrations, 0.05%, 0.20%, and 0.50% (w/w), were tested. The meat crusts were analyzed for HCA content using liquid chromatography-tandem mass spectrometry. Results showed that surface application of all tested amino acids significantly reduced total HCA content (P < 0.05), and the interaction of amino acid type and concentration significantly affected (P < 0.05) both individual and total HCA formation. Tryptophan at 0.50% reduced total HCAs the most (0.92 ng/g, 93% inhibition), followed by 0.50% lysine (1.94 ng/g, 84% inhibition), while leucine (3.95 ng/g, 64% inhibition) and proline (4.71 ng/g, 56% inhibition) were less effective at 0.50%. In addition, applying amino acids to meat surface significantly influenced (P < 0.05) pH and surface color change of beef crusts; particularly, lysine at 0.20% and 0.50% increased pH and a^* (redness) but reduced b^* (yellowness), while tryptophan and leucine at 0.50% increased L^* (whiteness). No significant effect was observed on cooking loss. Adding amino acids at 0.50% affected (P < 0.05) formation of aldehydes and pyrazines (as the key flavor compounds of fried beef). Overall, the results of this study suggested that adding amino acids to ground beef patties could effectively mitigate mutagenic HCA formation during cooking.

Variations in the aftercare of facial wounds: a survey of maxillofacial clinicians

Good aftercare of traumatic wounds reduces the risk of infection and improves functional and aesthetic outcomes. Inconsistencies in the instructions given by oral and maxillofacial (OMF) surgeons to patients with facial lacerations have previously been noted. We therefore sent anonymous online surveys to OMF clinicians in the United Kingdom to investigate the extent of the variation in aftercare advice given to patients who have had traumatic lacerations of the skin of the head and neck. Respondents were asked about their current practice, including instructions on how to clean wounds, the provision of cleaning materials, use of topical dressings, and advice regarding dry time; also the number of days before the removal of sutures, and specialist review of facial wounds. A total of 63 responded. There was considerable variation within and between grades regarding the advice given. Advice varied and there was no consensus in any of the areas questioned. Robust evidence on the aftercare of traumatic lacerations is lacking. To develop practical guidelines for advice there is a need for further research in the area and further discussion about the aftercare of lacerations.

Smoked Sugar Improves Flavor Stability of Frozen Sliced Food Service Bacon

Aerobically packaged frozen bacon has significant challenges to flavor and odor properties as storage length advances. Naturally smoked sugar (NSS), a food ingredient made from applying hardwood smoke to liquid sugar, may possess antioxidant functionality that is beneficial in controlling lipid oxidation in bacon. Therefore, the objective of this study was to determine if NSS could be added directly to a bacon formulation to limit the rate of lipid oxidation in frozen, aerobically packaged bacon. Three replications of this experiment were conducted using 5 pork bellies per replication. Individual bellies were cut in half yielding an anterior and posterior section and then randomly assigned to a treatment combination with either the anterior or posterior section receiving the NSS treatment. Treatment brines consisted of a control (CON) brine or a brine with added NSS injected to retain 12% added solution. After injection, smoking, cooking, and slicing, bacon slices were frozen (–17.8 ± 2°C) and stored aerobically for 0, 40, 80, and 120 d for sensory and gas chromatography mass spectrometry (GCMS) analyses or 0, 20, 40, 60, 80, 100, and 120 d for thiobarbituric acid reactive substances (TBARS) analysis. There were significant (P < 0.01) Treatment × Day interactions for oxidized flavor intensity, TBARS, and hexanal concentration. Panelist oxidized flavor intensity scores, TBARS values, and hexanal content increased from d 0 to 120 (P < 0.01) for CON, whereas these measures in bacon manufactured with added NSS did not change (P > 0.16). Sensory ratings for saltiness, smoke intensity, and bacon flavor intensity were higher (P < 0.01) for the NSS treatment compared to CON. The ability of NSS to function as an effective antioxidant in frozen bacon was confirmed by the inhibition of lipid oxidation products and improved sensory panel scores over time.

Effects of transdermal flunixin meglumine on experimentally induced lameness in adult dairy cattle

Lameness is a common animal health condition with significant production and welfare implications. The transdermal formulation of flunixin meglumine is the only approved drug for pain control in cattle in the United States. Thirty adult dairy cows were enrolled in a study to determine the effect of transdermal flunixin on cattle with induced lameness. Cows were allocated to 1 of 3 treatment groups, with 10 cows per group: lameness and flunixin (L+F), lameness and placebo (L+P), or sham induction and placebo (S+P). An arthritis-synovitis was induced in the distal interphalangeal joint of the left hind lateral digit, using 20 mg of amphotericin B, 6 h before the application of treatment. Cows enrolled into the sham induction group had 4 mL of isotonic saline injected into the joint. Cows were dosed with transdermal flunixin at 3.33 mg/kg (1 mL/15 kg), or a placebo at 1 mL/15 kg, every 24 h for 3 d. The first treatment of flunixin or placebo was considered the start of the study, identified as time 0 h. Data were collected from all cows for 120 h following the initial treatment application. Outcome measures included plasma cortisol; substance P; visual lameness assessment; mechanical nociception threshold (MNT), presented as difference between left and right feet; infrared thermography (IRT), presented as difference between left and right feet; and gait analysis using a pressure mat. Cortisol concentrations were lower for the L+F group starting at 1.5 h after drug administration. Substance P levels showed no evidence for treatment differences among groups. Differences between the left hind MNT and right hind MNT were detected, with S+P having the lowest difference at -0.04 kilograms-force (kgf; 95% CI: -1.86 to 1.78 kgf), and L+P having the highest at -2.96 kgf (95% CI: 1.55 to 4.36 kgf). The L+F group was intermediate at -2.08 kgf (95% CI: 0.89 to 3.27 kgf). Similarly, when the difference between the maximum temperatures of the coronary band were examined via IRT, the L+P group had the highest difference at 1.64°C (95% CI: 1.02 to 2.26°C), with the L+F and S+P groups measuring 0.57°C (95% CI: 0.06 to 1.08°C) and 0.53°C (95% CI: -0.2 to 1.25°C) respectively. We found no evidence for differences among treatment groups when analyzing force, contact pressure, step impulse, or stride length. Based on differences in MNT, IRT, and cortisol, transdermal flunixin is an effective analgesic agent for induced lameness. Multiple doses of transdermal flunixin may be required to be clinically effective, based on MNT and IRT data. Further investigation of transdermal flunixin and its analgesic effects is warranted in naturally occurring lameness.

Pharmacokinetics of fentanyl citrate and norfentanyl in Holstein calves and effect of analytical performances on fentanyl parameter estimation

This study describes the pharmacokinetics of intravenously administered (i.v.) fentanyl citrate, and its primary metabolite norfentanyl in Holstein calves. Eight calves (58.6 ± 2.2 kg), aged 3-4 weeks, were administered fentanyl citrate at a single dose of 5.0 μg/kg i.v. Blood samples were collected from 0 to 24 hr. Plasma (nor)fentanyl concentrations were determined using liquid chromatography with mass spectrometry and a lower limit of quantification (LLOQ) of 0.03 ng/ml. To explore the effect of analytical performance on fentanyl parameter estimation, the noncompartmental pharmacokinetic analysis was then repeated with a hypothetical LLOQ value of 0.05 ng/ml. Terminal elimination half-life was estimated at 12.7 and 3.6 hr for fentanyl and norfentanyl, respectively. For fentanyl, systemic clearance was estimated at 2.0 L hr^-1  kg^-1 , volume of distribution at steady-state was 24.8 L/kg and extraction ratio was 0.42. At a hypothetical LLOQ of 0.05 ng/ml fentanyl half-life, volume of distribution at steady-state and clearance were, respectively, of 3.0 hr, 8.8 L/kg and 3.4 L kg^-1  hr^-1 . Fentanyl citrate administered i.v. at 5.0 μg/kg can reach levels associated with analgesia in other species. Pharmacokinetic parameters should be interpreted with respect to LLOQ, as lower limits can influence estimated parameters, such as elimination half-life or systemic clearance and have significant impact on dosage regimen selection in clinical practice.

Pharmacokinetics of multiple doses of transdermal flunixin meglumine in adult Holstein dairy cows

A transdermal formulation of the nonsteroidal anti-inflammatory drug, flunixin meglumine, has been approved in the United States and Canada for single-dose administration. Transdermal flunixin meglumine was administered to 10 adult Holstein cows in their second or third lactation at the label dose of 3.33 mg/kg every 24 hr for three total treatments. Plasma flunixin concentrations were determined using high-pressure liquid chromatography with mass spectroscopy (HPLC-MS). Pharmacokinetic analysis was completed on each individual animal with noncompartmental methods using computer software. The time to maximum drug concentration (Tmax) was 2.81 hr, and the maximum drug concentration was 1.08 μg/ml. The mean terminal half-life (T½) was determined to be 5.20 hr. Clearance per fraction absorbed (Cl/F) was calculated to be 0.294 L/hr kg^-1 , and volume of distribution of fraction (Vz/F) absorbed was 2.20 L/kg. The mean accumulation factor was 1.10 after three doses. This indicates changes in dosing may not be required when giving multiple doses of flunixin transdermal. Further work is required to investigate the clinical efficacy of transdermal flunixin after multiple daily doses.

Ab initio calculation of energy levels for phosphorus donors in silicon

The s manifold energy levels for phosphorus donors in silicon are important input parameters for the design and modeling of electronic devices on the nanoscale. In this paper we calculate these energy levels from first principles using density functional theory. The wavefunction of the donor electron's ground state is found to have a form that is similar to an atomic s orbital, with an effective Bohr radius of 1.8 nm. The corresponding binding energy of this state is found to be 41 meV, which is in good agreement with the currently accepted value of 45.59 meV. We also calculate the energies of the excited 1s(T ₂) and 1s(E) states, finding them to be 32 and 31 meV respectively.

ANI-1: an extensible neural network potential with DFT accuracy at force field computational cost

Deep learning is revolutionizing many areas of science and technology, especially image, text, and speech recognition. In this paper, we demonstrate how a deep neural network (NN) trained on quantum mechanical (QM) DFT calculations can learn an accurate and transferable potential for organic molecules. We introduce ANAKIN-ME (Accurate NeurAl networK engINe for Molecular Energies) or ANI for short. ANI is a new method designed with the intent of developing transferable neural network potentials that utilize a highly-modified version of the Behler and Parrinello symmetry functions to build single-atom atomic environment vectors (AEV) as a molecular representation. AEVs provide the ability to train neural networks to data that spans both configurational and conformational space, a feat not previously accomplished on this scale. We utilized ANI to build a potential called ANI-1, which was trained on a subset of the GDB databases with up to 8 heavy atoms in order to predict total energies for organic molecules containing four atom types: H, C, N, and O. To obtain an accelerated but physically relevant sampling of molecular potential surfaces, we also proposed a Normal Mode Sampling (NMS) method for generating molecular conformations. Through a series of case studies, we show that ANI-1 is chemically accurate compared to reference DFT calculations on much larger molecular systems (up to 54 atoms) than those included in the training data set.

The Association between the History of HIV Diagnosis and Oral Health

Unmet oral care needs are high among people living with human immunodeficiency virus (HIV)/AIDS (PLWH). Oral health care is of increasing importance as life expectancy is being prolonged extensively among PLWH. The benefit of oral health care in relation to time since HIV diagnosis has not previously been assessed. A retrospective multivariable analysis of the Special Project of National Significance Oral Health Initiative observational cohort study ( N = 2,178) was performed to estimate the odds ratios (ORs) of oral health outcomes comparing historically diagnosed subjects (>1 y since HIV diagnosis) to newly diagnosed subjects (≤1 y since HIV diagnosis). ORs were adjusted for age, study site, language, income, last dental care visit, and dental insurance. Historically diagnosed subjects were more likely to report oral problems than newly HIV-diagnosed subjects (OR, 2.10). Historically diagnosed subjects were more likely to require oral surgery (OR, 1.52), restorative treatment (OR, 1.35), endodontic treatment (OR, 1.63), and more than 10 oral clinic visits over the 24-mo study period (OR, 2.02). The crude cumulative 2-y risk of requiring prosthetic (risk difference [RD], 0.21) and endodontic (RD, 0.11) treatment was higher among historically than newly diagnosed subjects, despite no significance postadjustment. Furthermore, poor oral health outcomes were exacerbated among non-highly active antiretroviral therapy users. Summarizing, the authors found that historically diagnosed subjects were more likely to report oral problems and require dental procedures compared with newly diagnosed subjects, suggesting that oral health among PLWH declines over time since HIV diagnosis. Hence, newly diagnosed PLWH may benefit from the implementation of early oral interventions.

Comparison of urine specimen collection times and testing fractions for the detection of high-risk human papillomavirus and high-grade cervical precancer

BACKGROUND

Urine testing for high-risk human papillomavirus (HR-HPV) detection could provide a non-invasive, simple method for cervical cancer screening.

OBJECTIVES

We examined whether HR-HPV detection is affected by urine collection time, portion of urine stream, or urine fraction tested, and assessed the performance of HR-HPV testing in urine for detection of cervical intraepithelial neoplasia grade II or worse (CIN2+).

STUDY DESIGN

A total of 37 female colposcopy clinic attendees, ≥ 30 years, provided three urine samples: "first void" urine collected at home, and "initial stream" and "mid-stream" urine samples collected at the clinic later in the day. Self- and physician-collected brush specimens were obtained at the same clinic visit. Colposcopy was performed and directed biopsies obtained if clinically indicated. For each urine sample, HR-HPV DNA testing was conducted for unfractionated, pellet, and supernatant fractions using the Trovagene test. HR-HPV mRNA testing was performed on brush specimens using the Aptima HPV assay.

RESULTS

HR-HPV prevalence was similar in unfractionated and pellet fractions of all urine samples. For supernatant urine fractions, HR-HPV prevalence appeared lower in mid-stream urine (56.8%[40.8-72.7%]) than in initial stream urine (75.7%[61.9-89.5%]). Sensitivity of CIN2+ detection was identical for initial stream urine and physician-collected cervical specimen (89.9%[95%CI=62.7-99.6%]), and similar to self-collected vaginal specimen (79.1%[48.1-96.6%]).

CONCLUSION

This is among the first studies to compare methodologies for collection and processing of urine for HR-HPV detection. HR-HPV prevalence was similar in first void and initial stream urine, and was highly sensitive for CIN2+ detection. Additional research in a larger and general screening population is needed.

Anaplastic extramedullary cervical ependymoma with leptomeningeal metastasis

We present a rare extramedullary ependymoma with diffuse spinal metastatic disease, and review the previous reports of extramedullary spinal ependymomas. Ependymomas are the most common intramedullary spinal cord tumor in adults. These tumors rarely present as extramedullary masses. We treated a 23-year-old man with a history of progressive neck, shoulder and arm pain, with sensory and motor symptoms in the C7 dermatome. MRI of the cervical spine demonstrated a ventral contrast-enhancing lesion with evidence of enhancement along the dura and spinal cord of the upper cervical spine, thoracic spine, and cauda equina. He underwent a tumor debulking procedure without complications. Following surgery, he received craniospinal radiation to treat the remaining tumor and diffuse leptomeningeal disease. The final pathology of the tumor revealed that is was a World Health Organization Grade III anaplastic ependymoma. At the 1 year follow-up, the patient had stable imaging and had returned to his preoperative functional status. Of the 19 reported patients with primary intradural, extramedullary spinal ependymomas, two had extradural components and seven had anaplastic grades. Only one tumor with an anaplastic grade resulted in metastatic disease, but without spinal recurrence. To our knowledge, this is the first report of an intradural, extramedullary spinal ependymoma with an anaplastic grade, presenting with concomitant diffuse, nodular leptomeningeal metastasis involving the upper cervical spine, thoracic spine, conus medullaris, and cauda equina. Similar to the treatment of intramedullary ependymomas with metastasis, this patient underwent an aggressive debulking procedure followed by radiation therapy to the entire neuroaxis.

Prevalence of human papillomavirus among oesophageal squamous cell carcinoma cases: systematic review and meta-analysis

Background:

Oncogenic human papillomavirus (HPV) has been hypothesised as a risk factor for oesophageal squamous cell carcinoma (OSCC), but aetiological research has been limited by the varying methodology used for establishing HPV prevalence. The aims of this systematic review and meta-analysis were to estimate the prevalence of HPV DNA detected in OSCC tumours and the influence of study characteristics.

Methods:

Study-level estimates of overall and type-specific HPV prevalence were meta-analysed to obtain random-effects summary estimates.

Results:

This analysis included 124 studies with a total of 13 832 OSCC cases. The average HPV prevalence (95% confidence interval) among OSCC cases was 0.277 (0.234, 0.320) by polymerase chain reaction; 0.243 (0.159, 0.326) by in situ hybridisation; 0.304 (0.185, 0.423) by immunohistochemistry; 0.322 (0.154, 0.490) by L1 serology; and 0.176 (0.061, 0.292) by Southern/slot/dot blot. The highest HPV prevalence was found in Africa and Asia, notably among Chinese studies from provinces with high OSCC incidence rates.

Conclusions:

Future research should focus on quantifying HPV in OSCC cases using strict quality control measures, as well as determining the association between HPV and OSCC incidence by conducting large, population-based case–control studies. Such studies will provide a richer understanding of the role of HPV in OSCC aetiology.

Prevalence and incidence of cervical intra-epithelial neoplasia among female sex workers in Korogocho, Kenya

SETTING

Sex Workers Outreach Programme Clinic, Korogocho, Nairobi, Kenya.

OBJECTIVE

In a cohort of sex workers, to determine 1) the prevalence of cervical intra-epithelial neoplasia (CIN) and its association with human immunodeficiency virus-1 (HIV-1) infection, and 2) the incidence rate of CIN during the 3-year follow-up from December 2009 to December 2012.

DESIGN

Prospective nested cohort study.

RESULTS

Of the 350 women enrolled, the median age was 29 years (range 18-49); 84 (24%) were HIV-1-infected. At enrollment, 54 (15%) had an abnormal cytology, 39 (11%) had low-grade intra-epithelial lesions (LSIL) and 15 (4%) high-grade intraepithelial lesions (HSIL). HIV-1-infected women were 2.7 times (95%CI 1.7-4.4) more likely to have CIN than non-HIV-1-infected women. Among HIV-1-infected women, the prevalence of LSIL and HSIL was 2.5 times (95%CI 1.2-5.1) and seven times (95%CI 2.3-23.3) greater than among non-HIV-infected women. During the follow-up period, 39 (11%) women had incident CIN (6.6/100 person years [py]), with no difference by HIV status, i.e., respectively 7.9/100 py and 6.3/100 py in HIV-1-infected and non-HIV-1-infected women.

CONCLUSION

The prevalence and incidence of CIN among HIV-1-infected sex workers was high; early, regular screening and follow-up of this life-threatening condition is therefore recommended.

Multiple human papillomavirus infections and HIV seropositivity as risk factors for abnormal cervical cytology among female sex workers in Nairobi

We estimated type-specific prevalence of human papillomavirus (HPV) and examined risk factors for abnormal cervical cytology among 296 female sex workers from Nairobi, Kenya. Over half (54%) were infected with a high-risk (HR) HPV type, of which HPV16 and 52 were the most common types. HIV-1 prevalence was 23% and HIV-1 sero-positivity was associated with high-grade cervical lesions, particularly among women with CD4 count less than 500 cells/mm(3) (odds ratio [OR] = 6.9; 95% confidence interval [CI]: 1.7-24.9). Among women who had normal cytology at the time of entry into the study, the risk of having an abnormal Pap smear within one year was significantly elevated for women with multiple HPV types at study entry (adjusted odds ratio [aOR] = 6.0; 95% CI: 2.3-15.7) and with a subset of HR HPV types (aOR = 4.2; 95% CI: 1.6-11.2). Detection of multiple concurrent HPV infections may be a useful marker to identify women at risk of developing precancerous lesions in populations of high HPV prevalence.

Ab Initio electronic properties of monolayer phosphorus nanowires in silicon

Epitaxial circuitry offers a revolution in silicon technology, with components that can be fabricated on atomic scales. We perform the first ab initio calculation of atomically thin epitaxial nanowires in silicon, investigating the fundamental electronic properties of wires two P atoms thick, similar to those produced this year by Weber et al. For the first time, we catch a glimpse of disorder-related effects in the wires--a prerequisite for understanding real fabricated systems. Interwire interactions are made negligible by including 40 ML of silicon in the vertical direction (and the equivalent horizontally). Accurate pictures of band splittings and the electronic density are presented, and for the first time the effective masses of electrons in such device components are calculated.

Dorsal thoracic arachnoid web and the "scalpel sign": a distinct clinical-radiologic entity

Arachnoid webs are intradural extramedullary bands of arachnoid tissue that can extend to the pial surface of the spinal cord, causing a focal dorsal indentation of the cord. These webs tend to occur in the upper thoracic spine and may produce a characteristic deformity of the cord that we term the "scalpel sign." We describe 14 patients whose imaging studies demonstrated the scalpel sign. Ten of 13 patients who underwent MR imaging demonstrated T2WI cord signal-intensity changes, and 7 of these patients also demonstrated syringomyelia adjacent to the level of indentation. Seven patients underwent surgery, with 5 demonstrating an arachnoid web as the cause of the dorsal indentation demonstrated on preoperative imaging. Although the webs themselves are rarely demonstrated on imaging, we propose that the scalpel sign is a reliable indicator of their presence and should prompt consideration of surgical lysis, which is potentially curative.

Blockade of MUC1 expression by glycerol guaiacolate inhibits proliferation of human breast cancer cells

We sought to determine whether administration of glycerol guaiacolate at an optimal biological dose inhibits human breast cancer cell growth. Human breast cancer MCF-7 and ZR-75-1 cells were treated with glycerol guaiacolate and the therapeutic efficacy and biological activity of this drug was investigated on breast cancer cell growth. MCF-7 cells were injected into the mammary fat pad of overectamized female athymic nude mice. Ten days later, animals were treated with daily intraperitoneal injections of glycerol guaiacolate for six weeks. Tumor size and volume was monitored and immunohistochemistry analysis on MUC1, p21 and ki-67 was performed. Glycerol guaiacolate decreased breast cancer cell growth in a dose-dependent manner, decreased cell migration, and caused G1 cell cycle arrest. Our results demonstrate that glycerol guaiacolate inhibits MUC1 protein and mRNA expression levels and significantly increased p21 expression in human breast cancer cells as well as induced PARP cleavage. Similarly, glycerol guaiacolate inhibited breast tumor growth in vivo as well as enhanced p21 expression and decreased breast tumor cell proliferation (ki-67 expression). Collectively, our results demonstrate that glycerol guaiacolate decreased MUC1 expression and enhanced cell growth inhibition by inducing p21 expression in breast cancer cells. These findings suggest that glycerol guaiacolate may provide a novel and effective approach for the treatment of human breast cancer.

Ammonia gas permeability of meat packaging materials

Meat products are packaged in polymer films designed to protect the product from exterior contaminants such as light, humidity, and harmful chemicals. Unfortunately, there is almost no data on ammonia permeability of packaging films. We investigated ammonia permeability of common meat packaging films: low-density polyethylene (LDPE; 2.2 mil), multilayer polyolefin (MLP; 3 mil), and vacuum (V-PA/PE; 3 mil, 0.6 mil polyamide/2.4 mil polyethylene). The films were fabricated into 10 × 5 cm pouches and filled with 50 mL deionized water. Pouches were placed in a plexiglass enclosure in a freezer and exposed to 50, 100, 250, or 500 ppm ammonia gas for 6, 12, 24, and 48 h at -17 ± 3 °C and 21 ± 3 °C. At freezing temperatures, no ammonia residues were detected and no differences in pH were found in the water. At room temperature, ammonia levels and pH of the water increased significantly (P < 0.05) with increasing exposure times and ammonia concentrations. Average ammonia levels in the water were 7.77 ppm for MLP, 5.94 ppm for LDPE, and 0.89 ppm for V-PA/PE at 500 ppm exposure for 48 h at 21 ± 3 °C. Average pH values were 8.64 for MLP, 8.38 for LDPE, and 7.23 for V-PA/PE (unexposed ranged from 5.49 to 6.44) at 500 ppm exposure for 48 h. The results showed that temperature influenced ammonia permeability. Meat packaging materials have low ammonia permeability and protect meat products exposed to ammonia leaks during frozen storage.

Discrete-time semi-Markov modeling of human papillomavirus persistence

Multi-state modeling is often employed to describe the progression of a disease process. In epidemiological studies of certain diseases, the disease state is typically only observed at periodic clinical visits, producing incomplete longitudinal data. In this paper we consider fitting semi-Markov models to estimate the persistence of human papillomavirus (HPV) type-specific infection in studies where the status of HPV type(s) is assessed periodically. Simulation study results are presented indicating that the semi-Markov estimator is more accurate than an estimator currently used in the HPV literature. The methods are illustrated using data from the HIV Epidemiology Research Study.

Ultra-low exposure to α-7 nicotinic acetylcholine receptor partial agonists elicits an improvement in cognition that corresponds with an increase in α-7 receptor expression in rodents: implications for low dose clinical efficacy

Αlpha-7 neuronal nicotinic receptors (NNRs) are considered targets for cognitive enhancement in schizophrenia and Alzheimer's disease. AZD0328 is an alpha-7 NNR partial agonist that enhances cognition in rodents and nonhuman primates at sub-microgram to microgram doses. We hypothesized that increased expression of the alpha-7 receptor contributes to this beneficial activity at low doses and tested this by examining the effect of AZD0328 using in vivo and ex vivo binding, RT-PCR and cognitive function in rodents. AZD0328 (0.00178 mg/kg) was subcutaneously administered to mice 4, 24, 48 and 72 hours prior to testing in novel object recognition and produced a significant increase in cognition at 4, 24 and 48 h post-dosing. In vivo binding was examined in rat brain using [(3)H]AZ11637326 and there was a dose-dependent reduction in receptor binding at higher doses of AZD0328 (0.001-3 mg/kg), and a second alpha-7 partial agonist, SSR180711 (0.01-30 mg/kg). Lower doses of both compounds (0.0001 mg/kg) produced a significant increase in binding of [(3)H]AZ11637326. Ex vivo binding using [(125)I]-α-bungarotoxin, showed a significant increase in receptor number (B(max.)) in the frontal cortex or hippocampus with no significant effect on receptor affinity (K(d)) 2 h post administration of AZD0328. [(3)H]AZ11637326 administered 1.5 h following AZD0328 produced a significant increase in specific binding in rat brain regions. We found that the effect on receptor number was long-lasting, with [(125)I]-α-bungarotoxin binding increased in rats given AZD0328 for 2-48 h, but this was not accompanied by increased mRNA synthesis. SSR180711 produced a similar increase in B(max.) and specific binding with no effect on K(d). Therefore, trace dose of alpha-7 partial agonists has rapid onset and produces a profound, sustained effect on novel object recognition in mice that corresponds by dose to an increase in receptor number in rat brain. These findings provide an explanation for the acute and sustained benefit of alpha-7 receptor activation in working memory in nonhuman primates and guidance for drug development initiatives and treatment regimens for nicotinic partial agonists.

In vitro and in vivo metabolism of the radiolytic compound 2-dodecylcyclobutanone

Our knowledge about the metabolism of alkylcyclobutanones (2-ACBs) is limited, and the lack of literature on the metabolism of 2-ACBs causes consumers to doubt the safety of irradiated foods. The objectives of this study were to evaluate the metabolism of 2-dodecylcyclobutanone (2-DCB) and identify any possible metabolite. The 2-DCB was mixed with rat S9 (postmitochondrial supernatant fraction) and beta-nicotinamide adenine dinucleotide phosphate (NADPH) in phosphate buffer (pH 7.4) and incubated for 2 h at 37 degrees C. Then, the incubation mixture was mixed with sodium sulfate and extracted with n-hexane by using a Soxhlet apparatus. The hexane extract was concentrated under nitrogen and injected into the gas chromatography-mass spectrometry (GC-MS) machine running in selective ion monitoring mode (SIM) to measure 2-DCB concentration. The hexane extract from the in vitro and in vivo studies was also derivatized with a silylation reagent and injected into a GC-MS running in full scan mode. The average percentage of 2-DCB recovered from the test incubations was 23%, compared with 50% from the controls. The GC-MS chromatograms of the derivatized samples showed a unique peak in the in vitro test incubations and in the hexane extract of the rat feces that were given 2-DCB. This peak was later identified as 2-doecylcyclobutanol.