Robust Dipolar Layers between Organic Semiconductors and Silver for Energy-Level Alignment.

The interface between a metal electrode and an organic semiconductor (OS) layer has a defining role in the properties of the resulting device. To obtain the desired performance, interlayers are introduced to modify the adhesion and growth of OS and enhance the efficiency of charge transport through the interface. However, the employed interlayers face common challenges, including a lack of electric dipoles to tune the mutual position of energy levels, being too thick for efficient electronic transport, or being prone to intermixing with subsequently deposited OS layers. Here, we show that monolayers of 1,3,5-tris(4-carboxyphenyl)benzene (BTB) with fully deprotonated carboxyl groups on silver substrates form a compact layer resistant to intermixing while capable of mediating energy-level alignment and showing a large insensitivity to substrate termination. Employing a combination of surface-sensitive techniques, i.e., low-energy electron microscopy and diffraction, X-ray photoelectron spectroscopy, and scanning tunneling microscopy, we have comprehensively characterized the compact layer and proven its robustness against mixing with the subsequently deposited organic semiconductor layer. Density functional theory calculations show that the robustness arises from a strong interaction of carboxylate groups with the Ag surface, and thus, the BTB in the first layer is energetically favored. Synchrotron radiation photoelectron spectroscopy shows that this layer displays considerable electrical dipoles that can be utilized for work function engineering and electronic alignment of molecular frontier orbitals with respect to the substrate Fermi level. Our work thus provides a widely applicable molecular interlayer and general insights necessary for engineering of charge injection layers for efficient organic electronics.

Nationwide observational study of paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) in the Czech Republic.

The worldwide outbreak of the novel 2019 coronavirus disease (COVID-19) has led to recognition of a new immunopathological condition: paediatric inflammatory multisystem syndrome (PIMS-TS). The Czech Republic (CZ) suffered from one of the highest incidences of individuals who tested positive during pandemic waves. The aim of this study was to analyse epidemiological, clinical, and laboratory characteristics of all cases of paediatric inflammatory multisystem syndrome (PIMS-TS) in the Czech Republic (CZ) and their predictors of severe course. We performed a retrospective-prospective nationwide observational study based on patients hospitalised with PIMS-TS in CZ between 1 November 2020 and 31 May 2021. The anonymised data of patients were abstracted from medical record review. Using the inclusion criteria according to World Health Organization definition, 207 patients with PIMS-TS were enrolled in this study. The incidence of PIMS-TS out of all SARS-CoV-2-positive children was 0.9:1,000. The estimated delay between the occurrence of PIMS-TS and the COVID-19 pandemic wave was 3 weeks. The significant initial predictors of myocardial dysfunction included mainly cardiovascular signs (hypotension, oedema, oliguria/anuria, and prolonged capillary refill). During follow-up, most patients (98.8%) had normal cardiac function, with no residual findings. No fatal cases were reported.Conclusions: A 3-week interval in combination with incidence of COVID-19 could help increase pre-test probability of PIMS-TS during pandemic waves in the suspected cases. Although the parameters of the models do not allow one to completely divide patients into high and low risk groups, knowing the most important predictors surely could help clinical management.

Karyotyping of Lymphocytes and Epithelial Cells of Distinct Embryonic Origin Does Not Help to Predict the Turner Syndrome Features.

BACKGROUND: In Turner syndrome (TS), fluorescent in situ hybridization (FISH) karyotyping offers an alternative to classical karyotyping. OBJECTIVE: We tested the added value of FISH karyotyping from lymphocytes (mesodermal origin), buccal cells (ectodermal origin), and a rear-tongue smear (endodermal origin) to determine the 45,X cell line fraction and its impact on patient phenotype. DESIGN AND PATIENTS: Classical karyotyping and three FISH assays were done in 153 girls and women previously diagnosed with TS in four university hospitals. The 45,X cell line fraction was determined for each method and correlated with the major phenotypic signs. RESULTS: Classical karyotyping identified 45,X/46,XX mosaicism in 77/153 subjects (50%), 45,X monosomy in 52/153 (34%), and other karyotypes in 24/153 (16%). FISH from lymphocytes verified 45,X in 47/52 original cases, whereas 4/52 had 45,X/46,XX and 1/52 45,X/47,XYY mosaicism. The 45,X cell line fraction was higher in FISH from lymphocytes compared to classical karyotyping (median 86.4% vs. 70.0%; p < 0.001), while there was no difference for FISH from buccal or rear-tongue smear cells. The mean 45,X cell line fraction was more abundant in patients with several of the characteristic phenotypic signs compared to patients without them (p < 0.01), but the predictive power was insufficient. CONCLUSION: FISH analysis confirmed the findings of classical karyotyping; only a few 45,X monosomy cases were reclassified as mosaics. The 45,X cell line fraction did not show clinically meaningful prediction of the phenotype. FISH analysis of buccal or rear-tongue epithelial cells may be a non-inferior, less invasive alternative to classical karyotyping.

Haplotype analysis of the X chromosome in patients with Turner syndrome in order to verify the possible effect of imprinting on selected symptoms.

AIMS: Turner syndrome is the only chromosome monosomy that is postnatally compatible with life. The reported incidence of TS is 1 in 2500 liveborn girls. The phenotype of these girls is highly variable, with cardiac abnormalities being life-threatening defects. The aim of the study was to reveal the possible influence of the parental origin of the X chromosome in these patients on a selected phenotype that is associated with Turner syndrome. Selected symptoms and parameters were: a bicuspid aortic valve, aortic coarctation, lymphoedema, pterygium colli, coeliac disease, thyroiditis, otitis media, diabetes mellitus 2, renal abnormalities, spontaneous puberty, and IVF. METHODS: The X chromosome haplotype was determined for a group of 45,X patients verified by native FISH. A molecular diagnostic method based on the detection of different lengths of X chromosome-linked STR markers using the Argus X-12 QS kit was used to determine the X haplotype. RESULTS: Our results, analysed by Fisher's exact (factorial) test, suggest independence between the maternal/paternal origin of the inherited X chromosome and the presence of the anomalies that were studied (P=1 to P=0.34). CONCLUSION: In the group of 45,X patients, who were precisely selected by means of the native FISH method, no correlation was demonstrated with the parental origin of the X chromosome and the observed symptom.

Effect of handling on ATP utilization of cerebral Na,K-ATPase in rats with trimethyltin-induced neurodegeneration.

Previously it was shown that for reduction of anxiety and stress of experimental animals, preventive handling seems to be one of the most effective methods. The present study was oriented on Na,K-ATPase, a key enzyme for maintaining proper concentrations of intracellular sodium and potassium ions. Malfunction of this enzyme has an essential role in the development of neurodegenerative diseases. It is known that this enzyme requires approximately 50% of the energy available to the brain. Therefore in the present study utilization of the energy source ATP by Na,K-ATPase in the frontal cerebral cortex, using the method of enzyme kinetics was investigated. As a model of neurodegeneration treatment with trimethyltin (TMT) was applied. Daily handling (10 min/day) of healthy rats and rats suffering neurodegeneration induced by administration of TMT in a dose of (7.5 mg/kg), at postnatal days 60-102 altered the expression of catalytic subunits of Na,K-ATPase as well as kinetic properties of this enzyme in the frontal cerebral cortex of adult male Wistar rats. In addition to the previously published beneficial effect on spatial memory, daily treatment of rats was accompanied by improved maintenance of sodium homeostasis in the frontal cortex. The key system responsible for this process, Na,K-ATPase, was able to utilize better the energy substrate ATP. In rats, manipulation of TMT-induced neurodegeneration promoted the expression of the α2 isoform of the enzyme, which is typical for glial cells. In healthy rats, manipulation was followed by increased expression of the α3 subunit, which is typical of neurons.

Pigmentary retinopathy can indicate the presence of pathogenic LAMP2 variants even in somatic mosaic carriers with no additional signs of Danon disease.

PURPOSE: Danon disease (DD) is a rare X-linked disorder caused by pathogenic variants in LAMP2. DD primarily manifests as a severe cardiomyopathy. An early diagnosis is crucial for patient survival. The aim of the study was to determine the usefulness of ocular examination for identification of DD. METHODS: Detailed ocular examination in 10 patients with DD (3 males, 7 females) and a 45-year-old asymptomatic female somatic mosaic carrier of a LAMP2 disease-causing variant. RESULTS: All patients with manifest cardiomyopathy had pigmentary retinopathy with altered autofluorescence and diffuse visual field loss. Best corrected visual acuity (BCVA) was decreased (<0.63) in 8 (40%) out of 20 eyes. The severity of retinal pathology increased with age, resulting in marked cone-rod involvement overtime. Spectral-domain optical coherence tomography in younger patients revealed focal loss of photoreceptors, disruption and deposition at the retinal pigment epithelium/Bruch's membrane layer (corresponding to areas of marked increased autofluorescence), and hyperreflective foci in the outer nuclear layer. Cystoid macular oedema was seen in one eye. In the asymptomatic female with somatic mosaicism, the BCVA was 1.0 bilaterally. An abnormal autofluorescence pattern in the left eye was present; while full-field electroretinography was normal. CONCLUSIONS: Detailed ocular examination may represent a sensitive and quick screening tool for the identification of carriers of LAMP2 pathogenic variants, even in somatic mosaicism. Hence, further investigation should be undertaken in all patients with pigmentary retinal dystrophy as it may be a sign of a life-threatening disease.

Cardiac profile of the Czech population of Duchenne muscular dystrophy patients: a cardiovascular magnetic resonance study with T1 mapping.

BACKGROUND: The progressive cardiomyopathy that develops in boys with Duchenne and Becker muscular dystrophy (DMD/BMD) is presumed to be a secondary consequence of the fibrosis within the myocardium. There are only limited data on using parametric imaging in these patients. The purpose of this study was to assess native T1 and extracellular volume (ECV) values in DMD patients. METHODS: The Czech population of males with DMD/BMD was screened. All eligible patients fulfilling the inclusion criteria were included. Forty nine males underwent cardiac magnetic resonance (MR) examination including T1 native and post-contrast mapping measurements. One DMD patient and all BMD patients were excluded from statistical analysis. Three groups were compared - Group D1 - DMD patients without late gadolinium enhancement (LGE) (n = 23), Group D2 - DMD patients with LGE (n = 20), and Group C - gender matched controls (n = 13). RESULTS: Compared to controls, both DMD groups had prolonged T1 native relaxation time. These results are concordant in all 6 segments as well as in global values (1041 ± 31 ms and 1043 ± 37 ms vs. 983 ± 15 ms, both p < 0.05). Group D2 had significantly increased global ECV (0.28 ± 0.044 vs. 0.243 ± 0.013, p < 0.05) and segmental ECV in inferolateral and anterolateral segments in comparison with controls. The results were also significant after adjustment for subjects' age. CONCLUSION: DMD males had increased native T1 relaxation time independent of the presence or absence of myocardial fibrosis. Cardiac MR may provide clinically useful information even without contrast media administration.

Ambipolar remote graphene doping by low-energy electron beam irradiation.

We employ low-energy electron beam irradiation to induce both n- and p-doping in a graphene layer. Depending on the applied gate voltage during the irradiation, either n- or p-doping can be achieved, and by setting an appropriate irradiation protocol, any desired doping levels can be achieved.

LAMP2 exon-copy number variations in Danon disease heterozygote female probands: Infrequent or underdetected?

Danon disease (DD) is an X-linked disorder caused by mutations in the lysosomal-associated membrane protein 2 (LAMP2) gene (Xq24). DD is characterized by cognitive deficit, myopathy, and cardiomyopathy in male patients. The phenotype is variable and mitigated in females. The timely identification of de-novo LAMP2 mutated family members, many of whom are heterozygous females, remains critical for their treatment and family counseling. DD laboratory testing builds on minimally invasive quantification of the LAMP2 protein in white blood cells and characterization of the specific mutation. This integrative approach is particularly helpful when assessing suspect female heterozygotes. LAMP2 exon-copy number variations (eCNVs) were so far reported only in X-hemizygous male DD probands. In heterozygous female DD probands, the wild-type allele may hamper the identification of an eCNV even if it results in the complete abolition of LAMP2 transcription and/or translation. To document the likely underappreciated rate of occurrence and point out numerous potential pitfalls of detection of the LAMP2 eCNVs, we present the first two DD heterozygote female probands who harbor novel multi-exon LAMP2 deletions. Critical for counseling and recurrence prediction, we also highlight the need to search for somatic-germinal mosaicism in DD families.

Beneficial effect of 6 weeks lasting handling of adult rats on spatial memory in experimental model of neurodegeneration.

Handling is a form of experience which can result in physiological changes depending on the period of postnatal age when performed. There is a lot of evidence about the positive effect of neonatal handling, but a lack dealing with handling of adult rats. Behavioral changes and memory deficits are present in dementia-like disorders. In the present work, we tested whether 6 weeks lasting handling of young adult rats could revert memory impairment induced by trimethyltin (TMT) (7.5 mg/kg, intraperitoneally). Testing rats in Morris water maze revealed significant effect of TMT as well significant effect of handling. We observed improvement of spatial memory also between healthy, non-degenerated rats as well as degenerated rats, represented by shorter latency onto the platform. In our paper, we report beneficial effect of handling on spatial memory that is in compliance with published works about beneficial effect of cognitive therapy and training in patients with early stage of Alzheimer΄s disease and dementia.

Increased prevalence of bicuspid aortic valve in Turner syndrome links with karyotype: the crucial importance of detailed cardiovascular screening.

BACKGROUND: Bicuspid aortic valve (BAV) represents one of the strongest risk factors for aortic dissection in Turner syndrome (TS). An exact relation between the occurrence of BAV and a particular karyotype has not been established yet. The aim of this study was to determine the association between karyotype and prevalence of BAV. METHODS: Sixty-seven TS patients aged between 6.6 and 32.5 years underwent cardiac magnetic resonance imaging (MRI) study. They were divided into four cytogenetic subgroups-45,X karyotype (n=27); 45,X/46,XX mosaicism (n=17); structural abnormalities of the X chromosome (n=10); and 45,X/structural abnormality of the X chromosome mosaicism (n=13). Prevalence of BAV and odds ratio (OR) compared with the general population in the whole study group, and statistical comparison of prevalences of BAV among the individual subgroups were determined. RESULTS: Prevalence of BAV in the whole study group was established as 28.4% [OR 208.3 (95% CI - 103.8-418.0); p-value<0.0001]. Individuals with 45,X karyotype had the highest prevalence of BAV - 40.7%, p-value<0.0001. Presence of any 45,X cell line in karyotype significantly predisposed to BAV (p-value=0.05). CONCLUSIONS: The 45,X karyotype is associated with the highest prevalence of BAV. Also, the presence of the 45,X cell line in any mosaic karyotype increases the probability of BAV.

Progressive increase of lysosomal enzyme activities in hippocampus associated with reduction of population spike in a rat model of neurodegeneration.

OBJECTIVES: Extensive effort has been made to identify early markers of neurodegeneration as late stages have no chance of treatment. Recently, many experimental models have been used to study hallmarks of neuronal injury. One of them is the model of trimethyltin (TMT)-induced damage associated with cognitive decline, thus called a model of Alzheimer-like disease. OBJECTIVE AND METHODS: Our aim was to study neuronal transmission in hippocampal slices of male Wistar rats affected with a single dose of TMT (7.5 mg/kg, i.p.) during the first three weeks of its action. The monitored time periods after TMT administration were days 1-3; 8-10 and 15-17. At the same time periods, right hippocampi were collected for determination of changes in specific activities of two lysosomal enzymes. Electrophysiological measurements were based on stimulation of Schäffer collaterals and registration of evoked responses in the stratum pyramidale and the stratum radiatum at the CA3-CA1 synapse. Specific activities of N-acetyl-ß-D-glucosaminidase (NAGA) and cathepsin D (Cat D) were determined spectrophotometrically. RESULTS: During three weeks after i.p. TMT administration to rats, we found a time-dependent reduction of postsynaptic neuronal firing, expressed by diminished population spike (PoS) amplitude recorded in the stratum pyramidale accompanied with marked increase in specific activity of NAGA to respective 111%, 163% and 252% in the 1st, 2nd and 3rd week compared to unaffected rats. In the stratum radiatum, reduction of the slope of excitatory postsynaptic potential was not time-dependent but almost constantly reduced from the 1st to 3rd week after TMT administration (55-60%) compared to control rats. Specific activity of lysosomal enzyme Cat D was significantly increased in the 3rd week after TMT administration. CONCLUSION: This work demonstrates a time-dependent reduction of somatic response in the hippocampus of TMT affected rats during the first three weeks. This reduction of neuronal firing was later accompanied with increase of specific activity of NAGA and Cat D, supporting evidence that lysosomal dysfunction may be one of the primary contributors to TMT-induced neurodegeneration.

In Vitro Metabolomic Approach to Hippocampal Neurodegeneration Induced by Trimethyltin.

Search for indicators of neurodegenerative disorders is a hot topic where much research remains to be done. Our aim was to determine proton nuclear magnetic resonance ((1)H-NMR) spectra of brain metabolites in the trimethyltin (TMT) model of neurodegeneration. Male Wistar rats were subjected to TMT or saline and were sacrificed on day 3 or 24 after administration. (1)H-NMR spectrum was measured on the 600 MHz Varian VNMRS spectrometer in nano-probe in the volume of 40 µl of hippocampal extracts. TMT administration resulted in reduction of the hippocampal weight on day 24. Of the sixteen identified metabolite spectra, decreased aspartate and increased glutamine contents were observed in the initial asymptomatic stage of neurodegeneration on day 3 in hippocampal extracts of TMT exposed rats compared to sham animals. Increased myo-inositol content was observed on day 24. The presented data provide further knowledge about this experimental model and putative indicators of neuronal damage.

Pyridoindole antioxidant-induced preservation of rat hippocampal pyramidal cell number linked with reduction of oxidative stress yet without influence on cognitive deterioration in Alzheimer-like neurodegeneration.

BACKGROUND: The idea of antioxidant therapy attenuating Alzheimer disease (AD) neuropathology starts to be attractive. Animal models are often used in these studies. An AD-like model of trimethyltin (TMT)-induced neurodegeneration, targeting the hippocampus, involves neuronal cell death and cognitive impairment. OBJECTIVES: Effect of the pyridoindole SMe1EC2 (3×50 mg/kg) and vitamin C (3×50mg/kg) was analyzed in the model of TMT-induced (8 mg/kg) neurodegeneration. METHODS: The study was focused on the effect of the antioxidants tested on learning performance in the Morris water maze (MWM) on days 21-25 after TMT administration, on biochemical variables - malondyaldehyde (MDA) and lysosomal enzyme NAGA in brain cortex and blood serum, and on pyramidal cell number in the CA1 area of the hippocampus on day 31 after TMT administration in adult male Wistar rats (n=32). RESULTS: Critical deterioration of learning performance was observed due to the TMT administration in the MWM. Further, apparent reduction of pyramidal cell number to 21% in the CA1 area of the hippocampus, increased MDA and NAGA activity in serum and increased NAGA activity in the cortex were determined contrary to controls. In serum, an increase of MDA level was prevented by both antioxidants tested without any effect on NAGA activity. SMe1EC2 apparently preserved pyramidal cell viability in the CA1 area. Both substances tested failed to ameliorate the detrimental effect of TMT on spatial memory. CONCLUSION: The biochemical and morphometrical findings suggest that reduction of oxidative stress may play a role in AD-like neurodegeneration. Different doses and timing of SMe1EC2 administration might bring improvement in next learning performance.

Effect of antioxidants on functional recovery after in vitro-induced ischemia and long-term potentiation recorded in the pyramidal layer of the CA1 area of rat hippocampus.

Ischemic stroke is one of the leading causes of cognitive impairment. Antioxidants may be beneficial in brain diseases in which oxidative stress can be assumed. The effect of two antioxidants, stobadine and its new derivative coded SMe1EC2, was studied on post-ischemic functional recovery in the hippocampus of young and 18-month-old rats. The synaptic transmission was apparently absent after 6-min hypoxia/hypoglycemia in both age groups. Re-oxygenation resulted in negligible functional recovery in untreated slices, yet the presence of pyridoindoles tested elicited improved recovery upon re-oxygenation. SMe1EC2 was found more effective in post-ischemic functional recovery and was further tested in the hippocampus of 15-month-old rats in long-term potentiation (LTP) experiments, a synaptic model of learning and memory mechanisms. In slices of aged rats, 3.5-min hypoxia/hypoglycemia resulted in depression of the LTP induction phase (immediately after high frequency stimulation) and this was prevented in the presence of SMe1EC2 (3 µmol/l). Upon "normoxia", marked amelioration of LTP was recorded in the presence of the antioxidant in about 1.5 order lower concentration. These results suggest a possible application of the pyridoindole in the management of brain ischemia and cognitive impairment.

Discordant expression of a new WT1 gene mutation in a family with monozygotic twins presenting with congenital nephrotic syndrome.

Congenital nephrotic syndrome (CNS) is a heterogeneous group of diseases with different causes and prognoses. Two thirds of cases of NS in the first year of life are caused by mutations in four genes (NPHS1, NPHS2, WT1, and LAMB2). The mutation of WT1 gene can lead to Denys-Drash syndrome (DDS). We report on female monozygotic twins with CNS presenting at 7 and 8 weeks of age with anuric renal failure. Both twins were treated by peritoneal dialysis. Renal biopsy proved diffuse mesangial sclerosis. Genetic analysis detected a new heterozygote WT1 mutation R434P in both twins. One child developed a unilateral nephroblastoma. Both twins died because of complications of CNS (sepsis and extensive thrombosis of central venous system/sepsis and sudden heart failure) at ages 23 weeks/13.5 months, respectively. DNA analysis showed the same WT1 mutation in the father, who showed at his age of 41 years no clinical consequences of this mutation and no signs of DDS. In conclusion, we report the third family with monozygotic twins with DDS due to WT1 mutation. The DDS has very rapidly led to end-stage renal failure and death in both twins which is in striking contrast to the manifestation in their father.

Early and late stage of neurodegeneration induced by trimethyltin in hippocampus and cortex of male Wistar rats.

BACKGROUND: Trimethyltin (TMT), a potent neurotoxicant, elicits neuronal death in the limbic system and causes damage particularly in the hippocampus. Current interest relates to the opportunity to use TMT as an experimental model of neurodegeneration in the study of Alzheimer-like diseases. OBJECTIVE: In light of recently found species-specific and strain-specific differences in TMT intoxication, the aim of this study was to characterise the model of TMT-induced neurodegeneration in the brain of Wistar rats during early (days 1-3) and late (days 22-24) stage of neuronal damage. RESULTS: Reduced neurotransmission at the CA3-CA1 synapse and reduced number of cells accompanied with reduced width of CA1 pyramidal cell layer were observed at the late stage of TMT intoxication (7 mg/kg, i.p.). Long-term potentiation of excitatory postsynaptic potential, elicited by train stimulation (100 Hz, 1s), was not impaired by the dose of TMT tested. Activation of pro-apoptotic caspase-3 suggests involvement of apoptosis in neuronal cell death in the hippocampus at the late stage of TMT intoxication. Increased protein carbonyl formation was proved in the cortex at the early stage of TMT intoxication compared both to controls in the early and late stage and to the late stage of TMT action. CONCLUSIONS: TMT-induced neurodegeneration was proved in the brain of Wistar rats. Changes found in the parameters examined may be reliable indicators of neurodegeneration. The increased level of carbonyls in the cortex at the early stage indicates that particularly at the onset of progressive neurodegeneration compounds with antioxidative properties may be effective in slowing down brain injury.