Historical review: The golden age of the Golgi method in human neuropathology.

Golgi methods were used to study human neuropathology in the 1970s, 1980s, and 1990s of the last century. Although a relatively small number of laboratories applied these methods, their impact was crucial by increasing knowledge about: (1) the morphology, orientation, and localization of neurons in human cerebral and cerebellar malformations and ganglionic tumors, and (2) the presence of abnormal structures including large and thin spines (spine dysgenesis) in several disorders linked to mental retardation, focal enlargements of the axon hillock and dendrites (meganeurites) in neuronal storage diseases, growth cone-like appendages in Alzheimer disease, as well as abnormal structures in other dementias. Although there were initial concerns about their reliability, reduced dendritic branches and dendritic spines were identified as common alterations in mental retardation, dementia, and other pathological conditions. Similar observations in appropriate experimental models have supported many abnormalities that were first identified using Golgi methods in human material. Moreover, electron microscopy, immunohistochemistry, fluorescent tracers, and combined methods have proven the accuracy of pioneering observations uniquely visualized as 3D images of fully stained individual neurons. Although Golgi methods had their golden age many years ago, these methods may still be useful complementary tools in human neuropathology.

A CNN-based approach for joint segmentation and quantification of nuclei and NORs in AgNOR-stained images.

BACKGROUND AND OBJECTIVE: Oral cancer is the sixth most common kind of human cancer. Brush cytology for counting Argyrophilic Nucleolar Organizer Regions (AgNORs) can help early mouth cancer detection, lowering patient mortality. However, the manual counting of AgNORs still in use today is time-consuming, labor-intensive, and error-prone. The goal of our work is to address these shortcomings by proposing a convolutional neural network (CNN) based method to automatically segment individual nuclei and AgNORs in microscope slide images and count the number of AgNORs within each nucleus. METHODS: We systematically defined, trained and tested 102 CNNs in the search for a high-performing solution. This included the evaluation of 51 network architectures combining 17 encoders with 3 decoders and 2 loss functions. These CNNs were trained and evaluated on a new AgNOR-stained image dataset of epithelial cells from oral mucosa containing 1,171 images from 48 patients, with ground truth annotated by specialists. The annotations were greatly facilitated by a semi-automatic procedure developed in our project. Overlapping nuclei, which tend to hide AgNORs, thus affecting their true count, were discarded using an automatic solution also developed in our project. Besides the evaluation on the test dataset, the robustness of the best performing model was evaluated against the results produced by a group of human experts on a second dataset. RESULTS: The best performing CNN model on the test dataset consisted of a DenseNet-169 + LinkNet with Focal Loss (DenseNet-169 as encoder and LinkNet as decoder). It obtained a Dice score of 0.90 and intersection over union (IoU) of 0.84. The counting of nuclei and AgNORs achieved precision and recall of 0.94 and 0.90 for nuclei, and 0.82 and 0.74 for AgNORs, respectively. Our solution achieved a performance similar to human experts on a set of 291 images from 6 new patients, obtaining Intraclass Correlation Coefficient (ICC) of 0.91 for nuclei and 0.81 for AgNORs with 95% confidence intervals of [0.89, 0.93] and [0.77, 0.84], respectively, and p-values < 0.001, confirming its statistical significance. Our AgNOR-stained image dataset is the most diverse publicly available AgNOR-stained image dataset in terms of number of patients and the first for oral cells. CONCLUSIONS: CNN-based joint segmentation and quantification of nuclei and NORs in AgNOR-stained images achieves expert-like performance levels, while being orders of magnitude faster than the later. Our solution demonstrated this by showing strong agreement with the results produced by a group of specialists, highlighting its potential to accelerate diagnostic workflows. Our trained model, code, and dataset are available and can stimulate new research in early oral cancer detection.

Adapted technique for demonstrating argyrophilic nucleolar organizer regions in the cytologic samples of canine mast cell tumors.

INTRODUCTION: Argyrophilic nucleolar organizer regions (AgNORs) are nonhistone argyrophilic nucleolar proteins associated with ribosomal genes found in the nucleolar organizer region that reflect cell proliferation and have an affinity for silver. AgNOR staining may be useful to evaluate prognosis in several neoplasms because higher AgNOR counts are related to higher grade tumors, metastases, and shorter survival times. OBJECTIVE: We aimed to report on a quick and practical technique to identify AgNORs adapted for use in routine cytology. MATERIALS AND METHODS: The cytopathologic diagnosis of mast cell tumor (MCT) in samples collected by fine-needle aspiration (FNA) was determined. Next, slides were impregnated with a solution containing silver nitrate; the main modification of our technique included incubation of these slides at a controlled temperature of 25 °C. Some slides were previously stained with Diff-Quik and others were only fixed with methanol. The slides were analyzed under a microscope, and the number of blackened intranuclear points (AgNORs) was counted. RESULTS: Slides prestained with Diff-Quik were easily counted compared with slides only fixed in methanol. Technical issues encountered with the methanol-fixed slides included insufficient cellularity, background precipitation, and an absence of silver impregnation. CONCLUSIONS: The technique reported in this study showed satisfactory results for AgNOR counting in cytologic smears from MCT, such as good impregnation and the elimination of background interferents. Further evaluation of this method comparing AgNOR counts with histologic examinations, tumor grades, other prognostic markers, and survival times are needed to fully evaluate the benefit of this technique.

Whole-organism 3D quantitative characterization of zebrafish melanin by silver deposition micro-CT.

We previously described X-ray histotomography, a high-resolution, non-destructive form of X-ray microtomography (micro-CT) imaging customized for three-dimensional (3D), digital histology, allowing quantitative, volumetric tissue and organismal phenotyping (Ding et al., 2019). Here, we have combined micro-CT with a novel application of ionic silver staining to characterize melanin distribution in whole zebrafish larvae. The resulting images enabled whole-body, computational analyses of regional melanin content and morphology. Normalized micro-CT reconstructions of silver-stained fish consistently reproduced pigment patterns seen by light microscopy, and further allowed direct quantitative comparisons of melanin content across wild-type and mutant samples, including subtle phenotypes not previously noticed. Silver staining of melanin for micro-CT provides proof-of-principle for whole-body, 3D computational phenomic analysis of a specific cell type at cellular resolution, with potential applications in other model organisms and melanocytic neoplasms. Advances such as this in whole-organism, high-resolution phenotyping provide superior context for studying the phenotypic effects of genetic, disease, and environmental variables.

Combined Application of Immunohistochemistry and Warthin-Starry Silver Stain on the Pathologic Diagnosis of Cat Scratch Disease.

PURPOSE: Cat scratch disease (CSD) is an infectious disorder caused primarily by the bacterium Bartonella henselae (B. henselae). Immunohistochemistry (IHC) and Warthin-Starry silver stain (WS) are considered to be indispensable to diagnose CSD in combination with morphologic characteristics. In this study, we retrieved and reviewed 46 cases of paraffin-embedded lymphadenitis with histologic and/or clinical suspicion of CSD between 2014 and 2018, and detected B. henselae by IHC and WS, respectively, and evaluated the application significance of IHC and WS for the detection of B. henselae and validated their values in the pathologic diagnosis of CSD. MATERIALS AND METHODS: B. henselae was detected by IHC and WS; validation of 2 methods for detecting B. henselae was evaluated by sensitivity, specificity, false-positive rate, false-negative rate, precision, negative predictive value, and agreement rate. RESULTS: Microscopically, suppurative granulomas and/or multiple stellate microabscesses were observed in the accessory cortex of lymph nodes, especially near the subcapsule. Our results showed that 80.4% (37/46) of cases were positive for B. henselae by IHC, manifesting mainly punctuate, granular, or linear to outline the shape of bacteria. However, the positive rate of B. henselae by the WS method was 52.2% (24/46). There was a significant difference between IHC and WS (P=0.023). Moreover, a positive percentage of B. henselae was 97.8% (45/46), which was detected by the combined application of IHC and WS. The combination of IHC and WS exhibited high sensitivity (97.8%) and good agreement rate (86.5%). CONCLUSION: The combined application of the IHC and WS method may have important clinical advantages, which is with the highest sensitivity and agreement rate for pathologic diagnosis of CSD.

Liquid-based cytopathology test as a novel method to identify Aspergillus in patients with pulmonary aspergillosis.

Conventional cytopathology examination of respiratory samples can aid in identifying Aspergillus but with poor sensitivity, so this study aimed to assess the potential of the liquid-based cytopathology test (LCT) for improving the identification of Aspergillus in respiratory samples following Papanicolaou's or Special staining with Grocott's methenamine silver or periodic acid-Schiff staining. Paired bronchial brushing samples (n = 54) and sputum samples (n = 117) from 171 patients with pulmonary aspergillosis were prepared as slides using either conventional cytopathology or SurePath LCT. LCT slides were generally superior to conventional slides, showing smaller cell monolayer surface area, clearer background and more distinct stereoscopic cytological features. For Papanicolaou's staining, LCT-prepared slides allowed a higher positive rate of Aspergillus identification than conventional slides for bronchial brushing samples (59.25% vs. 20.37%, P < 0.05) and sputum samples (29.05% vs. 8.55%, P < 0.05). Similarly, Special staining of LCT-prepared slides showed a higher positive rate of Aspergillus identification for bronchial brushing samples (83.33% vs. 57.41%, P < 0.05) and sputum samples (43.59% vs. 19.66%, P < 0.05). This preliminary study suggests that LCT may be better than conventional slide preparation for identifying Aspergillus in respiratory samples from patients with pulmonary aspergillosis.

Avaliação da atividade proliferativa celular das lesões bucais causadas pelo uso de próteses totais através da impregnação tecidual pela prata / Proliferative cellular activity evaluation of lesions caused by dentures through tissue silver impregnation

Introdução: As próteses totais visam conservar a função do sistema estomatognático do paciente totalmente edêntulo. Porém, na mucosa bucal podem aparecer manifestações cuja principal causa são as próteses totais mal adaptadas. Objetivo: o presente estudo objetiva investigar a proliferação tecidual das lesões causadas por próteses totais removíveis através do método de impregnação pela prata (AgNOR), com isso facilitando o tratamento e a determinação do prognóstico das lesões a serem estudadas. Metodologia: foram selecionados todos os casos das lesões bucais mais comumente associadas à utilização de próteses totais registradas no Serviço de Diagnóstico Histopatológico do ICB­UPF nos anos de 2012 e 2013, tendo sido encontrados 5 casos de granuloma piogênico, 5 casos de hiperplasia de fundo de sulco, 5 casos de fibroma de irritação e 2 casos de fibroma ossificante periférico. Os cortes histopatológicos das lesões foram impregnados pela prata (método AgNOR), tendo sido obtido, com auxílio do programa Image Tool®, o número de NORs de 100 células de cada caso, resultando numa média de NORs em cada grupo de lesões. Resultados: os resultados obtidos foram tabulados em planilha eletrônica e a comparação do número médio de NORs de cada grupo foi realizado por meio do teste estatístico ANOVA, 5% de significância. Resultados: o grupo das hiperplasias de fundo de sulco mostrou média de 2,41 NORs por núcleo, o grupo dos granulo mas piogênicos mostrou 2,44, o fibroma de irritação 2,22, e o fibroma ossificante periférico mostrou média de 1,89 NORs por núcleo celular, diferindo estatisticamente esta lesão das anteriormente mencionadas (p = 0,002). Conclusão: o fibroma ossificante periférico mostrou ser a lesão causada por prótese total removível com a menor atividade proliferativa celular. Tal estudo precisa ser complementado por futuros estudos clínicos.

Introduction: the total dentures are aimed at preserving the function of the stomatognathic system of the fully edentulous patient. However, in the oral mucosa may appear manifestations whose main cause are the totally unsuitable dentures. Objective: this study aims to investigate the proliferation of tissue lesions caused by removable dentures by impregnation method for silver (AgNOR), thereby facilitating the treatment and determining the prognosis of the lesions to be studied. Methodology: we selected all cases of oral lesions most commonly associated with the use of dentures recorded in Histopathological Diagnostic Service ICB-UPF in the years 2012 and 2013, having been found 5 cases of pyogenic granuloma, 5 cases of hyperplasia, 5 cases of irritation fibroma and 2 cases of peripheral ossifying fibroma. Histopathological lesions cuts were impregnated by silver (AgNOR method), having been obtained with the aid of the program Image Tool®, the number of NOR cells 100 in each case, resulting in an average NORs in every group of lesions. Results: the results were tabulated in a spreadsheet and comparing the average number of NORs of each group was conducted through ANOVA, 5% significance level. Results: The group of hyperplasias showed average of 2.41 NORs per nucleus, the group of pyogenic granulomas showed 2.44, the irritation fibroma 2.22, and peripheral ossifying fibroma showed average of 1.89 NORs for cell nucleus, differing significantly from that of the aforementioned lesions (p = 0.002). Conclusion: the peripheral ossifying fibroma proved the injury caused by removable dentures with lower cell proliferative activity. This study needs to be complemented by future clinical studies.

Argyrophilic nucleolar organizing region associated protein synthesis for cytologic discrimination of follicular thyroid lesions.

Fine needle aspiration biopsy (FNAB) of the thyroid gland is an important tool for preoperative diagnosis; however, its benefit is limited for follicular lesions. Nucleolar organizer regions (NORs) are ribosomal gene regions that stain with silver (Ag) when they are active. These regions can be used to differentiate neoplastic and non-neoplastic lesions. We used a new AgNOR technique to investigate FNAB of cases diagnosed as follicular adenoma and carcinoma. Fourteen cases of follicular thyroid carcinoma (FTC) and 28 cases of thyroid follicular adenomas (FA) were stained using the silver NOR-associated protein (AgNOR) technique. One hundred nuclei per sample were examined, AgNORs were counted, and the total AgNOR area/nuclear area (TNORa/Na) ratio of each cell was calculated. We found that cases with FTC had significantly higher TNORa/Na than cases of FA. Also, cases with FTC had significantly higher AgNOR counts than cases with FA. AgNOR counting may help discriminate FTC and FA by routine cytopathology before surgery.

Development of a practical NF1 genetic testing method through the pilot analysis of five Japanese families with neurofibromatosis type 1.

OBJECTIVE: Mutation analysis of NF1, the responsible gene for neurofibromatosis type 1 (NF1), is still difficult due to its large size, lack of mutational hotspots, the presence of many pseudogenes, and its wide spectrum of mutations. To develop a simple and inexpensive NF1 genetic testing for clinical use, we analyzed five Japanese families with NF1 as a pilot study. METHODS: Our original method, CEL endonuclease mediated heteroduplex incision with polyacrylamide gel electrophoresis and silver staining (CHIPS) was optimized for NF1 mutation screening, and reverse transcription polymerase chain reaction (RT-PCR) was performed to determine the effect of transcription. Also, we employed DNA microarray analysis to evaluate the break points of the large deletion. RESULTS: A new nonsense mutation, p.Gln209(∗), was detected in family 1 and the splicing donor site mutation, c.2850+1G>T, was detected in family 2. In family 3, c.4402A>G was detected in exon 34 and the p.Ser1468Gly missense mutation was predicted. However mRNA analysis revealed that this substitution created an aberrant splicing acceptor site, thereby causing the p.Phe1457(∗) nonsense mutation. In the other two families, type-1 and unique NF1 microdeletions were detected by DNA microarray analysis. CONCLUSIONS: Our results show that the combination of CHIPS and RT-PCR effectively screen and characterize NF1 point mutations, and both DNA and RNA level analysis are required to understand the nature of the NF1 mutation. Our results also suggest the possibility of a higher incidence and unique profile of NF1 large deletions in the Japanese population as compared to previous studies performed in Europe.

Analysis of estrogen receptor ß interacting proteins using pull-down assay and MALDI-MS methods.

Estrogen mediates a plethora of functions through well-characterized estrogen receptor (ER)α and ERß after recruiting a number of interacting proteins. Various laboratories including ours have focused on the identification of ERß interacting proteins using different methods including matrix-assisted laser desorptive ionization (MALDI), which is a powerful technique in proteomics to identify new proteins present in low abundance. We have identified ERß interacting proteins resolved by one-dimensional preparatory sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) and two-dimensional SDS-PAGE followed by MALDI-MS. In this chapter, a detailed method of pull-down assay, SDS-PAGE, MALDI-MS, and immunoblotting along with the use of software for identification of interacting proteins have been described. Such methods are useful to identify the interacting proteins, which may predict the function and molecular mechanism of action that is helpful for developing therapeutic strategies.

Adaptación de la técnica de impregnación argéntica de Llombart para la demostración de fibras nerviosas, en cualquier tejido en cortes por parafina / Adaptation of Llombart's silver impregnation technique for demonstration of nerve fibers in any tissue in paraffin sections

En la investigación biológica sigue siendo necesaria la demostración de la inervación periférica en numerosos tejidos y órganos. El objetivo de este trabajo fue rescatar y modernizar uno de los métodos más constantes que hemos probado para demostrar la inervación periférica. La técnica de Llombart para fibras nerviosas se adaptó en cortes por parafina de 7 µm en diferentes tejidos animales. La impregnación argéntica se hizo por goteo en cámara húmeda. Se demostraron en forma constante, precisa y seriada terminaciones nerviosas y corpúsculos sensoriales, neuronas y fibras nerviosas periféricas. A pesar de la alta especificidad para fibras nerviosas, la técnica no compromete el panorama tisular por lo que da bellas imágenes de conjunto. Sin ser una técnica para argentafinidad, demuestra claramente dos tipos de células argentafines en las glándulas adrenales. La adición de los reactivos metálicos en gotas y en cámara húmeda, ofrece una variante sumamente económica.

In Biological research is still necessary for the demonstration of the peripheral innervation in numerous tissues and organs. The aim of this study was to rescue and modernize one of the most consistent methods that we have tried to demonstrate peripheral innervation. Llombart's technique for nerve fibers was adapted by paraffin cuts of 7 µm in different animal tissue. The silver impregnation was done by dripping in a moist chamber. It was demonstrated in a constant, precise and serial form, nerve terminations, and sensorial corpuscles, neurons, and peripheral nerve fibers. Despite being highly specific to nerve fibers, the technique does not sacrifice tissue panorama so it gives beautiful images set. Without being a technique to argentaffin structures, it clearly shows two types of argentaffin cells in the adrenal glands. The addition of the metal reactive in droplets and in a humid chamber provides a very economical variant.

Image analysis of platelet derived growth factor receptor-beta (PDGFRß) expression to determine the grade and dynamics of myelofibrosis in bone marrow biopsy samples.

BACKGROUND: Myelofibrosis (MF) is characterized by accumulation of stromal cells and extracellular matrix. Progression of fibrosis is an important clinical issue and monitoring is required for new therapeutic approaches. Currently, the quantification is based on semiquantitative evaluation of reticulin silver stained slides. We recently reported that platelet derived growth factor receptor beta (PDGFRß) expression in fibroblasts is a useful marker of stromal activation. PDGFRß expression based scores represent significant differences in different MF grade which provides optimal source of quantification. In this study, slide-based measurements were performed to support correlations of PDGFRß expression with MF grade. METHODS: Scanned image tiles from 79 bone marrow samples (BM) with different MF grades were evaluated for PDGFRß-related IHC parameters. Following the determination of immunopositive (brown component) and total area (region of interest) of the BM, PDGFRß related image parameters were defined and evaluated in comparison with the classical reticulin based grading. RESULTS: Eight PDGFRß expression related image parameters showed excellent correlation with the MF grade (correlation coefficient ranging between 0.79 and 0.83) and with PDGFRß score (0.76-0.87). Despite the significant sample heterogeneity, the parameters showed significant differences between fibrotic and nonfibrotic cases and between mild and advanced fibrosis. Distribution of values within a particular specimen emphasizes the heterogeneity of bone marrow involvement which may cause difficulties in semiquantitative methods. CONCLUSIONS: Our results clearly demonstrated the correlation between MF and PDGFRß expression considering all relevant areas in BM samples. This method provides good basis for follow-up comparison of the fibrotic samples.

Value of argyrophilic nucleolar organizing region protein determinations in nondiagnostic fine needle aspiration samples (due to insufficient cell groups) of thyroid nodules.

OBJECTIVE: To evaluate the diagnostic value of argyrophilic nucleolar organizing regions (AgNORs) in the nondiagnostic fine needle aspiration biopsy (NFNAB) specimens (due to insufficient cell groups) of cases with thyroid nodules. STUDY DESIGN: Thirty-five patients with NFNAB were included in the study. FNAB stained with Giemsa was faded using the McKee technique, then stained for AgNOR detection according to a specific protocol. One hundred nuclei per individual were evaluated to detect the AgNOR count/nucleus and total AgNOR area/ nuclear area (TNA/NA) of individual cells by using a computer program. RESULTS: The AgNOR values of patients with NFNAB were between 1.2-2.4% for AgNOR count/ nucleus and between 3.1-9.1%for TNA/NA. When the cutoff values were taken as > 3 for AgNOR count/nucleus and > 8 for TNA/NA, the sensitivity ratios were 100% and 97% for AgNOR count/nucleus and TNA/ NA for discriminating benign/malignant lesions. CONCLUSION: By using some cutoff values obtained from a modified AgNOR staining method, benign/malignant potential of thyroid aspirations with NFNAB may be estimated. (Anal Quant Cytopathol Histopathol

Determination of HER2 gene amplification in breast cancer using dual-color silver enhanced in situ hybridization (dc- SISH) and comparison with fluorescence ISH (FISH).

BACKGROUND: The two basic methods that are currently accepted to identify the HER2 status are immunohistochemistry and flyorescence in situ hybridization (FISH) . The aim of this study was to perform the dual-color silver in situ hybridization (dc-SISH) technique as an alternative to FISH. MATERIALS AND METHODS: A total of 40 invasive breast carcinoma cases were assessed for HER2 gene amplification by FISH and dual- color SISH. RESULTS: Significant correlation was found in the HER2 expression results obtained with the two approaches (p=0.001, p<0.05). The concordance rate was 92.3%. CONCLUSIONS: Foutine practical use of the dc-SISH method, which is much easier to apply, score, and evaluate, has many advantages. HER2 and CEN17 status can be evaluated simultaneously with the newly developed "Dual-Color Probe". All these specifications and the reliable results obtained support the widespread use of SISH technique in clinical practice.

Significance of bone marrow reticulin fibrosis in chronic lymphocytic leukemia at diagnosis: a study of 176 patients with prognostic implications.

BACKGROUND: Bone marrow (BM) biopsies from patients with chronic lymphocytic leukemia (CLL) may show reticulin fibrosis at diagnosis, but its significance remains unclear. This study sought to assess the prognostic impact of BM reticulin fibrosis in patients with previously untreated CLL. METHODS: Data was reviewed from untreated CLL patients in the national Israel CLL database, followed during 1987 to 2012. All bone marrow biopsies were graded for reticulin fibrosis using a modified scoring system containing 4 grades (0-3), based on the European consensus report. Grade of reticulin fibrosis was correlated with overall survival (OS), outcome, and a number of well-recognized prognostic factors for CLL. RESULTS: The final cohort included 176 patients (122 males and 51 females). Median age was 63 years (range, 32-86 years) and the 5-year OS was 77.1%. Grade of BM reticulin fibrosis correlated with OS (P < .0001) and mortality (P = .001), and separated patients into 2 groups with different survival curves. Advanced reticulin fibrosis (grades 2-3) was associated with thrombocytopenia (platelet counts of < 100,000/mm(3) ) (P = .025), anemia (P = .018), elevated ß2-microglobulin < 4000 µg/mL (P = .048), and the presence of 11q deletion (P = .0015). CONCLUSIONS: There was a significant correlation between poor survival and grade of BM reticulin fibrosis. This staining procedure is easy to perform and can readily be added routinely when examining BM biopsies in CLL, because the findings do have prognostic implications.

Significance of AgNORs and ki-67 proliferative markers in differential diagnosis of thyroid lesions.

We aimed to assess the utility of quantitative analysis of AgNORs and Ki67 labeling index (LI) in the differential diagnosis of different thyroid lesions. This study included: 25 papillary carcinomas, 7 follicular carcinomas, 21 follicular adenomas and 27 nodular goiters. Using a semiautomatic image analysis system, Ag NORs parameters were measured and calculated including: total area of AgNORs, mean Ag NOR number in nuclei, nuclear area, mean area of AgNOR dots per each nucleus, number of central and marginal AgNOR dots, and the relative ratio of total area of AgNOR dots/total area of nucleus. Ki67 immunostaining was performed and the LI was determined. There was a significant difference between groups of thyroid lesions regarding total area of AgNORs, Ag NOR number and number of marginal Ag NOR dots. According to receiver operating characteristic curve, Ag NORs number =2.91 and marginal Ag NORs = 2.67 were useful cut off values above which follicular carcinoma can be diagnosed with 100 % sensitivity, 79 % specificity, 76 % PPV, 100 % NPV and 85 % diagnostic accuracy for both parameters. Mean Ki67 LI in our study was 14.12 ± 2.29, 61.42 ± 3.77, 34.90 ± 3.49 and 18.60 ± 1.96 for papillary carcinoma, follicular carcinoma, follicular adenoma and nodular goiter respectively. Ki67 LI showed statistically significant difference between follicular carcinoma and follicular adenoma (p = 0.026) and between papillary carcinoma and follicular adenoma (p = 0.007). Quantification of Ag NORs and Ki67 LI could be used as helpful ancillary methods in the differentiation between different thyroid lesions.

Impaired c-Fos and polo-like kinase 2 induction in the limbic system of fear-conditioned α-synuclein transgenic mice.

α-Synuclein (αSYN) is genetically and neuropathologically linked to a spectrum of neurodegenerative diseases including Parkinson's disease, dementia with Lewy bodies, and related disorders. Cognitive impairment is recapitulated in several αSYN transgenic mouse lines. However, the mechanisms of dysfunction in affected neurons are largely unknown. Here we measured neuronal activity induced gene products in the limbic system of αSYN transgenic mice upon fear conditioning (FC). Induction of the synaptic plasticity marker c-Fos was significantly reduced in the amygdala and hippocampus of (Thy1)-h[A30P]αSYN transgenic mice in an age-dependent manner. Similarly, the neuronal activity inducible polo-like kinase 2 (Plk2) that can phosphorylate αSYN at the pathological site serine-129 was up-regulated in both brain regions upon FC. Plk2 inductions were also significantly impaired in aged (Thy1)-h[A30P]αSYN transgenic mice, both in the amygdala and hippocampus. Plk2 inductions in the amygdala after FC were paralleled by a small but significant increase in the number of neuronal cell bodies immunopositive for serine-129 phosphorylated αSYN in young but not aged (Thy1)-h[A30P]αSYN transgenic mice. In addition, we observed in the aged hippocampus a distinct type of apparently unmodified transgenic αSYN profiles resembling synaptic accumulations of αSYN. Thus, the cognitive decline observed in aged αSYN transgenic mice might be due to impairment of neurotransmission and synaptic plasticity in the limbic system by distinct αSYN species.

Identification of protein complexes in Escherichia coli using sequential peptide affinity purification in combination with tandem mass spectrometry.

Since most cellular processes are mediated by macromolecular assemblies, the systematic identification of protein-protein interactions (PPI) and the identification of the subunit composition of multi-protein complexes can provide insight into gene function and enhance understanding of biological systems(1, 2). Physical interactions can be mapped with high confidence vialarge-scale isolation and characterization of endogenous protein complexes under near-physiological conditions based on affinity purification of chromosomally-tagged proteins in combination with mass spectrometry (APMS). This approach has been successfully applied in evolutionarily diverse organisms, including yeast, flies, worms, mammalian cells, and bacteria(1-6). In particular, we have generated a carboxy-terminal Sequential Peptide Affinity (SPA) dual tagging system for affinity-purifying native protein complexes from cultured gram-negative Escherichia coli, using genetically-tractable host laboratory strains that are well-suited for genome-wide investigations of the fundamental biology and conserved processes of prokaryotes(1, 2, 7). Our SPA-tagging system is analogous to the tandem affinity purification method developed originally for yeast(8, 9), and consists of a calmodulin binding peptide (CBP) followed by the cleavage site for the highly specific tobacco etch virus (TEV) protease and three copies of the FLAG epitope (3X FLAG), allowing for two consecutive rounds of affinity enrichment. After cassette amplification, sequence-specific linear PCR products encoding the SPA-tag and a selectable marker are integrated and expressed in frame as carboxy-terminal fusions in a DY330 background that is induced to transiently express a highly efficient heterologous bacteriophage lambda recombination system(10). Subsequent dual-step purification using calmodulin and anti-FLAG affinity beads enables the highly selective and efficient recovery of even low abundance protein complexes from large-scale cultures. Tandem mass spectrometry is then used to identify the stably co-purifying proteins with high sensitivity (low nanogram detection limits). Here, we describe detailed step-by-step procedures we commonly use for systematic protein tagging, purification and mass spectrometry-based analysis of soluble protein complexes from E. coli, which can be scaled up and potentially tailored to other bacterial species, including certain opportunistic pathogens that are amenable to recombineering. The resulting physical interactions can often reveal interesting unexpected components and connections suggesting novel mechanistic links. Integration of the PPI data with alternate molecular association data such as genetic (gene-gene) interactions and genomic-context (GC) predictions can facilitate elucidation of the global molecular organization of multi-protein complexes within biological pathways. The networks generated for E. coli can be used to gain insight into the functional architecture of orthologous gene products in other microbes for which functional annotations are currently lacking.

Human milk sIgA molecules contain various combinations of different antigen-binding sites resulting in a multiple binding specificity of antibodies and enzymatic activities of abzymes.

In the classic paradigm, immunoglobulins are monospecific molecules that have stable structures and two or more identical antigen-binding sites. However, we show here for the first time that the sIgA pool of human milk contains, depending on the donor, only 35±5% λ-sIgAs, 48±7% κ-sIgAs, and 17±4% of chimeric λ-κ-sIgAs. sIgA preparations contained no traces of canonical enzymes. However, all sIgA fractions eluted from several specific affinity sorbents under the conditions destroying even strong immune complexes demonstrated high catalytic activities in hydrolysis of ATP, DNA, and oligosaccharides, and phosphorylation of proteins, lipids, and oligosaccharides. Sequential re-chromatographies of the sIgA fractions with high affinity to one affinity sorbents on the second, third and then fourth affinity sorbents bearing other immobilized antigens led to the distribution of Abs and all catalytic activities all over the profiles of these chromatographies; in all cases some fractions eluted from affinity sorbents only under the conditions destroying strong immune complexes. In vitro, only an addition of reduced glutathione and milk plasma containing no Abs to two sIgA fractions with different affinity for DNA-cellulose led to a transition of up to 11-20% of Ab from one fraction to the other. Our data are indicative of the possibility of half-molecule exchange between different IgA and sIgA molecules. In addition, it cannot be excluded that during the penetration of IgAs through the specific milk barrier, the secretory component (S) and the join chain (J) can combine molecules of dimeric H(2)L(2) λ-IgAs and κ-IgAs against different antigens forming many different variants of H(4)L(4)SJ sIgA molecules. Therefore, some chimeric molecules of sIgA can contain from two to four HL-fragments to various antigens interacting with high affinity with different sorbents and catalyzing various chemical reactions. Our data essentially expand the ideas concerning explanation of the phenomenon of polyspecificity and cross-reactivity of Abs.