A lack of avoidance of flank gland secretions by male Syrian hamsters

It is commonly assumed that sexually dimorphic cutaneous glands are important in supporting inter-male aggression in rodents. Such an intimidation role has been hypothesized as the function of the hamsters' flank gland. Two experiments failed to find avoidance of male flank odors. In one, subordinate males entered and spent comparable amounts of time in clean areas and areas scented with the dominant's flank secretion. In the other study, males were found to respond differentially to flank odors obtained from the subject, a familiar and a novel male. Although the males seemed to have habituated to the odor of the familiar male, there was no suggestion of avoidance of any of these odors. It may be that the males' flank odor is relevant not to other males but to females.     

A role for electron microscopy in salivary gland neoplasms

Undoubtedly, electron microscopy has a specific role to play in the diagnosis of a select group of salivary gland neoplasms. However, this tool has a current central role, along with immunohistochemical techniques, in elucidating morphogenetic processes in salivary gland tumors. New information gained from ultrastructural surveys of these tumors can be applied to improving classification and the diagnostic problems that are not infrequent for the surgical pathologist with salivary gland lesions.     

A possible role for cyclic guanosine monophosphate in the rat pineal gland

Adrenergic stimulation of pinealocytes induces an increase of both cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). However, for cGMP no biological effects have been demonstrated so far. Therefore we tested the effects of the analog 8-bromo-cGMP on synaptic ribbon numbers and on melatonin synthesis as reflected by N-acetyltransferase (NAT) activity in the rat pineal gland in vitro. Incubation for 6 h with 8-bromo-cGMP did not change the activity of serotonin NAT but it increased the number of synaptic ribbons. These results indicate that cGMP is involved as a second messenger in the regulation of synaptic ribbon numbers in the rat pineal gland.     

A physiological role for protoporphyrin IX photodynamic action in the rat Harderian gland?

Aims: The lipid‐secreting exocrine Harderian gland contains a large amount of porphyrins (mainly protoporphyrin IX, PPIX) in the glandular cells, the physiological significance of which is rather poorly understood. Methods: In the present study, the possibility of using Fura‐2 to measure intracellular calcium ([Ca²⁺]_c) changes in these cells was assessed. Results: It was found that when Fura‐2‐loaded cells were excited by light at 340/380 nm, [Ca²⁺]_c increased spontaneously, indicating a photodynamic action powered by light at 340/380 nm. In contrast, with the visible spectrum calcium probe Fluo‐3 (λ_ex = 475 nm), carbachol at 10 μm induced [Ca²⁺]_c increase; [Ca²⁺]_c did not change without carbachol stimulation. Brief illumination with light at 340/380 nm induced a large [Ca²⁺]_c increase in Fluo‐3‐loaded cells. Photodynamic stimulation of [Ca²⁺]_c increase was confirmed with an exogenous photosensitizer sulphonated aluminium phthalocyanine (SALPC) and visible light (>580 nm). The wavelength‐dependence of the [Ca²⁺]_c increase correlates well with the excitation spectrum of the isolated Harderian glandular cells. Conclusion: These data suggest that PPIX present in rat Harderian glandular cells plays the role of a photosensitizer which upon activation by UVA and blue components of daylight and subsequent singlet oxygen generation, triggers [Ca²⁺]_c increase and secretory response. The PPIX photodynamic action may also play a potential role in photic entrainment of the central circadian clock.     

Heparan sulfate fine-tunes stromal-epithelial communication in the prostate gland

Several studies reported the concerted and mutual communication between the prostate epithelium and stroma, which determines the final organ architecture and function, but gets awry in cancer. Deciphering the mechanisms involved in this communication is crucial to find new therapeutic strategies. HS sequesters a number of secreted growth factors and cytokines, controlling their bioavailability to the target cells, suggesting that HS is an important regulator of the extracellular matrix (ECM) and a key player in the cell-cell and cell-microenvironment communication during prostate morphogenesis and physiology. We propose that by controlling HS biosynthesis and sulfation pattern, as well as the cleavage of the HS chain and/or the shedding of proteoglycans, epithelial and stromal cells are able to precisely tune the availability of signaling molecules and modulate ligand-receptor interaction and intracellular signal transduction.     

Lymphaticovenous communication in the mammary gland of the female dog

Lymphaticovenous Communications were searched in the mammary glands of 24 bitches. Injections of indian ink into the interstice of living animals were followed after death by the filling of the veins with latex and barium sulphate. Afterwards, the used techniques were: microdissection, angiography, clarification and histological section. The results obtained would seem to prove the existence of Lymphovenous Anastomoses. The roles of these communications in the canine mammary gland neoplasia are discussed.     

Regional analysis of neurofilament protein immunoreactivity in the hamster's cortex

The laminar distribution of several distinct populations of neurofilament protein containing neurons has been used as a criterion for the delineation of cortical areas in hamsters. SMI-32 is a monoclonal antibody that recognizes a non-phosphorylated epitope on the medium- and high-molecular weight subunits of neurofilament proteins. As in carnivores and primates, SMI-32 immunoreactivity in the hamster neocortex was present in cell bodies, proximal dendrites and axons of some medium and large pyramidal neurons located in cortical layers III, V and VI. A small population of labeled multipolar cells was also found in layer IV. Neurofilament protein immunoreactive neurons were found throughout isocortical areas. Very few labeled cells were encountered in supplemental motor area, insular cortex, medial portion of associative visual cortex and in parietal association cortex. Our data indicate that SMI-32 immunoreactive cells can be efficiently used to trace boundaries between neocortical areas in the hamster's brain. The regional distribution SMI-32 immunoreactivity in the hamster cortex corresponds quite closely with cortical areas as defined by their cytoarchitecture and myeloarchitecture. The primary sensory cortical areas contain the most intense of SMI-32 immunoreactivity and are also those with the highest density of myelinated axons. Very low SMI-32 immunoreactivity was found in orbital, insular, perirhinal, cingulate and infralimbic cortices, which are also poor in myelinated axons. This supports the association between SMI-32 immunoreactivity and myelin contents.     

A conceptual model of the role of communication in surrogate decision making for hospitalized adults

Objective

To build a conceptual model of the role of communication in decision making, based on literature from medicine, communication studies and medical ethics.

Methods

We proposed a model and described each construct in detail. We review what is known about interpersonal and patient–physician communication, described literature about surrogate–clinician communication, and discussed implications for our developing model.

Results

The communication literature proposes two major elements of interpersonal communication: information processing and relationship building. These elements are composed of constructs such as information disclosure and emotional support that are likely to be relevant to decision making. We propose these elements of communication impact decision making, which in turn affects outcomes for both patients and surrogates. Decision making quality may also mediate the relationship between communication and outcomes.

Conclusion

Although many elements of the model have been studied in relation to patient–clinician communication, there is limited data about surrogate decision making. There is evidence of high surrogate distress associated with decision making that may be alleviated by communication-focused interventions. More research is needed to test the relationships proposed in the model.

Practice implications

Good communication with surrogates may improve both the quality of medical decisions and outcomes for the patient and surrogate.     

Development of the flank organ (scent gland) of the Syrian hamster II. Postnatal development

In the first paper of this series, the prenatal development of the flank organ (scent gland) of the Syrian hamster was described. The present paper is concerned with the postnatal development of this organ. The embryology of the organ actually continues into postnatal life, until, during the fifth day, the organ attains the degree of development characteristic of general body skin at birth. Subsequently, an accelerated growth rate results in a conspicuous and characteristic hypertrophy of the gland relative to surrounding integument. During the acquisition of this hypertrophy two opposite developmental gradients are involved, i.e., a series of consecutive centripetal waves of hair cycling and a centrifugal gradient of sebaceous gland development. Maturation of the gland, including changes in its pigmentation and the onset of sexual dimorphism, is discussed in relation to pertinent literature.     

Potential role for inhibition of protein phosphatase 2A tumor suppressor in salivary gland malignancies

The aetiology and pathogenesis of salivary gland malignancies remain unknown. To reveal novel molecular factors behind the development of salivary gland cancer, we performed gene expression analyses from Smgb‐Tag mouse salivary gland samples. The overall purpose was to apply these results for clinical use to find new approaches for both possible therapeutic targets and more accurate diagnostic tools. Smgb‐Tag mouse strain, in which salivary neoplasms arise through a dysplastic phase in submandibular glands, was investigated using genome‐wide microarray expression analysis, ingenuity pathway analysis, RT‐PCR, and immunohistochemistry. Thirty‐eight human salivary gland adenoid cystic carcinoma samples were investigated using immunohistochemistry for validation purposes. Our genome‐wide study showed that Ppp2r1b, a PP2A subunit encoding tumor suppressor gene, is underexpressed in submandibular gland tumors of Smgb‐Tag mice. mTOR signaling pathway was significantly enriched and mTOR linked PP2A subunit gene B55 gamma was significantly underexpressed in the analyses. Furthermore, parallel immunohistochemical analysis of three PP2A inhibitors demonstrated that two PP2A inhibitors, CIP2A and SET, are highly expressed in both dysplastic and adenocarcinomatous tumors of the Smgb‐Tag mice. In addition, all 38 investigated human salivary adenoid cystic carcinoma samples stained positively for CIP2A and most for SET. Finally, p‐S6 staining showed activation of mTOR pathway in human adenoid cystic carcinoma samples. Our results suggest that PP2A inhibition either via PP2A subunit underexpression or PP2A inhibitor overexpression play an important role in the formation of salivary gland malignancy, potentially due to mTOR signaling activation. © 2015 Wiley Periodicals, Inc.     

Defining the role of myoepithelium in salivary gland neoplasia

Neoplastic myoepithelium is considered to be the key cellular participant in morphogenetic processes responsible for the variable histologic appearances of many salivary gland tumors. Nevertheless, controversy still exists concerning its participation in some types of salivary gland neoplasms. This has been largely due to the difficulty in fully characterizing the wide spectrum of morphologic and immunophenotypic expressions of neoplastic myoepithelium compared with the normal counterpart. However, in recent years, our understanding regarding the phenotypic, immunophenotypic, ultrastructural, and biochemical properties of myoepithelium has advanced. Here we discuss the role of neoplastic myoepithelium in the scope of salivary gland neoplasia and present this information from a practical diagnostic standpoint.     

The role of the pineal gland in magnetobiological effects

The problem of pineal mognetosensitivity is considered in light of modem magnetobiology publications and the authors' own findings. It has been shown that electromagnetic exposure of different parameters affects pineal activity. Changes in the temporal organization of biological systems are suggested to be the main effect of electromagnetic exposure. Modern data evidence that there are magnetoreceptive structures aside from the pineal gland.     

A transient projection from the trigeminal brainstem complex to the superficial layers of the hamster's superior colliculus

Summary Anterograde tracing with the carbocyanine dye, Di-I, was used to describe the normal postnatal development of the projection from the trigeminal (V) brainstem complex to the superior colliculus (SC) in hamster. In adult hamsters, this projection is completely restricted to the deep laminae, primarily the stratum album intermedium. Trigeminal fibers were present in the SC by the day of birth, and at this time, they terminated mainly in the deep layers. However, labelled fibers also extended into the superficial laminae (the stratum griseum superficiale and stratum opticum) reaching as far as the SC surface. Trigeminal projections to the superficial SC laminae were visible as late as postnatal day (P-) 6, but were absent by P-8. During the period when V axons were present in the superficial SC laminae, they could not be detected in the dorsal lateral geniculate nucleus.     

A novel role for cilia‐dependent sonic hedgehog signaling during submandibular gland development

Background: Submandibular glands (SMGs) are specialized epithelial structures which generate saliva necessary for mastication and digestion. Loss of SMGs can lead to inflammation, oral lesions, fungal infections, problems with chewing/swallowing, and tooth decay. Understanding the development of the SMG is important for developing therapeutic options for patients with impaired SMG function. Recent studies have suggested Sonic hedgehog (Shh) signaling in the epithelium plays an integral role in SMG development; however, the mechanism by which Shh influences gland development remains nebulous. Results: Using the Kif3a^f/f;Wnt1‐Cre ciliopathic mouse model to prevent Shh signal transduction by means of the loss of primary cilia in neural crest cells, we report that mesenchymal Shh activity is necessary for gland development. Furthermore, using a variety of murine transgenic lines with aberrant mesenchymal Shh signal transduction, we determine that loss of Shh activity, by means of loss of the Gli activator, rather than gain of Gli repressor, is sufficient to cause the SMG aplasia. Finally, we determine that loss of the SMG correlates with reduced Neuregulin1 (Nrg1) expression and lack of innervation of the SMG epithelium. Conclusions: Together, these data suggest a novel mechanistic role for mesenchymal Shh signaling during SMG development. Developmental Dynamics 247:818–831, 2018. © 2018 Wiley Periodicals, Inc.     

The role of the thyroid gland in the regulation of cell division

Summary Experiments carried out on white rats have shown that the complete extirpation of the thyroid gland decreases mitotic activity in different tissues. Injection of thyrotropic hormone increased thyroid gland and mitotic activity. The latter is also increased in the case of accessory illumination of animals. This reaction proceeds by means of the thyroid gland activation; after the blockade of thyroid gland with methylthiouracil, accessory illumination of mice does not bring about an increase of cell division in the tissues.Presented by D. N. Nasonov, Active Member of the Academy of Medical Sciences, USSR     

Secretion of kallikrein and its role in vasodilatation in the submaxillary gland

1. The effects of parasympathetic (chorda) and sympathetic nerve stimulation on the concentration and output of kallikrein secreted in saliva from the cat's submaxillary gland were compared. Sympathetic stimulation always produced a much higher concentration (up to 500 times) and output (up to 390 times) of kallikrein than parasympathetic stimulation. In the dog, in which sympathetic nerve stimulation produces little or no secretion from the submaxillary gland, there was also a marked increase in the secretion of kallikrein when sympathetic was superimposed on parasympathetic secretion. This effect did not occur, however, in the rabbit's submaxillary gland.2. It was possible to deplete the cat's submaxillary gland of kallikrein, either by ligation of the duct for several days or by duct ligation and sympathetic nerve stimulation, so that it was undetectable either in the gland or in saliva after stimulation of the chorda. Such glands, nevertheless, responded to chorda stimulation with a normal atropine-resistant vasodilatation.3. There is a close parallelism between the rate of secretion of salvia and vasodilatation over a range of frequencies of chorda stimulation, but the output (and concentration) of kallikrein in saliva is distinctly different for the same frequencies of nerve stimulation.4. Our results are consistent with the view that vasodilator nerves exist in the parasympathetic nerves to the submaxillary gland. We suggest that they are cholinergic in nature despite the fact that chorda vasodilatation is resistant to atropine. It is further suggested that neither the kallikrein-kinin system nor adrenergic vasodilator nerve fibres play a significant role in chorda vasodilatation.