Expression of AgNOR in histopathologically diagnosed gastric carcinoma patients

Background: Worldwide, gastric cancer is the second leading cause of cancer-related fatalities, after lung cancer. Identifying stomach cancer without relying entirely on histopathology is critical. The Silver-stained nucleolar organizer regions (AgNOR's) reflect the aggressiveness of the tumor, according to the study. To establish the effectiveness of these approaches in detecting stomach cancer, the present study was done in order to test their efficacy. The aim of the study was to observe expression of AgNOR in histopathologically diagnosed gastric carcinoma patients.Methods: This cross-sectional analytical study was carried out in the department of pathology, Sir Salimullah Medical College, Dhaka, Bangladesh from July 2017 to June 2019. A total of 60 adults who were histopathologically diagnosed patients with gastric carcinoma in gastric endoscopic biopsies and resected samples.Results: More than one-third of the patients (38.3%) belonged to the age group of 61-70 years. The age range of the participants was 40-82. 55% were male and 45% were female, 63.3% of the cancers were in the pylorus region, 33.3% were in the body and 3.3% were in the cardiac end. 80% of the GC were intestinal type and 20% were of diffuse type. 50% of the cancers were moderately differentiated, 36.67% were poorly differentiated, and 13.33% were well differentiated. The association between histopathological grading of gastric carcinoma and AgNOR was statistically significant.Conclusions: The growth of the tumor is highly variable. The AgNOR stain is also a good marker to detect the proliferation of tumor cells.

May Argyrophilic Nucleolar Organizer Regions Be Used as a Biomarker for the Detection of the Degree of Ischemic Damage Instead of Tunel in Testicular Torsion?

Background and Objectives: It is of great importance to obtain information about the severity of ischemic damage and duration of testicular torsion for an effective treatment strategy. Nucleolar-organizing regions (NORs) are sites of the ribosomal genes composed of ribosomal DNA and proteins. Post-silver staining NORs are termed “AgNOR”. Since AgNORs clearly reveals the self-renewal potential of cells damaged in ischemic events, we performed the current study. Materials and Methods: The study was carried out in four groups as control, sham, early, and late T/D. In the surgical groups, testes were corrected after a 4-h ischemia period. Testicular tissue samples were taken on the third day after detorsion in group 1, 2, 3, and on the tenth day after detorsion in group 4. TUNEL and silver stainings were applied to all samples. Results: The differences were significant among the groups for both mean AgNOR number and total AgNOR area/total nuclear area (TAA/TNA). Moreover, the differences between control and early torsion-detorsion (T/D), between control and late T/D, between sham and early T/D, between sham and late T/D, and between early T/D and late were statistically significant for AgNOR amount. Furthermore, statistically significant differences among the groups for an average number of apoptotic cells per tubule and the percentage of apoptotic tubule values were detected. Discussion: The apoptotic index gives the ratio of cells that are damaged and will die in a programmed way and cells that remain intact, rather than show the viability of the returning testicle. However, by measuring cells that regenerate with AgNOR, we can show not only those that survive but also cells that can repair themselves. Conclusion: AgNOR proteins are usable for the early observation of ischemic injury levels. The amount of AgNOR protein can enlighten us about the extent of testicular damage after T/D treatment. It may also help the physician in the development of effective treatment strategies for cases.

Effect of 50-Hz Magnetic Fields on Argyrophilic Nucleolar Organizer Regions in Bone Marrow Cells

Background: Exposure to an increasing amount of extremely low-frequency magnetic fields (MFs) causes some adverse effects. Considering a direct association between the sizes and numbers of argyrophilic nucleolar organizer regions (AgNORs) and cell proliferation, this study was conducted to evaluate the effect of 50-Hz MFs on the AgNORs of bone marrow (BM) cells. Methods: Eighty male rats were randomly divided into four exposed groups and one control group. The exposed groups received 50-Hz MFs with magnetic flux densities of 1, 100, 500, and 2000 µT two hours a day for two months. BM cells were aspirated from sacrificed rats’ femoral bones, smeared on glass slides, and then stained with silver nitrate for AgNORs. The area (AA), length (AL), and number (AN) of AgNORs were calculated by a microscope equipped with a camera and Scion Image software in 100 BM cells of each rat. The mean of AA, AL, and AN was computed for each group. Results: AA, AL, and AN significantly reduced in the 1 µT group compared with 2000 µT and control groups. Eventually, there was a nonlinear relationship between the effect of 50-Hz MFs and magnetic flux densities. Conclusion: Overall, 50-Hz MFs with a magnetic flux density of 1 µT reduced AgNORs in BM cells. However, 100, 500, and 2000 µT did not affect AgNORs. Therefore, 50-Hz MFs with low density may suppress BM cell proliferation.

First Report on Nucleolar Organizer Regions (NORs) Polymorphism and Constitutive Heterochromatin of Moonlight Gourami, Trichopodus microlepis (Perciformes, Osphronemidae)

Nucleolar organizer regions (NORs) polymorphism, constitutive heterochromatin and chromosomal analysis of Moonlight gourami, Trichopodus microlepis in Thailand were firstly reported. Specimens were collected from the Chao Phraya and Mekong Basins, Thailand. The mitotic chromosomes were directly prepared from kidney tissues of ten males and ten females. Conventional staining, Ag-NOR banding and C- banding techniques were applied to stain the chromosomes. The results shown that the diploid chromosome number of T. microlepis was 2n=46 and the fundamental number (NF) was 46 in both males and females. The karyotype consisted of 46 telocentric chromosomes classifying as 14 large and 32 medium. No heteromorphic sex chromosome was observed in T. microlepis. The results also exhibited that the interstitial nucleolar organizer regions (NORs) were clearly observed at the long arm of the chromosome pair 7. This is the first report on NORs polymorphism in T. microlepis that a heteromorphic NOR type in one female had a single NOR-bearing chromosome of the chromosome pair 7, whereas 10 males and nine females had two NOR-bearing chromosomes of the chromosome pair 7 with a homomorphic NOR type. Constitutive heterochromatins located at all centromeres of all chromosome pairs. The karyotype formula of T. microlepis is 2n (46) = Lt14 + Mt32.

Avaliação quantitativa da expressão da proteína PCNA e das AgNORs em ameloblastomas

In order to assess the proliferative behaviour of the ameloblastoma epithelium nine cases of this neoplasm were retrieved from the files of the Oral Pathology Service laboratory of Rio Grande do Sul Federal University School of Dentistry. Two proliferation marker techniques were employed: the AgNor - argyrophilic nucleolar organizer regions staining and the proliferation cell nuclear antigen (PCNA) immunohistochemical assessment technique. Each case was submitted to a quantitative and comparative statistical analysis of the results obtained for the two techniques. The conclusion arrived at shows ameloblastoma presenting benign behavior, an average AgNOR index of 1.612, and a PCNA proteindependent proliferative activity with average immunoreactivity of 51.61%. The histological patterns analyses of the neoplastic epithelial component demonstrates that cells resembling pre-ameloblasts have obtained figures statistically higher to those obtained for cells resembling the stellate reticulum of the enamel organ, in both techniques employed. Therefore, it might be inferred that cells resembling pre-ameloblasts hold the proliferative potential of ameloblastomas and are probably responsible for the growth characteristics and infiltrative ability of this tumour.

A comparative chromosome study on five Minnow fishes (Cyprinidae, Cypriniformes) in Thailand

The cytogenetic comparisons of five Minnow species from Thailand were presented here, i.e., Devario regina, D. laoensis, Rasbora paviana, R. aurotaenia and Esomus metalicus. The mitotic chromosomes were prepared directly from renal cells. Conventional staining and Ag-NOR banding techniques were applied to stain the chromosomes. The results revealed that all Minnow fishes studied possessed the same diploid chromosome number (2n) as 50 chromosomes. The fundamental numbers (NF) of D. laoensis, D. regina, R. paviana, R. aurotaenia and E. metalicus are 100, 100, 98, 98, and 98 respectively. Their karyotypes composing of metacentrics-submetacentrics-acrocentrics-telocentrics were as follows: 6-12-32-0 in D. regina, 6-10-34-0 in D. laoensis, 8-16-24-2 in R. paviana, 8-16-24-2 in R. aurotaenia and 8-10-30-2 in E. metalicus. The Ag-NOR banding technique provides the nucleolar organizer regions (NORs) at subtelomeric region of the short arm chromosome in the a submetacentric or acrocentric chromosomes that are located differently in the different chromosome pairs among species.

First report of karyological analysis and heteromorphic nucleolar organizer region of Black Surgeonfish (Acanthurus gahhm, Acanthuridae) in Thailand

This research was the first report on karyological analysis and heteromorphic nucleolar organizer region of black surgeonfish (Acanthurus gahhm, Acanthuridae) in Thailand. The 10 male and 10 female specimens were collected from Phuket Marine Biological Center, and Phang Nga Coastal Research and Development Center, Andaman Sea, Thailand. Mitotic chromosomes were directly prepared from gill and kidney tissues. The chromosomes were stained by conventional Giemsa staining and Ag-NOR banding techniques. Results showed that the diploid chromosomes number of A. gahhm was 2n=48, the fundamental numbers (NF) was 54 in both male and female. The karyotype consist of 6 large acrocentric, 20 large telocentric, 18 medium telocentric and 4 small telocentric chromosomes. None of strange size chromosomes related to sex was found. The heteromorphic nucleolar organizer regions (NORs) were observed on telomeric short arm of first acrocentric which can defined as 1a1b. There is NOR in 1a and not in 1b. The karyotype formula of black surgeon fish was as follows: 2n (48) = La6+Lt20+Mt18+St4

Polymorphism of nucleolar organizer regions in different Ukrainian cattle breeds

Aim. To study the activity of nucleolar organizer regions (NORs) in different Ukrainian cattle breeds in terms of their apparent activity status in silver stain and possible relation with milk productivity. Methods. Chromosome prepara- tions using lymphocytes from the peripheral blood of 90 cows of different breeds were used in the study. NOR activity was determined by visual evaluation of concentrations of silver precipitation on NORs in individual chromosomes. A 50 % silver nitrate solution was used to stain chromosome preparations. NORs were detected as dark spots on telomeres of the corresponding chromosomes. Results. The cytological analysis of chromosome preparations from lymphocytes of first lactation cows detected NOR polymorphism in Ukrainian Red-and-Motley dairy cattle (URM), Ukrainian Black-and-White dairy breed (UBW), and hybrid cows, obtained by crossing Ukrainian Red-and-Motley dairy breed and Montbeliarde bulls (URM × M). First lactation cows of URM and UBM had higher or the same inci- dence of cells with four (29.8 and 30 %) and five (17.1 and 19.5 %) NORs, while in URM × M cows the incidence of cells with the same number of NORs was almost twice lower; cells with 7 and 8 NORs exceeded a similar index for other investigated breeds almost twice (2.5 against 4.5 % and 2.0 against 4.2 %). The highest level of chromosomal aberrations (CA) was observed in the group of animals with medium number (2 to 3 NORs per cell), and the lowest – in the group with a high number of NORs (from 6 to 7) with a reliable intergroup difference (p < 0.01). NOR activity was the highest in the group of animals of local origin (URM × M) with a milk yield over 7,000 kg in 305 days of the first lactation and the lowest in the UBW cows with a milk yield of 4–5,000 kg during the first lactation. Conclusions. We determined the differences in the activity of nucleolar organizers between the investigated groups of cows of dairy breed. URM × M hybrids reliably (р ≤ 0.05) exceeded dairy UBW cows by this index. No statistically significant different was found between other investigated groups of animals by this trait. Higher dairy productivity was found in the animals with higher frequency of NORs in the chromosomes of metaphase cells. In our opinion, the number of active NORs demonstrates relative variability between their number and the rate of protein synthesis, required to implement the productivity traits of the investigated animals.

CORRELATION OF BIOPSY AND AgNOR COUNTS IN PREMALIGNANT AND MALIGNANT LESIONS OF CERVIX

Background- Cervical cancer is the commonest cancer among women in developing countries. Screening methods like cervical cytology has brought down the incidence of cervical cancer. AgNOR represents Nucleolar organizer regions stained with silver and are related to cell proliferation rate and tumor malignant potential. The present study was aimed at evaluating the diagnostic role of AgNOR in cervical carcinogenesis. Material and Methods- The present study was conducted in the Pathology department of Gajra Raja Medical College, Gwalior from January 2019 to May 2020 on 500 patients who attended the Gynae OPD. Women of suspected cervical pathology and who underwent Pap smear test followed by subsequent biopsies were included. Results- AgNOR count in chronic cervicitis was 2.72±0.32, in CIN I was 4.02±0.38, in CIN II was 5.47±0.21 in CIN III was 5.59±0.18, in Well differentiated KSCC was 6.48±0.40 and in adenocarcinoma was 6.93±0.21. The study showed that the mean AgNOR count per nucleus was signicantly higher in CIN and malignant cervical lesions. Conclusion- AgNOR count is reproducible, simple, efcient and inexpensive method which can be used as an adjunct to histopathology and cytology especially in differentiating doubtful cases of CIN.