A Light Microscopy Study of the Migration of Naegleria fowleri from the Nasal Submucosa to the Central Nervous System during the Early Stage of Primary Amebic Meningoencephalitis in Mice

2000 ◽  
Vol 86 (1) ◽  
pp. 50 ◽  
Author(s):  
Kirby L. Jarolim ◽  
Jeffrey K. McCosh ◽  
Marsha J. Howard ◽  
David T. John
Microbiology ◽  
2017 ◽  
Vol 163 (10) ◽  
pp. 1436-1444 ◽  
Author(s):  
Charlton Lam ◽  
Melissa Jamerson ◽  
Guy Cabral ◽  
Ana Maris Carlesso ◽  
Francine Marciano-Cabral

Author(s):  
Gladys Harrison

With the advent of the space age and the need to determine the requirements for a space cabin atmosphere, oxygen effects came into increased importance, even though these effects have been the subject of continuous research for many years. In fact, Priestly initiated oxygen research when in 1775 he published his results of isolating oxygen and described the effects of breathing it on himself and two mice, the only creatures to have had the “privilege” of breathing this “pure air”.Early studies had demonstrated the central nervous system effects at pressures above one atmosphere. Light microscopy revealed extensive damage to the lungs at one atmosphere. These changes which included perivascular and peribronchial edema, focal hemorrhage, rupture of the alveolar septa, and widespread edema, resulted in death of the animal in less than one week. The severity of the symptoms differed between species and was age dependent, with young animals being more resistant.


Life ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 300
Author(s):  
Petr Kelbich ◽  
Aleš Hejčl ◽  
Jan Krejsek ◽  
Tomáš Radovnický ◽  
Inka Matuchová ◽  
...  

Extravasation of blood in the central nervous system (CNS) represents a very strong damaged associated molecular patterns (DAMP) which is followed by rapid inflammation and can participate in worse outcome of patients. We analyzed cerebrospinal fluid (CSF) from 139 patients after the CNS hemorrhage. We compared 109 survivors (Glasgow Outcome Score (GOS) 5-3) and 30 patients with poor outcomes (GOS 2-1). Statistical evaluations were performed using the Wilcoxon signed-rank test and the Mann–Whitney U test. Almost the same numbers of erythrocytes in both subgroups appeared in days 0–3 (p = 0.927) and a significant increase in patients with GOS 2-1 in days 7–10 after the hemorrhage (p = 0.004) revealed persistence of extravascular blood in the CNS as an adverse factor. We assess 43.3% of patients with GOS 2-1 and only 27.5% of patients with GOS 5-3 with low values of the coefficient of energy balance (KEB < 15.0) in days 0–3 after the hemorrhage as a trend to immediate intensive inflammation in the CNS of patients with poor outcomes. We consider significantly higher concentration of total protein of patients with GOS 2-1 in days 0–3 after hemorrhage (p = 0.008) as the evidence of immediate simultaneously manifested intensive inflammation, swelling of the brain and elevation of intracranial pressure.


2006 ◽  
Vol 51 (1) ◽  
pp. 23-27 ◽  
Author(s):  
Shannon M. Soltow ◽  
George M. Brenner

ABSTRACT Naegleria fowleri is responsible for producing a rapidly fatal central nervous system infection known as primary amebic meningoencephalitis (PAM). To date, amphotericin B, an antifungal agent, is the only agent with established clinical efficacy in the treatment of PAM. However, amphotericin B is not always successful in treating PAM and is associated with severe adverse effects. We previously found azithromycin to be more effective than amphotericin B in a mouse model of PAM. We therefore investigated the combination of amphotericin B and azithromycin in vitro and in a mouse model of PAM. For the in vitro studies, 50% inhibitory concentrations were calculated for each drug alone and for the drugs in fixed combination ratios of 1:1, 3:1, and 1:3. We found amphotericin B and azithromycin to be synergistic at all three of the fixed combination ratios. In our mouse model of PAM, a combination of amphotericin B (2.5 mg/kg of body weight) and azithromycin (25 mg/kg) protected 100% of the mice, whereas amphotericin B alone (2.5 mg/kg) protected only 27% of mice and azithromycin alone (25 mg/kg) protected 40% of mice. This study indicates that amphotericin B and azithromycin are synergistic against the Lee strain of N. fowleri, suggesting that the combined use of these agents may be beneficial in treating PAM.


1970 ◽  
Vol 7 (5) ◽  
pp. 435-447 ◽  
Author(s):  
K. M. Charlton ◽  
K. R. Pierce ◽  
R. W. Storts ◽  
C. H. Bridges

Twenty-two goats were poisoned with daily oral doses of ground coyotillo fruits and were killed at various times after the first day of dosing. The morphologic features and distribution of lesions in the central nervous system were studied by light microscopy. An axonal dystrophy occurred in several of the goats given high daily doses. Swellings occurred along axons of Purkinje cells in the cerebellum and in the white matter of the spinal cord. There was a fairly close correlation between the occurrence of clinical signs suggestive of the neocerebellar syndrome and the occurrence and distribution of lesions in the cerebellum.


2021 ◽  
Vol 8 (4) ◽  
pp. 73-76
Author(s):  
Katherine Figarella

Trypanosoma brucei is one of the protozoa parasites that can enter the brain and cause injury associated with toxic effects of parasite-derived molecules or with immune responses against infection. Other protozoa parasites with brain tropism include Toxoplasma, Plasmodium, Amoeba, and, eventually, other Trypano-somatids such as T. cruzi and Leishmania. Together, these parasites affect billions of people worldwide and are responsible for more than 500.000 deaths annually. Factors determining brain tropism, mechanisms of in-vasion as well as processes ongoing inside the brain are not well understood. But, they depend on the par-asite involved. The pathogenesis caused by T. brucei initiates locally in the area of parasite inoculation, soon trypanosomes rich the blood, and the disease enters in the so-called early stage. The pathomecha-nisms in this phase have been described, even mole-cules used to combat the disease are effective during this period. Later, the disease evolves towards a late-stage, characterized by the presence of parasites in the central nervous system (CNS), the so-called meningo-encephalitic stage. This phase of the disease has not been sufficiently examined and remains a matter of investigation. Here, I stress the importance of delve into the study of the neuropathogenesis caused by T. brucei, which will enable the identification of path-ways that may be targeted to overcome parasites that reached the CNS. Finally, I highlight the impact that the application of tools developed in the last years in the field of neuroscience will have on the study of neglect-ed tropical diseases.


2020 ◽  
Vol 8 (6) ◽  
pp. 1146-1149

This note explains about “Parkinson Disease which may be a long-term disorder of the central nervous system”. The research paper focuses on analysis of symptoms of “Parkinson Disease” to predict the disease in early stage. Concept of FCMs was used to interpret the diagnostic symptoms of “Parkinson Disease”. The target is to draw connection between the symptoms and provide likely explanation.


2005 ◽  
Vol 17 (6) ◽  
pp. 605-609 ◽  
Author(s):  
Barbara M. Daft ◽  
Govinda S. Visvesvara ◽  
Deryck H. Read ◽  
Hailu Kinde ◽  
Francisco A. Uzal ◽  
...  

Primary amoebic meningoencephalitis is a fulminant infection of the human central nervous system caused by Naegleria fowleri, a free-living amoeba that thrives in artificially or naturally heated water. The infection usually is acquired while bathing or swimming in such waters. The portal of entry is the olfactory neuroepithelium. This report describes fatal meningoencephalitis caused by N. fowleri in Holstein cattle that consumed untreated surface water in an area of California where summer temperatures at times exceed 42°C. In the summers of 1998 and 1999, severe multifocal necrosuppurative hemorrhagic meningoencephalitis was observed in brain samples from nine 10-20-month-old heifers with clinical histories of acute central nervous system disease. Olfactory lobes and cerebella were most severely affected. Lesions were also evident in periventricular and submeningeal neuropil as well as olfactory nerves. Naegleria fowleri was demonstrated by immunohistochemistry in brain and olfactory nerve lesions and was isolated from one brain. Even though cultures of drinking water did not yield N. fowleri, drinking water was the likely source of the amoeba. The disease in cattle closely resembles primary amoebic meningoencephalitis in humans. Naegleria meningoencephalitis should be included among differential diagnoses of central nervous system disease in cattle during the summer season in areas with high ambient temperatures.


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