The Frailty Reduction via Implementation of Exercise, Nutrition, and Deprescribing (FRIEND) Trial: Study Protocol and Recruitment Results

INTRODUCTION

Virtually all adults in aged care facilities are frail, a condition which contributes to falls, cognitive decline, hospitalisation, and mortality. Polypharmacy, malnutrition, sedentariness, and sarcopenia are risk factors amenable to intervention. The Asia-Pacific Frailty Management Guidelines recommend anabolic exercise and the optimisation of medications and nutrition. However, no study has evaluated this best practice intervention triad in aged care.

METHODS

The Frailty Reduction via the Implementation of Exercise, Nutrition, and Deprescribing (FRIEND) Trial (ANZCTR No.ACTRN12622000926730p) is a staged 6-month translational trial evaluating resident outcomes, staff/caregiver knowledge, and institutional implementation in a Townsville aged care facility. Residents received high-intensity resistance exercise and balance training and medication and nutrition optimisation co-implemented by investigators (exercise physiologist, geriatrician, pharmacist, and nutritionist) and facility staff. Staff and caregivers completed comprehensive education modules and training. We report the trial protocol and recruitment results.

RESULTS

29 residents (21 female, age: 88.6 ± 6.3 years) were recruited. At baseline, the residents were frail (frailty scale nursing home (FRAIL-NH); 6.3 ± 2.4/14), cognitively impaired (Montreal Cognitive Assessment; 13.8 ± 6.8/30), functionally impaired (Short Physical Performance Battery; 4.9 ± 3.1/12, 6 min walk distance; 222.2 ± 104.4 m), and were prescribed numerous medications (15.5 ± 5.9). Two residents died and one withdrew before the intervention's commencement. Thirty family members and 19 staff (carers, allied health assistants, nurse managers, registered nurses, lifestyle-leisure officers, kitchen/hospitality staff, and senior leadership) were recruited to receive frailty education modules.

CONCLUSIONS

The FRIEND trial is currently being implemented with results expected in mid-2024. This is the first trial to evaluate the implementation of the best practice frailty guidelines including anabolic exercise and medication/nutritional optimisation in residential aged care.

Aluminum nitride nanowire light emitting diodes: Breaking the fundamental bottleneck of deep ultraviolet light sources

Despite broad interest in aluminum gallium nitride (AlGaN) optoelectronic devices for deep ultraviolet (DUV) applications, the performance of conventional Al(Ga)N planar devices drastically decays when approaching the AlN end, including low internal quantum efficiencies (IQEs) and high device operation voltages. Here we show that these challenges can be addressed by utilizing nitrogen (N) polar Al(Ga)N nanowires grown directly on Si substrate. By carefully tuning the synthesis conditions, a record IQE of 80% can be realized with N-polar AlN nanowires, which is nearly ten times higher compared to high quality planar AlN. The first 210 nm emitting AlN nanowire light emitting diodes (LEDs) were achieved, with a turn on voltage of about 6 V, which is significantly lower than the commonly observed 20 – 40 V. This can be ascribed to both efficient Mg doping by controlling the nanowire growth rate and N-polarity induced internal electrical field that favors hole injection. In the end, high performance N-polar AlGaN nanowire LEDs with emission wavelengths covering the UV-B/C bands were also demonstrated.

Exciton kinetics, quantum efficiency, and efficiency droop of monolayer MoS₂ light-emitting devices

We have investigated the quantum efficiency of monolayer MoS2 light-emitting devices through detailed temperature and power-dependent photoluminescence studies and rate equation analysis. The internal quantum efficiency can reach 45 and 8.3% at 83 and 300 K, respectively. However, efficiency droop is clearly measured with increasing carrier injection due to the unusually large Auger recombination coefficient, which is found to be ∼10(-24) cm(6)/s at room temperature, nearly 6 orders of magnitude higher than that of conventional bulk semiconductors. The significantly elevated Auger recombination in the emerging two-dimensional (2D) semiconductors is primarily an indirect process and is attributed to the abrupt bounding surfaces and the enhanced correlation, mediated by magnified Coulomb interactions, between electrons and holes confined in a 2D structure.

Highly efficient, spectrally pure 340 nm ultraviolet emission from AlxGa₁-xN nanowire based light emitting diodes

High crystal quality, vertically aligned AlxGa1-xN nanowire based double heterojunction light emitting diodes (LEDs) are grown on Si substrate by molecular beam epitaxy. Such AlxGa1-xN nanowires exhibit unique core-shell structures, which can significantly suppress surface nonradiative recombination. We successfully demonstrate highly efficient AlxGa1-xN nanowire array based LEDs operating at ∼340 nm. Such nanowire devices exhibit superior electrical and optical performance, including an internal quantum efficiency of ∼59% at room temperature, a relatively small series resistance, highly stable emission characteristics, and the absence of efficiency droop under pulsed biasing conditions.

Hall effect measurements on Bridgman-grown CuInSe2 with sodium

The presence of sodium, either in the substrate or as a co-evaporant during absorber deposition, has been shown to improve the performance of polycrystalline photovoltaic devices made with Cu(In, Ga)Se(2), as well as the ternary CuInSe(2). Investigations have shown Na or Na compounds deposited on the grain boundaries, but none have been found within intact crystal grains, leading to suggestions that grain boundaries may play a role in the improved performance of the cells. Therefore, in this study, ingots containing large monocrystals of CuInSe(2) have been grown, using a vertical-Bridgman method, from melts that also include a varying quantity of sodium. In order to simulate the conditions under which cells are constructed, a proportion of Se above stoichiometry has been added to some of the melts. Resistivity and Hall effect measurements were then performed on the material after growth. The results show no large change in either resistivity or majority hole concentration in either set of samples, although a slight decrease in the latter value was apparent in the excess Se samples with 0.2 and 0.3 at.% Na additions. No clear trend in hole mobility could be discerned, although an increase was seen with 0.2 at.% Na addition for both samples.

Fabrication of a nanocomposite from in situ iron nanoparticle reinforced copper alloy

In situ iron nanoparticle reinforced Cu-3Sn-8Zn-6Pb alloy has been fabricated by centrifugal casting in a vacuum chamber with a medium frequency electrical furnace. The microstructure of this alloy was analyzed with a scanning electron microscope (SEM) and a high-resolution transmission electron microscope (HRTEM), and the results show that the grains of Cu-3Sn-8Zn-6Pb alloy without iron have a typical dendrite structure with dimensions from 500 to 1500 microm, and the grains of the alloy with the addition of 1% iron are small and equiaxed, with dimensions from 20 to 60 microm. Then, the relatively uniform dispersed particles in the copper matrix were identified with the HRTEM to be pure iron with dimensions in the order of 2-20 nm. The mechanical properties of the alloys were measured and the results show a significant increase in the tensile strength of the alloy with iron nanoparticles and a slight increase of the elongation compared to that without iron. The mechanism of formation of the iron nanoparticles was analyzed by thermodynamic and dynamic theories, and the results indicate that the in situ iron nanoparticles of Cu-3Sn-8Zn-6Pb alloy can reasonably form during solidification in the centrifugal casting technique.

Kinetic scheme for intermolecular RNA cleavage by a ribozyme derived from hepatitis delta virus RNA

A minimal kinetic mechanism for a trans-acting ribozyme derived from the HDV antigenomic RNA self-cleaving element was established from steady-state, pre-steady-state, single-turnover, and binding kinetics. Rate constants for individual steps, including substrate binding and dissociation, cleavage, and product release and binding, were measured at 37 degrees C at pH 8.0 in 10 mM Mg(2+) using oligonucleotides as either substrates, noncleavable analogues or 3' product mimics. A substrate containing a normal 3',5'-linkage was cleaved with a first-order rate constant (k(2)) of 0.91 min(-)(1). The association rate constant for the substrate to the ribozyme (2.1 x 10(7) M(-)(1) min(-)(1)) was at the lower range of the expected value for RNA duplex formation, and the substrate dissociated with a rate constant (1.4 min(-)(1)) slightly faster than that for cleavage. Thus the binary complex was not at equilibrium with free enzyme and substrate prior to the cleavage step. Following cleavage, product release was kinetically ordered in that the 5' product was released rapidly (>12 min(-)(1)) relative to the 3' product (6.0 x 10(-)(3) min(-)(1)). Rapid 5' product release and lack of a demonstrable binding site for the 5' product could contribute to the difficulty in establishing the ribozyme-catalyzed reverse reaction (ligation). Slow release of the 3' product was consistent with the extremely low turnover under steady-state conditions as 3' product dissociation was rate-limiting. The equilibrium dissociation constant for the substrate was 24-fold higher than that of the 3' cleavage product. A substrate with a 2',5'-linkage at the cleavage site was cleaved with a rate constant (k(2)) of 1.1 x 10(-)(2) min(-)(1). Thus, whereas cleavage of a 3',5'-linkage followed a Briggs-Haldane mechanism, 2', 5' cleavage followed a Michaelis-Menten mechanism.

Imidazole rescue of a cytosine mutation in a self-cleaving ribozyme

Ribozymes use a number of the same catalytic strategies as protein enzymes. However, general base catalysis by a ribozyme has not been demonstrated. In the hepatitis delta virus antigenomic ribozyme, imidazole buffer rescued activity of a mutant with a cytosine-76 (C76) to uracil substitution. In addition, a C76 to adenine substitution reduced the apparent pKa (where Ka is the acid constant) of the self-cleavage reaction by an amount consistent with differences in the pKa values of these two side chains. These results suggest that, in the wild-type ribozyme, C76 acts as a general base. This finding has implications for potential catalytic functions of conserved cytosines and adenines in other ribozymes and in ribonuclear proteins with enzymatic activity.

Hemodialysis-related nodulocystic acne treated with isotretinoin

Some hemodialysis patients, without taking any acnegenic agents, developed severe nodulocystic acne with unknown causes. Because nodulocystic acne poorly responds to conventional acne therapy and increases the black pigmentation in the face, it severely interferes with the quality of life of these patients. To investigate whether isotretinoin is effective in treating hemodialysis patients with severe nodulocystic acne, we undertook a prospective, randomized, single-blind study. A total of 20 patients with nodulocystic acne participated in the study, of whom 18 completed it. Ten patients received isotretinoin 10 mg/day (5 mg/capsule) for 3 months as a study group and the other 10 took placebo for 3 months as a control group. The severity of acne and treatment-related side effects were evaluated monthly by a questionnaire and laboratory evaluation which included liver function tests, blood lipids and blood platelet counts. The results showed isotretinoin treatment significantly reduced the severity of acne of the study group patients after 1 month (scales of acne severity: 4.0 +/- 0.0 vs. 3.13 +/- 0.35, p < 0. 01) and 3 months (4.0 +/- 0.0 vs. 1.5 +/- 0.76, p < 0.01) of follow-up. In addition, the severity of acne of the study group patients was significantly less than that of the control group patients after 1 month (3.13 +/- 0.35 vs. 3.80 +/- 0.42, p < 0.01) and 3 months (1.5 +/- 0.76 vs. 3.70 +/- 0.48, p < 0.001) of treatment. Only mild side effects were noted. No significant changes of biochemical evaluation were found except that a mild elevation of aspartate aminotransferase was noted in the study group patients. However, two study group patients withdrew from the trial because of isotretinoin-related side effects and toxic hepatitis. In summary, our study first demonstrated that the small dose of isotretinoin effectively treated nodulocystic acne of hemodialysis patients and the side effects were mild. This result suggests that isotretinoin may be the treatment of choice for nodulocystic acne in end-stage renal disease patients with renal replacement therapy. The liver function and other isotretinoin-related side effects in these patients should be carefully monitored.

Expression of Mel-CAM in implantation site intermediate trophoblastic cell line, IST-1, limits its migration on uterine smooth muscle cells

An immortalized implantation site intermediate trophoblastic cell line, IST-1, was established from a human placenta of 7 weeks gestation. IST-1 cells phenotypically resembled the implantation site intermediate trophoblastic cells in situ and expressed Mel-CAM (MUC 18 or CD146). Mel-CAM is a cell adhesion molecule belonging to the immunoglobulin gene superfamily. It is involved in heterophilic cell-cell adhesion and plays a role in several biological processes including tumor progression. We have previously shown that Mel-CAM was highly expressed in the intermediate (extravillous) trophoblast in the human implantation site. In this study we determined the function of Mel-CAM in the interaction of trophoblast and uterine smooth muscle in the implantation site. IST-1 cells failed to adhere to immobilized recombinant Mel-CAM in solid phase whereas the uterine smooth muscle cells did. The presence of the putative Mel-CAM ligand in smooth muscle cells was further supported by the finding that Mel-CAM-transfected but not the mock-transfected U937 leukemia cells bind to the confluent monolayer of uterine smooth muscle cells. IST-1 cells attached efficiently to the monolayer of the uterine smooth muscle cells and acquired a spindle-shaped morphology simulating smooth muscle cells. The cell binding was only marginally affected by Mel-CAM blocking antibodies. However, Mel-CAM blocking antibodies and recombinant Mel-CAM promoted cell migration from IST-1 cell spheroids on the smooth muscle monolayer. Taken together, our results suggest that IST-1 cells express Mel-CAM but not the putative Mel-CAM ligand. In contrast, the uterine smooth muscle cells express the putative Mel-CAM ligand which binds to Mel-CAM on the surface of the IST-1 cells. The interaction between Mel-CAM and its putative ligand confers a stationary phenotype for trophoblastic cells. These observations are consistent with an important role for Mel-CAM in limiting trophoblastic migration within the myometrium in the implantation site.

Experimental investigation of radiation from the interaction of an electron beam and a conducting grating

Recent experimental results on the radiation generated from an electron beam passing closely over a conducting grating are presented. The most striking results are that the output power is 4 orders of magnitude more intense than that predicted by the Smith-Purcell explanation and that the output power increases exponentially with the beam thickness until it saturates at a thickness of a 1000 times the grating period. The recent theoretical model of Chang and McDaniel [Phys. Rev. Lett. 63, 1066 (1989); J. Opt. Soc. Am. B 7, 239 (1990)] is shown to compare favorably with these results.