scholarly journals Onset of the acquired potentiality for fusion in the palatal shelves of rats

Development ◽  
1966 ◽  
Vol 16 (1) ◽  
pp. 171-182
Author(s):  
M. Pourtois

This paper is concerned with that phase of palate development in rats leading to fusion of the shelves in the midline. Previous experimentation in palate development in mammals has encompassed both the earlier phase of assumption of the horizontal position of the palatal shelves, and the subsequent approximation and fusion of the shelves. Since the two processes do not occur simultaneously and can theoretically be studied separately, it was possible and feasible to confine the experiment to the later fusion phase. The present research was designed to eliminate the possible confounding effects of palate rotation in vitro on the fusion of the shelves by approximation of the explanted palatal shelves in the same horizontal plane, irrespective of their original positions in the oral cavity. Current theories of cleft palate pathogenesis hold that either the palatal shelves fail to assume (rotate to) the horizontal position, or, that having done so, they fail to fuse.

Development ◽  
1980 ◽  
Vol 57 (1) ◽  
pp. 119-128
Author(s):  
Ravindra M. Shah ◽  
David T. W. Wong

Morphogenesis of palate was studied in normal and 5-fluorouracil-treated hamster fetuses. The results showed that normal palatal development was completed between days 12 and 13 of gestation. In 5-fluorouracil-assaulted palate the reorientation of shelves from a vertical to horizontal plane was delayed. Crown-rump length, gestational age and fetal weight were reliable predictors of the stages of normal palatal development, whereas the morphological rating system was not. Following 5-fiuorouracil treatment, however, crown-rump length, weight and morphological rating were poor indicators of the stage of palatal development.


Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 172
Author(s):  
Mariusz Dziadas ◽  
Adam Junka ◽  
Henryk Jeleń

Eugenyl-β-D-glucopyranoside, also referred to as Citrusin C, is a natural glucoside found among others in cloves, basil and cinnamon plants. Eugenol in a form of free aglycone is used in perfumeries, flavourings, essential oils and in medicinal products. Synthetic Citrusin C was incubated with human saliva in several in vitro models together with substrate-specific enzyme and antibiotics (clindamycin, ciprofloxacin, amoxicillin trihydrate and potassium clavulanate). Citrusin C was detected using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Citrusin C was completely degraded only when incubated with substrate-specific A. niger glucosidase E.C 3.2.1.21 (control sample) and when incubated with human saliva (tested sample). The addition of antibiotics to the above-described experimental setting, stopped Citrusin C degradation, indicating microbiologic origin of hydrolysis observed. Our results demonstrate that Citrusin C is subjected to complete degradation by salivary/oral cavity microorganisms. Extrapolation of our results allows to state that in the human oral cavity, virtually all β-D-glucosides would follow this type of hydrolysis. Additionally, a new method was developed for an in vivo rapid test of glucosidase activity in the human mouth on the tongue using fluorescein-di-β-D-glucoside as substrate. The results presented in this study serve as a proof of concept for the hypothesis that microbial hydrolysis path of β-D-glucosides begins immediately in the human mouth and releases the aglycone directly into the gastrointestinal tract.


Author(s):  
Chengyi Fu ◽  
Shu Lou ◽  
Guirong Zhu ◽  
Liwen Fan ◽  
Xin Yu ◽  
...  

Objective: To identify new microRNA (miRNA)-mRNA networks in non-syndromic cleft lip with or without cleft palate (NSCL/P).Materials and Methods: Overlapping differentially expressed miRNAs (DEMs) were selected from cleft palate patients (GSE47939) and murine embryonic orofacial tissues (GSE20880). Next, the target genes of DEMs were predicted by Targetscan, miRDB, and FUNRICH, and further filtered through differentially expressed genes (DEGs) from NSCL/P patients and controls (GSE42589), MGI, MalaCards, and DECIPHER databases. The results were then confirmed by in vitro experiments. NSCL/P lip tissues were obtained to explore the expression of miRNAs and their target genes.Results: Let-7c-5p and miR-193a-3p were identified as DEMs, and their overexpression inhibited cell proliferation and promoted cell apoptosis. PIGA and TGFB2 were confirmed as targets of let-7c-5p and miR-193a-3p, respectively, and were involved in craniofacial development in mice. Negative correlation between miRNA and mRNA expression was detected in the NSCL/P lip tissues. They were also associated with the occurrence of NSCL/P based on the MGI, MalaCards, and DECIPHER databases.Conclusions: Let-7c-5p-PIGA and miR-193a-3p-TGFB2 networks may be involved in the development of NSCL/P.


2021 ◽  
Author(s):  
Lin Tao ◽  
M. Paul Chiarelli ◽  
Sylvia I. Pavlova ◽  
Joel L. Schwartz ◽  
James V. DeFrancesco ◽  
...  

Abstract Certain soil microbes resist and metabolize polycyclic aromatic hydrocarbons (PAHs). The same is true for certain skin microbes. Oral microbes have the potential to oxidize tobacco PAHs to increase their ability to cause cancer. We hypothesized that oral microbes that resist high levels of PAH in smokers exist and can be identified based on their resistance to PAHs. We isolated bacteria and fungi that survived long term in minimal media with PAHs as the sole carbon source from the oral cavity in 11 of 14 smokers and only 1 of 6 nonsmokers. Of bacteria genera that included species that survived harsh PAH exposure in vitro, all were found at trace levels on the oral mucosa, except for Staphylococcus and Actinomyces. Two PAH-resistant strains of Candida albicans (C. albicans) were isolated from smokers. C. albicans is found orally at high levels in tobacco users and some Candida species can metabolize PAHs. The two C. albicans strains were tested for metabolism of two model PAH substrates, pyrene and phenanthrene. The result showed that the PAH-resistant C. albicans strains did not metabolize the two PAHs. In conclusion, evidence for large scale oral microbial metabolism of tobacco PAHs by common oral microbes remains lacking.


2014 ◽  
Vol 3 (21) ◽  
pp. 5748-5752 ◽  
Author(s):  
Pratap Rao S ◽  
Jyothsna B ◽  
Sana Salim Khan ◽  
Sravanthi M ◽  
Prasad C N
Keyword(s):  

2001 ◽  
Vol 15 (6) ◽  
pp. 665-672 ◽  
Author(s):  
Naoko Shimizu ◽  
Hiroaki Aoyama ◽  
Noriyuki Hatakenaka ◽  
Masahiro Kaneda ◽  
Shoji Teramoto

2003 ◽  
pp. 267-274
Author(s):  
M. Michele Pisano ◽  
Robert M. Greene

2021 ◽  
Vol 8 ◽  
pp. 37-46
Author(s):  
Katarzyna Niemirowicz-Laskowska ◽  
Joanna Mystkowska ◽  
Dawid Łysik ◽  
Sylwia Chmielewska ◽  
Łukasz Suprewicz ◽  
...  

Saliva plays a crucial role in maintaining homeostasis not only within the oral cavity but also in further sections of the gastrointestinal tract. Pleiotropic properties of saliva include participation in the digestion of carbohydrates, cleansing and moisturizing the oral cavity, and maintaining the composition of the oral microbiome. The result of impaired function of the salivary gland is reduced salivation – hyposalivation, leading to dry mouth – xerostomia. It is established that numerous physiological factors (age, sex, weight change) and pathological factors (polytherapy, head and neck cancer, coexisting diseases such as diabetes, depression, cardiovascular diseases) lead to the reduction in saliva secretion, and in effect, causing a dry mouth. Treatment of salivary secretion disorders involves pharmacological therapy (including hormone therapy) or replacement therapy which based on the use of saliva substitutes. In the case of disturbances in the secretion of natural saliva, the application of the artificial saliva preparations should support the chewing processes, moisturize the oral cavity, and fulfill the biological functions of saliva. However, to date, on the pharmaceutical market, there are no saliva substitutes that meet the biological criteria and maintaining favorable physicochemical properties and rheological parameters. Taking into account the problems of the patients which are burden by impaired salivary secretion, the aim of our research was to attempt to develop an artificial saliva preparation that reflecting as much as possible the properties of natural saliva, both in terms of mechanical and biological properties. As part of the research, the chemical composition was developed and a detailed study of the physicochemical and rheological parameters of artificial saliva preparations containing mucins as well as their microbiological and biocompatibility assessment, at in vitro level were carried out.


Development ◽  
1975 ◽  
Vol 34 (2) ◽  
pp. 485-495
Author(s):  
L. Brinkley ◽  
G. Basehoar ◽  
A. Branch ◽  
J. Avery

An in vitro system was devised which supports palate development in partially dissected embryonic mouse heads. The heads were suspended in the culture chamber so that they were not held in a fixed orientation and were constantly surrounded with a fluid medium. Under these circumstances the developing palate must effect closure without the aid of gravitational forces. The culture medium was constantly circulated, gassed with 95% O2, 5% CO2 using hollow fiber gas permeation devices, and kept at 34°C. Swiss-Webster mouse embryos of 12 days 12–18 h (ca. 48 h prior to expected in vivo closure) or 13 days 8–14 h (ca. 24 h prior to closure) were used to test the ability of the system to support palatal development. Embryonic heads were dissected in one of two ways before culture: brain and tongue removed, or brain, tongue and mandible removed. After 24 h in culture, preparations of either age with only the brain and tongue removed had made substantially greater progress than their counterparts with the brain, tongue and mandible removed. With only the brain and tongue removed, the palatal shelves were contacting, adhered or fused in 67 % of the older embryos, whereas most of the embryos of the same age cultured with the brain, tongue and mandible removed had shelves that were not fully elevated and still separated by a moderate gap. Thus for maximal progress in the present system, the oral cavity must be intact except for the tongue.


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