scholarly journals Peptidase activities in Crotalus durissus terrificus semen

Reproduction ◽  
2008 ◽  
Vol 136 (6) ◽  
pp. 767-776 ◽  
Author(s):  
Camila Eduardo Marinho ◽  
Selma Maria Almeida-Santos ◽  
Sylvia Mendes Carneiro ◽  
Simone Cristina Yamasaki ◽  
Paulo Flavio Silveira
Keyword(s):  
Angiotensin Ii ◽  
Seminal Plasma ◽  
The Other ◽  
Type I ◽  
Activity Levels ◽  
Crotalus Durissus Terrificus ◽  
Membrane Bound ◽  
Crotalus Durissus ◽  
First Time

AbstractTo understand the role of peptidases in seminal physiology ofCrotalus durissus terrificus, activity levels of representative enzymes in semen and their sensitivities to inhibitors, cofactors, and peptide hormones were evaluated. The existence of seminal fractions and the association of peptidases with these fractions were also characterized for the first time in snakes. The prominent inhibitors of aminopeptidases (APs) were amastatin for acid, basic, and neutral; bestatin for basic; and diprotin A for dipeptidyl-IV. Cystyl and prolyl-imino APs were similarly susceptible to the majority of these inhibitors. The basic and neutral were characterized as metallo-peptidases, acid AP was activated by MnCl2, and cystyl, prolyl-imino, and type I pyroglutamyl were characterized as sulphydryl-dependent APs. Angiotensin II, vasotocin, bradykinin, fertilization-promoting peptide, and TRH altered the majority of these peptidase activities; these peptides are possible substrates and/or modulators of these peptidases. Peptidase activities were found in all seminal fractions: seminal plasma (SP), prostasome-like (PR) structures, and soluble (S-) and membrane-bound fractions (MFs) of spermatozoa. The levels of activity of each peptidase varied among different seminal fractions. In SP, the higher activities were puromycin-insensitive neutral and basic APs. In PR, the higher activity was puromycin-insensitive neutral AP. In spermatozoa, the higher activity in subcellular SF was puromycin-sensitive neutral, while in MF both puromycin-sensitive and -insensitive neutral APs were equally higher than the other examined peptidases. Data suggested that these peptidases, mainly basic and neutral, have a high relevance in regulating seminal functions ofC. d. terrificus.

The Activities of the Tube Feet of Asterias Rubens L

1947 ◽  
Vol s3-88 (1) ◽  
pp. 1-14
Author(s):  
J. E. SMITH
Keyword(s):  
Forward Direction ◽  
The Other ◽  
Asterias Rubens ◽  
Ideal Form ◽  
First Time ◽  
Intrinsic Musculature ◽  
Tube Feet ◽  
Postural Muscles ◽  
The Ideal

1. An account is given of the muscular anatomy of the foot and ampulla of Asterias rubens. An intrinsic musculature of the sucker figured by Cuénot (1891) and Chadwick (1923) is shown not to be present; on the other hand, postural muscles responsible for orientating the podium, levator fibres which ‘cup’ the sucker, and radial fibres which flatten it are described and figured for the first time. 2. The role of the different muscle systems, the collagen connective tissue, and the fluid of the hydrocoel in protracting and retracting the foot, and in effecting the attachment and detachment of the sucker, is discussed. 3. Evidence is presented, to show that postural pointing of the foot is brought about by the contraction of a ring of muscles encircling the base of the podium. The orienting muscles are functionally, but not anatomically, distinct from the longitudinal fibres of the retractor sheath. 4. The ambulatory step is shown to comprise a series of linked phases of static posture and of movement. Each phase is characterized by the contraction of one member of each of the two opposing pairs of muscles engaged in the development of the step. The two pairs of muscles are (1) the anterior and posterior orienting fibres, and (2) the protractors and retractors of the foot. In its ideal form the step comprises four phases of static posture alternating with four movements. Each movement is ushered in by a reversal of the contraction-relaxation relationships of one of the two pairs of opposing muscle systems. Four such changes are possible and they occur in a sequence that ensures the orderly succession of the four movements of protraction, swing back, retraction, and swing forward, of which movements the idealized stepping cycle is composed. 5. The actual locomotory step departs from the ideal form in two respects: (1) it is liable to become disrupted by a delay in the initiation of the protraction or of the backswing movement, and (2) withdrawal of the podium occurs simultaneously with its re-orientation in the forward direction. It is pointed out that these variations are explicable on the assumption that, in the two series of opposing muscle pairs, the retractor fibres are more readily excited to contract than are their antagonists, and the anterior postural muscles than the posterior postural fibres.

Comments on the updated recommendations of the American College of Rheumatology (ACR) for the treatment of gout. Lifestyle (part 2)

2021 ◽  
Vol 15 (2) ◽  
pp. 83-88
Author(s):  
M. S. Eliseev
Keyword(s):  
Body Weight ◽  
Food Habits ◽  
The Other ◽  
Obese Patients ◽  
American College Of Rheumatology ◽  
The Russian Federation ◽  
The One ◽  
Effective Drugs ◽  
First Time

Updated ACR recommendations for the treatment of gout concerning lifestyle are discussed. Factors related to a lifestyle, above all food habits, for many years were of leading importance in the treatment of patients with gout, even after application of effective drugs. The authors of the updated ACR recommendations for the first time offered to reconsider the role of environmental factors in the genesis of gout and objectively assess the possibility of its non-drug treatment. On the one hand, regardless of the activity of the disease, the need for restrictions of the alcohol, purine-rich products and fructose-containing beverages, as well as the decrease of body weight in obese patients and vitamin C usage unviability are confirmed. On the other hand, these recommendations are conditional. Their new version of ACR recommendations is significantly different from both its previous version and other international and national recommendations, including recommendations on the diagnosis and treatment of gout used in the Russian Federation.

scholarly journals The Figure of Distrust: Prince A.S. Menshikov in the Maritime Department during the Period of Reforms, 1826–1828

2020 ◽  
Vol 4 (3) ◽  
pp. 702-733
Author(s):  
Kseniya V. Donik
Keyword(s):  
Methodological Approach ◽  
The Other ◽  
General Situation ◽  
Functional Characteristics ◽  
Problem Context ◽  
Agent Based ◽  
The One ◽  
First Time ◽  
Official Records

The article considers the role of Prince A. Menshikov as a specific type of agent of supreme authority in the process of reforming the maritime administration. The problem context of reforms resulted from the involvement of the naval generals and officials in abuses, which was a consequence of nepotism and unrest in the navy. The involvement of sailors in the Decembrist revolt significantly affected the attitude of the tsar to the general situation in the naval environment. Distrustful of the existing naval administration, Nicholas I needed an intermediary who would implement his idea of the arrangement of the navy on the one hand, and provide him with an objective “impartial” account of maritime problems, on the other hand. As a result of that, Adjutant General Prince A. Menshikov, who had had nothing to do with the naval service earlier, joined the navy to become the monarch’s agent in charge of the naval issues in the bodies of autocratic authority. The objective of the article is to identify the functions of such an agent based on the example of the Maritime Department. The sources of the article include official records and personal documents, some of which are introduced into scientific circulation for the first time. The principal methodological approach to the problem under study is an attempt to bring the appointment of Menshikov beyond the scope of narrow departmental history which was based on the unmotivated decision of the emperor and to propose an interpretation of the events in the context of tsarist government via agents, which has already been described in historiography. The author makes a conclusion about the interconnection between the crisis in the naval department, the attitude of the supreme authority towards it, and the appearance of the monarch’s agent with a number of his own functional characteristics.

scholarly journals Degradation of a Short-lived Glycoprotein from the Lumen of the Endoplasmic Reticulum: The Role of N-linked Glycans and the Unfolded Protein Response

1999 ◽  
Vol 10 (12) ◽  
pp. 4059-4073 ◽  
Author(s):  
Maddalena de Virgilio ◽  
Claudia Kitzmüller ◽  
Eva Schwaiger ◽  
Michael Klein ◽  
Gert Kreibich ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Unfolded Protein Response ◽  
The Other ◽  
Slow Phase ◽  
Type I ◽  
Unfolded Protein ◽  
Other Hand ◽  
The Unfolded Protein Response ◽  
Protein Response

We are studying endoplasmic reticulum–associated degradation (ERAD) with the use of a truncated variant of the type I ER transmembrane glycoprotein ribophorin I (RI). The mutant protein, RI332, containing only the N-terminal 332 amino acids of the luminal domain of RI, has been shown to interact with calnexin and to be a substrate for the ubiquitin-proteasome pathway. When RI332 was expressed in HeLa cells, it was degraded with biphasic kinetics; an initial, slow phase of ∼45 min was followed by a second phase of threefold accelerated degradation. On the other hand, the kinetics of degradation of a form of RI332 in which the single used N-glycosylation consensus site had been removed (RI332-Thr) was monophasic and rapid, implying a role of the N-linked glycan in the first proteolytic phase. RI332degradation was enhanced when the binding of glycoproteins to calnexin was prevented. Moreover, the truncated glycoprotein interacted with calnexin preferentially during the first proteolytic phase, which strongly suggests that binding of RI332 to the lectin-like protein may result in the slow, initial phase of degradation. Additionally, mannose trimming appears to be required for efficient proteolysis of RI332. After treatment of cells with the inhibitor of N-glycosylation, tunicamycin, destruction of the truncated RI variants was severely inhibited; likewise, in cells preincubated with the calcium ionophore A23187, both RI332 and RI332-Thr were stabilized, despite the presence or absence of the N-linked glycan. On the other hand, both drugs are known to trigger the unfolded protein response (UPR), resulting in the induction of BiP and other ER-resident proteins. Indeed, only in drug-treated cells could an interaction between BiP and RI332 and RI332-Thr be detected. Induction of BiP was also evident after overexpression of murine Ire1, an ER transmembrane kinase known to play a central role in the UPR pathway; at the same time, stabilization of RI332 was observed. Together, these results suggest that binding of the substrate proteins to UPR-induced chaperones affects their half lives.

scholarly journals Inducible microRNA-590-5p inhibits host antiviral response by targeting the soluble interleukin-6 (IL6) receptor

2018 ◽  
Vol 293 (47) ◽  
pp. 18168-18179 ◽  
Author(s):  
Yaqin Zhou ◽  
Zhangchuan Xia ◽  
Zhikui Cheng ◽  
Gang Xu ◽  
Xiaodan Yang ◽  
...  
Keyword(s):  
Viral Infection ◽  
Interleukin 6 ◽  
Underlying Mechanism ◽  
Antiviral Response ◽  
Type I ◽  
Interleukin 6 Receptor ◽  
Important Regulator ◽  
Membrane Bound ◽  
Host Antiviral Response

MicroRNA (miR)-590-5p has been identified as an important regulator of some signaling pathways such as cell proliferation and tumorigenesis. However, little is known about its role during viral infection. Here, we report that miR-590-5p was significantly induced by various viruses and effectively potentiated virus replication in different viral infection systems. Furthermore, miR-590-5p substantially attenuated the virus-induced expression of type I and type III interferons (IFNs) and inflammatory cytokines, resulting in impaired downstream antiviral signaling. Interleukin-6 receptor (IL6R) was identified as a target of miR-590-5p. Interestingly, the role of miR-590-5p in virus-triggered signaling was abolished in IL6R knockout cells, and this could be rescued by restoring the expression of the soluble IL6R (sIL6R) but not the membrane-bound IL6R (mIL6R), suggesting that sIL6R is indispensable for miR-590-5p in modulating the host antiviral response. Furthermore, miR-590-5p down-regulated endogenous sIL6R and mIL6R expression through a translational repression mechanism. These findings thus uncover a previously uncharacterized role and the underlying mechanism of miR-590-5p in the innate immune response to viral infection.

scholarly journals Role of IgM and angiotensin II Type I receptor autoantibodies in local complement activation in placental ischemia-induced hypertension in the rat

2016 ◽  
Vol 78 ◽  
pp. 38-47 ◽  
Author(s):  
Jean F. Regal ◽  
Megan E. Strehlke ◽  
Jenna M. Peterson ◽  
Cameron R. Wing ◽  
Jordan E. Parker ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Complement Activation ◽  
Type I ◽  
Induced Hypertension ◽  
Placental Ischemia

Role of the renin-angiotensin system in the pathogenesis of preeclampsia

2005 ◽  
Vol 288 (4) ◽  
pp. F614-F625 ◽  
Author(s):  
Dinesh M. Shah
Keyword(s):  
Angiotensin Ii ◽  
Renin Angiotensin System ◽  
Receptor Activation ◽  
Gravid Uterus ◽  
Type I ◽  
Hypertensive Disorder ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Organ Systems

Preeclampsia is a hypertensive disorder unique to pregnancy with consistent involvement of the kidney. The renin-angiotensin system (RAS) has been implicated in the pathogenesis of preeclampsia. In the gravid state, in addition to the RAS in the kidney, there is a tissue-based RAS in the uteroplacental unit. Increased renin expression observed both in human preeclampsia and in a transgenic mouse model with a human preeclampsia-like syndrome supports the concept that activation of the uteroplacental RAS, with angiotensin II entering the systemic circulation, may mediate the pathogenesis of preeclampsia. A novel disease paradigm of the two-kidney one-clip (2K-1C) Goldblatt model is presented for preeclampsia, wherein the gravid uterus is the clipped “kidney” and the two maternal kidneys represent the unclipped kidney. Validation of the 2K-1C Goldblatt model analogy requires evidence of elevated angiotensin II in the peripheral circulation before vascular maladaptation in preeclampsia. Convincing evidence of the elevation of angiotensin II in preeclampsia does not exist despite the fact that much of vascular pathogenesis appears to be due to angiotensin type I (AT1) receptor activation. Vascular maladaptation with increased vasomotor tone, endothelial dysfunction, and increased sensitivity to angiotensin II and norepinephrine in manifest preeclampsia may be explained on the basis of angiotensin II-mediated mechanisms. Recently, novel angiotensin II-related biomolecular mechanisms have been described in preeclampsia. These include AT1and bradykinin B2receptor heterodimerization and the production of an autoantibody against AT1. Various organ systems with a predilection for involvement in preeclampsia are each a site of a tissue-based RAS. How angiotensin II-mediated mechanisms may explain the primary clinical-pathological features of preeclampsia is described. Future investigations are proposed to more precisely define the role of activation of the uteroplacental RAS in the mechanisms underlying preeclampsia.

Immunosuppresive role of principal toxin (crotoxin) of Crotalus durissus terrificus venom

Toxicon ◽  
2004 ◽  
Vol 44 (6) ◽  
pp. 609-616 ◽  
Author(s):  
A. Rangel-Santos ◽  
C. Lima ◽  
M. Lopes-Ferreira ◽  
D.F. Cardoso
Keyword(s):  
Crotalus Durissus Terrificus ◽  
Role Of Principal ◽  
Crotalus Durissus

scholarly journals Late Paleogene herpetofaunas from the crossroads between two continents – new amphibian and reptile remains from the Oligocene of southern Balkans and Anatolia

2021 ◽  
Author(s):  
Georgios L. GEORGALIS ◽  
Andrej ČERŇANSKÝ ◽  
undefined Serdar MAYDA
Keyword(s):  
Eastern Europe ◽  
Central Europe ◽  
The Other ◽  
Southeastern Europe ◽  
Dispersal Route ◽  
First Time ◽  
Southern Balkans

We describe here new amphibian and reptile remains from three Oligocene localities of Turkey. Two of the localities (Kavakdere and Kocayarma) are situated in southeastern Europe and the other one (Kargi 2) in Anatolia, both areas where Oligocene herpetofauna is practically almost unknown. The material consists of albanerpetontids, pelobatid anurans, turtles, crocodylians, lacertids, scinciformatans, anguines, and “tropidophiids”. Albanerpetontids are for the first time identified in southeastern Europe, with the material being reminiscent of the younger species Albanerpeton inexpectatum Estes & Hoffstetter, 1976; the material potentially represents the oldest record of that species. Pelobatids, scinciformatans, and “tropidophiids” represent the oldest occurrences of these clades in the northeastern Mediterranean. The anguine genus Ophisaurus Daudin, 1803 is identified for the first time in the Paleogene of Eastern Europe. The “tropidophiids” are referred to two genera, Falseryx Szyndlar & Rage, 2003 and tentatively also to Platyspondylia Rage, 1974, with the latter having been so far exclusively known from western and central Europe. The role of a potential southern dispersal route of taxa among Asia and Europe, involving the area of southern Balkans and Anatolia, similarly to what has been recently demonstrated for mammals, is highlighted also for amphibians and reptiles.

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