Lanthanide ions (Eu3+, Er3+, Pr3+) as luminescence and charge carrier centers in Sr2TiO4

A series of strontium orthotitanate (Sr₂TiO₄) samples doped with 2% of a mole of europium, praseodymium, and erbium were obtained using the solid-state synthesis method. The X-ray diffraction (XRD) technique confirms the phase purity of all samples and the lack of the influence of dopants at a given concentration on the structure of materials. The optical properties indicate, in the case of Sr₂TiO₄:Eu³⁺, two independent emission (PL) and excitation (PLE) spectra attributed to the Eu³⁺ ions at sites with different symmetries: low - excited at 360 nm and high - excited at 325 nm, while, for Sr₂TiO₄:Er³⁺ and Sr₂TiO₄:Pr³⁺, the emission spectra do not depend on the excitation wavelength. The measurements of X-ray photoemission spectroscopy (XPS) indicate the presence of only one type of charge compensation mechanism, which is based on the creation of strontium vacancies in all cases. This suggests that the different charge compensation mechanisms cannot easily explain the presence of Eu³⁺ at two non-equivalent crystal sites. The photocurrent excitation (PCE) spectroscopy investigations, that have not been reported in the literature so far, show that among all the studied dopants, only Pr³⁺ can promote the electrons to the conduction band and give rise to electron conductivity. The results collected from the PLE and PCE spectra allowed us to find the location of the ground states of lanthanides(II)/(III) in the studied matrix.

Uro-oncology in the era of social distancing: the principles of patient-centered online consultations during the COVID-19 pandemic

Introduction

The COVID-19 pandemic poses significant challenges to healthcare facilities and as per social distancing measures, many consultations are now being carried out via means of telemedicine. As some urologists may not be skilled with remote consultations, there is a need for recommendations on patient-centered online medical counseling.

Material and methods

We have identified eight areas of excellence and defined the principles based on our experience.

Results

A professional setting should be provided, in which the privacy of the patient can be ensured. Accompanying persons should be encouraged into the consultation. Proper introduction could serve not only to verify the personality of the patient, but also to provide them with a sense of confidentiality. The interview should be held in a way to overcome the limitations of non-physical encounters, and pande-mic-specific issues should be taken into consideration. When arranging plans, the physician should judge accordingly in regards to what type of management is inevitable or safe, as well as available at this point; strict follow-up should be arranged. As home isolation may lead to unfavorable changes in lifestyle, this issue should be addressed too. The patient should be guided on how to self-educate. Concluding the visit should be aimed at proper evaluation of the patient's comprehension of the consultation.

Conclusions

It is vital to pursue consistency in providing care to patients. While online counseling may seem challenging, if one adheres to the principles of patient-centered practice, telemedicine may become a valuable tool in maintaining the best-quality care amid the ongoing pandemic.

Ultrafast Formation of a Fermi-Dirac Distributed Electron Gas

Time- and angle-resolved photoelectron spectroscopy with 13 fs temporal resolution is used to follow the different stages in the formation of a Fermi-Dirac distributed electron gas in graphite after absorption of an intense 7 fs laser pulse. Within the first 50 fs after excitation, a sequence of time frames is resolved that are characterized by different energy and momentum exchange processes among the involved photonic, electronic, and phononic degrees of freedom. The results reveal experimentally the complexity of the transition from a nascent nonthermal towards a thermal electron distribution due to the different timescales associated with the involved interaction processes.

Harnessing New Media Tools in Patient Information

New media in patient information: without a visual component, your message might not be heard.

Biomarkers in Urachal Cancer and Adenocarcinomas in the Bladder: A Comprehensive Review Supplemented by Own Data

Urachal cancer (UrC) is a rare but aggressive cancer. Due to overlapping histomorphology, discrimination of urachal from primary bladder adenocarcinomas (PBAC) and adenocarcinomas secondarily involving the bladder (particularly colorectal adenocarcinomas, CRC) can be challenging. Therefore, we aimed to give an overview of helpful (immunohistochemical) biomarkers and clinicopathological factors in addition to survival analyses and included institutional data from 12 urachal adenocarcinomas. A PubMed search yielded 319 suitable studies since 1930 in the English literature with 1984 cases of UrC including 1834 adenocarcinomas (92%) and 150 nonadenocarcinomas (8%). UrC was more common in men (63%), showed a median age at diagnosis of 50.8 years and a median tumor size of 6.0 cm. No associations were noted for overall survival and progression-free survival (PFS) and clinicopathological factors beside a favorable PFS in male patients (p = 0.047). The immunohistochemical markers found to be potentially helpful in the differential diagnostic situation are AMACR and CK34βE12 (UrC versus CRC and PBAC), CK7, β-Catenin and CD15 (UrC and PBAC versus CRC), and CEA and GATA3 (UrC and CRC versus PBAC). Serum markers like CEA, CA19-9 and CA125 might additionally be useful in the follow-up and monitoring of UrC.

Spectroscopic properties and location of the Tb3+ and Eu3+ energy levels in Y2O2S under high hydrostatic pressure

In this contribution, an extensive spectroscopic study of Y₂O₂S doped with Eu³⁺ and Tb³⁺ is presented.

Structural requirements of steroidal agonists of transient receptor potential melastatin 3 (TRPM3) cation channels

Background and Purpose

Transient receptor potential melastatin 3 (TRPM3) proteins form non-selective but calcium-permeable membrane channels, rapidly activated by extracellular application of the steroid pregnenolone sulphate and the dihydropyridine nifedipine. Our aim was to characterize the steroid binding site by analysing the structural chemical requirements for TRPM3 activation.

Experimental Approach

Whole-cell patch-clamp recordings and measurements of intracellular calcium concentrations were performed on HEK293 cells transfected with TRPM3 (or untransfected controls) during superfusion with pharmacological substances.

Key Results

Pregnenolone sulphate and nifedipine activated TRPM3 channels supra-additively over a wide concentration range. Other dihydropyridines inhibited TRPM3 channels. The natural enantiomer of pregnenolone sulphate was more efficient in activating TRPM3 channels than its synthetic mirror image. However, both enantiomers exerted very similar inhibitory effects on proton-activated outwardly rectifying anion channels. Epiallopregnanolone sulphate activated TRPM3 almost equally as well as pregnenolone sulphate. Exchanging the sulphate for other chemical moieties showed that a negative charge at this position is required for activating TRPM3 channels.

Conclusions and Implications

Our data demonstrate that nifedipine and pregnenolone sulphate act at different binding sites when activating TRPM3. The latter activates TRPM3 by binding to a chiral and thus proteinaceous binding site, as inferred from the differential effects of the enantiomers. The double bond between position C5 and C6 of pregnenolone sulphate is not strictly necessary for the activation of TRPM3 channels, but a negative charge at position C3 of the steroid is highly important. These results provide a solid basis for understanding mechanistically the rapid chemical activation of TRPM3 channels.

High pressure luminescence spectra of CaMoO4:Ln3+ (Ln = Pr, Tb)

Photoluminescence spectra and luminescence kinetics of pure CaMoO(4) and CaMoO(4) doped with Ln(3+) (Ln = Pr or Tb) are presented. The spectra were obtained at high hydrostatic pressure up to 240 kbar applied in a diamond anvil cell. At ambient pressure undoped and doped samples exhibit a broad band emission extending between 380 and 700 nm with a maximum at 520 nm attributed to the MoO(4)(2-) luminescence. CaMoO(4) doped with Pr(3+) or Tb(3+) additionally yields narrow emission lines related to f-f transitions. The undoped CaMoO(4) crystal was characterized by a strong MoO(4)(2-) emission up to 240 kbar. In the cases of CaMoO(4):Pr(3+) and CaMoO(4):Tb(3+), high hydrostatic pressure caused quenching of Pr(3+) and Tb(3+) emission, and this effect was accompanied by a strong shortening of the luminescence lifetime. In doped samples, CaMoO(4):Pr(3+) and CaMoO(4):Tb(3+), quenching of the emission band attributed to MoO(4)(2-) was also observed, and at pressure above 130 kbar this luminescence was totally quenched. The effects mentioned above were related to the influence of the praseodymium (terbium) trapped exciton PTE (ITE-impurity trapped exciton) on the efficiency of the Pr(3+) (Tb(3+)) and MoO(4)(2-) emissions.

Effects of rosuvastatin on cardiovascular morphology and function in an ApoE-knockout mouse model of atherosclerosis

This study investigated the effects of rosuvastatin on plaque progression and in vivo coronary artery function in apolipoprotein E-knockout (ApoE-KO) mice, using noninvasive high-resolution ultrasound techniques. Eight-week-old male ApoE-KO mice (n = 20) were fed a high-fat diet with or without rosuvastatin (10 micromol.kg(-1).day(-1)) for 16 wk. When compared with control, rosuvastatin reduced total cholesterol levels (P < 0.05) and caused significant retardation of lesion progression in the brachiocephalic artery, as visualized in vivo using an ultrasound biomicroscope (P < 0.05). Histological analysis confirmed the reduction of brachiocephalic atherosclerosis and also revealed an increase in collagen content in the statin-treated group (P < 0.05). Coronary volumetric flow was measured by simultaneous recording of Doppler velocity signals and left coronary artery morphology before and during adenosine infusion. The hyperemic flow in response to adenosine was significantly greater in left coronary artery following 16 wk of rosuvastatin treatment (P < 0.001), whereas the baseline flow was similar in both groups. In conclusion, rosuvastatin reduced brachiocephalic artery atherosclerotic plaques in ApoE-KO mice. Coronary artery function assessed using recently developed in vivo ultrasound-based protocols, also improved.

Human TIEG2/KLF11 induces oligodendroglial cell death by downregulation of Bcl-XL expression

TGF-beta-induced apoptosis is essential for embryonic development and mainteanance of adult tissues. Impairment of the apoptotic pathway, regulated by TGF-beta, plays a center role in tumorigenesis and manifestations of different diseases. TIEG2/KLF11 is a recently identified human TGF-beta-inducible zinc finger protein belonging to the family of Sp1/KLF-like transcription factors. In human and murine tissues it has been shown that TIEG1 and TIEG2 induce apoptosis and inhibit cell growth. Since TGF-beta and Tieg1 are able to induce apoptosis in the oligodendroglial cell line OLI-neu, we analysed the ability of TIEG2 to mimic the effects observed after treatment with TGF-beta and overexpression of Tieg1. Herein we report that TIEG2 induces Caspase3-dependent apoptosis in murine OLI-neu cells. Furthermore, we could demonstrate that TIEG2 decreases the levels of the anti-apoptotic protein Bcl-X(L) and inhibits transcription driven by the Bcl-X(L) promoter. These data suggest that TIEG2 serves as a downstream mediator of TGF-beta, bridging TGF-beta-dependent signaling to the intracellular pathway of apoptosis.

The isolation and characterisation of antiplatelet antibodies

The isolation and characterisation of antiplatelet antibodies in autoimmune thrombocytopenia purpura patients (ITP) is described. Autoimmune thrombocytopenia purpura is an autoimmune disease, clinically defined by low platelet counts, normal or increased megakaryocytopoiesis and antiplatelet antibodies in serum. This study used phage display to isolate Fab antiplatelet antibodies to study the structure-function relationships of pathogenic antibodies in ITP. Out of six randomly selected colonies, four colonies reacted strongly with whole platelets in enzyme-linked immunosorbent assay (ELISA). Sequence analysis showed that all four colonies had the same DNA sequence and were the same antibody. Results of Western blotting against non-reduced human platelet lysate showed that the Fab reacted with platelet proteins with apparent molecular weights of 116, 92 and 39 kD. Furthermore, Western blotting assay against purified membrane glycoprotein IIIa demonstrated reactivity against a band with a molecular weight of 92 kD. Results from Western blotting against platelet lysate and pure platelet glycoprotein confirmed the Fab fragment recognised the platelet glycoprotein IIIa. Three out of the four phage colonies produced soluble Fab, which demonstrated reactivity against platelet autoantigens in ELISA. Further sequence analysis showed that the Fab was somatically mutated suggesting antigen drive and therefore T-cell assistance was important in the development of this antibody. One of the somatic mutations introduced an RSD amino acid sequence in the complementary determining region 1 (CDR1) of the light chain, which may mimic the RGD motif of fibrinogen which binds integrin GPIIb/IIIa. This raises the possibility that somatic mutation and antigen drive have produced a pathogenic autoantibody.

Balance of pro-apoptotic transforming growth factor-β and anti-apoptotic insulin effects in the control of cell death in the postnatal mouse retina

Transforming growth factor (TGF)-beta and insulin display opposite effects in regulating programmed cell death during vertebrate retina development; the former induces apoptosis while the latter prevents it. In the present study we investigated coordinated actions of TGF-beta and insulin in an organotypic culture system of early postnatal mouse retina. Addition of exogenous TGF-beta resulted in a significant increase in cell death whereas exogenous insulin attenuated apoptosis and was capable of blocking TGF-beta-induced apoptosis. This effect appeared to be modulated via insulin-induced transcriptional down-regulation of TGF-beta receptor II levels. The analysis of downstream signalling molecules also revealed opposite effects of both factors; insulin provided survival signalling by increasing the level of anti-apoptotic Bcl-2 protein expression and phosphorylation and down-regulating caspase 3 activity whereas pro-apoptotic TGF-beta signalling reduced Bcl-2 mRNA levels and Bcl-2 phosphorylation and induced the expression of TGF-induced immediate-early gene (TIEG), a Krüppel-like zinc-finger transcription factor, mimicking TGF-beta activity.

The role of somatic mutation in determining the affinity of anti-DNA antibodies

Combinatorial antibody libraries were constructed from the spleen of a patient with concomitant systemic lupus erythematosus and idiopathic thrombocytopenia. Following selection of the libraries with DNA, a panel of 15 anti-DNA Fabs was isolated. Sequence analysis of these antibodies coupled with measurements of their affinities for ss- and dsDNA were used to investigate the role of somatic mutation in affinity maturation of the anti-DNA response. Examination of the germline genes used by these Fabs supports previous studies that suggest there is no restriction of the gene usage in the anti-DNA response. However, data are presented indicating that VH3 genes and the A27 V(kappa) paired with the J(kappa)1 may be over-expressed in the anti-DNA repertoire. Analysis of the role of somatic mutation in increasing affinity for DNA indicates that affinity maturation has occurred and suggests that the CDR1 and CDR2 of the heavy chain are of importance in this process.

Multicolor spectral karyotype analysis of a transplantable human ileal carcinoid

In this report we present the results of a combined cytogenetic and multicolor spectral karyotype (SKY) analysis of a transplantable human ileal carcinoid (GOT1). By using SKY it was possible to identify the origin and organization of all clonal marker chromosomes and to identify cryptic translocations not detectable by conventional chromosome banding. The stemline karyotype of low passage GOT1 cells was interpreted as 43,XX, der(1)del(1)(?), inv(2)(p25q13), del(3)(p21), del(5)(q13q31), del(6)(q13), -9, -13, -15, del(16) (q22). Analysis of the GOT1 cells after about 2.5 years of propagation in nude mice allowed us to follow the in vivo progression of this tumor. Relatively few additional rearrangements had occurred during this period, indicating that the GOT1 cells are genetically stable. Most of the abnormalities detected result in loss of whole or parts of chromosomes, suggesting that loss of multiple chromosomal regions, presumably containing tumor suppressor genes, might be important genetic events in ileal carcinoids.

The identification of endothelial cell autoantigens

The identity of many endothelial cell autoantigens remains unclear. This study has used human monoclonal anti-endothelial cell autoantibodies isolated from patients with SLE to identify endothelial autoantigens. Thirteen antibodies reactive with endothelial cell membrane preparations were isolated and cloned, one of which has previously been demonstrated to be pro-inflammatory. Western blotting demonstrates that these antibodies recognize a variety of proteins in endothelial cell membrane preparations. Further characterization of five antibodies by cDNA library screening, immunofluorescence and Western blotting proves that two of these antibodies recognized the cytoskeletal proteins tubulin and vimentin. A further antibody identified a clone derived from human collagenase, an identification supported by Western blotting. The multiple clones selected by other antibodies are not compatible with the molecular weight of the antigen recognized in Western blotting studies. This study has clearly identified two endothelial cell autoantigens present in membrane preparations and provides strong evidence as to the identity of a third.

Expression and mutation patterns of p53 in benign and malignant salivary gland tumors

The expression and mutation patterns of p53 were studied in a series of 68 benign pleomorphic adenomas and 237 malignant salivary gland tumors. p53 overexpression (nuclear staining exceeding 10%) was detected in 20% of the malignant salivary gland tumors, with the highest prevalence observed in polymorphous low grade adenocarcinoma, squamous cell carcinoma, and carcinoma ex pleomorphic adenoma and the lowest in adenoid cystic carcinoma and acinic cell carcinoma. In contrast, none of the 68 benign pleomorphic adenomas had nuclear staining exceeding 10%. SSCP and nucleotide sequence analysis of exons 4 to 9 of p53 in 19 malignant tumors revealed 9 mutations in 7 tumors. Our findings indicate that p53 may be a useful marker to help discriminate between benign and malignant salivary gland tumors.

Density and molecular epidemiology of Aspergillus in air and relationship to outbreaks of Aspergillus infection

After five patients were diagnosed with nosocomial invasive aspergillosis caused by Aspergillus fumigatus and A. flavus, a 14-month surveillance program for pathogenic and nonpathogenic fungal conidia in the air within and outside the University Hospital in Rotterdam (The Netherlands) was begun. A. fumigatus isolates obtained from the Department of Hematology were studied for genetic relatedness by randomly amplified polymorphic DNA (RAPD) analysis. This was repeated with A. fumigatus isolates contaminating culture media in the microbiology laboratory. The density of the conidia of nonpathogenic fungi in the outside air showed a seasonal variation: higher densities were measured during the summer, while lower densities were determined during the fall and winter. Hardly any variation was found in the numbers of Aspergillus conidia. We found decreasing numbers of conidia when comparing air from outside the hospital to that inside the hospital and when comparing open areas within the hospital to the closed department of hematology. The increase in the number of patients with invasive aspergillosis could not be explained by an increase in the number of Aspergillus conidia in the outside air. The short-term presence of A. flavus can only be explained by the presence of a point source, which was probably patient related. Genotyping A. fumigatus isolates from the department of hematology showed that clonally related isolates were persistently present for more than 1 year. Clinical isolates of A. fumigatus obtained during the outbreak period were different from these persistent clones. A. fumigatus isolates contaminating culture media were all genotypically identical, indicating a causative point source. Knowledge of the epidemiology of Aspergillus species is necessary for the development of strategies to prevent invasive aspergillosis. RAPD fingerprinting of Aspergillus isolates can help to determine the cause of an outbreak of invasive aspergillosis.

Fluorescence in situ hybridization mapping of breakpoints in pleomorphic adenomas with 8q12-13 abnormalities identifies a subgroup of tumors without PLAG1 involvement

Recently, we identified the PLAG1 gene as the target gene in pleomorphic adenomas with chromosome abnormalities involving 8q12. The majority of breakpoints were shown to reside within the 5' noncoding region of the gene. We now report three pleomorphic adenomas with breakpoints located distal to PLAG1 in band 8q13. These tumors had the following chromosome 8 abnormalities: ins(8;12)(q12-13;q14q15), t(8;12)(q13;q15), and t(6;8)(p21.3-22;q13). Fluorescence in situ hybridization mapping of the chromosome 8 breakpoints revealed a yeast artificial chromosome clone spanning the breakpoints in two tumors. In none of the cases was PLAG1 activated and/or disrupted. Three candidate genes, N8, HMGIC, and HMGIY, were analyzed for rearrangements and/or abnormal expression by using reverse transcriptase-polymerase chain reaction, rapid amplification of 3' cDNA ends, and Northern blot analyses.

Does the CDR3 of the heavy chain determine the specificity of autoantibodies in systemic lupus erythematosus?

Many factors are involved in the recognition of autoantigens by autoanti-bodies, including the use of specific germline genes, the sequence and structure of the CDR3 of the heavy chain, somatic mutation and selective heavy and light chain pairing. However, the relative importance of these factors remainsunclear. This study reports the results of sequence analysis of two anti-endothelial cell antibodies that recognise the same antigen. Sequence analysis of these antibodies shows that they use the same heavy chain germline genes as two anti-DNA antibodies but differ significantly in the sequence of the CDR3. Furthermore, one of the antibodies uses a light chain germline gene combination that has been reported for three anti-DNA antibodies. One of these antibodies shows significant mutation in the CDR2 of the heavy chain. Peptide analysis suggests that the differences between these anti-DNA and anti-endothelial cell antibodies result in consistent structural differences that may reflect the nature of the antigen recognised.

[Frequency of human papillomavirus-herpes simplex-cytomegalovirus and Chlamydia trachomatis infection in genital tracts of sexual partners]

OBJECTIVES

Much attention is given nowadays to the role of Human Papillomavirus, Herpes simplex virus, Cytomegalovirus, and Chlamydia trachomatis--infections in cervical carcinogenesis. Cytomegalovirus, Herpes simplex and Chlamydia trachomatis are now thought to be teratogenic to humans.

DESIGN

We investigated the prevalence of HPV, HSV, CMV and Chlamydia trachomatis in genital tracts of sexual partners.

MATERIALS AND METHODS

90 sexual partners were qualified for the research. Examination smears were taken with the dacron swab from the vaginal part of the uterine cervix, cervical canal, the lower vagina from women and from fossa navicularis penis in men. In the group of 67 men we have investigated semen as well. HPV, HSV, CMV and Chlamydia trachomatis were identified using PCR (Polymerse Chain Reaction)--method.

RESULTS AND CONCLUSIONS

In 48% of investigated sexual partners we proved the presence of Human Papillomavirus, in 2.2% of women and 2.9% of men--Cytomegalovirus and in 11.1% of women and 14.9% of men--Chlamydia trachomatis. In the investigated biological material we did not find any HSV infection.

Reduced beta-endorphin secretion in young patients with mild essential hypertension at rest and during exercise

Evidence suggests that altered central adrenergic and opioidergic activities are involved in the elevated blood pressure of patients with essential hypertension. In the present study plasma concentrations of the opioid peptide beta-endorphin were significantly lower at rest in young subjects with essential hypertension and high plasma noradrenaline (n = 9) than in normotensive controls (n = 13, P less than 0.05). After bicycle exercise the beta-endorphin of both groups increased comparably, the percentage increase being greater in essential hypertensives than in controls. Treatment with clonidine for 14 days normalized low beta-endorphin, high plasma noradrenaline and high blood pressure in essential hypertensives at rest, but had no effect in controls. After bicycle exercise clonidine induced a threefold greater increase in beta-endorphin in controls than in essential hypertensives. The results point to a reduced endorphinergic activity in essential hypertensives, both at rest and during exercise, which can be normalized by central alpha 2-agonism at rest only. The results may indicate altered interactions between central adrenergic and opioidergic receptor systems, which could contribute to high blood pressure in essential hypertensives.