The salivary glands often are severely and permanently damaged by therapeutic irradiation for cancer of the head and neck. The markedly reduced quantity and quality of saliva results in greatly increased susceptibility to dental caries and infection of the oral mucosa and alveolar bone. Recently, subcapsular injection of cultured mouse salivary gland cells has achieved a significant degree of regeneration in a previously irradiated mouse salivary gland. However, the recovery was limited to one lobule. Here we describe a method of delivering donor rat salivary gland cells via the main duct that distributes several thousand cells throughout the recipient rat's salivary gland. The donated cells exhibited the cytodifferentiation of the structures in which they lodged, i.e., acini, granular convoluted tubules and the several types of duct. This method may facilitate the simultaneous functional recovery of almost all of the lobules of irradiated rat salivary glands. Keywords differentiation; radiation; rat; regeneration; salivary glands; stem cells Salivary glands in the path of therapeutic irradiation for head and neck cancer often are severely damaged despite recent modifications in radiation delivery, especially when the patient is unable to tolerate drugs that offer partial protection of normal tissues (reviewed by Redman 2008). This results in chronic oral mucositis and increased susceptibility to periodontitis and dental caries. Without meticulous home and professional dental care, rampant caries ensues, and the sequellae of periapical infections and extractions carry a high risk of precipitating osteonecrosis. It was suggested (Coppes et al. 2001, Nagler 2002, Redman 2008 that the reason for the poor functional recovery of salivary glands subjected to greater than 35 Gray of ionizing radiation is that the mature acinar and ductal cells and their progenitors are either destroyed or rendered incapable of proliferation. It follows that the most promising approach to restoring function in the damaged glands would be to promote regeneration via injection of donor salivary gland cells or the patient's marrow stem cells. The stem cells have a propensity to migrate into badly damaged tissues and differentiate into functioning replacement cells. Thus, simply increasing the number of the otherwise uncommon stem cells in the circulation might boost the number migrating into irradiated salivary glands. This has been tried in mouse (Lombaert et al. 2006). Some of the stem cells mobilized by granulocyte-stimulating factor indeed did lodge in the irradiated glands and seemed to partially ameliorate the damage, but When cells dissocciated from such a cultue were injected into an irradiated female mouse salivary gland, they proliferated and differentiated to such an extent that an entire lobule underwent significant structural and functional restoration. In situ hybridization for the Y-chromosome revealed that most of the cells participating in the restoration were male, i.e,, donor cells. This is a landmark achievemen...
On the left side the shadow showed dilatation of the pelvis and calices, and dilatation of the ureter along its entire length.On October 29th, 1930, a specimen of the fluid passed per rectum was examined. It was brownish in colour with a slight admixture of faeces. The specific gravity was 1010, the reaction alkaline, and there was a trace of albumen. On centrifugalising, no pus cells could be detected.To complete the examination of this boy, he was sigmoidoscoped after the injection of indigocarmine deeply into the buttock. The mucous membrane of the bowel looked normal in every respect. The instrument could not be passed far enough to see the orifices of the ureters. Urine, comparatively free from admixture with faxes, flowed into the instrument, and was collected for examination. A tube was placed in the rectum and the blue colour of indigocarmine was not apparent in the fluid collected till after the lapse of one and a half hours. This fluid contained 1 per cent. of urea.Intravenous pyelography in this patient clearly shows that the structure and function of the right kidney are seriously damaged, and that a destructive process is also taking place on the left side. The blood urea, which was 27 mgm. per 100 C.C. before the second operation, isnow 51. The absence of pus is against infection of the kidneys. It is obvious, however, that there is back pressure on both sides. The unfortunate occurrence of temporary blocking after both operations may be in part to blame, but I am inclined to think that some degree of hydronephrosis is likely to occur after this operation of transplantation of the ureters. I n future operations an attempt might perhaps be made to obviate this by embedding the terminal portions of the ureters more loosely in the wall of the pelvic colon.Owing to the rise in blood urea and the results of intravenous pyelography, it was considered advisable to postpone indefinitely operation on the bladder and penis-especially as the patient himself and his parents are well satisfied with his present condition.
AI.TIIOI:GII the endoscopic: mcthod of treatment of sirnplc papill<:mata of thc t)laddcr t)y high-freqiieiic!y currcnts was introduced by Beer, of' Sew York, so long ago as 1910, and maiiy sri1)scqiicnt writers on thc subjcct, including 'Yhomson-\+'alkcr i n this country, have writtcn excellmt dcsoriptioiis thereof', its advantages do riot appear t o have hecri appreciated sufficiently to lead t o its universal adoption. The reasons for belicving that trans-urethral diathcririic cauterization should replacc the oldcr procedure of' suprapubic
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.