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1.
Opt Express ; 31(18): 28946-28953, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710703

RESUMO

We demonstrate transitional dimensionality of discrete diffraction in radial-elliptical photonic lattices. Varying the order, characteristic structure size, and ellipticity of the Mathieu beams used for the photonic lattices generation, we control the shape of discrete diffraction distribution over the combination of the radial direction with the circular, elliptic, or hyperbolic. We also investigate the transition from one-dimensional to two-dimensional discrete diffraction by varying the input probe beam position. The most pronounced discrete diffraction is observed along the crystal anisotropy direction.

2.
Eur Radiol ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37991508

RESUMO

OBJECTIVES: To investigate if the effect of cardiac computed tomography (CT) vs. invasive coronary angiography (ICA) on cardiovascular events differs based on smoking status. MATERIALS AND METHODS: This pre-specified subgroup analysis of the pragmatic, prospective, multicentre, randomised DISCHARGE trial (NCT02400229) involved 3561 patients with suspected coronary artery disease (CAD). The primary endpoint was major adverse cardiovascular events (MACE: cardiovascular death, non-fatal myocardial infarction, or stroke). Secondary endpoints included an expanded MACE composite (MACE, transient ischaemic attack, or major procedure-related complications). RESULTS: Of 3445 randomised patients with smoking data (mean age 59.1 years + / - 9.7, 1151 men), at 3.5-year follow-up, the effect of CT vs. ICA on MACE was consistent across smoking groups (p for interaction = 0.98). The percutaneous coronary intervention rate was significantly lower with a CT-first strategy in smokers and former smokers (p = 0.01 for both). A CT-first strategy reduced the hazard of major procedure-related complications (HR: 0.21, 95% CI: 0.03, 0.81; p = 0.045) across smoking groups. In current smokers, the expanded MACE composite was lower in the CT- compared to the ICA-first strategy (2.3% (8) vs 6.0% (18), HR: 0.38; 95% CI: 0.17, 0.88). The rate of non-obstructive CAD was significantly higher in all three smoking groups in the CT-first strategy. CONCLUSION: For patients with stable chest pain referred for ICA, the clinical outcomes of CT were consistent across smoking status. The CT-first approach led to a higher detection rate of non-obstructive CAD and fewer major procedure-related complications in smokers. CLINICAL RELEVANCE STATEMENT: This pre-specified sub-analysis of the DISCHARGE trial confirms that a CT-first strategy in patients with stable chest pain referred for invasive coronary angiography with an intermediate pre-test probability of coronary artery disease is as effective as and safer than invasive coronary angiography, irrespective of smoking status. TRIAL REGISTRATION: ClinicalTrials.gov NCT02400229. KEY POINTS: • No randomised studies have assessed smoking status on CT effectiveness in symptomatic patients referred for invasive coronary angiography. • A CT-first strategy results in comparable adverse events, fewer complications, and increased coronary artery disease detection, irrespective of smoking status. • A CT-first strategy is safe and effective for stable chest pain patients with intermediate pre-test probability for CAD, including never smokers.

3.
Phys Chem Chem Phys ; 25(39): 26648-26658, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37772423

RESUMO

Triacetone triperoxide (TATP) is a highly potent homemade explosive commonly used in terrorist attacks. Its detection poses a significant challenge due to its volatility, and the lack of portability of current sensing techniques. To address this issue, we propose a novel approach based on single-molecule TATP detection in the air using a device where tunneling current in N-terminated carbon-nanotubes nanogaps is measured. By employing the density functional theory combined with the non-equilibrium Green's function method, we show that current of tens of nanoamperes passes through TATP trapped in the nanogap, with a discrimination ratio of several orders of magnitude even against prevalent indoor volatile organic compounds (VOCs). This high tunneling current through TATP's highest occupied molecular orbital (HOMO) is facilitated by the strong electric field generated by N-C polar bonds at the electrode ends and by the hybridization between TATP and the electrodes, driven by oxygen atoms within the probed molecule. The application of the same principle is discussed for graphene nanogaps and break-junctions.

4.
J Neurosci Res ; 99(1): 407-418, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32729199

RESUMO

Lithium is widely used to treat bipolar disorder. However, the efficacy and vulnerability as to its side effects are known to differ. Although the specific biochemical mechanism of action is still elusive, lithium may influence mitochondrial function, and consequently, metabolism. Lithium exposure in this study was conducted on a unique set of mito-nuclear introgression lines of Drosophila subobscura to disentangle the independent effects of mitochondrial DNA (mtDNA) against a common nuclear DNA background. The study addressed three issues: (a) whether lithium has a dose-dependent effect on whole-organism metabolic rate, (b) whether mtDNA haplotypes show divergent metabolic efficiency measured by metabolic rate to lithium exposure and (c) whether lithium influences the whole-organism metabolic rate across sexes. The results confirm that lithium influenced the whole-organism metabolic rate, showing a subtle balance between efficacy and adverse effects within a narrow dose range. In addition, lithium exposure was found to influence metabolism differently based on mtDNA haplotypes and sex. This preliminary research may have a range of biological implications for the role of mitochondrial variability in psychiatric disease and treatment by contributing to the understanding and predicting of the lithium treatment response and risk for toxic side effects.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Compostos de Lítio/toxicidade , Mitocôndrias/efeitos dos fármacos , Sulfatos/toxicidade , Animais , Drosophila , Feminino , Masculino
5.
Stem Cells ; 38(3): 369-381, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31778245

RESUMO

Thyroid hormones are regarded as the major controllers of metabolic rate and oxygen consumption in mammals. Although it has been demonstrated that thyroid hormone supplementation improves bovine embryo development in vitro, the cellular mechanisms underlying these effects are so far unknown. In this study, we investigated the role of thyroid hormone in development of human preimplantation embryos. Embryos were cultured in the presence or absence of 10-7 M triiodothyronine (T3) till blastocyst stage. Inner cell mass (ICM) and trophectoderm (TE) were separated mechanically and subjected to RNAseq or quantification of mitochondrial DNA copy number. Analyses were performed using DESeq (v1.16.0 on R v3.1.3), MeV4.9 and MitoMiner 4.0v2018 JUN platforms. We found that the exposure of human preimplantation embryos to T3 had a profound impact on nuclear gene transcription only in the cells of ICM (1178 regulated genes-10.5% of 11 196 expressed genes) and almost no effect on cells of TE (38 regulated genes-0.3% of expressed genes). The analyses suggest that T3 induces in ICM a shift in ribosome and oxidative phosphorylation activity, as the upregulated genes are contributing to the composition and organization of the respiratory chain and associated cofactors involved in mitoribosome assembly and stability. Furthermore, a number of genes affecting the citric acid cycle energy production have reduced expression. Our findings might explain why thyroid disorders in women have been associated with reduced fertility and adverse pregnancy outcome. Our data also raise a possibility that supplementation of culture media with T3 may improve outcomes for women undergoing in vitro fertilization.


Assuntos
Blastocisto/metabolismo , Mitocôndrias/metabolismo , Hormônios Tireóideos/metabolismo , Feminino , Humanos , Fosforilação Oxidativa , Gravidez
6.
Chemphyschem ; 22(3): 336-341, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33245835

RESUMO

Functionalization of electrodes is a wide-used strategy in various applications ranging from single-molecule sensing and protein sequencing, to ion trapping, to desalination. We demonstrate, employing non-equilibrium Green's function formalism combined with density functional theory, that single-species (N, H, S, Cl, F) termination of graphene nanogap electrodes results in a strong in-gap electrostatic field, induced by species-dependent dipoles formed at the electrode ends. Consequently, the field increases or decreases electronic transport through a molecule (benzene) placed in the nanogap by shifting molecular levels by almost 2 eV in respect to the electrode Fermi level via a field effect akin to the one used for field-effect transistors. We also observed the local gating in graphene nanopores terminated with different single-species atoms. Nitrogen-terminated nanogaps (NtNGs) and nanopores (NtNPs) show the strongest effect. The in-gap potential can be transformed from a plateau-like to a saddle-like shape by tailoring NtNG and NtNP size and termination type. In particular, the saddle-like potential is applicable in single-ion trapping and desalination devices.

7.
Front Zool ; 18(1): 55, 2021 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-34689812

RESUMO

BACKGROUND: Mammalian mandible and cranium are well-established model systems for studying canalization and developmental stability (DS) as two elements of developmental homeostasis. Nematode infections are usually acquired in early life and increase in intensity with age, while canalization and DS of rodent skulls could vary through late postnatal ontogeny. We aimed to estimate magnitudes and describe patterns of mandibular and cranial canalization and DS related to age and parasite intensity (diversity) in adult yellow-necked mice (Apodemus flavicollis). RESULTS: We found the absence of age-related changes in the levels of canalization for mandibular and cranial size and DS for mandibular size. However, individual measures of mandibular and cranial shape variance increased, while individual measures of mandibular shape fluctuating asymmetry (FA) decreased with age. We detected mandibular and cranial shape changes during postnatal ontogeny, but revealed no age-related dynamics of their covariance structure among and within individuals. Categories regarding parasitism differed in the level of canalization for cranial size and the level of DS for cranial shape. We observed differences in age-related dynamics of the level of canalization between non-parasitized and parasitized animals, as well as between yellow-necked mice parasitized by different number of nematode species. Likewise, individual measures of mandibular and cranial shape FA decreased with age for the mandible in the less parasitized category and increased for the cranium in the most parasitized category. CONCLUSIONS: Our age-related results partly agree with previous findings. However, no rodent study so far has explored age-related changes in the magnitude of FA for mandibular size or mandibular and cranial FA covariance structure. This is the first study dealing with the nematode parasitism-related canalization and DS in rodents. We showed that nematode parasitism does not affect mandibular and cranial shape variation and covariance structure among and within individuals. However, parasite intensity (diversity) is related to ontogenetic dynamics of the levels of canalization and DS. Overall, additional studies on animals from natural populations are required before drawing some general conclusions.

8.
Acta Clin Croat ; 59(1): 183-187, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32724292

RESUMO

Giant cavernomas (GC) are rare lesions, with less than 50 cases reported so far. Clinical presentation usually involves epileptic seizures and less typically focal neurological deficit, due to repeated hemorrhages and GC mass effect and consequentially increased intracranial pressure. Although individual cases have been reported, due to the rarity and variable imaging appearance, GCs are usually not considered in the differential diagnosis of large hemorrhagic lesions, especially when significant mass effect is present. A 17-year-old boy presented due to severe headache, right-sided weakness, and slurred speech. Symptoms started three days before with occasional headaches, which intensified gradually. Emergency computed tomography revealed a left frontal massive heterogeneous lesion. Soon after, right-sided hemiparesis and speech impairment progressed, and the patient became drowsy with the slightly dilated left pupil. Emergency surgery was performed, and the lobed grayish lesion was entirely removed. Based on the macroscopic appearance, the surgeon assumed it was a metastasis of melanoma. Histopathologic analysis result was cavernoma. GC should be considered as an option in hemorrhagic lesions, especially in the young age population. Emergency surgery for mass lesions is not uncommon in neurosurgery; however, bleeding cavernomas are usually planned for elective surgery due to the specific approach and complications.


Assuntos
Hemangioma Cavernoso do Sistema Nervoso Central , Adolescente , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico por imagem , Hemangioma Cavernoso do Sistema Nervoso Central/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Procedimentos Neurocirúrgicos , Tomografia Computadorizada por Raios X
9.
Croat Med J ; 60(2): 78-86, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31044579

RESUMO

AIM: To characterize stem cells originating from different dental tissues (apical papilla [SCAP], dental follicle [DFSC], and pulp [DPSC]) and test the capacity of Raman microspectroscopy to distinguish between the three dental stem cell types. METHODS: SCAP, DFSC, and DPSC cultures were generated from three immature wisdom teeth originating from three patients. Cell stemness was confirmed by inducing neuro-, osteo-, chondro-, and adipo-differentiaton and by mesenchymal marker expression analysis by flow-cytometry and real-time polymerase chain reaction. Cellular components were then evaluated by Raman microspectroscopy. RESULTS: We found differences between SCAP, DFSC, and DPSC Raman spectra. The ratio between proteins and nucleic acids (748/770), a parameter for discriminating more differentiated from less differentiated cells, showed significant differences between the three cell types. All cells also displayed a fingerprint region in the 600-700 cm-1 range, and characteristic lipid peaks at positions 1440 cm-1 and 1650 cm-1. CONCLUSION: Although different dental stem cells exhibited similar Raman spectra, the method enabled us to make subtle distinction between them.


Assuntos
Polpa Dentária/citologia , Saco Dentário/citologia , Células-Tronco Mesenquimais/química , Dente Serotino/citologia , Análise Espectral Raman , Adolescente , Diferenciação Celular , Citometria de Fluxo , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Células-Tronco , Dente
10.
Acta Vet Hung ; 67(3): 338-346, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31549550

RESUMO

The greatest epidemiological significance of leptospirosis in Europe comes from the fact that it is the most widespread zoonosis in the world. However, epizootiological data, especially information on maintenance hosts such as small wild mammals, are largely missing. To fill this gap in data in Serbia, we used RT-PCR for the detection of pathogenic Leptospira species and analysed 107 animals belonging to six species of small wild mammals (Apodemus agrarius, Apodemus flavicollis, Microtus arvalis, Myodes glareolus, Microtus subterraneus and Sorex araneus) collected from two localities. The animals from the first locality that was situated in a tourist area, were collected for four consecutive years (2014-2017). We found persistent incidence of infection from year to year ranging from 6.67% to 78.57%. The average frequency of infected animals was 33.3% with the highest frequency in 2014, the year characterised by a very high number of flooding days. All animals proved to be infected with pathogenic Leptospira species that were collected from the second locality situated in an agricultural area in a single year, 2014. The findings show a variable but constant presence of pathogenic Leptospira species in populations of small wild mammals in the studied areas, which indicates the need for constant monitoring.


Assuntos
Arvicolinae , Leptospira/isolamento & purificação , Leptospirose/veterinária , Murinae , Doenças dos Roedores/epidemiologia , Musaranhos , Animais , Incidência , Leptospirose/epidemiologia , Leptospirose/microbiologia , Prevalência , Doenças dos Roedores/microbiologia , Sérvia/epidemiologia
11.
J Neurosci ; 37(29): 7036-7047, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28630255

RESUMO

Communication is an inherently interactive process that weaves together the fabric of both human and nonhuman primate societies. To investigate the properties of the primate brain during active social signaling, we recorded the responses of frontal cortex neurons as freely moving marmosets engaged in conversational exchanges with a visually occluded virtual marmoset. We found that small changes in firing rate (∼1 Hz) occurred across a broadly distributed population of frontal cortex neurons when marmosets heard a conspecific vocalization, and that these changes corresponded to subjects' likelihood of producing or withholding a vocal reply. Although the contributions of individual neurons were relatively small, large populations of neurons were able to clearly distinguish between these social contexts. Most significantly, this social context-dependent change in firing rate was evident even before subjects heard the vocalization, indicating that the probability of a conversational exchange was determined by the state of the frontal cortex at the time a vocalization was heard, and not by a decision driven by acoustic characteristics of the vocalization. We found that changes in neural activity scaled with the length of the conversation, with greater changes in firing rate evident for longer conversations. These data reveal specific and important facets of this neural activity that constrain its possible roles in active social signaling, and we hypothesize that the close coupling between frontal cortex activity and this natural, active primate social-signaling behavior facilitates social-monitoring mechanisms critical to conversational exchanges.SIGNIFICANCE STATEMENT We provide evidence for a novel pattern of neural activity in the frontal cortex of freely moving, naturally behaving, marmoset monkeys that may facilitate natural primate conversations. We discovered small (∼1 Hz), but reliable, changes in neural activity that occurred before marmosets even heard a conspecific vocalization that, as a population, almost perfectly predicted whether subjects would produce a vocalization in response. The change in the state of the frontal cortex persisted throughout the conversation and its magnitude scaled linearly with the length of the interaction. We hypothesize that this social context-dependent change in frontal cortex activity is supported by several mechanisms, such as social arousal and attention, and facilitates social monitoring critical for vocal coordination characteristic of human and nonhuman primate conversations.


Assuntos
Comportamento Animal/fisiologia , Callithrix/fisiologia , Lobo Frontal/fisiologia , Comportamento Social , Vocalização Animal/fisiologia , Comunicação Animal , Animais , Feminino , Masculino
12.
J Neural Transm (Vienna) ; 124(5): 621-629, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28084537

RESUMO

Suicidal behavior has been associated with a deficient serotonin neurotransmission which is likely a consequence of individual genetic architecture, exposure to environmental factors and interactions of those factors. We examined whether the interaction of child abuse, TPH2 (tryptophan hydroxylase 2) variant rs4290270, affecting alternative splicing and editing of TPH2 pre-mRNAs, and ADARB1 (adenosine deaminase acting on RNA B1) variants rs4819035 and rs9983925 may influence the risk for suicide attempt in psychiatric patients. TPH2 rs4290270 was genotyped in 165 suicide attempters and 188 suicide non-attempters diagnosed with major depressive disorder, bipolar disorder and schizophrenia. Genotyping data for ADARB1 variants were taken over from our previous study. Child abuse before the age of 18 years was assessed using the Early Trauma Inventory-Self Report. Generalized linear models and backward selection were applied to identify the main and interacting effects of environmental and genetic factors, including psychiatric diagnoses, patients' gender and age as covariates. Childhood general traumas were independently associated with suicide attempt. Two-way interaction between TPH2 rs4290270 and general traumas revealed that TT homozygotes with a history of general traumas had an increased risk for suicide attempt. Three-way interaction of general traumas, TPH2 rs4290270 and ADARB1 rs4819035 indicated that the highest predisposition to suicide attempt was observed in individuals who experienced general traumas and were TT homozygote for rs4290270 and TT homozygote for rs4819035. Our findings suggest that the risk for suicide attempt in psychiatric patients exposed to an adverse childhood environment may depend on TPH2 and ADARB1 variants.


Assuntos
Adenosina Desaminase/genética , Sobreviventes Adultos de Maus-Tratos Infantis , Transtornos Mentais/genética , Transtornos Mentais/psicologia , Proteínas de Ligação a RNA/genética , Tentativa de Suicídio , Triptofano Hidroxilase/genética , Adenosina Desaminase/metabolismo , Adulto , Feminino , Interação Gene-Ambiente , Variação Genética , Técnicas de Genotipagem , Humanos , Modelos Lineares , Masculino , Isoformas de Proteínas , Proteínas de Ligação a RNA/metabolismo , Fatores de Risco , Psicologia do Esquizofrênico , Triptofano Hidroxilase/metabolismo
13.
J Hum Genet ; 60(11): 723-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26311540

RESUMO

Spinal muscular atrophy (SMA) is caused by functional loss of the survival of motor neuron 1 (SMN1) gene. Despite genetic homogeneity, phenotypic variability indicates the involvement of disease modifiers. SMN1 is located in 5q13.2 segmental duplication, enriched in genes and prone to unequal rearrangements, which results in copy number polymorphism (CNP). We examined the influence of CNP of 5q13.2 genes and their joint effect on childhood-onset SMA phenotype. Multiplex ligation-dependent probe amplification (MLPA) was used to construct 5q13.2 alleles and assess copy number of the SMN2, small EDRK-rich factor 1A (SERF1A) and NLR family apoptosis inhibitory protein (NAIP) genes in 99 Serbian patients with SMN1 homozygous absence (23-type I, 37-type II and 39-mild type III) and 122 patients' parents. Spearman rank test was performed to test correlation of individual genes and SMA type. Generalized linear models and backward selection were performed to obtain a model explaining phenotypic variation with the smallest set of variables. 5q13.2 alleles most commonly associated with type I harbored large-scale deletions, while those detected in types II and III originated from conversion of SMN1 to SMN2. Inverse correlation was observed between SMN2, SERF1A and NAIP CNP and SMA type (P=2.2e-16, P=4.264e-10, P=2.722e-8, respectively). The best minimal model describing phenotypic variability included SMN2 (P<2e-16), SERF1A (P<2e-16) and their interaction (P=0.02628). SMN2 and SERF1A have a joint modifying effect on childhood-onset SMA phenotype.


Assuntos
Proteínas do Tecido Nervoso/genética , Atrofias Musculares Espinais da Infância/genética , Idade de Início , Criança , Cromossomos Humanos Par 5/genética , Variações do Número de Cópias de DNA , Feminino , Rearranjo Gênico , Humanos , Masculino , Modelos Genéticos , Proteína Inibidora de Apoptose Neuronal/genética , Fenótipo , Sérvia , Proteína 2 de Sobrevivência do Neurônio Motor/genética
14.
Phys Chem Chem Phys ; 16(24): 12393-406, 2014 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-24827580

RESUMO

In this work, we present a complete mechanistic picture of the non-radiative decay of the mono-substituted aromatic compound nitrobenzene from the bright singlet state to the electronic ground state. This mechanism involves internal conversion (IC) and inter-system crossing (ISC) along three dominating internal coordinates of the nitro group and consistently explains the experimental findings. Relaxation from the lowest triplet state via ISC occurs along the out-of-plane bending coordinate of the nitro group, while initial IC as well as ultrafast ISC into the triplet manifold take place along symmetric NO stretching and ONO bending modes that have not been considered yet. The proposed mechanism is based on high-level single- and multi-reference electronic structure calculations employing ADC3, MOM-CCSD(T), EOM-CCSD, DFT/MRCI and CAS-SCF/NEVPT2 levels of theory, which is, as we will demonstrate, absolutely necessary to assure a reliable and sufficiently accurate theoretical description of nitrobenzene. The need for third-order methods will be traced back to the large double-excitation character of about 50% of the second excited singlet state of nitrobenzene. As a result, second-order methods like approximate coupled-cluster of second order (CC2) and partially even (EOM-)CCSD yield a qualitatively wrong picture of the excited states. Surprisingly, already the description of the ground state geometries is problematic at the CC2 and partially also CCSD level of theory.

15.
bioRxiv ; 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38260273

RESUMO

Biological relatedness is a key consideration in studies of behavior, population structure, and trait evolution. Except for parent-offspring dyads, pedigrees capture relatedness imperfectly. The number and length of DNA segments that are identical-by-descent (IBD) yield the most precise estimates of relatedness. Here, we leverage novel methods for estimating locus-specific IBD from low coverage whole genome resequencing data to demonstrate the feasibility and value of resolving fine-scaled gradients of relatedness in free-living animals. Using primarily 4-6× coverage data from a rhesus macaque (Macaca mulatta) population with available long-term pedigree data, we show that we can call the number and length of IBD segments across the genome with high accuracy even at 0.5× coverage. The resulting estimates demonstrate substantial variation in genetic relatedness within kin classes, leading to overlapping distributions between kin classes. They identify cryptic genetic relatives that are not represented in the pedigree and reveal elevated recombination rates in females relative to males, which allows us to discriminate maternal and paternal kin using genotype data alone. Our findings represent a breakthrough in the ability to understand the predictors and consequences of genetic relatedness in natural populations, contributing to our understanding of a fundamental component of population structure in the wild.

16.
J Phys Chem A ; 117(30): 6474-82, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23819719

RESUMO

Because of the presence of polar groups in picolinamide, its aqueous solvation is characterized by formation of multiple hydrogen bonds, which are responsible for differences in vibrational spectra of picolinamide in the gas phase and its aqueous solution. In this contribution, we try to identify dominant interactions between the solute and the solvent molecules that are the origin of the observed spectral changes. For this purpose, we analyzed the vibrational properties of picolinamide (a single molecule and also embedded in the environment described with an implicit solvent model) and picolinamide-water dimers: by comparing their vibrational frequencies with experimentally observed values of picolinamides' aqueous solution and by analyzing the computed anharmonic force constants, it is possible to recognize whether and in which way the solvent causes changes in the vibrational properties of the title compound. Calculations performed on the picolinamide three-hydrate confirm conclusions obtained by analyzing monohydrates.


Assuntos
Modelos Químicos , Ácidos Picolínicos/química , Água/química , Amidas/química , Dicroísmo Circular , Simulação por Computador , Dimerização , Gases , Ligação de Hidrogênio , Soluções , Espectrofotometria Infravermelho , Termodinâmica
17.
J Cancer Res Clin Oncol ; 149(3): 1049-1061, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35246724

RESUMO

OBJECTIVES: Perioperative chemo-(radio-) therapy is the accepted standard in European patients with locally advanced adenocarcinoma of the esophagogastric junction or stomach (AEG/AS). However, 30-85% of patients do not respond to this treatment. The aim of our study was the identification of predictive biomarkers in pre-therapeutic endoscopic tumor biopsies from patients with histopathologic response (Becker-1) versus non-response (Becker-2/3) to preoperative chemotherapy. METHODS: Formalin-fixed paraffin-embedded biopsies from 36 Caucasian patients (Becker-1 n = 11, Becker-2 n = 7, Becker-3 n = 18) with AEG/AS, taken prior to neoadjuvant chemotherapy were selected. For RNA expression analysis, we employed the NanoString nCounter System. To identify genomic alterations like single nucleotide variants (SNV), copy number variation (CNV) and fusion events, we used Illumina TST170 gene panel. For HER2 and FGFR2 protein expression, immunostaining was performed. Furthermore, we analyzed the microsatellite instability (MSI) and Epstein-Barr virus (EBV) infection status by EBER in situ hybridization. RESULTS: Heat map and principal component analyses showed no clustering by means of gene expression according to regression grade. Concerning two recently proposed predictive markers, our data showed equal distribution for MSI (Becker-1: 2; Becker-2: 1; Becker-3: 3; out of 29 tested) and EBV infection was rare (1/32). We could not reveal discriminating target genes concerning SNV, but found a higher mutational burden in non-responders versus responders and fusion (in 6/14) and CNV events (in 5/14) exclusively in Becker-3. CONCLUSIONS: Although we could not identify discriminating target genes, our data suggest that molecular alterations are in general more prevalent in patients with AEG/AS belonging to the non-responding Becker group 3.


Assuntos
Adenocarcinoma , Infecções por Vírus Epstein-Barr , Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Terapia Neoadjuvante , Neoplasias Gástricas/patologia , Infecções por Vírus Epstein-Barr/patologia , Variações do Número de Cópias de DNA , Herpesvirus Humano 4/genética , Junção Esofagogástrica/patologia , Instabilidade de Microssatélites , Perfilação da Expressão Gênica , Adenocarcinoma/patologia , Biópsia , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias Esofágicas/patologia
19.
Nano Lett ; 11(7): 2875-80, 2011 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-21627099

RESUMO

For advanced electronic, optoelectronic, or mechanical nanoscale devices a detailed understanding of their structural properties and in particular the strain state within their active region is of utmost importance. We demonstrate that X-ray nanodiffraction represents an excellent tool to investigate the internal structure of such devices in a nondestructive way by using a focused synchotron X-ray beam with a diameter of 400 nm. We show results on the strain fields in and around a single SiGe island, which serves as stressor for the Si-channel in a fully functioning Si-metal-oxide semiconductor field-effect transistor.


Assuntos
Germânio/química , Nanotecnologia , Pontos Quânticos , Silício/química , Transistores Eletrônicos , Tamanho da Partícula , Semicondutores , Propriedades de Superfície , Raios X
20.
Neuron ; 110(8): 1318-1326.e4, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35108498

RESUMO

We tested whether social signal processing in more traditional, head-restrained contexts is representative of the putative natural analog-social communication-by comparing responses to vocalizations within individual neurons in marmoset prefrontal cortex (PFC) across a series of behavioral contexts ranging from traditional to naturalistic. Although vocalization-responsive neurons were evident in all contexts, cross-context consistency was notably limited. A response to these social signals when subjects were head-restrained was not predictive of a comparable neural response to the identical vocalizations during natural communication. This pattern was evident both within individual neurons and at a population level, as PFC activity could be reliably decoded for the behavioral context in which vocalizations were heard. These results suggest that neural representations of social signals in primate PFC are not static but highly flexible and likely reflect how nuances of the dynamic behavioral contexts affect the perception of these signals and what they communicate.


Assuntos
Córtex Pré-Frontal , Vocalização Animal , Animais , Callithrix , Humanos , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Vocalização Animal/fisiologia
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