A Two-Holed Story: Structural Secrets About ClC Proteins Become Unraveled?

Physiology ◽  
2004 ◽  
Vol 19 (5) ◽  
pp. 293-299 ◽  
Author(s):  
Elena Babini ◽  
Michael Pusch
Keyword(s):  
Functional Properties ◽  
Short Review ◽  
Biophysical Properties ◽  
Physiological Functions ◽  
X Ray ◽  
Almost All

ClC Cl− channels are found in almost all organisms, ranging from bacteria to mammals, in which nine Cl− channels belonging to the ClC family have been identified. The biophysical properties and physiological functions of ClC Cl− channels have been extensively reviewed. In this short review, we will focus on recent results obtained on the X-ray structure and functional properties of the prokaryotic ClC-ec1 protein and some results obtained on the role of the cytoplasmic COOH terminus of mammalian ClCs.

The Role of the Coelomic Fluid in the Movements of Earthworms

1950 ◽  
Vol 27 (1) ◽  
pp. 110-122 ◽  
Author(s):  
G. E. NEWELL
Keyword(s):  
Short Review ◽  
The Body ◽  
Coelomic Fluid ◽  
Average Pressure ◽  
Normal Range ◽  
Tail Region ◽  
X Ray ◽  
Effective Barrier ◽  
Intrinsic Muscles

1. A short review is given of the coelom and of its morphological relations in the earthworm. 2. The arrangement of the intrinsic muscles in a typical septum is described. Four main sets of muscles are recognized: viz. radial muscles, circular muscles, oblique muscles, and the sphincter around the ventral foramen. 3. It is suggested that the function of the radial, circular and possibly of the oblique muscles is to control bulging of the septa, and so serve to localize differences in pressure in the coelomic fluid. Normally, in active worms, the sphincter of the ventral foramen is contracted and forms an effective barrier to the passage of fluid from one coelomic compartment to the next. This was verified experimentally and by X-ray photography. 4. A series of measurements of the pressure in the coelomic fluid in different regions of active worms was recorded by means of a capillary manometer and by the use of a spoon-gauge apparatus. Manometric measurements showed the average pressure in the anterior third of the body to be 16.0 cm. water and in the tail region to be 8.0 cm. water. The corresponding figures obtained with a spoon gauge were 13.5 and 8.5 cm. water. The pressure in narcotized worms is zero. 5. These results are discussed, and it is pointed out that the manometer readings suffer from the disadvantage of failing to show the rapid fluctuations in pressure which occur during wriggling movements of the worms. 6. It is calculated from these pressure readings that a worm can exert a forward thrust equivalent to forces of between 1.5 and 8.0 g. These figures agree well with those obtained by Gray & Lissman by the use of a special torsion balance. 7. The burrowing movements of earthworms are briefly described. 8. It is shown that the sphincters of the dorsal pores and of the nephridiopores do not normally allow of the escape of coelomic fluid, and will withstand a pressure well outside the normal range.

scholarly journals Theoretical Implications of Diffuse Non-Thermal Emission from Clusters of Galaxies

2002 ◽  
Vol 199 ◽  
pp. 141-148
Author(s):  
T.A. Enßlin
Keyword(s):  
Thermal Emission ◽  
Extreme Ultraviolet ◽  
Short Review ◽  
Radio Galaxies ◽  
High Energy ◽  
Clusters Of Galaxies ◽  
Thermal Electron ◽  
Electron Population ◽  
X Ray

A short review on theoretical implications of non-thermal emission (radio, extreme ultraviolet, high energy X-ray) from the intra-cluster medium is given. The origin of cluster radio halos and cluster radio relics is discussed within the framework of a network of processes producing a non-thermal electron population. Emphasis is given to the role of old, remnant, presently invisible relativistic plasma released by former radio galaxies.

Impact Analysis of Machine Learning Techniques for COVID-19 Diagnosis: A Critical Review

2021 ◽  
Vol 12 (2) ◽  
pp. 510-516
Author(s):  
Anshul, Et. al.
Keyword(s):  
Machine Learning ◽  
Deep Learning ◽  
Severe Acute Respiratory Syndrome ◽  
Impact Analysis ◽  
Machine Learning Techniques ◽  
X Ray ◽  
Learning Techniques ◽  
The World ◽  
Almost All

COVID-19 virus belongs to the severe acute respiratory syndrome (SARS) family raised a situation of health emergency in almost all the countries of the world. Numerous machine learning and deep learning based techniques are used to diagnose COVID positive patients using different image modalities like CT SCAN, X-RAY, or CBX, etc. This paper provides the works done in COVID-19 diagnosis, the role of ML and DL based methods to solve this problem, and presents limitations with respect to COVID-19 diagnosis.

scholarly journals Role of Citicoline in the Management of Traumatic Brain Injury

2021 ◽  
Vol 14 (5) ◽  
pp. 410
Author(s):  
Julio J. Secades
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Head Injury ◽  
Brain Ischemia ◽  
Potential Role ◽  
Short Review ◽  
Excellent Safety Profile ◽  
Almost All ◽  
Recovery Of Consciousness

Head injury is among the most devastating types of injury, specifically called Traumatic Brain Injury (TBI). There is a need to diminish the morbidity related with TBI and to improve the outcome of patients suffering TBI. Among the improvements in the treatment of TBI, neuroprotection is one of the upcoming improvements. Citicoline has been used in the management of brain ischemia related disorders, such as TBI. Citicoline has biochemical, pharmacological, and pharmacokinetic characteristics that make it a potentially useful neuroprotective drug for the management of TBI. A short review of these characteristics is included in this paper. Moreover, a narrative review of almost all the published or communicated studies performed with this drug in the management of patients with head injury is included. Based on the results obtained in these clinical studies, it is possible to conclude that citicoline is able to accelerate the recovery of consciousness and to improve the outcome of this kind of patient, with an excellent safety profile. Thus, citicoline could have a potential role in the management of TBI.

scholarly journals Role of Citicoline in the Management of Traumatic Brain Injury

2021 ◽  
Author(s):  
Julio J Secades
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Head Injury ◽  
Brain Ischemia ◽  
Potential Role ◽  
Short Review ◽  
Excellent Safety Profile ◽  
Almost All ◽  
Recovery Of Consciousness

Head injury is among the most devastating types of injury, specifically called Traumatic Brain Injury (TBI). There is need to diminish the morbidity related with TBI and to improve the outcome of patients suffering TBI. Among the improvements on the treatment of TBI, neuroprotection is one of the upcoming improvements. Citicoline has been used in the management of brain ischemia related disorders, such as TBI. Citicoline has biochemical, pharmacological, and pharmacokinetic characteristics that make it a potentially useful neuroprotective drug for the management of TBI. A short review of these characteristics is included in this paper. Also, a narrative review of almost all the published or communicated studies performed with this drug in the management of patients with head injury is included. Based on the results obtained in these clinical studies, it is possible to conclude that citicoline was able to accelerate recovery of consciousness and to improve the outcome of this kind of patients, with an excellent safety profile. Thus, citicoline could have a potential role in the management of TBI.

scholarly journals Observational Study to evaluate the role of Ultrasonography and X-Ray in Urinary Disease

2020 ◽  
Vol 11 (1) ◽  
pp. 1206-1209
Author(s):  
Amit Kumar Singh ◽  
Mishra S.S. ◽  
Arun Kumar Dwivedi
Keyword(s):  
Urine Analysis ◽  
Histopathological Examination ◽  
Radiological Examination ◽  
Urinary System ◽  
X Ray ◽  
Physical Problems ◽  
Wide Range ◽  
Contrast Ultrasonography ◽  
Almost All

Urinary diseases are very common in our society which system constitutes kidneys ureters urinary bladder and urethra various abnormalities occur in these organs due to many reasons like infection inflammation metabolic abnormalities neoplastic changes trauma etc. these abnormalities lead to various physical problems ending into death many times the abnormalities of urinary system can be diagnosed by hematological examination urine analysis radiological examination and histopathological examination especially radiological examination provide wide range of diagnosis of disease of urinary system of almost all origin although various radiological technique like X-ray (plain and contrast) Ultrasonography CT scan MRI and many others are available but in present study X-ray (plain and contrast ) and ultrasonography were used for diagnosis of disease of urinary system because of its easy availability and affordability the diseases of urinary system has been described under the name of Mutrakrichha and Mutraghata  in ayurveda these two conditions are in fact group of clinical entities in which urination is difficult and retention is present respectively further they are divided into various subtypes these conditions resembles clinically with various types of urinary diseases early diagnosis has been the always advocated by ayurveda by virtue of this prevention and management becomes easy in the present study written informed consent has been taken from all the patients early detection of these conditions facilitates the management otherwise renal failure may complicate the condition

scholarly journals Matrix metalloproteinases (MMP-1, -8, -13) in chronic periapical lesions

2008 ◽  
Vol 65 (12) ◽  
pp. 882-886 ◽  
Author(s):  
Biljana Andonovska ◽  
Cena Dimova ◽  
Saso Panov
Keyword(s):  
Matrix Metalloproteinases ◽  
Proteolytic Enzymes ◽  
High Concentration ◽  
Collagenase Activity ◽  
X Ray ◽  
Periapical Lesions ◽  
Membrane Components ◽  
Almost All ◽  
Basement Membrane Components

Background/Aim. Matrix metalloproteinases (MMPs) are proteolytic enzymes capable of degrading almost all extracellular matrix and basement membrane components in many destructive pathological processes, such as chronic inflammation and bone-destructive lesions. The aim of this study was to determinate the correlation between concentration of collagenases (MMP-1, -8, -13) in chronic periapical lesions and their dimension calculated with software predilection through X-ray. Metods. Chronic periapical tissues were collected by periapical surgery from 60 teeth with clinically and radiographically verified different chronic periapical lesions (20 granulomas, 20 diffuse periapical lesions, 10 cysts). Ten normal pulps used as controls were obtained by extirpation of the pulp of impacted third molars after their surgery. For rapid analysis of MMP-1, -8, -13 collagenase activities in the examined material Chemicon Collagenase Activity Assay Kit were used. From the X-ray trough software predilection (Image Tool3 Program) of the volume of chronic periapical tissue, correlation between concentration of MMPs in the periapical lesions and their dimension was confirmed. Results. Different concentrations of collagenases (MMP-1, -8 and -13) in chronic periapical process from different inflammation types showed different activity of MMPs. The obtained results showed the highest values of collagenases concentration (MMP-1, -8, -13) in chronic diffuse lesions (5.39 ng/ml). Low values of concentration of MMPs accompanied less serious lesions, whereas chronical periapical lesions of large dimension had high concentration of MMPs, which was proportional to progression of the lesion and destruction of bone tissue. Conclusions. This study confirmed the destructive role of collagenases (MMP-1, -8 and -13) in inflammation process, which directly depends on the concentration of MMPs in pathologically changed tissue.

Quaternary structure of Limulus polyphemus hemocyanin

1978 ◽  
Vol 36 (2) ◽  
pp. 176-177
Author(s):  
T. Wichertjes ◽  
E.J. Kwak ◽  
E.F.J. Van Bruggen
Keyword(s):  
Electron Microscopy ◽  
Functional Properties ◽  
Horseshoe Crab ◽  
Temperature Jump ◽  
Quaternary Structure ◽  
Crystallographic Analysis ◽  
Limulus Polyphemus ◽  
Oxygen Binding ◽  
X Ray ◽  
Intact Molecule

Hemocyanin of the horseshoe crab (Limulus polyphemus) has been studied in nany ways. Recently the structure, dissociation and reassembly was studied using electron microscopy of negatively stained specimens as the method of investigation. Crystallization of the protein proved to be possible and X-ray crystallographic analysis was started. Also fluorescence properties of the hemocyanin after dialysis against Tris-glycine buffer + 0.01 M EDTA pH 8.9 (so called “stripped” hemocyanin) and its fractions II and V were studied, as well as functional properties of the fractions by NMR. Finally the temperature-jump method was used for assaying the oxygen binding of the dissociating molecule and of preparations of isolated subunits. Nevertheless very little is known about the structure of the intact molecule. Schutter et al. suggested that the molecule possibly consists of two halves, combined in a staggered way, the halves themselves consisting of four subunits arranged in a square.

Digital x-ray mapping of nanometer-size supported bimetallic catalysts

1988 ◽  
Vol 46 ◽  
pp. 530-531
Author(s):  
L. T. Germinario
Keyword(s):  
Background Radiation ◽  
Metal Cluster ◽  
Single Element ◽  
Beam Diameter ◽  
X Rays ◽  
X Ray ◽  
Major Interest ◽  
Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

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