BEHAVIOUR OF ADREN0CHR0ME PATHWAY IN PATIENTS WITH CEREBROVASCULAR DISEASES

1987 ◽  
Author(s):  
C Alessandri ◽  
F Violi ◽  
M Rasura ◽  
C Caliendo ◽  
P Pelaia
Keyword(s):  
Oxidase Activity ◽  
Brain Infarction ◽  
Preliminary Investigation ◽  
Significant Rise ◽  
Neutrophil Activation ◽  
Radical Mechanism ◽  
Toxic Substances ◽  
Plasma Adrenaline

Histopathological studies in segments of cerebral ischaemia show local inflammation with leucocytes infiltration.This event has been confirmed in vivo by means of radiolabelled leucocytes. This inflammatory response could be of detriment to cerebral tissue since leucocytes release toxic substances such as oxygen free radicals.A free radical mechanism,in fact,has been supposed as an event worsening the evolution of ischemia.Evidence of neutrophil activation in stroke patients was shown by us in previous reports, where we have described that the plasma of these patients contained an excess of a neutrophil oxidase able to convert,in vitro, adrenaline to adrenochrome.Aim of present study was to evaluate if neutrophil activation can be observed in patients with brain hemor ragie (BH) also.Six patients (females 1,males 5;age 68-79 years) suffering from BH and 15 patients (females 5, Males 10;age 58-86 years) affected by brain infarction (BI) were studied within 20-48 hours from acute episode.Diagnosis of stroke was made by computerized tomography.Neutrophil activation was studied in plasma evaluating the oxidation of adrenaline to adrenochrome according to Matthews and Campbell method.20 matched for age and sex healthy subjects were studied as control.A significant rise of plasma adrenaline oxidase activity was observed in patients with BI.This preliminary investigation suggests that neutrophil activation could be restricted to patients with BI.In fact,patients with BH had plasma oxidase activity similar to controls.Clinical data should be necessary to evaluate if a relation between leucocyte activation and the natural course of cerebral ischemia does exist.

scholarly journals 64Cu-ATSM/64Cu-Cl2 and their relationship to hypoxia in glioblastoma: a preclinical study

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Elodie A. Pérès ◽  
Jérôme Toutain ◽  
Louis-Paul Paty ◽  
Didier Divoux ◽  
Méziane Ibazizène ◽  
...  
Keyword(s):  
Ex Vivo ◽  
In Vitro Study ◽  
Tumor Location ◽  
Preclinical Study ◽  
Significant Rise ◽  
Lower Oxygen ◽  
Cu Complexes ◽  
Ex Vivo Study

Abstract Background Diacetyl-bis(N4-methylthiosemicarbazone), labeled with 64Cu (64Cu-ATSM) has been suggested as a promising tracer for imaging hypoxia. However, various controversial studies highlighted potential pitfalls that may disable its use as a selective hypoxic marker. They also highlighted that the results may be tumor location dependent. Here, we first analyzed uptake of Cu-ATSM and its less lipophilic counterpart Cu-Cl2 in the tumor over time in an orthotopic glioblastoma model. An in vitro study was also conducted to investigate the hypoxia-dependent copper uptake in tumor cells. We then further performed a comprehensive ex vivo study to compare 64Cu uptake to hypoxic markers, specific cellular reactions, and also transporter expression. Methods μPET was performed 14 days (18F-FMISO), 15 days (64Cu-ATSM and 64Cu-Cl2), and 16 days (64Cu-ATSM and 64Cu-Cl2) after C6 cell inoculation. Thereafter, the brains were withdrawn for further autoradiography and immunohistochemistry. C6 cells were also grown in hypoxic workstation to analyze cellular uptake of Cu complexes in different oxygen levels. Results In vivo results showed that Cu-ASTM and Cu-Cl2 accumulated in hypoxic areas of the tumors. Cu-ATSM also stained, to a lesser extent, non-hypoxic regions, such as regions of astrogliosis, with high expression of copper transporters and in particular DMT-1 and CTR1, and also characterized by the expression of elevated astrogliosis. In vitro results show that 64Cu-ATSM showed an increase in the uptake only in severe hypoxia at 0.5 and 0.2% of oxygen while for 64Cu-Cl2, the cell retention was significantly increased at 5% and 1% of oxygen with no significant rise at lower oxygen percentages. Conclusion In the present study, we show that Cu-complexes undoubtedly accumulate in hypoxic areas of the tumors. This uptake may be the reflection of a direct dependency to a redox metabolism and also a reflection of hypoxic-induced overexpression of transporters. We also show that Cu-ATSM also stained non-hypoxic regions such as astrogliosis.

scholarly journals Application of the 1-µsec pulsed-dye laser to the treatment of experimental cerebral vasospasm

1991 ◽  
Vol 75 (2) ◽  
pp. 271-276 ◽  
Author(s):  
Atsushi Teramura ◽  
Robert Macfarlane ◽  
Christopher J. Owen ◽  
Ralph de la Torre ◽  
Kenton W. Gregory ◽  
...  
Keyword(s):  
Cerebral Vasospasm ◽  
Basilar Artery ◽  
Laser Energy ◽  
Autologous Blood ◽  
Preliminary Investigation ◽  
Dye Laser ◽  
Pulsed Dye Laser ◽  
Content Type

✓ Laser energy of 480 nm was applied in 1-µsec pulses varying between 2.2 and 10 mJ to in vitro and in vivo models of cerebral vasospasm. First, the pulsed-dye laser was applied intravascularly via a 320-µm fiber to basilar artery segments from six dogs. The segments were mounted in a vessel-perfusion apparatus and constricted to, on average, 70% of resting diameter by superfusion with dog hemolysate. Immediate increase in basilar artery diameter occurred to a mean of 83% of control. In a second model, the basilar artery was exposed transclivally in the rabbit. In three normal animals, superfusion of the artery with rabbit hemolysate resulted in a reduction of mean vessel diameter to 81% of control. Following extravascular application of the laser, vessels returned to an average of 106% of the resting state. In six rabbits, the basilar artery was constricted by two intracisternal injections of autologous blood, 3 days apart. Two to 4 days after the second injection, the basilar artery was exposed. Extravascular laser treatment from a quartz fiber placed perpendicular to the vessel adventitia resulted in an immediate 53% average increase in caliber to an estimated 107% of control. No reconstriction was observed over a period of up to 5 hours. Morphologically, damage to the arterial wall was slight. This preliminary investigation suggests that the 1-µsec pulsed-dye laser may be of benefit in the treatment of cerebral vasospasm.

scholarly journals Novel polyisoprenyl phosphates block phospholipase D and human neutrophil activation in vitro and murine peritoneal inflammation in vivo

2005 ◽  
Vol 146 (3) ◽  
pp. 344-351 ◽  
Author(s):  
Bruce D Levy ◽  
Lorraine Hickey ◽  
Andrew J Morris ◽  
Mykol Larvie ◽  
Raquel Keledjian ◽  
...  
Keyword(s):  
Phospholipase D ◽  
Human Neutrophil ◽  
Neutrophil Activation ◽  
Peritoneal Inflammation

scholarly journals Neuroprotection by Brazilian Green Propolis againstIn vitroandIn vivoIschemic Neuronal Damage

2005 ◽  
Vol 2 (2) ◽  
pp. 201-207 ◽  
Author(s):  
Masamitsu Shimazawa ◽  
Satomi Chikamatsu ◽  
Nobutaka Morimoto ◽  
Satoshi Mishima ◽  
Hiroichi Nagai ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cerebral Ischemia ◽  
Neuronal Damage ◽  
Focal Cerebral Ischemia ◽  
Brain Infarction ◽  
Folk Medicine ◽  
Neuroprotective Function ◽  
Brazilian Green Propolis

We examined whether Brazilian green propolis, a widely used folk medicine, has a neuroprotective functionin vitroand/orin vivo.In vitro, propolis significantly inhibited neurotoxicity induced in neuronally differentiated PC12 cell cultures by either 24 h hydrogen peroxide (H2O2) exposure or 48 h serum deprivation. Regarding the possible underlying mechanism, propolis protected against oxidative stress (lipid peroxidation) in mouse forebrain homogenates and scavenged free radicals [induced by diphenyl-p-picrylhydrazyl (DPPH). In micein vivo, propolis [30 or 100 mg/kg; intraperitoneally administered four times (at 2 days, 1 day and 60 min before, and at 4 h after induction of focal cerebral ischemia by permanent middle cerebral artery occlusion)] reduced brain infarction at 24 h after the occlusion. Thus, a propolis-induced inhibition of oxidative stress may be partly responsible for its neuroprotective function againstin vitrocell death andin vivofocal cerebral ischemia.

scholarly journals THE EFFECTS OF SOME PESTICIDES ON REEF CORALS

1970 ◽  
Vol 17 ◽  
pp. 69-70
Author(s):  
Austin E. Lamberts
Keyword(s):  
Reef Coral ◽  
Chlorinated Hydrocarbons ◽  
In Vitro Studies ◽  
Toxic Substances ◽  
Reef Corals ◽  
Stress Effects ◽  
Skeletal Calcium

While investigating a reef coral kill in Samoa it was speculated that this might have been due to contamination by some chemical. Subsequently, scleractinian reef corals were tested to assess their reactions to 12 commonly used pesticides and toxic substances. The chlorinated-hydrocarbons such as DDT and Endrin produced stress effects in corals subjected to 2ppm for 24 hours in in-vitro studies although the corals continued to deposit skeletal calcium. In-vivo tank experiments suggested that small amounts of these substances in seawater stimulated the corals to deposit skeletal calcium. Other pesticides were much less toxic to the corals.

scholarly journals Neutrophil activation in vitro and in vivo in Wegener's granulomatosis

1994 ◽  
Vol 45 (4) ◽  
pp. 1120-1131 ◽  
Author(s):  
Elisabeth Brouwer ◽  
Minke G. Huitema ◽  
A.H. Leontine Mulder ◽  
Peter Heeringa ◽  
Harry van Goor ◽  
...  
Keyword(s):  
Wegener’S Granulomatosis ◽  
Wegener's Granulomatosis ◽  
Neutrophil Activation

scholarly journals DEVELOPMENT OF RITONAVIR LOADED NANOPARTICLES: IN VITRO AND IN VIVO CHARACTERIZATION

2018 ◽  
Vol 11 (3) ◽  
pp. 284
Author(s):  
Pravin S Patil ◽  
Shashikant C Dhawale
Keyword(s):  
Particle Size ◽  
Drug Release ◽  
Dissolution Rate ◽  
Drug Carrier ◽  
Entrapment Efficiency ◽  
Significant Rise ◽  
Scanning Calorimetry ◽  
In Vitro Drug Release

 Objective: The purpose of the present investigation was to develop a nanosuspension to improve dissolution rate and oral bioavailability of ritonavir.Methods: Extended-release ritonavir loaded nanoparticles were prepared using the polymeric system by nanoprecipitation technique. Further, the effect of Eudragit RL100 (polymeric matrix) and polyvinyl alcohol (surfactant) was investigated on particle size and distribution, drug content, entrapment efficiency, and in vitro drug release from nanosuspension where a strong influence of polymeric contents was observed. Drug-excipient compatibility and amorphous nature of drug in prepared nanoparticles were confirmed by Fourier transform infrared spectroscopy, differential scanning calorimetry, and powder X-ray diffraction studies, respectively.Results: Hydrophobic portions of Eudragit RL100 could result in enhanced encapsulation efficiency. However, increase in polymer and surfactant contents lead to enlarged particle size proportionately as confirmed by transmission electron microscopy. Nanosuspension showed a significant rise in dissolution rate with complete in vitro drug release as well as higher bioavailability in rats compared to the pure drug.Conclusion: The nanoprecipitation technique used in present research could be further explored for the development of different antiretroviral drug carrier therapeutics.

scholarly journals Kruppel-like factor 4 regulates neutrophil activation

2017 ◽  
Vol 1 (11) ◽  
pp. 662-668 ◽  
Author(s):  
Yuyan Shen ◽  
Hong Hong ◽  
Panjamaporn Sangwung ◽  
Stephanie Lapping ◽  
Lalitha Nayak ◽  
...  
Keyword(s):  
Crucial Role ◽  
Neutrophil Function ◽  
Neutrophil Activation ◽  
Key Points

Key Points KLF4 deficiency impairs neutrophil function in vitro and in vivo. This is the first demonstration that KLF4 plays a crucial role in neutrophils.

scholarly journals Microfluidics in male reproduction: is ex vivo culture of primate testis tissue a future strategy for ART or toxicology research?

2020 ◽  
Vol 26 (3) ◽  
pp. 179-192 ◽  
Author(s):  
Swati Sharma ◽  
Bastien Venzac ◽  
Thomas Burgers ◽  
Séverine Le Gac ◽  
Stefan Schlatt
Keyword(s):  
Male Infertility ◽  
Functional Organization ◽  
Ex Vivo ◽  
Significant Rise ◽  
Male Reproduction ◽  
Potential Applications ◽  
On Chip ◽  
Bio Engineering

Abstract The significant rise in male infertility disorders over the years has led to extensive research efforts to recapitulate the process of male gametogenesis in vitro and to identify essential mechanisms involved in spermatogenesis, notably for clinical applications. A promising technology to bridge this research gap is organ-on-chip (OoC) technology, which has gradually transformed the research landscape in ART and offers new opportunities to develop advanced in vitro culture systems. With exquisite control on a cell or tissue microenvironment, customized organ-specific structures can be fabricated in in vitro OoC platforms, which can also simulate the effect of in vivo vascularization. Dynamic cultures using microfluidic devices enable us to create stimulatory effect and non-stimulatory culture conditions. Noteworthy is that recent studies demonstrated the potential of continuous perfusion in OoC systems using ex vivo mouse testis tissues. Here we review the existing literature and potential applications of such OoC systems for male reproduction in combination with novel bio-engineering and analytical tools. We first introduce OoC technology and highlight the opportunities offered in reproductive biology in general. In the subsequent section, we discuss the complex structural and functional organization of the testis and the role of the vasculature-associated testicular niche and fluid dynamics in modulating testis function. Next, we review significant technological breakthroughs in achieving in vitro spermatogenesis in various species and discuss the evidence from microfluidics-based testes culture studies in mouse. Lastly, we discuss a roadmap for the potential applications of the proposed testis-on-chip culture system in the field of primate male infertility, ART and reproductive toxicology.

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