Cell distribution during mouse secondary palate closure

Development ◽  
1986 ◽  
Vol 96 (1) ◽  
pp. 111-130
Author(s):  
Linda L. Brinkley ◽  
Fred L. Bookstein

The patterns of distribution of both total mesenchymal cells and the ratios of [3H]thymidinelabelled to total cells were mapped during secondary palatal shelf reorientation in vivo and in vitro. Smoothed spatial averaging, a computer-assisted method which takes into account the positions of all cells across an entire histological section of the shelf, was employed. Changes in shelf cross-sectional area and cell size were also measured. Three shelf regions, anterior and posterior presumptive hard and presumptive soft palate, were studied at developmental stages which were 30, 24 and 18 h prior to expected in vivo elevation, after in vivo reorientation and during the course of in vitro reorientation. Region-specific patterns of cell distribution change with shelf reorientation. These changes were observable within 6 h. Increases in cell number by cell division may enhance some high local cell densities, but cannot account for decreases in cell density. Increase in cell size is not a factor in decreasing cell density, nor is cell death. Displacement of cells by expansion of the extracellular matrix may be involved.

2019 ◽  
Author(s):  
Ming-Kai Hsieh ◽  
Chia-Jung Wu ◽  
Xuan-Chun Su ◽  
Yi-Chen Chen ◽  
Tsung-Ting Tsai ◽  
...  

AbstractBackgroundCells, scaffolds, and factors are the triad of regenerative engineering; however, it is difficult to distinguish whether cells in the regenerative construct are from the seeded cells or host cells via the host blood supply. We performed a novel in vivo study to transplant enhanced green fluorescent pig mesenchymal stem cells (EGFP-pMSCs) into calvarial defect of DsRed pigs. The cell distribution and proportion were distinguished by the different fluorescent colors through the whole regenerative period.Method/ResultsEight adult domestic Ds-Red pigs were treated with five modalities: empty defects without scaffold (group 1); defects filled only with scaffold (group 2); defects filled with osteoinduction medium-loaded scaffold (group 3); defects filled with 5 × 103 cells/scaffold (group 4); and defects filled with 5 × 104 cells/scaffold (group 5). The in vitro cell distribution, morphology, osteogenic differentiation, and fluorescence images of groups 4 and 5 were analyzed. Two animals were sacrificed at 1, 2, 3, and 4 weeks after transplantation. The in vivo fluorescence imaging and quantification data showed that EGFP-pMSCs were represented in the scaffolds in groups 4 and 5 throughout the whole regenerative period. A higher seeded cell density resulted in more sustained seeded cells in bone regeneration compared to a lower seeded cell density. Host cells were recruited by seeded cells if enough space was available in the scaffold. Host cells in groups 1 to 3 did not change from the 1st week to 4th week, which indicates that the scaffold without seeded cells cannot recruit host cells even when enough space is available for cell ingrowth. The histological and immunohistochemical data showed that more cells were involved in osteogenesis in scaffolds with seeded cells.ConclusionOur in vivo results showed that more seeded cells recruit more host cells and that both cell types participate in osteogenesis. These results suggest that scaffolds without seeded cells may not be effective in bone transplantation.


2020 ◽  
Vol 20 (8) ◽  
pp. 1253-1261
Author(s):  
Mourad Akdad ◽  
Mohamed Eddouks

Aims: The present study was performed in order to analyze the antihypertensive activity of Micromeria graeca (L.) Benth. ex Rchb. Background: Micromeria graeca (L.) Benth. ex Rchb is an aromatic and medicinal plant belonging to the Lamiaceae family. This herb is used to treat various pathologies such as cardiovascular disorders. Meanwhile, its pharmacological effects on the cardiovascular system have not been studied. Objective: The present study aimed to evaluate the effect of aqueous extract of aerial parts of Micromeria graeca (AEMG) on the cardiovascular system in normotensive and hypertensive rats. Methods: In this study, the cardiovascular effect of AEMG was evaluated using in vivo and in vitro investigations. In order to assess the acute effect of AEMG on the cardiovascular system, anesthetized L-NAME-hypertensive and normotensive rats received AEMG (100 mg/kg) orally and arterial blood pressure parameters were monitored during six hours. In the sub-chronic study, rats were orally treated for one week, followed by blood pressure assessment during one week of treatment. Blood pressure was measured using a tail-cuff and a computer-assisted monitoring device. In the second experiment, isolated rat aortic ring pre-contracted with Epinephrine (EP) or KCl was used to assess the vasorelaxant effect of AEMG. Results: Oral administration of AEMG (100 mg/kg) provoked a decrease of arterial blood pressure parameters in hypertensive rats. In addition, AEMG induced a vasorelaxant effect in thoracic aortic rings pre-contracted with EP (10 μM) or KCl (80 mM). This effect was attenuated in the presence of propranolol and methylene blue. While in the presence of glibenclamide, L-NAME, nifedipine or Indomethacin, the vasorelaxant effect was not affected. Conclusion: This study showed that Micromeria graeca possesses a potent antihypertensive effect and relaxes the vascular smooth muscle through β-adrenergic and cGMP pathways.


Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 776
Author(s):  
Shipra Kumari ◽  
Bashistha Kumar Kanth ◽  
Ju young Ahn ◽  
Jong Hwa Kim ◽  
Geung-Joo Lee

Genome-wide transcriptome analysis using RNA-Seq of Lilium longiflorum revealed valuable genes responding to biotic stresses. WRKY transcription factors are regulatory proteins playing essential roles in defense processes under environmental stresses, causing considerable losses in flower quality and production. Thirty-eight WRKY genes were identified from the transcriptomic profile from lily genotypes, exhibiting leaf blight caused by Botrytis elliptica. Lily WRKYs have a highly conserved motif, WRKYGQK, with a common variant, WRKYGKK. Phylogeny of LlWRKYs with homologous genes from other representative plant species classified them into three groups- I, II, and III consisting of seven, 22, and nine genes, respectively. Base on functional annotation, 22 LlWRKY genes were associated with biotic stress, nine with abiotic stress, and seven with others. Sixteen unique LlWRKY were studied to investigate responses to stress conditions using gene expression under biotic and abiotic stress treatments. Five genes—LlWRKY3, LlWRKY4, LlWRKY5, LlWRKY10, and LlWRKY12—were substantially upregulated, proving to be biotic stress-responsive genes in vivo and in vitro conditions. Moreover, the expression patterns of LlWRKY genes varied in response to drought, heat, cold, and different developmental stages or tissues. Overall, our study provides structural and molecular insights into LlWRKY genes for use in the genetic engineering in Lilium against Botrytis disease.


Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 745
Author(s):  
Enrico Bergamaschi ◽  
Giacomo Garzaro ◽  
Georgia Wilson Jones ◽  
Martina Buglisi ◽  
Michele Caniglia ◽  
...  

Carbon nanotubes (CNTs) and carbon nanofibers (CNFs) are erroneously considered as singular material entities. Instead, they should be regarded as a heterogeneous class of materials bearing different properties eliciting peculiar biological outcomes both in vitro and in vivo. Given the pace at which the industrial production of CNTs/CNFs is increasing, it is becoming of utmost importance to acquire comprehensive knowledge regarding their biological activity and their hazardous effects in humans. Animal studies carried out by inhalation showed that some CNTs/CNFs species can cause deleterious effects such as inflammation and lung tissue remodeling. Their physico-chemical properties, biological behavior and biopersistence make them similar to asbestos fibers. Human studies suggest some mild effects in workers handling CNT/CNF. However, owing to their cross-sectional design, researchers have been as yet unable to firmly demonstrate a causal relationship between such an exposure and the observed effects. Estimation of acceptable exposure levels should warrant a proper risk management. The aim of this review is to challenge the conception of CNTs/CNFs as a single, unified material entity and prompt the establishment of standardized hazard and exposure assessment methodologies able to properly feeding risk assessment and management frameworks.


2021 ◽  
Vol 10 (12) ◽  
pp. 2721
Author(s):  
Nobuto Nakanishi ◽  
Shigeaki Inoue ◽  
Rie Tsutsumi ◽  
Yusuke Akimoto ◽  
Yuko Ono ◽  
...  

Ultrasound has become widely used as a means to measure the rectus femoris muscle in the acute and chronic phases of critical illness. Despite its noninvasiveness and accessibility, its accuracy highly depends on the skills of the technician. However, few ultrasound phantoms for the confirmation of its accuracy or to improve technical skills exist. In this study, the authors created a novel phantom model and used it for investigating the accuracy of measurements and for training. Study 1 investigated how various conditions affect ultrasound measurements such as thickness, cross-sectional area, and echogenicity. Study 2 investigated if the phantom can be used for the training of various health care providers in vitro and in vivo. Study 1 showed that thickness, cross-sectional area, and echogenicity were affected by probe compression strength, probe angle, phantom compression, and varying equipment. Study 2 in vitro showed that using the phantom for training improved the accuracy of the measurements taken within the phantom, and Study 2 in vivo showed the phantom training had a short-term effect on improving the measurement accuracy in a human volunteer. The new ultrasound phantom model revealed that various conditions affected ultrasound measurements, and phantom training improved the measurement accuracy.


Zygote ◽  
2020 ◽  
Vol 28 (2) ◽  
pp. 154-159
Author(s):  
Juliana I. Candelaria ◽  
Anna C. Denicol

SummaryPreantral follicles are a potential reservoir of oocytes to be used in assisted reproductive technologies. With the increasing interest in developing techniques to grow preantral follicles in vitro, and as the bovine emerges as an appropriate model species to understand human folliculogenesis, the establishment of an accurate classification of developmental stages is needed. Classification of bovine preantral follicles has been mostly based on histological analysis and estimation models, which may not translate well to correctly characterize preantral follicles isolated from the ovary. In this study, we classified bovine preantral follicles by morphology upon isolation, determined diameter and number of granulosa cells by direct counting, and compared our results with previous studies reporting bovine preantral follicle classification. Follicles were isolated via homogenization of ovary tissue and classified into primary, early secondary and secondary stage based on morphology and number of layers of granulosa cells. Diameter was individually measured and Hoechst 33342 was used as a nuclear stain to count granulosa cells. We found that follicles classified by morphology into primary, early secondary, and secondary had different mean diameter and cell number (P < 0.01); cell number and diameter were positively correlated, as were cell density and cell number in each developmental stage (P < 0.01). Results obtained here were mostly in agreement with previous classifications based on histological sections and on isolated follicles, with some discrepancies. The present data add accuracy to classification of bovine preantral follicles that is critical to optimize culture conditions to produce developmentally competent oocytes.


Development ◽  
1988 ◽  
Vol 102 (4) ◽  
pp. 793-803 ◽  
Author(s):  
V.E. Papaioannou ◽  
K.M. Ebert

Total cell number as well as differential cell numbers representing the inner cell mass (ICM) and trophectoderm were determined by a differential staining technique for preimplantation pig embryos recovered between 5 and 8 days after the onset of oestrus. Total cell number increased rapidly over this time span and significant effects were found between embryos of the same chronological age from different females. Inner cells could be detected in some but not all embryos of 12–16 cells. The proportion of inner cells was low in morulae but increased during differentiation of ICM and trophectoderm in early blastocysts. The proportion of ICM cells then decreased as blastocysts expanded and hatched. Some embryos were cultured in vitro and others were transferred to the oviducts of immature mice as a surrogate in vivo environment and assessed for morphology and cell number after several days. Although total cell number did not reach in vivo levels, morphological development and cell number increase was sustained better in the immature mice than in vitro. The proportion of ICM cells in blastocysts formed in vitro was in the normal range.


Development ◽  
1977 ◽  
Vol 41 (1) ◽  
pp. 79-92
Author(s):  
Rosita Smith ◽  
Anne McLaren

In normal mouse embryos developing in vivo, the first appearance of the blastocyst cavity was found to be associated more closely with developmental age, judged by cell number, than with chronological age, i.e. elapsed time since ovulation. When development was slowed by in vitro culture, formation of the blastocoele was delayed. However, cell number itself was not a critical factor, since the number of cells per embryo could be doubled or tripled or halved by experimental manipulation without substantially affecting the timing of blastocoele formation. Experiments in which one cell division was suppressed with cytochalasin-B, leading to tetraploidy, showed that the number of cell divisions since fertilization was also not critical. A possible role is suggested either for nucleocytoplasmic ratio, or for the number of nuclear or chromosomal divisions or DNA replications since fertilization, all of which increase during cleavage.


Development ◽  
1981 ◽  
Vol 61 (1) ◽  
pp. 277-287
Author(s):  
A. J. Copp

The number of trophoblast giant cells in outgrowths of mouse blastocysts was determined before, during and after egg-cylinder formation in vitro. Giant-cell numbers rose initially but reached a plateau 12 h before the egg cylinder appeared. A secondary increase began 24 h after egg-cylinder formation. Blastocysts whose mural trophectoderm cells were removed before or shortly after attachment in vitro formed egg cylinders at the same time as intact blastocysts but their trophoblast outgrowths contained fewer giant cells at this time. The results support the idea that egg-cylinder formation in vitro is accompanied by a redirection of the polar to mural trophectoderm cell movement which characterizes blastocysts before implantation. The resumption of giant-cell number increase in trophoblast outgrowths after egg-cylinder formation may correspond to secondary giant-cell formation in vivo. It is suggested that a time-dependent change in the strength of trophoblast cell adhesion to the substratum occurs after blastocyst attachment in vitro which restricts the further entry of polar cells into the outgrowth and therefore results in egg-cylinder formation.


Development ◽  
1975 ◽  
Vol 33 (1) ◽  
pp. 205-216
Author(s):  
Anne McLaren

1. Of 30 mice born from aggregation of embryos from a multiple recessive strain with F1 embryos carrying the contrasting alleles, 4 females and 20 males proved to be overtly chimaeric. 2. Three XX/XX females, five XY/XY males and eight XY/XX males were identified by chromosome analysis. Thus 50 % of the population analysed were sex chimaeras, and all of these developed as phenotypic males, though one showed evidence of hermaphroditism. 3. In seven XY/XX chimaeras that bred, the genetic component undergoing spermatogenesis coincided in every case with the component identified by chromosome morphology as XY. 4. The F1 component predominated in metaphase plates derived from cultured blood cells. Comparison with direct preparations from bone marrow suggested selection in favour of F1 cells, either through differential proliferation of stem cells in vivo or differential response to phytohaemagglutinin in vitro. 5. In XY/XX males, the percentage of XX cells detected varied from 1 % to 98 % in blood, and from 0 % to 80 % in bone marrow. 6. Of eight ‘single-sex’ chimaeras progeny-tested (three XX/XX, five XY/XY), only one showed evidence of a mixed population of germ cells. The proportion of the two types of progeny varied significantly from litter to litter, but was unrelated to the age of the male.


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