scholarly journals Nanomedicine in Clinical Photodynamic Therapy for the Treatment of Brain Tumors

Biomedicines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 96
Author(s):  
Hyung Shik Kim ◽  
Dong Yun Lee

The current treatment for malignant brain tumors includes surgical resection, radiotherapy, and chemotherapy. Nevertheless, the survival rate for patients with glioblastoma multiforme (GBM) with a high grade of malignancy is less than one year. From a clinical point of view, effective treatment of GBM is limited by several challenges. First, the anatomical complexity of the brain influences the extent of resection because a fine balance must be struck between maximal removal of malignant tissue and minimal surgical risk. Second, the central nervous system has a distinct microenvironment that is protected by the blood–brain barrier, restricting systemically delivered drugs from accessing the brain. Additionally, GBM is characterized by high intra-tumor and inter-tumor heterogeneity at cellular and histological levels. This peculiarity of GBM-constituent tissues induces different responses to therapeutic agents, leading to failure of targeted therapies. Unlike surgical resection and radiotherapy, photodynamic therapy (PDT) can treat micro-invasive areas while protecting sensitive brain regions. PDT involves photoactivation of photosensitizers (PSs) that are selectively incorporated into tumor cells. Photo-irradiation activates the PS by transfer of energy, resulting in production of reactive oxygen species to induce cell death. Clinical outcomes of PDT-treated GBM can be advanced in terms of nanomedicine. This review discusses clinical PDT applications of nanomedicine for the treatment of GBM.

Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2104 ◽  
Author(s):  
Eleonora Ficiarà ◽  
Shoeb Anwar Ansari ◽  
Monica Argenziano ◽  
Luigi Cangemi ◽  
Chiara Monge ◽  
...  

Magnetic Oxygen-Loaded Nanobubbles (MOLNBs), manufactured by adding Superparamagnetic Iron Oxide Nanoparticles (SPIONs) on the surface of polymeric nanobubbles, are investigated as theranostic carriers for delivering oxygen and chemotherapy to brain tumors. Physicochemical and cyto-toxicological properties and in vitro internalization by human brain microvascular endothelial cells as well as the motion of MOLNBs in a static magnetic field were investigated. MOLNBs are safe oxygen-loaded vectors able to overcome the brain membranes and drivable through the Central Nervous System (CNS) to deliver their cargoes to specific sites of interest. In addition, MOLNBs are monitorable either via Magnetic Resonance Imaging (MRI) or Ultrasound (US) sonography. MOLNBs can find application in targeting brain tumors since they can enhance conventional radiotherapy and deliver chemotherapy being driven by ad hoc tailored magnetic fields under MRI and/or US monitoring.


2009 ◽  
Vol 110 (2) ◽  
pp. 289-299 ◽  
Author(s):  
Carlo Giussani ◽  
Franck-Emmanuel Roux ◽  
Lorenzo Bello ◽  
Valérie Lauwers-Cances ◽  
Costanza Papagno ◽  
...  

Object It has been hypothesized that specific brain regions involved in face naming may exist in the brain. To spare these areas and to gain a better understanding of their organization, the authors studied patients who underwent surgery by using direct electrical stimulation mapping for brain tumors, and they compared an object-naming task to a famous face–naming task. Methods Fifty-six patients with brain tumors (39 and 17 in the left and right hemispheres, respectively) and with no significant preoperative overall language deficit were prospectively studied over a 2-year period. Four patients who had a partially selective famous face anomia and 2 with prosopagnosia were not included in the final analysis. Results Face-naming interferences were exclusively localized in small cortical areas (< 1 cm2). Among 35 patients whose dominant left hemisphere was studied, 26 face-naming specific areas (that is, sites of interference in face naming only and not in object naming) were found. These face naming–specific sites were significantly detected in 2 regions: in the left frontal areas of the superior, middle, and inferior frontal gyri (p < 0.001) and in the anterior part of the superior and middle temporal gyri (p < 0.01). Variable patterns of interference were observed (speech arrest, anomia, phonemic, or semantic paraphasia) probably related to the different stages in famous face processing. Only 4 famous face–naming interferences were found in the right hemisphere. Conclusions Relative anatomical segregation of naming categories within language areas was detected. This study showed that famous face naming was preferentially processed in the left frontal and anterior temporal gyri. The authors think it is necessary to adapt naming tasks in neurosurgical patients to the brain region studied.


2011 ◽  
Vol 58 (1) ◽  
pp. 53-59
Author(s):  
Goran Tasic ◽  
Branislav Nestorovic ◽  
Ivan Milic ◽  
Igor Nikolic ◽  
Vladimir Jovanovic ◽  
...  

In spite of the progress made in diagnostic procedures and development of the operating rooms technology, considerable neurological deficit after operation of tumors localized in the brain motor zone commits one to direct intraoperative identification of the motor zone. By introducing direct electrocortical stimulation into the routine intraoperative application the primary goal has been achieved - reaching the maximum degree of radicalness of surgical resection while preserving motor centres in the cerebral cortex. Method: We are hereby demonstrating a series of 60 patients operated for primary brain tumors localized in the area in the front and around the central sulcus. All operations have been performed under the general anesthetics. During the operations the method of direct electrostimulation (ES) was used for the purpose of identifying motor centres. Results: Intraoperatively a level of subtotal resection was achieved in 22 cases, while radical resection was possible in 38 cases. Significantly higher level of radicalness of surgical resection of the low grade glioma tumor was confirmed statistically in relation to the group of patients with glioblastoma multiforme by applying the ES cortex (p<0,05). Patients with slow developing brain glioma have statistically considerably higher KI value in relation to the KI values in the group of patients with glioblastoma multiforme (p<0,01). Difference in the measured values of distance from the coronal suture based on the results of MRI measuring and finding obtained by ES, has shown a statistically considerably higher difference with glioblastoma multiforme 8,26+4,288mm when comapred to slowly developing astrocitoma 5,88+3,080 (p<0,05). Conclusion: Electrostimulation of the brain cortex is a safe, simple and precise method for identification of the brain motor zone which enables prevention of additional postoperative deficit and higher level of surgical radicalness.


2019 ◽  
Vol 63 (2) ◽  
pp. 285-292
Author(s):  
Ning Ma ◽  
Xin Li ◽  
Hong-bin Wang ◽  
Li Gao ◽  
Jian-hua Xiao

AbstractIntroduction:Tiletamine-xylazine-tramadol (XFM) has few side effects and can provide good sedation and analgesia. Adenosine 5’-monophosphate-activated protein kinase (AMPK) can attenuate trigeminal neuralgia. The study aimed to investigate the effects of XFM and its specific antagonist on AMPK in different regions of the brain.Material and Methods:A model of XFM in the rat was established. A total of 72 Sprague Dawley (SD) rats were randomly divided into three equally sized groups: XFM anaesthesia (M group), antagonist (W group), and XFM with antagonist interactive groups (MW group). Eighteen SD rats were in the control group and were injected intraperitoneally with saline (C group). The rats were sacrificed and the cerebral cortex, cerebellum, hippocampus, thalamus, and brain stem were immediately separated, in order to detect AMPKα mRNA expression by quantitative PCR.Results:XFM was able to increase the mRNA expression of AMPKα1 and AMPKα2 in all brain regions, and the antagonist caused the opposite effect, although the effects of XFM could not be completely reversed in some areas.Conclusion:XFM can influence the expression of AMPK in the central nervous system of the rat, which can provide a reference for the future development of anaesthetics for animals.


2021 ◽  
Vol 15 ◽  
Author(s):  
Jérôme Wahis ◽  
Matthew G. Holt

Noradrenaline is a major neuromodulator in the central nervous system (CNS). It is released from varicosities on neuronal efferents, which originate principally from the main noradrenergic nuclei of the brain – the locus coeruleus – and spread throughout the parenchyma. Noradrenaline is released in response to various stimuli and has complex physiological effects, in large part due to the wide diversity of noradrenergic receptors expressed in the brain, which trigger diverse signaling pathways. In general, however, its main effect on CNS function appears to be to increase arousal state. Although the effects of noradrenaline have been researched extensively, the majority of studies have assumed that noradrenaline exerts its effects by acting directly on neurons. However, neurons are not the only cells in the CNS expressing noradrenaline receptors. Astrocytes are responsive to a range of neuromodulators – including noradrenaline. In fact, noradrenaline evokes robust calcium transients in astrocytes across brain regions, through activation of α1-adrenoreceptors. Crucially, astrocytes ensheath neurons at synapses and are known to modulate synaptic activity. Hence, astrocytes are in a key position to relay, or amplify, the effects of noradrenaline on neurons, most notably by modulating inhibitory transmission. Based on a critical appraisal of the current literature, we use this review to argue that a better understanding of astrocyte-mediated noradrenaline signaling is therefore essential, if we are ever to fully understand CNS function. We discuss the emerging concept of astrocyte heterogeneity and speculate on how this might impact the noradrenergic modulation of neuronal circuits. Finally, we outline possible experimental strategies to clearly delineate the role(s) of astrocytes in noradrenergic signaling, and neuromodulation in general, highlighting the urgent need for more specific and flexible experimental tools.


Author(s):  
Sahib S. Khalsa ◽  
Justin S. Feinstein

A regulatory battle for control ensues in the central nervous system following a mismatch between the current physiological state of an organism as mapped in viscerosensory brain regions and the predicted body state as computed in visceromotor control regions. The discrepancy between the predicted and current body state (i.e. the “somatic error”) signals a need for corrective action, motivating changes in both cognition and behavior. This chapter argues that anxiety disorders are fundamentally driven by somatic errors that fail to be adaptively regulated, leaving the organism in a state of dissonance where the predicted body state is perpetually out of line with the current body state. Repeated failures to quell somatic error can result in long-term changes to interoceptive circuitry within the brain. This chapter explores the neuropsychiatric sequelae that can emerge following chronic allostatic dysregulation of somatic errors and discusses novel therapies that might help to correct this dysregulation.


1995 ◽  
Vol 1995 ◽  
pp. 204-204
Author(s):  
E.A. Azaga ◽  
R.G. Rodway

The long distance transport of sheep before slaughter is at present a very important topic in animal welfare. However, Modulation of opioid receptors can be influenced by chronic treatment with opioid agonists and antagonists (Blanchard, and Chang, 1988). Similarly, opioid receptors can be up or down-regulated by stressful stimuli such as restraint, electric footshock or social isolation and housing (Zeman et al., 1988 and Zanella et al., 1991). The present study was carried out to assess the effects of transport stress on the properties of one class of opioid peptide receptor in the brain of sheep after transport stress. Opioid peptides such as β-endorphin are released by the central nervous system during application of stresses such as transport. They are believed to exert analgesic properties and their effectiveness depends partly on the concentration (Bmax) and affinity (Kd) of their receptors. µ-Opioid receptors are found in various brain regions and are selective for endorphins and similar peptides.


2017 ◽  
Vol 34 (1) ◽  
pp. 23-35 ◽  
Author(s):  
Ju Hwan Kim ◽  
Da-Hyeon Yu ◽  
Hyo-Jeong Kim ◽  
Yang Hoon Huh ◽  
Seong-Wan Cho ◽  
...  

The exploding popularity of mobile phones and their close proximity to the brain when in use has raised public concern regarding possible adverse effects from exposure to radiofrequency electromagnetic fields (RF-EMF) on the central nervous system. Numerous studies have suggested that RF-EMF emitted by mobile phones can influence neuronal functions in the brain. Currently, there is still very limited information on what biological mechanisms influence neuronal cells of the brain. In the present study, we explored whether autophagy is triggered in the hippocampus or brain stem after RF-EMF exposure. C57BL/6 mice were exposed to 835 MHz RF-EMF with specific absorption rates (SAR) of 4.0 W/kg for 12 weeks; afterward, the hippocampus and brain stem of mice were dissected and analyzed. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis demonstrated that several autophagic genes, which play key roles in autophagy regulation, were significantly upregulated only in the hippocampus and not in the brain stem. Expression levels of LC3B-II protein and p62, crucial autophagic regulatory proteins, were significantly changed only in the hippocampus. In parallel, transmission electron microscopy (TEM) revealed an increase in the number of autophagosomes and autolysosomes in the hippocampal neurons of RF-EMF-exposed mice. The present study revealed that autophagy was induced in the hippocampus, not in the brain stem, in 835 MHz RF-EMF with an SAR of 4.0 W/kg for 12 weeks. These results could suggest that among the various adaptation processes to the RF-EMF exposure environment, autophagic degradation is one possible mechanism in specific brain regions.


PEDIATRICS ◽  
1953 ◽  
Vol 12 (5) ◽  
pp. 491-497 ◽  
Author(s):  
MARGARET H. D. SMITH ◽  
PAUL C. BEAVER

Two young mentally defective children were infected with a small number of embryonated eggs of the dog ascarid, Toxocara canis. They remained asymptomatic clinically but developed eosinophilia which persisted for more than 13 months. Tissues from mice infected experimentally with the same dose of dog ascarid eggs were examined at intervals up to one year after infection. In the early stages of infection the larvae were found principally in the liver and lungs, but in the later stages they were most numerous in the brain. It seems not improbable that some of the neurologic manifestations associated with ascariasis may be due to actual presence of Toxocara larvae in the tissues of the central nervous system, rather than to toxic or allergic effects of Ascaris lumbricoides. This new evidence, added to previous observations on the effect of dog and cat ascarids in children, re-emphasizes the need for ridding household pets of their intestinal parasites at frequent intervals.


2021 ◽  
Vol 66 (Special Issue) ◽  
pp. 70-71
Author(s):  
Duran Jaume ◽  
◽  

"According to different theories about neuroscience and ethics, we want to introduce the idea that the ethical values are very good levers to conduct human responses to their perceptions. These theories are based on very currently data about science and the central nervous system explained recently by a very important neuroscientist. In a very basic nervous system, the reptilian brain, humans can solve their fundamental interest and necessities, such as survival, breading, community behavior… In a more complex and posterior temporary nervous system, thanks to the known limbic brain, humans have been able to solve and to respond to their emotional problems, creating the memory center of our emotions. After this second moment and as a result of the global anthropological evolution, the cortical brain allows us to think, to deploy the global intelligences and take human decisions. Thanks to these three brain levels and their neurobiological connections, humans have developed other intangible brains, able to experience the ethics, the esthetics, and the spirituality. Our brain works as a whole. We are the result made up of more than 100.000 million connected neurons that form the brains. In some aspects, our four dimensions, the physical, the emotional, the rational and the transcendental faces act together, hand in hand. Our more ponderous decisions aren’t always rational; more than 80% of them are basically emotional. So, our spiritual manners can be showed by biophysically manifestations; conscientious and unconscientious affects us equally. Human brain is genetically prepared to answer. Historically formed to respond, the central nervous system can be explained as the most complex organ to produce responses to multiple previous perceptions. These perceptions can be tangible or not, external or internal, consciences or not, actual or memorized. Our point of view is that we can introduce ethical values as a non-conscientious response. Working from rational and emotional ways our ethical values, we will introduce them in our transcendental brain. All posterior relationship between the brain areas will influence the behavior response to the real perceptions that we are exposed to. So, to summarize, enforced ethical values can unconscientiously modify our behavioral response. "


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