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1.
Acta Oncol ; 60(10): 1241-1249, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34279175

ABSTRACT

BACKGROUND: Prediction models are useful tools in the clinical management of colon cancer patients, particularly when estimating the recurrence rate and, thus, the need for adjuvant treatment. However, the most used models (MSKCC, ACCENT) are based on several decades-old patient series from clinical trials, likely overestimating the current risk of recurrence, especially in low-risk groups, as outcomes have improved over time. The aim was to develop and validate an updated model for the prediction of recurrence within 5 years after surgery using routinely collected clinicopathologic variables. MATERIAL AND METHODS: A population-based cohort from the Swedish Colorectal Cancer Registry of 16,134 stage I-III colon cancer cases was used. A multivariable model was constructed using Cox proportional hazards regression. Three-quarters of the cases were used for model development and one quarter for internal validation. External validation was performed using 12,769 stage II-III patients from the Norwegian Colorectal Cancer Registry. The model was compared to previous nomograms. RESULTS: The nomogram consisted of eight variables: sex, sidedness, pT-substages, number of positive and found lymph nodes, emergency surgery, lymphovascular and perineural invasion. The area under the curve (AUC) was 0.78 in the model, 0.76 in internal validation, and 0.70 in external validation. The model calibrated well, especially in low-risk patients, and performed better than existing nomograms in the Swedish registry data. The new nomogram's AUC was equal to that of the MSKCC but the calibration was better. CONCLUSION: The nomogram based on recently operated patients from a population registry predicts recurrence risk more accurately than previous nomograms. It performs best in the low-risk groups where the risk-benefit ratio of adjuvant treatment is debatable and the need for an accurate prediction model is the largest.


Subject(s)
Colonic Neoplasms , Neoplasm Recurrence, Local , Area Under Curve , Cohort Studies , Colonic Neoplasms/epidemiology , Colonic Neoplasms/pathology , Humans , Neoplasm Recurrence, Local/epidemiology , Neoplasm Staging , Nomograms , Retrospective Studies
2.
J Synchrotron Radiat ; 28(Pt 1): 64-70, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-33399553

ABSTRACT

Protein dynamics contribute to protein function on different time scales. Ultrafast X-ray diffraction snapshots can visualize the location and amplitude of atom displacements after perturbation. Since amplitudes of ultrafast motions are small, high-quality X-ray diffraction data is necessary for detection. Diffraction from bovine trypsin crystals using single femtosecond X-ray pulses was recorded at FemtoMAX, which is a versatile beamline of the MAX IV synchrotron. The time-over-threshold detection made it possible that single photons are distinguishable even under short-pulse low-repetition-rate conditions. The diffraction data quality from FemtoMAX beamline enables atomic resolution investigation of protein structures. This evaluation is based on the shape of the Wilson plot, cumulative intensity distribution compared with theoretical distribution, I/σ, Rmerge/Rmeas and CC1/2 statistics versus resolution. The FemtoMAX beamline provides an interesting alternative to X-ray free-electron lasers when studying reversible processes in protein crystals.


Subject(s)
Crystallography, X-Ray , Trypsin/chemistry , Animals , Cattle , Macromolecular Substances/chemistry , Photons , Synchrotrons
3.
Struct Dyn ; 7(5): 054303, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32984435

ABSTRACT

Time-resolved optical pump/X-ray probe experiments are often used to study structural dynamics. To ensure high temporal resolution, it is necessary to monitor the timing between the X-ray pulses and the laser pulses. The transition from a crystalline solid material to a disordered state in a non-thermal melting process can be used as a reliable timing monitor. We have performed a study of the non-thermal melting of InSb in single-shot mode, where we varied the sample temperature in order to determine the conditions required for repetitive melting. We show how experimental conditions affect the feasibility of such a timing tool.

4.
Phys Rev Lett ; 124(10): 105701, 2020 Mar 13.
Article in English | MEDLINE | ID: mdl-32216426

ABSTRACT

This study shows that initial atomic velocities as given by thermodynamics play an important role in the dynamics of phase transitions. We tracked the atomic motion during nonthermal laser-induced melting of InSb at different initial temperatures. The ultrafast atomic motion following bond breaking can in general be governed by two mechanisms: the random velocity of each atom at the time of bond breaking (inertial model), and the forces acting on the atoms after bond breaking. The melting dynamics was found to follow the inertial model over a wide temperature range.

5.
Struct Dyn ; 6(2): 024501, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30915389

ABSTRACT

We have studied strain wave generation in graphite induced by an intense ultrashort laser pulse. The study was performed in the intensity regime above the ablation threshold of graphite. The aim was to maximize the strain and, thus, also the internal pressure (stress). Laser pulses with a 1 ps temporal duration melt the surface of graphite resulting in a molten material which initially exists at the solid density. As the molten material expands, a compressive strain wave starts propagating into the crystal below the molten layer. The strain pulse was studied with time-resolved X-ray diffraction. At a temporal delay of 100 ps after laser excitation, we observed >10% compressive strain, which corresponds to a pressure of 7.2 GPa. This strain could be reproduced by hydrodynamic simulations, which also provided a temperature map as a function of time and depth.

6.
Ned Tijdschr Tandheelkd ; 125(11): 593-601, 2018 11.
Article in Dutch | MEDLINE | ID: mdl-30457580

ABSTRACT

Evidence-based reviews of drugs causing medication-induced salivary gland dysfunction, such as xerostomia (sensation of oral dryness) and subjective sialorrhea are lacking. To compile a list of medicaments that influence salivary gland function, electronic databases were searched for relevant articles published up to June 2013. A total of 269 papers out of 3,867 records located satisfied the inclusion criteria (relevance, quality of methodology, strength of evidence). A total of 56 active substances with a higher level of evidence and 50 active substances with a moderate level of evidence of causing salivary gland dysfunction are described in this article. While xerostomia was a commonly reported outcome, the objective effect on salivary secretion was rarely measured. Xerostomia was, moreover, mostly reported as a negative side effect instead of the intended effect of that drug. A comprehensive list of medications having documented effects on salivary gland function or symptoms was compiled, which may assist practitioners in assessing patients who complain of dry mouth while taking medications.


Subject(s)
Salivary Glands/drug effects , Xerostomia/etiology , Humans
7.
J Clin Virol ; 108: 90-95, 2018 11.
Article in English | MEDLINE | ID: mdl-30267999

ABSTRACT

BACKGROUND: Acute respiratory infections (ARI) are a leading cause of morbidity and mortality worldwide. There is a need to demonstrate the clinical impact of using the new, rapid and sensitive molecular assays in prospectively designed studies. OBJECTIVES: To study the impact on medical management of a rapid molecular assay in patients with respiratory infections. STUDY DESIGN: A prospective, randomized, non-blinded study was performed in patients presenting to the Emergency Department during two respiratory seasons (2016-2017). Diagnosis was performed by FilmArray Respiratory Panel (FilmArray-RP) or by immunofluorescence assay (IFA). RESULTS: A total of 432 patients (156 children and 276 adults) were analyzed. Diagnosis with FilmArray-RP was associated with significant changes in medical management including withholding antibiotic prescriptions (OR:15.52, 95%CI:1.99-120.83 in adults and OR:12.23, 95%CI:1.56-96.09 in children), and reduction in complementary studies in children (OR:9.64, 95%CI:2.13-43.63) compared to IFA. Decrease in oseltamivir prescriptions was significantly higher in adults in the FilmArray-RP group (p = 0.042; OR:1.19, 95%CI:0.51-2.79) compared to adults managed with IFA. Diagnostic yield was significantly higher by FilmArray-RP (81%) than by IFA (31%)(p < 0.001). The median time from sample collection to reporting was 1 h 52 min by FilmArray-RP and 26 h by IFA (p < 0.001). CONCLUSIONS: The high respiratory viruses' detection rate and availability of results within two hours when using FilmArray-RP were associated with decreases in antibiotic prescriptions and complementary studies and more accurate use of oseltamivir.


Subject(s)
Acute Disease , Respiratory Tract Infections/diagnosis , Virus Diseases/diagnosis , Viruses/isolation & purification , Adolescent , Adult , Aged , Child , Child, Preschool , Emergency Service, Hospital/statistics & numerical data , Female , Fluorescent Antibody Technique , Humans , Inappropriate Prescribing/prevention & control , Infant , Male , Middle Aged , Multiplex Polymerase Chain Reaction , Oligonucleotide Array Sequence Analysis , Oseltamivir/therapeutic use , Prospective Studies , Respiratory Tract Infections/virology , Virus Diseases/drug therapy , Viruses/classification , Young Adult
8.
Med Oral Patol Oral Cir Bucal ; 23(5): e552-e559, 2018 Sep 01.
Article in English | MEDLINE | ID: mdl-30148471

ABSTRACT

BACKGROUND: Salivary gland function is controlled by the salivary reflex, whose efferent arm is composed by the parasympathetic and the sympathetic divisions of the autonomic nervous system. Parenchymal injury is the main salivary gland involvement of Sjögren's syndrome and head and neck radiotherapy, but neural damage has been reported as well. Recently an intraoral device for electrostimulation of the lingual nerve in vicinity to the lower third molar has been introduced. At this point this nerve carries efferent fibers for the innervation of the submandibular, sublingual and several minor salivary glands and afferent fibers of the salivary reflex. Therefore, excitation of these fibers potentially leads to increased secretion of all salivary glands. Thus, the study objective was to assess whether comprehensive neural activation by electrostimulation of the lingual nerve carries the potential to induce the regeneration of damaged salivary glands. MATERIAL AND METHODS: The device was tested on three patients with no collectable resting and stimulated secretion of saliva during a double blind, sham controlled period of two months and nine open-label months. RESULTS: All three subjects developed the capacity to spit saliva, not only in direct response to the electrostimulation but also after free intervals without electrostimulation. In addition, their symptoms of dry mouth severity and frequency improved. CONCLUSIONS: This recovery is probably due to the combined effect of increase in secretory functional gland mass and regain of nervous control of the secretory elements and blood vessels. Both are phenomena that would contribute to gland regeneration.


Subject(s)
Electric Stimulation Therapy/instrumentation , Lingual Nerve , Regeneration , Salivary Glands/physiology , Xerostomia/therapy , Aged , Cross-Over Studies , Electric Stimulation Therapy/methods , Equipment Design , Female , Humans , Male , Middle Aged
9.
J Oral Rehabil ; 45(9): 730-746, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29878444

ABSTRACT

Saliva is a complex fluid produced by 3 pairs of major salivary glands and by hundreds of minor salivary glands. It comprises a large variety of constituents and physicochemical properties, which are important for the maintenance of oral health. Saliva not only protects the teeth and the oropharyngeal mucosa, it also facilitates articulation of speech, and is imperative for mastication and swallowing. Furthermore, saliva plays an important role in maintaining a balanced microbiota. Thus, the multiple functions provided by saliva are essential for proper protection and functioning of the body as a whole and for the general health. A large number of diseases and medications can affect salivary secretion through different mechanisms, leading to salivary gland dysfunction and associated oral problems, including xerostomia, dental caries and fungal infections. The first part of this review article provides an updated insight into our understanding of salivary gland structure, the neural regulation of salivary gland secretion, the mechanisms underlying the formation of saliva, the various functions of saliva and factors that influence salivary secretion under normal physiological conditions. The second part focuses on how various diseases and medical treatment including commonly prescribed medications and cancer therapies can affect salivary gland structure and function. We also provide a brief insight into how to diagnose salivary gland dysfunction.


Subject(s)
Mastication/physiology , Oral Health , Saliva/physiology , Salivary Glands/physiology , Salivation/physiology , Xerostomia/physiopathology , Humans , Saliva/chemistry , Salivary Glands/anatomy & histology
10.
J Synchrotron Radiat ; 25(Pt 2): 570-579, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29488939

ABSTRACT

The FemtoMAX beamline facilitates studies of the structural dynamics of materials. Such studies are of fundamental importance for key scientific problems related to programming materials using light, enabling new storage media and new manufacturing techniques, obtaining sustainable energy by mimicking photosynthesis, and gleaning insights into chemical and biological functional dynamics. The FemtoMAX beamline utilizes the MAX IV linear accelerator as an electron source. The photon bursts have a pulse length of 100 fs, which is on the timescale of molecular vibrations, and have wavelengths matching interatomic distances (Å). The uniqueness of the beamline has called for special beamline components. This paper presents the beamline design including ultrasensitive X-ray beam-position monitors based on thin Ce:YAG screens, efficient harmonic separators and novel timing tools.

11.
Struct Dyn ; 4(5): 051102, 2017 Sep.
Article in English | MEDLINE | ID: mdl-29085849

ABSTRACT

We have studied an X-ray switch based on a gold coated indium antimonide crystal using time-resolved X-ray diffraction and demonstrated that the switch could reduce the pulse duration of a 100 ps X-ray pulse down to 20 ps with a peak reflectivity of 8%. We have used a dynamical diffraction code to predict the performance of the switch, which was then confirmed experimentally. The experiment was carried out at the FemtoMAX beamline at the short-pulse facility of the MAX IV laboratory. The performance and limitation of the switch are discussed in terms of acoustic transport properties between the two materials and the electron transport properties of gold.

12.
J Physiol Pharmacol ; 67(1): 111-9, 2016 Feb.
Article in English | MEDLINE | ID: mdl-27010900

ABSTRACT

Our recent ultrastructural study of human parotid glands revealed that the melatonin receptors, MT1 and MT2, are localised in the plasma cell membranes of acinar and ductal cells but also, and intriguingly, predominantly in acinar secretory granules, giving rise to the working hypothesis that secretory granules are a part of a transcytotic transport system for melatonin. To put this hypothesis to the test in rat parotid glands, anaesthetised animals were exposed to a high melatonin dose (3 mg/kg per hour), infused intravenously over two hours and aiming to stimulate a glandular melatonin-receptor-dependent intracellular transport system, if any. Thirty minutes later, the right parotids were removed. Pre-stimulation, left parotid gland tissue was removed to serve as (untreated) controls. Gland tissues were processed for the gold post-embedding technique and for western blot analysis. In untreated glands, on transmission electron microscope images, melatonin receptors displayed a distribution pattern similar to that in human parotids, i.e. here, too, the receptors were principally associated with the acinar secretory granules. In melatonin- treated glands, the number of granules associated with the MT1 receptor was twice that in untreated glands, despite the same total granule number in the two glands. Moreover, the density of gold particles showing MT1-receptor immunoreactivity associated with granules in melatonin-treated glands was 2.5 times that in untreated glands. The number of MT1 receptors associated with the granule membrane was about three times higher in melatonin-treated glands than in untreated glands, while the number of MT1 receptors inside the granules was about twice that in untreated glands. The immunoblotting of membrane-enriched samples showed that the MT1-receptor expression was about three times that of untreated glands. When it came to the MT2 receptor, no changes were observed. Melatonin itself thus exerts dynamic effects on its MT1 receptor, which may reflect an adaptive receptor-linked carrier system for melatonin, delivering - upon gland stimulation - melatonin to the saliva by exocytosis.


Subject(s)
Melatonin/metabolism , Parotid Gland/metabolism , Receptor, Melatonin, MT1/metabolism , Animals , Cell Membrane/metabolism , Female , Rats , Rats, Sprague-Dawley , Receptor, Melatonin, MT2/metabolism , Saliva/metabolism
13.
Oral Dis ; 22(5): 365-82, 2016 Jul.
Article in English | MEDLINE | ID: mdl-26602059

ABSTRACT

The aim of this paper was to perform a systematic review of the pathogenesis of medication-induced salivary gland dysfunction (MISGD). Review of the identified papers was based on the standards regarding the methodology for systematic reviews set forth by the World Workshop on Oral Medicine IV and the PRISMA statement. Eligible papers were assessed for both the degree and strength of relevance to the pathogenesis of MISGD as well as on the appropriateness of the study design and sample size. A total of 99 papers were retained for the final analysis. MISGD in human studies was generally reported as xerostomia (the sensation of oral dryness) without measurements of salivary secretion rate. Medications may act on the central nervous system (CNS) and/or at the neuroglandular junction on muscarinic, α-and ß-adrenergic receptors and certain peptidergic receptors. The types of medications that were most commonly implicated for inducing salivary gland dysfunction were those acting on the nervous, cardiovascular, genitourinary, musculoskeletal, respiratory, and alimentary systems. Although many medications may affect the salivary flow rate and composition, most of the studies considered only xerostomia. Thus, further human studies are necessary to improve our understanding of the association between MISGD and the underlying pathophysiology.


Subject(s)
Salivary Gland Diseases/chemically induced , Salivary Glands/drug effects , Drug-Related Side Effects and Adverse Reactions , Humans , Oral Medicine/methods , Salivary Gland Diseases/pathology , Salivary Glands/pathology
14.
Arch Oral Biol ; 60(6): 863-74, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25841068

ABSTRACT

This narrative review of the functions of saliva was conducted in the PubMed, Embase and Web of Science databases. Additional references relevant to the topic were used, as our key words did not generate references which covered all known functions of saliva. These functions include maintaining a moist oral mucosa which is less susceptible to abrasion, and removal of micro-organisms, desquamated epithelial cells, leucocytes and food debris by swallowing. The mucins form a slimy coating on all surfaces in the mouth and act as a lubricant during such processes as mastication, formation of a food bolus, swallowing and speaking. Saliva provides the fluid in which solid tastants may dissolve and distributes tastants around the mouth to the locations of the taste buds. The hypotonic unstimulated saliva facilitates taste recognition. Salivary amylase is involved in digestion of starches. Saliva acts as a buffer to protect oral, pharyngeal and oesophageal mucosae from orally ingested acid or acid regurgitated from the stomach. Saliva protects the teeth against acid by contributing to the acquired enamel pellicle, which forms a renewable lubricant between opposing tooth surfaces, by being supersaturated with respect to tooth mineral, by containing bicarbonate as a buffer and urea and by facilitating clearance of acidic materials from the mouth. Saliva contains many antibacterial, antiviral and antifungal agents which modulate the oral microbial flora in different ways. Saliva also facilitates the healing of oral wounds. Clearly, saliva has many functions which are needed for proper protection and functioning of the human body.


Subject(s)
Saliva/physiology , Cariogenic Agents , Humans , Lubrication , Mouth Mucosa/physiology , Olfactory Perception/physiology , Saliva/chemistry , Saliva/metabolism , Salivary Proteins and Peptides/physiology , Secretory Rate , Taste Perception/physiology , Tooth Diseases/prevention & control , Wound Healing/physiology
15.
J Physiol Pharmacol ; 66(6): 847-53, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26769834

ABSTRACT

In vivo animal studies show that pentagastrin, cholecystokinin and melatonin cause the secretion and synthesis of salivary proteins. Melatonin occurs in large amounts in the gut and is released into the blood on food intake. In vitro experiments suggest that pentagastrin exerts secretory activity in human salivary glands, as judged by ultrastructural changes, reflecting secretion, and an actual protein output. Currently, it is hypothesised that melatonin induces secretory exocytotic events in the human parotid gland. Human parotid tissues were exposed to a high single concentration of melatonin in vitro, processed for high resolution scanning electron microscopy and then assessed morphometrically with the emphasis on the membrane of the intercellular canaliculi, a site of protein secretion. Compared with controls and in terms of density, the melatonin-exposed parotid tissues displayed increases in protrusions (signalling anchored granules) and microbuds (signalling membrane recycling and/or vesicle secretion) and decreases in microvilli (signalling cytoskeletal re-arrangement related to exocytosis), phenomena abolished or very largely reduced by the melatonin receptor blocker, luzindole. In conclusion, acinar serous cells of parotid tissue displayed in vitro exocytotic activity to melatonin, signalling protein secretion. Whether, under physiological conditions, melatonin influences the secretion of human parotid glands remains to be explored, however.


Subject(s)
Melatonin/pharmacology , Parotid Gland/drug effects , Adult , Aged , Exocytosis/drug effects , Female , Humans , Male , Microscopy, Electron, Transmission , Middle Aged , Parotid Gland/cytology , Parotid Gland/metabolism , Parotid Gland/ultrastructure
16.
Oral Dis ; 21(2): 216-23, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24725136

ABSTRACT

OBJECTIVE: The parasympathetic transmitters vasoactive intestinal peptide (VIP) and substance P (SP) are secretagogues in salivary glands of animals. Currently, we hypothesise that in human salivary glands, these neuropeptides and the VIP-related peptide histidine methionine (PHM) also exert secretory actions, reflected morphologically by exocytosis of acinar protein/glycoprotein-storing granules. MATERIALS AND METHODS: Submandibular and parotid gland tissues, exposed in vitro to VIP and PHM, and SP, respectively, were examined by light and transmission electron microscopy. For comparison, the response to in vitro stimulation of isoproterenol, phenylephrine and carbachol was examined. Moreover, the peptidergic innervation of the glands was examined by immunohistochemistry. RESULTS: Vasoactive intestinal peptide- and PHM-immunoreactive nerves were in close proximity to acini and ducts in the two glands, while these elements lacked a SP-positive innervation. While no morphological changes occurred in response to SP (parotid glands), VIP and PHM administration (submandibular glands) caused conspicuous acinar degranulation accompanied by luminal space broadening. In the two glands, both α1 - and ß-adrenergic receptor stimulation and muscarinic receptor stimulation caused similar changes as to VIP/PHM, although to varying extent. CONCLUSIONS: Vasoactive intestinal peptide and PHM, but not SP, are likely transmitters in the parasympathetic control of salivary (protein) secretion in humans.


Subject(s)
Neuropeptides/pharmacology , Peptide PHI/pharmacology , Salivary Glands/drug effects , Salivary Glands/metabolism , Substance P/pharmacology , Vasoactive Intestinal Peptide/pharmacology , Adult , Aged , Carbachol/pharmacology , Female , Humans , In Vitro Techniques , Isoproterenol/pharmacology , Male , Middle Aged , Phenylephrine/pharmacology , Saliva/metabolism , Salivary Glands/cytology , Salivary Glands/innervation
17.
Invest New Drugs ; 32(6): 1063-70, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25052234

ABSTRACT

Oncolytic virotherapy is a promising novel form of cancer treatment, but the therapeutic efficiency needs improvement. A potential strategy to enhance the therapeutic effect of oncolytic viruses is to use infectious nucleic acid as therapeutic agent to initiate an oncolytic infection, without administrating infectious viral particles. Here we demonstrate improved viral replication activation efficiency when transfecting cells with 5' end authentic in vitro transcribed enterovirus RNA as compared to genomic RNA with additional non-genomic 5' nucleotides generated by conventional cloning methods. We used echovirus 5 (E5) as an oncolytoc model virus due to its ability to replicate in and completely destroy five out of six colon cancer cell lines and kill artificial colon cancer tumors (HT29 spheroids), as shown here. An E5 infectious cDNA clone including a hammerhead ribozyme sequence was used to generate in vitro transcripts with native 5' genome ends. In HT29 cells, activation of virus replication is approximately 20-fold more efficient for virus genome transcripts with native 5' genome ends compared to E5 transcripts generated from a standard cDNA clone. This replication advantage remains when viral progeny release starts by cellular lysis 22 h post transfection. Hence, a native 5' genomic end improves infection activation efficacy of infectious nucleic acid, potentially enhancing its therapeutic effect when used for cancer treatment. The clone design with a hammerhead ribozyme is likely to be applicable to a variety of oncolytic positive sense RNA viruses for the purpose of improving the efficacy of oncolytic virotherapy.


Subject(s)
Enterovirus B, Human/physiology , Oncolytic Viruses/physiology , RNA, Viral/genetics , Animals , CHO Cells , Cell Line , Cell Line, Tumor , Chlorocebus aethiops , Colonic Neoplasms/therapy , Cricetulus , Enterovirus B, Human/genetics , Genome, Viral , Humans , Oncolytic Virotherapy , Oncolytic Viruses/genetics , Spheroids, Cellular , Transfection , Virus Replication
18.
Oral Dis ; 20(8): 796-802, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24245711

ABSTRACT

OBJECTIVE: Amisulpride is reported to inhibit clozapine-induced sialorrhea. Preclinically, clozapine evokes muscarinic-M1-type-mediated secretion that, however, amisulpride does not reduce. Instead, amisulpride, without causing any overt secretion per se, enhances both nerve- and autonomimetic-evoked salivation by unknown mechanism(s). Hypothesizing that amisulpride prepares the gland for secretion, we looked for ultrastructural events indicating secretory activity in intercellular canaliculi of serous/seromucous cells, that is, density increase in protrusions (reflecting anchored granules) and in microbuds (reflecting recycling membranes and/or vesicle secretion) and decrease in microvilli (reflecting the cytoskeletal re-arrangement related to exocytosis). MATERIAL AND METHODS: Rat parotid and submandibular glands were exposed to amisulpride in vivo or in vitro. Glands were processed for transmission electron and scanning electron microscopy and then morphometrically assessed. RESULTS: Cells were packed with secretory granules. The density of protrusions increased in both glands, whereas significant and parallel changes in microvilli and microbuds occurred only in parotid glands, and in vitro. CONCLUSIONS: Amisulpride induced ultrastructural signs of secretory activity but to varying extent; in submandibular glands, in contrast to parotid glands, changes were not brought beyond the granular anchoring stage. Amisulpride may provide an overall readiness for secretion that will result in augmented responses to agonists, a phenomenon of potential interest in dry-mouth treatment.


Subject(s)
Antipsychotic Agents/pharmacology , Salivary Glands/drug effects , Sulpiride/analogs & derivatives , Amisulpride , Animals , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Rats , Rats, Wistar , Salivary Glands/ultrastructure , Sulpiride/pharmacology
19.
Oral Dis ; 20(3): e90-6, 2014 Apr.
Article in English | MEDLINE | ID: mdl-23731177

ABSTRACT

OBJECTIVE: The parasympathetic transmitter vasoactive intestinal peptide (VIP) increases salivary gland blood flow and evokes protein secretion and, in some species, such as rats, a small fluid secretion. It interacts synergistically with muscarinics for protein and fluid output. Human salivary acini are supplied with VIP-containing nerves. We hypothesise that VIP and clozapine, acting together, evoke a volume of saliva greater than the sum of those induced by each drug given separately. It was further considered whether, in the current test situation, circulatory events influenced the magnitude of the secretory response. MATERIAL AND METHODS: Saliva from parotid glands deprived of their autonomic innervation, and saliva and blood from innervated submandibular glands were collected in adrenoceptor antagonist-pretreated pentobarbitone-anaesthetised rats. Initially, the individual and then the combined effects of intravenous doses of VIP and clozapine were established. RESULTS: The submandibular volume response to the combination was 2-3 times higher, while blood pressure and glandular blood flow did not differ from those to VIP alone. The synergism occurred independent of nerves as shown in denervated parotid glands. CONCLUSIONS: From the current preclinical data, we speculate that VIP of parasympathetic origin, by its synergistic interaction with clozapine, may contribute to the clozapine (muscarinic M1-receptor)-induced sialorrhoea in schizophrenics.


Subject(s)
Antipsychotic Agents/adverse effects , Clozapine/adverse effects , Sialorrhea/chemically induced , Vasoactive Intestinal Peptide/physiology , Animals , Female , Parasympathetic Nervous System/metabolism , Parotid Gland/drug effects , Parotid Gland/metabolism , Rats , Rats, Sprague-Dawley , Submandibular Gland/drug effects , Submandibular Gland/metabolism , Vasoactive Intestinal Peptide/biosynthesis
20.
J Anat ; 223(5): 519-24, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23998562

ABSTRACT

The hormone melatonin influences oral health through a variety of actions, such as anti-inflammatory, anti-oxidant, immunomodulatory and antitumour. Many of these melatonin functions are mediated by a family of membrane receptors expressed in the oral epithelium and salivary glands. Using immunoblotting and immunohistochemistry, recent studies have shown that the melatonin membrane receptors, MT1 and MT2, are present in rat and human salivary glands. To date, no investigation has dealt with the ultrastructural distribution of the melatonin receptors. This was the aim of the present study, using the immunogold method applied to the human parotid gland. Reactivity to MT1 and, with less intensity, to MT2 appeared in the secretory granules of acinar cells and in the cytoplasmic vesicles of both acinar and ductal cells. Plasma membranes were also stained, albeit slightly. The peculiar intracytoplasmic distribution of these receptors may indicate that there is an uptake/transport system for melatonin from the circulation into the saliva.


Subject(s)
Parotid Gland/ultrastructure , Receptor, Melatonin, MT1/analysis , Receptor, Melatonin, MT2/analysis , Acinar Cells/chemistry , Adult , Aged , Female , Humans , Immunohistochemistry , Male , Microscopy, Electron, Transmission , Middle Aged , Parotid Gland/chemistry
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