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1.
Int J Mol Sci ; 24(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37298356

RESUMO

The infamous "master manipulators"-intracellular bacteria of the genus Wolbachia-infect a broad range of phylogenetically diverse invertebrate hosts in terrestrial ecosystems. Wolbachia has an important impact on the ecology and evolution of their host with documented effects including induced parthenogenesis, male killing, feminization, and cytoplasmic incompatibility. Nonetheless, data on Wolbachia infections in non-terrestrial invertebrates are scarce. Sampling bias and methodological limitations are some of the reasons limiting the detection of these bacteria in aquatic organisms. In this study, we present a new metagenetic method for detecting the co-occurrence of different Wolbachia strains in freshwater invertebrates host species, i.e., freshwater Arthropoda (Crustacea), Mollusca (Bivalvia), and water bears (Tardigrada) by applying NGS primers designed by us and a Python script that allows the identification of Wolbachia target sequences from the microbiome communities. We also compare the results obtained using the commonly applied NGS primers and the Sanger sequencing approach. Finally, we describe three supergroups of Wolbachia: (i) a new supergroup V identified in Crustacea and Bivalvia hosts; (ii) supergroup A identified in Crustacea, Bivalvia, and Eutardigrada hosts, and (iii) supergroup E infection in the Crustacea host microbiome community.


Assuntos
Artrópodes , Wolbachia , Animais , Masculino , Wolbachia/genética , Filogenia , Ecossistema , Bactérias , Crustáceos , Simbiose
2.
J Happiness Stud ; 23(8): 3889-3908, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213306

RESUMO

Individuals increase well-being by acting on their values rather than merely endorsing them. We developed a novel intervention ("Acting on Values," AoV), motivating individuals to initiate values-related behavior over four weeks. Building upon the theory of Basic Human Values, we expected that intervention recipients would increase their hedonic and eudaimonic well-being relative to a control group. We also expected the AoV interventions to cause similar effects as a mindfulness group. 783 volunteers (N = 268 completers) were assigned into three groups: AoV intervention, mindfulness, and a waiting list. Individuals who completed the AoV intervention achieved higher satisfaction with life, positive affect, and eudaimonic well-being, and lower negative affect than the control group. The well-being effects of the AoV intervention did not differ significantly from the mindfulness intervention effects. Our findings suggest that the AoV intervention is an efficacious method of increasing hedonic and eudaimonic well-being. It contributes to the diversity of well-being facilitation methods. Supplementary Information: The online version contains supplementary material available at 10.1007/s10902-022-00585-4.

3.
Prog Mol Subcell Biol ; 59: 305-327, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34050872

RESUMO

Tardigrada (also known as "water bears") are hydrophilous microinvertebrates with a bilaterally symmetrical body and four pairs of legs usually terminating with claws. Water bears are quite complex animals and range from 50 to 1200 µm in length. Their body is divided into a head segment and four trunk segments, each bearing a pair of legs. They inhabit almost all terrestrial and aquatic environments, from the ocean depths to highest mountains ranges. However, one of their best known and unusual features is their capability for cryptobiosis. In this state tardigrades are able to survive extremely low and high temperatures and atmospheric pressures, complete lack of water, high doses of radiation, high concentrations of toxins and even a cosmic vacuum. The cellular mechanisms enabling cryptobiosis are poorly understood, although it appears the synthesis of certain types of molecules (sugars and proteins) enable the prevention of cellular damage at different levels. The endoplasmic reticulum (ER) is a morphologically and functionally diverse organelle able to integrate multiple extracellular and internal signals and generate adaptive cellular responses. However, the ER morphology and activity in the case of tardigrades has been studied rarely and in the context of oogenesis, functioning of the digestive system, and in the role and function of storage cells. Thus, there are no direct studies on the contribution of the ER in the ability of this organism to cope with environmental stress during cryptobiosis. Nevertheless, it is highly probable that the ER has a crucial role in this uncommon process. Since water bears are easy to handle laboratory animals, they may represent an ideal model organism to uncover the important role of the ER in the cell response to extreme environmental stress conditions.


Assuntos
Retículo Endoplasmático , Tardígrados , Animais , Retículo Endoplasmático/genética , Estresse do Retículo Endoplasmático/genética , Modelos Animais , Estresse Fisiológico , Tardígrados/genética
4.
Front Zool ; 18(1): 15, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33794934

RESUMO

Anhydrobiosis can be described as an adaptation to lack of water that enables some organisms, including tardigrades, to survive extreme conditions, even some that do not exist on Earth. The cellular mechanisms underlying anhydrobiosis are still not completely explained including the putative contribution of mitochondrial proteins. Since mitochondrial alternative oxidase (AOX), described as a drought response element in plants, was recently proposed for various invertebrates including tardigrades, we investigated whether AOX is involved in successful anhydrobiosis of tardigrades. Milnesium inceptum was used as a model for the study. We confirmed functionality of M. inceptum AOX and estimated its contribution to the tardigrade revival after anhydrobiosis of different durations. We observed that AOX activity was particularly important for M. inceptum revival after the long-term tun stage but did not affect the rehydration stage specifically. The results may contribute to our understanding and then application of anhydrobiosis underlying mechanisms.

5.
Genome ; 64(10): 951-958, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34015229

RESUMO

We used high-throughput sequencing of 16S rRNA to test whether tardigrade species are infected with Wolbachia parasites. We applied SILVA and Greengenes databases that allowed taxonomic classification of bacterial sequences to OTUs. The results obtained from both databases differed considerably in the number of OTUs, and only the Greengenes database allowed identification of Wolbachia (infection was also supported by comparison of sequences to NCBI database). The putative bacterial endosymbiont Wolbachia was discovered only in adult eutardigrades, while bacteria identified down to the order Rickettsiales were detected in both eutardigrade eggs and adult specimens. Nevertheless, the frequency of Wolbachia in the bacterial communities of the studied eutardigrades was low. Similarly, in our positive control, i.e., a fairy shrimp Streptocephalus cafer, which was found to be infected with Wolbachia in our previous study using Sanger sequencing, only the Rickettsiales were detected. We also carried out phylogenetic reconstruction using Wolbachia sequences from the SILVA and Greengenes databases, Alphaproteobacteria putative endosymbionts and Rickettsiales OTUs obtained in previous studies on the microbial community of tardigrades, and Rickettsiales and Wolbachia OTUs obtained in the current study. Our discovery of Wolbachia in tardigrades can fuel new research to uncover the specifics of this interaction.


Assuntos
Filogenia , Tardígrados/microbiologia , Wolbachia , Animais , Sequenciamento de Nucleotídeos em Larga Escala , RNA Ribossômico 16S/genética , Simbiose , Wolbachia/classificação
6.
Orig Life Evol Biosph ; 51(3): 231-257, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34363564

RESUMO

Earth is one of the inner planets of the Solar System, but - unlike the others - it has an oxidising atmosphere, relatively stable temperature, and a constant geomagnetic field (GMF). The GMF does not only protect life on Earth against the solar wind and cosmic rays, but it also shields the atmosphere itself, thus creating relatively stable environmental conditions. What is more, the GMF could have influenced the origins of life: organisms from archaea to plants and animals may have been using the GMF as a source of spatial information since the very beginning. Although the GMF is constant, it does undergo various changes, some of which, e.g. a reversal of the poles, weaken the field significantly or even lead to its short-term disappearance. This may result in considerable climatic changes and an increased frequency of mutations caused by the solar wind and cosmic radiation. This review analyses data on the influence of the GMF on different aspects of life and it also presents current knowledge in the area. In conclusion, the GMF has a positive impact on living organisms, whereas a diminishing or disappearing GMF negatively affects living organisms. The influence of the GMF may also be an important factor determining both survival of terrestrial organisms outside Earth and the emergence of life on other planets.


Assuntos
Radiação Cósmica , Planeta Terra , Animais , Atmosfera , Planetas
7.
Mol Phylogenet Evol ; 145: 106730, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31904510

RESUMO

In a moss samples collected on Madagascar two populations of Paramacrobiotus experimentalis sp. nov. were found. Paramacrobiotus experimentalis sp. nov. with the presence of a microplacoid and areolatus type of eggs is similar to Pam. danielae, Pam. garynahi, Pam. hapukuensis, Pam. peteri, Pam. rioplatensis and Pam. savai, but it differs from them by some morphological and morphometric characters of the eggs. The p-distance between two COI haplotypes of Pam. experimentalis sp. nov. was 0.17%. In turn, the ranges of uncorrected genetic p-distances of all Paramacrobiotus species available in GenBank was from 18.27% (for Pam. lachowskae) to 25.26% (for Pam. arduus) with an average distance of 20.67%. We also found that Pam. experimentalis sp. nov. is bisexual. This observation was congruent on three levels: (i) morphological - specimen size dimorphism; (ii) structural (primary sexual characteristics) - females have an unpaired ovary while males have an unpaired testis and (iii) molecular - heterozygous and homozygous strains of the ITS-2 marker. Although symbiotic associations of hosts with bacteria (including endosymbiotic bacteria) are common in nature and these interactions exert various effects on the evolution, biology and reproductive ecology of hosts, there is still very little information on the bacterial community associated with tardigrades. To fill this gap and characterise the bacterial community of Pam. experimentalis sp. nov. populations and microbiome of its microhabitat, high throughput sequencing of the V3-V4 hypervariable regions in the bacterial 16S rRNA gene fragment was performed. The obtained 16S rRNA gene sequences ranged from 92,665 to 131,163. In total, 135 operational taxonomic units (OTUs) were identified across the rarefied dataset. Overall, both Pam. experimentalis sp. nov. populations were dominated by OTUs ascribed to the phylum Proteobacteria (89-92%) and Firmicutes (6-7%). In the case of samples from tardigrades' laboratory habitat, the most abundant bacterial phylum was Proteobacteria (51-90%) and Bacteroides (9-48%). In all compared microbiome profiles, only 16 of 137 OTUs were shared. We found also significant differences in beta diversity between the partly species-specific microbiome of Pam. experimentalis sp. nov. and its culturing environment. Two OTUs belonging to a putative bacterial endosymbiont were identified - Rickettsiales and Polynucleobacter. We also demonstrated that each bacterial community was rich in genes involved in membrane transport, amino acid metabolism, and carbohydrate metabolism.


Assuntos
Microbiota , Tardígrados/classificação , Animais , Bacteroides/genética , Bacteroides/isolamento & purificação , DNA Bacteriano/química , DNA Bacteriano/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Madagáscar , Masculino , Mitocôndrias/genética , Filogenia , Proteobactérias/genética , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/classificação , RNA Ribossômico 18S/genética , Simbiose , Tardígrados/genética , Tardígrados/microbiologia
8.
Med Chem Res ; 26(12): 3354-3366, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29170613

RESUMO

An optimization of the guanidylation process by verifying the efficacy of common guanylation reagents in order to obtain the guanidine derivatives of indolo[2,3-b]quinoline has been performed. As a result, a high-yield procedure using N,N'-di-Boc-N''-triflylguanidine was applied to synthesize the guanidine derivative of indolo[2,3-b]quinoline 1 in a gram scale for specific in vitro and in vivo biological research. Extensive studies on the antiproliferative activity against eight human tumor cell lines were completed. Compound 1 revealed the highest activity against A549 lung adenocarcinoma and MCF7 breast cancer cell lines. Thus, 1 was evaluated for the in vivo anticancer activity against 4T1 mammary gland carcinoma and KLN205 murine lung carcinoma in mouse models. The anticancer effect was observed in the KLN205 model with a 37% tumor growth inhibition at the 20 mg/kg dose. This anticancer activity of 1 was comparable to that of cyclophosphamide which inhibited murine lung tumor growth in the range of 27-43% at the dose of 100 mg/kg. The biochemistry research after 1 admission, including measurements of blood parameters like alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and urea and creatinine, were also performed.

9.
Acta Pol Pharm ; 73(3): 683-92, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27476287

RESUMO

Novel 5H-indolo[2,3-b]quinoline O-aminoglycosides were synthesized in order to check the hypothesis that the construction of hybrids composed of the active 5H-indolo[2,3-b]quinoline chromophore and daunosaminyl or acosaminyl moiety may result in the cytotoxic activity of the obtained derivatives that is much higher than the one of the parent DIMIQ (5,11-dimethyl-5H-indolo[2,3-b]quinoline) and 6H-indoloquinoline analogs. Actually, 5H-indolo[2,3-b]indoloquinoline O-aminoglycosides showed the anti-proliferative activity in vitro against human lung adenocarcinoma A549, breast cancer MCF-7, melanoma Hs294T, promyelocytic leukemia HL-60, uterine sarcoma MES-SA and colon cancer LoVo cell lines, which was 10 times higher than that of the 6H-analogs and comparable to the one of the referential DIMIQ. Unexpectedly, it appeared that except for HL-60/MX2 (P-gp-independent and topoisomerase II-dependent resistance), other MDR tumor cell lines (LoVo/DX. P-gp-dependent, MRP-, LRP-dependent multidrug resistance) and MES-SA/DX5 (P-gp-dependent resistance to doxorubicin) are also resistant to the 5H-indolo[2,3-b]indoloquinoline O-aminoglycosides tested. This is surprising because 6H-analogs, in general, 10 times less active against non-MDR tumor cell lines, as well as the DIMIQ itself, are able to overcome drug resistance in all MDR cell lines examined. The cytotoxicity of the tested compounds against tumor cell lines and against normal cells (mice fibroblasts BALB/3T3) was comparable.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Glicosídeos/síntese química , Glicosídeos/farmacologia , Quinolinas/síntese química , Quinolinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Relação Estrutura-Atividade
10.
Psychiatr Pol ; 49(1): 135-44, 2015.
Artigo em Polonês | MEDLINE | ID: mdl-25844416

RESUMO

AIM: Depressive disorders, which remain one of the most common and recurrent mood disorders worldwide, presently affect up to 15% of the population under age 25. Adolescent depression is related to a number of adverse phenomena such as scholastic/academic failure, juvenile delinquency, illicit substance abuse or suicide. Studies show that students are at a high risk of developing this disorder but depression in this population is often misdiagnosed and undertreated. Consequently, it is important to develop reliable diagnostic tools to evaluate symptoms of depression in students. Kutcher Adolescent Depression Scale (brief version) is a commonly used screening test used to identify young people at risk for depression, which consists of six items related to its main symptoms. The aim of the study was to adapt and test reliability and content validity of the Polish version of six - item Kutcher's KADS based on analysis of students using confirmatory factor analysis. MATERIAL AND METHODS: A total of 1,589 student aged 18-24 anonymously answered a questionnaire on the risk of depression (KADS) and a demographics survey. RESULTS: Confirmatory factor analysis showed the good fit of model to empirical data: SB χ² (15) = 968.688, p < .001, RMSEA = .053, CFI = .958, SRMR = .029. Factor loading ranged from .40 to .80. CONCLUSIONS: Validation of Polish version of KADS in a group of students aged 18-24 years has shown its high reliability and content validity. Further studies should be focused on the assessment of the questionnaire criterion validity.


Assuntos
Depressão/diagnóstico , Transtorno Depressivo/diagnóstico , Autoavaliação Diagnóstica , Estudantes/psicologia , Inquéritos e Questionários/normas , Adolescente , Feminino , Humanos , Masculino , Polônia , Psicologia do Adolescente , Psicometria , Reprodutibilidade dos Testes , Estudantes/estatística & dados numéricos , Adulto Jovem
11.
Zootaxa ; 3763: 1-62, 2014 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-24870276

RESUMO

Dividing the world into nine regions, this first paper describes literature records of the limno-terrestrial tardigrades (Tardigrada) reported from Central America. Updating previously published species lists we have revised the taxonomy and provided additional habitat, geographic co-ordinates, and biogeographic comments. It is hoped this work will serve as a reference point and background for further zoogeographic studies.


Assuntos
Distribuição Animal , Tardígrados/classificação , Tardígrados/fisiologia , Animais , América Central , Ecossistema
12.
Zootaxa ; 3790: 357-79, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24869872

RESUMO

In four samples of mosses and mosses mixed with lichens collected in the Peruvian region of Cusco, 344 tardigrades, 78 free-laid eggs and six simplexes were found. In total, nine species were identified: Cornechiniscus lobatus, Echiniscus dariae, E. ollantaytamboensis, Isohypsibius condorcanquii sp. nov., Macrobiotus pisacensis sp. nov., Milnesium krzysztofi, Minibiotus intermedius, Paramacrobiotus intii sp. nov. and Pseudechiniscus ramazzottii ramazzottii. Isohypsibius condorcanquii sp. nov. is most similar to I. baldii, but differs mainly by the absence of ventral sculpture, the presence of the oral cavity armature, a different macroplacoid length sequence and a different shape of macroplacoids. The new species also differs from other congeners by a different dorsal sculpture, the absence of cuticular bars under the claws and the absence of eyes. Macrobiotus pisacensis sp. nov. differs from the most similar M. ariekammensis and M. kirghizicus by a different oral cavity armature, the presence of cuticular pores, details of egg morphology and some morphometric characters of both animals and eggs. Paramacrobiotus intii sp. nov. differs from most similar species of the genus by a different type of the oral cavity armature, details of egg morphology and some morphometric characters of both animals and eggs. In addition, we briefly discuss the tardigrade fauna of Peru, and propose a simple and economic system of describing relative lengths of pharyngeal macroplacoids. The system is especially useful in interspecific comparisons and differential diagnoses.


Assuntos
Biodiversidade , Tardígrados/ultraestrutura , Animais , Briófitas , Peru
13.
Emotion ; 24(1): 291-298, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38227472

RESUMO

Comments on the article by Campbell et al. (see record 2021-21096-001). Campbell et al. (2021) claimed motivational intensity (approach-avoidance) is a redundant construct that is merely another label for valence (positive-negative). They based their conclusion on a high correlation between valence and motivational intensity when participants rated pictures. We present arguments that their conclusion was based on inadequate evidence. First, we explain how high correlation fails to identify meaningful and consistent affective states where motivational intensity is essential. As a counterargument, we present replicated and cumulative empirical evidence of differences between affective states with equal valence and arousal but different motivational intensities such as desire or enthusiasm versus amusement. Second, we emphasize that correlations do not account for relative differences between valence and motivational intensity levels (which we termed undermotivated and overmotivated affect). We illustrate this by presenting how valence and motivational intensity diverge during watching affective video clips. We conclude the opposite of Campbell's team, that is, motivational intensity is a viable concept deserving further attention. However, studying motivational intensity requires specific strategies to dissect what is possible within affect from the most frequent. We formulate several recommendations regarding the choice of stimuli (overrepresentation of specific categories) and measurement (e.g., measuring dimensions of affect along with a broad range of discrete emotions and motivational concepts). This might improve the study in affective science toward stronger differentiation within the core of human affect. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Casamento , Motivação , Humanos , Nível de Alerta , Emoções
14.
Heliyon ; 10(5): e26807, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38434295

RESUMO

Desiccation-tolerant organisms can survive dehydration in a state of anhydrobiosis. Tardigrades can recover from anhydrobiosis at any life stage and are considered among the toughest animals on Earth. However, the factors that influence recovery from anhydrobiosis are not well understood. The study aimed to evaluate the effect of sex, age, the presence of other individuals and the combination of the number and duration of anhydrobiosis episodes on the recovery of Paramacrobiotus experimentalis. The activity of 1200 individuals for up to 48 h after rehydration was evaluated using analysis of variance (ANOVA). Age was the main factor influencing return to activity, followed by the combination of number and duration of anhydrobiosis episodes, influence of the presence of other individuals, and sex. More individuals returned to activity after repeated short than repeated long anhydrobiosis episodes and older individuals were less likely to recover than younger individuals. In addition, when compared to single animals, the presence of other individuals resulted in higher number of active animals after dehydration and rehydration. The effect of sex was significant, but there was no general tendency for one sex to recover from anhydrobiosis better than the other one. The results contribute to a better understanding of the anhydrobiosis ability of Paramacrobiotus experimentalis and provide background for full explanation of molecular, cellular and environmental mechanisms of anhydrobiosis.

16.
Life (Basel) ; 14(3)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38541660

RESUMO

Perchlorate salts, including magnesium perchlorate, are highly toxic compounds that occur on Mars at levels far surpassing those on Earth and pose a significant challenge to the survival of life on this planet. Tardigrades are commonly known for their extraordinary resistance to extreme environmental conditions and are considered model organisms for space and astrobiological research. However, their long-term tolerance to perchlorate salts has not been the subject of any previous studies. Therefore, the present study aimed to assess whether the tardigrade species Paramacrobiotus experimentalis can survive and grow in an environment contaminated with high levels of magnesium perchlorates (0.25-1.0%, 1.5-6.0 mM ClO4- ions). The survival rate of tardigrades decreased with an increase in the concentration of the perchlorate solutions and varied from 83.3% (0.10% concentration) to 20.8% (0.25% concentration) over the course of 56 days of exposure. Tardigrades exposed to 0.15-0.25% magnesium perchlorate revealed significantly decreased body length. Our study indicates that tardigrades can survive and grow in relatively high concentrations of magnesium perchlorates, largely exceeding perchlorate levels observed naturally on Earth, indicating their potential use in Martian experiments.

17.
Sci Rep ; 14(1): 5097, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429316

RESUMO

Increasing temperature influences the habitats of various organisms, including microscopic invertebrates. To gain insight into temperature-dependent changes in tardigrades, we isolated storage cells exposed to various temperatures and conducted biochemical and ultrastructural analysis in active and tun-state Paramacrobiotus experimentalis Kaczmarek, Mioduchowska, Poprawa, & Roszkowska, 2020. The abundance of heat shock proteins (HSPs) and ultrastructure of the storage cells were examined at different temperatures (20 °C, 30 °C, 35 °C, 37 °C, 40 °C, and 42 °C) in storage cells isolated from active specimens of Pam. experimentalis. In the active animals, upon increase in external temperature, we observed an increase in the levels of HSPs (HSP27, HSP60, and HSP70). Furthermore, the number of ultrastructural changes in storage cells increased with increasing temperature. Cellular organelles, such as mitochondria and the rough endoplasmic reticulum, gradually degenerated. At 42 °C, cell death occurred by necrosis. Apart from the higher electron density of the karyoplasm and the accumulation of electron-dense material in some mitochondria (at 42 °C), almost no changes were observed in the ultrastructure of tun storage cells exposed to different temperatures. We concluded that desiccated (tun-state) are resistant to high temperatures, but not active tardigrades (survival rates of tuns after 24 h of rehydration: 93.3% at 20 °C, 60.0% at 35 °C, 33.3% at 37 °C, 33.3% at 40 °C, and 20.0% at 42 °C).


Assuntos
Tardígrados , Animais , Temperatura , Tardígrados/metabolismo , Proteínas de Choque Térmico/metabolismo , Invertebrados/metabolismo , Proteínas de Choque Térmico HSP70 , Temperatura Alta
18.
Materials (Basel) ; 17(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38255528

RESUMO

This article presents the results of petrophysical analyses of limestones and sandstones used for the construction of the wall structures of a Roman rural settlement located in Podsilo Bay on Rab Island (Croatia). An on-site analysis of the walls indicated the use of different lithotypes, which is an uncommon case in the area. So far, no petrophysical properties of the applied materials have been tested, and their provenance has not been specified. The aim of this research was to determine their usability as construction materials in an attempt to determine the possible reasons behind the usage of multiple lithotypes and their suitability as building materials. The following procedure was used to address these issues: (1) determination of the petrographic characteristics of the rocks, (2) performance of tests to characterise the mechanical properties in a complex stress state of uniaxial tension followed by uniaxial and triaxial compression, and, finally, (3) determination of the internal structure of the rocks using methods based on X-ray imaging. Multi-proxy characteristics of the materials including numerous observations and methods were performed: optical microscopy used to characterise rock petrography and mineralogy, scanning electron microscopy (SEM) coupled with EDS, as well as grinding tests; furthermore, mechanical properties were determined on cylindrical samples in accordance with European standards. X-ray microtomography using the XµCT method enabled microscopic observations and determination of the orientation of discontinuities and the rock structure. The performed analyses allowed us to distinguish three lithological types of sandstone and two types of limestone among the examined stone blocks. Stone blocks of fine- and medium-grained sandstone with carbonate binders, as well as sparitic limestone and mudstone with calcite veins, were used to build the studied structures. The analysed blocks showed traces of partial edge processing. Despite the defects in the material structure identified using XµCT, all the types of rock were characterised by high or very high strength. High values of longitudinal wave velocity confirmed the good quality of the material. These results contribute to a better understanding of the construction process and the related technological choices, and they provide the first dataset which can be used for the reconstruction of the building's original appearance in the future.

19.
Molecules ; 18(12): 15344-56, 2013 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-24335615

RESUMO

In this article the crystal structures of the starting material TZ-5 and the key intermediate TZ-6 of temozolomide (TZ-7), an anticancer therapeutic agent, are presented, together with their spectroscopic and thermal characteristics. Both compounds crystallize in the triclinic P-1 space group. X-ray crystallography studies proved that the compound TZ-6 exists as a monohydrate. A complete structural assignment was obtained for the signals in the 1H-, 13C- and 15N-nuclear magnetic resonance spectra and the structures were confirmed by Fourier-Transform infrared and Raman spectroscopy. The article describes the importance of the high purity of TZ-6 during the small-scale plant production of TZ-7 in a desired polymorphic form III with the purity higher than 99.50%, according to an HPLC method.


Assuntos
Dacarbazina/análogos & derivados , Antineoplásicos Alquilantes/química , Antineoplásicos Alquilantes/normas , Cristalografia por Raios X , Dacarbazina/química , Dacarbazina/normas , Modelos Moleculares , Conformação Molecular , Ressonância Magnética Nuclear Biomolecular , Análise Espectral Raman , Temozolomida , Termodinâmica
20.
Biomed Pharmacother ; 158: 114063, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36495665

RESUMO

Tardigrades are ubiquitous microinvertebrates exhibiting extreme tolerance to various environmental stressors like low and high temperatures, lack of water, or high radiation. Although exact pathways behind the tardigrade extremotolerance are yet to be elucidated, some molecules involved have been identified. Their evidenced properties may lead to novel opportunities in biomedical and pharmacological development. This review aims to present the general characteristics of tardigrade intrinsically disordered proteins (TDPs: Dsup, CAHS, SAHS, MAHS) and late embryogenesis-abundant proteins (LEA) and provide an updated overview of their features and relevance for potential use in biomedicine and pharmacology. The Dsup reveals a promising action in attenuating oxidative stress, DNA damage, and pyrimidine dimerization, as well as increasing radiotolerance in transfected human cells. Whether Dsup can perform these functions when delivered externally is yet to be understood by in vivo preclinical testing. In turn, CAHS and SAHS demonstrate properties that could benefit the preservation of pharmaceuticals (e.g., vaccines) and biomaterials (e.g., cells). Selected CAHS proteins can also serve as inspiration for designing novel anti-apoptotic agents. The LEA proteins also reveal promising properties to preserve desiccated biomaterials and can act as anti-osmotic agents. In summary, tardigrade molecules reveal several potential biomedical applications advocating further research and development. The challenge of extracting larger amounts of these molecules can be solved with genetic engineering and synthetic biology tools. With new species identified each year and ongoing studies on their extremotolerance, progress in the medical use of tardigrade proteins is expected shortly.


Assuntos
Tardígrados , Humanos , Animais , Tardígrados/genética , Tardígrados/metabolismo , Proteínas/metabolismo , Dano ao DNA
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