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1.
Comput Methods Programs Biomed ; 242: 107788, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37738838

RESUMO

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.


Assuntos
Neoplasias Bucais , Região Organizadora do Nucléolo , Humanos , Coloração pela Prata/métodos , Neoplasias Bucais/diagnóstico por imagem , Redes Neurais de Computação
2.
J Oral Maxillofac Pathol ; 27(4): 735-743, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38304496

RESUMO

The primary goal of this systematic analysis is to determine the predictive significance of proliferative markers in surgical margins of patients with oral squamous cell carcinoma (OSCC). A thorough literature search was done on databases like MEDLINE/Pub-Med, Cochrane and Scopus libraries for similar studies until December 2022. All the relevant original research studies (retrospective and prospective) published in the literature assessing the predictive value of proliferative markers in surgical margins in OSCC were included. Seventeen studies with 1159 patients were included. The research included here used p53, p44/p42, proliferating cell nuclear antigen (PCNA), epidermal growth factor receptor (EGFR), Ki-67, Bcl2, Nibrin, AgNORs, Cyclin B1, Cornulin, ISG 15antibodies, MCM3 in OSCC. Four studies were done on oral premalignant lesions and OSCC. Among these studies, Ki-67 was the most accurate, followed by p53 (75%) and AgNORs, while PCNA had the least accuracy. To minimize the risk of bias panel of antibodies was suggested in most studies. For interobserver variability, analysis of variance and Chi-square test were used in most studies. The chance of recurrence rate was calculated using a log-rank test and a Kaplan-Meier curve. The significance of proliferative markers in surgical margins of OSCC has been emphasized in the present review. Future research should focus on selecting antibodies, preferably a panel, with a large sample size and extended follow-up.

3.
Asian Pac J Cancer Prev ; 23(6): 1983-1992, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35763640

RESUMO

OBJECTIVE: Nucleolar organizer regions (NORs) are DNA coils that transcribe to ribosomal RNA. The NOR-associated protein, termed argyrophilic NOR (AgNOR), was visible within the nucleus by staining with silver nitrate examination via the light microscope. AgNOR counting is a proliferation marker and may help in the diagnosis and prognosis of various neoplastic lesions. Aneuploidy (abnormal DNA content) can predict the progression, survival and prognosis of the tumors. The aim of this study was to evaluate the role of AgNORs, DNA ploidy status, and total S-phase fraction (TSPF) as prognostic parameters in malignant salivary gland tumors (MSGTs). METHODS: The current study is a retrospective study on a cohort of MSGTs (N=47), to assess AgNORs using Silver Nitrate stain, DNA index (DI), and TSPF using flow cytometry (FCM). Data including tumor size and site, lymphovascular invasion (LVI), lymph node metastasis (LNM) were collected. RESULTS: The AgNORs count was statistically significant with MSGT type. DI was found to have a significant association with tumor site, tumor size and MSGT type. In addition, TSPF was found to be significantly associated with LVI. A moderate positive correlation was noted between AgNORs count and TSPF. LNM, tumor site, high AgNORs and low DI were all associated with short disease-free survival (DFS) and poor overall survival (OS). CONCLUSION: The present study revealed that high AgNORs count, DNA aneuploidy and TSPF had a poor influence on MSGTs prognosis.


Assuntos
Região Organizadora do Nucléolo , Neoplasias das Glândulas Salivares , Aneuploidia , Humanos , Metástase Linfática , Região Organizadora do Nucléolo/genética , Ploidias , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/genética , Nitrato de Prata , Coloração pela Prata
4.
Cureus ; 12(11): e11738, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33269177

RESUMO

BACKGROUND:  Cancer burden can be reduced by early detection of early neoplastic changes applying suitable screening methods. This study aimed to assess the utility of nucleolar organizer regions (NORs) quantitation in early prediction of lung neoplastic transformation. METHODOLOGY: This study investigated 200 apparently healthy individuals categorized into two groups; smoking exposed individuals (N=100), and were categorized as cases, and smoking nonexposed (N=100), and were ascertained as controls. Sputum specimen was attained from each participant (paying all indispensable safety precautions and sample adequacy processes).  Results: Out of the 200 volunteers assessed in the present study, mean NORs counts of >2.00 were identified in 16/200(8%) of the study subjects. All 16/16(100%) cases were found with lung epithelial metaplasia (squamous metaplasia). Out of the 100 cases, mean NORs counts of >2.00 were identified in 16/100(16%), hence, all the controls were identified with mean NORs counts of <2.00. The risk of lung cellular proliferative changes associated with smoking exposure are odds ratio (OR) (95% confidence interval, CI) = 39.2485 (2.3199-664.0052), p = 0.0110, z statistic = 2.543. CONCLUSION: NORs count is a simple, specific, cost-effective, and reliable method that can give a quantitative measurement for the risk of lung neoplastic transformation. For at risk-population (tobacco users), it is recommended to perform the argyrophilic NORs (AgNORs) method beside sputum cytology.

5.
Cells ; 8(1)2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30650663

RESUMO

Multifaceted relations link ribosome biogenesis to cancer. Ribosome biogenesis takes place in the nucleolus. Clarifying the mechanisms involved in this nucleolar function and its relationship with cell proliferation: 1) allowed the understanding of the reasons for the nucleolar changes in cancer cells and their exploitation in tumor pathology, 2) defined the importance of the inhibition of ribosome biogenesis in cancer chemotherapy and 3) focused the attention on alterations of ribosome biogenesis in the pathogenesis of cancer. This review summarizes the research milestones regarding these relevant relationships between ribosome biogenesis and cancer. The structure and function of the nucleolus will also be briefly described.


Assuntos
Transformação Celular Neoplásica/metabolismo , Neoplasias/metabolismo , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Animais , Antineoplásicos/farmacologia , Nucléolo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Proteína Supressora de Tumor p53/metabolismo
6.
Neotrop. ichthyol ; 17(3): e190069, 2019. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1040664

RESUMO

Gymnorhamphichthys britskii is a Neotropical electric fish of family Rhamphichthyidae described from the Paraná-Paraguay system. This study reports the first karyotypic description of G. britskii collected from the upper Paraná river basin, which presented 2n=38 chromosomes, karyotype composed of 14 metacentric, 8 submetacentric, 2 subtelocentric and 14 acrocentric chromosomes, and fundamental number as 62 for both sexes. Heteromorphic sex chromosomes were absent. A single pair of nucleolar organizing regions (NORs) was detected in the submetacentric chromosome pair number 9 by silver staining and confirmed by the 18S rDNA probe. The 5S rDNA was located in a single chromosome pair. Heterochromatic regions were clearly observed in the short arms of the NOR-bearing chromosome pair and in the telomeric positions of most acrocentric chromosomes. Besides the present data are valuable to help in understanding karyotypic evolution in Rhamphichthyidae, data from NORs confirmed the tendency of this family in presenting simple NORs sites, similar to the other Gymnotiformes clades. Yet, the presence of a large heterochromatic block in the NOR-bearing chromosome can be used as cytogenetic markers for G. britskii, and that centric fusions appear to be an important mechanism in the karyotype evolution and differentiation among Gymnotiformes species.(AU)


Gymnorhamphichthys britskii é um peixe neotropical da família Rhamphichthyidae descrita no sistema Paraná-Paraguai. Este estudo relata a primeira descrição cariotípica de G. britskii coletado na bacia do alto rio Paraná, que apresentou 2n = 38 cromossomos, cariótipo composto por 14 metacêntricos, 8 submetacêntricos, 2 subtelocêntricos e 14 acrocêntricos, e número fundamental 62 para ambos sexos. Cromossomos sexuais heteromórficos estavam ausentes. Um único par de regiões organizadoras de nucléolos (RONs) foi detectado no par de cromossomos submetacêntricos número 9 por coloração com prata e confirmado pela sonda DNAr 18S. O DNAr 5S foi localizado em um único par cromossômico. Regiões heterocromáticas foram claramente observadas nos braços curtos do par de cromossomos que carrega a RON e nas posições teloméricas da maioria dos cromossomos acrocêntricos. Além dos dados presentes serem valiosos para auxiliar na compreensão da evolução cariotípica em Rhamphichthyidae, dados de RONs confirmaram a tendência desta família em apresentar sítios simples de RONs, semelhantes aos demais clados de Gymnotiformes. No entanto, a presença de um grande bloco heterocromático no cromossomo portador da RON, pode ser usado como marcador citogenético para G. britskii e as fusões cêntricas parecem ser um mecanismo importante na evolução e diferenciação cariotípica entre as espécies de Gymnotiformes.(AU)


Assuntos
Análise Citogenética/veterinária , Gimnotiformes/genética , Diploide , Cariótipo
7.
Braz. dent. j ; 29(3): 309-315, May-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951550

RESUMO

Abstract The aim of this study was to investigate salivary levels of TGFβ1 and proliferation/ maturation of epithelial mucosa cells in diabetic and hypertensive patients. Design: in this cross-sectional study, whole stimulated saliva and oral mucosa exfoliative cytology specimens were collected from 39 patients that were healthy (control, n=10) or presented history of arterial hypertension (HAS, n=9), diabetes mellitus (DM, n=10) or both (DM+HAS, n=10). Salivary flow rate (SFR), TGFβ1 level in saliva, AgNORs and the epithelial maturation were evaluated. Non-parametric Kruskal-Wallis test, followed by Dunn's multiple comparison post-test and the Spearman test correlation analysis were used. SFR showed a significant decreased in DM and DM+HAS (0.47±0.11 and 0.64±0.43 mL/min) when compared to control (1.4±0.38 mL/min). DM+HAS presented the highest value of TGFβ1 concentration (24.72±5.89 pg/mL). It was observed a positive correlation between TGFβ1 and glycaemia (R=0.6371; p<0.001) and a negative correlation between TGFβ1 and saliva (R=-0.6162; p<0.001) and glycaemia and SFR (R=-0.5654; P=0.001). AgNORs number and status of maturation of mucosa cells were similar for all conditions. DM and DM+HAS presented the lowest SFR, which correlated with increased TGFβ1 levels. Despite the higher TGFβ1 secretion it was not observed changes in the morphology or proliferation of epithelial cells when diabetes or hypertension was present.


Resumo O objetivo deste estudo foi investigar os níveis de TGFβ1 na saliva e a proliferação/maturação das células epiteliais da mucosa em paciente diabéticos e hipertensos. Neste estudo transversal, saliva estimulada e amostras de citologia exfoliativa de mucosa oral foram coletadas de um total de 39 pacientes que se apresentavam saudáveis (controle, n=10) ou com história de hipertensão arterial (HAS, n=9), diabetes mellitus (DM, n=10) ou ambos (DM+HAS, n=10). Taxa de fluxo salivar (SFR), níveis de TGFβ1 na saliva, AgNORs e maturação epitelial foram avaliados. Teste não-paramétrico de Kruskal-Wallis, seguido de comparação múltipla de Dunn e correlação de Spearman foram utilizados para as análises. SFR diminuiu significantemente em DM e DM+HAS (0,47±0,11 e 0,64±0,43 mL/min) quando comparado ao controle (1,4±0,38 mL/min). DM+HAS apresentou os maiores valores de concentração de TGFβ1 (24,72±5,89 pg/mL). Foi observada uma correlação positiva entre TGFβ1 e glicemia (R=0,6371; p<0,001) e uma correlação negativa entre TGFβ1 e saliva (R=-0,6162; p<0,001) e glicemia e SFR (R=-0,5654; p=0,001). Número de AgNORs e o padrão da maturação das células epiteliais foram similares entre os todos grupos. DM e DM+HAS apresentaram os menores valores de SFR, os quais foram correlacionados com o aumento nos níveis de TGFβ1. Apesar da maior secreção de TGFβ1, não foram observadas mudanças na morfologia ou proliferação das células epiteliais quando o paciente apresentava diabetes ou hipertensão.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Saliva/metabolismo , Diabetes Mellitus/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Hipertensão/metabolismo , Mucosa Bucal/metabolismo , Mucosa Bucal/patologia , Salivação , Taxa Secretória , Glicemia/metabolismo , Estudos de Casos e Controles , Estudos Transversais , Antígenos Nucleares , Diabetes Mellitus/patologia , Diabetes Mellitus/sangue , Hipertensão/patologia
8.
Neotrop. ichthyol ; 16(4): [e180066], out. 2018. mapas, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-964069

RESUMO

The present report represents the first cytogenetic description of Steindachneridion doceanum, great catfish which is currently at high extinction risk and it is listed as threatened on the red list of the Brazilian Ministry of the Environment, also are suggested karyotype relationships with other species of the same genus endemic from other river basins. The results revealed a diploid number of 2n = 56 and the karyotype composed of 18 metacentric, 20 submetacentric, 10 subtelocentric and 8 acrocentric chromosomes (NF = 104). The AgNORs and CMA3 signals were coincident in location occupying the short arm of an acrocentric chromosome pair (25th), in a secondary constriction. The 5S rDNA genes were localized on the short arms of one subtelocentric pair. C-banding revealed terminal blocks on the short arms on many chromosomes as well as terminal positive bands at the both ends of a submetacentric pair. C banding also revealed a large heterochromatic block in the secondary constriction (25th) region that was coincident with the AgNORs sites and CMA3+ bright bands. In spite S. doceanum represent an endemic taxon, in spite their geographic isolation their cytogenetic characteristics show similarities with other species of the genus.(AU)


O presente trabalho apresenta a primeira descrição citogenética de Steindachneridion doceanum, grande bagre que se encontra atualmente em alto risco de extinção e listado como ameaçado na lista vermelha do Ministério do Meio Ambiente, também sugere relações cariotípicas com outras espécies do mesmo gênero, endêmicas de outras bacias hidrográficas. Os resultados revelaram um número diplóide de 56 cromossomos e o cariótipo composto por 18 elementos metacêntricos, 20 submetacêntricos, 10 subtelocêntricos e 8 acrocêntricos (NF = 104). As marcações AgNORs e CMA3 foram coincidentes ocupando o braço curto de um par de cromossomos acrocêntricos (par 25), em uma constrição secundária. Os genes 5S rDNA foram detectados nos braços curtos de um par subtelocêntrico. A banda C revelou blocos terminais nos braços curtos em vários cromossomos, bem como blocos terminais nas duas extremidades de um par submetacêntrico. A banda C também evidenciou um grande bloco heterocromático na constrição secundária (par 25) coincidente com os sítios AgNORs e as bandas CMA3 positivas. Apesar de S. doceanum representar um táxon endêmico, suas características citogenéticas mostram semelhanças com outras espécies do gênero das quais se encontra geograficamente isolado.(AU)


Assuntos
Animais , Peixes-Gato/genética , Extinção Biológica , Cariótipo
9.
Arch Oral Biol ; 78: 94-99, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28222389

RESUMO

OBJECTIVE: Differentiation between the aggressive benign odontogenic tumors and their malignant counterparts is controversial and difficult. While flow cytometry (FCM) allowed DNA analysis in neoplasia, argyrophilic organizer regions (AgNORs) number and/or size in a nucleus are correlated with the ribosomal gene activity and therefore with cellular proliferation. The aim of this research was to study the diagnostic accuracy of FCM and AgNORs staining in differentiating between benign and malignant epithelial odontogenic tumors and to correlate between these two interventions. DESIGN: Sixteen benign cases [8 cases of ameloblastoma (AB) and 8 cases of keratocystic odontogenic tumor (KCOT)] and 13 malignant epithelial odontogenic tumors [8 cases of ameloblastic carcinoma (ABC) and 5 cases of clear cell odontogenic carcinoma(CCOC)] were included in the current study. For FCM analysis, a single cell suspension from Formalin fixed paraffin-embedded (FFPE) tumors was prepared according to a modified method described by Hedley (1989) and AgNORs staining were performed in accordance to the Ploton protocol (1986). Analysis of AgNORs was performed using both quantitative and qualitative methods. RESULTS: The work revealed that all the examined tumors were diploid, except for 40% of CCOC cases. The S-phase fraction (SPF) value, AgNORs count and AgNORs area/cell showed statistically significant difference on comparing benign and malignant groups. A weak positive correlation was observed between SPF and AgNORs count. CONCLUSION: The SPF value was considered to be more sensitive and specific in differentiation between aggressive benign and malignant epithelial odontogenic tumors in comparison to AgNORs counting.


Assuntos
Adenocarcinoma de Células Claras/patologia , Ameloblastoma/patologia , Citometria de Fluxo , Região Organizadora do Nucléolo/patologia , Tumores Odontogênicos/patologia , Humanos , Ploidias , Sensibilidade e Especificidade , Coloração e Rotulagem
10.
Bratisl Lek Listy ; 118(1): 61-65, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28127985

RESUMO

BACKGROUND: Curcumin is a polyphenol compound that has antioxidant, anticancer, anti-inflammatory, anti-hyperlipidemic and antimicrobial effects. Nucleolar-organizing regions are the sites of the gene on chromosomes. The present study was aimed to show the antitumoral effect of curcumin via AgNOR protein synthesis in Ehrlich's ascitic carcinoma (EAC) bearing mice. METHODS: Twenty three mice with EAC were randomly divided into 3 groups as positive control (n = 7), group 2 (n = 8) and 3 (n = 8) treated intraperitoneally with curcumin (25 mg/kg) and (50 mg/kg), respectively. The animals were sacrificed on Day 16, the solid tumors were removed out. Then, total AgNOR area/nuclear area (TAA/NA) and the mean AgNOR number were estimated for each mice. RESULT: Statistically significant differences were determined among the whole groups for TAA/NA ratio (p = 0.000), conversely mean AgNOR number (p = 0.361). When comparingthe two groups; while no difference was determined between the control and curcumin (25 mg/kg) groups (p = 0.061), the significant differences were detected between the control and curcumin (50 mg/kg) groups (p = 0.000) and between curcumin (25 mg/kg) and curcumin (50 mg/kg) groups (p = 0.000) for TAA/NA ratio. However, there was no significant difference for the mean AgNOR number in double comparison of the groups. CONCLUSIONS: The current study showed that curcumin had a crucial function against cancer development. Also, both AgNOR values might be used as biomarkers for detection of the most reliable therapeutic dose selection of cancer treatment (Tab. 3, Fig. 2, Ref. 27).


Assuntos
Antígenos Nucleares/biossíntese , Antígenos Nucleares/efeitos dos fármacos , Antineoplásicos/farmacologia , Carcinoma de Ehrlich/patologia , Curcumina/farmacologia , Animais , Feminino , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias
11.
J Photochem Photobiol B ; 167: 309-320, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28129629

RESUMO

Nanoparticle based drug delivery can rapidly improves the therapeutic potential of anti-cancer agents. The present study focused to evaluate the hepatoprotective activity of silver nanoparticles (AgNPs) synthesized using aqueous extracts of Andrographis paniculata leaves (ApAgNPs) and Semecarpus anacardium nuts (SaAgNPs) against diethylnitrosamine (DEN) induced liver cancer in mice model. The physico-chemical properties of synthesized AgNPs were characterized by Fourier transform infrared (FTIR) spectroscopy, Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction (SAED), X-ray Diffraction (XRD), Energy Dispersive X-ray (EDX) spectrum, Zeta potential and Dynamic Light Scattering (DLS) analysis. The surface plasmon resonance (SPR) absorption spectrum revealed a strong peak at 420nm for both SaAgNPs and ApAgNPs. FTIR results exhibited the presence of possible functional groups in the synthesized AgNPs. TEM analysis determined the hexagonal, and spherical shape of the synthesized silver nanoparticles. The XRD and SAED pattern confirmed the crystalline nature and crystalline size of the AgNPs. EDX result clearly showed strong silver signals in the range between 2 and 4keV. Zeta potential measurements indicated a sharp peak at -3.93 and -13.8mV for ApAgNPs and SaAgNPs, respectively. DLS measurement expressed the particle size distribution was 70 and 60nm for ApAgNPs and SaAgNPs, respectively. DEN (20mg/kg b.wt.) was subjected to induce liver cancer in mice for 8weeks and treated with biosynthesized silver nanoparticles. Interestingly, ApAgNPs and SaAgNPs treated DEN induced animal groups show a decreased level of aspartate amino transferase (AST), alanine amino transferase (ALT), serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT) activity and elevated level of catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST) and superoxide dismutase (SOD) activity over untreated DEN control animals group. Histopathological investigation reveals decreased fat accumulation, appearance of binucleated cells in nanoparticle treated animals and showed mere normal cells induced by DEN. Argyrophilic nucleolar organiser region (AgNORs) had a significant decrease in number of acidic proteins and mast cells assay showed decrease of metachromatic cells in nanoparticles treated animal groups over control. Present results strongly suggest that biomolecule coated silver nanoparticles exposure showed potential hepatoprotective effect against DEN induced liver cancer and could be used as an effective anticancer nanodrug.


Assuntos
Carcinógenos/toxicidade , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/prevenção & controle , Fígado/efeitos dos fármacos , Nanopartículas Metálicas , Prata/química , Animais , Carcinogênese , Cristalografia por Raios X , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/patologia , Masculino , Nanopartículas Metálicas/química , Camundongos , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Bratisl Lek Listy ; 117(6): 345-50, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27546367

RESUMO

BACKGROUND: Ischemia/reperfusion (I/R) injury is a complex event frequently observed in vascular surgery and can cause functional and structural cell damage. Nucleolar-organizing regions (NORs) are sites of the ribosomal genes located on chromosomes and can be stained with silver when they are active. Thus these proteins are named as argyrophilic-NOR (AgNOR)-associated proteins. We aimed to investigate any possible effects of renal I/R injury on the NOR protein synthesis and association between the AgNOR proteins amount and histopathological injuring score. METHODS: Nine female wistar-albino rats with weight of 200-250g were included into the study. The animals were randomly divided in two groups, a Control Group and an I/R Group. In I/R group, rats were subjected to 45 minutes of renal pedicle occlusion followed by 24 hours of reperfusion. In the control group no drug injections or ischemia reperfusion were performed in animals. Then histopathological injury score, mean AgNOR number and total AgNOR area/nuclear area (TAA/NA) were detected for each rat. RESULTS: The differences between control and I/R groups were significant for histopathological injury scores (p = 0.016). Also the differences between control group and I/R group were significant for mean AgNOR number (p = 0.000) and TAA/NA ratio (p = 0.000). Additionally, there was a positive correlation between TAA/NA ratio and histopathological injury score (r = 0.728; p = 0.026) and between mean AgNOR number and histopathological injury score (r = 0.670; p = 0.048). CONCLUSION: The detection of AgNOR proteins amount may be used as an indicator to obtain information about the cellular behaviour (self-protective mechanism of tubular epithelial cells) against I/R injury and cellular damage levels (Tab. 2, Fig. 4, Ref. 24).


Assuntos
Antígenos Nucleares/metabolismo , Rim/metabolismo , Região Organizadora do Nucléolo/metabolismo , Traumatismo por Reperfusão/genética , Animais , Feminino , Rim/irrigação sanguínea , Túbulos Renais/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar
13.
Bratisl Lek Listy ; 117(11): 653-658, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28125891

RESUMO

BACKGROUND: Rhamnetin is a flavonoid that has antioxidant, anti-inflammatory and anti-cancer effects. Nucleolar-organizing regions are the ribosomal genes region. We aimed to identify whether rhamnetin has an effect on cell proliferation and whether AgNOR proteins may be used for the detection of therapeutic benefits of the drugs and new metabolites, which have the potential of being used for cancer treatments. METHODS: Twenty-four mice with Ehrlich's ascites carcinoma (EAC) were randomly assigned to three main groups as positive control, and groups 2 and 3 treated intraperitoneally with rhamnetin (100 µg/kg and 200 µg/kg, respectively). All the animals were sacrificed on day16, 24 h after the last dose; the tumors, which developed at the site of injection were removed. Then, mean AgNOR number and total AgNOR area/nuclear area (TAA/NA) were detected for each mouse. RESULTS: Significant differences were detected among all groups for mean AgNOR number (p = 0.000) and TAA/NA ratio (p = 0.000). While the difference between positive control and Rhamnetin (100 µg/kg) group was not significant (p = 0.387), there are significant differences between positive control and Rhamnetin (200 µg/kg) group (p = 0.000) and between Rhamnetin (100 µg/kg) and Rhamnetin (200 µg/kg) groups (p = 0.000) for TAA/NA ratio. CONCLUSION: Rhamnetin has an important role in preventing cancer formation. Our study showed that mean AgNOR numbers and TAA/NA values may be used also as biomarkers for evaluating the success rate of the performed therapeutic strategy and accurate dose selection for the management of the disease (Tab. 3, Fig. 3, Ref. 45).


Assuntos
Antígenos Nucleares/biossíntese , Antígenos Nucleares/efeitos dos fármacos , Antineoplásicos/farmacologia , Carcinoma de Ehrlich/patologia , Carcinoma/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Quercetina/análogos & derivados , Animais , Antioxidantes , Biomarcadores , Relação Dose-Resposta a Droga , Humanos , Injeções Intraperitoneais , Camundongos , Quercetina/administração & dosagem , Quercetina/farmacologia , Distribuição Aleatória
14.
Biotech Histochem ; 91(2): 102-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26528580

RESUMO

We performed a hospital-based, unmatched case-control study to investigate the association between progressive stages of cervical neoplasia and digital analysis of cell proliferation by silver stained nucleolus organizer region associated proteins (AgNORs). We measured cell proliferation levels in the cervical epithelial cells of 10 women with low grade squamous intraepithelial lesions (LG-SIL), eight with high grade squamous intraepithelial lesions (HG-SIL), 11 with cervical cancer (CC) and eight with no cervical lesions (controls) using the AgNORs technique. Cell proliferation was measured by digital image analysis (DIA). DIA revealed increased total areas of AgNORs in HG-SIL and CC compared to LG-SIL and control patients. AgNORs with a kidney or cluster shape exhibited greater areas than those with a spherical or long shape. We propose a cut-off of 118 pixels to differentiate benign (control and LG-SIL) from malignant (HG-SIL and CC) lesions. DIA of AgNORs is a simple and inexpensive method for studying proliferation. The increased total area of AgNORs in malignant lesions provides information regarding cell behavior and may be related to cervical carcinogenesis; however, further validation studies are required to establish its usefulness in cytological analysis.


Assuntos
Antígenos Nucleares/metabolismo , Colo do Útero/metabolismo , Colo do Útero/patologia , Lesões Pré-Cancerosas/metabolismo , Neoplasias do Colo do Útero/metabolismo , Esfregaço Vaginal , Adulto , Estudos de Casos e Controles , Movimento Celular/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/patologia
15.
J Clin Pathol ; 69(1): 58-63, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26567317

RESUMO

AIMS: The nucleolus is an important cellular component involved in the biogenesis of the ribosome. This study was performed in order to validate the introduction of the argyrophilic nucleolar organiser region (AgNOR) stain technique, specific for the nucleoli detection, in neuropathological studies on sudden fetal and infant death. METHODS: In a wide set of fetuses and infants, aged from 27 gestational weeks to eight postnatal months and dead from both known and unknown causes, an in-depth neuropathological study usually applied at the Lino Rossi Research Center of the Milan University was implemented by the AgNOR method. RESULTS: Peculiar abnormalities of the nucleoli, as partial or total disruption above all in Purkinje cells (PCs), were exclusively found in victims of sudden fetal and infant death, and not in controls. The observed nucleolar alterations were frequently related to nicotine absorption in pregnancy. CONCLUSIONS: We conclude that these findings represent early hallmarks of PC degeneration, contributing to the pathophysiology of sudden perinatal death.


Assuntos
Antígenos Nucleares/análise , Morte Fetal , Região Organizadora do Nucléolo/química , Região Organizadora do Nucléolo/patologia , Células de Purkinje/química , Células de Purkinje/patologia , Morte Súbita do Lactente/patologia , Autopsia , Biomarcadores/análise , Regulação para Baixo , Feminino , Morte Fetal/etiologia , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Itália , Nicotina/efeitos adversos , Agonistas Nicotínicos/efeitos adversos , Região Organizadora do Nucléolo/efeitos dos fármacos , Valor Preditivo dos Testes , Gravidez , Células de Purkinje/efeitos dos fármacos , Reprodutibilidade dos Testes , Fatores de Risco , Fumar/efeitos adversos , Coloração e Rotulagem/métodos , Morte Súbita do Lactente/etiologia
16.
Biotech Histochem ; 90(3): 179-83, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25420891

RESUMO

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.


Assuntos
Adenoma/patologia , Carcinoma Papilar, Variante Folicular/patologia , Região Organizadora do Nucléolo/metabolismo , Biossíntese de Proteínas , Neoplasias da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Antígenos Nucleares/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Coloração pela Prata/métodos , Adulto Jovem
17.
J Clin Diagn Res ; 8(9): FC14-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25386440

RESUMO

AIMS: A comparative evaluation of proliferation activity in unicystic ameloblastoma (UA), multicystic ameloblastoma (MA) and keratocystic odontogenic tumor (KCOT) using silver staining technique. SETTINGS AND DESIGN: In the present study 21 histopathologically confirmed paraffin blocks,7 each of UA, MA and KCOT were selected and stained with silver nitrate. MATERIALS AND METHODS: For quantitative analysis, 100 cells were counted at 1000x magnification for AgNORs and the mean value was calculated. Qualitative analysis of AgNORs included normal (oval shaped) and abnormal groups (bean shaped) in the lesion. STATISTICAL ANALYSIS: The statistical analysis of data was done by a specialist statistician using two way ANOVA and multiple comparisons with Tukey's test in advanced excel. RESULTS: The AgNOR count was more in KCOT when compared to MA and UA with the pattern of distribution of AgNORs more in basal than in the parabasal layer in KCOT. The qualitative analysis showed small to large oval AgNOR's in KCOT and few clusters in MA whereas in UA irregular clusters were seen. CONCLUSION: This concludes the expediency of AgNOR staining in reflecting the high proliferation rate and a more aggressive behavior of KCOT in comparison to MA and UA which signifies requirement of a more hostile surgical approach in KCOT to avoid recurrences following different treatment modalities.

18.
Artigo em Inglês | MEDLINE | ID: mdl-25308441

RESUMO

Curcumin, the major yellow-orange pigment of turmeric derived from the rhizome of Curcuma longa, is a highly pleiotropic molecule with the potential to modulate inflammation, oxidative stress, cell survival, cell secretion, homeostasis and proliferation. Curcumin, at relatively high concentrations, was repeatedly reported to be a potent inducer of apoptosis in cancer cells and thus considered a promising anticancer agent. In the present paper, the effects of low concentrations of curcumin on human cervical cancer (HeLa) cells were studied. We found curcumin-mediated decrease in the cell number and viability, and increase in apoptotic events and superoxide level. In contrast to previously shown curcumin cytotoxicity toward different cervical cancer lines, we observed toxic effects when even as low as 1 µM concentration of curcumin was used. Curcumin was not genotoxic to HeLa cells. Because argyrophilic nucleolar protein (AgNOR protein) expression is elevated in malignant cells compared to normal cells reflecting the rapidity of cancer cell proliferation, we evaluated curcumin-associated changes in size (area) and number of silver deposits. We showed curcumin-induced decrease in AgNOR protein pools, which may be mediated by global DNA hypermethylation observed after low concentration curcumin treatment. In summary, we have shown for the first time that curcumin at low micromolar range may be effective against HeLa cells, which may have implications for curcumin-based treatment of cervical cancer in humans.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma/patologia , Curcumina/farmacologia , Região Organizadora do Nucléolo/efeitos dos fármacos , Neoplasias do Colo do Útero/patologia , Carcinoma/metabolismo , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Células HeLa , Humanos , Região Organizadora do Nucléolo/metabolismo , Neoplasias do Colo do Útero/metabolismo
19.
Prostate Int ; 2(2): 90-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25032195

RESUMO

PURPOSE: Prostatic carcinoma is a common and growing public health problem. Histological evaluation is fairly adequate for assessing tumor differentiation, but tumor proliferative activity is difficult to measure. Increasing evidence suggests that the factors controlling cell cycle progression also modulate the rate of ribosome biogenesis. Despite the influence of cyclin D1 and argyrophilic nuclear organizer region (AgNOR) on prostate cancer proliferation, few studies have evaluated the diagnostic importance of these markers. Therefore, the present study was carried out to analyze the diagnostic value of the proliferative markers cyclin D1 and AgNOR in various prostatic lesions and to determine whether any association or relation between these markers and different Gleason grades exists. METHODS: A total 50 cases of various prostatic lesions were studied. Tumor grade, AgNOR staining, and cyclin D1 expression were evaluated in all cases. Correlations between the intensity and differential localization of these markers and Gleason grades were evaluated. RESULTS: The mean AgNOR count in cases of prostatic intraepithelial neoplasia was high compared with cases of benign prostatic hyperplasia (BPH) but lower than that of carcinoma cases. The intensity of cyclin D1 expression was high in carcinoma. A total of 14 cases (46.67%) showed strong positivity. No significant correlation was found between the intensity of cyclin D1 expression, AgNOR count, and histologic grades of prostatic carcinoma, whereas a significant correlation was observed between intensity and percentage expression of cyclin D1 in BPH and carcinoma (P<0.01). Nuclear as well as cytoplasmic positivity was seen among various grades of carcinoma. CONCLUSIONS: AgNOR count and cyclin D1 may be helpful in distinguishing between BPH and carcinoma of the prostate but may not be used as reliable indicators of the grade of prostatic adenocarcinoma because of overlapping values in various grades. However, further studies on larger samples are required to elucidate the role of these markers in identification of premalignant lesions.

20.
Food Chem Toxicol ; 64: 200-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24296135

RESUMO

The aim of this study was to investigate the effect of Naringin on pre-neoplastic colorectal lesions induced by chemical carcinogen in rats. Female Wistar rats weighing 130.8±27.1 g received weekly one subcutaneous injection of 1,2-dimethylhydrazine (DMH, 20 mg/kg) for 10 weeks. The animals were divided into 5 groups with 6 animals in each group. Group 1: 0.9% saline; Group 2: DMH+0.9% saline; Group 3: DMH+Naringin (10 mg/kg); Group 4: DMH+Naringin (100 mg/kg); Group 5: DMH+Naringin (200 mg/kg). G2 and G3 showed a significant increase in ACF number, AgNOR/nucleus and mitosis compared to G1. G4 and G5 presented a significant reduction in these parameters compared to G2. The number of cells producing acidic and neutral mucins, red blood cells and the level of antioxidant minerals, such as copper, magnesium, selenium and zinc, were significantly reduced in G2 and G3, but similar in G4 and G5 compared to G1. Naringin, especially at 200 mg/kg, was effective in reducing the number of pre-neoplastic lesions in rats exposed to DMH. Some of these effects may be due to reduction in cellular proliferation and tissue levels of iron together with the recovery of antioxidant mineral levels induced by this flavonoid.


Assuntos
Neoplasias Colorretais/prevenção & controle , Flavanonas/farmacologia , Lesões Pré-Cancerosas/prevenção & controle , 1,2-Dimetilidrazina/toxicidade , Animais , Carcinógenos/toxicidade , Neoplasias Colorretais/induzido quimicamente , Feminino , Camundongos , Microscopia Eletrônica de Varredura , Lesões Pré-Cancerosas/induzido quimicamente , Ratos , Ratos Wistar
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