Exposure to chronic hypoxia results in pulmonary hypertension characterized by increased vascular resistance and pulmonary vascular remodeling, changes in functional parameters of the pulmonary ...vasculature, and right ventricular hypertrophy, which can eventually lead to right heart failure. The underlying mechanisms of hypoxia-induced pulmonary hypertension have still not been fully elucidated while no curative treatment is currently available. Commonly employed pre-clinical analytic methods are largely limited to invasive studies interfering with cardiac tissue or otherwise ex vivo functional studies and histopathology. In this work, we suggest volumetric optoacoustic tomography (VOT) for non-invasive assessment of heart function in response to chronic hypoxia. Mice exposed for 3 consecutive weeks to normoxia or chronic hypoxia were imaged in vivo with heart perfusion tracked by VOT using indocyanide green contrast agent at high temporal (100 Hz) and spatial (200 µm) resolutions in 3D. Unequivocal difference in the pulmonary transit time was revealed between the hypoxic and normoxic conditions concomitant with the presence of pulmonary vascular remodeling within hypoxic models. Furthermore, a beat-to-beat analysis of the volumetric image data enabled identifying and characterizing arrhythmic events in mice exposed to chronic hypoxia. The newly introduced non-invasive methodology for analysis of impaired pulmonary vasculature and heart function under chronic hypoxic exposure provides important inputs into development of early diagnosis and treatment strategies in pulmonary hypertension.
Purpose
Myocardial healing following myocardial infarction (MI) is a complex process that is yet to be fully understood. Clinical attempts in regeneration of the injured myocardium using cardiac stem ...cells faced major challenges, calling for a better understanding of the processes involved at a more basic level in order to foster translation.
Procedures
We examined the feasibility of volumetric optoacoustic tomography (VOT) in studying healing of the myocardium in different models of MI, including permanent occlusion (PO) of the left coronary artery, temporary occlusion (ischemia-reperfusion—I/R) and infarcted c-kit mutants, a genetic mouse model with impaired cardiac healing. Murine hearts were imaged at 100 Hz frame rate using 800 nm excitation wavelength, corresponding to the peak absorption of indocyanine green (ICG) in plasma and the isosbestic point of haemoglobin.
Results
The non-invasive real-time volumetric imaging capabilities of VOT have allowed the detection of significant variations in the pulmonary transit time (PTT), a parameter affected by MI, across different murine models. Upon intravenous injection of ICG, we were able to track alterations in cardiac perfusion in I/R models, which were absent in wild-type (
wt
) PO or
kit
W
/kit
W-v
PO mice. The
wt-
PO and I/R models further exhibited irregularities in their cardiac cycles.
Conclusions
Clear differences in the PTT, ICG perfusion and cardiac cycle patterns were identified between the different models and days post MI. Overall, the results highlight the unique capacity of VOT for multi-parametric characterization of morphological and functional changes in murine models of MI.
Although relatively rare, major trauma to the tracheal region of the airways poses a significant clinical challenge with few effective treatments. Bioengineering and regenerative medicine strategies ...have the potential to create biocompatible, implantable biomaterial scaffolds, with the capacity to restore lost tissue with functional neo-trachea. The main goal of this study was to develop a nanofibrous polycaprolactone-chitosan (PCL-Chitosan) scaffold loaded with a signaling molecule, all-
retinoic acid (atRA), as a novel biomaterial approach for tracheal tissue engineering. Using the Spraybase® electrospinning platform, polymer concentration, solvent selection, and instrument parameters were optimized to yield a co-polymer with nanofibers of 181-197 nm in diameter that mimicked tracheobronchial tissue architecture. Thereafter, scaffolds were assessed for their biocompatibility and capacity to induce mucociliary functionalization using the Calu-3 cell line. PCL-Chitosan scaffolds were found to be biocompatible in nature and support Calu-3 cell viability over a 14 day time period. Additionally, the inclusion of atRA did not compromise Calu-3 cell viability, while still achieving an efficient encapsulation of the signaling molecule over a range of atRA concentrations. atRA release from scaffolds led to an increase in mucociliary gene expression at high scaffold loading doses, with augmented MUC5AC and FOXJ1 detected by RT-PCR. Overall, this scaffold integrates a synthetic polymer that has been used in human tracheal stents, a natural polymer generally regarded as safe (GRAS), and a drug with decades of use in patients. Coupled with the scalable nature of electrospinning as a fabrication method, all of these characteristics make the biomaterial outlined in this study amenable as an implantable device for an unmet clinical need in tracheal replacement.
Tendon injuries resulting from accidents and aging are increasing globally. However, key tendon functional parameters such as microvascularity and oxygen perfusion remain inaccessible via the ...currently available clinical diagnostic tools, resulting in disagreements on optimal treatment options. Here, a new noninvasive method for anatomical and functional characterization of human tendons based on multispectral optoacoustic tomography (MSOT) is reported. Healthy subjects are investigated using a hand‐held scanner delivering real‐time volumetric images. Tendons in the wrist, ankle, and lower leg are imaged in the near‐infrared optical spectrum to utilize endogenous contrast from Type I collagen. Morphology of the flexor carpi ulnaris, carpi radialis, palmaris longus, and Achilles tendons are reconstructed in full. The functional roles of the flexor digitorium longus, hallicus longus, and the tibialis posterior tendons have been visualized by dynamic tracking during toe extension‐flexion motion. Furthermore, major vessels and microvasculature near the Achilles tendon are localized, and the global increase in oxygen saturation in response to targeted exercise is confirmed by perfusion studies. MSOT is shown to be a versatile tool capable of anatomical and functional tendon assessments. Future studies including abnormal subjects can validate the method as a viable noninvasive clinical tool for tendinopathy management and healing monitoring.
Hand‐held multispectral optoacoustic tomography imaging of healthy tendons in human subjects demonstrates the potential for noninvasive, label‐free anatomical visualization and functional motion tracking. Furthermore, various vasculature groups in and around the Achilles tendon can be localized. Blood perfusion studies reveal a diversity of oxygenation dynamics in response to targeted exercise, providing insights into the contentious topic of tendon healing.
Volumetric optoacoustic tomography has been shown to provide unprecedented capabilities for ultrafast imaging of cardiovascular dynamics in mice. Three-dimensional imaging rates in the order of 100 ...Hz have been achieved, which enabled the visualization of transient cardiac events such as arrhythmias or contrast agent perfusion without the need for retrospective gating. The fast murine heart rates (400–600 beats per minute) yet impose limitations when it comes to compounding of multiple frames or accurate registration of multi-spectral data. Herein, we investigate on the capabilities of Fourier analysis of four-dimensional data for coregistration of independent volumetric optoacoustic image sequences of the heart. The fundamental frequencies and higher harmonics of respiratory and cardiac cycles could clearly be distinguished, which facilitated efficient retrospective gating without additional readings. The performance of the suggested methodology was successfully demonstrated by compounding cardiac images acquired by raster-scanning of a spherical transducer array as well as by unmixing of oxygenated and deoxygenated hemoglobin from multi-spectral optoacoustic data.
Brojevi su raznolika vrsta riječi, mogu biti jednočlani i višečlani, neki su sklonjivi, neki su nesklonjivi, u brojeve se ubrajaju i brojevne imenice i brojevni pridjevi, pa se i tipovi sklonidbe ...razlikuju. unatoč tome, opisu njihove tvorbe posvećeno je malo prostora. Babić u
Tvorbi riječi u hrvatskome književnome jeziku
to tumači ovako: „Koliko među zamjenicama, brojevima, prijedlozima i veznicima i ima tvorbenih riječi, to ih je samo nekoliko i tipovi više nisu plodni. To su većinom za tvorbu riječi zatvoreni sustavi, jer nema novih osnova, često s malim brojem jedinica...ˮ (Babić 2002: 15). u
Hrvatskome mrežnom rječniku – Mrežniku
predviđeno je da se obradi i tvorba riječi, no pri obradi brojeva i riječi motiviranih brojevima pokazalo se da dosadašnji opisi tvorbe koji se nalaze u gramatikama ne nude sva rješenja, što ih čini manjkavima. u radu će se analizirati tvorba brojeva i riječi tvorenih od brojeva koje su obrađene u
Mrežniku
.
Numbers are usually defined as words that describe how many units there are of what the word denotes, or how many units should be counted to come to some object. They are a heterogeneous group; they can be simple or complex, some are declinable while some are indeclinable. As a word group, numbers include nouns and adjectives, so the types of declination are different. Despite this diversity, the description of their word formation is not as detailed. In
Tvorba riječi u hrvatskome književnome jeziku
, Babić explains: “Among the pronouns, numbers, prepositions, and conjunctions, there are words formed from others, but these are just a few, and the types of formation are no longer productive. From the aspect of word formation, these are mostly closed systems, because there are no new root words, and there is a small number of units...” (Babić 2002: 15). Word-formation data will be provided in the
Croatian Web Dictionary – Mrežnik
, but when describing numbers and words motivated by numbers, it has been shown that current descriptions in grammars are not sufficient. In this paper, the wordformatting models of numbers and words formed from numbers included in
Mrežnik
are analyzed and roots and suffixes are determined.
Proverbs as concise textual structures are primarily defined as oral (folk) literary forms in which universal thoughts are expressed on the basis of individual experiences understandable to speakers ...of the language, i.e., of the social community in which they originated. In relation to, for example, idioms, the use of proverbs in today’s public discourse is much rarer, and proverbs in Croatian are most often recorded in printed form, while online edited lexicographic sources of proverbs are rare. Folk customs, human character and physical features, social and religious values, the relation of human and nature are the most common motives in proverbs. Male-female relationships are also the subject of numerous proverbs. Given the past times when they were created, they can be considered the source of a stereotypical image of the status of women and men in society that exists in human consciousness. Based on proverbs with the component woman, grandmother, mother, daughter, sister, girlfriend, widow, father, son, husband…, this paper will analyze proverbs with the topic of male-female relations, e.g. Ljubav daj ženi, ali tajnu odaj samo majci i sestri. (Give your love to your wife, but reveal the secret only to your mother and sister.), or proverbs referring to an individual feature attributed to a man or a woman, e.g., Kakvo drvo, takav klin, kakav otac takav sin. (Like tree, like wedge; like father, like son.)., Ženi sina kad hoćeš, a kćer kad možeš. (Marry a son when you want and a daughter when you can.). The analysis includes the following: 1. representation of proverbs in other lexicographic (printed and online sources), 2. representation of such proverbs in contemporary public discourse, 3. structural and semantic features of proverbs motivated by male-female relationships. In conclusion, the role of proverbs on the topic of male and female in the contemporary context is discussed – what is their perspective and whether the corpus has replaced traditional recorders and word of mouth today.
Poslovice kao sažete tekstne strukture primarno se određuju kao usmeni (narodni) književni oblici u kojima se iznose univerzalne misli utemeljene na pojedinačnim iskustvima prepoznatljivim i razumljivim govornicima jezične, tj. društvene zajednice u kojoj su nastale. Danas, u odnosu, primjerice, na frazeme, primjena poslovica u javnome diskursu znatno je rjeđa, a poslovice se u hrvatskom jeziku bilježe najčešće u tiskanoj formi, dok su uređeni mrežni izvori u kojima se donosi popis poslovica rijetki. Običaji, ljudske karakterne i tjelesne osobine, društvene i vjerske vrijednosti, čovjek i priroda najčešći su motivi o kojima poslovice progovaraju. Među njima, muško-ženski odnosi također su tema brojnih poslovica koje se, s obzirom na prošla vremena kad su nastale, mogu smatrati izvorom stereotipne i predrasudne slike o statusu žene i muškarca u društvu koja postoji u čovjekovoj svijesti. Na temelju poslovica sa sastavnicom žena, baba, majka, kći, sestra, cura, udovica, otac, sin, muž, sluga…) u radu se analiziraju poslovice u kojima se obrađuju muško-ženski odnosi (npr. Ljubav daj ženi, ali tajnu odaj samo majci i sestri.), odnosno koje upućuju na neku pojedinačnu osobinu koja se pripisuje muškarcu ili ženi (npr. Kakvo drvo, takav klin, kakav otac takav sin.). Analiza uključuje sljedeće: 1. izrazna (strukturna) i značenjska obilježja poslovica motiviranih muško-ženskim odnosima, 2. zastupljenost takvih poslovica u drugim leksikografskim mrežnim izvorima, 3. zastupljenost takvih poslovica u suvremenome javnom diskursu. U zaključku se raspravlja o ulozi poslovica na temu muško i žensko u suvremenom kontekstu – kakva im je perspektiva i je li korpus danas zamijenio tradicionalne zapisivače i usmenu predaju.
Složeni prijedložni spojevi Ivankovic, Ivana Matas
Rasprave Instituta za hrvatski jezik i jezikoslovlje,
12/2016, Letnik:
42, Številka:
2
Journal Article
Recenzirano
Prepositions are relational words; they connect head and dependent word. Most of syntagmatic expressions with prepositions come as free combinations, but some of them are multiword expressions that ...cannot be decomposed semantically and syntactically. This paper deals with multiword expressions with prepositions, that cannot be decomposed into component parts because this would lead to a grammatically unacceptable expressions (dodir između materije i duha ‘contact between matter and spirit’ cannot be dodir između materije ‘contact between matter’), or their meaning would change (zaštita od požara ‘fire protection’ is different from zaštita ‘protection’). The paper also addresses prepositions combined with semantically important, but structurally optional words such as modifiers (daleko iza sebe ‘far behind himself’). Depending on their relations, multiword expressions with prepositions are divided into 8 groups.
Noninvasive Imaging
The article number 2308336 by Daniel Razansky and co‐workers reports a new non‐invasive approach for anatomical and functional characterization of human tendons based on ...multispectral optoacoustic tomography (MSOT). The method offers real‐time, volumetric, label‐free imaging with functional and molecular contrast, making it well‐suited for evaluating the dynamic morphology and perfusion of tendons in response to controlled motion and exercise.
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