• Title/Summary/Keyword: De-differentiation

Search Result 103, Processing Time 0.023 seconds

Relationship between the nucleolar cycle and chromatoid body formation in the spermatogenesis of $Phrynops$ $geoffroanus$ (Reptilia Testudines)

  • Peruquetti, Rita L.;Taboga, Sebastiao R.;Cabral, Silvia R.;De Oliveira, Classius;Azeredo-Oliveira, Maria T.
    • Animal cells and systems
    • /
    • v.16 no.2
    • /
    • pp.104-113
    • /
    • 2012
  • The nucleolus is a distinct nuclear territory involved in the compartmentalization of nuclear functions. There is some evidence of a relationship between nuclear fragmentation during spermatogenesis and chromatoid body (CB) formation. The CB is a typical cytoplasmic organelle of haploid germ cells, and is involved in RNA and protein accumulation for later germ-cell differentiation. The goal of this study was to qualitatively and quantitatively describe the nucleolar cycle during the spermatogenesis of $Phrynops$ $geoffroanus$ (Reptilia Testudines), and compare this nucleolar fragmentation with CB formation in this species through the use of cytochemical and ultrastructural analysis. Qualitative analysis showed a fragmentation of the nuclear material after pachytene of the first meiotic division in the primary spermatocytes. Quantitative analysis of the nucleolar cycle revealed a significant difference in the number of nucleoli and in the size of the nucleolus between spermatogonia and early spermatids. Using ultrastructural analysis, we recorded the beginning of the CB formation process in the cytoplasm of primary spermatocytes at the same time as when nuclear fragmentation occurs. In the cytoplasm of primary spermatocytes, the CB was observed in association with mitochondrial aggregates and the Golgi complex. In the cytoplasm of early spermatids, the CB was observed in association with lipid droplets. In conclusion, our data show that the nucleolus plays a role in the CB formation process. During spermatogenesis of $P.$ $geoffroanus$, the CB is involved in some important biological processes, including acrosome formation and mitochondrial migration to the spermatozoon tail and middle piece region.

Evidence of an Epigenetic Modification in Cell-cycle Arrest Caused by the Use of Ultra-highly-diluted Gonolobus Condurango Extract

  • Bishayee, Kausik;Sikdar, Sourav;Khuda-Bukhsh, Anisur Rahman
    • Journal of Pharmacopuncture
    • /
    • v.16 no.4
    • /
    • pp.7-13
    • /
    • 2013
  • Objectives: Whether the ultra-highly-diluted remedies used in homeopathy can effectively bring about modulations of gene expressions through acetylation/deacetylation of histones has not been explored. Therefore, in this study, we pointedly checked if the homeopathically-diluted anti-cancer remedy Condurango 30C (ethanolic extract of Gonolobus condurango diluted $10^{-60}$ times) was capable of arresting the cell cycles in cervical cancer cells HeLa by triggering an epigenetic modification through modulation of the activity of the key enzyme histone deacetylase 2 vis-a-vis the succussed alcohol (placebo) control. Methods: We checked the activity of different signal proteins (like $p21^{WAF}$, p53, Akt, STAT3) related to deacetylation, cell growth and differentiation by western blotting and analyzed cell-cycle arrest, if any, by fluorescence activated cell sorting. After viability assays had been performed with Condurango 30C and with a placebo, the activities of histone de-acetylase (HDAC) enzymes 1 and 2 were measured colorimetrically. Results: While Condurango 30C induced cytotoxicity in HeLa cells in vitro and reduced HDAC2 activity quite strikingly, it apparently did not alter the HDAC1 enzyme; the placebo had no or negligible cytotoxicity against HeLa cells and could not alter either the HDAC 1 or 2 activity. Data on $p21^{WAF}$, p53, Akt, and STAT3 activities and a cell-cycle analysis revealed a reduction in DNA synthesis and G1-phase cell-cycle arrest when Condurango 30C was used at a 2% dose. Conclusion: Condurango 30C appeared to trigger key epigenetic events of gene modulation in effectively combating cancer cells, which the placebo was unable to do.

A New Experiment or Institutional Subsumption? The Outcomes and Tasks of Contingent Worker Center for Korean Labor Movement (노동운동의 새로운 시도 혹은 제도적 포섭? 비정규노동센터의 성과와 과제)

  • Noh, Sung-Chul;Jung, Heung-Jun;Lee, Cheol
    • Korean Journal of Labor Studies
    • /
    • v.24 no.2
    • /
    • pp.137-179
    • /
    • 2018
  • To reduce labor market discrimination, there are lively discussions about the role of extant labor regime based on labor unions. It includes both the critical perspective on extant labor movement and the necessity of new actors for resolving discriminations within labor market. Among new actors, the present study focuses on contingent labor centers. Specifically, we have investigated on the development and identity of contingent labor centers as coalition of local government-labor organization. The core content of this study is to reconstruct the activities and strategies of contingent labor centers throughout the longitudinal approach. From many evidences, we can confirm that contingent labor centers have evolved via three phases such as differentiation, de- politicizing, and networks. This finding also provides insights about inside relationships between contingent labor centers and outside tensions between contingent labor center and extant labor organizations. We finally discuss on the theoretical implications of contingent labor center as new actor for contingent worker movement.

Immunohistochemical Array Analysis of Cemento-Ossifying Fibroma Exhibiting aneurysmal Cystic Changes (백악-골화섬유종에서 보이는 동맥류성 낭종변화의 면역조직화학염색 배열분석)

  • Lee, Sang Shin;Kim, Yeon Sook;Lee, Suk Keun
    • The Korean Journal of Oral and Maxillofacial Pathology
    • /
    • v.42 no.6
    • /
    • pp.189-198
    • /
    • 2018
  • A 31 years old female had been suffered from a bony swelling in right premolar region of the mandible for 12 years, recently grown rapidly. A fistula tract developed on the right anterior mandibular border, but the lesion was relatively asymptomatic. In the radiological examination, the tumor mass was irregularly mixed with radiolucent and radiopaque areas, forming multiple cystic spaces. Under the diagnosis of calcifying odontogenic cyst, the mandibular mass was resected and examined pathologically. After decalcification, the dissected tumor mass showed multiple small cystic spaces and calcifying fibrous tissue, mimicking calcifying odontogenic cyst or ameloblastoma. Histological observation showed many calcifying cementoid materials and ossifying trabeculae. The cystic spaces were turned out to be dilated vascular channels lined by endothelial cells, containing plasma fluid. However, the main lesion was diagnosed as cemento-ossifying fibroma (COF), and the atypical vascular channels were greatly dilated and gradually expanded the whole tumor mass. The present COF was examined through immunohistochemical (IHC) array, and investigated for tumor cell characteristics, exhibiting abnormal ossification and aneurysmal cystic changes. IHC array disclosed that the tumor cells grew progressively in the lack of apoptosis, and that they showed lower expression of RUNX2 than BMP-2, RANKL, and OPG, and increases of protein expression in $HIF-1{\alpha}$, VEGF-A, and CMG2. These data suggested that the reduced expression of RUNX2, osteoblast differentiation factor, be relevant to abnormal ossification of COF, and that the consistent expressions of angiogenesis factors be relevant to de novo angiogenesis in COF, subsequently resulted in aneurysmal cystic changes.

Cone-beam computed tomography texture analysis can help differentiate odontogenic and non-odontogenic maxillary sinusitis

  • Andre Luiz Ferreira Costa;Karolina Aparecida Castilho Fardim;Isabela Teixeira Ribeiro;Maria Aparecida Neves Jardini;Paulo Henrique Braz-Silva;Kaan Orhan;Sergio Lucio Pereira de Castro Lopes
    • Imaging Science in Dentistry
    • /
    • v.53 no.1
    • /
    • pp.43-51
    • /
    • 2023
  • Purpose: This study aimed to assess texture analysis(TA) of cone-beam computed tomography (CBCT) images as a quantitative tool for the differential diagnosis of odontogenic and non-odontogenic maxillary sinusitis(OS and NOS, respectively). Materials and Methods: CBCT images of 40 patients diagnosed with OS (N=20) and NOS (N=20) were evaluated. The gray level co-occurrence (GLCM) matrix parameters, and gray level run length matrix texture (GLRLM) parameters were extracted using manually placed regions of interest on lesion images. Seven texture parameters were calculated using GLCM and 4 parameters using GLRLM. The Mann-Whitney test was used for comparisons between the groups, and the Levene test was performed to confirm the homogeneity of variance (α=5%). Results: The results showed statistically significant differences(P<0.05) between the OS and NOS patients regarding 3 TA parameters. NOS patients presented higher values for contrast, while OS patients presented higher values for correlation and inverse difference moment. Greater textural homogeneity was observed in the OS patients than in the NOS patients, with statistically significant differences in standard deviations between the groups for correlation, sum of squares, sum of entropy, and entropy. Conclusion: TA enabled quantitative differentiation between OS and NOS on CBCT images by using the parameters of contrast, correlation, and inverse difference moment.

Comparison of media for a human peripheral blood mononuclear cell-based in vitro vaccine evaluation system

  • Shuran Gong;Putri Fajar;Jacqueline De Vries-Idema;Anke Huckriede
    • Clinical and Experimental Vaccine Research
    • /
    • v.12 no.4
    • /
    • pp.328-336
    • /
    • 2023
  • Purpose: Human peripheral blood mononuclear cell (PBMC)-based in vitro systems can be of great value in the development and assessment of vaccines but require the right medium for optimal performance of the different cell types present. Here, we compare three commonly used media for their capacity to support innate and adaptive immune responses evoked in PBMCs by Toll-like receptor (TLR) ligands and whole inactivated virus (WIV) influenza vaccine. Materials and Methods: Human PBMCs were cultured for different periods of time in Roswell Park Memorial Institute (RPMI), Dulbecco's minimal essential medium (DMEM), or Iscove's modified DMEM (IMDM) supplemented with 10% fetal calf serum. The viability of the cells was monitored and their responses to TLR ligands and WIV were assessed. Results: With increasing days of incubation, the viability of PBMCs cultured in RPMI or IMDM was slightly higher than that of cells cultured in DMEM. Upon exposure of the PBMCs to TLR ligands and WIV, RPMI was superior to the other two media in terms of supporting the expression of genes related to innate immunity, such as the TLR adaptor protein gene MyD88 (myeloid differentiation factor 88), the interferon (IFN)-stimulated genes MxA (myxovirus resistance protein 1) and ISG56 (interferon-stimulated gene 56), and the leukocyte recruitment chemokine gene MCP1 (monocyte chemoattractant protein-1). RPMI also performed best with regard to the activation of antigen-presenting cells. As for adaptive immunity, when stimulated with WIV, PBMCs cultured in RPMI or IMDM contained higher numbers of IFNγ-producing T cells and secreted more immunoglobulin G than PBMCs cultured in DMEM. Conclusion: Taken together, among the different media assessed, RPMI was identified as the optimal medium for a human PBMC-based in vitro vaccine evaluation system.

Surface characteristics of thermally treated titanium surfaces

  • Lee, Yang-Jin;Cui, De-Zhe;Jeon, Ha-Ra;Chung, Hyun-Ju;Park, Yeong-Joon;Kim, Ok-Su;Kim, Young-Joon
    • Journal of Periodontal and Implant Science
    • /
    • v.42 no.3
    • /
    • pp.81-87
    • /
    • 2012
  • Purpose: The characteristics of oxidized titanium (Ti) surfaces varied according to treatment conditions such as duration time and temperature. Thermal oxidation can change Ti surface characteristics, which affect many cellular responses such as cell adhesion, proliferation, and differentiation. Thus, this study was conducted to evaluate the surface characteristics and cell response of thermally treated Ti surfaces. Methods: The samples were divided into 4 groups. Control: machined smooth titanium (Ti-S) was untreated. Group I: Ti-S was treated in a furnace at $300^{\circ}C$ for 30 minutes. Group II: Ti-S was treated at $500^{\circ}C$ for 30 minutes. Group III: Ti-S was treated at $750^{\circ}C$ for 30 minutes. A scanning electron microscope, atomic force microscope, and X-ray diffraction were used to assess surface characteristics and chemical composition. The water contact angle and surface energy were measured to assess physical properties. Results: The titanium dioxide ($TiO_2$) thickness increased as the treatment temperature increased. Additional peaks belonging to rutile $TiO_2$ were only found in group III. The contact angle in group III was significantly lower than any of the other groups. The surface energy significantly increased as the treatment temperature increased, especially in group III. In the 3-(4,5-Dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide assay, after 24 hours of incubation, the assessment of cell viability showed that the optical density of the control had a higher tendency than any other group, but there was no significant difference. However, the alkaline phosphatase activity increased as the temperature increased, especially in group III. Conclusions: Consequently, the surface characteristics and biocompatibility increased as the temperature increased. This indicates that surface modification by thermal treatment could be another useful method for medical and dental implants.

Potential Therapeutic Targets for the Primary Gallbladder Carcinoma: Estrogen Receptors

  • Zhang, Ling-Qiang;Zhang, Xiu-De;Xu, Jia;Wan, Yong;Qu, Kai;Zhang, Jing-Yao;Wang, Zhi-Xin;Wei, Ji-Chao;Meng, Fan-Di;Tai, Ming-Hui;Zhou, Lei;Liu, Chang
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.4
    • /
    • pp.2185-2190
    • /
    • 2013
  • Gallbladder carcinoma, the most frequent malignant neoplasm of the biliary tract system, has always been considered to feature late clinical presentation and diagnosis, limited treatment options and an extremely poor prognosis. In recent years, while the incidence of gallbladder cancer has appeared to be on the increase, the available treatment methods have not greatly improved survival of the affected patients. Thus, exploring new therapeutic targets for this devastating disease is an urgent matter at present. Epidemical studies have demonstrated that the incidence of gallbladder carcinoma exhibits a distinct gender bias, affecting females two to three times more than males, pointing to crucial roles of estrogen. It is well known that estrogen acts on target tissues by binding to estrogen receptors (ERs), which are mainly divided into three subtypes, $ER{\alpha}$, $ER{\beta}$ and $ER{\gamma}$. $ER{\alpha}$ and $ER{\beta}$ appear to have overlapping but also unique even opposite biological effects. As important pathogenic mediators, ERs have been considered to relate to several kinds of tumors. In gallbladder carcinoma tissue, ERs have been shown to be positively expressed, and ERs expression levels are associated with differentiation and prognosis of this cancer. Nevertheless, the exact mechanisms of estrogen inducing growth of gallbladder carcinoma remain poorly understood. On the base of the current investigations, we deduce that estrogen participates in promotion of gallbladder carcinoma by influencing the formation of gallstones, stimulating angiogenesis, and promoting abnormal proliferation. Since ERs mediate the carcinogenic actions of estrogen in gallbladder, and therapy targeting ERs may provide new directions for gallbladder carcinoma. Therefore, it should be stressed that ERs are potential therapeutic targets for gallbladder carcinoma.

KAI1/CD82 and MRP1/CD9 Serve as Markers of Infiltration, Metastasis, and Prognosis in Laryngeal Squamous Cell Carcinomas

  • Zhang, Bing-Hui;Liu, Wei;Li, Liang;Lu, Jian-Guang;Sun, Ya-Nan;Jin, De-Jun;Xu, Xiu-Yu
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.6
    • /
    • pp.3521-3526
    • /
    • 2013
  • Objective: The current study explored the expression of KAI1/CD82 and MRP1/CD9 and its significance in laryngeal squamous cell carcinoma (LSCC). Methods: The expression levels of KAI1/CD82 and MRP1/CD9 in 100 LSCC tissue specimens, as well as in 30 para-LSCC non-carcinomatous tissue specimens randomly taken from the patients, were assessed using the quantitative polymerase chain reaction (Q-PCR) and immunohistochemistry and correlations with pathological parameters of LSCC and their influence on survival function were analyzed. Results: KAI1/CD82 and MRP1/CD9 showed basically consistent changes in both mRNA and protein expression. Their expression in the 30 LSCC specimens was significantly lower compared with that in the corresponding non-carcinous tissues (P < 0.01 or 0.05), notably correlating with TNM stage, differentiation degree, clinical stage, and lymphatic metastasis (P < 0.01 or 0.05), but not gender, age, and LSCC growth sites (P > 0.05). The median survival of patients with positive KAI1/CD82 and MRP1/CD9 protein expression was longer than that of patients with negative protein expression (P < 0.01 or 0.05). KAI1/CD82 protein expression negatively correlated with MRP1/CD9 protein expression in LSCC (${\chi}^2$= 31.25, P < 0.01). Conclusion: KAI1/CD82 and MRP1/CD9 may jointly participate in the development of LSCC. They may serve as the markers for judging the infiltration, metastasis, and prognosis of LSCC.

AN EXPERIMENTAL STUDY ON THE MICROHARDNESS OF DENTAL AMALGAMS (치과용 아말감의 미세경도에 관한 실험적연구)

  • Shin, Dong-Hoon
    • Restorative Dentistry and Endodontics
    • /
    • v.8 no.1
    • /
    • pp.89-96
    • /
    • 1982
  • The purpose of this study is to identify the phases of four different types, low-copper lathe cut (Type II, class 1) and spherical (Type II, class 2) amalgam alloys which are made by Caulk company and high copper Dispersalloy (Type II, class 3) made by Johnson & Johnson and Tytin (Type I, class 2) made by S.S. White and to determine the Vickers hardness number on the individual phase and four different types of dental amalgam. After each amalgam alloy and Hg measured exactly by the balance was triturated by the mechanical amalgamator (De Trey), the triturated mass was inserted into the cylindrical metal mold which was 4 mm in diameter and 12mm in height and was pressed by the Instron Universal Testing machine (Model 1125) at the speed of 1mm/minute with 143$kg/cm^2$ according to the A.D.A. Specification No. 1. The Specimen removed from the mold, mounted and stored in the room temperature for 7 days. The speciman was polished with the emery paper from #220 to #1200 and finally on the polishing cloth with 0.3 and 0.05 um $Al_2O_3$ powder suspended in water. And then each specimen was etched by Allan's method and washed with Sodium Bisulfinite for 30 seconds. Finally differentiation and metallography on each phase were obtained by using metallographical microscope (Versamet, Union) and microhardness was obtained by using microhardness tester (MVH-2, Torsee). The results were as follows: 1. In the low-copper amalgam, the ${\gamma}$, ${\gamma}_1$ and ${\gamma}_2$ phase were observed and in the high-copper amalgam, the ${\gamma}$, ${\gamma}_1$. ${\epsilon}$ and ${\eta}$ phases were observed but ${\gamma}_2$ phase was not observed. 2. Among the microhardness of each amalgam phase measured under pressing a vickers diamond indenter with 2.0gm load for 30 seconds, e phase has the highest V.H.N (314 ${\pm}$ 20), and in low-copper amalgam 12 phase has the lowest V.H.N. (29${\pm}$1) and ${\eta}$ phase which was observed in high-copper amalgam has 230${\pm}$13 V.H.N and this phase is considerd to contribute to strengthen the handness in amalgam. 3. The V.H.N. measured under pressing a Vickers diamond indenter with 300.0gm load for 30 seconds in low-copper amalgam was lower than that of high-copper amalgam.

  • PDF