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1.
Redox Biol ; 67: 102918, 2023 11.
Article in English | MEDLINE | ID: mdl-37812879

ABSTRACT

We recently developed a novel keratin-derived protein (KDP) rich in cysteine, glycine, and arginine, with the potential to alter tissue redox status and insulin sensitivity. The KDP was tested in 35 human adults with type-2 diabetes mellitus (T2DM) in a 14-wk randomised controlled pilot trial comprising three 2×20 g supplemental protein/day arms: KDP-whey (KDPWHE), whey (WHEY), non-protein isocaloric control (CON), with standardised exercise. Outcomes were measured morning fasted and following insulin-stimulation (80 mU/m2/min hyperinsulinaemic-isoglycaemic clamp). With KDPWHE supplementation there was good and very-good evidence for moderate-sized increases in insulin-stimulated glucose clearance rate (GCR; 26%; 90% confidence limits, CL 2%, 49%) and skeletal-muscle microvascular blood flow (46%; 16%, 83%), respectively, and good evidence for increased insulin-stimulated sarcoplasmic GLUT4 translocation (18%; 0%, 39%) vs CON. In contrast, WHEY did not effect GCR (-2%; -25%, 21%) and attenuated HbA1c lowering (14%; 5%, 24%) vs CON. KDPWHE effects on basal glutathione in erythrocytes and skeletal muscle were unclear, but in muscle there was very-good evidence for large increases in oxidised peroxiredoxin isoform 2 (oxiPRX2) (19%; 2.2%, 35%) and good evidence for lower GPx1 concentrations (-40%; -4.3%, -63%) vs CON; insulin stimulation, however, attenuated the basal oxiPRX2 response (4%; -16%, 24%), and increased GPx1 (39%; -5%, 101%) and SOD1 (26%; -3%, 60%) protein expression. Effects of KDPWHE on oxiPRX3 and NRF2 content, phosphorylation of capillary eNOS and insulin-signalling proteins upstream of GLUT4 translocation AktSer437 and AS160Thr642 were inconclusive, but there was good evidence for increased IRSSer312 (41%; 3%, 95%), insulin-stimulated NFκB-DNA binding (46%; 3.4%, 105%), and basal PAK-1Thr423/2Thr402 phosphorylation (143%; 66%, 257%) vs WHEY. Our findings provide good evidence to suggest that dietary supplementation with a novel edible keratin protein in humans with T2DM may increase glucose clearance and modify skeletal-muscle tissue redox and insulin sensitivity within systems involving peroxiredoxins, antioxidant expression, and glucose uptake.


Subject(s)
Diabetes Mellitus, Type 2 , Insulin Resistance , Adult , Humans , Glucose/metabolism , Cysteine/metabolism , Pilot Projects , Insulin/metabolism , Muscle, Skeletal/metabolism , Diabetes Mellitus, Type 2/metabolism , Protein Isoforms/metabolism , Dietary Supplements , Oxidation-Reduction , Keratins/metabolism , Keratins/pharmacology
2.
Phys Rev Appl ; 17(4)2022 Apr.
Article in English | MEDLINE | ID: mdl-37965129

ABSTRACT

Most microwave readout architectures in quantum computing or sensing rely on a semiconductor amplifier at 4 K, typically a high-electron mobility transistor (HEMT). Despite its remarkable noise performance, a conventional HEMT dissipates several milliwatts of power, posing a practical challenge to scale up the number of qubits or sensors addressed in these architectures. As an alternative, we present an amplification chain consisting of a kinetic inductance traveling-wave parametric amplifier (KITWPA) placed at 4 K, followed by a HEMT placed at 70 K, and demonstrate a chain-added noise TΣ=6.3±0.5K between 3.5 and 5.5 GHz. While, in principle, any parametric amplifier can be quantum limited even at 4 K, in practice we find the performance of the KITWPA to be limited by the temperature of its inputs and by an excess of noise Tex=1.9K. The dissipation of the rf pump of the KITWPA constitutes the main power load at 4 K and is about 1% that of a HEMT. These combined noise and power dissipation values pave the way for the use of the KITWPA as a replacement for semiconductor amplifiers.

3.
J Infect ; 83(6): 709-737, 2021 12.
Article in English | MEDLINE | ID: mdl-34715239

ABSTRACT

Molecular diagnosis; Viral infection; Chemokines; Disease prognosis; CXCL10; CXCL11; CCL3; CCL4; CCL5; Random forest.


Subject(s)
Chemokine CXCL10 , Adult , Child , Humans
4.
Rev Sci Instrum ; 91(9): 091101, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-33003823

ABSTRACT

The performance of superconducting circuits for quantum computing is limited by materials losses. In particular, coherence times are typically bounded by two-level system (TLS) losses at single photon powers and millikelvin temperatures. The identification of low loss fabrication techniques, materials, and thin film dielectrics is critical to achieving scalable architectures for superconducting quantum computing. Superconducting microwave resonators provide a convenient qubit proxy for assessing performance and studying TLS loss and other mechanisms relevant to superconducting circuits such as non-equilibrium quasiparticles and magnetic flux vortices. In this review article, we provide an overview of considerations for designing accurate resonator experiments to characterize loss, including applicable types of losses, cryogenic setup, device design, and methods for extracting material and interface losses, summarizing techniques that have been evolving for over two decades. Results from measurements of a wide variety of materials and processes are also summarized. Finally, we present recommendations for the reporting of loss data from superconducting microwave resonators to facilitate materials comparisons across the field.

5.
J Low Temp Phys ; 199(3-4)2020.
Article in English | MEDLINE | ID: mdl-33487736

ABSTRACT

We describe the design and measurement of feedhorn-coupled, transition-edge sensor (TES) polarimeters with two passbands centered at 220 GHz and 280 GHz, intended for observations of the cosmic microwave background. Each pixel couples polarized light in two linear polarizations by use of a planar orthomode transducer and senses power via four TES bolometers, one for each band in each linear polarization. Previous designs of this detector architecture incorporated passbands from 27 to 220 GHz; we now demonstrate this technology at frequencies up to 315 GHz. Observational passbands are defined with an on-chip diplexer, and Fourier-transform-spectrometer measurements are in excellent agreement with simulations. We find coupling from feedhorn to TES bolometer using a cryogenic, temperature-controlled thermal source. We determine the optical efficiency of our device is η = 77% ± 6% (75% ± 5%) for 220 (280) GHz, relative to the designed passband shapes. Lastly, we compare two power-termination schemes commonly used in wide-bandwidth millimeter-wave polarimeters and find equal performance in terms of optical efficiency and passband shape.

6.
J Low Temp Phys ; 193(3-4)2018.
Article in English | MEDLINE | ID: mdl-34815585

ABSTRACT

Microwave Kinetic Inductance Detectors (MKIDs) provide a compelling path forward to the large-format polarimeter, imaging, and spectrometer arrays needed for next-generation experiments in millimeter-wave cosmology and astronomy. We describe the development of feedhorn-coupled MKID detectors for the TolTEC millimeter-wave imaging polarimeter being constructed for the 50-meter Large Millimeter Telescope (LMT). Observations with TolTEC are planned to begin in early 2019. TolTEC will comprise ∼7,000 polarization sensitive MKIDs and will represent the first MKID arrays fabricated and deployed on monolithic 150 mm diameter silicon wafers - a critical step towards future large-scale experiments with over 105 detectors. TolTEC will operate in observational bands at 1.1, 1.4, and 2.0 mm and will use dichroic filters to define a physically independent focal plane for each passband, thus allowing the polarimeters to use simple, direct-absorption inductive structures that are impedance matched to incident radiation. This work is part of a larger program at NIST-Boulder to develop MKID-based detector technologies for use over a wide range of photon energies spanning millimeter-waves to X-rays. We present the detailed pixel layout and describe the methods, tools, and flexible design parameters that allow this solution to be optimized for use anywhere in the millimeter and sub-millimeter bands. We also present measurements of prototype devices operating in the 1.1 mm band and compare the observed optical performance to that predicted from models and simulations.

7.
Andrology ; 5(3): 431-438, 2017 05.
Article in English | MEDLINE | ID: mdl-28296285

ABSTRACT

Myeloperoxidase is a major neutrophil protein which generates oxidants that are highly reactive, and if present in seminal fluid, could be potentially damaging to spermatozoa. We recruited young males aged 18-35 years, unscreened for fertility status, for a pilot study measuring seminal plasma myeloperoxidase. On three occasions, over a 3-month period, we measured parameters of semen quality and correlated these with seminal myeloperoxidase protein and activity. After baseline measurement, participants were supplemented daily with 250 mg of vitamin C, a potent scavenger of reactive oxygen species with antiinflammatory activities. Seminal plasma from eight of the 12 participants had measurable concentrations of myeloperoxidase protein, across a broad range (15-250 ng/mL). Median myeloperoxidase protein concentrations were ~45-fold higher in semen samples with low vs. high sperm concentrations. Seminal plasma myeloperoxidase protein concentration was inversely correlated with the percentage of rapidly motile spermatozoa assessed by computer-assisted sperm analysis, and the total number of spermatozoa per ejaculate, but positively correlated with sperm maturity, measured by DNA staining ability. We measured an inverse correlation between semen vitamin C concentration and seminal plasma myeloperoxidase protein concentration, although vitamin C supplementation had no effect on semen quality. Our pilot data suggest that high concentrations of myeloperoxidase were present in the seminal plasma of many of our young participants, and that this may be associated with decreases in semen quality. A larger study is required to confirm these findings.


Subject(s)
Antioxidants/therapeutic use , Ascorbic Acid/therapeutic use , Peroxidase/metabolism , Semen/enzymology , Spermatozoa/drug effects , Adolescent , Adult , Enzyme-Linked Immunosorbent Assay , Humans , Male , Pilot Projects , Semen Analysis , Sperm Motility/drug effects , Young Adult
8.
Micron ; 94: 53-65, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28063337

ABSTRACT

Laser-assisted atom probe tomography (L-APT) was used to examine superconducting TiN/Ti/TiN trilayer films with nominal respective thicknesses of 5/5/5 (nm). Such materials are of interest for applications that require large arrays of microwave kinetic inductance detectors. The trilayers were deposited on Si substrates by reactive sputtering. Electron energy loss microscopy performed in a scanning transmission electron microscope (STEM/EELS) was used to corroborate the L-APT results and establish the overall thicknesses of the trilayers. Three separate batches were studied where the first (bottom) TiN layer was deposited at 500°C (for all batches) and the subsequent TiN/Ti bilayer was deposited at ambient temperature, 250°C, and 500°C, respectively. L-APT rendered an approximately planar TiN/Si interface by making use of plausible mass-spectral assignments to N31+, SiN1+, and SiO1+. This was necessary since ambiguities associated with the likely simultaneous occurrence of Si1+ and N21+ prevented their use in rendering the TiN/Si interface upon reconstruction. The non-superconducting Ti2N phase was also revealed by L-APT. Neither L-APT nor STEM/EELS rendered sharp Ti/TiN interfaces and the contrast between these layers diminished with increased film deposition temperature. L-APT also revealed that hydrogen was present in varying degrees in all samples including control samples that were composed of single layers of Ti or TiN.

9.
Appl Phys Lett ; 1082016.
Article in English | MEDLINE | ID: mdl-27114615

ABSTRACT

We have fabricated a wide-bandwidth, high dynamic range, low-noise cryogenic amplifier based on a superconducting kinetic inductance traveling-wave device. The device was made from NbTiN and consisted of a long, coplanar waveguide on a silicon chip. By adding a DC current and an RF pump tone we are able to generate parametric amplification using three-wave mixing. The devices exhibit gain of more than 15 dB across an instantaneous bandwidth from 4 to 8 GHz. The total usable gain bandwidth, including both sides of the signal-idler gain region, is more than 6 GHz. The noise referred to the input of the devices approaches the quantum limit, with less than 1 photon excess noise. Compared to similarly constructed four-wave mixing amplifiers, these devices operate with the RF pump at ~20 dB lower power and at frequencies far from the signal. This will permit easier integration into large scale qubit and detector applications.

10.
Appl Phys Lett ; 108(22)2016 May 30.
Article in English | MEDLINE | ID: mdl-29332947

ABSTRACT

We present a tunable coupler scheme that allows us to tune the coupling strength between a feedline and a superconducting resonator in situ over a wide range. In this scheme, we shunt the feedline with a 50-Ω lumped-element nonlinear transmission line made from a 20 nm NbTiN film. By injecting a DC current, the nonlinear kinetic inductance changes and the effective impedance shunting the resonator periodically varies from a short to an open, which tunes the coupling strength and coupling quality factor Qc . We have demonstrated Qc tuning over a factor of 40, between Qc ~ 5.5 × 104 and Qc ~ 2.3 × 106, for a 4.5 GHz resonator by applying a DC current less than 3.3 mA. Our tunable coupler scheme is easy to implement and may find broad applications in superconducting detector and quantum computing/information experiments.

11.
Commun Agric Appl Biol Sci ; 80(3): 539-50, 2015.
Article in English | MEDLINE | ID: mdl-27141749

ABSTRACT

Hydroponic systems used for growing potted ornamentals in greenhouses are commonly ebb-and-flow irrigation systems. The drainage water is usually recycled to save water and nutrients. To avoid the spread of pathogens in these closed irrigation systems, disinfection of the recycled water is standard practice. Growers can use slow sand filtration or UV-radiation techniques, but these methods are often either not sulted for specific problems or they require an excessively large investment. The objective of this study was to test less expensive but effective alternative disinfection systems. The efficacy of five disinfection systems against fungi and oomycetes was determined: Aqua-Hort (based on Cu-ions), Reciclean (performic acid), D1-OX Forte (CIO2), ECA (electrochemically activated water = anodic oxidation: hypochlorite and free radicals) and Newtec (also anodic oxidation). These five systems and a no-sterilization control were integrated in small closed ebb-and-flow circuits with nutrient solution reservoirs of 400 L each. Activity against Fusarium was excellent with ECA, good with Newtec and DI-OX Forte, moderate with high doses of Reciclean (250 ppm H2O2 and poor with the Aqua-Hort. There was no Pythium in the ECA and Newtec systems, while still so in the Aqua-Hort system, even at high doses (up to 7 ppm Cu++). Although the Reciclean (up to 100 ppm H2O2) and Aqua-Hort systems did not perform well against the pathogens, they did very well against algae; especially Reciclean was also useful against duckweed in water and liverwort on soil substrates. Concentrations of total Cl were elevated in water, substrate and plants after treatments with ECA and Newtec; other accumulations were Cu (Aqua-Hort), Na and SO4 (DI-OX Forte). However, only on a limited number of plant species these accumulations produced phytotoxic effects.


Subject(s)
Disinfection/methods , Fresh Water/chemistry , Water Purification/methods , Agricultural Irrigation , Fresh Water/microbiology , Fresh Water/parasitology , Fusarium/growth & development , Hydroponics/instrumentation , Pythium/growth & development , Recycling , Water Purification/instrumentation
12.
Phys Rev Lett ; 113(18): 187002, 2014 Oct 31.
Article in English | MEDLINE | ID: mdl-25396390

ABSTRACT

We have generated frequency combs spanning 0.5 to 20 GHz in superconducting λ/2 resonators at T=3 K. Thin films of niobium-titanium nitride enabled this development due to their low loss, high nonlinearity, low frequency dispersion, and high critical temperature. The combs nucleate as sidebands around multiples of the pump frequency. Selection rules for the allowed frequency emission are calculated using perturbation theory, and the measured spectrum is shown to agree with the theory. Sideband spacing is measured to be accurate to 1 part in 10(8). The sidebands coalesce into a continuous comb structure observed to cover at least several frequency octaves.

13.
Phys Rev Lett ; 113(5): 050402, 2014 Aug 01.
Article in English | MEDLINE | ID: mdl-25126902

ABSTRACT

We present measurements of a topological property, the Chern number (C_{1}), of a closed manifold in the space of two-level system Hamiltonians, where the two-level system is formed from a superconducting qubit. We manipulate the parameters of the Hamiltonian of the superconducting qubit along paths in the manifold and extract C_{1} from the nonadiabatic response of the qubit. By adjusting the manifold such that a degeneracy in the Hamiltonian passes from inside to outside the manifold, we observe a topological transition C_{1}=1→0. Our measurement of C_{1} is quantized to within 2% on either side of the transition.

14.
Mucosal Immunol ; 7(2): 227-38, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24220300

ABSTRACT

Viral respiratory tract infections (RTI) pose a high burden on the youngest members of our society. Several risk factors are known for severe viral respiratory disease. However, a large proportion of the severe RTI cannot be explained by these risk factors. A growing body of evidence shows that the composition of the microbiota has a major influence on the training of both the mucosal and the systemic immune response and can thus potentially determine susceptibility for severe viral infections. In this review, we discuss the current evidence regarding the influence of bacterial colonization on the severity of viral respiratory infections.


Subject(s)
Respiratory Tract Infections/immunology , Respiratory Tract Infections/virology , Virus Diseases/immunology , Virus Diseases/virology , Animals , Animals, Newborn , Humans , Infant, Newborn , Microbiota , Mucous Membrane/immunology , Mucous Membrane/microbiology , Mucous Membrane/virology , Respiratory Tract Infections/microbiology , Virus Diseases/microbiology
15.
Cereb Cortex ; 24(8): 2169-77, 2014 Aug.
Article in English | MEDLINE | ID: mdl-23529004

ABSTRACT

Oftentimes, we perceive our environment by integrating information across multiple senses. Recent studies suggest that such integration occurs at much earlier processing stages than once thought possible, including in thalamic nuclei and putatively unisensory cortical brain regions. Here, we used diffusion tensor imaging (DTI) and an audiovisual integration task to test the hypothesis that anatomical connections between sensory-related subcortical structures and sensory cortical areas govern multisensory processing in humans. Twenty-five subjects (mean age 22 years, 22 females) participated in the study. In line with our hypothesis, we show that estimated strength of white-matter connections between the first relay station in the auditory processing stream (the cochlear nucleus), the auditory thalamus, and primary auditory cortex predicted one's ability to combine auditory and visual information in a visual search task. This finding supports a growing body of work that indicates that subcortical sensory pathways do not only feed forward unisensory information to the cortex, and suggests that anatomical brain connectivity contributes to multisensory processing ability in humans.


Subject(s)
Auditory Perception , Brain/anatomy & histology , Visual Perception , Acoustic Stimulation , Auditory Perception/physiology , Brain/physiology , Diffusion Tensor Imaging , Electrooculography , Eye Movements/physiology , Female , Humans , Male , Neural Pathways/anatomy & histology , Neural Pathways/physiology , Neuropsychological Tests , Photic Stimulation , Visual Perception/physiology , White Matter/anatomy & histology , White Matter/physiology , Young Adult
16.
Commun Agric Appl Biol Sci ; 79(2): 207-10, 2014.
Article in English | MEDLINE | ID: mdl-26084099

ABSTRACT

If a grower uses predatory mites, and should use chemical compounds, he needs to be very careful in his choice of products. The selected products have to be efficient against the target pest and at the same time compatible with the present beneficial's. Useful tools for such product selection under greenhouse circumstances are side effects lists. These lists are freely available on the websites of producing companies of biological control agents. But not all products (e.g. newly developed ones) have been tested for side effects. Moreover the information already available in these tables is not based on field tests. For this reason, we have developed a protocol for quick screening of side effects of chemical plant protection products under field conditions. For these experiments we have chosen the predatory mite Amblyseius swirskii as test organism, because this is an often used phytoseiid mite, which is very sensitive to pesticides. Hibiscus rosa sinensis is the standard reference plant in our side effects trials because the chosen predatory mite has shown very good control of pests on this plant species. The experimental design consists of eight test objects in 4 replications. Test object 1 is a positive reference (water spray) and test object 2 a negative reference (deltamethrin spray, a product with long residual activity against beneficial organisms). The plot size is 0,68 m2 and each plot contains 32 Hibiscus plants. The greenhouse temperature is set at 20±2°C. The test strategy has the following sequence: introduction of an overdose of Amblyseius swirskii mites 14 days before spraying the pesticides > precount of predatory mites 4 days before application (4DBA) > spray application (A) for the 6 test products and for the 2 references > counting's after application (1, 2, 4, 8 en 12 weeks after application = 1 till 12WAA). The counting's of the number of predatory mites are performed on 20 Hibiscus leaves/plot under a binocular. Because of the absence of any food sources for the A. swirskii mites, it's necessary to re-introduce a high dose of predatory mites in the Hibiscus crop every 4 weeks, especially 2 weeks before the counting's 4, 8 and 12WAA; these introductions are carried out by hanging out 7 sachets with predatory mites (250 mites/sachet or 2500 mites/m2) on each test plot and after 10 days they are removed. In our first experiments the following commercial products have been tested: Pyrethro Pur (rapeseed oil + pyrethrins), Actara (thiamethoxam), Rizolex 500 SC (tolclofos-methyl), Topsin 500 SC (thiophanate-methyl), Floramite 240 SC (bifenazate), Cycocel 75 (chlorrmequat chloride), Vertimec (abamectin), Match (lufenuron), Nocturn (pyridalyl), Neemazal-T/S (azadirachtin), Tracer (spinosad), Envidor (spirodiclofen), Carex 10SC (pyridaben), Nissorun (hexythiazox) and Scelta (cyflumetofen). As expected the water treatment was safest for A. swirskii and deltamethrin killed most of the mites, even if they were re-introduced after 8 or 12 weeks. Also pyrethrins and spinosad showed very negative effects. Abamectin and bifenazate showed intermediate negative effects and should be used with caution. The other products were safe to use in combination with predatory mites. These screening tests will be repeated yearly with new and popular products of which the side effects in practice are currently uncertain.


Subject(s)
Hibiscus/parasitology , Mites/drug effects , Pesticides/toxicity , Plant Diseases/parasitology , Animals , Hibiscus/growth & development , Mites/physiology , Pest Control , Plant Diseases/prevention & control , Plant Leaves/growth & development , Plant Leaves/parasitology
17.
Osteoarthritis Cartilage ; 21(12): 1834-40, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24012622

ABSTRACT

BACKGROUND: A subset of patients with total hip arthroplasty (THA) or total knee arthroplasty (TKA) has suboptimal postoperative results in terms of Patient Reported Outcomes (PROs), and psychological factors could contribute to these suboptimal results. OBJECTIVES: To examine the prevalence of anxiety and depressive symptoms in patients undergoing primary THA or TKA preoperatively and postoperatively, and the relationship between preoperative anxiety and depressive symptoms on PROs of THA and TKA. DESIGN: In this prospective study patients were measured preoperatively, and 3 and 12 months postoperatively. Patients filled in the Hospital Anxiety and Depression Scale, Knee injury and Osteoarthritis Outcome Score (KOOS) or Hip disability and Osteoarthritis Outcome Score (HOOS) and a satisfaction questionnaire. RESULTS: Data were obtained from 149 hip and 133 knee patients. The prevalence of anxiety symptoms decreased significantly from 27.9% to 10.8% 12 months postoperatively in hip patients, and from 20.3% to 14.8% in knee patients. Depressive symptoms decreased significantly from 33.6% to 12.1% 12 months postoperatively in hip patients, and from 22.7% to 11.7% in knee patients. In hip and knee patients, preoperative depressive symptoms predicted smaller changes in different HOOS or KOOS subscales and patients were less satisfied 12 months postoperatively. CONCLUSIONS: Preoperatively, the prevalence of anxiety and depressive symptoms was high. At 3 and 12 months postoperatively, the prevalence of anxiety and depressive symptoms was decreased in both hip and knee patients. However, patients with preoperative anxiety and depressive symptoms had worse PROs 3 and 12 months after THA and TKA and were less satisfied than patients without anxiety or depressive symptoms.


Subject(s)
Anxiety/psychology , Arthroplasty, Replacement, Hip/psychology , Arthroplasty, Replacement, Knee/psychology , Depression/psychology , Osteoarthritis, Hip/psychology , Osteoarthritis, Knee/psychology , Aged , Aged, 80 and over , Anxiety/epidemiology , Depression/epidemiology , Female , Humans , Longitudinal Studies , Male , Middle Aged , Osteoarthritis, Hip/surgery , Osteoarthritis, Knee/surgery , Patient Satisfaction , Prevalence , Prospective Studies , Surveys and Questionnaires , Treatment Outcome
18.
Gait Posture ; 38(2): 310-5, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23829981

ABSTRACT

Our previous study showed that 6 months after total hip arthroplasty (THA) or total knee arthroplasty (TKA), patients reported having less difficulty with daily activities, showed better functional capacity, and performed activities in their natural environment faster compared to preoperatively. However, their actual daily activity level was not significantly improved. Six months is a rather short follow-up period and the discrepancy in recovery among different aspects of functioning might be explained by this limited duration of follow-up. The objective of the present study was to examine the recovery of different aspects of physical functioning at a follow-up nearly 4 years after THA/TKA. Special attention was given to the actual daily activity level, and whether it had increased 4 years after THA/TKA compared to 6 months postoperatively. Seventy-seven (35 hip, 42 knee) patients who were measured preoperatively and postoperatively (6 months after surgery) in a previous study were invited to participate; 44 patients (23 hip, 21 knee) agreed to participate. The 4-year follow-up data were compared with the preoperative and 6-month postoperative data. The daily activity level after 4 years was found to be actually lower than at 6 months post-surgery (128 min vs. 138 min activity per 24h; p-value 0.48). However, the patients continued to improve in other aspects of physical functioning. In conclusion, 4-year post-surgery patients continued to improve on perceived physical functioning, capacity, and performance of activities in daily life. However, even in this relatively healthy study population, patients did not adopt a more active lifestyle 4 years after surgery.


Subject(s)
Activities of Daily Living , Osteoarthritis, Hip/surgery , Osteoarthritis, Knee/surgery , Adult , Aged , Arthroplasty, Replacement, Hip/rehabilitation , Arthroplasty, Replacement, Knee/rehabilitation , Exercise Test , Female , Humans , Longitudinal Studies , Male , Middle Aged , Recovery of Function , Treatment Outcome
19.
J Lipid Res ; 53(5): 979-983, 2012 May.
Article in English | MEDLINE | ID: mdl-22375030

ABSTRACT

The extent of hypercholesterolemia varies considerably in patients with familial hypercholesterolemia (FH). We hypothesized that the variability of the FH phenotype might be partly explained by variation in proprotein convertase subtilisin kexin type 9 (PCSK9) activity. Individuals between 18 and 53 years of age who had been tested for a pathogenic LDLR or APOB mutation were eligible. Mutation carriers with a LDL-C level below the 75(th) percentile (called "FH low") were selected, as well as those with LDL-C above the 90(th) percentile (called "FH high"). Relatives who tested negative for the mutation were the "controls." PCSK9 plasma levels were assessed in 267 individuals who did not receive cholesterol-lowering treatment at the time of the study. Mean PCSK9 plasma levels (95% CI) were lower in the FH-low group compared with the FH-high group [152 (137-167) ng/ml vs. 186 (165-207) ng/ml, P = 0.010] and the control group [177 (164-190) ng/ml, P = 0.013]. Mean PCSK9 levels did not statistically differ between the FH-high and control groups (P = 0.50). Plasma PCSK9 levels are positively associated with LDL-C levels in FH patients and might contribute to the phenotypic severity in this disorder. Therefore, the results of pharmaceutical inhibition of PCSK9 in FH patients are eagerly awaited.


Subject(s)
Hyperlipoproteinemia Type II/blood , Hyperlipoproteinemia Type II/genetics , Phenotype , Proprotein Convertases/blood , Serine Endopeptidases/blood , Adolescent , Adult , Carotid Intima-Media Thickness , Cholesterol, LDL/blood , DNA Mutational Analysis , Female , Genetic Testing , Humans , Hyperlipoproteinemia Type II/physiopathology , Male , Middle Aged , Proprotein Convertase 9 , Young Adult
20.
Osteoarthritis Cartilage ; 19(9): 1102-7, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21723401

ABSTRACT

OBJECTIVE: An earlier study showed that 6 months after total hip arthroplasty (THA) patients' overall daily activity level had not increased, despite significant improvement in their perceived physical functioning. This discrepancy might be because postoperative recovery is not expressed by a more overall active lifestyle, but by the fact that patients could perform the individual activities of daily living (ADL) faster and/or for a longer period of time. The aim of this study was to assess whether patients perform ADL faster and/or for a longer period of time 6 months post-THA compared to baseline. Also examined was whether patients perform activities on the level of healthy matched controls. METHOD: Thirty patients were measured at home with an accelerometry-based Activity Monitor, pre-operatively and 6 months post-THA. Patients were matched with healthy controls on gender and age (±2 years). RESULTS: Compared with baseline, 6 months post-THA the stride frequency and body motility during walking of patients had increased [56.1 (54.3, 57.8)strides/min vs 52.1 (50.3, 54.1)strides/min; P-value<0.0001, and 0.265 (0.245, 0.286)g vs 0.219 (0.197, 0.240)g; P-value<0.0001], and they rose faster from a chair [2.6 (2.5, 2.8)s vs 3.0 (2.8, 3.2)s; P-value<0.0001]. Compared with controls, preoperative all patients had lower values for these parameters. Six months post-THA the stride frequency and body motility during walking were similar to that of controls, but patients rose slower from a chair than controls. CONCLUSION: Six months post-THA patients walked faster and rose from a chair faster compared to baseline. Patients walked as fast as healthy controls but took longer rising from a chair.


Subject(s)
Activities of Daily Living , Arthroplasty, Replacement, Hip/rehabilitation , Osteoarthritis, Hip/rehabilitation , Recovery of Function/physiology , Aged , Case-Control Studies , Female , Follow-Up Studies , Humans , Male , Middle Aged , Monitoring, Ambulatory , Motor Activity/physiology , Osteoarthritis, Hip/surgery , Postoperative Period , Prospective Studies , Treatment Outcome , Walking/physiology
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