Near-IR Luminescence of Rare-Earth Ions (Er3+, Pr3+, Ho3+, Tm3+) in Titanate–Germanate Glasses under Excitation of Yb3+

Inorganic glasses co-doped with rare-earth ions have a key potential application value in the field of optical communications. In this paper, we have fabricated and then characterized multicomponent TiO₂-modified germanate glasses co-doped with Yb³⁺/Ln³⁺ (Ln = Pr, Er, Tm, Ho) with excellent spectroscopic properties. Glass systems were directly excited at 980 nm (the ²F_7/2 → ²F_5/2 transition of Yb³⁺). We demonstrated that the introduction of TiO₂ is a promising option to significantly enhance the main near-infrared luminescence bands located at the optical telecommunication window at 1.3 μm (Pr³⁺: ¹G₄ → ³H₅), 1.5 μm (Er³⁺: ⁴I_13/2 → ⁴I_15/2), 1.8 μm (Tm³⁺: ³F₄ → ³H₆) and 2.0 μm (Ho³⁺: ⁵I₇ → ⁷I₈). Based on the lifetime values, the energy transfer efficiencies (η_ET) were estimated. The values of η_ET are changed from 31% for Yb³⁺/Ho³⁺ glass to nearly 53% for Yb³⁺/Pr³⁺ glass. The investigations show that obtained titanate–germanate glass is an interesting type of special glasses integrating luminescence properties and spectroscopic parameters, which may be a promising candidate for application in laser sources emitting radiation and broadband tunable amplifiers operating in the near-infrared range.     

Application of array comparative genomic hybridization (aCGH) for identification of chromosomal aberrations in the recurrent pregnancy loss

Spontaneous abortion occurs in 8–20% of recognized pregnancies and usually takes place in the first trimester (7–11 weeks). There are many causes of pregnancy loss, but the most important (about 75%) is the presence of chromosomal aberrations. We present the results of oligonucleotide array application in a cohort of 62 miscarriage cases. The inclusion criteria for the study were the loss after 8th week of pregnancy and the appearance of recurrent miscarriages. DNA was extracted from trophoblast or fetal skin fibroblasts. In the 62 tested materials from recurrent miscarriages, the detection rate was 56.5% (35/62). The most commonly found were aneuploidies (65%) (chromosomal trisomy 14, 16, 18, 21, and 22), Turner syndrome, and triploidy (17.1%). Other chromosomal abnormalities included pathogenic and likely pathogenic structural aberrations: 1) pathogenic: deletion 7p22.3p12.3 and duplication 9p24.3p13.2 inherited from the normal father, deletion 3q13.31q22.2 and deletion 3q22.3q23 of unknown inheritance and duplication of 17p12 inherited from father with foot malformation; 2) likely pathogenic variants: deletion 17p13.1 inherited from normal mother, deletion 5q14.3 of unknown inheritance and de novo deletion 1q21.1q21.2. Among these aberrations, six CNVs (copy number variants) were responsible for the miscarriage: deletion 7p22.3p12.3 and duplication 9p24.3p13.2, deletion 3q13.31q22.2 and deletion 3q22.3q23, and deletion 17p13.1 and deletion 1q21.1q21.2. Other two findings were classified as incidental findings (deletion 5q14.3 and 17p12 duplication). Our research shows that 17% of the aberrations (6/35 abnormal results) that cannot be identified by the routine kariotype analysis are structural aberrations containing genes important for fetal development, the mutations of which may cause spontaneous abortion.     

Coronary flow reserve and exercise capacity in hypertrophic cardiomyopathy

Summary The aim of this study was to evaluate the relation of coronary flow velocity (CFV) and coronary flow reserve (CFR) to exercise capacity in ten verapamil-treated patients with hypertrophic cardiomyopathy (HC). Using Doppler transesophageal echocardiography, we assessed diastolic CFV in the proximal left anterior descending coronary artery at baseline and after administering 0.56 mg/kg intravenous dipyridamole. The CFR was calculated as the postdipyridamole/baseline diastolic CFV ratio. A maximal symptom-limited exercise treadmill test was performed according to a modified Bruce protocol and the exercise capacity was expressed as metabolic equivalents. The mean value for baseline diastolic CFV was 59 ± 27cm/s; this increased after dipyridamole to 134 ± 57cm/s. The CFR was 2.37 ± 0.67. Baseline diastolic CFV correlated negatively with both exercise duration (r = –0.69;P < 0.05) and value for metabolic equivalents (r = –0.70;P < 0.05). CFR was weakly and non-significantly related to exercise duration (r = 0.40;P > 0.05) and to the value for metabolic equivalents (r = 0.32;P > 0.05). Shortening of exercise time and decreasing metabolic equivalents were correlated with increased baseline diastolic CFV. Dipyridamole-assessed CFR, was weakly related to parameters of exercise capacity.     

Reactive Sintering of Dysprosium-Iron Garnet via a Perovskite-Hematite Solid State Reaction and Physical Properties of the Material

In this paper, we report on a successful synthesis of dysprosium iron garnet Dy₃Fe₅O₁₂ (DyIG) by a reactive synthesis method involving dysprosium iron perovskite and hematite. Phase formation was traced using dilatometry, and XRD measurements attested to the formation of the desired structure. Samples with relative density close to 97% were fabricated. The samples were characterized using vibrating sample magnetometry, dielectric spectroscopy, and UV-Vis-NIR spectroscopy. Magnetic properties were probed in temperatures between 80 and 700 K with a maximum applied field of 1 kOe. The measurements revealed several effects: the compensation of magnetic moments at a certain temperature, the inversion of the magnetocaloric effect, and the ability to measure the Curie temperature of the material. Activation energy was determined from UV-Vis-NIR and dielectric spectroscopy measurements. Characteristic magnetic temperatures and activation energy values of the samples were similar to bulk DyIG obtained using other methods.     

An Assessment of Serum Selenium Concentration in Women with Endometrial Cancer

Background: Numerous studies have shown a relationship between low serum selenium levels and an increased risk of developing cancer. Methods: A total of 306 women participated in the study: 153 patients diagnosed with endometrial cancer and 153 healthy women who were matched, in terms of birth year (+/−3 years), to the patients from the study group. The quantitative measurement of selenium content in the collected blood samples was performed using a mass spectrometer with excitation in inductively coupled plasma. In order to determine the relationship between the risk factors and the incidence of endometrial cancer, analyses based on single- and multi-factor conditional logistic regression models were performed. Results: The mean concentration of selenium was lower in patients with endometrial cancer than in healthy controls (60.63 µg/L (0.77 µmol/L) vs. 78.74 µg/L (0.99 µmol/L), respectively). When compared in quartiles, a significant association of lower selenium concentration with the incidence of endometrial cancer was recorded. The highest OR was observed in the first and second quartiles (OR-22.0, p-value < 0.001; medium selenium level 46.95 µg/L (0.59 µmol/L), and OR-5.94; p-value < 0.001; medium selenium level 63.60 µg/L (0.80 µmol/L), respectively). Conclusion: A strong correlation between the level of selenium in the blood serum and the risk of endometrial cancer indicates that patients with low levels should be a candidate group requiring appropriate preventive examinations. Further research on a larger group of patients is required.     

Intrasalivary Thymic Carcinoma: A Case Report and Literature Review

Ectopic thymic carcinomas are rarely diagnosed in the thyroid gland, let alone in extrathyroid tissues. In the currently available literature, only five cases of extrathyroidal malignancies with thymic differentiation have been reported as arising in the major salivary glands. A 69-year-old female presented with a slow-growing palpable mass in the left parotid gland. Fine needle aspiration biopsy suggested metastatic cancer, whereas core needle biopsy revealed high-grade squamous cell carcinoma. The patient underwent left radical parotidectomy with selective ipsilateral lymph node dissection and subsequent radiation therapy. The surgical specimen was taken for histopathological examination. Microscopically, the tumor resembled thymic carcinoma. It was composed of large nests of squamoid cells with smooth contours, focally with a syncytial growth pattern, and accompanied by abundant lymphocytes with reactive lymphoid follicles. This appearance resembled a micronodular thymic carcinoma with lymphoid hyperplasia. Moreover, the tumor displayed expression of squamous markers (p40 and p63) and markers of thymic carcinoma (CD5 and CD117). Therefore, the final diagnosis of intrasalivary thymic carcinoma was rendered. The molecular analysis including next-generation sequencing demonstrated no variants of the strong, potential, or unknown clinical significance. The patient remains disease-free at 1-year follow-up. In the current case, we comprehensively present a clinical, microscopic, molecular, and radiological picture of CD5-positive squamous cell carcinoma of the parotid. We postulate that similar cases should be designated as intrasalivary thymic carcinoma analogically to similar thyroid tumors. Our case and the limited literature data indicate they should be distinguished from conventional squamous cell carcinoma of major salivary glands due to their rather favorable prognosis.     

Evaluation of Effective Mass in InGaAsN/GaAs Quantum Wells Using Transient Spectroscopy

Transient spectroscopies are sensitive to charge carriers released from trapping centres in semiconducting devices. Even though these spectroscopies are mostly applied to reveal defects causing states that are localised in the energy gap, these methods also sense-charge from quantum wells in heterostructures. However, proper evaluation of material response to external stimuli requires knowledge of material properties such as electron effective mass in complex structures. Here we propose a method for precise evaluation of effective mass in quantum well heterostructures. The infinite well model is successfully applied to the InGaAsN/GaAs quantum well structure and used to evaluate electron effective mass in the conduction and valence bands. The effective mass m/m₀ of charges from the conduction band was 0.093 ± 0.006, while the charges from the conduction band exhibited an effective mass of 0.122 ± 0.018.     

Infrared Stimulated Luminescence of Ce3+ Doped YAG Crystals

In this study, the infrared optically stimulated luminescence (IRSL) of single crystals of Ce³⁺ doped yttrium aluminum garnet (YAG) was investigated for the first time. It was found that infrared stimulation of these crystals, following previous exposure to beta radiation, produces a strong luminescence signal. The highest luminescence efficiency was exhibited by the YAG crystal with 0.1% of Ce. With this crystal, it was possible to measure as low doses as 0.1 mGy. Moreover, IRSL is mainly related to the TL peak at a relatively high temperature of c.a. 175 °C, which leads to quite good stability of the signal in time. These properties create good prospects for potential applications of YAG:Ce in dosimetric radiation measurements     

Evaluation of Clinical Biomarkers Related to CD4 Recovery in HIV-Infected Patients—5-Year Observation

Human Immunodeficiency Virus infection leads to the impairment of immune system function. Even long-term antiretroviral therapy uncommonly leads to the normalization of CD4 count and CD4:CD8 ratio. The aim of this study was to evaluate possible clinical biomarkers which may be related to CD4 and CD4:CD8 ratio recovery among HIV-infected patients with long-term antiretroviral therapy. The study included 68 HIV-infected patients undergoing sustained antiretroviral treatment for a minimum of 5 years. Clinical biomarkers such as age, gender, advancement of HIV infection, coinfections, comorbidities and applied ART regimens were analyzed in relation to the rates of CD4 and CD4:CD8 increase and normalization rates. The results showed that higher rates of CD4 normalization are associated with younger age (p = 0.034), higher CD4 count (p = 0.034) and starting the therapy during acute HIV infection (p = 0.012). Higher rates of CD4:CD8 ratio normalization are correlated with higher CD4 cell count (p = 0.022), high HIV viral load (p = 0.006) and acute HIV infection (p = 0.013). We did not observe statistically significant differences in CD4 recovery depending on gender, HCV/HBV coinfections, comorbidities and opportunistic infections. The obtained results advocate for current recommendations of introducing antiretroviral therapy as soon as possible, preferably during acute HIV infection, since it increases the chances of sufficient immune reconstruction.