Concurrent inhibition of oncogenic and wild-type RAS-GTP for cancer therapy

RAS oncogenes (collectively NRAS, HRAS and especially KRAS) are among the most frequently mutated genes in cancer, with common driver mutations occurring at codons 12, 13 and 611. Small molecule inhibitors of the KRAS(G12C) oncoprotein have demonstrated clinical efficacy in patients with multiple cancer types and have led to regulatory approvals for the treatment of non-small cell lung cancer2,3. Nevertheless, KRASG12C mutations account for only around 15% of KRAS-mutated cancers4,5, and there are no approved KRAS inhibitors for the majority of patients with tumours containing other common KRAS mutations. Here we describe RMC-7977, a reversible, tri-complex RAS inhibitor with broad-spectrum activity for the active state of both mutant and wild-type KRAS, NRAS and HRAS variants (a RAS(ON) multi-selective inhibitor). Preclinically, RMC-7977 demonstrated potent activity against RAS-addicted tumours carrying various RAS genotypes, particularly against cancer models with KRAS codon 12 mutations (KRASG12X). Treatment with RMC-7977 led to tumour regression and was well tolerated in diverse RAS-addicted preclinical cancer models. Additionally, RMC-7977 inhibited the growth of KRASG12C cancer models that are resistant to KRAS(G12C) inhibitors owing to restoration of RAS pathway signalling. Thus, RAS(ON) multi-selective inhibitors can target multiple oncogenic and wild-type RAS isoforms and have the potential to treat a wide range of RAS-addicted cancers with high unmet clinical need. A related RAS(ON) multi-selective inhibitor, RMC-6236, is currently under clinical evaluation in patients with KRAS-mutant solid tumours (ClinicalTrials.gov identifier: NCT05379985).

Chemical remodeling of a cellular chaperone to target the active state of mutant KRAS

The discovery of small-molecule inhibitors requires suitable binding pockets on protein surfaces. Proteins that lack this feature are considered undruggable and require innovative strategies for therapeutic targeting. KRAS is the most frequently activated oncogene in cancer, and the active state of mutant KRAS is such a recalcitrant target. We designed a natural product-inspired small molecule that remodels the surface of cyclophilin A (CYPA) to create a neomorphic interface with high affinity and selectivity for the active state of KRASG12C (in which glycine-12 is mutated to cysteine). The resulting CYPA:drug:KRASG12C tricomplex inactivated oncogenic signaling and led to tumor regressions in multiple human cancer models. This inhibitory strategy can be used to target additional KRAS mutants and other undruggable cancer drivers. Tricomplex inhibitors that selectively target active KRASG12C or multiple RAS mutants are in clinical trials now (NCT05462717 and NCT05379985).

Shortening replacement by emulsion and foam template hydroxypropyl methylcellulose (HPMC)-based oleogels in puff pastry dough. Rheological and texture properties

Shortening plays an essential function in the formulation of sweet laminated bakery products, but has a potential health risk due to their high percentage of saturated fatty acids. In this paper, the feasibility of hydroxypropyl methylcellulose (HPMC) oleogels prepared with emulsion template (ET) and foam template (FT) approaches as fat sources in a puff pastry dough was investigated. Spreadability and thermal properties of control shortening, 100% ET and FT oleogels and shortening/oleogel (50/50) blends were measured. The different systems were applied as the fat source in a puff pastry dough, and their effect on rheological and texture properties was investigated. Results showed that partial replacement of shortening with oleogels could significantly decrease the firmness values (from 115 to 26 N) (P < 0.05) and increased the spreadability of shortening. The methodology to prepare the oleogel (FT or ET) also significantly affected the texture parameters. FT blends had the highest spreadability with significantly lower firmness values and area under the curve. Thermal values showed that both oleogels could slightly increase the melting point of shortening from 47 to 50 °C. The replacement of shortening with oleogel decreases the viscoelasticity of puff pastry dough and increases its thermal stability but does not significantly change dough viscoelasticity in the shortening/oleogel mixture. These results indicated that both oleogels have promising potential to replace shortening in puff pastry dough formulations, but the ET oleogel showed a more similar behavior to the control shortening than the FT oleogel.

In vivo hydrogen peroxide diffusivity in brain tissue supports volume signaling activity

Hydrogen peroxide is a major redox signaling molecule underlying a novel paradigm of cell function and communication. A role for H₂O₂ as an intercellular signaling molecule and neuromodulator in the brain has become increasingly apparent, with evidence showing this biological oxidant to regulate neuronal polarity, connectivity, synaptic transmission and tuning of neuronal networks. This notion is supported by its ability to diffuse in the extracellular space, from source of production to target. It is, thus, crucial to understand extracellular H₂O₂ concentration dynamics in the living brain and the factors which shape its diffusion pattern and half-life. To address this issue, we have used a novel microsensor to measure H₂O₂ concentration dynamics in the brain extracellular matrix both in an ex vivo model using rodent brain slices and in vivo. We found that exogenously applied H₂O₂ is removed from the extracellular space with an average half-life of t_1/2 = 2.2 s in vivo. We determined the in vivo effective diffusion coefficient of H₂O₂ to be D* = 2.5 × 10⁻⁵ cm² s⁻¹. This allows it to diffuse over 100 μm in the extracellular space within its half-life. Considering this, we can tentatively place H₂O₂ within the class of volume neurotransmitters, connecting all cell types within the complex network of brain tissue, regardless of whether they are physically connected. These quantitative details of H₂O₂ diffusion and half-life in the brain allow us to interpret the physiology of the redox signal and lay the pavement to then address dysregulation in redox homeostasis associated with disease processes.

Accessible communication in the transport of non-urgent people with communication impairments

Introduction Paramedics may find innumerous circumstances that require careful consideration of the patient’s clinical condition. Because of that, communication between paramedics and patients in a critical condition must be as clear and effective as possible.

Objectives This study aims to identify the communicative needs of ambulance’s crew members when transporting non-urgent people with communicative impairments and to create a tool that facilitates the communicative process.

Methodology A brainstorming was held at Associação de São Jorge to gather information regarding the needs and difficulties experienced by the ambulance’s crew members. An audio record of this meeting was collected and a qualitative analysis was carried out. Additionally, a questionnaire was fulfilled. Based on these results, a first version of the communicative tool was developed. A pluridisciplinary focus group was held to discuss it, regarding content, form and utility. After this focus group, the second version of the communicative tool was elaborated to be tested by the crew members of this association. As so, a dynamic of three hours was implemented to empower these professionals to use this tool and other communicative strategies.

Results The qualitative analysis of the first meeting collected data recognize as crew member’s needs: communicating basic and immediate needs at clinical level and at colloquial discourse. This data allowed to establish parameters for the construction of the first version of the communicative tool. The referred focus group identified the need to improve it, considering: format, content and also the need to complement this tool with other communicative facilitators (e.g. braille; gestures).

Conclusion This study shows the need of facilitating the communication in non-urgent transportation. Despite the modifications that have to be done, the communicative tool that was developed already shows a positive impact in the ambulance crew and in the community.

Impact of ethylene degreening treatment on sensory properties and consumer response to citrus fruits

Degreening treatment is normally applied to early-season citrus varieties grown in the Mediterranean area in order to enhance the external colour when fruits have already reached internal maturity. Despite profound knowledge about the effect of ethylene on the physico-chemical quality of citrus fruit, less is known about its effect on consumers' expectations in the supermarket or consumer quality perceptions when they eat such fruit. In this study, three mandarin cultivars ('Owari', 'Clemenules' and 'Oronules') with two initial colours at harvest, and one orange cultivar, 'Navelina', were submitted to the degreening treatment under commercial conditions. The effect of treatment on both external and internal qualities perceived by consumers was evaluated. The main physico-chemical parameters were also determined. The degreening treatment slightly affected firmness, total soluble solids or acidity level in 'Owari' and 'Navelina'. However, sensory triangle tests, in which 100-122 consumers compared the internal quality of degreened fruit and control fruit, did not show significant differences between treatments for any of the studied cultivars. A survey based on images of citrus fruit was responded by 340 consumers; it showed that the degreening treatment strongly affected consumers' maturity expectations, which resulted in improved fruit liking expectations and increased the number of consumers willing to buy. The extent of this effect depended on the initial colour of the fruit submitted to degreening. In order to improve liking expectations, fruit should arrive on the market with an external colour index (CI = 1000a/Lb) between +10 and +20. We conclude that the ethylene degreening treatment, which did not have any effect on the internal quality that consumers perceive, is a potent postharvest tool to increase citrus fruit sales at the beginning of the season.

Detection and localisation of hip fractures on anteroposterior radiographs with artificial intelligence: proof of concept

AIM

To investigate the feasibility of applying a deep convolutional neural network (CNN) for detection/localisation of acute proximal femoral fractures (APFFs) on hip radiographs.

MATERIALS AND METHODS

This study had institutional review board approval. Radiographs of 307 patients with APFFs and 310 normal patients were identified. A split ratio of 3/1/1 was used to create training, validation, and test datasets. To test the validity of the proposed model, a 20-fold cross-validation was performed. The anonymised images from the test cohort were shown to two groups of radiologists: musculoskeletal radiologists and diagnostic radiology residents. Each reader was asked to assess if there was a fracture and localise it if one was detected. The area under the receiver operator characteristics curve (AUC), sensitivity, and specificity were calculated for the CNN and readers.

RESULTS

The mean AUC was 0.9944 with a standard deviation of 0.0036. Mean sensitivity and specificity for fracture detection was 97.1% (81.5/84) and 96.7% (118/122), respectively. There was good concordance with saliency maps for lesion identification, but sensitivity was lower for characterising location (subcapital/transcervical, 84.1%; basicervical/intertrochanteric, 77%; subtrochanteric, 20%). Musculoskeletal radiologists showed a sensitivity and specificity for fracture detection of 100% and 100% respectively, while residents showed 100% and 96.8%, respectively. For fracture localisation, the performance decreased slightly for human readers.

CONCLUSION

The proposed CNN algorithm showed high accuracy for detection of APFFs, but the performance was lower for fracture localisation. Overall performance of the CNN was lower than that of radiologists, especially in localizing fracture location.

MON-513 Osteonecrosis after Successful Osseointegrated Dental Implantation

Introduction: Medication-related osteonecrosis of the jaw (MRONJ) is a rare complication of antiresorptive medications. Although typically occurring after invasive dental procedures, there is limited data suggesting MRONJ risk in patients with a successfully osseointegrated dental implant. In this case report, we present the clinical presentation, radiological, pathological, and biochemical data of MRONJ presenting years after successful dental implantation while taking antiresorptive medication for the treatment of osteoporosis. Case Presentation: 77 year-old woman underwent titanium dental implant installation to replace a missing mandibular right first molar with uncomplicated postoperative course in 2011, which healed well. Her rheumatologist prescribed ibandronate in 2010 for treatment of osteopenia. In 11/2014 switched to denosumab 60 mg SQ every 6 months. In 2015, she was referred for evaluation of hyperparathyroidism and also transferred osteoporosis care. With adequate clinical response and tolerance to denosumab, she continued the medication. In 6/2018 she had parathyroidectomy to treat primary hyperparathyroidism after an episode of flank pain suspicious for nephrolithiasis. She experienced no further dental complications until jaw pain developed in 2/2018. Periapical radiographs in 4/2018 showed no signs of bone loss or pathology. However, soft tissue papillae between the implant and the mandibular right second molar was inflamed and bled on contact. Despite removal of granulation tissue, the gingiva continued to bleed. Oral antibiotics were empirically prescribed. Cone beam CT scan in 6/2018 showed an altered osseous trabecular pattern without frank bone loss between the implant and right second mandibular molar, suggestive of MRONJ. Denosumab was discontinued(last dose 5/2018). In 7/2018, the dental implant was removed and bone attached to the implant was submitted for histologic evaluation, demonstrating chronic mucositis and sequestra consistent with MRONJ. In 9/2018, the patient developed purulent drainage at the removal site despite oral antibiotic therapy. On repeat CT scan, progressive bone loss and soft tissue proliferation was noted at the prior site of implant and extending slightly more posterior near the right second mandibular molar. She started IV antibiotics with complete resolution of symptoms to date. This case demonstrates osteonecrosis occurring at the site of a previously successful 7-year-old osseointegrated dental implant in a patient on uninterrupted antiresorptive therapy for 8 years.

Toxic corneal reaction due to exposure to palytoxin

A case is presented of corneal toxicity after exposure to palytoxin. A 42 year-old man came with symptoms of pain and blurred vision in his right eye. He reported that a zoanthid coral from a saltwater aquarium had squirted into his eye. Slit-lamp examination showed a prominent central ring infiltrate of 4×6mm without epithelial defect and satellite sub-epithelial micro-infiltrates. After 2 months of topical treatment with steroids, the stromal ring infiltrate was resolved, but a stromal thinning and residual fibrosis remained. Palytoxin is a potent vasoconstrictor that damages the ionic gradient of the cells, causing cell death. It is crucial to remove the toxin and start an aggressive topical therapy as soon as possible. In addition, considering the potential ocular and systemic adverse effects that this toxin can produce, it would be advisable to inform people of its existence and regulate the distribution of this type of corals.

Abstract P3-14-07: Early detection of chemotherapy-induced cardiotoxicity in breast cancer patients

BACKGROUND

The incidence of cardiotoxicity in patients receiving treatment for breast cancer is unknown. There is not enough evidence about early detection and appropriate management of cardiotoxicity. The aim of this study is to identify early markers of risk of cardiac toxicity.

MATERIAL AND METHOD

Prospective study was conducted between 2014 and 2017 based on a cohort of 97 patients diagnosed with breast cancer treated with chemotherapy. Analytical biomarkers (natriuretic peptide, ultra-sensitive T troponin), echocardiogram parameters (left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS)) and electrocardiogram were performed. Analytical biomarkers were measured each chemotherapy cycle and cardiology test were performed before starting chemotherapy, 3 months afterwards, and then every six months during 5 years.

Cardiotoxicity was defined as a reduction in basal LVEF &gt;10% with LVEF&lt;55% in asymptomatic patients or &gt;5% with LVEF&lt;55% in symptomatic patients.

RESULTS

Patients characteristics are shown in table 1

Patients characteristicsVariablesNo cardiotoxicity (n=88)Cardiotoxicity (n=12)Gender (women/men)88/012/0Median age (range)53 years (29-79)47 years (37-70)Smoker (former smoker)13 (3)2 (2)Arterial hypertension202Dyslipemia160Diabetes62Previous chemotherapy11Prior mediastinal radiation therapy01

. All patients had the basal LVEF in normal range. Median follow-up was 26.5 months (13,5-39,6 months). A total of 10.3% had cardiotoxicity with reduction in basal LVEF &gt;10% with LVEF&lt;55% being asymptomatic and 2.1% were symptomatic. Five of these patients were treated with heart failure therapy: 5 with ACE (angiotensin converting enzyme) inhibitors and 3 with beta- blockers. Two of those (40%) who received specific treatment recovered basal LVEF-levels, 2 maintained LVEF dysfunction, and 1 died during follow-up due to tumor-related causes. In 83.3% of patients, cardiotoxicity occurred within the first year of follow-up.

In 50 patients SLG was calculated, in 30% it was lower than -12% in some measurement phase. In 5 cases the LVEF fell below 55% and the LRP decreased by 12% coincided.

The others patients, although they did not develop cardiotoxicity according to the established criteria, a decrease of the LVEF is observed during the treatment and in the first control, between 3-7%, which subsequently tends to recover spontaneously.

miRNA 21-5p, miRNA-133b, miRNA 210-3p, miRNA 423-5p, and miRNA-663b were analyzed. A model has been evaluated where a correlation between the levels of miRNA-133b, miRNA-21-5p and miRNA-210-3p and the decrease of LVEF in relation to treatment was observed.

CONCLUSIONS

Control by echocardiography and serum markers allowed us to detect early cardiotoxicity events and provide us an opportunity to start heart failure therapy on time with the aim of improving the control and evolution of it.Levels of miR-133b, miR-21-5p and miR-210 may alert for a risk of cardiotoxicity and can help to make decisions about treatments.

Acknowledgements: Project funded by European Comission (Hecatos FP7-HEALTH-2013-INNOVATION-1. Reference: CP-IP 602156-1) and RETICS program (RD12/0019/0025) cofunded by FEDER "una manera de hacer Europa”.

Citation Format: Salvador-Coloma C, Hernándiz A, Tejedor S, Miró V, Palomar L, Salvador A, Sepúlveda P, Santaballa A. Early detection of chemotherapy-induced cardiotoxicity in breast cancer patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-14-07.

Searching for a job: Cardiac responses to acute stress and the mediating role of threat appraisal in young people

Being unemployed and looking for a job has become a source of stress for many people in several European countries. However, little attention has been paid to the impact of this stressful situation on the individuals' psychophysiological stress responses. The aim of this study was to investigate the effect of being an unemployed job seeker on cognitive threat appraisal and cardiac responses to a psychosocial stressor. We exposed a group of unemployed job seekers (N = 42) and a matched group of unemployed non-job seekers (N = 40) to a standardized social stressor in form of job interview, the Trier Social Stress Test. Our results showed that unemployed job seekers manifest lower cardiac responses, along with a lower cognitive threat appraisal, compared to non-job seekers. Moreover, we observed a full mediating role of cognitive threat appraisal on the relationship between being an unemployed job seeker and cardiac responses to stress. These findings reveal that being unemployed and looking for a job has an effect on physiological responses to acute stress, as well as the importance of psychological process related to the situation. These responses might lead to negative health and motivational consequences. Theoretical and practical implications are discussed.

Being an optimist or a pessimist and its relationship with morning cortisol release and past life review in healthy older people

OBJECTIVE

Investigate the relationship between optimism and pessimism and the cortisol awakening response (CAR) and past life review in healthy older people.

DESIGN

76 older volunteers summarised their lives, highlighting the most important events, impressions and experiences. Cortisol saliva samples were collected on two consecutive weekdays. High and low optimism and pessimism groups were computed by mean split.

MAIN OUTCOME MEASURES

Percentages of positive (PE) and negative events (NE) and positive (PCE) and negative cognitions and emotions (NCE) were obtained. Optimism and pessimism were measured with the Life Orientation Test Revised. The areas under the curve with respect to the ground and with respect to the increase were computed, with the latter understood as the CAR.

RESULTS

The high pessimism group reported more NE and NCE and less PE and PCE (p's < 0.041). No significant differences in CAR were found between high and low optimism and pessimism groups after removing suspected non-adherent participants (p's > 0.116). Higher CAR was related to lower PCE, but higher NCE (both p < 0.008).

CONCLUSION

Pessimism seems to increase the focus on negative aspects of the past, which may lead to a worse perception of life in ageing, whereas optimism contributes to a healthier CAR.

Volatile metabolite profiling reveals the changes in the volatile compounds of new spontaneously generated loquat cultivars

In recent years, the advantageous traits of three new loquat cultivars have drawn the attention of breeders and growers. All three have spontaneously arisen from the 'Algerie' cultivar: the new 'Xirlero' cultivar is a bud mutant of 'Algerie', while 'Amadeo' and 'Raúl' arose as chance seedlings. Following a non-targeted approach based on HS-SPME-GC-MS, the volatile compounds profile of the fruits from the new cultivars were obtained and compared to the original 'Algerie' cultivar. Carboxylic acids clearly dominated the volatile profile of all the loquat cultivars, but esters, aldehydes, ketones and alcohols were also predominant compounds. Interestingly when the bud mutant event did not lead to marked changes in the volatile compounds complement, pronounced changes in the volatile composition of chance seedling-generated cultivars 'Amadeo' and 'Raúl' were observed. 'Amadeo' fruits showed lower levels of 2-methyl butanoic acid and much higher levels of methylhexanoate, methylbutanoate and 2-hydroxy-5-methylacetophenone. The 'Raúl' cultivar also had a distinctive volatile profile characterised by high levels of C6-aldehydes, (E)-2-hexanal, 2-hexenal, (Z)-3-hexenal and hexanal, and several carotenoid-derived volatiles; e.g. 2-pentene-1,4-dione 1-(1,2,2-trimethylcyclopentyl), (S)-dihydroactinidiolide, isodurene, cis-geranyl acetone, β-damascenone, β-ionone, α-ionone and 3,4-dehydro-β-ionone. These changes in volatiles were associated with a more intense flavour in cultivars 'Amadeo' and 'Raúl', according to the sensory evaluation of the flavour intensity carried out by a semi-trained panel. A metabolomic correlation network analysis provided insights as to how volatiles were regulated, and revealed that the compounds modified in 'Amadeo' were uncoupled from the rest of the volatilome, while the volatiles modified in 'Raul' changed according to specific groups. To conclude, this work provides a holistic view of how the loquat volatilome was affected, and this information was integrated with the physical-chemical-sensory attributes to understand the changes that occur in the new cultivars.

Assessing the relevance of a multiplexed methodology for proteomic biomarker measurement in the invertebrate species Gammarus fossarum: A physiological and ecotoxicological study

Recently, a protein sequence database was built specifically for the sentinel non-model species Gammarus fossarum using a proteogenomics approach. A quantitative multiplexed targeted proteomics assay (using Selected Reaction Monitoring mass spectrometry) was then developed for a fast and simultaneous quantification of dozens of biomarker peptides specific of this freshwater sentinel crustacean species. In order to assess the relevance of this breakthrough methodology in ecotoxicology, the response patterns of a panel of 26 peptides reporting for 20 proteins from the Gammarus fossarum proteome with putative key functional roles (homeostasis, osmoregulation, nutrition, reproduction, molting,…) were recorded through male and female reproductive cycles and after exposure to environmental concentrations of cadmium and lead in laboratory-controlled conditions. Based on these results, we validated the implication of annotated vtg-like peptides in the oogenesis process, and the implication of Na⁺/K⁺ ATPase proteins in the molt cycle of organisms. Upon metal (cadmium and lead) contamination, peptides belonging to proteins annotated as involved in antioxidant and detoxification functions, immunity and molting were significantly down-regulated. Overall, this multiplex assay allowed gaining relevant insights upon disruption of different main functions in the sentinel species Gammarus fossarum. This breakthrough methodology in ecotoxicology offers a valid and high throughput alternative to currently used protocols, paving the way for future practical applications of proteogenomics-derived protein biomarkers in chemical risk assessment and environmental monitoring.

Neuroimaging evidence of brain abnormalities in mastocytosis

Mastocytosis is a rare disease in which chronic symptoms are related to mast cell accumulation and activation. Patients can display depression-anxiety-like symptoms and cognitive impairment. The pathophysiology of these symptoms may be associated with tissular mast cell infiltration, mast cell mediator release or both. The objective of this study is to perform morphological or functional brain analyses in mastocytosis to identify brain changes associated with this mast cell disorder. We performed a prospective and monocentric comparative study to evaluate the link between subjective psycho-cognitive complaints, psychiatric evaluation and objective medical data using magnetic resonance imaging with morphological and perfusion sequences (arterial spin-labeled perfusion) in 39 patients with mastocytosis compared with 33 healthy controls. In the test cohort of 39 mastocytosis patients with psycho-cognitive complaints, we found that 49% of them had morphological brain abnormalities, mainly abnormal punctuated white matter abnormalities (WMA). WMA were equally frequent in cutaneous mastocytosis patients and indolent forms of systemic mastocytosis patients (42% and 41% of patients with WMA, respectively). Patients with WMA showed increased perfusion in the putamen compared with patients without WMA and with healthy controls. Putamen perfusion was also negatively correlated with depression subscores. This study demonstrates, for we believe the first time, a high prevalence of morphological and functional abnormalities in the brains of mastocytosis patients with neuropsychiatric complaints. Further studies are required to determine the mechanism underpinning this association and to ascertain its specificity.

Unique Combination of Surface Energy and Lewis Acid-Base Characteristics of Superhydrophobic Cellulose Fibers

Cellulose fibers were first functionalized on their surface by silanization with trichloromethylsilane in an optimized gas-solid reaction, and the occurrence of the reaction was assessed using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Then, the changes in the physicochemical surface properties of the material were thoroughly assessed using inverse gas chromatography (IGC) and X-ray photoelectron spectroscopy as surface specific tools. A very surprising combination of results was obtained: (i) the dispersive component of the surface energy was found to decrease from 42 to 14 mJ m^-2 (at 40 °C), the latter figure representing one of the lowest values ever reported (by IGC) for cellulose-based materials, and (ii) both Lewis acidic and Lewis basic characters of the fiber surface, as measured by the injection into the IGC columns of 15 different vapor probes, significantly increased with silanization. Moreover, those remarkable changes in the surface properties of the material were obtained at a low degree of silanization (as shown by ATR-FTIR). The present results may have a great impact in what concerns the application of the described type of superhydrophobic cellulose fibers for the production of new biocomposites: an unusual enhanced compatibility both with low-surface energy polymeric matrices, such as polyolefins, as well as with other types of matrices through Lewis acid-base interactions, can be predicted.

Optimism moderates psychophysiological responses to stress in older people with Type 2 diabetes

Optimism is thought to be beneficial for health, and these effects may be mediated through modifications in psychophysiological stress reactivity. Type 2 diabetes (T2D) is associated with reduced cardiovascular responses to stress and heightened cortisol over the day. This study assessed the relationships between optimism, stress responsivity, and daily cortisol output in people with T2D. A total of 140 participants with T2D were exposed to laboratory stress. Heart rate (HR), systolic (SBP), diastolic blood pressure (DBP), and cortisol were measured throughout the session. Cortisol output over the day was also assessed. Optimism and self‐reported health were measured using the revised Life Orientation Test and the Short Form Health Survey. Optimism was associated with heightened SBP and DBP stress reactivity (ps < .047) and lower daily cortisol output (p = .04). Optimism was not related to HR, cortisol stress responses, or the cortisol awakening response (ps > .180). Low optimism was related to poorer self‐reported physical and mental health (ps < .01). Optimism could have a protective role in modulating stress‐related autonomic and neuroendocrine dysregulation in people with T2D.

Mast cells' involvement in inflammation pathways linked to depression: evidence in mastocytosis

Converging sources of evidence point to a role for inflammation in the development of depression, fatigue and cognitive dysfunction. More precisely, the tryptophan (TRP) catabolism is thought to play a major role in inflammation-induced depression. Mastocytosis is a rare disease in which chronic symptoms, including depression, are related to mast cell accumulation and activation. Our objectives were to study the correlations between neuropsychiatric features and the TRP catabolism pathway in mastocytosis in order to demonstrate mast cells' potential involvement in inflammation-induced depression. Fifty-four patients with mastocytosis and a mean age of 50.1 years were enrolled in the study and compared healthy age-matched controls. Depression and stress were evaluated with the Beck Depression Inventory revised and the Perceived Stress Scale. All patients had measurements of TRP, serotonin (5-HT), kynurenine (KYN), indoleamine 2,3-dioxygenase 1 (IDO1) activity (ratio KYN/TRP), kynurenic acid (KA) and quinolinic acid (QA). Patients displayed significantly lower levels of TRP and 5-HT without hypoalbuminemia or malabsorption, higher IDO1 activity, and higher levels of KA and QA, with an imbalance towards the latter. High perceived stress and high depression scores were associated with low TRP and high IDO1 activity. In conclusion, TRP metabolism is altered in mastocytosis and correlates with perceived stress and depression, demonstrating mast cells' involvement in inflammation pathways linked to depression.

Note. 1-MCP Effect on Chilling Injury Development in ‘Nova’ and ‘Ortanique’ Mandarins

The aim of this work was to evaluate the effect of 1-methylcyclopropene (1-MCP) on chilling injury (CI) incidence, ethylene production, phenylalanine ammonia-lyase (PAL) activity and quality changes on mandarin hybrids, ‘Nova’ and ‘Ortanique’, during cold storage. Fruits were treated for 24h with 1-MCP at 0.5 L/L and then stored at 1 ºC. 1-MCP markedly reduced CI incidence in both cultivars, this effect being more accentuated in ‘Nova’ mandarins, which presented lower tolerance to cold storage. 1-MCPtreated fruit presented less PAL activity parallel to a significant increase in ethylene production. These results suggested that ethylene played an important role in citrus fruit CI development and 1-MCPinduced ethylene production might act as a protector of the fruit against chilling damage. 1-MCP reduced ethanol concentration slightly decreased CO2 production and had no effect on fruit quality characteristics such as TSS, acid content or texture for both cultivars.

Influence of Ripening Stage at Harvest on Chilling Injury Symptoms of Persimmon cv. Rojo Brillante Stored at Different Temperatures

Changes in the quality during storage of persimmon fruits cv. Rojo Brillante harvested at two different maturity stages were studied. Early and late harvested fruit were stored at 1°C or 15°C for different periods of time. Harvest time had a relevant influence on chilling injury (CI) sensitiveness, since CI symptoms were found in fruits stored at 1°C only when they were early harvested. The most important CI manifestation was a drastic decrease of firmness that occurred when fruit were transferred from cold storage to 20°C. Other observed CI symptoms were internal browning, darkness of the skin, flesh structural changes, and increase of ethylene and CO2 production. Harvest date had also a considerable effect on the storage at 15°C, in this way, late harvested fruits maintained good quality for more time than early harvested ones.

Rheological Properties of Batters for Coating Products - Effect of Addition of Corn Flour and Salt

The contributions made by corn flour (0, 3 and 6%) and salt (0 and 5.5%) to the rheological properties of a commercial batter mix were studied. The properties of the wheat flour that are the base of the mix were studied first, then the corn flour, salt and other ingredients were added step by step. All the samples showed a shear-thinning behaviour. An increase in the consistency index was obtained when corn flour was present, while the presence of salt produced a remarkable decrease. No differences in viscoelastic behaviour were found when corn flour up to 6% was added, and the behaviour had a clear elastic component. The addition of salt produced a more viscous behaviour. An increase in the gelatinisation temperature of batters was observed in the formulations with salt.

Confidence and psychosis: a neuro-computational account of contingency learning disruption by NMDA blockade

A state of pathological uncertainty about environmental regularities might represent a key step in the pathway to psychotic illness. Early psychosis can be investigated in healthy volunteers under ketamine, an NMDA receptor antagonist. Here, we explored the effects of ketamine on contingency learning using a placebo-controlled, double-blind, crossover design. During functional magnetic resonance imaging, participants performed an instrumental learning task, in which cue-outcome contingencies were probabilistic and reversed between blocks. Bayesian model comparison indicated that in such an unstable environment, reinforcement learning parameters are downregulated depending on confidence level, an adaptive mechanism that was specifically disrupted by ketamine administration. Drug effects were underpinned by altered neural activity in a fronto-parietal network, which reflected the confidence-based shift to exploitation of learned contingencies. Our findings suggest that an early characteristic of psychosis lies in a persistent doubt that undermines the stabilization of behavioral policy resulting in a failure to exploit regularities in the environment.

Pseudo enantiomeric mixed S/P ligands derived from carbohydrates for the 1,4-addition of phenyl boronic acid to cyclohexenone

Mixed S/P ligands 3 and 10, good catalyst precursors for the Rh(i)-catalysed 1,4-addition of phenylboronic acid to cyclohexenone behave as enantiomers even though both derived from d-sugars.

Surface Treatment and Layer Structure in 2H-GaN Grown on the (0001)Si surface of 6H-SiC by MBE

Heteroepitaxy of hexagonal symmetry materials is more complicated than in the more usual case of cubic systems. In the growth of layers on the (0001) surfaces, the misfit dislocations always exhibit a screw component that leads to rotation of the epilayer in a 3 dimensional growth mode. The size of the islands will depend on many factors among which the substrate surface treatment, prior to growth, may be a predominant one. In this work, a comparative study is carried out for samples grown on plasma treated samples, with and without additional substrate annealing prior to epitaxy. It is found that the defect density can be brought below 109 cm−2, which is better than one order of magnitude in comparison to the layers grown on sapphire substrates. On top of the annealed substrates, the island growth is not obvious. Whereas, misorientations as large as a few degrees can be measured inside the layers on top of non annealed substrates, justifying the occurrence of high densities of threading dislocations.

Supercritical fluid extraction of resveratrol from grape skin of Vitis vinifera and determination by HPLC

Supercritical fluid extraction of resveratrol from grape skin of Vitis vinifera was studied. Extraction variables such pressure, modifier concentration (ethanol), and extraction time were optimised. Final extraction conditions were: 40 degrees C, 150 bar, 7.5% ethanol and extraction time 15 min. Extraction recovery and precision (variation coefficient between 0.2 and 1.0%) were calculated. The resveratrol content in the ethanolic extract was determined by HPLC with UV detection at 306 nm. Acetic acid-methanol-water was used as the mobile phase, and C-18 and C-8 columns were tested, instrumental parameters were optimised, and analytical parameters were calculated (lineal interval 0-75 mg l(-1), detection limit 0.1 mg l(-1), sensitivity 125530 mg(-1) mg l(-1), coefficient variation 0.8-1.6%). Six different varieties of grape skin, from the same geographical area and representative of the wine elaboration, were analysed.