scholarly journals Structural features of the vegetative bodies of Hibiscus syriacus L. (Sev. Malvaceae Juss.) growing under the conditions in Uzbekistan

2021 ◽  
Vol 30 ◽  
pp. 04006
Author(s):  
Abdikhofiz Rakhimov ◽  
Lutfullo Yoziev ◽  
Guljan Duschanova

The article studies the anatomical structure of the vegetative organs, stems, leaves and leaf blades of Hibiscus syriacus L. in Uzbekistan for the first time.

Author(s):  
Z. M. Asadulaev ◽  
◽  
G. A. Sadykova ◽  
Z. R. Ramazanova ◽  
◽  
...  

Identification of the species J. excelsa L. and J. polycarpos C. Koch is problematic and requires addition-al research. This article is devoted to the description and quantification of the anatomical features of the shoots of J. polycarpos, which grows in the conditions of Piedmont Dagestan to solve taxonomic issues. Methods Model shoots (1-3 year old) J. polycarpos was collected from the north side of the crowns at a level of 1.5 m from the ground to study the anatomical structure, fixing, preparing temporary microprepa-rations and describing the main structural elements of shoot tissues was carried out in accordance with generally accepted methods. Results. The anatomical structure of young shoots of J. polycarpos is de-scribed for the first time in order to identify taxon-specific and adaptive characters when studying the ana-tomical structure of the stem of J. excelsa and other populations of J. polycarpos. Their quantitative as-sessment is given, characteristic anatomical features are identified depending on the age and shape of the shoot. Conclusion The specific features of their morphology can be considered the presence of two types of shoots (two-bladed and three-bladed); anatomy - the presence in the parenchyma of leaf pillows in two-bladed shoots of a large number of stony cells, as well as structural features of the central cylinder; the presence and quantity of oil cells. Identified characters can be used for comparative anatomical identifica-tion of species of the genus Juniperus.


2014 ◽  
Vol 48 ◽  
pp. 256-263 ◽  
Author(s):  
O. A. Kataeva

Ramalina sekika Asahina is reported for the first time from Russia from Sakhalin. It refers to the number of rare and poorly investigated species of the genus. Until now it was considered to be endemic to northeastern China. The original description and the location in the Far East are given, as well as the data on anatomical and morphological study of the Russian specimen. The differences in the anatomical structure of its thallus are discussed. A comparison of anatomical and morphological characters of R. sekika, R. pollinaria (Westr.) Ach. (European material), R. yasudae Räsänen has been made; the author considers them as independent species.


Author(s):  
Mavluda Turgunbaevna Yulchieva ◽  
Feruza Madiyarovna Dustmuratova ◽  
Mamlakat Mirganievna Maxmudova ◽  
Makhsuda Usmonkulovna Nizomova

2011 ◽  
Vol 675-677 ◽  
pp. 3-7
Author(s):  
Peter Häussler ◽  
Martin Stiehler

Structure formation, the condensation of a cloud of atoms to a crystal is still not well understood. Disordered sytems (amorphous/liquid) should be in the center of this research, they are the precursors of any crystal. We consider elementary systems, as well as binary, or ternary amorphous alloys, irrespective whether they are metallically, covalently or ionically bonded and describe the process of structure formation in the formal language of thermodynamics but, as far as we know for the first time, by an extended version (general dynamics), based on the complete Gibbs fundamental equation, applied to internal subsystems. Major structural features evolve from global resonances between formerly independent internal subsystems by exchanging momenta and angular momenta, both accompanied by energy. By this they adjust mutually their internal features and create spherical-periodic structural order at medium-range distances. Under the given external constraints the resonances get optimized by selforganization. Global resonances of the type considered have clearly to be distinguished from local resonances between individual ions (described by quantum chemistry) forming local order. The global resonances cause anti-bonding (non-equilibrium) as well as bonding (equilibrium) states of the coupled total system, occupying the latter to form new structurally extended order. The transition to equilibrium creates entropy which itself leaves the system together with energy. At resonance the energetical splitting between the bonding and anti-bonding state is largest, the creation of entropy and the decrease of the total energy therefore, too. The crystal, finally, evolves by additionally optimizing a resonance based on angular momentum, and the additional adjustments of the local resonances to the global ones, theoretically done by applying Bloch’s theorem.


2020 ◽  
Author(s):  
Velio Coviello ◽  
Lucia Capra ◽  
Gianluca Norini ◽  
Norma Dávila ◽  
Dolores Ferrés ◽  
...  

Abstract. The M7.1 Puebla-Morelos earthquake that occurred on 19 September 2017, with epicenter located ∼ 70 km SW from Popocatépetl volcano, severely hit central Mexico. Seismic shaking of the volcanic edifice induced by the earthquake triggered hundreds of shallow landslides on the volcanic flanks, remobilizing loose pyroclastic deposits and saturated soils. The largest landslides occurred on the slopes of aligned ENE-WSW-trending ravines on opposite sides of the volcanic cone, roughly parallel to the regional maximum horizontal stress and local volcanotectonic structural features. This configuration may suggest transient reactivation of local faults and extensional fractures as one of the mechanisms that has weakened the volcanic edifice and promoted the largest slope failures. The seismic records from a broadband station located at few kilometers from the main landslides are used to infer the intensity of ground shaking that triggered the slope failures. The material involved in the larger landslides, mainly ash and pumice fall deposits from late Holocene eruptions with a total volume of about 106 cubic meters, transformed into two large debris flows on the western slope of the volcano and one on its eastern side. The debris flows were highly viscous and contained abundant large woods (about 105 cubic meter). Their peculiar rheology is reconstructed by field evidences and analyzing the grain size distribution of samples from both landslide scars and deposits. This is the first time that such flows were observed at this volcano. Our work provides new insights to constrain a multi-hazard risk assessment for Popocatépetl and other continental active volcanoes.


2020 ◽  
Author(s):  
Chi Zhang ◽  
Stephen Boppart

Abstract The mitochondrion is one of the key organelles for maintaining cellular homeostasis. External environmental stimuli and internal regulatory processes alter the metabolism and functions of mitochondria. To understand these activities of mitochondria, it is critical to probe the key metabolic molecules inside these organelles. In this study, we used label-free chemical imaging modalities including coherent anti-Stokes Raman scattering and multiphoton-excited autofluorescence to study the mitochondrial activities in living cancer cells. We found that hypothermia exposure tends to induce fatty-acid (FA) accumulation in some mitochondria of MIAPaCa-2 cells. Autofluorescence images show that the FA-accumulated mitochondria also have abnormal NADH and FAD metabolism, likely induced by the dysfunction of the electron transport chain. We also found that when the cells were re-warmed to physiological temperature after a period of hypothermia, the FA-accumulated mitochondria changed their structural features, likely caused by the mitophagy process. To the best of our knowledge, this is the first time that FA accumulation in mitochondria was observed in live cells. Our research also demonstrates that multimodal label-free chemical imaging is an attractive tool to discover abnormal functions of mitochondria at the single-organelle level and can be used to quantify the dynamic changes of this organelle under perturbative conditions.


Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3277 ◽  
Author(s):  
Noemi Veraldi ◽  
Alessandro Parra ◽  
Elena Urso ◽  
Cesare Cosentino ◽  
Manuela Locatelli ◽  
...  

Multiple osteochondromas (MO) is a hereditary disorder associated with benign cartilaginous tumors, known to be characterized by absence or highly reduced amount of heparan sulfate (HS) in the extracellular matrix of growth plate cartilage, which alters proper signaling networks leading to improper bone growth. Although recent studies demonstrated accumulation of HS in the cytoplasm of MO chondrocytes, nothing is known on the structural alterations which prevent HS from undergoing its physiologic pathway. In this work, osteochondroma (OC), peripheral chondrosarcoma, and healthy cartilaginous human samples were processed following a procedure previously set up to structurally characterize and compare HS from pathologic and physiologic conditions, and to examine the phenotypic differences that arise in the presence of either exostosin 1 or 2 (EXT1 or EXT2) mutations. Our data suggest that HS chains from OCs are prevalently below 10 kDa and slightly more sulfated than healthy ones, whereas HS chains from peripheral chondrosarcomas (PCSs) are mostly higher than 10 kDa and remarkably more sulfated than all the other samples. Although deeper investigation is still necessary, the approach here applied pointed out, for the first time, structural differences among OC, PCS, and healthy HS chains extracted from human cartilaginous excisions, and could help in understanding how the structural features of HS are modulated in the presence of pathological situations also involving different tissues.


2008 ◽  
Vol 68 (1) ◽  
pp. 149-154 ◽  
Author(s):  
AF. Carvalho ◽  
MS. Santos-Neto ◽  
HSA. Monteiro ◽  
SM. Freitas ◽  
L. Morhy ◽  
...  

Guanylin and uroguanylin are small cysteine-rich peptides involved in the regulation of fluid and electrolyte homeostasis through binding and activation of guanylyl cyclases signaling molecules expressed in intestine and kidney. Guanylin is less potent than uroguanylin as a natriuretic agent and is degraded in vitro by chymotrypsin due to unique structural features in the bioactive moiety of the peptide. Thus, the aim of this study was to verify whether or not guanylin is degraded by chymotrypsin-like proteases present in the kidney brush-border membranes. The isolated perfused rat kidney assay was used in this regard. Guanylin (0.2 µM) induced no changes in kidney function. However, when pretreated by the black-eyed pea trypsin and chymotrypsin inhibitor (BTCI - 1.0 µM; guanylin - 0.2 µM) it promoted increases in urine flow (deltaUF of 0.25 ± 0.09 mL.g-1/min, P < 0.05) and Na+ excretion (% delta ENa+ of 18.20 ± 2.17, P < 0.05). BTCI (1.0 µM) also increased %ENa+ (from 22.8 ± 1.30 to 34.4 ± 3.48, P < 0.05, 90 minutes). Furthermore, BTCI (3.0 µM) induced increases in glomerular filtration rate (GFR; from 0.96 ± 0.02 to 1.28 0.02 mL.g-1/min, P < 0.05, 60 minutes). The present paper strongly suggests that chymotrypsin-like proteases play a role in renal metabolism of guanylin and describes for the first time renal effects induced by a member of the Bowman-Birk family of protease inhibitors.


2003 ◽  
Vol 373 (3) ◽  
pp. 987-992 ◽  
Author(s):  
Eng-Kiat LIM ◽  
Gillian S. HIGGINS ◽  
Yi LI ◽  
Dianna J. BOWLES

Caffeic acid is a phenylpropanoid playing an important role in the pathways leading to lignin synthesis and the production of a wide variety of secondary metabolites. The compound is also an antioxidant and has potential utility as a general protectant against free radicals. Three glucosylated forms of caffeic acid are known to exist: the 3-O- and 4-O-glucosides and the glucose ester. This study describes for the first time a glucosyltransferase [UDP-glucose:glucosyltransferase (UGT)] that is specific for the 3-hydroxyl, and not the 4-hydroxyl, position of caffeic acid. The UGT sequence of Arabidopsis, UGT71C1, has been expressed as a recombinant fusion protein in Escherichia coli, purified and assayed against a range of substrates in vitro. The assay confirmed that caffeic acid as the preferred substrate when compared with other hydroxycinnamates, although UGT71C1 also exhibited substantial activity towards flavonoid substrates, known to have structural features that can be recognized by many different UGTs. The expression of UGT71C1 in transgenic Arabidopsis was driven by the constitutive cauliflower mosaic virus 35 S (CaMV35S) promoter. Nine independent transgenic lines were taken to homozygosity and characterized by Northern-blot analysis, assay of enzyme activity in leaf extracts and HPLC analysis of the glucosides. The level of expression of UGT71C1 was enhanced considerably in several lines, leading to a higher level of the corresponding enzyme activity and a higher level of caffeoyl-3-O-glucoside. The data are discussed in the context of the utility of UGTs for natural product biotransformations.


Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 4949
Author(s):  
Jonathan Hira ◽  
Md. Jalal Uddin ◽  
Marius M. Haugland ◽  
Christian S. Lentz

Chemical probes have been instrumental in microbiology since its birth as a discipline in the 19th century when chemical dyes were used to visualize structural features of bacterial cells for the first time. In this review article we will illustrate the evolving design of chemical probes in modern chemical biology and their diverse applications in bacterial imaging and phenotypic analysis. We will introduce and discuss a variety of different probe types including fluorogenic substrates and activity-based probes that visualize metabolic and specific enzyme activities, metabolic labeling strategies to visualize structural features of bacterial cells, antibiotic-based probes as well as fluorescent conjugates to probe biomolecular uptake pathways.


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