scholarly journals The role of the pre-Alpine polycrystalline basement in the paleogeographic configuration of multiple Neotethyan oceanic basins

Geologija ◽  
2021 ◽  
Vol 64 (2) ◽  
pp. 143-158
Author(s):  
Darko SPAHIĆ ◽  
Tivadar GAUDENYI
Keyword(s):  
Late Jurassic ◽  
Temporal Relationship ◽  
Spatial Arrangement ◽  
Published Data ◽  
Plate Tectonic ◽  
Vardar Zone ◽  
Early Mesozoic ◽  
Spatial Alignment ◽  
Variscan Basement

The study provides a deeper understanding of the early Mesozoic paleogeogeographic spatial-temporal relationship by studying the two Adria-Europe intervening basement blocks. The Drina-Ivanjica and Pelagonian crustal fragments play important role in the internal early Alpine oceanic constitution further controlling the late Jurassic emplacement of Tethyan Dinaric-Hellenic ophiolites. The proposed paleogeographic reassessment is driven by the new paleocontinental inheritance data associated with the Variscan – pre-Variscan basement terranes. The recently published data suggest an Avalonian-type inheritance of the Pelagonian basement block which indicates a different pre-Variscan plate-tectonic journey, including separate spatial arrangement during Variscan amalgamation. In turn, Cadomian-type basement inheritance has been documented within the sliced Adria microplate. Thus, the Avalonian inheritance place the Pelagonian block away from the Apulia/Adria (Dinarides). In the investigated context of Paleozoic-Mesozoic paleogeographic transition, the Pelagonian block may represent a segment of the Cimmerian ribbon continent or southernmost segment of the Variscan Europe. With regards the nearby Adria microplate, a Triassic-Jurassic oceanic opening led to the decoupling (spreading away from the main Adria microplate) of the Drina-Ivanjica block. The rifting is in line with the simultaneous yet opposite or westward-directed drift of the Pelagonides. The breakup of south European Variscan configuration eventually result in the spatial alignment of the two basement fragments referred to as the “Drina–Pelagonide continental splinter”. By linking the paleogeographic pre-Jurassic–Jurassic relationship between these continental units, the two landlocked Neotethyan Vardar s.l. basins are extrapolated, “Dinaric Tethys” / Inner Dinaric-(Mirdita-Pindos) and the main Vardar Ocean (Western Vardar Zone).

Geometric Factor in Skeletal Reactions of 2-Methylpentane on Stepped Surfaces of Platinum Catalyst

1992 ◽  
Vol 57 (10) ◽  
pp. 2012-2020
Author(s):  
Vladimír Hejtmánek
Keyword(s):  
Active Sites ◽  
Platinum Catalyst ◽  
Point Of View ◽  
Geometric Factor ◽  
Published Data ◽  
Stepped Surfaces ◽  
Geometric Conditions ◽  
Surface Intermediates ◽  
Isomerization Mechanism

The role of geometric factor in the course of skeletal reactions (isomerization, hydrogenolysis) of 2-methylpentane on stepped (119), (557) and reconstructed R(557) surfaces of single crystals of platinum was evaluated with computer designed models. These calculations were compared with reported experimental data. It was found by analysis of geometric conditions that there are accessible active ensembles on double step of the reconstructed R(557) surface. In addition, these active sites are unsaturated in their coordination sphere and thus catalytically effective. This finding is consistent with published data, confirming higher catalytic activity of this surface. The various pathways of Bond Shift isomerization mechanism of 2-methylpentane from the point of view of steric demands of surface intermediates on differently located ensembles are discussed, too.

scholarly journals Overview on the Different Patterns of Tumor Vascularization

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 639
Author(s):  
Domenico Ribatti ◽  
Francesco Pezzella
Keyword(s):  
Vasculogenic Mimicry ◽  
Endothelial Cell Proliferation ◽  
Published Data ◽  
Alternative Mechanism ◽  
Tumor Vascularization ◽  
Angiogenic Therapy ◽  
Physiological Processes ◽  
Inhibition Of Angiogenesis ◽  
Therapeutic Development

Angiogenesis is a crucial event in the physiological processes of embryogenesis and wound healing. During malignant transformation, dysregulation of angiogenesis leads to the formation of a vascular network of tumor-associated capillaries promoting survival and proliferation of the tumor cells. Starting with the hypothesis formulated by Judah Folkman that tumor growth is angiogenesis-dependent, this area of research has a solid scientific foundation and inhibition of angiogenesis is a major area of therapeutic development for the treatment of cancer. Over this period numerous authors published data of vascularization of tumors, which attributed the cause of neo-vascularization to various factors including inflammation, release of angiogenic cytokines, vasodilatation, and increased tumor metabolism. More recently, it has been demonstrated that tumor vasculature is not necessarily derived by endothelial cell proliferation and sprouting of new capillaries, but alternative vascularization mechanisms have been described, namely vascular co-option and vasculogenic mimicry. In this article, we have analyzed the mechanisms involved in tumor vascularization in association with classical angiogenesis, including post-natal vasculogenesis, intussusceptive microvascular growth, vascular co-option, and vasculogenic mimicry. We have also discussed the role of these alternative mechanism in resistance to anti-angiogenic therapy and potential therapeutic approaches to overcome resistance.

The Need for Consensus About Liver Transplantation For Patients With Neuropsychiatric Wilson’s Disease

2021 ◽  
pp. 152692482110028
Author(s):  
Alberto Ferrarese ◽  
Patrizia Burra
Keyword(s):  
Liver Transplantation ◽  
Patient Outcomes ◽  
Wilson’S Disease ◽  
Therapeutic Option ◽  
Copper Metabolism ◽  
Wilson's Disease ◽  
Published Data ◽  
Neurological Improvement ◽  
Effective Therapeutic Option

Liver transplantation is considered an effective therapeutic option for Wilson’s disease (WD) patients with hepatic phenotype, since it removes the inherited defects of copper metabolism, and is associated with excellent graft and patient outcomes. The role of liver transplantation in WD patients with mixed hepatic and neuropsychiatric phenotype has remained controversial over time, mainly because of high post-operative complications, reduced survival and a variable, unpredictable rate of neurological improvement. This article critically discusses the recently published data in this field, focussing in more detail on isolated neuropsychiatric phenotype as a potential indication for liver transplantation in WD patients.

scholarly journals Novel Insights on the Role of Nitric Oxide in the Ovary: A Review of the Literature

2021 ◽  
Vol 18 (3) ◽  
pp. 980
Author(s):  
Maria Cristina Budani ◽  
Gian Mario Tiboni
Keyword(s):  
Nitric Oxide ◽  
In Vivo Studies ◽  
Published Data ◽  
Vitro Fertilization ◽  
Peripheral Neurons ◽  
Relevant Role ◽  
Oocyte Meiotic Maturation

Nitric oxide (NO) is formed during the oxidation of L-arginine to L-citrulline by the action of multiple isoenzymes of NO synthase (NOS): neuronal NOS (nNOS), endotelial NOS (eNOS), and inducible NOS (iNOS). NO plays a relevant role in the vascular endothelium, in central and peripheral neurons, and in immunity and inflammatory systems. In addition, several authors showed a consistent contribution of NO to different aspects of the reproductive physiology. The aim of the present review is to analyse the published data on the role of NO within the ovary. It has been demonstrated that the multiple isoenzymes of NOS are expressed and localized in the ovary of different species. More to the point, a consistent role was ascribed to NO in the processes of steroidogenesis, folliculogenesis, and oocyte meiotic maturation in in vitro and in vivo studies using animal models. Unfortunately, there are few nitric oxide data for humans; there are preliminary data on the implication of nitric oxide for oocyte/embryo quality and in-vitro fertilization/embryo transfer (IVF/ET) parameters. NO plays a remarkable role in the ovary, but more investigation is needed, in particular in the context of human ovarian physiology.

scholarly journals The Biochemical Diagnosis of Acromegaly

2021 ◽  
Vol 10 (5) ◽  
pp. 1147
Author(s):  
Amit Akirov ◽  
Hiba Masri-Iraqi ◽  
Idit Dotan ◽  
Ilan Shimon
Keyword(s):  
English Language ◽  
Diagnostic Delay ◽  
Tolerance Test ◽  
Oral Glucose ◽  
Published Data ◽  
Biochemical Diagnosis ◽  
Key Factor ◽  
Assay Methods ◽  
Serum Gh

Background: The diagnosis of acromegaly still poses a clinical challenge, and prolonged diagnostic delay is common. The most important assays for the biochemical diagnosis and management of acromegaly are growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Objective: Discuss the role of IGF-1, basal serum GH, and nadir GH after oral glucose tolerance test (OGTT) for the diagnosis, management, and treatment of patients with acromegaly. Methods: We performed a narrative review of the published data on the biochemical diagnosis and monitoring of acromegaly. An English-language search for relevant studies was conducted on PubMed from inception to 1 January 2021. The reference lists of relevant studies were also reviewed. Results: Serum IGF-1 levels, basal GH values, and nadir GH after OGTT play a major role in the diagnosis, management, and treatment of patients with acromegaly. Measurement of IGF-1 levels is the key factor in the diagnosis and monitoring of acromegaly, but basal and nadir GH following OGTT are also important. However, several factors may significantly influence the concentrations of these hormones, including assay methods, physiologic and pathologic factors. In some cases, discordant GH and IGF-1 levels may be challenging and usually requires additional data and monitoring. Conclusion: New GH and IGF-1 standards are much more precise and provide more accurate tools to diagnose and monitor patients with acromegaly. However, all these biochemical tools have their limitations, and these should be taken under consideration, along with the history, clinical features and imaging studies, when assessing patients for acromegaly.

Platelet Glycoprotein Receptor IIIa Polymorphism PlA1/PlA2 and Coronary Risk: a Meta-Analysis

2001 ◽  
Vol 85 (04) ◽  
pp. 626-633 ◽  
Author(s):  
Augusto Di Castelnuovo ◽  
Giovanni de Gaetano ◽  
Maria Benedetta Donati ◽  
Licia Iacoviello
Keyword(s):  
Odds Ratio ◽  
Meta Analysis ◽  
Platelet Glycoprotein ◽  
Published Data ◽  
Coronary Risk ◽  
Gene Encoding ◽  
Glycoprotein Iiia ◽  
Artery Disease ◽  
Revascularization Procedures

SummaryMembrane glycoprotein IIb/IIIa plays a major role in platelet function. The gene encoding the glycoprotein IIIa shows a common polymorphism PlA1/PlA2 that was variably associated with vascular disease. To clarify the role of PlA1/PlA2 polymorphism in coronary risk, a meta-analysis of published data was conducted. Studies were identified both by MEDLINE searches, and hand searching of journals and abstract books.A total of 34 studies for coronary artery disease (CAD), and 6 for restenosis after revascularization were identified, for a total of 9,095 cases and 12,508 controls. In CAD, the overall odds ratio for carriers of the PlA2 allele was 1.10 (95% CI: 1.03 to 1.18), and it was 1.21 (95% CI: 1.05 to 1.38) in subjects younger than 60. Overall odds ratio was 1.31 (95% CI: 1.10 to 1.56) after revascularization procedures.The association of PlA2 status with overall cardiovascular disease in the general population is significant but weak; higher risk has been identified in less heterogeneous subgroups as in the younger cohorts and in the restenosis subset with stents.

scholarly journals The Role of RNA in DNA Breaks, Repair and Chromosomal Rearrangements

Biomolecules ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 550
Author(s):  
Matvey Mikhailovich Murashko ◽  
Ekaterina Mikhailovna Stasevich ◽  
Anton Markovich Schwartz ◽  
Dmitriy Vladimirovich Kuprash ◽  
Aksinya Nicolaevna Uvarova ◽  
...  
Keyword(s):  
Chromosomal Rearrangements ◽  
Gene Mutations ◽  
Nonhomologous End Joining ◽  
Published Data ◽  
Dna Double Strand Breaks ◽  
Dna Breaks ◽  
End Joining ◽  
Homology Directed Repair ◽  
Chromosome Aberration Frequency

Incorrect reparation of DNA double-strand breaks (DSB) leading to chromosomal rearrangements is one of oncogenesis’s primary causes. Recently published data elucidate the key role of various types of RNA in DSB formation, recognition and repair. With growing interest in RNA biology, increasing RNAs are classified as crucial at the different stages of the main pathways of DSB repair in eukaryotic cells: nonhomologous end joining (NHEJ) and homology-directed repair (HDR). Gene mutations or variation in expression levels of such RNAs can lead to local DNA repair defects, increasing the chromosome aberration frequency. Moreover, it was demonstrated that some RNAs could stimulate long-range chromosomal rearrangements. In this review, we discuss recent evidence demonstrating the role of various RNAs in DSB formation and repair. We also consider how RNA may mediate certain chromosomal rearrangements in a sequence-specific manner.

Fine Structure of Swarmers of Cladophora and Chaetomorpha

1971 ◽  
Vol 9 (3) ◽  
pp. 581-601
Author(s):  
D. G. ROBINSON ◽  
R. D. PRESTON
Keyword(s):  
Cell Wall ◽  
Fine Structure ◽  
Spatial Arrangement ◽  
Cell Wall Synthesis ◽  
Fibrous Layer ◽  
Etching Technique ◽  
Freeze Etching

Naked swarmers of both Cladophora rupestris and Chaetomorpha melagonium have been examined by the freeze-etching technique. The swarmers of Cladophora, collected just after settling, reveal several layers of granules external to the plasmalemma and internal to the so-called ‘fibrous-layer’. Chaetomorpha swarmers collected just before settling show extrusion of vesicles through the plasmalemma. The structures associated with the membranes are discussed in relation to known features of these swarmers already observed by sectioning. The role of granules in the synthesis of cell wall microfibrils is strengthened though the spatial arrangement of the granules seen in this investigation does not completely fulfil the ‘ordered granule’ hypothesis. Description of, and comments on, features related to cell wall synthesis, particularly the Golgi and vacuolar systems, are given.

Oralizations in e-mail consultations: A study of general practitioners’ use of non-verbal cues in written doctor–patient communication

2021 ◽  
Vol 13 (2) ◽  
pp. 195-211
Author(s):  
Maja Nordtug ◽  
Jane Ege Møller ◽  
Signe Schlichting Matthiesen ◽  
Matilde Nisbeth Brøgger
Keyword(s):  
General Practitioners ◽  
Facial Expressions ◽  
Eye Contact ◽  
Spatial Arrangement ◽  
Patient Communication ◽  
Verbal Cues ◽  
Spelling Errors ◽  
Doctor Patient Communication ◽  
E Mail

It is well-known that non-verbal cues are essential in doctor–patient communication. As doctor–patient communication is turning increasingly digital and written, it becomes relevant to explore the role of non-verbal cues in such communication genres. One more recent genre is the doctor–patient e-mail consultation. Research has found that while patients like e-mail consultations, they also miss facial expressions, eye contact, etc. In this study, we explored the different ways in which Danish GPs use non-verbal cues in e-mail consultations. We analysed 633 e-mail consultations written by 22 GPs. We applied the concept of oralization, which includes the use of emoticons and non-standard use of grammar and spatial arrangement. We found that the dominant types of oralizations were non-corrected spelling errors and lack of attention to capitalization. Overall, GPs used a limited number of other non-verbal cues. We discuss how these findings relate to norms of formality and professional context.

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