PubMed · 5078614
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P D Jackson. 1972. Parotid calculus.. https://pubmed.ncbi.nlm.nih.gov/5078614/
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BACKGROUND: In breast-cancer research, we lack reproducible non-invasive access to breast tissue. Breast cancer is thought to start in the lining of the milk duct or lobule. We have had no direct access to this area other than in tissue removed surgically or by fine-needle aspiration. Our objective was to explore an intraductal approach to studying breast cancer and precancerous changes by duct cannulation and endoscopy. METHODS: In this pilot study, women in a university hospital were asked to participate. Nine patients with previously diagnosed ductal carcinoma-in-situ (DCIS) or invasive breast cancer who were about to undergo mastectomy under general anaesthesia agreed. After the patient was asleep but before the operation, we spent 15 minutes cannulating their ducts, obtaining washings, and attempting endoscopy. The ducts that had been cannulated were marked by instillation of dye or other materials, the nipple was sutured shut, and the mastectomy proceeded as planned. The mastectomy specimen underwent extensive histopathological examination. FINDINGS: We were successful in intraductal cannulation and endoscopy in seven of the nine patients. In five of the nine, we obtained epithelial cells in the washings. In one the cells were consistent with proliferative disease, in three there was atypical epithelium, and in one there was frank DCIS. With several different contrast materials injected into separate duct orifices, DCIS was confined to a single duct system. INTERPRETATION: We found that the intraductal approach is feasible for the study of the early changes of breast cancer Technical difficulties include identification of the breast duct orifices, determining the distensibility of the duct, and developing a reliable technique to obtain washings.
Sympathetic neurones supplying the submandibular salivary gland innervate blood vessels, secretory and myoepithelial cells. Here we examined whether these functionally different sympathetic neurones show distinct reflex response patterns. In anaesthetized rats, single unit activity was recorded from postganglionic axons projecting to the gland. Neurones were tested for their responses to stimulation of baroreceptors, cutaneous nociceptors and cold receptors and to gustatory stimuli applied to the tongue. Respiratory modulation was also analysed. Only a few postganglionic neurones identified electrically (5-10%) were spontaneously active. They were excited by noxious and cold stimuli, inhibited by baroreceptor stimulation and exhibited respiratory modulation. None of the units responded to gustatory stimuli. Thus, in anaesthetized rats spontaneously active sympathetic neurones supplying the submandibular gland behave like vasoconstrictor neurones. Sympathetic neurones with other functions are probably silent.
Cortical motor maps of first dorsal interosseus (FDI), abductor digit minimi (ADM) and wrist flexors muscles were produced following transcranial focal magnetic stimulation of the contralateral motor areas in seven volunteers. Motor evoked potentials (MEPs) were recorded before and during median and radial nerves anaesthetic block at wrist. Results indicated that the FDI muscle cortical representation was significantly reduced; this muscle was entirely "enveloped' in the hand region deprived of its cutaneous sensory information, despite maintaining its usual proprioceptive feed-back and strength via the ulnar nerve. On the contrary, the ADM (serving as "control condition' because outside the anaesthetised hand area) cortical representation was unchanged, even if showing a tendency to enlarge in the topographic maps. No amplitude changes of compound muscle action potentials of ADM and FDI during peripheral stimulations were observed, while changes in F-wave responses were detected in both muscles. No significant topographic changes were found for the wrist flexors muscles. A possible explanation for these "short term' rearrangements of brain motor maps is given on the basis of neural plasticity mechanisms due to the loss of tonic cutaneous inputs on cortical and spinal motoneurons.