Prognostic value of the bone turnover markers in multiple myeloma

Background: Multiple myeloma (MM) is characterized by osteolytic bone disease resulting from increased osteoclast activity and reduced osteoblast function. Aim: The aim of our research was to determine connection between bone turnover markers and presence of bone lesions, their degree of severity, to monitor MM bone disease and to assess effectiveness of anti-myeloma treatment. Materials and Methods: Serum samples and clinical data from 123 patients with newly diagnosed MM were collected at Riga East Clinical University Hospital (Riga, Latvia) from June 2014 to June 2016. Bone lesions detected by radiography, CT scans, MRI, and PET/CT were divided into degrees from 0 to 3 (0 - no bone involvement, 1 - ≤ 3 bone lesions, 2 - ≥ 3 bone lesions, 3 - fracture). Staging was performed applying Durie/Salmon (DS) and International Staging System classifications. Progressive disease was defined as development of one or more new bone lesions. The levels of bone metabolic markers β-isomerized C-terminal telopeptide of collagen type I (β-CTX) and bone-specific alkaline phosphatase (bALP) were monitored regularly in the year. Results: Bone lesions were found in 86 (69%) patients. From these 6 (4%) patients had 1st degree, 11 (9%) had 2nd degree and 69 (56%) had 3rd degree bone lesions. Level of the bone resorption marker β-CTX in the control group was 0.41 ng/ml, which is lower than in MM patients (p 0.05). However, β-CTX was found to be an excellent diagnostic marker for MM (AUC 0.91; 95% confidence interval, 0.88-0.94; p < 0.001). Conclusions: Patients with MM and bone lesions have increased value of bone resorption marker β-CTX. There is a correlation between bone resorption marker and degree of bone lesions. Changes in β-CTX levels may be used to monitor the effectiveness of myeloma treatment.publishersversionPeer reviewe

Prognostic value of the bone turnover markers in multiple myeloma

Background: Multiple myeloma (MM) is characterized by osteolytic bone disease resulting from increased osteoclast activity and reduced osteoblast function. Aim: The aim of our research was to determine connection between bone turnover markers and presence of bone lesions, their degree of severity, to monitor MM bone disease and to assess effectiveness of anti-myeloma treatment. Materials and Methods: Serum samples and clinical data from 123 patients with newly diagnosed MM were collected at Riga East Clinical University Hospital (Riga, Latvia) from June 2014 to June 2016. Bone lesions detected by radiography, CT scans, MRI, and PET/CT were divided into degrees from 0 to 3 (0 — no bone involvement, 1 — ≤ 3 bone lesions, 2 — ≥ 3 bone lesions, 3 — fracture). Staging was performed applying Durie/Salmon (DS) and International Staging System classifications. Progressive disease was defined as development of one or more new bone lesions. The levels of bone metabolic markers β-isomerized C-terminal telopeptide of collagen type I (β-CTX) and bone-specific alkaline phosphatase (bALP) were monitored regularly in the year. Results: Bone lesions were found in 86 (69%) patients. From these 6 (4%) patients had 1st degree, 11 (9%) had 2nd degree and 69 (56%) had 3rd degree bone lesions. Level of the bone resorption marker β-CTX in the control group was 0.41 ng/ml, which is lower than in MM patients (p 0.05). However, β-CTX was found to be an excellent diagnostic marker for MM (AUC 0.91; 95% confidence interval, 0.88–0.94; p < 0.001). Conclusions: Patients with MM and bone lesions have increased value of bone resorption marker β-CTX. There is a correlation between bone resorption marker and degree of bone lesions. Changes in β-CTX levels may be used to monitor the effectiveness of myeloma treatment

Longitudinal spin-relaxation in nitrogen-vacancy centers in electron irradiated diamond

We present systematic measurements of longitudinal relaxation rates ($1/T_1$) of spin polarization in the ground state of the nitrogen-vacancy (NV$^-$) color center in synthetic diamond as a function of NV$^-$ concentration and magnetic field $B$. NV$^-$ centers were created by irradiating a Type 1b single-crystal diamond along the [100] axis with 200 keV electrons from a transmission electron microscope with varying doses to achieve spots of different NV$^-$ center concentrations. Values of ($1/T_1$) were measured for each spot as a function of $B$.Comment: 4 pages, 8 figure

Solar retinopathy: a new setting of red, green, and blue channels

PURPOSE: To introduce a new color imaging technique using improved settings of red, green, and blue channels for improved delineation of retinal damage in patients with solar retinopathy. METHODS: A retrospective case series of patients with poor vision secondary to solar retinopathy were analyzed. All patients underwent visual acuity, refraction, and dilated fundus examination. A spectral domain–optical coherence tomography of the macula and color fundus imaging using optimized red, green, and blue color setting was performed. Patients were reviewed over a 6-month period. The data were analyzed for statistical significance using an independent t test and a receiver operating characteristic curve. RESULTS: In total, 20 eyes of 10 patients were included between 2009 and 2017. The mean age was 24.9 ± 18.1 years. Best corrected visual acuity at first consultation was 0.78 ± 0.11 and after 6 months was 0.83 ± 0.09. Spectral domain–optical coherence tomography demonstrated retinal abnormalities at the myoid zone, ellipsoid zone, and the outer segment of photoreceptors. Receiver operating characteristic curve analysis showed an improving effect (area under the curve = 0.62; 95% confidence interval = 0.42–0.79). The color channels parameters, which improve visualization of the lesions were found to be 67-0.98-255 for the R-guided setting, 19-0.63-121 for the B-guided setting, and 7-1.00-129 for the G-guided setting. The ideal red, green, and blue setting was in 24-0.82-229. CONCLUSIONS: The use of a new setting of red, green, and blue channels could improve the diagnosis and monitoring of solar retinopathy, hence improving patient care

Nanometric moiré stripes on the surface of Bi2Se3 topological insulator

Mismatch between adjacent atomic layers in low-dimensional materials, generating moiré patterns, has recently emerged as a suitable method to tune electronic properties by inducing strong electron correlations and generating novel phenomena. Beyond graphene, van der Waals structures such as three-dimensional (3D) topological insulators (TIs) appear as ideal candidates for the study of these phenomena due to the weak coupling between layers. Here we discover and investigate the origin of 1D moiré stripes on the surface of Bi2Se3TI thin films and nanobelts. Scanning tunneling microscopy and high-resolution transmission electron microscopy reveal a unidirectional strained top layer, in the range 14-25%, with respect to the relaxed bulk structure, which cannot be ascribed to the mismatch with the substrate lattice but rather to strain induced by a specific growth mechanism. The 1D stripes are characterized by a spatial modulation of the local density of states, which is strongly enhanced compared to the bulk system. Density functional theory calculations confirm the experimental findings, showing that the TI surface Dirac cone is preserved in the 1D moiré stripes, as expected from the topology, though with a heavily renormalized Fermi velocity that also changes between the top and valley of the stripes. The strongly enhanced density of surface states in the TI 1D moiré superstructure can be instrumental in promoting strong correlations in the topological surface states, which can be responsible for surface magnetism and topological superconductivity

Surface Modifications by Field Induced Diffusion

By applying a voltage pulse to a scanning tunneling microscope tip the surface under the tip will be modified. We have in this paper taken a closer look at the model of electric field induced surface diffusion of adatoms including the van der Waals force as a contribution in formations of a mound on a surface. The dipole moment of an adatom is the sum of the surface induced dipole moment (which is constant) and the dipole moment due to electric field polarisation which depends on the strength and polarity of the electric field. The electric field is analytically modelled by a point charge over an infinite conducting flat surface. From this we calculate the force that cause adatoms to migrate. The calculated force is small for voltage used, typical 1 pN, but due to thermal vibration adatoms are hopping on the surface and even a small net force can be significant in the drift of adatoms. In this way we obtain a novel formula for a polarity dependent threshold voltage for mound formation on the surface for positive tip. Knowing the voltage of the pulse we then can calculate the radius of the formed mound. A threshold electric field for mound formation of about 2 V/nm is calculated. In addition, we found that van der Waals force is of importance for shorter distances and its contribution to the radial force on the adatoms has to be considered for distances smaller than 1.5 nm for commonly used voltages

Electrical Sintering of Silver Nanoparticle Ink Studied by In-Situ TEM Probing

Metallic nanoparticle inks are used for printed electronics, but to reach acceptable conductivity the structures need to be sintered, usually using a furnace. Recently, sintering by direct resistive heating has been demonstrated. For a microscopic understanding of this Joule heating sintering method, we studied the entire process in real time inside a transmission electron microscope equipped with a movable electrical probe. We found an onset of Joule heating induced sintering and coalescence of nanoparticles at power levels of 0.1–10 mW/m3. In addition, a carbonization of the organic shells that stabilize the nanoparticles were found, with a conductivity of 4 105 Sm−1

Optical systems for non-invasive cardiovascular biosensing

ABSTRACT Three portable prototype devices for cardiovascular biosensing based on reflection-type photoplethysmography (PPG) principle have been designed and clinically tested. The single-channel PPG finger sensor provides real-time measurements with fast calculation of the mean single-period PPG signal shape (&quot;cardiovascular fingerprint&quot;, potentially useful for recognition). The dual-channel PPG system gives additional possibility to monitor on-line the arterial pulse wave transit time and its responses to physical exercises. The four-channel PPG system proved to be applicable for fast detection of cardiovascular pathologies, e.g. arterial occlusions in extremities. Design principles and software algorithms of the regarded devices will be discussed, as well as the results of recent clinical tests