Externally validated prediction models for pre-eclampsia: systematic review and meta-analysis.

OBJECTIVE: This systematic review and meta-analysis aimed to evaluate the performance of existing externally validated prediction models for pre-eclampsia (specifically for any- early- late-onset and preterm pre-eclampsia). METHODS: A systematic search was conducted in five databases (MEDLINE, Embase, Emcare, CINAHL, and Maternity and Infant Care Database) to identify studies based on Population, Index model, Comparator, Outcome, Timing, and Setting (PICOTS) approach until May 20, 2023. We extracted data using the CHARMS checklist and appraised risk of bias using PROBAST tool. Discrimination and calibration performance were meta-analysed when appropriate. RESULTS: Twenty-three publications reported 52 externally validated prediction models on pre-eclampsia (twenty any-onset, seventeen early-onset, fourteen late-onset, and one preterm pre-eclampsia). No model had the same set of predictors. Fifteen, two, and three any-onset pre-eclampsia models were externally validated once, twice, and thrice, respectively, and the Fetal Medicine Foundation (FMF) preterm model was widely validated in sixteen different settings. The most common predictors were maternal characteristics (pre-pregnancy BMI, prior pre-eclampsia, family history of pre-eclampsia, chronic medical conditions, and ethnicity) and biomarkers (uterine artery pulsatility index and pregnancy-associated plasma protein-A). The model for preterm pre-eclampsia (triple test FMF) had the best performances with a pooled area under the receiver operating characteristics curve (AUROC) of 0.90 (95% prediction interval (PI) 0.76 - 0.96) and was well-calibrated. The other models generally had poor to fair discrimination performance (AUROC median 0.66, range 0.53 to 0.77) and were overfitted in calibration after external validation. Apart from the FMF model, only the two most validated models in any-onset pre-eclampsia using isolated maternal characteristics, produced reasonable pooled AUROCs of 0.71 (95% PI 0.66 - 0.76) and 0.73 (0.55 - 0.86). CONCLUSION: Existing externally validated prediction models for any-, early-, and late-onset pre-eclampsia have limited discrimination and calibration performance with inconsistent input variables. The triple test FMF model had excellent discrimination performance in predicting preterm pre-eclampsia in numerous settings, but the inclusion of specialised biomarkers may limit feasibility and implementation outside of high-resource settings. This article is protected by copyright. All rights reserved.

Online physical exercise intervention in older adults during lockdown: Can we improve the recipe?

BACKGROUND: Recorded and live online physical exercise (PE) interventions are known to provide health benefits. However, the effects of prioritizing the number of live or recorded sessions remain unclear. AIMS: To explore which recorded-live sessions ratio leads to the best implementation and benefits in older adults. METHODS: Forty-six community-dwelling adults (> 60y.o.) were randomized into two groups completing a 12-week online PE intervention. Each group had a different ratio of live-recorded online sessions as follows: Live-Recorded-Live sessions (LRL; n = 22) vs. Recorded-Live-Recorded sessions (RLR; n = 24). RESULTS: Drop-out rates did not reach significance (LRL:14% vs. RLR: 29%, p = 0.20), and adherence was similar (> 85%) between groups. Both groups reported similar levels of satisfaction (> 70%), enjoyment (> 75%), and perceived exertion (> 60%). Both groups increased physical health and functional capacities, with greater improvements in muscle power (LRL: LRL: + 35 ± 16.1% vs. RLR: + 7 ± 13.9%; p = 0.010) and endurance (LRL: + 34.7 ± 15.4 vs. RLR: + 27.0 ± 26.5, p < 0.001) in the LRL group. DISCUSSION: Both online PE intervention modalities were adapted to the participants' capacities and led to a high level of enjoyment and retention. The greater physical improvements observed in the LRL group are likely due to the higher presence of the instructor compared to the RLR group. Indeed, participants received likely more feedback to appropriately adjust postures and movements, increasing the quality of the exercises. CONCLUSION: When creating online PE interventions containing both recorded and live sessions, priority should be given to maximizing the number of live sessions and not the number of recorded sessions.

[Sleep disorders in patients with a neurocognitive disorder]. / Les troubles du sommeil chez les patients atteints d'un trouble neurocognitif.

INTRODUCTION: Sleep disorders are prevalent in patients with a neurocognitive disorder, and diagnosis and treatment in these patients remain challenging in clinical practice. METHODS: This narrative review offers a systematic approach to diagnose and treat sleep disorders in neurocognitive disorders. RESULTS: Alzheimer's disease is often associated with circadian rhythm disorders, chronic insomnia, and sleep apnea-hypopnea syndrome. Alpha-synucleinopathies (e.g., Parkinson's disease and Lewy body dementia) are often associated with a rapid eye movement sleep behavior disorder, restless legs syndrome, chronic insomnia, and sleep apnea-hypopnea syndrome. A focused history allows to diagnose most sleep disorders. Clinicians should ensure to gather the following information in all patients with a neurocognitive disorder: (1) the presence of difficulties falling asleep or staying asleep, (2) the impact of sleep disturbances on daily functioning (fatigue, sleepiness and other daytime consequences), and (3) abnormal movements in sleep. Sleep diaries and questionnaires can assist clinicians in screening for specific sleep disorders. Polysomnography is recommended if a rapid eye movement sleep behavior disorder or a sleep apnea-hypopnea syndrome are suspected. Sleep complaints should prompt clinicians to ensure that comorbidities interfering with sleep are properly managed. The main treatment for moderate to severe obstructive sleep apnea-hypopnea syndrome remains continuous positive airway pressure, as its efficacy has been demonstrated in patients with neurocognitive disorders. Medications should also be reviewed, and time of administration should be optimized (diuretics and stimulating medications in the morning, sedating medications in the evening). Importantly, cholinesterase inhibitors (especially donepezil) may trigger insomnia. Switching to morning dosing or to an alternative drug may help. Cognitive-behavioral therapy for insomnia is indicated to treat chronic insomnia in neurocognitive disorders. False beliefs regarding sleep should be addressed with the patient and their caregiver. The sleep environment should be optimized (decrease light exposure at night, minimize noise, avoid taking vital signs, etc.). Sleep restriction can be considered as patients with a neurocognitive disorder often spend too much time in bed. The need for naps should be assessed case by case as naps may contribute to insomnia in some patients but allow others to complete their diurnal activities. Trazodone (50mg) may also be used under certain circumstances in chronic insomnia. Recent evidence does not support a role for exogenous melatonin in patients with a neucognitive disorder and insomnia. Patients in long-term care facilities are often deprived of an adequate diurnal exposure to light. Increasing daytime exposure to light may improve sleep and mood. Patients with circadian rhythm disorders can also benefit from light therapy (morning bright light therapy in case of phase delay and evening bright light therapy in case of phase advance). Rapid eye movement sleep behavior disorder can lead to violent behaviors, and the sleeping environment should be secured (e.g., mattress on the floor, remove surrounding objects). Medication exacerbating this disorder should be stopped if possible. High dose melatonin (6 to 18mg) or low dose clonazepam (0.125-0.25mg) at bedtime may be used to reduce symptoms. Melatonin is preferred in first-line as it is generally well tolerated with few side effects. Patients with restless legs syndrome should be investigated for iron deficiency. Medication decreasing dopaminergic activity should be reduced or stopped if possible. Behavioral strategies such as exercise and leg massages may be beneficial. Low-dose dopamine agonists (such as pramipexole 0.125mg two hours before bedtime) can be used to treat the condition, but a prolonged treatment may paradoxically worsen the symptoms. Alpha-2-delta calcium channel ligands can also be used while monitoring for the risk of falls. CONCLUSION: Multiple and sustained nonpharmacological approaches are recommended for the treatment of sleep disturbances in patients with neurocognitive disorder. Pharmacological indications remain limited, and further randomized clinical trials integrating a multimodal approach are warranted to evaluate the treatment of sleep disorders in specific neurocognitive disorders.

The PREvention Program for Alzheimer's RElated Delirium (PREPARED) cluster randomized trial: a study protocol.

BACKGROUND: Delirium is a significant cause of morbidity and mortality among older people admitted to both acute and long-term care facilities (LTCFs). Multicomponent interventions have been shown to reduce delirium incidence in the acute care setting (30-73%) by acting on modifiable risk factors. Little work, however, has focused on using this approach to reduce delirium incidence in LTCFs. METHODS: The objective is to assess the effectiveness of the multicomponent PREPARED Trial intervention in reducing the following primary outcomes: incidence, severity, duration, and frequency of delirium episodes in cognitively impaired residents. This 4-year, parallel-design, cluster randomized study will involve nursing staff and residents in 45-50 LTCFs in Montreal, Canada. Participating public and private LTCFs (clusters) that provide 24-h nursing care will be assigned to either the PREPARED Trial intervention or the control (usual care) arm of the study using a covariate constrained randomization procedure. Approximately 400-600 LTC residents aged 65 and older with dementia and/or cognitive impairment will be enrolled in the study and followed for 18 weeks. Residents must be at risk of delirium, delirium-free at baseline and have resided at the facility for at least 2 weeks. Residents who are unable to communicate verbally, have a history of specific psychiatric conditions, or are receiving end-of-life care will be excluded. The PREPARED Trial intervention consists of four main components: a decision tree, an instruction manual, a training package, and a toolkit. Primary study outcomes will be assessed weekly. Functional autonomy and cognitive levels will be assessed at the beginning and end of follow-up, while information pertaining to modifiable delirium risk factors, medical consultations, and facility transfers will be collected retrospectively for the duration of the follow-up period. Primary outcomes will be reported at the level of intervention assignment. All researchers analyzing the data will be blinded to group allocation. DISCUSSION: This large-scale intervention study will contribute significantly to the development of evidence-based clinical guidelines for delirium prevention in this frail elderly population, as it will be the first to evaluate the efficacy of a multicomponent delirium prevention program translated into LTC clinical practice on a large scale. TRIAL REGISTRATION: NCT03718156 , ClinicalTrials.gov .

Front-line emergency department nurses' and physicians' assessments of processes of elder-friendly care for quality improvement.

INTRODUCTION: Geriatric emergency department (ED) care has gained increasing importance and interest due to increasing visits in seniors. AIM: Among ED front-line nurses and physicians, to assess and compare ratings of elder-friendly care process indicators, variability in ratings, and concurrent validity of ratings. METHODS: Four Quebec EDs' full-time registered nurses and physicians rated their geriatric care using 9 subscales. Nurse and physician subscale scores were compared. Inter-rater variability within disciplines and variability between nurses and physicians were measured. Associations between the subscale scores and perceived overall quality of care were tested. RESULTS: 38 nurses and 36 physicians completed the survey (83% of 89 eligible). Scores differed by discipline for 3 of 9 subscales computed; nurses had higher mean scores on Protocols, Family-Centered Discharge, and Staff Education. Very high variation for Staff Education was found within disciplines. Variations for Family-Centered Discharge differed significantly between nurses and physicians. Almost all subscale scores were significantly positively associated with perceived overall quality of care. CONCLUSIONS: ED nurses and physicians rate geriatric care components similarly except for protocols, discharge processes, and continuing education. The subscales have concurrent validity. Results suggest a need for improvement in continuing educational strategies with a particular attention to discharge processes.

Description of a new species Coomansus batxatensis (Mononchida, Mononchidae) from Vietnam, with an updated key to species.

Coomansus batxatensis sp. nov., recorded from Vietnam, is described and illustrated and its phylogenetic relationship within the Mononchida is analysed. The molecular data (18S and 28S ribosomal DNA) are provided for the new species. The new species is characterized by small body size (body length, L = 0.7-0.9 mm); buccal cavity sub-rectangular in shape, flattened at base, 21-24 × 12-13 µm or 1.9 (1.7-2.0) times as long as wide; posterior position of dorsal tooth apex (59-63% from the base of buccal cavity); pars refringens vaginae with faint and small (2.5 × 1.7 µm) teardrop-shaped pieces, short pars distalis vaginae; and males with short spicules (50-51.5 µm) with rounded head and conical blade part. The new species is close to Coomansus parvus but differs from it by the smaller buccal cavity size, more posterior position of the dorsal tooth apex, longer tail and presence of males. An updated identification key to Coomansus species and a compendium of all the species known are presented.

A comparison of physical exercise and cognitive training interventions to improve determinants of functional mobility in healthy older adults.

OBJECTIVES: Mobility is a complex but crucial clinical outcome in older adults. Past observational studies have highlighted that cardiorespiratory fitness (CRF), energy cost of walking (ECW), and cognitive switching abilities are associated with mobility performance, making these key determinants of mobility intervention targets to enhance mobility in older adults. The objective of this study was to compare, in the same design, the impact of three training methods - each known to improve either CRF, ECW, or cognitive switching abilities - on mobility in healthy older adults. METHODS: Seventy-eight participants (69.28 ± 4.85yo) were randomly assigned to one of three twelve-week interventions: Aerobic Exercise (AE; n = 26), Gross Motor Abilities (GMA; n = 27), or Cognitive (COG; n = 25) training. Each intervention was designed to improve one of the three key determinants of mobility (CRF, ECW, and cognitive switching). Primary outcomes (usual gait speed, and TUG performance) and the three mobility determinants were measured before and after the intervention. RESULTS: Repeated-measures ANOVAs showed a time effect for TUG performance (F(1,75) = 14.92, p < .001): all groups equally improved after the intervention (ΔTUGpost-pre, in seconds, with 95% CI: AE = -0.44 [-0.81 to -0.08]; GMA = -0.60 [-1.10 to -0.10]; COG = -0.33 [-0.71 to 0.05]). No significant between group differences were observed. CRF was improved in the AE group only (Hedges' G = 0.27, small effect), ECW and cognitive switching improved the most in the GMA (Hedges' G = -0.78, moderate effect) and COG groups (Hedges' G = -1.93, large effect) respectively. Smaller improvements in ECW were observed following AE and COG trainings (Hedges' G: AE = -0.39, COG = -0.36, both small effects) as well as in cognitive switching following AE and GMA training (Hedges' G: AE = -0.42, GMA = -0.21, both small effects). DISCUSSION: This study provides further support to the notion that multiple interventional approaches (aerobic, gross motor exercise, or cognitive training) can be employed to improve functional mobility in older adults, giving them, and professionals, more options to promote healthy ageing.

Mind the Rhythm: ECG QT Dispersion and Cognition in Healthy Older Adults.

BACKGROUND: Autonomic function has been linked to cognitive abilities in aging. Even in non-clinical states, a certain variability in heart rhythm regulation can be measured with QT dispersion (QTcD), an ECG marker of ventricular repolarization which has been linked to autonomic function and cardiovascular health. QTcD has been shown to be higher in individuals with mild cognitive impairment, and the highest in individuals with Alzheimer's disease. The goal of this study was to see if QTcD is associated with cognitive performance in healthy individuals. METHODS: Sixty-three healthy inactive older adults (> 60 years) completed an extensive cognitive assessment (including inhibition, divided attention, updating, working memory, and processing speed), a physical fitness assessment, and underwent a resting ECG. RESULTS: After controlling for age, sex, and education, QTcD significantly predicted global cognition (MoCA) scores (R 2 = 0.17, F ( 4 . 58 ) = 3.00, p < 0.03, ß = -0.36). Exploratory analysis on the MoCA subcomponents revealed a significant association between the visual/executive subcomponent and QTcD (R 2 = 0.12, F (1 .6 1) = 7.99, p < 0.01, ß = -0.34). In individuals with high QTcD, QTcD values were linked to executive functions (R 2 = 0.37), processing speed (R 2 = 0.34), and dual-task performances (R 2 = 0.47). No significant associations were found within the low QTcD group. CONCLUSION: This study shows an association between ventricular repolarization (QTcD) and cognitive performance, in particular speed and executive functions, in healthy older adults. The results provide further support for linking autonomic heart regulation and age-related cognitive changes, and suggest that deviations on ECG, even within-normal range, could help detect early cognitive deficits.

Experiences of an Emergency Department Visit Among Older Adults and Their Families: Qualitative Findings From a Mixed-Methods Study.

BACKGROUND: Emergency department (ED) visits are critical events for older adults, but little is known regarding their experiences, particularly about their physical needs, the involvement of accompanying family members, and the transition back to the community. OBJECTIVE: To explore experiences of an ED visit among patients aged 75 and older. METHODS: In a mixed-methods study, a cohort of patients aged 75 and older (or a family member) discharged from the ED back to the community was recruited from 4 urban EDs. A week following discharge, structured telephone interviews supplemented with open-ended questions were conducted. A subsample (76 patients, 32 family members) was purposefully selected. Verbatim transcripts of responses to the open-ended questions were thematically analyzed. RESULTS: Experiences related to physical needs included comfort, equipment supporting mobility and autonomy, help when needed, and access to drink and food. Family members required opportunities to provide patient support and greater involvement in their care. At discharge, patients/families required adequate discharge education, resolution of their health problem, information on medications, and greater certainty about planned follow-up medical and home care services. CONCLUSIONS: Our findings suggest several areas that could be targeted to improve patient and family perceptions of the care at an ED visit.

Peptide-modified electrolyte-gated organic field effect transistor. Application to Cu2+ detection.

This work proposes an approach for Cu2+ sensing in water which combines the selectivity of the Gly-Gly-His (GGH) peptide probe with the sensitivity of the electrolyte-gated organic field-effect transistor (EGOFET). The oligopeptide probe was immobilized onto the gate electrode of the transistor by electrooxidation of the primary amine of the glycine moiety. Cu2+ complexation by the grafted GGH was at first electrochemically evidenced, using cyclic and square wave voltammetries, then it was demonstrated that GGH-functionalized EGOFETs can transduce Cu2+ complexation through a significant threshold voltage shift and therefore a change in drain current. The limit of detection is ca. 10-12 M and the sensitivity in the linear range (10-12 - 10-8 M) is 1 mA dec-1 (drain current variations).

Inactivation of Vibrio sp. in pure cultures and mussel homogenates using high hydrostatic pressure.

The objective of this study was to determine the effect of high hydrostatic pressure (HHP) on the inactivation of Vibrio sp. in pure cultures and mussel homogenates. Four Vibrio strains including V. alginolyticus, V. cholerae, V. parahaemolyticus and V. vulnificus were used. HHP treatments were performed with both pure Vibrio sp. cultures in alkaline peptone water (2% NaCl) and artificially inoculated mussel homogenates at pressure levels of 250, 350 and 450 MPa for 1 and 3 min at 25°C. Counts of Vibrio were determined before and after treatment using drop plating method. The effect of high pressure on the reduction level significantly differed among the respective Vibrio species. Vibrio vulnificus was the most susceptible species to HHP. To achieve a >5 log reduction in mussel homogenates, pressure treatment needs to be (i) 350-450 MPa for ≥1 min at 25°C for both V. alginolyticus and V. cholerae, (ii) 250 MPa for ≥3 min or 350-450 MPa for ≥1 min for V. vulnificus and (iii) 350 MPa for ≥3 min or 450 MPa for ≥1 min for V. parahaemolyticus. SIGNIFICANCE AND IMPACT OF THE STUDY: High hydrostatic pressure (HHP) has been applied to inactivate spoilage and pathogenic micro-organisms in a variety of food products, including seafood. Vibrio sp. are frequently reported as the main cause of foodborne illness associated with consumption of raw or undercooked seafood particularly shellfish worldwide. To date, data on the inactivation of Vibrio sp. via HHP are still limited and most of the trials only investigated HHP application in oysters and clams. This study demonstrates the efficacy of HHP inactivating Vibrio sp. in both pure culture and mussel homogenates.

How Older Adults Experience an Emergency Department Visit: Development and Validation of Measures.

STUDY OBJECTIVE: This study aims to develop and validate measures of experiences of an emergency department (ED) visit suitable for use by older adults or their family members. METHODS: A cohort of patients aged 75 years and older who were discharged home was recruited at 4 EDs. At 1 week after the visit, patients or family members were interviewed by telephone to assess problems experienced at the visit. Twenty-six questions based on 6 domains of care found in the literature were developed: 16 questions were administered to all patients; 10 questions were administered to bed patients only. Scales were developed with multiple correspondence analysis. Regression analyses were used to validate the scales, using 2 validation criteria: perceived overall quality of care and willingness to return to the same ED. RESULTS: Four hundred twelve patients completed the 1-week interview, 197 ambulatory and 215 bed patients; family members responded for 75 patients. Two scales were developed, assessing personal care and communication (8 questions; α=.63) and waiting times (2 questions; α=.79). Both scales were significantly independently associated with perceived overall quality of care and willingness to return to the same ED. CONCLUSION: Two scales assessing important aspects of ED care experienced by older adults are ready for further evaluation in other settings.

A comparison of the impact of physical exercise, cognitive training and combined intervention on spontaneous walking speed in older adults.

BACKGROUND: Spontaneous walking speed (SWS) is one of the most important indicators of health in older adults. Studies have shown benefits of physical trainings on SWS in older adults but the impact of cognitive training and multidomain interventions remains understudied. AIMS: This original study aimed at comparing the impact of aerobic/resistance exercise, computerized cognitive training and the combination of both interventions compared with active control conditions on SWS in healthy older adults. METHODS: Ninety community-dwelling older adults were randomly assigned to four different combinations composed of two active interventions: physical aerobic/resistance and cognitive dual-task trainings, and two active control conditions: stretching exercises and computer lessons. The four combinations were the following: (1) aerobic/resistance and cognitive dual task (n = 28), (2) aerobic/resistance and computer lessons (n = 21), (3) stretching exercises and cognitive dual task and (n = 23), (4) stretching exercises and computer lessons (n = 18). Training sessions were held three times/week for three months. SWS for 30 s was assessed before and after the intervention. RESULTS: Repeated-measures ANOVA showed a main effect of time and a significant three-way interaction suggesting differential improvement in SWS according to training combinations. A clinical meaningful improvement in SWS was observed in groups 1-3 (0.08-0.14 m/s; effect sizes: small to moderate) but not in the active control group 4. DISCUSSION: Results of this study suggest that aerobic/resistance exercise and computerized dual-task training are two non-pharmacological interventions by which SWS, a functional vital sign, can be clinically improved in older adults. CONCLUSION: This original study pointed out different tools to prevent functional decline in older people.

Elder-Friendly Emergency Department: Development and Validation of a Quality Assessment Tool.

OBJECTIVES: To develop and validate a comprehensive quality assessment tool for emergency department (ED) geriatric care. DESIGN: Four-step study: (1) Content development of tool by a multidisciplinary panel, (2) survey of ED lead physicians and nurses, (3) development of subscales using principal component analysis and clinical judgment, (4) reliability and validity assessment. SETTING: Province of Quebec, Canada. PARTICIPANTS: Lead ED nurses and physicians at 76 Quebec EDs who participated in a 2013/14 survey (66% of 116 adult nonpsychiatric EDs in the province). MEASUREMENTS: Geriatric care items (n = 62) grouped into seven preliminary content areas (screening and assessment, clinical protocols, discharge planning, staffing, physical environment, continuing education, quality assessment), lead nurse and physician perceptions of the quality of ED geriatric care, institutional prioritization of geriatric care, and ED type. RESULTS: Thirteen subscales were developed; most were associated with ED type and quality indicators. CONCLUSION: Thirteen subscales for geriatric ED services are proposed for evaluation in various ED settings.

Crystal Phase Quantum Well Emission with Digital Control.

One of the major challenges in the growth of quantum well and quantum dot heterostructures is the realization of atomically sharp interfaces. Nanowires provide a new opportunity to engineer the band structure as they facilitate the controlled switching of the crystal structure between the zinc-blende (ZB) and wurtzite (WZ) phases. Such a crystal phase switching results in the formation of crystal phase quantum wells (CPQWs) and quantum dots (CPQDs). For GaP CPQWs, the inherent electric fields due to the discontinuity of the spontaneous polarization at the WZ/ZB junctions lead to the confinement of both types of charge carriers at the opposite interfaces of the WZ/ZB/WZ structure. This confinement leads to a novel type of transition across a ZB flat plate barrier. Here, we show digital tuning of the visible emission of WZ/ZB/WZ CPQWs in a GaP nanowire by changing the thickness of the ZB barrier. The energy spacing between the sharp emission lines is uniform and is defined by the addition of single ZB monolayers. The controlled growth of identical quantum wells with atomically flat interfaces at predefined positions featuring digitally tunable discrete emission energies may provide a new route to further advance entangled photons in solid state quantum systems.

Enzyme-less electrochemical displacement heterogeneous immunosensor for diclofenac detection.

We describe an electrochemical immunosensor based on functionalization of a working electrode by electrografting two functional diazonium salts. The first one is a molecular probe, diclofenac, coupled with an arylamine onto which a specific antibody is immobilized by affinity interactions; the second is a redox probe (a quinone) also coupled with an arylamine, able to transduce the hapten-antibody association into a change in electroactivity. The steric hindrance induced by the antibody leads to a current decrease upon binding of the antibody on the grafted molecular probe; conversely, when diclofenac is present in solution, a displacement equilibrium occurs between the target diffusing into the solution and the grafted probe. This leads to dissociation of the antibody from the electrode surface, event which is transduced into a current increase ("signal-on" detection). The detection limit is ca. 20 fM, corresponding to 6pgL-1 diclofenac, which is competitive compared to other label-free immunosensors. We demonstrate that the sensor is selective and is able to quantify diclofenac in tap water.

The Association between Generalized Anxiety Disorder, Subthreshold Anxiety Symptoms and Fear of Falling among Older Adults: Preliminary Results from a Pilot Study.

OBJECTIVE: A relationship between generalized anxiety disorder (GAD) and fear of falling (FOF) has long been proposed but never specifically studied. This study aimed at analyzing the relationship between FOF and GAD or anxiety symptoms, while controlling for major depressive episodes (MDE), depressive symptoms, fall risk, and sociodemographic variables. METHODS: Twenty-five older adults participated in this pilot study. Assessments included the following: Anxiety Disorder Interview Schedule, Geriatric Anxiety Inventory, Geriatric Depression Scale, Falls-Efficacy Scale-International. A multidisciplinary team evaluated fall risk. RESULTS: FOF was significantly correlated with GAD, MDE, anxiety and depressive symptoms, and fall risk, but not with sociodemographic variables. Multiple regression analyses indicated that GAD and anxiety symptoms were significantly and independently associated with FOF. CONCLUSION: Although the results of this pilot study should be replicated with larger samples, they suggest that FOF is associated with GAD and anxiety symptoms even when considering physical factors that increase the risk of falling. CLINICAL IMPLICATIONS: Treatment of FOF in patients with GAD may present a particular challenge because of the central role of intolerance of uncertainty, which may prevent patients from regaining confidence despite the reduction of fall risk. Clinicians should screen for GAD and anxiety symptoms in patients with FOF to improve detection and treatment.

Effect of organoclay on morphology and properties of linear low density polyethylene and Vietnamese cassava starch biobased blend.

Linear low density polyethylene (LLDPE)/thermal plastic starch (TPS) blend was studied to prepare the biobased nanocomposite material using organoclay nanofil15 (N15) modified by alkilammonium as the reinforced phase. The LLDPE/TPS blend and its nanocomposites were elaborated by melt mixing method at 160 °C for 7 min. And the compounded sample was filmed by blowing method at three different zones of temperature profile which are 160-170-165 °C. The good dispersion of clay in the polymer blend matrix is showed by X-ray diffraction (XRD) and transmission electronic microscopy (TEM), and a semi-exfoliated structure was obtained. The thermal and mechanical properties of materials are enhanced when N15 is added to the mixture. The effect of N15 on morphology and particles size of TPS phase is also investigated. The biodegradation test shows that more than 60% in weight of LLDPE/TPS film is degraded into CO2, H2O, methane and biomass after 5 months in compost soil.

Reduced turn-around time for Mycobacterium tuberculosis drug susceptibility testing with a proportional agar microplate assay.

Multidrug-resistant tuberculosis is a major issue worldwide; however, accessibility to drug susceptibility testing (DST) is still limited in developing countries, owing to high costs and complexity. We developed a proportion method on 12-well microplates for DST. The assay reduced the time to results to <12 days and <10 days when bacterial growth was checked with the naked eye or a microscope, respectively. Comparison with the Canetti-Grosset method showed that the results of the two assays almost overlapped (kappa index 0.98 (95% CI 0.91-1.00) for isoniazid, rifampicin, streptomycin; and kappa index 0.92 (95% CI 0.85-0.99) for ethambutol). The sequencing of genes involved in drug resistance showed similar level of phenotype-genotype agreement between techniques. Finally, measurement of the MICs of rifampicin and ethambutol suggests that the currently used critical ethambutol concentration should be revised, and that the current molecular drug susceptibility tests for rifampicin need to be re-evaluated, as in vitro rifampicin-sensitive isolates could harbour drug resistance-associated mutation(s).

Identification of novel esterase-active enzymes from hot environments by use of the host bacterium Thermus thermophilus.

Functional metagenomic screening strategies, which are independent of known sequence information, can lead to the identification of truly novel genes and enzymes. Since E. coli has been used exhaustively for this purpose as a host, it is important to establish alternative expression hosts and to use them for functional metagenomic screening for new enzymes. In this study we show that Thermus thermophilus HB27 is an excellent screening host and can be used as an alternative provider of truly novel biocatalysts. In a previous study we constructed mutant strain BL03 with multiple markerless deletions in genes for major extra- and intracellular lipolytic activities. This esterase-diminished strain was no longer able to grow on defined minimal medium supplemented with tributyrin as the sole carbon source and could be used as a host to screen for metagenomic DNA fragments that could complement growth on tributyrin. Several thousand single fosmid clones from thermophilic metagenomic libraries from heated compost and hot spring water samples were subjected to a comparative screening for esterase activity in both T. thermophilus strain BL03 and E. coli EPI300. We scored a greater number of active esterase clones in the thermophilic bacterium than in the mesophilic E. coli. From several thousand functionally screened clones only two thermostable α/ß-fold hydrolase enzymes with high amino acid sequence similarity to already characterized enzymes were identifiable in E. coli. In contrast, five further fosmids were found that conferred lipolytic activities in T. thermophilus only. Four open reading frames (ORFs) were found which did not share significant similarity to known esterase enzymes but contained the conserved GXSXG motif regularly found in lipolytic enzymes. Two of the genes were expressed in both hosts and the novel thermophilic esterases, which based on their primary structures could not be assigned to known esterase or lipase families, were purified and preliminarily characterized. Our work underscores the benefit of using additional screening hosts other than E. coli for the identification of novel biocatalysts with industrial relevance.