Search results for "DAMAGE"

2013

Cortical function is impaired in various disorders of the central nervous system including Alzheimer’s disease, autism and schizophrenia. Some of these disorders are speculated to be associated with insults in early brain development. Pericytes have been shown to regulate neurovascular integrity in development, health and disease. Hence, precisely controlled mechanisms must have evolved in evolution to operate pericyte proliferation, repair and cell fate within the neurovascular unit (NVU). It is well established that pericyte deficiency leads to NVU injury resulting in cognitive decline and neuroinflammation in cortical layers. However, little is known about the role of pericytes in pathop…

Secondary Growth of a Primary Brain Tissue Necrosis from a Focal Lesion

1994

Traumatic brain injury is associated with the development of secondary brain damage, such as brain edema, intracranial hypertension, and cerebral ischemia [1]. A novel aspect is that a primary necrosis of brain parenchyma evolving from a focal cerebral insult may be subjected to secondary growth. Experiments utilizing different methods of brain injury have consistently confirmed an increase in size of the resulting tissue necrosis within 24 h, amounting to 50% in rats [3, 7, 10] and even 300% in rabbits [11]. It is not clear yet, however, whether the phenomenon reflects a delayed but irreversible primary process which is resistant to treatment or a manifestation of secondary brain damage, t…

Tissue microarray construction for salivary gland tumors study

2012

Objective: To describe and discuss the design, building and usefulness of tissue microarray (TMA) blocks for the study of salivary gland tumors (SGTs). Study Design: Two hundred thirty-eight formalin-fixed, paraffin-embedded SGTs were arranged in blocks of TMA using a manual tissue arrayer. Three representative cores of 1.0, 2.0 or 3.0mm were taken from each original block and their characteristics were analyzed and described. Results: It was created 12 TMA blocks that presented highly representative neoplastic cylinders. However, those neoplasias rich in cystic spaces such as mucoepidermoid carcinoma and Warthin tumor presented more difficulties to be sampled, as the neoplastic tissue avai…

The Blood–Brain Barrier as a Target in Traumatic Brain Injury Treatment

2014

Traumatic brain injury (TBI) is one of the most frequent causes of death in the young population. Several clinical trials have unsuccessfully focused on direct neuroprotective therapies. Recently immunotherapeutic strategies shifted into focus of translational research in acute CNS diseases. Cross-talk between activated microglia and blood–brain barrier (BBB) could initiate opening of the BBB and subsequent recruitment of systemic immune cells and mediators into the brain. Stabilization of the BBB after TBI could be a promising strategy to limit neuronal inflammation, secondary brain damage and acute neurodegeneration. This review provides an overview on the pathophysiology of TBI and brain…

DNA strand breaks induced by nuclear hijacking of neuronal NOS as an anti-cancer effect of 2-methoxyestradiol

2015

2-Methoxyestradiol (2-ME) is a physiological metabolite of 17β-estradiol. At pharmacological concentrations, 2-ME inhibits colon, breast and lung cancer in tumor models. Here we investigated the effect of physiologically relevant concentrations of 2-ME in osteosarcoma cell model. We demonstrated that 2-ME increased nuclear localization of neuronal nitric oxide synthase, resulting in nitro-oxidative DNA damage. This in turn caused cell cycle arrest and apoptosis in osteosarcoma cells. We suggest that 2-ME is a naturally occurring hormone with potential anti-cancer properties.

Pathological Findings in COVID-19 as a Tool to Define SARS-CoV-2 Pathogenesis. A Systematic Review

2021

Introduction: The World Health Organization declared the COVID-19 pandemic in March 2020. COVID-19 still represents a worldwide health emergency, which causesa severe disease that has led to the death of many patients. The pathophysiological mechanism of SARS-CoV-2 determining the tissue damage is not clear and autopsycan be auseful tool to improve the knowledge of this infection and, thus, it can help achieve a timely diagnosis and develop an appropriate therapy. This is an overview of the main post-mortem findings reporting data on the infection effects on several organs.Methods: A systematic literature search was conducted in the PubMed database searching for articles from 1 January to A…

Review: Neuroradiological aspects of infantile spasms

1987

With the modern noninvasive brain imaging methods, cerebral lesions of different types and degrees can frequently be determined in infants with West syndrome. In CT examinations preceding the spasms and the ACTH therapy, "idiopathic" forms of infantile spasms were rare. The CT findings consistent with perinatal or postnatal encephalopathy were more frequent than those found with embryonic or fetal lesions alone. The fact that pathognomonic changes cannot be determined, may reflect the low specificity of CT diagnosis in infants with chronic CNS diseases. A slight and mostly transient enlargement of CSF spaces during ACTH therapy is a probable side-effect of the medication. In infants with pe…

Induction of micronuclei in V79 Chinese hamster cells by tetrachlorohydroquinone, a metabolite of pentachlorophenol

1992

Tetrachlorohydroquinone, a metabolite of the fungicide pentachlorophenol, induced significant dose-related increases in micronuclei in V79 Chinese hamster cells without exogenous metabolic activation. The lowest observed effective dose was 10 microM, where the relative survival was about 62%. At the highest dose tested, 20 microM, the relative survival was about 8% and the frequency of cells with micronuclei was about 6 times the solvent control frequency. The induction of micronuclei by tetrachlorohydroquinone was significantly inhibited by the hydroxyl radical scavenger dimethyl sulfoxide at 5% (v/v).

Oxygen in the neonatal period: Oxidative stress, oxygen load and epigenetic changes

2020

Preterm infants frequently require positive pressure ventilation and oxygen supplementation in the first minutes after birth. It has been shown that the amount of oxygen provided during stabilization, the oxygen load, if excessive may cause hyperoxia, and oxidative damage to DNA. Epidemiologic studies have associated supplementation with pure oxygen in the first minutes after birth with childhood cancer. Recent studies have shown that the amount of oxygen supplemented to preterm infants after birth modifies the epigenome. Of note, the degree of DNA hyper-or hypomethylation correlates with the oxygen load provided upon stabilization. If these epigenetic modifications would persist, oxygen su…

Cytotoxic, immunomodulatory, antimycotic, and antiviral activities of semisynthetic 14-hydroxyabietane derivatives and triptoquinone C-4 epimers

2013

A series of C14-hydroxy derivatives of dehydroabietic acid were synthesised from commercial abietic acid and evaluated for their cytotoxic, antimycotic, and antiviral activities. From these C14-hydroxy derivatives, triptoquinone C-4 epimers were obtained and their immunomodulatory activity was additionally evaluated. None of the tested compounds showed antiviral activity against herpes simplex virus type 1 (HHV-1), and nor did they display antimycotic activity against certain Aspergillus, spp. except for one compound, abieta-8,11,13-trien-14,18-diol. Interestingly, two triptoquinone epimers showed cytotoxic activity, and one of them induced mitochondrial potential loss, DNA damage and cell …