Immunohistochemical Expression of Ki-67, Dopamine D1 and Dopamine D2 Receptors in Meningiomas in a Tertiary Institution in Mexico

Objectives Meningiomas (MNGs) are the most common intracranial tumors found in the adult population. While most intracranial MNGs may be surgically removed, a subset of patients remains ineligible for conventional treatment. This is either because of a lack of surgical access or due to atypical, anaplastic or invasive characteristics of the tumors. These patients may benefit from targeted therapies that focus on cell receptor expression. The aim of this study was to assess dopamine receptor (DR) and Ki-67 expression in the MGNs of patients treated with surgery in the Instituto Nacional de Neurología y Neurocirugía, Mexico. Materials and methods This study analyzed 23 patients with confirmed MNG diagnoses (10 female and 13 male (mean age: 44.5 years)) who had undergone surgical resection between 2010 and 2014 at our institution. In the collected samples, we performed analyses for Ki-67, Dopamine 1 and Dopamine 2 receptors' expression. Results For the markers Ki-67, DR-D1 and DR-D2, the mean percentual expressions were 18.9%, 23.02% and 8.33%. No significant correlation was found between the expressions of these receptors and the studied MNG characteristics. The expression index of Ki-67 showed a significant relation with mean age (p = 0.03) and prolactin levels (p = 0.02). Conclusions Samples showed varied expressions of the studied receptors. Despite the difference in expressions between the markers, more studies are needed to confirm the findings. In contrast to previous studies, we could not find any relationship between D2-R and tumor characteristics.

Teratoma With Malignant Ectomesenchymoma in the Pineal Region: A Case Report

Tumors involving the pineal gland include germinomas, non-germinomatous, and parenchymal tumors. Sometimes these tumors can be differentiated into rhabdomyosarcoma, which is an aggressive and rapidly recurring sarcoma but is a rare event. We present the case of a 23-year-old male, with an eight-year-long history of a non-treated brain tumor compatible with a teratoma. Chemotherapy and radiotherapy were offered, and two years later, malignant transformation to astrocytoma, rhabdomyosarcoma, neural cell carcinoma, ganglioglioma, and low-grade chondrosarcoma was noted. Immunohistochemistry was valuable in differentiating these entities that confirmed the diagnosis. Malignant transformations may be secondary to the normal transformation of multipotent embryonic cells into more developed tissues after radiotherapy of teratoma and malignant ectomesenchymoma transformation.

Comparative Proteomic Study Shows the Expression of Hint-1 in Pituitary Adenomas

Pituitary adenomas (PAs) can be unpredictable and aggressive tumors. No reliable markers of their biological behavior have been found. Here, a proteomic analysis was applied to identify proteins in the expression profile between invasive and non-invasive PAs to search for possible biomarkers. A histopathological and immunohistochemical (adenohypophyseal hormones, Ki-67, p53, CD34, VEGF, Flk1 antibodies) analysis was done; a proteomic map was evaluated in 64 out of 128 tumors. There were 107 (84%) invasive and 21 (16%) non-invasive PAs; 80.5% belonged to III and IV grades of the Hardy–Vezina classification. Invasive PAs (n = 56) showed 105 ± 43 spots; 86 ± 32 spots in non-invasive PAs (n = 8) were observed. The 13 most prominent spots were selected and 11 proteins related to neoplastic process in different types of tumors were identified. Hint1 (Histidine triad nucleotide-binding protein 1) high expression in invasive PA was found (11.8 ± 1.4, p = 0.005), especially at high index (>10; p = 0.0002). High Hint1 expression was found in invasive VEGF positive PA (13.8 ± 2.3, p = 0.005) and in Flk1 positive PA (14.04 ± 2.28, p = 0.006). Hint1 is related to human tumorigenesis by its interaction with signaling pathways and transcription factors. It could be related to invasive behavior in PAs. This is the first report on Hint expression in PAs. More analysis is needed to find out the possible role of Hint in these tumors.

Resveratrol reduces cerebral edema through inhibition of de novo SUR1 expression induced after focal ischemia

Cerebral edema is a clinical problem that frequently follows ischemic infarcts. Sulfonylurea receptor 1 (SUR1) is an inducible protein that can form a heteromultimeric complex with aquaporin 4 (AQP4) that mediate the ion/water transport involved in brain tissue swelling. Transcription of the Abcc8 gene coding for SUR1 depends on the activity of transcriptional factor SP1, which is modulated by the cellular redox environment. Since oxidative stress is implicated in the induced neuronal damage in ischemia and edema formation, the present study aimed to evaluate if the antioxidant resveratrol (RSV) prevents the damage by reducing the de novo expression of SUR1 in the ischemic brain. Male Wistar rats were subjected to 2 h of middle cerebral artery occlusion followed by different times of reperfusion. RSV (1.9 mg/kg; i.v.) was administered at the onset of reperfusion. Brain damage and edema formation were recognized by neurological evaluation, time of survival, TTC (2,3,5-Triphenyltetrazolium chloride) staining, Evans blue extravasation, and water content. RSV mechanism of action was studied by SP1 binding activity measured through the Electrophoretic Mobility Shift Assay, and Abcc8 and Aqp4 gene expression evaluated by qPCR, immunofluorescence, and Western blot. We found that RSV reduced the infarct area and cerebral edema, prevented blood-brain barrier damage, improved neurological performance, and increased survival. Additionally, our findings suggest that the antioxidant activity of RSV targeted SP transcription factors and inhibited SUR1 and AQP4 expression. Thus, RSV by decreasing SUR1 expression could contribute to reducing edema formation, constituting a therapeutic alternative for edema reduction in stroke.

Antioxidant Properties and Protective Effects of Some Species of the Annonaceae, Lamiaceae, and Geraniaceae Families against Neuronal Damage Induced by Excitotoxicity and Cerebral Ischemia

This study aimed to compare the antioxidant activities of extracts obtained from three plant families and evaluate their therapeutic effect on strokes. Ethanol extracts were obtained from either the leaf or the aerial parts of plants of the families Annonaceae (Annona cherimola, A. diversifolia, A. muricata, A. purpurea, and A. reticulata), Lamiaceae (Salvia amaríssima and S. polystachya), and Geraniaceae (Geranium niveum and G. mexicanum). Extracts were analyzed in terms of hydroxyl radical (OH•), peroxyl radical (ROO•), and superoxide anion (O2•-). The efficiency of the extracts to prevent neuronal death induced by excitotoxicity was tested with the tetrazolium assay, the O2•- scavenging capacity was evaluated with the dihydroethidium dye, and the protective effect of the extracts with the highest antioxidant activity was tested on a stroke experimental model. The extracts' IC50 values (μg/mL) of scavenging varied from 98.9 to 155.04, 4.5 to 102.4, and 20.2 to 118.97 for OH•, ROO•, and O2•-, respectively. In the excitotoxicity model, Annonaceae extracts were highly cytotoxic while Lamiaceae and Geraniaceae reduced intracellular O2•- production and protect neurons against oxidative stress. Salvia polystachya reduced cerebral damage, as well as improved survival and behavior after ischemia. Our results encouraged the use of plant extracts as natural antioxidants to minimize neuronal injury following stroke.

Aged garlic extract and S-allylcysteine increase the GLUT3 and GCLC expression levels in cerebral ischemia

BACKGROUND

During cerebral ischemia, energy restoration through the regulation of glucose transporters and antioxidant defense mechanisms is essential to maintain cell viability. Antioxidant therapy has been considered effective to attenuate brain damage; moreover, the regulation of transcription factors that positively regulate the expression of glucose transporters is associated with this therapy. Recently, it has been reported that the use of antioxidants such as S-allylcysteine (SAC), a component of aged garlic extract (AGE), improves survival in experimental models of cerebral ischemia.

OBJECTIVES

The aim of this study was to determine the effect of AGE and SAC on the level of mRNA expression of the main neuronal glucose transporter (GLUT3) and the glutamate cysteine ligase catalytic subunit (GCLC) in rats with transient focal cerebral ischemia.

MATERIAL AND METHODS

Cerebral ischemia was induced in male Wistar rats by middle cerebral artery occlusion (MCAO) for 2 h. The animals were sacrificed after different reperfusion times (0-48 h). Animals injected with AGE (360 mg/kg, intraperitoneally (i.p.)) and SAC (300 mg/kg, i.p.) at the beginning of reperfusion were sacrificed after 2 h. The mRNA expression level was analyzed in the fronto-parietal cortex using quantitative polymerase chain reaction (qPCR).

RESULTS

Two major increases in GLUT3 expression at 1 h and 24 h of reperfusion were found. Both treatments increased GLUT3 and GCLC mRNA levels in control and under ischemic/reperfusion injury animals.

CONCLUSIONS

This data suggests that SAC and AGE might induce neuroprotection, while controlling reactive oxygen species (ROS) levels, as indicated by the increase in GCLC expression, and regulating the energy content of the cell by increasing glucose transport mediated by GLUT3.

Resveratrol Activates Neuronal Autophagy Through AMPK in the Ischemic Brain

During cerebral ischemia, oxygen and glucose levels decrease, producing many consequences such as the generation of reactive oxygen species, tissue injury, and the general metabolism collapse. Resveratrol triggers signaling dependent on the protein kinase activated by adenosine monophosphate (AMPK), the sensor of cellular energy metabolism that regulates autophagy, eliminates damaged mitochondria, and increases energy sources. In the present study, we investigated the participation of AMPK activation in the protective effect of resveratrol on cerebral ischemia and excitotoxicity. We found that resveratrol increased the levels of phosphorylated AMPK in the cerebral cortex of rats subjected to middle cerebral artery occlusion (MCAO) and in primary cultured neurons exposed to glutamate-induced excitotoxicity. Resveratrol (1.8 mg/Kg; i. v.; administered at the beginning of reperfusion) decreased the infarct area and increased survival of rats subjected to MCAO. In neuronal cultures, resveratrol treatment (40 μM, after excitotoxicity) reduced the production of superoxide anion, prevented the overload of intracellular Ca⁺² associated to mitochondrial failure, reduced the release of the lactate dehydrogenase enzyme, and reduced death. It also promoted mitophagy (increased Beclin 1 level, favored the recruitment of LC3-II, reduced LAMP1, and reduced mitochondrial matrix protein HSP60 levels). In both models, inhibition of AMPK activation with Compound C obstructed the effect of resveratrol, showing that its protective effect depends, partially, on the activation of the AMPK/autophagy pathway.

Diallyl Trisulfide Protects Rat Brain Tissue against the Damage Induced by Ischemia-Reperfusion through the Nrf2 Pathway

Stroke is a public health problem due to its high mortality and disability rates; despite these, the pharmacological treatments are limited. Oxidative stress plays an important role in cerebral damage in stroke and the activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) confers protection against oxidative stress. Different compounds, such as diallyl trisulfide (DATS), have the ability to activate Nrf2. DATS protects against the damage induced in oxygen-glucose deprivation in neuronal cells; however, in in vivo models of cerebral ischemia, DATS has not been evaluated. Male Wistar rats were subjected to 1 h of ischemia and seven days of reperfusion and the protective effect of DATS was evaluated. DATS administration (IR + DATS) decreased the infarct area and brain damage in the striatum and cortex; improved neurological function; decreased malondialdehyde and metalloproteinase-9 levels; increased Nrf2 activation in the cortex and the expression of superoxide dismutase 1 (SOD1) in the nucleus, SOD2 and glutathione S-transferase (GST) in the striatum and cortex; and increased the activity of catalase (CAT) in the striatum and glutathione peroxidase (GPx) in the cortex. Our results demonstrate the protective effect of DATS in an in vivo model of cerebral ischemia that involves Nrf2 activation.

Three-dimensional Alginate-bead Culture of Human Pituitary Adenoma Cells

A three-dimensional culture method is described in which primary pituitary adenoma cells are grown in alginate beads. Alginate is a polymer derived from brown sea algae. Briefly, the tumor tissue is cut into small pieces and submitted to an enzymatic digestion with collagenase and trypsin. Next, a cell suspension is obtained. The tumor cell suspension is mixed with 1.2% sodium alginate and dropped into a CaCl2 solution, and the alginate/cell suspension is gelled on contact with the CaCl2 to form spherical beads. The cells embedded in the alginate beads are supplied with nutrients provided by the culture media enriched with 20% FBS. Three-dimensional culture in alginate beads maintains the viability of adenoma cells for long periods of time, up to four months. Moreover, the cells can be liberated from the alginate by washing the beads with sodium citrate and seeded on glass coverslips for further immunocytochemical analyses. The use of a cell culture model allows for the fixation and visualization of the actin cytoskeleton with minimal disorganization. In summary, alginate beads provide a reliable culture system for the maintenance of pituitary adenoma cells.

Biotin deprivation impairs mitochondrial structure and function and has implications for inherited metabolic disorders

Certain inborn errors of metabolism result from deficiencies in biotin containing enzymes. These disorders are mimicked by dietary absence or insufficiency of biotin, ATP deficit being a major effect,whose responsible mechanisms have not been thoroughly studied. Here we show that in rats and cultured cells it is the result of reduced TCA cycle flow, partly due to deficient anaplerotic biotin-dependent pyruvate carboxylase. This is accompanied by diminished flow through the electron transport chain, augmented by deficient cytochrome c oxidase (complex IV) activity with decreased cytochromes and reduced oxidative phosphorylation. There was also severe mitochondrial damage accompanied by decrease of mitochondria, associated with toxic levels of propionyl CoA as shown by carnitine supplementation studies, which explains the apparently paradoxical mitochondrial diminution in the face of the energy sensor AMPK activation, known to induce mitochondria biogenesis. This idea was supported by experiments on AMPK knockout mouse embryonic fibroblasts (MEFs). The multifactorial ATP deficit also provides a plausible basis for the cardiomyopathy in patients with propionic acidemia, and other diseases.Additionally, systemic inflammation concomitant to the toxic state might explain our findings of enhanced IL-6, STAT3 and HIF-1α, associated with an increase of mitophagic BNIP3 and PINK proteins, which may further increase mitophagy. Together our results imply core mechanisms of energy deficit in several inherited metabolic disorders.

Intracerebral injection of oil cyst content of human craniopharyngioma (oil machinery fluid) as a toxic model in the rat brain

Craniopharyngiomas (CPs) are benign epithelial cystic tumors of the sellar and suprasellar region with a high survival rate and high recurrence in children. CPs contain dense oily fluid, but little is known yet about this content and its contribution to tissue damage and tumoral growth. In this study, we developed a simple experimental model produced by intracortical injection to rats of the cyst fluid content collected from human CPs to explore its possible contribution to brain tissue damage. The cyst fluid of the CPs ("oil machinery fluid") was collected during surgical removal, briefly preserved and further tested in rats through intracortical infusion. The group receiving "oil machinery fluid" presented increased reactive oxygen species formation, oxidative damage to lipids and reactive gliosis accompanied by augmented immunoreactivity to peroxiredoxin and thioredoxin reductase 1 at 15, 30 and 45 days post-injection. Other markers of inflammation and cell damage were stimulated at all post-lesion days tested. There was also a body weight gain. The persistence of tissue damage and oxidative stress suggests that "oil machinery fluid" exerts progressive alterations similar to those observed in patients with CPs, supporting the concept that some components of cyst fluid may contribute to brain tissue damage in these patients.

Retinoic acid reduces solvent-induced neuropathy and promotes neural regeneration in mice

In humans, exposure to organic solvents (OS) is frequent in work activities or as a recreational inhalant, inducing severe neuropathy (secondary to demyelization of peripheral nerves). We have previously shown that all-trans retinoic acid (ATRA) increases local content of neural growth factor (NGF), improving peripheral neuropathy of diverse origins. In this study, we evaluated the effect of ATRA on OS-induced peripheral neuropathy in experimental mice. Two simultaneous experiments were performed. The first one aimed to evaluate ATRA for the prevention of damage induced by OS, the second to test ATRA as an OS-induced neuropathy treatment. Nociceptive threshold latency and NGF concentration in serum and in peripheral nerves were determined. Morphological changes and evidence of sciatic nerve regeneration were evaluated. Mice exposed to OS developed neuropathy and axonal degeneration. ATRA diminished the effects of OS inhalation on sensorial changes and nerve morphology. Treatment with ATRA reversed sensorial and nerve morphological changes of OS-induced neuropathy, and this was associated with increased contents of NGF. Similar to previous experiences on diabetic and toxic neuropathy, ATRA reduced and partially reversed the peripheral neuropathy caused by OS exposure. These favorable effects apparently are due to local production of NGF induced by neural regeneration in response to the administration of retinoic acid.

[Clinical practice guideline for the diagnosis and treatment of hyperprolactinemia]

BACKGROUND

Hyperprolactinemia is a common finding within clinical practice in both endocrinology and general practice fields, amongst other specialties. The general practitioner and other specialists must know the indications and serum prolactin determination parameters in order to, once detected, derive the patient for a correct assessment and begin treatment.

OBJECTIVE

Formulate a clinical practice guideline evidence-based for the diagnosis and treatment of hyperprolactinemia.

METHOD

It took the participation of eight gynecologists, two pathologists and a pharmacologist in the elaboration of this guideline due their experience and clinical judgement. These recommendations were based upon diagnostic criteria and levels of evidence from treatment guidelines previously established, controlled clinical trials and standardized guides for adolescent and adult population with hyperprolactinemia.

RESULTS

During the conformation of this guideline each specialist reviewed and updated a specific topic and established the evidence existent over different topics according their field of best clinical expertise, being enriched by the opinion of other experts. At the end, all the evidence and decisions taken were unified in the document presented here.

CONCLUSIONS

It is presented the recommendations established by the panel of experts for diagnosis and treatment of patients with high levels of prolactin; also the level of evidence for the diagnosis of hyperprolactinemia, handling drug-induced hyperprolactinemia and prolactinomas in pregnant and non-pregnant patients.

Aged garlic extract attenuates cerebral damage and cyclooxygenase-2 induction after ischemia and reperfusion in rats

Different garlic products reduce the cerebral ischemic damage due to their antioxidant properties. In this work, we investigated the effect of aged garlic extract (AGE) on cyclooxygenase-2 (COX-2) protein levels and activity, and its role as a possible mechanism of neuroprotection in a cerebral ischemia model. Animals were subjected to 1 h of ischemia plus 24 h of reperfusion. AGE (1.2 ml/kg weight, i.p.) was administered at onset of reperfusion. To evaluate the damage induced by cerebral ischemia, the neurological deficit, the infarct area, and the histological alterations were measured. As an oxidative stress marker to deoxyribonucleic acid, 8-hydroxy-2-deoxyguanosine (8-OHdG) levels were determined. Finally, as inflammatory markers, TNFα levels and COX-2 protein levels and activity were measured. AGE treatment diminished the neurological alterations (61.6%), the infarct area (54.8%) and the histological damage (37.7%) induced by cerebral ischemia. AGE administration attenuated the increase in 8-OHdG levels (77.8%), in TNFα levels (76.6%), and in COX-2 protein levels (73.6%) and activity (30.7%) induced after 1 h of ischemia plus 24 h of reperfusion. These data suggest that the neuroprotective effect of AGE is associated not only to its antioxidant properties, but also with its capacity to diminish the increase in TNFα levels and COX-2 protein expression and activity. AGE may have the potential to attenuate the cerebral ischemia-induced inflammation.

Retinoic acid reduces chemotherapy-induced neuropathy in an animal model and patients with lung cancer

OBJECTIVE

To evaluate the effect of all-trans retinoic acid (ATRA) as treatment for chemotherapy-induced peripheral neuropathy in an experimental animal model and in a randomized, double-blinded, controlled trial in patients with non-small-cell lung cancer (NSCLC).

METHODS

Forty male Wistar rats were randomized in 5 groups: group A, control; groups B and C, treated with cisplatin; and groups D and E, treated with paclitaxel. ATRA (20 mg/kg PO) was administered for 15 days in groups C and E. We evaluated neuropathy and nerve regeneration-related morphologic changes in sciatic nerve, the concentration of nerve growth factor (NGF), and retinoic acid receptor (RAR)-α and RAR-β expression. In addition, 95 patients with NSCLC under chemotherapy treatment were randomized to either ATRA (20 mg/m(2)/d) or placebo. Serum NGF, neurophysiologic tests, and clinical neurotoxicity were assessed.

RESULTS

The experimental animals developed neuropathy and axonal degeneration, associated with decreased NGF levels in peripheral nerves. Treatment with ATRA reversed sensorial changes and nerve morphology; this was associated with increased NGF levels and RAR-β expression. Patients treated with chemotherapy had clinical neuropathy and axonal loss assessed by neurophysiology, which was related to decreased NGF levels. ATRA reduced axonal degeneration demonstrated by nerve conduction velocity and clinical manifestations of neuropathy grades ≥2.

CONCLUSIONS

ATRA reduced chemotherapy-induced experimental neuropathy, increased NGF levels, and induced RAR-β expression in nerve. In patients, reduction of NGF in serum was associated with the severity of neuropathy; ATRA treatment reduced the electrophysiologic alterations.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that ATRA improves nerve conduction in patients with chemotherapy-induced peripheral neuropathy.

Epithelial cell adhesion molecule expression in pituitary adenomas: an immunohistochemical study

An important amount of data correlating the expression of epithelial cell adhesion molecule (Ep-CAM) with cellular proliferation and de-differentiation could directly contribute to carcinogenesis. The aim of this study is to evaluate prognosis relevance of Ep-CAM expression in a group of pituitary adenomas. Epithelial cell adhesion molecule, proliferating cell nuclear antigen, and microvascular density labeling indices in pituitary adenomas were determined by immunohistochemistry on tissue samples obtained from each adenoma after surgery. We evaluated 45 adenomas. Sixty-two percent were nonsecretor adenomas and 37.8% were secretor tumors. Immunohistochemistry was scored for immunoexpression of Ep-CAM (cytoplasmic, membrane, and mixed pattern). Proliferating cell nuclear antigen and vascular density (CD34) labeling indices were assessed. Statistical significance was observed between Ep-CAM cytoplasmic immunoreactions (P = .000) and higher proliferating cell nuclear antigen (P = .001) in secretor adenomas compared with nonsecretor tumors. Vascular density labeling indices did not show statistical significance. Therefore, Ep-CAM could be evaluated to distinguish secretor and nonsecretor pituitary adenomas. These suggest that the markers could predict the growth potential of individual pituitary adenomas.

Aged garlic extract delays the appearance of infarct area in a cerebral ischemia model, an effect likely conditioned by the cellular antioxidant systems

Experimental evidence has shown that some garlic-derived products have a protective effect against ischemic brain injury. The present study was designed to investigate the effect of aged garlic extract (AGE), establish the therapeutic window, and determine its protective mechanism in a cerebral ischemia model. Animals were subjected to middle cerebral artery occlusion (MCAO) for 2h and treated with 1.2ml/kg body wt.(i.p.) of AGE 30min before, at the beginning of (0R), or 1h after reperfusion. The 0R treatment significantly reduced the size of the infarct area after 2h of reperfusion. Repeated doses subsequent to the 0R treatment (at 1, 2, or 3h after reperfusion) had no effect on the temporal window of protection. The protective 0R treatment with AGE prevented the increase in nitrotyrosine and the decrease in total superoxide dismutase, glutathione peroxidase, and extracellular superoxide dismutase activities induced by MCAO. These data indicate that AGE delays the effects of ischemia/reperfusion-induced neuronal injury. However, this treatment itself was not associated with a noticeable improvement in the neurological outcome, or with an effect on the inflammatory response. We conclude that the neuroprotective effect of AGE in the 0R treatment might be associated with control of the free-radical burst induced by reperfusion, preservation of antioxidant enzyme activity, and the delay of other pathophysiological processes.

Solid-phase assay for the detection of varicella zoster virus

Aims: ViriChip™ is a novel bionanotechnologic resource that couples atomic-force microscopy with the high-affinity solid-phase capture of viral particles. In this work, it was used for the detection of the varicella zoster virus (VZV). Materials & methods: ViriChip was used for VZV detection. PCR, quantitative real-time PCR and electron microscopy were also used to determine the sensitivity and effectiveness of the method. Results: VZV binding was found to be linear at concentrations between 102 and 105 viral particles/µl of an applied sample and the virus was identified by its distinct morphology, shape and size uniformity. The identity of the VZV was verified by direct visualization using electron microscopy, fluorescent imaging with labeled VZV antibodies, PCR and quantitative PCR. Immunocapture was antibody specific, with a sensitivity of 102 viral particles/µl. Conclusion: The ViriChip method allows the detection and visualization of VZV, as well as the recovery of viral particles without inducing morphological damage, constituting a new and promising tool in the field of virology for the quick and precise detection of a clinically important virus.

Antioxidant, antiinflammatory and antiapoptotic effects of dapsone in a model of brain ischemia/reperfusion in rats

Although dapsone (4,4'-diaminodiphenylsulfone) has been described as a neuroprotective agent in occlusive focal ischemia in rats, its mechanism of action is still unknown. To explore this mechanism, oxidative, inflammatory and apoptotic processes were evaluated in the striatum of adult rats using a model of ischemia-reperfusion (I/R), either with or without dapsone treatment. Male Wistar rats were submitted to transient middle cerebral artery occlusion for 2 hr, followed by reperfusion. Rats were dosed either with dapsone (12.5 mg/kg i.p.) or vehicle 30 min before or 30 min after the ischemia onset. Lipid peroxidation (LP) and nitrotyrosine contents were measured 22 hr after reperfusion, and myeloperoxidase activity was evaluated 46 hr after I/R. Different markers for apoptosis and necrosis were also evaluated both at 24 and 72 hr after I/R experimental procedure. LP increased by 37% in ischemic animals vs controls, and this effect was reversed by dapsone treatments. A similar effect was observed regarding nitrotyrosine striatal contents. Myeloperoxidase activity, a marker of inflammatory response, increased 3.7-fold in ischemic animals vs. control rats, and dapsone treatment antagonized that effect. Although apoptosis was increased by the effect of ischemia at both evaluation times, dapsone antagonized that effect only at 72 hr after surgery. Dapsone antagonized all of the I/R end points measured, showing a remarkable ability to decrease markers of damage through antioxidant, antiinflammatory, and anti-apoptotic effects.

Rhabdoid choroid plexus carcinoma: a rare histological type

Primary central nervous system atypical teratoid/rhabdoid tumors mostly occur during early childhood and are almost invariably fatal. These tumors show similar histological and radiological features to primitive neuroectodermal tumor, meduloblastoma and choroid plexus carcinoma, but present different biological behaviors. We present the case of an 18 year-old man who presented headache, vomiting and ataxia. CT-scan and MRI revealed a posterior fossa tumor. A gross total resection was performed. An intraoperative study showed papillary-like tumors with large cells and mitotic features. Histological examination showed two different main growth patterns: solid sheets of undifferentiated polygonal cells with papillary features and rhabdoid cells. Immunohistochemically, these rhabdoid cells were positive for vimentin, epithelial membrane antigen, smooth-muscle actin, cytokeratin, S-100 protein, and glial fibrillary acidic protein. Electro-microscopically, the typical rhabdoid cells contained whorled bundles of intermediate filaments in their cytoplasm. A rhabdoid tumor is a clinicalpathological entity and emphasizes the necessity to distinguish this unique tumor from other pediatric central nervous system neoplasms. Cytopathological features, immunohistochemistry and electro-microscopy differential diagnoses are discussed.

Study of the telomerase hTERT fraction, PCNA and CD34 expression on pituitary adenomas. Association with clinical and demographic characteristics

To determine the frequency of human telomerase reverse transcriptase (hTERT) catalytic fraction expression and its association with clinical and demographic characteristics of the patient, as well as with the expression of CD34 and proliferating cell nuclear antigen (PCNA) indexes on adenohypophyseal hormone tissues. A transverse study was realized with 49 cases of hypophyseal adenoma with analysis type cases and controls. The different adenohypophyseal hormones [prolactin (PRL), growth hormone (GH), follicle stimulating hormone, luteinizing hormone, thyroid gland stimulant hormone, adrenocorticotropic hormone (ACTH)], the catalytic fraction of the telomerase hTERT, the PCNA index and the CD34 density were determined by means of immunohistochemical techniques. The clinical, demographic and histopathological characteristics of the patients with and without hTERT expression were compared by means of Pearson's Chi-squared, Fisher's exact test and Mann-Whitney's U. Twenty-eight point six percent of the adenomas had positive expression for hTERT. The variables significantly correlated with hTERT's expression were younger age of presentation, diagnostic of adenoma producer, higher PCNA index, higher CD34 density, increased GH on serum and the expression on PRL tissue, GH and ACTH. Tobacco history had a negative association with hTERT's expression. The telomerase could be a marker of cellular proliferation associated with angiogenesis and hormonal activity. Evaluation of these variables could provide information about their biological behavior.

Efficacy of nitazoxanide, tizoxanide and tizoxanide/albendazole sulphoxide combination against Taenia crassiceps cysts

OBJECTIVES

Neurocysticercosis is a common parasitic disease in the CNS in humans caused by the metacestode Taenia solium, with high incidence in developing countries. Albendazole is the drug of choice. However, a wide interindividual variability in the response has been reported. In order to evaluate alternative treatment options, the in vitro efficacy of nitazoxanide, its main metabolite tizoxanide as well as the tizoxanide and albendazole sulphoxide combination was tested against Taenia crassiceps cysts.

METHODS

T. crassiceps cysts were incubated in culture medium containing different concentrations of nitazoxanide, tizoxanide and albendazole sulphoxide (0.037-0.42 microg/mL). The effect of the tizoxanide and albendazole sulphoxide combination was evaluated in a fixed-concentration ratio (1:1). Isobolographic analyses were used to define the kind of interaction between drugs. Morphological and ultrastructural alterations over the parasite tissue were observed by light and transmission electron microscopy.

RESULTS

Nitazoxanide and tizoxanide exhibited cestocidal activity which was time-concentration-dependent. The EC(50) values were 0.15, 0.12 and 0.080 microg/mL for nitazoxanide, tizoxanide and albendazole sulphoxide, respectively. No statistical differences between EC(50) values were found, indicating that nitazoxanide and tizoxanide are equally potent as albendazole sulphoxide. The effect of the tizoxanide and albendazole sulphoxide combination was faster than that observed with each drug alone. Isobolographic analysis showed that the effect of the combination was additive. Nitazoxanide and tizoxanide had an effect on the germinal layer, where lipid droplets were found. Nitazoxanide and tizoxanide produced less damage than albendazole sulphoxide on the germinal layer. After the tizoxanide and albendazole sulphoxide combination, a high accumulation of lipid droplets within the germinal layer of the parasite was found.

CONCLUSIONS

Our results suggest that nitazoxanide in combination with albendazole could be useful for treatment of cysticercosis infections. Additional in vivo studies are required to confirm this hypothesis.

Late development of intraventricular papillary pituitary carcinoma after irradiation of prolactinoma

BACKGROUND

Intracranial dissemination of pituitary adenomas is a rare event that does not equate malignancy. Most of the cases have been reported as metastases from pituitary carcinoma. A case of papillary pituitary carcinoma developed 12 years after radiotherapy for prolactin-secreting hormone pituitary adenoma is presented.

CASE DESCRIPTION

A 37-year-old woman was admitted for the second time with neurologic disturbance and hypertension. A gadolinium-enhanced magnetic resonance scan of the brain demonstrated a 50-mm enhanced mass (absent on previous studies) on the lateral ventricle, involving the left temporal lobe. The patient underwent a craniotomy and biopsy of the lesion that was consistent with pituitary carcinoma; it was immunoreactive to follicle-stimulating hormone, adrenocorticotropic hormone, pituitary tumor-transforming gene, and epithelial cell adhesion molecule. Transmission electron microscopy analysis confirmed the secretory pituitary tumor diagnosis.

CONCLUSIONS

The tumor was considered a primary pituitary papillary carcinoma. The clinical course indicated that this tumor was the seedling of a pituitary tumor, although it could be interpreted as metastases from a pituitary carcinoma.

EGP-314 is expressed differentially in three brain zones at an early time in an experimentally induced ischemia rat model

Gene expression in frontal, occipital, and hippocampal regions of rat brains at 15 min of ischemic injury was studied in a rat model by producing focal cerebral ischemia through middle cerebral artery (MCA) occlusion without reperfusion. Catalase, epithelial glycoprotein (EGP-314), cytochrome C oxidase-subunit 1, ribosomal L31 protein, and ceruloplasmin were found to be differentially expressed. Specific primers were designed to study this newly reported brain EGP-314, a cellular adhesion molecule involved in cell-cell and cell-extracellular matrix interactions and related with cytoskeletal organization, differentiation, and proliferation. In the frontal and occipital lobes, EGP-314 expression was low in control and ischemic conditions and increased in sham injured conditions, whereas in the hippocampal region its expression was induced only by ischemia. In situ hybridization and immunohistochemistry revealed that EGP-314 mRNA and the protein were present in the ischemic hippocampus pyramidal neurons. DNA fragmentation was demonstrated by TUNEL and LM-PCR analysis in hippocampus region. TUNEL positive pyramidal neurons were observed at 15 min of ischemia. DNA ladder was found at 12 and 15 min of ischemia.

Lenticular acral keratosis in washerwomen

BACKGROUND

In 1952, a Brazilian dermatologist, Oswaldo Costa, described a dermatosis characterized by accentuation of the cutaneous folds on the knuckles of both hands and small horny papules on the thenar eminences, posterior surface of the wrists, and the interdigital space between thumb and index finger; he called this entity acrokeratoelastoidosis. Other similar entities, such as focal acral hyperkeratosis and marginal keratoelastoidosis, have been described. The features of the different types of lenticular acral keratosis are discussed.

MATERIALS AND METHODS

Fifteen patients with lenticular acral keratosis and five controls were studied clinically and pathologically. The skin biopsies were processed for light and transmission electron microscopy. The clinical data were reviewed, and the following variables were recorded: age, sex, distribution and morphology of the lesions, history of exposure to sunlight and objective evidence of photodamage, familial incidence, occupation and hobbies, time of evolution, and response to previous treatments. The results were compared with samples taken at autopsy from five women without dermatoses.

RESULTS

All patients were women, with flat, keratotic papules located on the transition between the dorsal and volar surfaces of the fingers and hands. Histologically, there was an increased amount of elastic fibers, which were coarse and tortuous, and appeared to be interrupted in some areas. In contrast, there were sparse, thin fibers in the mid and deep dermis in the skin of controls. Transmission electron microscopy of these papules showed enlarged, thickened elastic fibers, with deposits of electron-dense, coarse clumps.

CONCLUSIONS

Our cases do not seem to correspond to any of the three entities which are manifested clinically by acral keratotic plaques. All of these women washed clothes by hand on a stone washboard for many hours every day. As there is no clinical or histologic evidence of actinic damage, chronic trauma seems to be the cause of the dermatosis in this type of patient. We propose the term "occupational lenticular acral keratosis" for our cases.

Ultrastructural changes in limb distal nerves of rats with alcoholism and/or malnutrition before and after dietary correction

To study peripheral nerves changes in chronic alcoholism and in malnutrition, we examined ultrastructurally the distal nerve branches of the digits of rats treated with four different dietary schemes, as follows: controls (n = 22), fed standard rodent diet plus water ad libitum; alcoholism (n = 12), fed the standard diet and 2-12% ethanol in drinking water; malnutrition (n = 21), fed with corn tortillas instead of standard diet; and alcoholism and malnutrition combined (n = 22). After 10 months under these conditions, a proportion of animals from each group were sacrificed. The remaining rats of the malnutrition and alcoholism alone groups were deferred a standard diet. The combined alcohol + malnutrition group was subdivided into standard diet, malnutrition and ethanol. After a further 4 months under these new conditions, the animals were sacrificed. Ultrastructural examination of limb distal nerve branches showed that glycogen-like particles were more common in malnourished animals, whereas remyelinating axons were more numerous in ethanol-treated rats. Bands of regeneration were present in both groups, but were more common in animals treated with ethanol. These features decreased significantly when the respective nutritional factor was reversed. The results confirm that ethanol plays a definitive role in the development of alcoholic neuropathy and that malnutrition accentuates, the histopathological abnormalities.