INFLUENCE OF ADRENALECTOMY AND HYPOPHYSECTOMY ON THE MITOTIC FREQUENCY OF SOME LABILE AND STABLE ORGANS OF THE RAT

2009 ◽  
Vol 47 (3) ◽  
pp. 291-296 ◽  
Author(s):  
Harald Teir ◽  
Irmeli Carpén
Keyword(s):  
Mitotic Frequency

Grading of Human Urothelial Carcinoma Based on Nuclear Atypia and Mitotic Frequency. II. Histological Description

1991 ◽  
Vol 145 (5) ◽  
pp. 972-976 ◽  
Author(s):  
Bengt-Erik Carbin ◽  
Peter Ekman ◽  
Hans Gustafson ◽  
Niels J. Christensen ◽  
Bengt Sandstedt ◽  
...  
Keyword(s):  
Urothelial Carcinoma ◽  
Nuclear Atypia ◽  
Mitotic Frequency

Interaction between gibberellin A4/7 and root-pruning on the reproductive and vegetative processes in Douglas-fir. IV. Effects on lateral bud development

1986 ◽  
Vol 16 (2) ◽  
pp. 211-221 ◽  
Author(s):  
J. N. Owens ◽  
J. E. Webber ◽  
S. D. Ross ◽  
R. P. Pharis
Keyword(s):  
Normal Development ◽  
Shoot Elongation ◽  
Douglas Fir ◽  
Root Pruning ◽  
Lateral Shoot ◽  
Bud Development ◽  
Lateral Bud ◽  
Mitotic Frequency ◽  
Bud Initiation ◽  
Vegetative Bud

The anatomy, mitotic frequency, size, and total insoluble carbohydrate histochemistry was studied in axillary apices from 9- and 10-year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) trees after cone induction treatments of root-pruning and (or) stem injections of a gibberellin A4 and A7 (GA4/7) mixture. Axillary buds were initiated at the time of root-pruning, but root-pruning treatment had no effect on axillary bud initiation. Axillary apices from control and gibberellin-treated trees were similar and followed the normal sequence of bud-scale initiation, differentiation, and leaf initiation (described previously) and no cone buds differentiated. Early development of axillary apices from root-pruned and root-pruned, gibberellin-treated trees was normal, but development became retarded near the time of vegetative bud flush. Retarded apices were small with low mitotic frequency and developed many features characteristics of latent apices. Retardation of axillary apices continued until mid-July when normal development resumed and apices differentiated into reproductive buds or vegetative buds, or became latent. The trees in which the greatest retardation of apical development occurred during lateral shoot elongation produced the most cone buds. These results are discussed in relation to hypotheses proposed to explain how cultural and gibberellin treatments affect cone induction in the Pinaceae.

scholarly journals Malignant Gastrointestinal Stromal Tumour with Metastasis

2015 ◽  
Vol 01 (01) ◽  
pp. 031-033
Author(s):  
Bhushita Lakhar ◽  
Nilesh Guru
Keyword(s):  
Gastrointestinal Stromal Tumors ◽  
Gastrointestinal Stromal Tumour ◽  
Anatomic Site ◽  
Stromal Tumors ◽  
Mesenchymal Neoplasms ◽  
Imaging Characteristics ◽  
The World ◽  
Mitotic Frequency ◽  
Malignant Lesions

AbstractGastrointestinal stromal tumors (GISTs) are the most usual mesenchymal neoplasms of the gastrointestinal tract. Ever since the classification of GIST as an entity distinct from leiomyoma's, leiomyosarcomas, etc., there has been an increased concern in defining their imaging characteristics. It is estimated that approximately 5000-10,000 people are affected per year by this tumor all over the world. Most GISTs are benign (70-80%). However, these tumors have a spectrum ranging from benign to malignant lesions, depending on its anatomic site, tumor size, and mitotic frequency. We report a case of multiple malignant GIST with metastasis into Liver.

Further analytical and experimental studies on the shoot apex of Helianthus annuus: variable activity in the central zone

1979 ◽  
Vol 57 (8) ◽  
pp. 971-980 ◽  
Author(s):  
E. L. Davis ◽  
Patricia Rennie ◽  
Taylor A. Steeves
Keyword(s):  
Helianthus Annuus ◽  
Mitotic Activity ◽  
Shoot Apex ◽  
Experimental Studies ◽  
Central Zone ◽  
Peripheral Zone ◽  
Intact Plants ◽  
Cast Doubt ◽  
Young Leaves ◽  
Mitotic Frequency

The cytologically distinctive central zone of the vegetative shoot apex of Helianthus annuus L. cv. Peredovic has a mitotic frequency considerably lower than that of the surrounding peripheral zone in intact plants. Apices excised and grown in culture for 5 days before being supplied with [H3]thymidine reveal a correspondingly low level of DNA synthesis in the central zone when autoradiographed. In similarly cultured apices, mitotic activity in the central zone is less than that recorded for intact plants. Labelling immediately after excision of the apex indicates that the central zone cells are activated by the operation and quiescence returns during the following 5 days. This activation is confirmed by mitotic counts 2 days after excision. The removal of only two young leaves from the apical buds of otherwise intact plants results in a comparable stimulation of mitotic activity in the central zone. These observations cast doubt upon the significance of mitotic activity in living shoot apices when these have been exposed for observation by removal of leaves. They also raise questions about the validity of labelling techniques which involve the partial dissection of the shoot apex.

scholarly journals P11.25 Assessing electrical properties of cells as predictive marker for patient-specific TTFields response and optimal frequency

2019 ◽  
Vol 21 (Supplement_3) ◽  
pp. iii48-iii48
Author(s):  
A Kinzel ◽  
E Zeevi ◽  
K Gotlib ◽  
C Wenger ◽  
A Naveh ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Cell Lines ◽  
Electric Fields ◽  
Predictive Marker ◽  
Membrane Capacitance ◽  
Patient Specific ◽  
Optimal Frequency ◽  
Tumor Treating Fields ◽  
Mitotic Frequency ◽  
Tumor Types

Abstract BACKGROUND Tumor treating fields (TTFields) are currently approved for the treatment of glioblastoma multiforme (GBM, using 200 kHz), and being tested in other tumor types such as non-small cell lung cancer and brain metastases occurring in this indication (LUNAR and METIS trials, using 150 kHz). Response to TTFields in cancer cells was empirically shown to be frequency-dependent specific for cell type; however, there are no markers available predicting optimal frequency or response in different cancer types or individual patients to date. There is evidence indicating electrical properties determine the optimal anti-mitotic frequency. This study analyzed the correlation of electrical properties of cells with their optimal TTFields frequency and sensitivity using the 3DEP reader (LabTech) to determine the electrical properties with the help of Dielectrophoresis (DEP) force. With this technique, cell movements within electric fields of different frequencies can by analyzed based on the physical effect of DEP, exercising a force on polarizable particles inside a non-homogeneous electric field. MATERIAL AND METHODS We used the 3DEP reader to obtain baseline properties (permittivity and conductivity) of 17 different cell lines of several tumor types. The resulting curves were analyzed by a 2-way ANOVA. Additionally, we determined the optimal frequency for maximum cytotoxic effect for each cell line using the inovitroTM system and eventually compared with the detected electrical properties. RESULTS We found cell lines with an optimal TTFields frequency of 150 kHz (corresponding to cells with a membrane capacitance in the lower range of the observed 3DEP curves, n=9) to possess significantly different (p<0.001) electrical properties from cells with an optimal TTFields frequency of 200 kHz (n=8). According to the curve differences in the lower frequency range, the measure of membrane capacitance served as a good predictor for TTFields response. CONCLUSION This study showed a correlation of cell membrane capacitance and optimal TTFields frequency and response. Our results provide a substantial rationale for further studies investigating the predictive potential of electrical properties of tumor cells as a measure for the optimal frequency and sensitivity to TTFields in individual patients.

The role of 20-hydroxyecdysone in stimulating epidermal mitoses during the laval-pupal transformation of the tobacco hornworm, Manduca sexta

Development ◽  
1987 ◽  
Vol 100 (2) ◽  
pp. 227-236 ◽  
Author(s):  
Y. Kato ◽  
L.M. Riddiford
Keyword(s):  
Mitotic Index ◽  
Manduca Sexta ◽  
Ploidy Level ◽  
Polyploid Cells ◽  
Mitotic Frequency ◽  
Mitotic Figures ◽  
Dorsal Epidermis

Temporal and regional changes in mitotic frequency were examined in the dorsal epidermis of the fourth and fifth abdominal segments of Manduca sexta during metamorphosis. Mitoses occurred only in the middle intrasegmental region, but not in the segmental margins. The mitoses began early on day 5 and rose to maximum of 2á6–4á6% about 10h later. When the integument from day 4 (wandering) larvae was cultured in Grace's medium containing 0.3 to 1μgml-1 20-hydroxyecdysone (20HE), the mitotic index increased with a peak at 18–24h exposure approximately equal to that found in situ. The level of 20HE required to initiate mitoses was similar to that found in vivo during the beginning of the prepupal rise in ecdysteroid and therefore is likely to be the signal for these cells to decrease their ploidy level of 4–32C to 2–8C at this time. The polyploid cells had larger mitotic figures and required a longer exposure to 20-hydroxyecdysone to initiate mitosis. Some multipolar mitotic figures were observed.

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