Administering crocin ameliorates anxiety-like behaviours and reduces the inflammatory response in amyloid-beta induced neurotoxicity in rat.

Anxiety, hippocampus synaptic plasticity deficit, as well as pro-inflammatory cytokines, are involved in Alzheimer's disease (AD). The present study is designed to evaluate the possible therapeutic effect of crocin on anxiety-like behaviours, hippocampal synaptic plasticity and neuronal shape, as well as pro-inflammatory cytokines in the hippocampus using in vivo amyloid-beta (Aß) models of AD. The Aß peptide (1-42) was bilaterally injected into the frontal-cortex. Five hours after the surgery, the rats were given intraperitoneal (IP) crocin (30 mg/kg) daily up to 12 days. Elevated plus maze results showed that crocin treatment after bilateral Aß injection significantly increased the percentage of spent time into open arms, frequency of entries, and percentage of entries into open arms as compared with the Aß group. In the open field test, the Aß+crocin group showed a higher percentage of spent time in the centre and frequency of entries into central zone as compare with the Aß treated animals. Administering crocin increased the number of soma, dendrites and axonal arbores in the CA1 neurons among the rats with Aß neurotoxicity. Cresyl violet (CV) staining showed that crocin increased the number of CV-positive cells in the CA1 region of the hippocampus compared with the Aß group. Silver-nitrate staining indicated that crocin reduced neurofibrillary tangle formation induced by Aß. Crocin treatment attenuated the expression of TNF-α and IL-1ß mRNA in the hippocampus compared with the Aß group. Our results suggest that crocin attenuated Aß-induced anxiety-like behaviours and neuronal damage, and synaptic plasticity loss in hippocampal CA1 neurons may via its anti-inflammatory effects.

Cresyl violet as a new contrast agent in probe-based confocal laser endomicroscopy for in vivo diagnosis of gastric intestinal metaplasia.

BACKGROUND AND AIM: Cresyl violet (CV) is a topical dye that allows simultaneous chromoendoscopy and in vivo confocal laser endomicroscopy in identification of neoplastic changes of the lower gastrointestinal tract without intravenous injection of fluorescein, but as yet no investigation has reported its application in the diagnosis of gastric intestinal metaplasia (GIM). This study aims to assess the feasibility as well as diagnosis accuracy of topical CV for in vivo diagnosis of GIM by using probe-based confocal laser endomicroscopy (pCLE). METHODS: In this prospective, open-label, feasibility study, 129 confocal videos from 22 patients with known GIM were analyzed and compared with corresponding histological images to establish the CV staining characteristics. In addition, 47 patients with known or suspected GIM were prospectively enrolled to evaluate the accuracy of this topical CV endomicroscopic imaging. RESULTS: Probe-based confocal laser endomicroscopy with topical CV enabled clear visualization of the goblet cells, absorptive cells, and intestinal villi of GIM. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of pCLE diagnosis of GIM on a per-location analysis was 93.01%, 91.95%, 93.51%, 86.96%, and 96.11%, respectively. The intraclass correlation coefficient for inter-observer agreement and mean kappa value for intra-observer agreement for the diagnosis of GIM was 0.82 and 0.87, respectively. CONCLUSIONS: Topical CV enables real-time chromoendoscopy in conjunction with pCLE examination of the stomach and warrants accurate diagnosis of GIM. It may be an acceptable and potentially alternative dye for confocal imaging in the future.

Cresyl violet: a superior fluorescent lysosomal marker.

We have characterized cresyl violet as a membrane-permeant fluorophore that localizes to lysosomes and acidic vacuoles of budding yeast, Drosophila, human, murine and canine cells. An acidotropic weak base, cresyl violet is shown to be virtually insensitive to physiological alkali and divalent cations. Because of its unique spectral properties, it can be used in combination with green, red and far-red fluorophores, is less susceptible to photobleaching than alternative acidotropic probes, and does not undergo photoconversion. At concentrations that yield bright labeling of acidic compartments, cresyl violet does not alter the organellar pH nor does it affect the buffering capacity. Its affordability, together with its chemical and spectral properties, make cresyl violet a superior lysosomal marker devoid of many of the negative characteristics associated with other lysosomal probes.

[Diagnosis of Helicobacter pylori infection on gastric biopsies: Standard stain, special stain or immunohistochemistry?] / Diagnostic d'infection à Helicobacter pylori sur biopsies gastriques : coloration standard, coloration spéciale ou immunohistochimie ?

INTRODUCTION: There is no consensus on the benefit of performing a systematic complementary technique for the diagnosis of Helicobacter pylori infection. In our laboratory, a cresyl violet was carried out systematically until July 2014; since that date, a cresyl violet or immunohistochemistry is only made on request. We evaluated the value of cresyl violet staining of gastric biopsies to diagnose H. pylori infection by comparing a period of systematic staining to a time when it was made on demand. MATERIAL AND METHODS: We retrospectively studied the gastric biopsy of 786 consecutive patients from April to November 2014, taken in the absence of focal endoscopic lesion. During the first period, hematoxylin-eosin and cresyl violet were performed on all biopsies. During the second period, hematoxylin-eosin was performed and then, if necessary, cresyl violet or immunohistochemistry. All hematoxylin-eosin stained slides were revised to identify H. pylori. We performed immunohistochemistry in cases of active chronic gastritis without H. pylori identified on hematoxylin-eosin or cresyl violet. RESULTS: We have shown that gastric biopsy performed in the absence of focal mucosal lesion are normal in 55% of cases. The percentage of H. pylori infection was similar in both groups. In cases of active chronic gastritis, H. pylori infection is visible, in most cases, on hematoxylin-eosin (94%). Immunohistochemistry should be prescribed only in case of chronic active gastritis without H. pylori identified on standard staining, with bacteria rare or atypically located. CONCLUSION: In our experiment, H. pylori is present only in case of active gastritis (33% of the biopsies in our series) and being almost always identifiable on the standard staining with H-E (in 94% of the cases), it is not It is not necessary to systematically perform, on all gastric biopsies, a complementary histo- or immunohistochemical technique.

The monoamine oxidase inhibition properties of selected structural analogues of methylene blue.

The thionine dye, methylene blue (MB), is a potent inhibitor of monoamine oxidase (MAO) A, a property that may, at least in part, mediate its antidepressant effects in humans and animals. The central inhibition of MAO-A by MB has also been linked to serotonin toxicity (ST) which may arise when MB is used in combination with serotonergic drugs. Structural analogues and the principal metabolite of MB, azure B, have also been reported to inhibit the MAO enzymes, with all compounds exhibiting specificity for the MAO-A isoform. To expand on the structure-activity relationships (SARs) of MAO inhibition by MB analogues, the present study investigates the human MAO inhibition properties of five MB analogues: neutral red, Nile blue, new methylene blue, cresyl violet and 1,9-dimethyl methylene blue. Similar to MB, these analogues also are specific MAO-A inhibitors with cresyl violet (IC50=0.0037µM), Nile blue (IC50=0.0077µM) and 1,9-dimethyl methylene blue (IC50=0.018µM) exhibiting higher potency inhibition compared to MB (IC50=0.07µM). Nile blue also represents a potent MAO-B inhibitor with an IC50 value of 0.012µM. From the results it may be concluded that non-thionine MB analogues (e.g. cresyl violet and Nile blue) also may exhibit potent MAO inhibition, a property which should be considered when using these compounds in pharmacological studies. Benzophenoxazines such as cresyl violet and Nile blue are, similar to phenothiazines (e.g. MB), representative of high potency MAO-A inhibitors with a potential risk of ST.

Cresyl Violet Stains Mast Cells Selectively: Its Application to Counterstaining in Immunohistochemistry.

The thiazine dye toluidine blue (TB) is well known to stain mast cells and hyaline cartilage metachromatically, and thus is mostly often used for their identification. However, TB is not suitable for counterstaining in immunohistochemistry, because of its high-background staining in the cytoplasm of other cell species and in extracellular structures. To expand the knowledge about dyestuffs staining mast cells in consideration with their usage in immunohistochemistry, we determined the stainability of several thiazines and oxazines, which are structurally related compounds to TB, using sections of mast cell-containing tissues. We found that all azine dyes used metachromatically stained mast cells and cartilage. Among these dyes, an oxazines cresyl violet (CV) stained mast cells with lower background, suggesting that those are useful for detecting mast cells and for counterstaining in immunohistochemistry. To ascertain its utility, CV was used in immunostaining of bHSDs in sections from adult rat ovary. Immunopositive signals reflected by DAB development in brown were clearly detected even after CV staining. We conclude that, similar to thiazines, oxazines stain mast cells metachromatically, and that of these, CV is more useful as a counterstain in immunohistochemistry than TB.

Effect of tualang honey against KA-induced oxidative stress and neurodegeneration in the cortex of rats.

BACKGROUND: Administration of KA on rodents has resulted in seizures, behavioral changes, oxidative stress, and neuronal degeneration on selective population of neurons in the brain. The present study was undertaken to investigate the extent of neuroprotective effect conferred by Malaysian Tualang Honey (TH), an antioxidant agent, in the cerebral cortex of rats against KA-induced oxidative stress and neurodegeneration in an animal model of KA-induced excitotoxicity. METHODS: Male Sprague-Dawley rats were randomly divided into five groups: Control, KA-treated group, TH + KA-treated group, aspirin (ASP; anti-inflammatory agent) + KA-treated group and topiramate (TPM; antiepileptic agent) + KA-treated group. The animals were pretreated orally with drinking water, TH (1.0g/kg BW), ASP (7.5mg/kg BW) or TPM (40mg/kg BW), respectively, five times at 12 h intervals. KA (15mg/kg BW) was injected subcutaneously 30 min after last treatment to all groups except the control group (normal saline). Behavioral change was observed using an open field test (OFT) to assess the locomotor activity of the animals. Animals were sacrificed after 2 h, 24 h and 48 h of KA administration. RESULTS: KA significantly inflicted more neuronal degeneration in the piriform cortex and heightened the predilection to seizures as compared with the control animals. Pretreatment with TH reduced the KA-induced neuronal degeneration in the piriform cortex but failed to prevent the occurrence of KA-induced seizures. In the OFT, KA-induced animals showed an increased in locomotor activity and hyperactivity and these were attenuated by TH pretreatment. Furthermore, TH pretreatment significantly attenuated an increase of thiobarbituric acid reactive substances level and a decrease of total antioxidant status level enhanced by KA in the cerebral cortex. CONCLUSION: These results suggest that pretreatment with TH has a therapeutic potential against KA-induced oxidative stress and neurodegeneration through its antioxidant effect.

Construction of a highly sensitive detection platform for heparin based on a "turn-off" cationic fluorescent dye.

A highly sensitive detection platform for heparin was constructed via the utilization of a commercially available cationic fluorescent dye (cresyl violet acetate, CV) as a fluorescence probe. The electrostatic binding between CV and heparin quenched the fluorescence in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic (HEPES) buffer solution (10 mM, pH 7.1). CV was highly selective towards heparin over other potential inferring substances. The detection limit of heparin detection was 5.19 ng/mL, and the linear working range was 0 ∼ 1 µg/mL in HEPES solution. In 1 % serum, the detection platform based on the fluorescence "turn-off" behavior of CV was also successfully constructed with a detection limit of 5.86 ng/mL in the linear range of 0 ∼ 0.8 µg/mL. Moreover, the CV-heparin complex was considered a potential sensor platform for the detection of protamine because of its stronger affinity for heparin and protamine.

Use of Two Novel Dyes to Enhance Visualization of Cut Ends of the Vessel in Microvascular Anastomosis-An Experimental Study of 45 Rats.

BACKGROUND: Good visualization is a prerequisite for performing microvascular anastomosis. The most commonly used dye, methylene blue, has several limitations: it is washed off quickly and stains all the vessel layers. The objective of our study is to use 2 new novel dyes for improving visualization. METHODS: After ethical committee approval, 2 Dyes (2% cresyl violet, 1% eosin) were studied in 3 groups, 20 rats in each group and 5 rats in the combined group. End-to-side anastomosis was performed in the classic fashion in 45 rats. After venotomy, the dye was applied to the raw surface of the vessels and subsequently, anastomosis was performed. The improvement in visualization was judged by 3 blinded experts and nonexperts in 4 groups on a scale of 1-10. Scores were statistically analyzed. After 2 weeks, animals were re-explored to check the delayed patency, and segments were harvested for histopathologic analysis. RESULTS: The immediate and delayed patency rates were 100% (45/45) and 97% (33/34), respectively. In statistical analysis, the combined group (P = 0.005)was judged statistically significant because of the contrast in color. All the layers were stained by both dyes, staining lasted until the end of the surgery. Visibility of the cut ends was better in cresyl violet. All histopathologic findings suggested normal changes at the anastomotic site. CONCLUSIONS: This study showed that the use of these 2 dyes was not only feasible but highly efficacious. Even though all the layers were stained by both the dyes, the visibility of the cut ends was better. In both dyes, staining lasted until the end of surgery. To the best of our knowledge, this is the first study that has used these 2 novel dyes to improve visualization in microvascular anastomosis in an experimental setting.

An effective approach to develop targetable and responsive fluorescent probes for imaging of organelles based on cresyl violet scaffold.

Fluorescent probes combined with confocal microscopy are recognized as a powerful tool for imaging living cells and even organelles due to their high sensitivity and resolution. However, many of analyte-activatable and organelle-targetable fluorescent probes are developed via tedious attempts, and a relatively predictable method to design such probes is still lacking. Herein, we put forward an effective synthetic strategy to construct both targetable and responsive probes for organelles based on the cresyl violet scaffold. The approach allows access to a variety of organelle-targeting fluorescent probes for an analyte of interest via introducing the corresponding targeting and recognition groups to the 5- and 9-positions of cresyl violet, respectively. The potency of the approach is exemplified by its application to develop four cresyl violet-based fluorophores with different organelle-targeting groups, and a mitochondrion-targeting ratiometric probe capable of imaging Pd0 in living cells.

Neuroprotective effects of Korean White ginseng and Red ginseng in an ischemic stroke mouse model.

Background: Stroke is a neurological disorder characterized by brain tissue damage following a decrease in oxygen supply to brain due to blocked blood vessels. Reportedly, 80% of all stroke cases are classified as cerebral infarction, and the incidence rate of this condition increases with age. Herein, we compared the efficacies of Korean White ginseng (WG) and Korean Red Ginseng (RG) extracts (WGex and RGex, respectively) in an ischemic stroke mouse model and confirmed the underlying mechanisms of action. Methods: Mice were orally administered WGex or RGex 1 h before middle cerebral artery occlusion (MCAO), for 2 h; the size of the infarct area was measured 24 h after MCAO induction. Then, the neurological deficit score was evaluated and the efficacies of the two extracts were compared. Finally, their mechanisms of action were confirmed with tissue staining and protein quantification. Results: In the MCAO-induced ischemic stroke mouse model, WGex and RGex showed neuroprotective effects in the cortical region, with RGex demonstrating superior efficacy than WGex. Ginsenoside Rg1, a representative indicator substance, was not involved in mediating the effects of WGex and RGex. Conclusion: WGex and RGex could alleviate the brain injury caused by ischemia/reperfusion, with RGex showing a more potent effect. At 1,000 mg/kg body weight, only RGex reduced cerebral infarction and edema, and both anti-inflammatory and anti-apoptotic pathways were involved in mediating these effects.

Multiscale imaging of the rat brain using an integrated diceCT and histology workflow.

Advancements in tissue visualization techniques have spurred significant gains in the biomedical sciences by enabling researchers to integrate their datasets across anatomical scales. Of particular import are techniques that enable the interpolation of multiple hierarchical scales in samples taken from the same individuals. In this study, we demonstrate that two-dimensional histology techniques can be employed on neural tissues following three-dimensional diffusible iodine-based contrast-enhanced computed tomography (diceCT) without causing tissue degradation. This represents the first step toward a multiscale pipeline for brain visualization. We studied brains from adolescent male Sprague-Dawley rats, comparing experimental (diceCT-stained then de-stained) to control (without diceCT) brains to examine neural tissues for immunolabeling integrity, compare somata sizes, and distinguish neurons from glial cells within the telencephalon and diencephalon. We hypothesized that if experimental and control samples do not differ significantly in morphological cell analysis, then brain tissues are robust to the chemical, temperature, and radiation environments required for these multiple, successive imaging protocols. Visualizations for experimental brains were first captured via micro-computed tomography scanning of isolated, iodine-infused specimens. Samples were then cleared of iodine, serially sectioned, and prepared again using immunofluorescent, fluorescent, and cresyl violet labeling, followed by imaging with confocal and light microscopy, respectively. Our results show that many neural targets are resilient to diceCT imaging and compatible with downstream histological staining as part of a low-cost, multiscale brain imaging pipeline.

Labeling Acidic Compartments of Neutrophils with Cresyl Violet.

We introduce the acidotropic marker cresyl violet to stain acidic granules in live neutrophils. Cresyl violet is less phototoxic, more photostable, and more cost-effective than other commercially available acidotropic markers. Additionally, it does not photoconvert to fluorescent species of a different color, a limitation of other commonly used acidotropic markers. Staining can be readily detected by fluorescence microscopy or by flow cytometry, and can be used as a readout of degranulation in activated neutrophils.

Computational Study of Cresyl Violet Covalently Attached to the Silane Coupling Agents: Application to TiO2-Based Photocatalysts and Dye-Sensitized Solar Cells.

The covalent attachment of photosensitizing dyes to TiO2 using silane coupling agents (SCAs) is a promising strategy for enhancing the photocatalytic activity of TiO2-based photocatalysts and the photovoltaic conversion of dye-sensitized solar cells (DSSCs). This approach can control the geometry and orientation of the photosensitizing dye on the TiO2 surface. In this study, a density functional theory (DFT) and time-dependent DFT (TD-DFT) investigation was carried out on cresyl violet (CV) covalently attached to SCAs with a terminal oxirane group (OTES-Cn) to reveal the influence of OTES-Cn on the geometry of the photosensitizing dyes. The potential of CV covalently attached to OTES-Cn (CV-OTES-Cn) to act as a photosensitizing dye was also analyzed. The hydroxyl group formed by the epoxy-opening reaction between CV and OTES-Cn strongly influenced the geometry of CV-OTES-Cn, which was attributed to a CH-O interaction. Additionally, TD-DFT, frontier molecular orbital and molecular electrostatic potential calculations revealed that CV-OTES-Cn has excellent optical properties and electron injection ability. In particular, the characteristics of the unbent conformation of CV-OTES-Cn are expected to contribute significantly to the photocurrent in TiO2-based photocatalysts and DSSCs. These findings enhance the understanding of the covalent attachment strategy using SCAs and contribute to improving TiO2-based photocatalysts and DSSCs.

Nerolidol ameliorates cyclophosphamide-induced oxidative stress, neuroinflammation and cognitive dysfunction: Plausible role of Nrf2 and NF- κB.

AIM: Cyclophosphamide (CP) is a potent anticancer and immunosuppressant drug. Studies have shown significant oxidative stress and cognitive impairment but neuroinflammatory and histological aberrations with its administration is underexplored. Nerolidol (NER) is a lipophilic bioactive molecule with antioxidant and anti-inflammatory properties but it has not been explored for neuroprotective potential in CP-induced neurotoxic manifestations. Therefore, in the present study, we aimed to evaluate the neuroprotective potential of NER in CP-induced neuroinflammation and associated comorbid conditions like depression and cognitive dysfunctions. MATERIALS AND METHOD: In-silico study using Schrödinger software was used to assess the binding affinity of NER with Nrf2. In the In vivo study, NER 200 and 400 mg/kg p.o. were given from 1st day to 14th day. CP 200 mg/kg, i.p., was administered on the 7th day. After 24 h of the last dosing, neurobehavioral tests like spontaneous body alternation, passive avoidance and forced swim test were performed. On completion of study, mice were sacrificed, hippocampus and cortex were removed for biochemical estimations, histopathology and immunohistochemistry of p65 NF- κB and Nrf2. KEY FINDINGS: In-silico study showed significant binding of NER into the pocket domain of Nrf2. In-vivo study showed protective effect of NER against CP-induced neuroinflammation, oxidative stress, cognitive impairment and structural abnormalities in the hippocampus and cortex regions. SIGNIFICANCE: Findings of the study suggested that NER is a potential therapeutic molecule which can mitigate CP-induced neurotoxic manifestations via Nrf2 and NF-κB pathway. However, more detailed studies are needed to explicate the mechanism underlying its neuroprotective effect.

Comparison of unbiased stereological estimation of total number of cresyl violet stained neurons and parvalbumin positive neurons in the adult human spiral ganglion.

Estimation of total number of neurons in the spiral ganglion (SG) at various ages and their functional status is important as these neurons are constantly exposed to noise and other environmental factors that may lead to neuronal loss with aging due to excitotoxic damage. Parvalbumin (PV) is a calcium-binding protein (CBP), found in highly metabolically active neurons. It helps in buffering cytosolic calcium, which is essential for neurotransmitter release. The neurons in the adult human SG express PV more strongly than other CBPs like calbindin and calretinin. These CBPs can be used as signatures to recognise neurons. In the present study, we quantified the number of neurons expressing PV by unbiased stereology and compared it to the number of neurons stained by cresyl violet (CV), which is a Nissl stain, in the adult human SG. Five adult human cadaveric temporal bones were obtained from the forensic science mortuary, after due clearance from the institute ethics committee. Independent CV stained and PV immunostained sections were used to estimate the total number of neurons (optical fractionator), with StereoInvestigator (SI) software. The estimated total number of SG neurons was 27,485±3251 and 26,705±1823 in the PV and CV stained sections, respectively. There was no significant difference between the estimates (p=0.552). Therefore, CV staining is simpler and more cost effective when estimating neuronal number. Although PV stains spiral ganglion neurons (SGNs) with a greater intensity and provides a functional status, its tedious protocol limits its use for quantification.

Laser Capture Microdissection and Isolation of High-Quality RNA from Frozen Endometrial Tissue.

Laser capture microdissection (LCM) allows expression profiling of specific cell populations within tissues. However, isolation of high-quality RNA from laser capture microdissected frozen tissue is beset by problems arising from intrinsic tissue RNase activity. Herein, we describe an optimized staining/LCM/RNA extraction protocol developed for the isolation of epithelial RNA from frozen tissue sections using human endometrial cancer as a model tissue. This method combines excellent, reproducible visualization of tissue morphology with the isolation of high-integrity RNA suitable for downstream applications such as expression microarray analysis. We present quantitative and qualitative RNA data obtained from >200 endometrial epithelial samples (normal, hyperplastic, and cancerous), where 92% of samples had RIN values of 7 and above and highlight common pitfalls faced by investigators. This method should also be broadly applicable to a range of other tissue types.

Exposure to Enriched Environment Restores Altered Passive Avoidance Learning and Ameliorates Hippocampal Injury in Male Albino Wistar Rats Subjected to Chronic Restraint Stress.

AIMS: The aim of the study was to investigate the effects of exposure to enriched environment (EE) on passive avoidance learning and hippocampal cellular morphology in rats exposed to chronic restraint stress. MATERIALS AND METHODS: Adult male albino Wistar rats were assigned into the following groups: normal control (NC) remained undisturbed in their home cages; stressed group (S) subjected to restrained stress (6 h/day) followed by housing in standard housing for 21 days; And stressed + EE (S + EE) subjected to restrained stress followed by housing in EE for 21 days. On 22nd day, six animals from each of the three groups were exposed to passive avoidance test. The remaining animals were sacrificed. Hippocampus was isolated and processed for cellular morphology using cresyl violet staining. STATISTICAL ANALYSIS USED: Data were analyzed using one-way analysis of variance followed by Tukey's multiple comparison test (post hoc). RESULTS: Stressed rats exposed to EE showed significant improvement in passive avoidance learning test compared to NC. Quantification of the surviving neurons in the hippocampal subfields and their cellular morphology revealed significant neuroprotection in S + EE in cornu ammonis-2 (CA2) neurons and CA3 hippocampal neurons. No significant changes were found in CA1 hippocampal subfield. CONCLUSIONS: The outcome of this study makes us to think the possibilities of adopting EE as an alternative strategy in brain diseases where there is chronic stress and to minimize the impairment in learning and memory.

Confocal scanning microscopy provides rapid, detailed intraoperative histological assessment of brain neoplasms: Experience with 106 cases.

OBJECTIVES: Frozen section histological analysis is currently the mainstay for intraprocedural tissue diagnosis during the resection of intracranial neoplasms and for evaluating tumor margins. However, frozen sections are time-consuming and often do not reveal the histological features needed for final diagnosis when compared with permanent sections. Confocal scanning microscopy (CSM) with certain stains may be a valuable technology that can add rapid and detailed histological assessment advantage for the neurosurgical operating room. This study describes potential advantages of CSM imaging of fresh human brain tumor tissues labeled with acriflavine (AF), acridine orange (AO), cresyl violet (CV), methylene blue (MB), and indocyanine green (ICG) within the neurosurgical operating room facility. PATIENTS AND METHODS: Acute slices from orthotopic human intracranial neoplasms were incubated with AF/AO and CV solutions for 10 s and 1 min respectively. Staining was also attempted with MB and ICG. Samples were imaged using a bench-top CSM system. Histopathologic features of corresponding CSM and permanent hematoxylin and eosin images were reviewed for each case. RESULTS: Of 106 cases, 30 were meningiomas, 19 gliomas, 13 pituitary adenomas, 9 metastases, 6 schwannomas, 4 ependymomas, and 25 other pathologies. CSM using rapid fluorophores (AF, AO, CV) revealed striking microvascular, cellular and subcellular structures that correlated with conventional histology. By rapidly staining and optically sectioning freshly resected tissue, images were generated for intraoperative consultations in less than one minute. With this technique, an entire resected tissue sample was imaged and digitally stored for tele-pathology and archiving. CONCLUSION: CSM of fresh human brain tumor tissue provides clinically meaningful and rapid histopathological assessment much faster than frozen section. With appropriate stains, including specific cellular structure or antibody staining, CSM could improve the timeliness of intraoperative decision-making, and the neurosurgical-pathology workflow during resection of human brain tumors, ultimately improving patient care.

Asymmetric Changes in Limbic Cortex and Planum Temporale in Patients with Alzheimer Disease.

BACKGROUND: There are several cortical areas related to the limbic system that form the output from the hippocampal formation whose cellular and morphological features are important for the onset and progression of AD. We hypothesized that there would be a significant difference in the size of cortical pyramidal neurons and that there would also be a hemispheric asymmetry between Alzheimer disease patients and controls. These differences would potentially be accompanied by an increase in the numbers of Fluoro-Jade B-positive degenerating cortical neurons and a corresponding decrease in the numbers of DAPI-stained cortical neuronal nuclei in subjects with AD compared to controls. Such changes could potentially be used as another marker in postmortem neuropathological diagnosis of AD. METHODS: We measured absolute numbers of DAPI and Fluoro-Jade B stained cells in five cortical areas of the limbic system and four subareas of planum temporale in the post-mortem brains of subjects with Alzheimer disease. We also measured the size of pyramidal neurons in layer III in the five cortical areas of the limbic system in these subjects. All measurements were performed separately for the left and right hemisphere in order to identify asymmetries between the two hemispheres. RESULTS: We observed a significant decrease in numbers of DAPI stained cells in layers IV-VI of the anterior cingulate gyrus on the right side, in layers I-III of the posterior cingulate gyrus on the left side, in layers IV-VI in the transition region from superior temporal gyrus into planum temporale on the right and in layers IV-VI in the transition from planum temporale to insular cortex on the left. We also observed a significant increase in the numbers of Fluoro-Jade stained cells in layers I-III of the anterior cingulate gyrus and in layers I-III on the left and layers IV-VI of the right gyrus of Heschl. Shortening of the size of layer III pyramidal neurons in subjects with Alzheimer´s disease was found in the anterior cingulate gyrus on the right, in the posterior cingulate gyrus and entorhinal cortex on the left and on the right in the parahippocampal gyrus. CONCLUSION: Our study demonstrates asymmetries in different cortical regions of the temporal lobe that can be used as another marker in the postmortem diagnosis of AD.