scholarly journals Metalloproteins in the Biology of Heterocysts

Life ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 32 ◽  
Author(s):  
Rafael Pernil ◽  
Enrico Schleiff
Keyword(s):  
N2 Fixation ◽  
Metabolic Networks ◽  
Current Knowledge ◽  
O2 Evolution ◽  
Electron Transport Chains ◽  
Comprehensive Picture ◽  
The One ◽  
Almost All ◽  
H2 Metabolism ◽  
Storage Energy

Cyanobacteria are photoautotrophic microorganisms present in almost all ecologically niches on Earth. They exist as single-cell or filamentous forms and the latter often contain specialized cells for N2 fixation known as heterocysts. Heterocysts arise from photosynthetic active vegetative cells by multiple morphological and physiological rearrangements including the absence of O2 evolution and CO2 fixation. The key function of this cell type is carried out by the metalloprotein complex known as nitrogenase. Additionally, many other important processes in heterocysts also depend on metalloproteins. This leads to a high metal demand exceeding the one of other bacteria in content and concentration during heterocyst development and in mature heterocysts. This review provides an overview on the current knowledge of the transition metals and metalloproteins required by heterocysts in heterocyst-forming cyanobacteria. It discusses the molecular, physiological, and physicochemical properties of metalloproteins involved in N2 fixation, H2 metabolism, electron transport chains, oxidative stress management, storage, energy metabolism, and metabolic networks in the diazotrophic filament. This provides a detailed and comprehensive picture on the heterocyst demands for Fe, Cu, Mo, Ni, Mn, V, and Zn as cofactors for metalloproteins and highlights the importance of such metalloproteins for the biology of cyanobacterial heterocysts.

scholarly journals THE USE OF SURVIVAL TECHNIQUES IN RESCUE PROCEEDINGS ON THE EXAMPLE OF THE USE OF MEDICINAL PLANTS

2020 ◽  
Vol 7 (3) ◽  
pp. 224-232
Author(s):  
Łukasz Kucharski
Keyword(s):  
Emergency Medicine ◽  
Medicinal Plants ◽  
Practical Knowledge ◽  
Current Knowledge ◽  
Extreme Conditions ◽  
Unified Framework ◽  
Part Time Students ◽  
The One ◽  
Difficult Terrain ◽  
Almost All

Introduction: The text is a response to the results of research conducted on medical rescuers and students of the field of emergency medicine, which unambiguously present a lack of knowledge on the one hand, and the need to acquire knowledge in the field of survival for rescue operations on the other. The work contains one of the survival techniques used in the field using the surrounding environment in the form of the use of plants that have antihemorrhagic properties. The aim: In this text, the main attention has been paid to aspects related to the use of survival techniques in rescue proceedings. At the same time, an attempt was made to present the use of medicinal plants in rescue operations both at the level of first aid and medical rescue operations in extreme conditions, as a complement to the multimodal approach to a trauma patient. Material and methods: The study was conducted at the turn of February and March 2020, which was attended by 52 part-time students in the field of emergency medicine at the University of Social Sciences in Lublin. Among the research techniques, a proprietary survey created for the purpose of verifying the topic of work was used, consisting of the record and questions determining the legitimacy of using survival techniques in rescue operations. Results: Almost all of the surveyed students believe that theoretical and practical knowledge in the field of survival would be useful in the profession of a paramedic, while the majority of respondents claim that first degree studies in the field of emergency medicine do not prepare a paramedic to work in crisis and extreme conditions. Conclusions: There is potential that gives us the natural environment in the form of plants that can be successfully used in rescue operations in difficult terrain. In addition, both students and paramedics show interest and training need in the use of survival techniques used in rescue operations. Therefore, one should strive to create a unified framework program for teaching future paramedics, based on current knowledge in the field of survival techniques used in emergency medical services already at the Higher Education level.

scholarly journals The Diagnosis and Therapy of Degenerative Knee Joint Disease: Expert Consensus from the Chinese Pain Medicine Panel

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Dong Huang ◽  
Yan-Qing Liu ◽  
Li-Shuang Liang ◽  
Xue-Wu Lin ◽  
Tao Song ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Diagnosis And Treatment ◽  
Joint Disease ◽  
Knee Joints ◽  
Reproduction Rate ◽  
Pain Specialist ◽  
Chinese Association ◽  
The One ◽  
Almost All ◽  
Based Medicine

At present, there are many constantly updated guidelines and consensuses on the diagnosis and treatment of osteoarthritis both at home and abroad. The recommendations established using methods of evidence-based medicine has experienced strict research on controlling bias and promoting reproduction rate. As a result, the previous evidence was reevaluated, and a lot of changes were provoked in the diagnosis and treatment concept of osteoarthritis. However, several methods not recommended by foreign guidelines are still in use in the current clinical practice in China. On the one hand, Chinese experts have not reached extensive consensus on whether it is necessary to make changes according to foreign guidelines. On the other hand, almost all the current relevant guidelines are on osteoarthritis, but the lesions around knee joints which, as a whole, bear the largest weight in human body, cannot be ignored. For this purpose, Chinese Association for the Study of Pain (CASP) organized some leading experts to formulate this Chinese Pain Specialist Consensus on the diagnosis and treatment of degenerative knee osteoarthritis (DKOA) in combination with the guidelines in foreign countries and the expert experience of clinical practice in China. The consensus, which includes the definition, pathophysiology, epidemiology, clinical manifestation, diagnostic criteria, and treatments of DKOA, is intended to be used by first-line doctors, including pain physicians to manage patients with DKOA.

scholarly journals The Cross-Talk between Mesenchymal Stem Cells and Immune Cells in Tissue Repair and Regeneration

2021 ◽  
Vol 22 (5) ◽  
pp. 2472
Author(s):  
Carl Randall Harrell ◽  
Valentin Djonov ◽  
Vladislav Volarevic
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Immune Cells ◽  
Tissue Repair ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Multipotent Stem Cells ◽  
Tissue Repair And Regeneration ◽  
Almost All ◽  
And Function

Mesenchymal stem cells (MSCs) are self-renewable, rapidly proliferating, multipotent stem cells which reside in almost all post-natal tissues. MSCs possess potent immunoregulatory properties and, in juxtacrine and paracrine manner, modulate phenotype and function of all immune cells that participate in tissue repair and regeneration. Additionally, MSCs produce various pro-angiogenic factors and promote neo-vascularization in healing tissues, contributing to their enhanced repair and regeneration. In this review article, we summarized current knowledge about molecular mechanisms that regulate the crosstalk between MSCs and immune cells in tissue repair and regeneration.

scholarly journals The Diverse Calpain Family in Trypanosomatidae: Functional Proteins Devoid of Proteolytic Activity?

Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 299
Author(s):  
Vítor Ennes-Vidal ◽  
Marta Helena Branquinha ◽  
André Luis Souza dos Santos ◽  
Claudia Masini d’Avila-Levy
Keyword(s):  
Proteolytic Activity ◽  
Current Knowledge ◽  
Current Therapy ◽  
Calcium Dependent ◽  
Administration Routes ◽  
Life Threatening ◽  
Living Organisms ◽  
Almost All ◽  
Open Question ◽  
Calpain Inhibitors

Calpains are calcium-dependent cysteine peptidases that were originally described in mammals and, thereafter, their homologues were identified in almost all known living organisms. The deregulated activity of these peptidases is associated with several pathologies and, consequently, huge efforts have been made to identify selective inhibitors. Trypanosomatids, responsible for life-threatening human diseases, possess a large and diverse family of calpain sequences in their genomes. Considering that the current therapy to treat trypanosomatid diseases is limited to a handful of drugs that suffer from unacceptable toxicity, tough administration routes, like parenteral, and increasing treatment failures, a repurposed approach with calpain inhibitors could be a shortcut to successful chemotherapy. However, there is a general lack of knowledge about calpain functions in these parasites and, currently, the proteolytic activity of these proteins is still an open question. Here, we highlight the current research and perspectives on trypanosomatid calpains, overview calpain description in these organisms, and explore the potential of targeting the calpain system as a therapeutic strategy. This review gathers the current knowledge about this fascinating family of peptidases as well as insights into the puzzle: are we unable to measure calpain activity in trypanosomatids, or are the functions of these proteins devoid of proteolytic activity in these parasites?

scholarly journals Application of Hyperspectral Imaging in the Assessment of Drought and Salt Stress in Magneto-Primed Triticale Seeds

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 835
Author(s):  
Jose Alvarez ◽  
Elvira Martinez ◽  
Belén Diezma
Keyword(s):  
Salt Stress ◽  
Hyperspectral Imaging ◽  
Human Observer ◽  
Negative Effects ◽  
Stress Symptoms ◽  
Data Variability ◽  
Drought And Salt Stress ◽  
The One ◽  
Almost All ◽  
Germination Parameters

Hyperspectral imaging is an appropriate method to thoroughly investigate the microscopic structure of internally heterogeneous agro-food products. By using hyperspectral technology, identifying stress symptoms associated with salinity, before a human observer, is possible, and has obvious benefits. The objective of this paper was to prove the suitability of this technique for the analysis of Triticale seeds subjected to both magneto-priming and drought and salt stress conditions, in terms of image differences obtained among treatments. It is known that, on the one hand, drought and salt stress treatments have negative effects on seeds of almost all species, and on the other hand, magneto-priming enhances seed germination parameters. Thus, this study aimed to relate hyperspectral imaging values—neither positive nor negative in themselves—to the effects mentioned above. Two main conclusions were reached: Firstly, the hyperspectral application is a feasible method for exploring the Triticale structure and for making distinctions under different drought and salt stress treatments, in line with the data variability obtained. Secondly, the lower spectral reflectance in some treatments—in the 400–1000 nm segment—is the result of a great number of chemical compounds in the seed that could be related to magneto-priming.

scholarly journals Hepatitis E Virus in Croatia in the “One-Health” Context

Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 699
Author(s):  
Anna Mrzljak ◽  
Lorena Jemersic ◽  
Vladimir Savic ◽  
Ivan Balen ◽  
Maja Ilic ◽  
...  
Keyword(s):  
Hepatitis E Virus ◽  
Current Knowledge ◽  
Hepatitis E ◽  
Human Case ◽  
Interspecies Transmission ◽  
Genotype 3 ◽  
Chronic Patients ◽  
Indirect Contact ◽  
The One ◽  
Foodborne Infection

Hepatitis E virus (HEV) is the most common cause of viral hepatitis globally. The first human case of autochthonous HEV infection in Croatia was reported in 2012, with the undefined zoonotic transmission of HEV genotype 3. This narrative review comprehensively addresses the current knowledge on the HEV epidemiology in humans and animals in Croatia. Published studies showed the presence of HEV antibodies in different population groups, such as chronic patients, healthcare professionals, voluntary blood donors and professionally exposed and pregnant women. The highest seroprevalence in humans was found in patients on hemodialysis in a study conducted in 2018 (27.9%). Apart from humans, different studies have confirmed the infection in pigs, wild boars and a mouse, indicating the interspecies transmission of HEV due to direct or indirect contact or as a foodborne infection. Continued periodical surveys in humans and animals are needed to identify the possible changes in the epidemiology of HEV infections.

scholarly journals Catalytic Diversity of GH30 Xylanases

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4528
Author(s):  
Katarína Šuchová ◽  
Vladimír Puchart ◽  
Nikolaj Spodsberg ◽  
Kristian B. R. Mørkeberg Krogh ◽  
Peter Biely
Keyword(s):  
Methyl Ester ◽  
Catalytic Properties ◽  
Specific Activity ◽  
Current Knowledge ◽  
Carboxyl Group ◽  
Weak Effect ◽  
Bacterial Enzymes ◽  
Catalytic Activities ◽  
Almost All ◽  
Free Carboxyl

Catalytic properties of GH30 xylanases belonging to subfamilies 7 and 8 were compared on glucuronoxylan, modified glucuronoxylans, arabinoxylan, rhodymenan, and xylotetraose. Most of the tested bacterial GH30-8 enzymes are specific glucuronoxylanases (EC 3.2.1.136) requiring for action the presence of free carboxyl group of MeGlcA side residues. These enzymes were not active on arabinoxylan, rhodymenan and xylotetraose, and conversion of MeGlcA to its methyl ester or its reduction to MeGlc led to a remarkable drop in their specific activity. However, some GH30-8 members are nonspecific xylanases effectively hydrolyzing all tested substrates. In terms of catalytic activities, the GH30-7 subfamily is much more diverse. In addition to specific glucuronoxylanases, the GH30-7 subfamily contains nonspecific endoxylanases and predominantly exo-acting enzymes. The activity of GH30-7 specific glucuronoxylanases also depend on the presence of the MeGlcA carboxyl, but not so strictly as in bacterial enzymes. The modification of the carboxyl group of glucuronoxylan had only weak effect on the action of predominantly exo-acting enzymes, as well as nonspecific xylanases. Rhodymenan and xylotetraose were the best substrates for exo-acting enzymes, while arabinoxylan represented hardly degradable substrate for almost all tested GH30-7 enzymes. The results expand current knowledge on the catalytic properties of this relatively novel group of xylanases.

scholarly journals Proteomic and Genomic Studies on Lizard Venoms in the Last Decade

2010 ◽  
Vol 3 ◽  
pp. PRI.S3693 ◽  
Author(s):  
Hang Fai Kwok ◽  
Craig Ivanyi ◽  
Andrew Morris ◽  
Chris Shaw
Keyword(s):  
Natural Resources ◽  
Potential Benefit ◽  
Current Knowledge ◽  
The State ◽  
Bioactive Molecules ◽  
Genomic Research ◽  
Active Compounds ◽  
Current Review ◽  
Comprehensive Picture ◽  
Genomic Studies

Traditionally man has looked to nature to provide cures for diseases. This approach still exists today in the form of ‘bio-prospecting’ for therapeutically-active compounds in venoms. For example, the venoms of many reptiles offer a spectacular laboratory of bioactive molecules, including peptides and proteins. In the last 10–15 years, there have been a number of major proteomic and genomic research breakthroughs on lizard venoms. In this current review, the key findings from these proteomic and genomic studies will be critically discussed and suggestions will be offered for future focused investigations. It is our intention that this article will not only provide a comprehensive picture of the state of current knowledge of the components of lizard venoms, but also engender awareness in readers of the need to protect and conserve such uniquely precious natural resources for several reasons, including the potential benefit of humankind.

scholarly journals Hypoxia and Hypoxia-Inducible Factor Signaling in Muscular Dystrophies: Cause and Consequences

2021 ◽  
Vol 22 (13) ◽  
pp. 7220
Author(s):  
Thuy-Hang Nguyen ◽  
Stephanie Conotte ◽  
Alexandra Belayew ◽  
Anne-Emilie Declèves ◽  
Alexandre Legrand ◽  
...  
Keyword(s):  
Cell Function ◽  
Current Knowledge ◽  
Genetic Defect ◽  
Hypoxia Inducible Factor ◽  
Muscular Dystrophies ◽  
Compensatory Mechanisms ◽  
Hypoxia Response ◽  
Muscle Disorders ◽  
Almost All ◽  
The Impact

Muscular dystrophies (MDs) are a group of inherited degenerative muscle disorders characterized by a progressive skeletal muscle wasting. Respiratory impairments and subsequent hypoxemia are encountered in a significant subgroup of patients in almost all MD forms. In response to hypoxic stress, compensatory mechanisms are activated especially through Hypoxia-Inducible Factor 1 α (HIF-1α). In healthy muscle, hypoxia and HIF-1α activation are known to affect oxidative stress balance and metabolism. Recent evidence has also highlighted HIF-1α as a regulator of myogenesis and satellite cell function. However, the impact of HIF-1α pathway modifications in MDs remains to be investigated. Multifactorial pathological mechanisms could lead to HIF-1α activation in patient skeletal muscles. In addition to the genetic defect per se, respiratory failure or blood vessel alterations could modify hypoxia response pathways. Here, we will discuss the current knowledge about the hypoxia response pathway alterations in MDs and address whether such changes could influence MD pathophysiology.

BACTERIAL MENINGITIS

PEDIATRICS ◽  
1973 ◽  
Vol 52 (4) ◽  
pp. 586-600
Author(s):  
David H. Smith ◽  
David L. Ingram ◽  
Arnold L. Smith ◽  
Floyd Gilles ◽  
M. J. Bresnan
Keyword(s):  
Bacterial Meningitis ◽  
Medical Care ◽  
Newborn Infant ◽  
Antibacterial Therapy ◽  
Tuberculous Meningitis ◽  
Current Knowledge ◽  
The Past ◽  
Meningococcal Group ◽  
Group A ◽  
Almost All

Prior to the introduction of specific antibacterial therapy, bacterial meningitis was a disease with a universally fatal or disastrous outcome. The introduction of typespecific antiserum, and then of the antibacterial drugs, improved this situation dramatically. Improvements in the general medical care of acutely ill children, and the introduction of a series of more potent antibiotics against its bacterial causes helped to generate an attitude that bacterial meningitis was, or soon would be, a disease of the past. The experience of the past two decades belies this thesis. Today, interest in many facets of this disease has been renewed by many physicians concerned with the health of children: the epidemiology, pathophysiology, diagnosis, and treatment. This symposium attempts to summarize for the practitioner the highlights of current knowledge in this area, and to outline certain areas in which recent advances can be anticipated, or will be studied. Tuberculous meningitis will be omitted for the sake of brevity, as will the special problems of meningitis in the newborn infant. There has been a resurgence of interest in developing vaccines to prevent Hemophilus influenzae b, pneumococcal, and meningococcal Group A, B, and C meningitis. These organisms cause almost all the bacterial meningitis after the first two months of life. If, as now seems possible, vaccines against most or all of these organisms will soon become available, those children having the greatest risk must be defined to determine who, and at what age should have priority in receiving the vaccine(s). A. THE CURRENT MAGNITUDE OF THE PROBLEM

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