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1.
Molecules ; 27(7)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35408758

RESUMO

ß-Hydroxy sulfones are important in organic synthesis. The simplest method of ß-hydroxy sulfones synthesis is the hydrogenation of ß-keto sulfones. Herein, we report the reducing properties of alkyl aluminum compounds R3Al (R = Et, i-Bu, n-Bu, t-Bu and n-Hex); i-Bu2AlH; Et2AlCl and EtAlCl2 in the hydrogenation of ß-keto sulfones. The compounds i-Bu2AlH, i-Bu3Al and Et3Al are the at best reducing agents of ß-keto sulfones to ß-hydroxy sulfones. In reactions of ß-keto sulfones with aluminum trialkyls, hydroalumination products with ß-hydroxy sulfone ligands [R2AlOC(C6H5)CH2S(O)2(p-R1C6H4]n [where n = 1,2; 2aa: R = i-Bu, R1 = CH3; 2ab: R = i-Bu, R1 = Cl; 2ba: R = Et, R1 = CH3; 2bb: R = Et, R1 = Cl] and {[Et2AlOC(C6H5)CH2S(O)2(p-ClC6H4]∙Et3Al}n3bb were obtained. These complexes in the solid state have a dimeric structure, while in solutions, they appear as equilibrium monomer-dimer mixtures. The hydrolysis of both the isolated 2aa, 2ab, 2ba, 2bb and 3bb and the postreaction mixtures quantitatively leads to pure racemic ß-hydroxy sulfones. Hydroalumination reaction of ß-keto sulfones with alkyl aluminum compounds and subsequent hydrolysis of the complexes is a simple and very efficient method of ß-hydroxy sulfones synthesis.


Assuntos
Alumínio , Sulfonas , Alumínio/química , Compostos de Alumínio , Hidrogenação , Estrutura Molecular , Sulfonas/química
2.
Glob Chang Biol ; 22(5): 1710-21, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26919067

RESUMO

Recent palaeogenetic studies indicate a highly dynamic history in collared lemmings (Dicrostonyx spp.), with several demographical changes linked to climatic fluctuations that took place during the last glaciation. At the western range margin of D. torquatus, these changes were characterized by a series of local extinctions and recolonizations. However, it is unclear whether this pattern represents a local phenomenon, possibly driven by ecological edge effects, or a global phenomenon that took place across large geographical scales. To address this, we explored the palaeogenetic history of the collared lemming using a next-generation sequencing approach for pooled mitochondrial DNA amplicons. Sequences were obtained from over 300 fossil remains sampled across Eurasia and two sites in North America. We identified five mitochondrial lineages of D. torquatus that succeeded each other through time across Europe and western Russia, indicating a history of repeated population extinctions and recolonizations, most likely from eastern Russia, during the last 50 000 years. The observation of repeated extinctions across such a vast geographical range indicates large-scale changes in the steppe-tundra environment in western Eurasia during the last glaciation. All Holocene samples, from across the species' entire range, belonged to only one of the five mitochondrial lineages. Thus, extant D. torquatus populations only harbour a small fraction of the total genetic diversity that existed across different stages of the Late Pleistocene. In North American samples, haplotypes belonging to both D. groenlandicus and D. richardsoni were recovered from a Late Pleistocene site in south-western Canada. This suggests that D. groenlandicus had a more southern and D. richardsoni a more northern glacial distribution than previously thought. This study provides significant insights into the population dynamics of a small mammal at a large geographical scale and reveals a rather complex demographical history, which could have had bottom-up effects in the Late Pleistocene steppe-tundra ecosystem.


Assuntos
Arvicolinae/genética , Extinção Biológica , Variação Genética , Animais , Regiões Árticas , DNA Antigo/análise , DNA Mitocondrial/análise , Europa (Continente) , Fósseis , Pradaria , América do Norte , Filogenia , Dinâmica Populacional , Federação Russa , Análise de Sequência de DNA , Tundra
3.
Postepy Hig Med Dosw (Online) ; 69: 905-12, 2015 Aug 11.
Artigo em Polonês | MEDLINE | ID: mdl-26270517

RESUMO

Surgical and endovascular revascularization of ischemic legs in patients with peripheral arterial disease (PAD) can damage the arterial wall (endothelial and smooth muscle cells). Hemostatic factors released during endothelial dysfunction can lead to restenosis. 1. Determination of selected endothelial hemostatic factors in PAD patients and a reference group. 2. Prospective observation of new restenosis appearance in PAD patients after endovascular revascularization. 3. Comparison of selected endothelial hemostatic factors between non-restenotic and restenotic PAD patients. 150 PAD patients after endovascular revascularization - 90 men and 60 women, aged 44-88 (mean 65.5) years - were examined. During one-year observation after the revascularization procedures in 38 PAD patients restenosis occurred, when blood samples were also collected. The reference group consisted of 53 healthy persons - 44 men and 9 women, aged 20-56 years. Blood was drawn in the morning into 3.2% sodium citrate at a ratio of 9:1. Tissue factor (TF), tissue factor pathway inhibitor (TFPI), thrombomodulin (TM), von Willebrand factor (vWF) and tissue plasminogen activator (t-PA) were measured in plasma with commercial tests using the enzyme immunoassay. In the plasma of PAD patients after revascularization, the concentrations of TF and vWF were significantly higher, TM lower, TFPI and t-PA similar compared to the reference group. Six months after revascularization the level of TF had increased and vWF had significantly decreased. The endothelial hemostatic factors before and after restenosis did not significantly differ except TF, which after restenosis was higher. Increased TF and vWF levels in PAD patients indicate arterial endothelial cell damage, by atherosclerotic and revascularization processes. In PAD patients with restenosis compared to these patients before restenosis the determined endothelial hemostatic factors, except TF level, did not significantly differ. Perhaps TF participates in restenosis formation.


Assuntos
Biomarcadores/sangue , Reestenose Coronária/complicações , Endotélio Vascular/metabolismo , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Intervenção Coronária Percutânea/efeitos adversos , Doença Arterial Periférica/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Perna (Membro)/cirurgia , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/patologia , Estudos Prospectivos
4.
Materials (Basel) ; 17(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38894025

RESUMO

Aluminum garnets display exceptional adaptability in incorporating mismatching elements, thereby facilitating the synthesis of novel materials with tailored properties. This study explored Ce3+-doped Tb3Al5-xScxO12 crystals (where x ranges from 0.5 to 3.0), revealing a novel approach to control luminescence and photoconversion through atomic size mismatch engineering. Raman spectroscopy confirmed the coexistence of garnet and perovskite phases, with Sc substitution significantly influencing the garnet lattice and induced A1g mode softening up to Sc concentration x = 2.0. The Sc atoms controlled sub-eutectic inclusion formation, creating efficient light scattering centers and unveiling a compositional threshold for octahedral site saturation. This modulation enabled the control of energy transfer dynamics between Ce3+ and Tb3+ ions, enhancing luminescence and mitigating quenching. The Sc admixing process regulated luminous efficacy (LE), color rendering index (CRI), and correlated color temperature (CCT), with adjustments in CRI from 68 to 84 and CCT from 3545 K to 12,958 K. The Ce3+-doped Tb3Al5-xScxO12 crystal (where x = 2.0) achieved the highest LE of 114.6 lm/W and emitted light at a CCT of 4942 K, similar to daylight white. This approach enables the design and development of functional materials with tailored optical properties applicable to lighting technology, persistent phosphors, scintillators, and storage phosphors.

5.
J Biomol Struct Dyn ; 39(13): 4845-4858, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32579069

RESUMO

In this study, five new complexes containing deferiprone (dfp) and N,N-donor ligands [bipyridine (bpy), 1,10-phenanthroline (phen) and ethylenediamine (en)] were synthesized: [Fe(dfp)2(bpy)](PF6) (1), [Fe(dfp)2(phen)](PF6) (2), [Cu2(dfp)2(bpy)2](PF6)2 (3), [Ga(dfp)2(bpy)](PF6) (4), and [Fe(dfp)2(en)](PF6) (5). Characterization of these complexes was carried out through elemental analysis and FT-IR, and single-crystal X-ray crystallography was used to determine their structures. Whilst the polyhedron has a distorted octahedral geometry in 1, 2, 4, and 5, it adopts a distorted square-pyramidal geometry in 3. Interaction of these compounds with human serum albumin (HSA) has been investigated through electronic absorption and fluorescence titration techniques. Emission quenching was performed separately for each complex at three different temperatures and thermodynamic parameters were calculated using binding constants to better understand the power of different binding forces with the HSA. Results demonstrated that compounds interact strongly with the HSA with a static quenching mechanism. Our evaluation of the cytotoxicity of complexes against the breast cancer MCF-7 cell line showed that complex 2 presents a better cytotoxicity than the standard cis-Pt. Finally, using the AutoDock 4.2 program, simulations to analyze the mechanism of complex-HSA interactions and their binding mode were carried out. Results showed that the best binding mode is located in subdomain IB for 1, 2, and 4, in I/II for 3, and in IA/IIA for 5. Communicated by Ramaswamy H. Sarma.


Assuntos
Antineoplásicos , Neoplasias da Mama , Complexos de Coordenação , Antineoplásicos/farmacologia , Sítios de Ligação , Complexos de Coordenação/farmacologia , DNA/metabolismo , Deferiprona , Feminino , Humanos , Ligantes , Células MCF-7 , Ligação Proteica , Albumina Sérica Humana/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Sci Rep ; 11(1): 22078, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34837003

RESUMO

Evidence of mobiliary art and body augmentation are associated with the cultural innovations introduced by Homo sapiens at the beginning of the Upper Paleolithic. Here, we report the discovery of the oldest known human-modified punctate ornament, a decorated ivory pendant from the Paleolithic layers at Stajnia Cave in Poland. We describe the features of this unique piece, as well as the stratigraphic context and the details of its chronometric dating. The Stajnia Cave plate is a personal 'jewellery' object that was created 41,500 calendar years ago (directly radiocarbon dated). It is the oldest known of its kind in Eurasia and it establishes a new starting date for a tradition directly connected to the spread of modern Homo sapiens in Europe.

7.
Naturwissenschaften ; 97(4): 411-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20107973

RESUMO

An upper second permanent molar from a human was found alongside numerous tools of the Micoquian tradition and was excavated in Stajnia Cave, which is located over 100 km North of the Carpathian Mountains in southern Poland. The age of these finds has been established within a time-span of late Saalian to early Weichselian, most likely to OIS 5c or 5a, according to the palaeontological, geological, archaeological and absolute dating of the layer from which they were obtained. An examination of the morphology of the human molar indicates that this tooth exhibits many traits frequently occurring in Neanderthal upper molars. Although the occurrence of derived Neanderthal traits in the Stajnia molar cannot be firmly established because of degradation of its cusps, the presence of the above-mentioned features allows the assertion that this tooth belonged to a Neanderthal. The age of the Stajnia tooth and the archaeological context of this find also indicate that this molar is of Neanderthal origin.


Assuntos
Fósseis , Dente Molar/anatomia & histologia , Dente/anatomia & histologia , DNA Mitocondrial/genética , Oclusão Dentária , Humanos , Maxila/anatomia & histologia , Microscopia Eletrônica de Varredura , Paleontologia , Polônia , Dente/ultraestrutura
8.
Sci Rep ; 10(1): 14778, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901061

RESUMO

The Micoquian is the broadest and longest enduring cultural facies of the Late Middle Palaeolithic that spread across the periglacial and boreal environments of Europe between Eastern France, Poland, and Northern Caucasus. Here, we present new data from the archaeological record of Stajnia Cave (Poland) and the paleogenetic analysis of a Neanderthal molar S5000, found in a Micoquian context. Our results demonstrate that the mtDNA genome of Stajnia S5000 dates to MIS 5a making the tooth the oldest Neanderthal specimen from Central-Eastern Europe. Furthermore, S5000 mtDNA has the fewest number of differences to mtDNA of Mezmaiskaya 1 Neanderthal from Northern Caucasus, and is more distant from almost contemporaneous Neanderthals of Scladina and Hohlenstein-Stadel. This observation and the technological affinity between Poland and the Northern Caucasus could be the result of increased mobility of Neanderthals that changed their subsistence strategy for coping with the new low biomass environments and the increased foraging radius of gregarious animals. The Prut and Dniester rivers were probably used as the main corridors of dispersal. The persistence of the Micoquian techno-complex in South-Eastern Europe infers that this axis of mobility was also used at the beginning of MIS 3 when a Neanderthal population turnover occurred in the Northern Caucasus.


Assuntos
Cavernas , DNA Mitocondrial/análise , Fósseis , Homem de Neandertal/genética , Dente/anatomia & histologia , Animais , Arqueologia , DNA Mitocondrial/genética , Humanos , Homem de Neandertal/classificação , Filogenia , Polônia , Datação Radiométrica , Análise de Sequência de DNA , Dente/fisiologia
12.
Adv Clin Exp Med ; 24(1): 93-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25923092

RESUMO

BACKGROUND: In patients with peripheral artery disease (PAD) a hypercoagulable state and thromboembolic complications occur. Revascularization procedures increase this state, sometimes leading to restenosis. Restenosis following balloon angioplasty (PTA)and stent implantation is ≥ 50% of artery stenosis. OBJECTIVES: To determine the concentration of tissue factor (TF), tissue factor pathway inhibitor (TFPI), thrombin-antithrombin (TAT) complexes, fibrinogen and D-dimers in the blood of patients with PAD after peripheral endovascular revascularization of the lower legs and in PAD patients with restenosis. MATERIAL AND METHODS: The study included 150 patients with PAD, 90 men and 60 women, aged 44-88 (mean 65.5) years, after successful peripheral angioplasty (PTA) and/or with stenting. During the 6 months after the revascularization procedures, restenosis occurred in 27 patients. The reference group consisted of 53 healthy persons (44 men and 9 women, aged 20-56 years). Blood was drawn in the morning into 3.2% natrium citrate at a ratio of 9 : 1. The concentration of TF, TFPI, TAT complexes and D-dimers were measured in plasma with commercial tests using an enzyme immunoassay. Fibrinogen was determined with coagulometer. RESULTS: In the plasma of patients with PAD after endovascular revascularization, the concentrations of TF, TAT complexes, fibrinogen and D-dimers were significantly higher compared to the reference group. During the six months of observation, 27 patients developed restenosis. The results of hemostatic factors in patients with restenosis were compared with the same patients before restenosis and the group of 123 PAD patients after endovascular revascularization. TF and fibrinogen levels in the 27 patients with restenosis were significantly higher than in the group of PAD patients before restenosis. CONCLUSIONS: Statistically significantly higher levels of tissue factor (TF) and fibrinogen in PAD patients with new restenosis, compared to those without restenosis after endovascular revascularization, indicate they can participate in the formation of restenosis.


Assuntos
Fibrinogênio/metabolismo , Oclusão de Enxerto Vascular/diagnóstico , Doença Arterial Periférica/sangue , Tromboplastina/metabolismo , Enxerto Vascular , Adulto , Idoso , Idoso de 80 Anos ou mais , Antitrombina III , Biomarcadores/sangue , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Oclusão de Enxerto Vascular/sangue , Oclusão de Enxerto Vascular/patologia , Oclusão de Enxerto Vascular/cirurgia , Humanos , Perna (Membro)/irrigação sanguínea , Perna (Membro)/patologia , Perna (Membro)/cirurgia , Lipoproteínas/metabolismo , Masculino , Pessoa de Meia-Idade , Peptídeo Hidrolases/sangue , Doença Arterial Periférica/patologia , Doença Arterial Periférica/cirurgia
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