Cl- regulates cryoglobulin structure: a new hypothesis for the physiopathological mechanism of temperature non-dependent cryoprecipitation

2004 ◽  
Vol 42 (6) ◽  
Author(s):  
Enrico Di Stasio ◽  
Patrizia Bizzarri ◽  
Milvia Casato ◽  
Antonio Galtieri ◽  
Massimo Fiorilli ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Clinical Signs ◽  
Cold Temperature ◽  
Pathogenetic Mechanism ◽  
Temperature Dependent ◽  
Temperature Changes ◽  
Significant Temperature ◽  
Neoplastic Disorders ◽  
New Hypothesis

AbstractCryoglobulins are pathological cold-precipitable immunoglobulins associated with a number of infectious, autoimmune and neoplastic disorders. Patients, when exposed to low temperatures, show symptoms related to intravascular precipitation of such immunoglobulins. The formation of cryoaggregates induced by exposure to cold temperature is the key pathogenetic mechanism. The subsequent intravascular precipitation can account for some clinical signs of peripheral vasculitis, but fails to explain the precipitation of cryoglobulins in regions where no significant temperature changes take place. We studied, in vitro, the activity of different ions on temperature-dependent aggregation of cryoglobulins and found that the concentration of Cl

scholarly journals A temperature-dependent translational switch controls biofilm development in Vibrio cholerae

2020 ◽  
Author(s):  
Teresa del Peso Santos ◽  
Jonathon Blake ◽  
Brandon Sit ◽  
Alyson R. Warr ◽  
Vladimir Benes ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Translational Control ◽  
Low Temperatures ◽  
Biofilm Formation ◽  
Common Mechanism ◽  
Seasonal Temperature ◽  
Temperature Dependent ◽  
Regulatory Cascade ◽  
Biofilm Development

AbstractThe gastrointestinal pathogen Vibrio cholerae frequently forms biofilms during its life cycle. Biofilm formation is vital for protection against environmental stresses and is thought to facilitate intestinal colonization. Adaptation to temperature is crucial for V. cholerae survival, as the pathogen is exposed to seasonal temperature variations in the aquatic environment, and temperature fluctuations during host-environment transitions. Here, we show that V. cholerae strains naturally lacking the master biofilm transcriptional regulator HapR are unable to develop colony rugosity at low temperatures. We find that BipA, a ribosome-associated GTPase, accounts for this temperature-dependent control of biofilm formation by repressing translation of the primary biofilm transcriptional activators VpsR and VpsT at low temperatures. In vitro studies demonstrate that low temperatures influence BipA structural conformation and decrease its sensitivity to proteolysis. Proteomic analyses reveal that BipA exerts temperature-dependent control over >200 proteins in V. cholerae involved in a multitude of cell processes, including biofilm assembly. Our study reveals a remarkable new facet of the complex V. cholerae biofilm regulatory cascade and suggests that combined transcriptional-translational control could be a common mechanism by which bacteria adapt to environmental flux.

scholarly journals Using a Digital Twin of an Electrical Stimulation Device to Monitor and Control the Electrical Stimulation of Cells in vitro

2021 ◽  
Vol 9 ◽  
Author(s):  
Julius Zimmermann ◽  
Kai Budde ◽  
Nils Arbeiter ◽  
Francia Molina ◽  
Alexander Storch ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Cellular Mechanisms ◽  
Temperature Changes ◽  
Digital Twin ◽  
Stimulation Parameters ◽  
Significant Temperature ◽  
And Control ◽  
Stimulation Of

Electrical stimulation for application in tissue engineering and regenerative medicine has received increasing attention in recent years. A variety of stimulation methods, waveforms and amplitudes have been studied. However, a clear choice of optimal stimulation parameters is still not available and is complicated by ambiguous reporting standards. In order to understand underlying cellular mechanisms affected by the electrical stimulation, the knowledge of the actual prevailing field strength or current density is required. Here, we present a comprehensive digital representation, a digital twin, of a basic electrical stimulation device for the electrical stimulation of cells in vitro. The effect of electrochemical processes at the electrode surface was experimentally characterised and integrated into a numerical model of the electrical stimulation. Uncertainty quantification techniques were used to identify the influence of model uncertainties on relevant observables. Different stimulation protocols were compared and it was assessed if the information contained in the monitored stimulation pulses could be related to the stimulation model. We found that our approach permits to model and simulate the recorded rectangular waveforms such that local electric field strengths become accessible. Moreover, we could predict stimulation voltages and currents reliably. This enabled us to define a controlled stimulation setting and to identify significant temperature changes of the cell culture in the monitored voltage data. Eventually, we give an outlook on how the presented methods can be applied in more complex situations such as the stimulation of hydrogels or tissue in vivo.

scholarly journals Determination of the heating pile numerical model parameters based on the laboratory strength tests of clay at low temperatures

2018 ◽  
Vol 50 (2) ◽  
pp. 159-169
Author(s):  
Bartosz Piotrowicz ◽  
Małgorzata Jastrzębska ◽  
Marian Łupieżowiec
Keyword(s):  
Low Temperatures ◽  
Laboratory Tests ◽  
Load Capacity ◽  
Model Parameters ◽  
Mechanical Parameters ◽  
Temperature Changes ◽  
Negative Effect ◽  
Significant Temperature ◽  
Freezing Liquid

Abstract Heating piles combine the function of the foundation and the heat source. They acquire heat from the ground through in built the installation. Inside the installation is non-freezing liquid at low temperature. In connection with the above, piles and the surrounding soil are exposed to significant temperature changes. As a result of these changes, the mechanical parameters of the soil and the behavior of the pile and soil contact surface were changed. This affects directly the load capacity of the heating piles. To describe this effect, laboratory tests were carried out to determine the thermal and mechanical parameters of the soil at low temperatures. The results from laboratory tests were applied as material parameters in the Z_Soil program. Based on the analysis using the finite element method, it was found that there is an negative effect on the friction on the surface of pile associated with the heat transfer between the soil and the pile.

In Vitro Effects of Urokinase — Prevention by Different Inhibitors

1990 ◽  
Vol 64 (03) ◽  
pp. 402-406 ◽  
Author(s):  
M D Oethinger ◽  
E Seifried
Keyword(s):  
In Vitro Study ◽  
Thrombin Time ◽  
Plasma Samples ◽  
Temperature Dependent ◽  
Chloromethyl Ketone ◽  
Control Value ◽  
Dose Time ◽  
In Vitro Effects ◽  
Full Protection

SummaryThe present in vitro study investigated dose-, time- and temperature-dependent effects of two-chain urokinase plasminogen activato(u-PA, urokinase) on normal citrated plasma. When 10 μg/ml u-PA wereadded to pooled normal plasma and incubated for 30 min at an ambient temperature (25° C), α2-antiplas-min decreased to 8% of the control value. Incubation on ice yielded a decrease to 45% of control,whereas α2-antiplasmin was fully consumed at 37° C. Fibrinogen and plasminogen fell to 46% and 39%, respectively, after a 30 min incubation at 25° C. Thrombin time prolonged to 190% of control.Various inhibitors were studied with respect to their suitability and efficacy to prevent these in vitro effects. Aprotinin exhibited a good protective effect on fibrinogen at concentrations exceeding 500 KlU/ml plasma. Its use, however, was limited due to interferences with some haemostatic assays. We could demonstrate that L-Glutamyl-L-Glycyl-L-Arginyl chloromethyl ketone (GGACK) and a specific polyclonal anti-u-PA-antibody (anti-u-PA-IgG) effectively inhibited urokinase-induced plasmin generation without interfering with haemostatic assays. The anti-u-PA-antibody afforded full protection ofα2-antiplasmin at therapeutic levels of u-PA.It is concluded that u-PA in plasma samples from patients during thrombolytic therapy may induce in vitro effects which should be prevented by the use of a suitable inhibitor such as GGACK or specific anti-u-PA-antibody.

Low Temperature Fault Isolation Using Soft Defect Localization

2012 ◽  
Author(s):  
Kristopher D. Staller
Keyword(s):  
Low Temperatures ◽  
Laser Scanning ◽  
Low Cost ◽  
Fault Isolation ◽  
Laser Scanning Microscopy ◽  
Cold Temperature ◽  
Multiple Point ◽  
Defect Localization ◽  
Low Levels

Abstract Cold temperature failures are often difficult to resolve, especially those at extreme low levels (< -40°C). Momentary application of chill spray can confirm the failure mode, but is impractical during photoemission microscopy (PEM), laser scanning microscopy (LSM), and multiple point microprobing. This paper will examine relatively low-cost cold temperature systems that can hold samples at steady state extreme low temperatures and describe a case study where a cold temperature stage was combined with LSM soft defect localization (SDL) to rapidly identify the cause of a complex cold temperature failure mechanism.

Magnetic nanostructured lipid carrier for dual triggered curcumin delivery: Preparation, characterization and toxicity evaluation on isolated rat liver mitochondria

2021 ◽  
pp. 088532822110346
Author(s):  
Mohammad Yoozbashi ◽  
Hamid Rashidzadeh ◽  
Mehraneh Kermanian ◽  
Somayeh Sadighian ◽  
Mir-Jamal Hosseini ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Liver Mitochondria ◽  
Rat Liver Mitochondria ◽  
Nanostructured Lipid Carrier ◽  
Mitochondrial Toxicity ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
Reducing Ability ◽  
Transmission Electron

In this research, magnetic nanostructured lipid carriers (Mag-NLCs) were synthesized for curcumin (CUR) delivery. NLCs are drug-delivery systems prepared by mixing solid and liquid (oil) lipids. For preparation of NLCs, cetylpalmitate was selected as solid lipid and fish oil as liquid lipid. CUR-Mag-NLCs were prepared using high-pressure homogenization technique and were characterized by methods including X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), and dynamic light scattering (DLS). The CUR-Mag-NLCs were developed as a particle with a size of 140 ± 3.6 nm, a polydispersity index of 0.196, and a zeta potential of −22.6 mV. VSM analysis showed that the CUR-Mag-NLCs have excellent magnetic properties. Release rate of the drug was higher at 42 °C than 37 °C, indicating that release of the synthesized nanoparticles is temperature-dependent. Evaluation of mitochondrial toxicity was done using the isolated rats liver mitochondria including glutathione (GSH), malondialdehyde (MDA), and the ferric- reducing ability of plasma (FRAP) assays to study biosafety of the CUR-Mag-NLCs. Results of In vitro study on the isolated mitochondria revealed that both CUR-Mag-NLCs and curcumin have no specific mitochondrial toxicity.

scholarly journals Importance and Antimicrobial Resistance of Mycoplasma bovis in Clinical Respiratory Disease in Feedlot Calves

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1470
Author(s):  
Ana García-Galán ◽  
Juan Seva ◽  
Ángel Gómez-Martín ◽  
Joaquín Ortega ◽  
Francisco Rodríguez ◽  
...  
Keyword(s):  
Respiratory Disease ◽  
Clinical Signs ◽  
Antimicrobial Treatment ◽  
Mycoplasma Bovis ◽  
Bacterial Disease ◽  
Feedlot Calves ◽  
Fixed Panel

Bovine respiratory disease (BRD) is an important viral and/or bacterial disease that mainly affects feedlot calves. The involvement of Mycoplasma bovis in BRD can lead to chronic pneumonia poorly responsive to antimicrobial treatment. Caseonecrotic bronchopneumonia is a pulmonary lesion typically associated with M. bovis. In Spain, M. bovis is widely distributed in the feedlots and circulating isolates are resistant to most antimicrobials in vitro. However, the role of this species in clinical respiratory disease of feedlot calves remains unknown. Furthermore, available data are relative to a fixed panel of antimicrobials commonly used to treat BRD, but not to the specific set of antimicrobials that have been used for treating each animal. This study examined 23 feedlot calves raised in southeast Spain (2016–2019) with clinical signs of respiratory disease unresponsive to treatment. The presence of M. bovis was investigated through bacteriology (culture and subsequent PCR), histopathology and immunohistochemistry. The pathogen was found in 86.9% (20/23) of the calves, mainly in the lungs (78.26%; 18/23). Immunohistochemistry revealed M. bovis antigens in 73.9% (17/23) of the calves in which caseonecrotic bronchopneumonia was the most frequent lesion (16/17). Minimum inhibitory concentration assays confirmed the resistance of a selection of 12 isolates to most of the antimicrobials specifically used for treating the animals in vivo. These results stress the importance of M. bovis in the BRD affecting feedlot calves in Spain.

Cytologic detection of Toxoplasma gondii in the cerebrospinal fluid of a dog and in vitro isolation of a unique mouse-virulent recombinant strain

2021 ◽  
pp. 104063872199668
Author(s):  
Waléria Borges-Silva ◽  
Mariana M. Rezende-Gondim ◽  
Gideão S. Galvão ◽  
Daniele S. Rocha ◽  
George R. Albuquerque ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Toxoplasma Gondii ◽  
Recombinant Strain ◽  
Neospora Caninum ◽  
Clinical Signs ◽  
Species Identity ◽  
Cytologic Examination ◽  
Pcr Rflp ◽  
Tissue Homogenates

Parasites resembling Neospora caninum or Toxoplasma gondii were detected by cytologic examination of cerebrospinal fluid (CSF) from a dog with neurologic disease. The dog became severely ill and was euthanized. Canine tissue homogenates were used for direct parasite isolation in cell culture, bioassay in 2 mouse lineages, and PCR. T. gondii was isolated in monkey kidney cells, and species identity was confirmed by PCR. Inoculated parasites were highly virulent for mice, which developed clinical signs and were euthanized immediately. PCR-RFLP for T. gondii using the cultured isolate (TgDgBA22) was conducted with 12 genetic markers, and a unique recombinant strain was identified. Detection of T. gondii by CSF cytology, although described in humans, had not been reported previously in dogs, to our knowledge, and was crucial for the diagnosis of toxoplasmosis in the examined dog.

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