Reduction in neurons immunoreactive for calcium-binding proteins in the anteroventral thalamic nuclei of individuals with down syndrome.

The anterior thalamic nuclei are important for cognition, and memory in particular. However, little is known about how the anterior thalamic nuclei are affected in many neurological disorders partly due to difficulties in selective segmentation in in vivo scans, due to their size and location. Post-mortem studies, therefore, remain a valuable source of information about the status of the anterior thalamic nuclei. We used post-mortem tissue to assess the status of the anteroventral thalamic nucleus in Down syndrome using samples from males and females ranging from 22-65 years in age and comparing to tissue from age matched controls. As expected, there was increased beta-amyloid plaque expression in the Down syndrome group. While there was a significant increase in neuronal density in the Down syndrome group, the values showed more variation consistent with a heterogeneous population. The surface area of the anteroventral thalamic nucleus was smaller in the Down syndrome group suggesting the increased neuronal density was due to greater neuronal packing but likely fewer overall neurons. There was a marked reduction in the proportion of neurons immunoreactive for the calcium-binding proteins calbindin, calretinin, and parvalbumin in individuals with Down syndrome. These findings highlight the vulnerability of calcium-binding proteins in the anteroventral nucleus in Down syndrome, which could both be driven by, and exacerbate, Alzheimer-related pathology in this region.

Basal release and relaxation responses to 6-nitrodopamine in swine carotid, coronary, femoral, and renal arteries.

Mammalian and reptilian vascular tissues present basal release of 6-nitrodopamine, which is reduced when the tissues are pre-incubated with the NO synthase inhibitor L-NG-Nitro arginine methyl ester (L-NAME), or when the endothelium is mechanically removed. 6-Nitrodopamine induces vasorelaxation in pre-contracted vascular rings by antagonizing the dopaminergic D2-like receptor. Here it was investigated whether male swine vessels (including carotid, left descendent coronary, renal, and femoral arteries) release 6-nitrodopamine, dopamine, noradrenaline, and adrenaline, as measured by liquid chromatography coupled to tandem mass spectrometry. The in vitro vasorelaxant action of 6-nitrodopamine was evaluated in carotid, coronary, renal, and femoral arteries precontracted by U-46619 (3 nM), and compared to that induced by the dopamine D2-receptor antagonist L-741,626. Expression of tyrosine hydroxylase and the neuromaker calretinin was investigated by immunohistochemistry. All vascular tissues presented basal release of endothelium-derived catecholamines. The relaxation induced by 6-nitrodopamine was not affected by preincubation of the tissues with either L-NAME (100 µM, 30-min preincubation) or the heme-site inhibitor of soluble guanylyl cyclase ODQ (100 µM, 30-min preincubation). Electrical field stimulation (EFS)-induced contractions were significantly potentiated by previous incubation with L-NAME, but unaffected by ODQ preincubation. The contractions induced by EFS were reduced by preincubation with either 6-nitrodopamine or L-741,626. Immunohistochemistry in all arteries revealed the presence of tyrosine hydroxylase in the endothelium, whereas immunoreactivity for calretinin was negative. Swine vessels present basal release of endothelium-derived catecholamines and expression of tyrosine hydroxylase in the endothelium. The vasodilation induced by 6-nitrodopamine is due to blockade of dopaminergic D2-like receptors.

Inner Structure of the Lateral Geniculate Complex of Adult and Newborn Acomys cahirinus.

Acomys cahirinus is a unique Rodentia species with several distinctive physiological traits, such as precocial development and remarkable regenerative abilities. These characteristics render A. cahirinus increasingly valuable for regenerative and developmental physiology studies. Despite this, the structure and postnatal development of the central nervous system in A. cahirinus have been inadequately explored, with only sporadic data available. This study is the first in a series of papers addressing these gaps. Our first objective was to characterize the structure of the main visual thalamic region, the lateral geniculate complex, using several neuronal markers (including Ca2+-binding proteins, glutamic acid decarboxylase enzyme, and non-phosphorylated domains of heavy-chain neurofilaments) to label populations of principal neurons and interneurons in adult and newborn A. cahirinus. As typically found in other rodents, we identified three subdivisions in the geniculate complex: the dorsal and ventral lateral geniculate nuclei (LGNd and LGNv) and the intergeniculate leaflet (IGL). Additionally, we characterized internal diversity in the LGN nuclei. The "shell" and "core" regions of the LGNd were identified using calretinin in adults and newborns. In adults, the inner and outer parts of the LGNv were identified using calbindin, calretinin, parvalbumin, GAD67, and SMI-32, whereas in newborns, calretinin and SMI-32 were employed for this purpose. Our findings revealed more pronounced developmental changes in LGNd compared to LGNv and IGL, suggesting that LGNd is less mature at birth and more influenced by visual experience.

The potential protective effect of Camellia Sinensis in mitigating monosodium glutamate-induced neurotoxicity: biochemical and histological study in male albino rats.

Monosodium glutamate (MSG) is the sodium compound derived from glutamic acid. Excessive daily ingestion of MSG leads to elevated amounts of glutamic acid in the bloodstream, which can be detrimental to brain structures. Camellia sinensis, often known as green tea (GT), is a rich source of essential hexogen antioxidants that are necessary for the body. Thirty-two adult male albino rats were divided into four groups (n = 8). Group 1 served as a control -ve group. Group 2 was given GT (1.5 ml/rat/day). Group 3 was given MSG (600 mg/kg/day). Group 4 was given MSG (600 mg/kg/day) and GT (1.5 ml/rat/day). All treatments were given orally for 28 days. MSG administration resulted in significant neurotoxicity in rats that was revealed by the significant reduction of serum concentration of glutathione peroxidase (GPx) and nitric oxide (NO), and the significant elevation of total antioxidant capacity (TAC) accompanied by the significant reduction of levels of serum monoamines (dopamine, serotonin, and norepinephrine) and histological changes in the hippocampus area CA1, dentate gyrus, and cerebellar cortex and positive immunohistochemical staining of glial fibrillary acidic proteins (GFAP) and calretinin. Administration of GT with MSG counteracted the MSG-mediated oxidative stress by significantly increasing serum concentrations of GPX and NO and significantly decreasing concentrations of TAC. Furthermore, GT significantly increased levels of serum monoamines (dopamine, serotonin, and norepinephrine). Moreover, it ameliorated the histological changes, GFAP, and calretinin immunostaining in brain tissues. It is envisaged that GT will serve as a viable protective choice for the inclusion of the neurotoxicity treatment procedure.

Maturation of type I and type II rat vestibular hair cells in vivo and in vitro.

Vestibular sensory epithelia contain type I and type II sensory hair cells (HCI and HCII). Recent studies have revealed molecular markers for the identification of these cells, but the precise composition of each vestibular epithelium (saccule, utricle, lateral crista, anterior crista, posterior crista) and their postnatal maturation have not been described in detail. Moreover, in vitro methods to study this maturation are not well developed. We obtained total HCI and HCII counts in adult rats and studied the maturation of the epithelia from birth (P0) to postnatal day 28 (P28). Adult vestibular epithelia hair cells were found to comprise ∼65% HCI expressing osteopontin and PMCA2, ∼30% HCII expressing calretinin, and ∼4% HCII expressing SOX2 but neither osteopontin nor calretinin. At birth, immature HCs express both osteopontin and calretinin. P28 epithelia showed an almost adult-like composition but still contained 1.3% of immature HCs. In addition, we obtained free-floating 3D cultures of the epithelia at P1, which formed a fluid-filled cyst, and studied their survival and maturation in vitro up to day 28 (28 DIV). These cultures showed good HC resiliency and maturation. Using an enriched medium for the initial 4 days, a HCI/calretinin+-HCII ratio close to the in vivo ratio was obtained. These cultures are suitable to study HC maturation and mature HCs in pharmacological, toxicological and molecular research.

Combination of calretinin, MALAT1, and GAS5 as a potential prognostic biomarker to predict disease progression in surgically treated mesothelioma patients.

BACKGROUND: The role of cytoreductive surgery for epithelioid pleural mesothelioma within a multimodal treatment approach remains controversial. Carefully selected patients benefit from cytoreductive surgery and adjuvant chemotherapy, but there is no established biomarker to predict tumor recurrence or progression during the course of the disease. The aim of this study was to identify potential biomarkers to predict therapeutic response in terms of progression-free survival. METHODS: Between 03/2014 and 08/2022, preoperative blood samples were collected from 76 patients with epithelioid pleural mesothelioma who underwent cytoreductive surgery as part of a multimodal treatment approach. Identification of potential biomarkers was performed by determination of mesothelin and calretinin, as well as specific long non-coding RNAs and microRNAs. Receiver operating characteristic analysis, Kaplan-Meier survival analysis, and Cox regression were used to assess the association between biomarker concentrations and patient recurrence status and survival. RESULTS: MALAT1, GAS5, and calretinin showed statistically significant increased biomarker levels in patients with recurrence in contrast to recurrence-free patients after surgical treatment (p < 0.0001, p = 0.0190, and p = 0.0068, respectively). The combination of the three biomarkers resulted in a sensitivity of 68 % and a specificity of 89 %. CONCLUSION: MALAT1, GAS5, and calretinin could be potential biomarkers for the prediction of tumor recurrence, improving the benefit from multimodal treatment including cytoreductive surgery.

Case report: Abdominal mesothelioma in Atelerix albiventris.

Hedgehogs, as exotic species, are more susceptible to various neoplastic conditions affecting diverse bodily systems, particularly the tegumentary, hemolymphatic, and digestive systems. Among these conditions, epithelial tumors are the most prevalent, followed by round cell tumors and mesenchymal tumors. A striking characteristic is the malignant nature of over 8% of these tumors, leading to a generally unfavorable prognosis. This study aims to present a unique case involving a 2.5 year-old male African pygmy hedgehog in Concepción, Biobío District, Chile, diagnosed with a mesenchymal neoplasia originating from mesothelial cells. The hedgehog presented to the veterinary clinic with acute abdominal pain, prompting ultrasound imaging, and comprehensive cytological, histopathological, and immunohistochemical analyses. During abdominal ultrasound, a mass was observed, and its cytological examination revealed the presence of malignant cells. The histopathological examination unveiled a diffuse mesothelial cell tissue interwoven with abundant fibrous tissue and small cysts containing serous fluid, all enveloped by flattened or cuboidal cells of mesothelial origin. Immunohistochemistry further confirmed the diagnosis, demonstrating positive immunostaining for calretinin and mesothelin markers, corroborating the diagnosis of fibrous malignant peritoneal mesothelioma. This case highlights the complexity of neoplastic conditions in hedgehogs and emphasizes the importance of multimodal diagnostic approaches for accurate identification and understanding of these rare diseases.

Expression of Calretinin Expression in Odontogenic Cysts and Odontogenic Tumors - Original Research.

Aim: The present study was conducted for assessing variability in calretinin expression among odontogenic cysts as well as tumor cases. Materials and Methods: Fifteen cases were included in the present research consisting of cases like - dentigerous cyst, odontogenic keratocyst, apical radicular cyst along with tumors like ameloblastoma, ameloblastic carcinoma, adenomatoid odontogenic tumor. Calretinin antibody was used for immunohistochemical staining. The amount of expression of this calretinin was statistically analyzed with the help of Chi-square test where P < 0.05 was considered noteworthy statistically. Results: Most cases of ameloblastomas were highly positive for calretinin expression as compared to other cysts and tumors. Therefore, the correlation of this variation of expression of calretinin was statistically noteworthy (P = 0.00). Conclusion: In this study, we concluded that for ameloblastomas, calretinin can be a specific marker immunohistochemically and can help in identifying the amount of aggressive spread of various odontogenic tumors.

Clinical Relevance of Pathological Diagnosis of Hirschsprung's Disease with Acetylcholine-Esterase Histochemistry or Calretinin Immunohistochemistry.

INTRODUCTION: Hirschsprung disease (HD) manifests as a developmental anomaly affecting the enteric nervous system, where there is an absence of ganglion cells in the lower part of the intestine. This deficiency leads to functional blockages within the intestines. HD is usually confirmed or ruled out through rectal biopsy. The identification of any ganglion cells through hematoxylin and eosin (H&E) staining rules out HD. If ganglion cells are absent, further staining with acetylcholine-esterase (AChE) histochemistry or calretinin immunohistochemistry (IHC) forms part of the standard procedure for determining a diagnosis of HD. In 2017, our Institute of Pathology at University Hospital of Heidelberg changed our HD diagnostic procedure from AChE histochemistry to calretinin IHC. In this paper, we report the impact of the diagnostic procedure change on surgical HD therapy procedures and on the clinical outcome of HD patients. METHODS: We conducted a retrospective review of the diagnostic procedures, clinical data, and postoperative progress of 29 patients who underwent surgical treatment for HD in the Department of Pediatric Surgery, University of Heidelberg, between 2012 and 2021. The patient sample was divided into two groups, each covering a treatment period of 5 years. In 2012-2016, HD diagnosis was performed exclusively using AChE histochemistry (AChE group, n = 17). In 2017-2021, HD diagnosis was performed exclusively using calretinin IHC (CR group, n = 12). RESULTS: There were no significant differences between the groups in sex distribution, weeks of gestation, birth weight, length of the aganglionic segment, or associated congenital anomalies. Almost half of the children in the AChE group, twice as many as in the CR group, required an enterostomy before transanal endorectal pull-through procedure (TERPT). In the AChE group, 4 patients (23.5%) required repeat bowel sampling to confirm the diagnosis. Compared to the AChE group, more children in the CR group suffered from constipation post TERPT. DISCUSSION: Elevated AChE expression is linked to hypertrophied extrinsic cholinergic nerve fibers in the aganglionic segment in the majority of patients with HD. The manifestation of increased AChE expression develops over time. Therefore, in neonatal patients with HD, especially those in the first 3 weeks of life, an increase in AChE reaction is not detected. Calretinin IHC reliably identifies the presence or absence of ganglion cells and offers multiple benefits over AChE histochemistry. These include the ability to perform the test on paraffin-embedded tissue sections, a straightforward staining pattern, a clear binary interpretation (negative or positive), cost-effectiveness, and utility regardless of patient age. CONCLUSIONS: The ability of calretinin IHC to diagnose HD early and time-independently prevented repeated intestinal biopsies in our patient population and allowed us to perform a one-stage TERPT in the first months of life, reducing the number of enterostomies and restoring colonic continuity early. Patients undergoing transanal pull-through under the age of 3 months require a close follow-up to detect cases with bowel movement problems.

Expression of Calretinin in the Cecal Muscularis Interna: Observation and Hypothetical Relevance to Appendicitis.

BACKGROUND: The unexpected observation of calretinin immunoreactivity in smooth muscle cells in the muscularis propria of the cecum led to a more detailed examination of calretinin expression and its possible relationship to propulsive contractile activity around the vermiform appendix. METHODS: Immunohistochemistry and RNA in situ hybridization were performed to analyze calretinin expression in intestinal samples from 33 patients at ages ranging from mid-gestation fetuses to adults, as well as in some potentially relevant animal models. Dual immunolabeling was done to compare calretinin localization with markers of smooth muscle and interstitial cells of Cajal. RESULTS: Calretinin expression was observed consistently in the innermost smooth muscle layers of the muscularis interna in the human cecum, appendiceal base, and proximal ascending colon, but not elsewhere in the intestinal tract. Calretinin-positive smooth muscle cells did not co-express markers located in adjacent interstitial cells of Cajal. Muscular calretinin immunoreactivity was not detected in the ceca of mice or macaques, species which lack appendices, nor in the rabbit cecum or appendix. CONCLUSIONS: Localized expression of calretinin in cecal smooth muscle cells may reduce the likelihood of retrograde, calcium-mediated propulsive contractions from the proximal colon and suppress pro-inflammatory fecal stasis in the appendix.

Distribution of calcium-binding proteins immunoreactivity in the bottlenose dolphin entorhinal cortex.

Introduction: The entorhinal cortex has been shown to be involved in high-level cognitive functions in terrestrial mammals. It can be divided into two main areas: the lateral entorhinal area (LEA) and the medial entorhinal area (MEA). Understanding of its structural organization in cetaceans is particularly important given the extensive evidence for their cognitive abilities. The present study describes the cytoarchitectural and immunohistochemical properties of the entorhinal cortex of the bottlenose dolphin (Tursiops truncatus, Montagu, 1821), perhaps the most studied cetacean species and a paradigm for dolphins and other small cetaceans. Methods: Four bottlenose dolphins' entorhinal cortices were processed. To obtain a precise overview of the organization of the entorhinal cortex we used thionin staining to study its laminar and regional organization, and immunoperoxidase technique to investigate the immunohistochemical distribution of three most commonly used calcium-binding proteins (CBPs), calbindin D-28k (CB), calretinin (CR) and parvalbumin (PV). Entorhinal cortex layers thickness were measured, morphological and morphometric analysis for each layer were conducted and statistically compared. Results: Six layers in both the LEA and MEA were identified. The main difference between the LEA and the MEA is observed in layers II and III: the neurons in layer II of the LEA were denser and larger than the neurons in layer II of MEA. In addition, a relatively cell-free zone between layers II and III in LEA, but not in MEA, was observed. The immunohistochemical distribution of the three CBPs, CB, CR and PV were distinct in each layer. The immunostaining pattern of CR, on one side, and CB/PV, on the other side, appeared to be distributed in a complementary manner. PV and CB immunostaining was particularly evident in layers II and III, whereas CR immunoreactive neurons were distributed throughout all layers, especially in layers V and VI. Immunoreactivity was expressed by neurons belonging to different morphological classes: All CBPs were expressed in non-pyramidal neurons, but CB and CR were also found in pyramidal neurons. Discussion: The morphological characteristics of pyramidal and non-pyramidal neurons in the dolphin entorhinal cortex are similar to those described in the entorhinal cortex of other species, including primates and rodents. Interestingly, in primates, rodents, and dolphins, most of the CBP-containing neurons are found in the superficial layers, but the large CR-ir neurons are also abundant in the deep layers. Layers II and III of the entorhinal cortex contain neurons that give rise to the perforant pathway, which conveys most of the cortical information to the hippocampal formation. From the hippocampal formation, reciprocal projections are directed back to the deep layer of the entorhinal cortex, which distributes the information to the neocortex and subcortical area. Our data reveal that in the dolphin entorhinal cortex, the three major CBPs label morphologically heterogeneous groups of neurons that may be involved in the information flow between entorhinal input and output pathways.

BAP1, Wilms' tumor 1, and calretinin in predicting survival and response to first-line chemotherapy in patients with pleural mesothelioma.

PURPOSE: There are currently no methods to predict response to chemotherapy in pleural mesothelioma (PM). The aim of this study is to investigate the predictive and prognostic role of BAP1, WT1 and calretinin expression and their combinations in pre-treatment tumor samples by immunohistochemical (IHC) staining. METHODS: The study included consecutive PM patients treated with chemotherapy alone at a University hospital between 2009 and 2020. BAP1 analyses were performed on formalin-fixed, paraffin-embedded tumor tissue samples of the patients, while WT1 and calretinin information were obtained from the histopathological diagnosis records. RESULTS: Of the total 107 patients included, 64% had loss of BAP1 expression, whereas 77% had WT1 and 86% had calretinin expression. Patients with the presence of BAP1 expression, one or both of the other two markers, or loss of expression of all three markers (unfavorable status) were more likely to not respond to chemotherapy than those with the presence of all three markers or loss of BAP1 expression and expression of one or two other markers (favorable status) (p = 0.001). Median survival time of patients with favorable and unfavorable status was 15 ± 1.7 and 8.0 ± 2.4 months, respectively (p = 0.027). After adjustment for histopathology and stage, loss of BAP1 (HR = 0.54, 95%CI 0.35-0.83), WT1 (1.75, 1.06-2.90), calretinin (2.09, 1.14-3.84) expression and favourable panel (0.50, 0.27-0.92) was associated with prognosis. CONCLUSIONS: The IHC biomarkers BAP1, WT1, and calretinin, used in the routine diagnosis of PM and their combinations, are the first biomarkers associated with response to chemotherapy and may be a useful tool to select patients for first-line platinum pemetrexed treatment in PM patients. Validation in a large cohort is ongoing.

Temporospatial dynamics of the morphogenesis of the rabbit retina from prenatal to postnatal life: Light and electron microscopic study.

The retina consists of various cell types arranged in eight cell layers and two membranes that originate from the neuroectodermal cells. In this study, the timing of differentiation and distribution of the cellular components and the layers of the rabbit retina are investigated using light and electron microscopy and immunohistochemical techniques. There were 32 rabbit embryos and 12 rabbits used. The rabbit retina begins its prenatal development on the 10th day of gestation in the form of optic cup. The process of neuro- and gliogenesis occurs in several stages: In the first stage, the ganglionic cells are differentiated at the 15th day. The second stage includes the differentiation of Muller, amacrine, and cone cells on the 23rd day. The differentiation of bipolar, horizontal, and rod cells and formation of the inner segments of the photoreceptors consider the late stage that occurs by the 27th and 30th day of gestation. On the first week of age postnatally, the outer segments of the photoreceptors are developed. S100 protein is expressed by the Muller cells and its processes that traverse the retina from the outer to the inner limiting membranes. Calretinin is intensely labeled within the amacrine and displaced amacrine cells. Ganglionic cells exhibited moderate immunoreactivity for calretinin confined to their cytoplasm and dendrites. In conclusion, all stages of neuro- and gliogenesis of the rabbit retina occur during the embryonic period. Then, the retina continues its development postnatally by formation of the photoreceptor outer segments and all layers of the retina become established. RESEARCH HIGHLIGHTS: The aim of this study is to investigate the morphogenesis of the rabbit retina during pre- and postnatal life. The primordia of the retina could be observed in the form of the optic cup. The ganglionic cells are the first cells to differentiate, while the photoreceptor cells are the last. S100 protein is expressed by the Muller cells and its processes. Calretinin is intensely labeled in the amacrine and displaced amacrine cells and moderately expressed in the cytoplasm and dendrites of ganglionic cells.

The association of genetic factors with serum calretinin levels in asbestos-related diseases.

BACKGROUND: Asbestos exposure is associated with different asbestos-related diseases, including malignant mesothelioma (MM). MM diagnosis is confirmed with immunohistochemical analysis of several markers, including calretinin. Increased circulating calretinin was also observed in MM. The aim of the study was to determine if CALB2 polymorphisms or polymorphisms in genes that can regulate calretinin expression are associated with serum calretinin levels or MM susceptibility. SUBJECTS AND METHODS: The study included 288 MM patients and 616 occupationally asbestos-exposed subjects without MM (153 with asbestosis, 380 with pleural plaques and 83 without asbestos-related disease). Subjects were genotyped for seven polymorphisms in CALB2, E2F2, MIR335, NRF1 and SEPTIN7 genes using competitive allele-specific polymerase chain reaction (PCR). Serum calretinin was determined with ELISA in 545 subjects. Nonparametric tests, logistic regression and receiver operating characteristic (ROC) curve analysis were used for statistical analysis. RESULTS: Carriers of at least one polymorphic CALB2 rs889704 allele had lower calretinin levels (P = 0.036). Carriers of two polymorphic MIR335 rs3807348 alleles had higher calretinin (P = 0.027), while carriers of at least one polymorphic NRF1 rs13241028 allele had lower calretinin levels (P = 0.034) in subjects without MM. Carriers of two polymorphic E2F2 rs2075995 alleles were less likely to develop MM (odds ratio [OR] = 0.64, 95% confidence interval [CI] = 0.43-0.96, P = 0.032), but the association was no longer significant after adjustment for age (P = 0.093). Optimal serum calretinin cut-off values differentiating MM patients from other subjects differed according to CALB2, NRF1, E2F2, and MIR335 genotypes. CONCLUSIONS: The results of presented study suggest that genetic variability could influence serum calretinin levels. These findings could contribute to a better understanding of calretinin regulation and potentially to earlier MM diagnosis.

Tasks and Experiences of the Prospective, Longitudinal, Multicenter MoMar (Molecular Markers) Study for the Early Detection of Mesothelioma in Individuals Formerly Exposed to Asbestos Using Liquid Biopsies.

Mesothelioma is an aggressive cancer, strongly associated with prior exposure to asbestos. Commonly, tumors are detected at late stages of the disease. Detection at early stages might be meaningful, because therapies might be more effective when the tumor burden is relatively low and the tumor has not spread to distant sites. Circulating biomarkers in blood might be a promising tool to improve the early detection of mesothelioma, but for screening in asymptomatic subjects, candidate biomarkers need to be validated in appropriate studies. This study was conducted to assess the performance of biomarkers in liquid biopsies to detect mesothelioma at early stages. Over a period of 10 years, 2769 volunteers formerly exposed to asbestos were annually examined and liquid biopsies were collected. A follow-up was completed 17 months after the last blood collection. The article provides a detailed overview of our lessons learned and experiences of conducting a prospective, longitudinal, multicenter study. The existing cohort of individuals at risk is highly suitable for the validation of blood-based biomarkers for the early detection of mesothelioma as well as lung cancer.

Localized pleural mesothelioma in a dog.

Malignant mesotheliomas with localized growth are extremely rare in dogs. A 9-year-old male dog presented with a localized tumour that originated from the parietal pleura and had polypoid growth in the thoracic cavity. Histological examination revealed that the tumour consisted of tubular formations with scattered cysts and minimal papillary growth pattern. Neoplastic cells were immunopositive for mesothelial markers (calretinin and Wilms' tumour gene 1) and negative for carcinoma markers (thyroid transcription factor 1 and tumour protein 63). The animal was alive with no recurrence or metastasis/dissemination 11 months after surgery. To the best of our knowledge, this is the first report of a localized mesothelioma in a dog without metastasis/dissemination and highlights the value of mesothelial markers for an accurate diagnosis.

Early Life Stress Enhances Cognitive Decline and Alters Synapse Function and Interneuron Numbers in Young Male APP/PS1 Mice.

BACKGROUND: Exposure to stress early in life increases the susceptibility to Alzheimer's disease (AD) pathology in aged AD mouse models. So far, the underlying mechanisms have remained elusive. OBJECTIVE: To investigate 1) effects of early life stress (ELS) on early functional signs that precede the advanced neuropathological changes, and 2) correlate synaptosomal protein content with cognition to identify neural correlates of AD. METHODS: APPswe/PS1dE9 mice and littermates were subjected to ELS by housing dams and pups with limited bedding and nesting material from postnatal days 2-9. At 3 months of age, an age where no cognitive loss or amyloid-ß (Aß) pathology is typically reported in this model, we assessed hippocampal Aß pathology, synaptic strength and synapse composition and interneuron populations. Moreover, cognitive flexibility was assessed and correlated with synaptosomal protein content. RESULTS: While ELS did not affect Aß pathology, it increased synaptic strength and decreased the number of calretinin+ interneurons in the hippocampal dentate gyrus. Both genotype and condition further affected the level of postsynaptic glutamatergic protein content. Finally, APP/PS1 mice were significantly impaired in cognitive flexibility at 3 months of age, and ELS exacerbated this impairment, but only at relatively high learning criteria. CONCLUSIONS: ELS reduced cognitive flexibility in young APP/PS1 mice and altered markers for synapse and network function. These findings at an early disease stage provide novel insights in AD etiology and in how ELS could increase AD susceptibility.

Interspecies Retinal Diversity and Optic Nerve Anatomy in Odontocetes.

Throughout evolution, odontocete vision has had to readapt to the aquatic environment, which has had far-reaching effects on ocular anatomy and neurology. The most prominent features include the iris with an operculum, a well-developed choroid, the presence of giant ganglion cells in the retina, and the hemispherical shape of the thick eyecup. In the present study, the optic nerve and the retina were comparatively studied in Odontoceti (Cuvier's beaked whale, common bottlenose dolphin, false killer whale, long-finned pilot whale, Risso's dolphin, striped dolphin), the semi-aquatic common hippopotamus, and the fully terrestrial bovine. Cross-sections of the tissue were treated with histological and immunohistochemical techniques. Substantial differences were seen between the odontocetes and the reference species as well as within the cetaceans. The morphological structure of the optic nerve mainly appeared species specific, while the density of retinal ganglion cells was significantly higher in the terrestrial bovine than in the cetaceans. However, some typical characteristics of the cetacean retina were absent: the giant ganglion cells and the high retinal thickness. Immunohistochemical research showed varying degrees of neurofilament 200 expression in the retinal ganglion cells, while calretinin was only expressed in those of the common bottlenose dolphin and bovine.

Vimentin Localization in the Zebrafish Oral Cavity: A Potential Role in Taste Buds Regeneration.

The morphology of the oral cavity of fish is related to their feeding habits. In this context, taste buds are studied for their ability to catch chemical stimuli and their cell renewal capacity. Vimentin RV202 is a protein employed as a marker for mesenchymal cells that can differentiate along different lineages and to self-renew, while Calretinin N-18 is employed as a marker of sensory cells, and ubiquitin is a protein crucial for guiding the fate of stem cells throughout development. In this study, a surface morphology investigation and an immunohistochemical analysis have been conducted. The results of the present study reveal, for the first time, the presence of Vimentin RV202 in a taste bud cell population of zebrafish. Some taste bud cells are just Vimentin RV202-immunoreactive, while in other cells Vimentin RV202 and Calretinin N-18 colocalize. Some taste buds are just reactive to Calretinin N-18. Vimentin RV202-immunoreactive cells have been observed in the connective layer and in the basal portion of the taste buds. The immunoreactivity of ubiquitin was restricted to sensory cells. Further studies are needed to elucidate the role of Vimentin RV202 in the maturation of taste bud cells, its potential involvement in the regeneration of these chemosensory organs, and its eventual synergic work with ubiquitin.

Secretagogin as a marker to distinguish between different neuron types in human frontal and temporal cortex.

The principal aim of the present work was to chemically characterize the population of neurons labeled for the calcium binding protein secretagogin (SCGN) in the human frontal and temporal cortices (Brodmann's area 10 and 21, respectively). Both cortical regions are involved in many high cognitive functions that are especially well developed (or unique) in humans, but with different functional roles. The pattern of SCGN immunostaining was rather similar in BA10 and BA21, with all the labeled neurons displaying a non-pyramidal morphology (interneurons). Although SCGN cells were present throughout all layers, they were more frequently observed in layers II, III and IV, whereas in layer I they were found only occasionally. We examined the degree of colocalization of SCGN with parvalbumin (PV) and calretinin (CR), as well as with nitric oxide synthase (nNOS; the enzyme responsible for the synthesis of nitric oxide by neurons) by triple immunostaining. We looked for possible similarities or differences in the coexpression patterns of SCGN with PV, CR and nNOS between BA10 and BA21 throughout the different cortical layers (I-VI). The percentage of colocalization was estimated by counting the number of all labeled cells through columns (1,100-1,400 µm wide) across the entire thickness of the cortex (from the pial surface to the white matter) in 50 µm-thick sections. Several hundred neurons were examined in both cortical regions. We found that SCGN cells include multiple neurochemical subtypes, whose abundance varies according to the cortical area and layer. The present results further highlight the regional specialization of cortical neurons and underline the importance of performing additional experiments to characterize the subpopulation of SCGN cells in the human cerebral cortex in greater detail.