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Basal cell carcinoma (BCC) is a common, locally invasive tumor that arises within sun-damaged skin and rarely develops on the palms and soles or mucous membranes. Men generally have higher rates of BCC than women. Incidence also increases with age and the median age of diagnosis is 68 years old. Mortality from BCC is rare and cases of aggressive, local destructive, metastatic BCCs are more likely from tumors with aggressive histopathological (HP) patterns. The aim of this study was to investigate and correlate the immunohistochemical expression of p53, Ki67, alpha-smooth muscle actin (α-SMA), cluster of differentiation (CD)44 and CD31 with both aggressive and nonaggressive types of BCCs. In our study, we observed a varied staining pattern for p53, with the highest reactivity noticed in the peripheral palisading zone. The staining pattern for Ki67 was similar to p53, with a more pronounced reaction in the periphery of the tumor. We found different Ki67 and p53 expression among the various subtypes of BCC. The CD31 reactivity, mostly seen in the stroma, was positive in all BCCs and varied significantly between its different HP subtypes. Regarding stromal expression of α-SMA, the adenoid and basosquamous types had the most intense reaction in our study. The CD44 tumor expression was correlated in our study to the aggressive pattern of BCCs.

Hepatocellular carcinoma (HCC) is the main primary liver malignancy, being associated with both health and economic burden worldwide. Recently, novel molecular markers and possible therapeutic targets were identified. Different adhesion molecules, as well as possible angiogenesis-associated targets can be prime candidates when investigating novel therapies. Considering these premises, our goal was to study the co-existence of E-cadherin and aquaporin 1 (AQP1) in a series of HCC diagnosed patients. Utilizing archived tissue fragments from 17 patients diagnosed with well-to-moderate and poorly differentiated HCC, as well as four samples of normal liver tissue and using a highly specific biotin-free tyramide amplification technique, we have assessed here the expression of E-cadherin and AQP1 during HCC carcinogenesis. Moreover, as we have observed that some of the AQP1 expression seems membrane-bound, we have sought to evaluate their co-localization. Our data showed, as expected, that E-cadherin decreases from control tissue to low-grade and respectively, high-grade HCC. AQP1 was expressed, also as already known, at the level of endothelial blood vessels and bile ducts epithelia, however, we have showed here for the first time that this water pore is also expressed in the cytoplasm and membranes of hepatocytes, both in control and HCC tissue. Moreover, AQP1 expression parallels the decrease of E-cadherin expression during carcinogenesis, but together with this downregulation, we have also found a spatial decrease in the colocalization of the two proteins. Altogether, utilizing a biotin-free tyramide signal amplification technique, this study shows for the first time that AQP1 is expressed at the level of liver epithelia, in both control and HCC tissue.

Two deep-learning algorithms designed to classify images according to the Gleason grading system that used transfer learning from two well-known general-purpose image classification networks (AlexNet and GoogleNet) were trained on Hematoxylin-Eosin histopathology stained microscopy images with prostate cancer. The dataset consisted of 439 images asymmetrically distributed in four Gleason grading groups. Mean and standard deviation accuracy for AlexNet derivate network was of 61.17±7 and for GoogleNet derivate network was of 60.9±7.4. The similar results obtained by the two networks with very different architecture, together with the normal distribution of classification error for both algorithms show that we have reached a maximum classification rate on this dataset. Taking into consideration all the constraints, we conclude that the resulted networks could assist pathologists in this field, providing first or second opinions on Gleason grading, thus presenting an objective opinion in a grading system which has showed in time a great deal of interobserver variability.

Atypical meningiomas with a mixed glial-epithelial phenotype are rare reports, and here we described an aggressive case on which double immunofluorescence ascertained the co-expression of epithelial membrane antigen (EMA) with glial fibrillary acidic protein (GFAP) in the same tumor cells. A 62-year-old female presented with acute intracranial hypertension symptoms occurred over the last 24 hours, muscle weakness on the right side, cerebellar dysarthria, and wide base gate. Magnetic resonance imaging (MRI) examination showed a right cerebellar hemisphere non-homogenous tumor, with intense gadophylia, diffuse contours, and necrotic inner areas. There were also scar-like areas at the level of the left cerebellar hemisphere, and the patient recalled a previous surgical intervention at the age of 6 years old without further diagnostic data. The patient suffered an ischemic event in the brain stem and died shortly after the surgical removal of the tumor. Histopathology revealed an epithelial-like tumor with moderately pleomorphic and elongated cells arranged in fascicles, rare necrotic areas, and a few proliferating multilayered vessels structures. Immunohistochemistry (IHC) revealed variable EMA positivity, intense vimentin staining, rare GFAP-positive intra-tumor areas, a moderate expression for cytokeratin 8/18, reduced labeling for an anti-progesterone receptor (PrgR) antibody, cluster of differentiation (CD) 10 negativity, and a high Ki-67 proliferating index of around 40%. The case was deemed as an atypical meningioma, and interestingly, a double IHC for GFAP∕EMA revealed a strong colocalization of the two markers in the tumor mass. Although extremely rare, the reports of meningiomas expressing a mixed epithelial∕glial profile might be connected with their aggressive evolution. Double IHC might help in predicting the evolution of these cases and determine which patients should benefit from closer surveillance.

Ischemic stroke occurs through embolic or thrombotic obliteration of an artery from cerebral circulation and represents over 80% of all stroke cases. One of the fiercest complications after stroke is edema, which results from imbalanced water diffusion around the blood vessels walls. Water diffusion around blood vessel walls occurs physiologically mainly through two protein-formed pores, namely aquaporins (AQPs) 1 and 4. Here, we compare for the first time the expression patterns and colocalization degrees of the two AQPs in control brain tissue and in peri-ischemic regions, on tissue obtained from eight patients with confirmed ischemic pathology and from five control cases. Our analysis showed that AQP4 is more abundant that AQP1, especially in the cortex and in the organized scar areas. The colocalization of the two markers was high, both located on the astrocytes membranes, but the colocalization degree decreased in the scar peri-ischemic regions. Colocalization with basement membranes was also lower for AQP1 compared to AQP4, in all regions analyzed.

Multiple sclerosis (MS) is a complex chronic neurodegenerative disease that involves an abnormal autoimmune response directed against the brain, nerves and spinal cord; it is considered the most frequent cause of neurological disability, because MS-associated inflammatory lesions can affect a wide range of systems to a varying degree and may cause a plethora of neurological comorbidities and symptoms. The symptoms are quite variable from patient to patient and depend on the spatial distribution of the central nervous system (CNS) lesions, but usually involve sensory disturbances, cognitive deficits, unilateral vision loss, bladder dysfunction, ataxia, fatigue, double vision, weakness of the limbs and intestinal disorders. Experimental autoimmune encephalitis (EAE) mouse model reproduces the pathological features of the human disease, and is a widely used model used for studying the pathology and different treatment options in the preclinical stage. In this study, we aimed to evaluate the motor function, as well as the degree of demyelination and inflammatory changes in the brains of mice immunized for the myelin oligodendrocyte glycoprotein (MOG)35-55, and treated with Cerebrolysin. Animals were randomly assigned to one of the three groups: (i) EAE untreated group (n=10), (ii) EAE treated group (n=10), and (iii) control group (n=5), and their motor dysfunction was followed until the clinical pathology begun to improve. We also analyzed histologically and immunohistochemically the lesions in the optical nerves, cervical spinal cord and medulla. Our results showed higher deficit scores for untreated animals compared to treated animals. After harvesting the tissue, we have first evaluated the density of myelin in the optical nerves, cervical spinal cord and medulla and we found significant differences between treated and untreated groups of animals. We continued to investigate the structure of the CNS parenchyma by evaluating the intensity and morphology of the neuronal cytoskeleton and microglia by immunohistochemical stainings. Although larger animal groups are necessary, this is the first pilot study to investigate the use of a neurotrophic factor as a putative treatment option for a MS model.

Liver fibrosis is one of the most serious histopathological (HP) lesions that, together with the inflammatory process and the hepatocyte lesions, determine the change of the liver architecture, having as a clinical result the onset of liver failure phenomena. Hepatitis C virus represents one of the most frequent conditions leading to the onset of liver fibrosis and favors the progression of the disease towards hepatocellular carcinoma. We evaluated the HP and immunohistochemical (IHC) aspects on fragments of liver biopsies taken from 104 patients diagnosed with chronic hepatitis C and altered capacity of work. In our study, we observed a growth of the portal (Kiernan) spaces by the presence of a chronic inflammatory infiltrate, the presence of collagen fibers and conjunctive matrix. The density and dimensions of collagen fibers were correlated with the severity of the liver disease, in the severe forms being highlighted porto-portal and porto-central fibrous bridges. The IHC examinations highlighted the change of the phenotype of perisinusoidal dendritic cells, the growth of the myofibroblast cells in the portal spaces, the growth of the macrophage number in the inflammatory infiltrate and of the Kupffer cells in the liver parenchyma.

Helicobacter pylori (HP) infection is one of the most frequent bacterial infections in humans. The studies performed in the last 30 years showed that this bacterium is the main cause of chronic gastritis and the main etiological agent of peptic ulcer and gastric cancer. We investigated the prevalence of HP infection in a group of 1525 patients who addressed a gastroenterology medical center between 2010-2014, in Craiova, Romania, for dyspeptic symptoms. The patients underwent a clinical, endoscopic and serologic investigation for highlighting a possible HP infection. The age of the patients with gastric duodenal pathology varied between 16 and 87 years old. Of the 1525 patients, a number of 971 (63.67%) were diagnosed with HP infection, while the rest of 554 (36.33%) were not infected. The study on the distribution of gastric duodenal pathology and HP infection showed that the lesions of the upper digestive tract and HP infection emerged quite early, a number of 29 patients being aged less than 20 years old; among these, 21 (72.41%) patients were HP positive and only eight (27.59%) were HP negative. In the age group of 20-29 years old there were recorded 184 patients, of which 120 (65.22%) were HP positive and only 64 (34.78%) were HP negative. There may be observed that in the age group of 20-29 years old, both the patients with gastric duodenal pathology and the ones with HP infection increased six times in comparison to the first decade. Most cases were recorded in the patients aged between 50 and 69 years old. The two decades comprised a total number of 607 (39.8%) patients, of which 375 (61.78%) were HP positive and 232 (38.22%) were HP negative. By evaluating the distribution of HP infection according to the social environment, there was observed that there were no significant differences between the patients coming from the urban area and the ones from the rural area, as far as the HP infection was concerned.

The study of rare, inherited forms of different diseases resulted in the discovery of gene defects that cause inherited variants of the respective diseases. The defective genes were found to encode major molecular players leading to the neuropathological lesions or factors that characterize these diseases. The exact role of the tau protein in the neurodegenerative process is still under debate. It is very important to understand the normal biological roles of tau and the specific events that induce tau to become neurotoxic. Tau is the major microtubule-associated protein (MAP) of a mature neuron. The other neuronal MAPs are MAP1 and MAP2. These three MAPs perform similar function, promoting assembly and stability of microtubules. Tau protein was isolated as a microtubule-associated factor in the porcine brain. It was isolated as a protein that co-purified with tubulin and had the ability to promote microtubule assembly in vitro. Normal adult human brain tau contains 2-3 moles phosphate÷mole of tau protein. Hyperphosphorylation of tau depress this biological activity of tau. Almost 80 diseases caused by missense mutations and intronic mutations in the tau gene have been found in familial cases of frontotemporal dementia (FTD). In Alzheimer's disease (AD), there are intraneuronal neurofibrillary tangles composed of the microtubule-associated protein tau (MAPT). In other neurodegenerative diseases, there are similar deposits of tau, in the absence of extracellular deposits (progressive supranuclear palsy, corticobasal degeneration, argyrophilic grain disease, etc.). Tau pathology is also often seen in some forms of Parkinson's disease (PD) and prion diseases. In genetic forms of FTD, mutations in tau implicate abnormal tau as the initiation of neurodegeneration. In FTD, there are deposits especially in temporal and frontal lobes, regions that are very important for behavior and executive function. It is critical to understand how tau becomes pathogenic, in order to consider developing any strategies for treatment.

Stroke is one of the most important cause of death and disability, especially when considering the increasing life expectancy worldwide, with ischemic stroke being much more common than hemorrhages. In the physiopathological chain of ischemic stroke, brain edema is one first element that if attended to might reduce tissue necrosis, penumbra, and increase functional recovery. Aquaporin 4 (AQP4) has been found to be the most important water channel in the brain, and its inhibition before inducing focal ischemia in an animal model of stroke proved to alleviate the pathology and improve clinical recovery. In this study, we have treated a rat model of ischemic stroke with the AQP4 inhibitor TGN-020 after inducing the lesion, and performed for the first time a direct histopathological evaluation of the brain and infarct's volume. Besides utilizing immunohistochemistry targeting the growth-associated protein-43 (GAP-43) in order to delineate the infarct regions, we have used the Cavalieri's principle of tissue volume measurements starting form seriate sections, and for the first time in neuropathology, we have utilized a high-resolution object scanner to assess global brain volume changes. Our results showed that TGN-020 clearly reduces infarct volume in TGN-020 treated animals compared to untreated animals, as well as the volume of the brain hemispheres. Although reduced, the effect was also present in the contralateral hemisphere. Given these data, a more in-depth characterization of the histopathological and molecular changes induced by AQP-4 are needed for considering it as a bona fide treatment option.

Multiple primary central nervous system tumors are rarely seen in clinical practice and reported in the literature. The pathogenesis of multicentricity of primary tumors of the central nervous system still remains a debate, this pathology being found in almost two percent of reported tumor cases. Multifocal tumors are often described within the same hemisphere and supposed to be disseminated along the white matter tracts. On the opposite, multicentric tumors are found in the other hemisphere in subtentorial structures and are considered synchronous. We illustrate here the case of a young man admitted for symptoms of intracranial hypertension, diagnosed with multifocal and multicentric low-grade oligoastrocytoma with particular evolution and imagistic appearance.

Introduction: It has been suggested that desmin cytoskeleton remodeling may contribute to the progression of dilated cardiomyopathy and might affect long-term prognosis. This study is aiming at evaluating desmin expression in cardiomyocytes from patients with dilated cardiomyopathy of alcoholic etiology in advanced stages of the disease and comparing the results with measurements of normal heart tissue from control patients., Materials and Methods: For immunohistochemistry, sections from 36 myocardium fragments taken from left ventricle of dilated cardiomyopathy patients were immunolabeled with an anti-desmin antibody and negative control slides were obtained by omitting the primary antibody. We calculated the ratios between the areas of myocardiocytes and the length and number of A dark disks and assessed the desmin expression level as the integrated optical density (IOD) and, respectively, the total areas of the signal given by immunolabeling. A Student's t-test has been utilized to assess the differences, p<0.05 deemed significant data., Results: We identified significant decrease in numerical density of dark disks in our cases group compared with controls (p<0.05). Also, the ratios between total cellular area and total length of dark disks and number of dark disks was significantly different between cases and controls (p=0.04). IOD was significantly different between dilative cardiomyopathy cases and controls and also, overall desmin expression area was increased in dilatative cardiomyopathy patients., Conclusions: The identification of different desmin expression and standardization in diseased myocardium may be helpful in stratifying patients and in understanding their evolution, but also in finding new therapeutic targets that aim the alterations in desmin expression.

This work was aimed to analyze the versatility of the chick embryo chorioallantoic membrane (CAM) as in vivo model for the study of the malignant pleural mesothelioma (MPM) and the therapeutic potential of Fe3O4÷salicylic acid magnetic nanoparticles (SaMNPs) on MPM cells. The antitumor effects of SaMNPs were studied by in vitro and in vivo tests on CARM-L12 TG3 rat malignant mesothelioma cells and human MPM xenografts implanted on CAMs. In order to assess the human MPM xenograft growth characteristics, calretinin, HBME-1 (Hector Battifora mesothelial epitope-1), and cytokeratins immunohistochemical stainings were performed. The human MPM xenografts continue to develop on the CAMs and xenograft MPM cells showed highly metastatic features and a particular pattern of metastasis. The SaMNPs had a specific uptake by the MPM cells and an antiproliferative effect at therapeutic doses greater than 100 μg÷mL. The results confirmed the possibility to use the CAM as in vivo model to study the biology of MPM and to evaluate the antitumor potential of new therapeutic agents. They highlighted a strong antitumor effect of the SaMNPs on the rat and human MPM cells and open new perspectives in the treatment of MPM.

Myocardial fibrosis is one of the most common histopathological lesions found in chronic heart diseases. Progressive development of myocardial fibrosis will cause heart failure, an extremely debilitating and life threatening condition. The correlation between the severity of fibrosis and myocardial microcirculation is an important prognostic factor in this disease entity. In our study, myocardial microvascular density evaluation of the patients with high blood pressure (hypertension), atrial fibrillation (AF), coronary heart disease, and heart failure showed a significant decrease of the values of this parameter, which means that myocardial fibrosis is the direct result of stimulation of myocardial fibroblasts induced by local hypoxia.

Basal cell carcinoma is the most common malignant tumor of the skin, and it develops most frequently on the areas of the body that make its treatment and care extremely difficult, especially in cases of neglecting or aggressive growth and invasion. Both typical mild cases as well as locally aggressive tumor types do not tend to metastasize, and it has been postulated that they should share some common biological and morphological features that might explain this behavior. In this study, we have utilized a high-resolution three-dimensional reconstruction technique on pathological samples from 15 cases of common aggressive (fibrosing and adenoid types) and mild (superficial type) basal cell carcinomas, and showed that all these types shared contact points and bridges with the underlying basal cell layer of the epidermis or with the outmost layer of the hair follicle. The connections found had in fact the highest number for fibrosing type (100%), compared to the superficial (85.71%) and adenoid (55%) types. The morphology of the connection bridges was also different, adjacent moderate to abundant inflammatory infiltrate seeming to lead to a loss of basaloid features in these areas. For the adenoid type, tumor islands seemed to be connected also to each other more strongly, forming a common "tumor lace", and while it has been showed that superficial and fibrosing types have higher recurrence risks, all together these data might iterate a connection between the number of bridging points and the biological and clinical manifestation of this skin tumor.

The eyelids represent a frequent site for numerous malignant tumors, which generally present subtle symptoms or can imitate benignant tumors. Our study was carried on 80 patients, 48 males and 32 females aged between 48 and 92 years. The patients were hospitalized in the Ophthalmology Clinic of the Emergency County Hospital of Craiova, Romania. The study was conducted over five years, between 2010 and 2014. Our study included 80 basal cell carcinomas of the eyelids, of which 48 (60%) were nodular basal cell carcinomas, 15 (18.75%) were adenoid basal cell carcinomas, 10 (12.5%) were cystic and seven (8.75%) were morpheaform basal cell carcinoma. Our study showed a moderate expression of bcl-2 marker in the nodular type of basal cell carcinoma and a high expression in the other histopathological types, thus inducing an increased malignancy comparing to the nodular type. E-cadherin was absent in nodular, cystic and adenoid basal cell carcinomas and had a moderate expression in morpheaform basal cell carcinoma. Morpheaform and adenoid types presented 20% expression of Ki67 of the malignant cells nuclei, while the cystic type presented Ki67 expression in less than 10% of the malignant cells nuclei. Due to high morbidity and increasing incidence, basal cell carcinoma of the eyelid represents an important health issue nowadays.

Corpora amylacea (CA) are glycoprotein-based depositions that accumulate in the normal aging brain or consecutively to different neuro-degenerative diseases. Although controversies still exists in what it regards their origins and functions, their morphology is described simply as round basophilic entities based on bi-dimensional observations. The aim of the present study was to evaluate the three-dimensional morphology of these bodies in the brain in normal aging. We utilized here brain tissue from six aged patients, and performed an in-depth stereological analysis of CAs based on series of thin serial sections, and 50 μm-thick sections. The thin seriate sections have been counter-stained with Hematoxylin and Eosin, while the thick sections have been immunostained in fluorescence for ubiquitin and GFAP/collagen IV or aquaporin 4. Three-dimensional renderings have been obtained after aligning the serial sections, while high-resolution z-stacks have resulted after deconvolution on the thick sections. More than 70% of all the identified CAs proved to be in fact parts of larger aggregates, where the flattened individual spheroids branched and communicated with other bodies in a complex pattern, and budding of small CAs from larger CAs could be observed. There was a direct correlation between the diameter of the vessels and the number of associated CAs. Astrocyte GFAP and aquaporin 4 signals surrounded CAs, but without any colocalization with the ubiquitin areas, while perivascular CAs were sometimes enclosed in pockets of the basement membranes. In conclusion, as far as we know, this is the first study to describe the three-dimensional branching complexity of corpora amylacea in the brain.

Although already in use in several medical domains, only recently optical coherence tomography (OCT) has been applied in the study of ischemic events. In this paper, we will focus on characterizing ischemic stroke, in a rat model, by OCT. Investigations were carried on a set of 25 rats, on which ischemic stroke was inflicted by a transient occlusion of the middle cerebral artery (tMCAO). Animals were sacrificed 1, 3, 7 and 28 days after occlusion. We tested the OCT's power of detection and discrimination of stroke area compared to both normal, contralateral hemisphere and non-affected brain tissue, together with the aid of histochemical and pathological examination. Our results show a great potential of OCT to be used as a detection tool in acute and chronic phases of stroke.

Basal cell carcinoma is the most common malignant tumor of the skin, and it develops most frequently on the head and neck regions. Although most of these tumors are slow growing and with a limited evolution, the existence of some aggressive variants accompanied by a complete neglect from the patient may occasionally lead to invasion of the face and organs of the head and neck. Even though, intracranial invasion of basal cell carcinoma of the scalp is a rare presentation. We describe here the case of a woman who developed an aggressive and neglected morpheiform basal cell carcinoma (ulcus terebrans), which showed a complete invasion through the skull, but with an apparent self-limitation to the pia mater.

As heart development is an incomplete described area, and likewise an important source of intra- and post-partum morbidity and mortality, we have aimed at analyzing both vascular and cytoskeletal factors during early heart development in humans. The distribution of CD105, CD31, α-SMA, vimentin and desmin have been studied on a series of normal human heart tissues varying between five and 33 weeks of gestational age, utilizing both enzymatic single immunohistochemistry, as well as double immunofluorescence. We showed here that CD105 is already expressed at five weeks of gestational age in the future endocardium, and that between 9 and 10 weeks it shows clear-cut formed vessels. CD31 was also present diffusely at five weeks in the myocardium, while beginning with seven weeks, endocardium and vessels were clearly positive. Contrary to what it might be expected for striated muscle cells, cardiomyocytes were α-SMA positive between 9 and 20 weeks, a time window during which the marker showed clear-cut sarcomer formation. Desmin was first detected at nine weeks lining the cardiomyocyte plasma membrane, and after 17 weeks it showed the adult-like striated pattern of the protein. As expected, vimentin was already present in the mesenchymal cells from the first investigated time point, retaining a perivascular localization only towards higher ages. This is the first study that describes these vascular, muscular and mesenchymal factors on a large series of sequential human tissues, in an attempt to shed more light on the development of heart.

Reduced cerebral blood flow beyond the compensatory mechanisms leads to cerebral hypoxia. Hypoxia causes various lesions of neurons, glial cells and cerebral blood vessels, depending on its duration and intensity. In our study, we reduced cerebral blood flow in the experience animal on average by 30%, by right internal carotid artery ligation. Fifteen days after the onset of hypoxia, by histology and immunohistochemical studies, we identified neuronal, glial and vascular damage. Lesions of nerve and glial cells ranged from changes of cytoplasmic tinting with the development of "red neurons", to neuronal and glial cytolysis with areas of focal necrosis. Vascular lesions were represented by the collapse, fragmentation and discontinuity of capillaries, always associated with a marked perivascular edema.

Background: We report a case of a 78-year-old woman with a large cerebral infarction probably due to athermanous embolism following atrial fibrillation., Case Description: The patient, known with atrial fibrillation, high blood pressure and heart failure, complained of headache and motor impairment on the left side of the body. CT imaging revealed a subacute ischemic lesion in the right fronto-occipital lobes, and an old ischemic lesion in the right fronto-parietal lobes. Anticoagulant treatment was conducted with careful monitoring of the coagulability status. After almost three weeks, suddenly the patient became comatose and died shortly after. Macroscopic and microscopic examination confirmed the cortico-subcortical ischemic lesions, but also identified a fresh hemorrhagic site in pons, distant from the initial lesion sites. An immunohistochemical study identified blood vessels in the ischemic sites completely isolated from any glial support., Conclusions: This is a rare case of a large cerebral infarction with a pontine hemorrhagic event.

In the past 30 years, after the discovery of vascular proliferation factors, angiogenesis is one of the most intensively studied fields. Restoring the vascular network after burn injury is essential for healing, as it brings oxygen and nutrients to injured tissues, improves the contribution of inflammatory cells and prepares the damaged area for repair and tissue regeneration. To study the process of angiogenesis we used seven groups of five animals, each of adult Wistar rats, which were inflicted with third degree skin burns. From each group of animals, we sampled at successive intervals of three days the entire burnt wound with a ring of surrounding normal skin. Sampled skin fragments were processed for paraffin inclusion, sectioned with a microtome and stained with Hematoxylin-Eosin or Masson trichrome. The samples were also analyzed using single chromogenic immunohistochemistry or double immunofluorescence for the presence of CD34 and alpha smooth muscle actin (α-SMA). Angiogenesis process started at about three days after the burn infliction, with the appearance of tubular structures lined by CD34-positive cells. Subsequently, these cells showed intense proliferative activity that generated a network that included progressive neovascularization around the wound surface. Maximum vascular proliferation occurred at 9-15 days after injury, when the number of capillaries reached 229/mm², and the total area of capillary angiogenesis at 100.27 μm² (about 10% of the section area). Subsequently, the process of angiogenesis was gradually reduced, but remained at moderate levels after wound healing. During the process of angiogenesis, there was a very close relationship between CD34-positive cells and pericytes (as α-SMA-positive).

The varied morphological forms in which astrocytes occur in brain of ischemic/hemorrhagic stroke and Alzheimer's disease (AD) patients are complex and the mechanisms that drive their formation are not yet properly understood. Subjective differences can be described between these pathologies in what it concerns astrocyte implication, but these have not been yet subjected to a morphometrical quantification. Here we apply a fractal dimension (FD) analysis algorithm to differentiate both between fibrous, protoplasmatic and activated astroglia; but also between the three pathological conditions studied. Analyzing more than 1000 astroglia, we show here first that FD can clearly differentiate between the three morphological subtypes. Second, we describe resemblances of the FD values for ischemic and hemorrhagic lesions, and significant differences when these are compared to AD patients. These results are further discussed and integrated in what it regards the preferential regions proved to be affected in these conditions, and which parallels our results. This work illustrates that fractal dimension analysis of astroglia is a useful method for quantitatively describing gliosis in different pathologies, and that it may offer more insight into the pathogenesis of brain diseases.

We study here the histopathological changes in twenty-two cases of acute ischemic stroke. The average age of the patients was 62-year-old, and the interval from the onset of the disease to the death varied from 6 hours to 15 years. The brain lesions after acute stroke were observed in all regions. Their evolution allowed us to classify them in fourth stages. Phase one changes (1-2 days after onset) (n=2 patients) included red hypoxic and "ghost" neurons and other acute neuronal injury and spongiosis. The second phase (n=14 patients) was subdivided into: (a) a phase of acute inflammation (3-37 days after onset) (n=5 patients), where we observed especially features of acute inflammation together with coagulative necrosis, and (b) phase of chronic inflammation (10 days-53 years after the onset) (n=9 patients), in which prevail mononuclear and macrophage infiltrate, astrogliosis, spongiosis and neo-vascularization. In the third phase (26 days-23 years after the onset), we included six cases characterized by the absence of an inflammatory reaction, presence of cavitation, astrogliosis and macrophages. Our study describes the heterogeneity of brain injury after acute ischemic stroke with the participation of all brain components, and the chronology in which these lesions develop and evolve.