Acute radiotherapy-associated oral pain may promote tumor growth at distant sites.

Introduction: Patients developing acute radiotherapy induced dermatitis or oral mucositis commonly experience pain. When severe, this radiotherapy-associated pain (RAP) can necessitate treatment breaks; unfortunately, in a variety of cancers, prolongation of the radiotherapy course has been associated with early cancer relapse and/or death. This is often attributed to accelerated repopulation, but it is unknown whether pain or pain signaling constituents might alter tumor behavior and hasten metastatic disease progression. We studied this by testing the hypothesis that severe acute RAP at one site can hasten tumor growth at a distant site. Methods: Mice underwent single fraction tongue irradiation (27 Gy, or 0 Gy "sham" control) to induce severe glossitis. At the time of maximal oral RAP, one of three luciferase-transfected tumor cell lines were injected via tail vein (4T1, B16F10, MOC2; each paired to their syngeneic host: BALB/c or C57BL/6); tumor burden was assessed via in vivo transthoracic bioluminescence imaging and ex vivo pulmonary nodule quantification. Survival was compared using Kaplan-Meier statistics. Results: Tongue irradiation and resultant RAP promoted lung tumor growth of 4T1-Luc2 cells in BALB/c mice. This effect was not a result of off-target radiation, nor an artefact of environmental stress caused by standard (subthermoneutral) housing temperatures. RAP did not affect the growth of B16F10-Luc2 cells, however, C57BL/6 mice undergoing tail vein injection of MOC2-Luc2 cells at the time of maximal RAP experienced early lung tumor-attributable death. Lung tumor growth was normalized when RAP was reduced by treatment with resiniferatoxin (300 µg/kg, subcutaneously, once). Discussion: This research points towards radiation-induced activation of capsaicin-responsive (TRPV1) neurons as the cause for accelerated growth of tumors at distant (unirradiated) sites.

Systematic review on the anxiolytic and hypnotic effects of flower extracts in in vivo pre-clinical studies published from 2010 to 2020.

Anxiety disorders are prevalent conditions in the world population, whose standard approaches include pharmacotherapy, psychotherapy, and combinations of these interventions. Different classes of psychopharmaceuticals are recommended as the first line of drugs to treat these disorders, which can have several adverse effects, treatment resistance, dependence, and drug-drug interactions making it necessary to search for new therapeutic agents. In particular, diazepam (DZP), a prototype drug from the group of benzodiazepines, has been commonly used and evaluated for its efficacy and safety in different anxiety disorders in clinical trials. DZP is also the most widely used reference standard in in vivo pharmacological assays of natural compounds. However, translating the results obtained in different rodent species and physiological anxiety tests instead of psychopathological animal models that can be of clinical application remains challenging. A systematic review of scientific articles published between 2010 and 2020 that included in vivo pre-clinical tests to define the anxiolytic, sedative and/or hypnotic effect of flower extracts is proposed. PRISMA and Rayyan were used for the selection of studies using four databases (Pubmed, Scopus, Web of Science, and QInsight), using the keywords: "Animals," "Anxiolytic," "Diazepam," "Elevated Plus Maze," "Flower Extracts," "Insomnia," "In vivo," "Mice," "Open Field Test," "Pre clinical" and "Sedative." The characteristics of anxiety studies in animal models, other studies related to locomotor activity, and the hypnotic effect of the extracts were compiled. Twenty-four articles were included, 21 of them performed the animal model of anxiety-like behavior of the elevated plus maze, seven the open field test, and six the light-dark box test. The locomotor activity was evaluated in 10 studies after the administration of the extracts to the animals to define their sedative effect, where only one defined that the extract (Matricaria chamomilla) had a sedative effect. The plants declared with this type of activity were Achyranthes aspera, Alcea aucheri, Brassica nigra, Cananga odorata, Carthamus tinctorius, Chrysanthemum indicum, Citrus aurantium, Couroupita guianensis, Echium amoenum, Erythrina berteroana, Gardenia jasminoides, Hibiscus tilliaceus, Lavandula officinalis, Lawsonia inermis, Matricaria chamomilla, Melia azedarach, Nerium oleander, Passiflora incarnata, Plumeria rubra, Salix aegyptiaca, Syzygium aromaticum, Tagetes erecta, Tilia americana. Although this review showed that some flower extracts have an anxiolytic effect as effective as diazepam, their therapeutic utility in anxiety disorders remains to be extensively demonstrated. Hence, more reliable and predictive behavioral tests and appropriate strategies for the experimental designs are needed to obtain more conclusive evidence with clinical significance.

"Reactance inversion" at low frequencies during lung function measurement by impulse oscillometry in children with persistent asthma.

BACKGROUND: Small airway dysfunction (SAD) in asthma can be measured by impulse oscillometry (IOS). Usually, the reactance should decrease with decreases in frequency oscillation. Sometimes an upward shift of the curve at low frequencies can be observed together with lower than expected reactance values. The actual value of the reactance at 5 Hz (X5) is calculated by the Sentry Suite application of the Jaeger Master screen iOS system™, providing the corrected X5 parameter (CX5). Our hypothesis is that correction of X5 is common in persistent asthma and it correlates better than X5 with the IOS parameters for evaluating SAD. METHODS: In this transversal study, we evaluated 507 children (3-18 years old) using IOS-spirometry (Sentry Suite, Vyntus®). Resistance of all airways (R5), reactance area (AX), resonant frequency (Fres), X5, CX5, difference between R5 and R20 (D5-20), and spirometry parameters were analyzed. Reactance inversion and CX5 prevalence by age range was determined. The mean IOS-Spyrometry values in children with and without CX5 were compared, and correlations with each IOS-spirometry parameter in the age groups were performed. RESULTS: CX5 was found in 83.5% of preschool children, 66.2% of schoolchildren, and 43.3% of adolescents (p < 0.001). The means of R5, AX, and D5-20 were significantly higher and FEV1 was significantly lower in children with CX5 (p < 0.05). In all ages, CX5 correlated better than X5 with IOS-spirometry parameters. CONCLUSION: Reactance inversion and CX5 are frequent in asthmatic children, decrease with age, and correlate more closely than X5 with other IOS-spirometry parameters for evaluating SAD.

Irradiation of the Normal Murine Tongue Causes Upregulation and Activation of Transient Receptor Potential (TRP) Ion Channels.

Signal transduction at sensory neurons occurs via transmembrane flux of cations, which is largely governed by the transient receptor potential (TRP) family of ion channels. It is unknown whether TRP channel activation contributes to the pain that accompanies radiation-induced oral mucositis. This study sought to characterize changes in TRP channel expression and function that occur in the locally irradiated tissues and afferent neurons of mice. Female CD-1 mice received single high-dose (27 Gy) tongue irradiation, or sham irradiation. Animals were euthanized either before overt glossitis developed (days 1 and 5 postirradiation), when glossitis was severe (day 11), or after mice had recovered (days 21 and 45). Tongue irradiation caused upregulation of the Trpv1 gene in trigeminal ganglia (TG) neurons. Other TRP genes (Trpv2, Trpv4, Trpa1, Trpm8) and Gfrα3 (which acts upstream of several TRP channels) were also upregulated in TGs and/or tongue tissue, in response to radiation. Ex vivo calcium imaging experiments demonstrated that the proportions of TG neurons responding to histamine (an activator of TRPV1, TRPV4 and TRPA1), TNF-α (an activator of TRPV1, TRPV2 and TRPV4), and capsaicin (a TRPV1 agonist), were increased as early as one day after tongue irradiation; these changes persisted for at least 21 days. In a subsequent experiment, we found that genetic deletion of TRPV1 mitigated weight loss (a surrogate marker of pain severity) in mice with severe glossitis. The results intimate that various TRP channels, and TRPV1 in particular, should be explored as analgesic targets for patients experiencing pain after oral irradiation.

Proteomic profiling of proteins in the dorsal horn of the spinal cord in dairy cows with chronic lameness.

Chronic lameness affects bovine welfare and has a negative economic impact in dairy industry. Moreover, due to the translational gap between traditional pain models and new drugs development for treating chronic pain states, naturally occurring painful diseases could be a potential translational tool for chronic pain research. We therefore employed liquid chromatography tandem mass spectrometry (LC-MS/MS) to stablish the proteomic profile of the spinal cord samples from lumbar segments (L2-L4) of chronic lame dairy cows. Data were validated and quantified through software tool (Scaffold® v 4.0) using output data from two search engines (SEQUEST® and X-Tandem®). Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) analysis was performed to detect proteins interactions. LC-MS/MS identified a total amount of 177 proteins; of which 129 proteins were able to be quantified. Lame cows showed a strong upregulation of interacting proteins with chaperone and stress functions such as Hsp70 (p < 0.006), Hsc70 (p < 0.0079), Hsp90 (p < 0.015), STIP (p > 0.0018) and Grp78 (p <0.0068), and interacting proteins associated to glycolytic pathway such as; γ-enolase (p < 0.0095), α-enolase (p < 0.013) and hexokinase-1 (p < 0.028). It was not possible to establish a clear network of interaction in several upregulated proteins in lame cows. Non-interacting proteins were mainly associated to redox process and cytoskeletal organization. The most relevant down regulated protein in lame cows was myelin basic protein (MBP) (p < 0.02). Chronic inflammatory lameness in cows is associated to increased expression of stress proteins with chaperone, metabolism, redox and structural functions. A state of endoplasmic reticulum stress and unfolded protein response (UPR) might explain the changes in protein expression in lame cows; however, further studies need to be performed in order to confirm these findings.

Mechanical/thermal sensitivity and superficial temperature in the stump of long-term tail-docked dairy cows.

BACKGROUND: Tail docking of dairy cows is a painful procedure that affects animal welfare level. The aims of this study were first to evaluate the response to mechanical and thermal stimulation, and second to determine the superficial temperature of the stump of tail-docked dairy cows. METHODS: One hundred and sixty-four dairy cows were enrolled. From these, 133 cows were assigned to the tail-docked (TD) group and 31 cows were selected as control animals. The following sensory assessments to evaluate pain in tail-docked cows were performed. Sensitivity of the tail region in both groups of animals was evaluated using a portable algometer. Cold and heat sensitivity assessment was performed using a frozen pack (0 °C) and warm water (45 °C), respectively. Pinprick sensitivity was evaluated using a Wartenberg neurological pinwheel. Superficial temperature was evaluated using a thermographic camera. All sensory assessments and superficial temperature were evaluated in the ventral surface of the tail stump (TD) and tail (C). RESULTS: Pressure pain threshold was lower in TD cows (5.97 ± 0.19 kg) compared to control cows (11.75 ± 0.43 kg). Heat and cold sensitivity was higher in the TD cows compared to control cows with 29% and 23% of TD cows responding positively, respectively. Similarly, after pinprick sensitivity test was performed, 93% of TD cows elicited a positive response to stimulation. Tail-docked cows had lower superficial temperature (26.4 ± 0.27 °C) compared to control cows (29.9 ± 0.62 °C). DISCUSSION: Pressure pain threshold values in both groups of animals were higher than those previously reported for TD pigs, sows and cows. In contrast, pinprick stimulation evaluates the presence of punctate mechanical hyperalgesia/allodynia, usually related to traumatic nerve injury, and this association may reveal that it is possible that these animals developed a disorder associated to the development of a tail stump neuroma and concurrent neuropathic pain, previously reported in TD lambs, pigs and dogs. Thermal sensitivity showed that TD cows responded positively to heat and cold stimulation. These findings suggest that long-term TD cows could be suffering hyperalgesia/allodynia, which may be indicative of chronic pain. Lower superficial temperature in the stump may be associated to sympathetic fiber sprouting in the distal stump, which can lead to vasoconstriction and lower surface temperatures. Further studies are needed in order to confirm neuroma development and adrenergic sprouting.

Microglia and astrocyte activation in the spinal cord of lame horses.

OBJECTIVE: To determine the microglial and astrocyte response to painful lameness in horses. STUDY DESIGN: Ionized calcium binding adaptor molecule 1 (Iba-1) and glial fibrillary acidic protein (GFAP) expression, cell density and morphology were determined through immunofluorescence within the dorsal horn of equine spinal cord. ANIMALS: A total of five adult horses with acute or chronic unilateral lameness, previously scheduled for euthanasia. METHODS: Musculoskeletal lameness was evaluated in five horses through visual evaluation according to clinical guidelines. Spinal cord samples were obtained immediately after euthanasia, and distal limb lesions were confirmed through dissection and radiography. Iba-1 immunostaining was used for detection and characterization of dorsal horn microglia. GFAP was used for immunostaining of dorsal horn astrocytes. Iba-1 and GFAP labeled cells were quantified in the dorsal horn, and intensity of fluorescence was compared between the ipsi- and contralateral dorsal horn to the affected limb, and between dorsal horn segments of all horses. RESULTS: Iba-1 expression was higher in the ipsilateral dorsal horn of the affected limb in contrast to the contralateral side dorsal horn. GFAP markers did not demonstrate increased astrocytic activity on the dorsal horn ipsilateral side to the distal limb lesion of affected horses. Horses with acute lameness predominantly had a spherical shape microglial phenotype, while cells from chronic lameness cases had variable morphology. Astrocytes evidenced small somas and large processes in both acute and chronic lameness, with higher GFAP localization in the main branches. As in the case of rodents, the localization of microglia and astrocytes in horses was mainly situated within laminae I, II and III. CONCLUSIONS AND CLINICAL RELEVANCE: Iba-1 and GFAP are functional and morphological markers of spinal microglial cells and astrocytes in horses with lameness.

Impacto de la cirugía mamaría en la lactancia materna / The impact of breast surgery on breastfeeding

La lactancia materna para la mujer es un periodo vital, el que es influido por diferentes factores, entre estos, está el antecedente de cirugía mamaria. El propósito de esta revisión es explorar, en la evidencia disponible, el impacto que tienen los implantes mamarios y la reducción mamaria en el amamantamiento. Esto, con el fin de apoyar el trabajo con las mujeres en el proceso de lactancia materna e informar previamente a las usuarias cómo estas cirugías podrían afectar su proceso. Con respecto a las características de la cirugía, hay diferencias en los efectos que puede tener en la producción de leche, según: el tipo de cirugía, tipo de abordaje y el sitio de incisión, que puede afectar a corto y largo plazo. Debido a que existe evidencia heterogénea con respecto al impacto de la cirugía mamaria en la lactancia materna, toma un rol importante considerar en la evaluación este antecedente en la mujer, para realizar un buen diagnóstico. Ante todo, es importante el apoyo y guía educativa, tanto prenatal como en el puerperio, para empoderar a las mujeres en la toma de decisiones y el manejo de su lactancia materna, previo a la cirugía y durante el proceso de lactancia materna. Para lograr esto se necesita personal de salud capacitado, que pueda intervenir en esta realidad, informado, con la mejor evidencia disponible.

Breastfeeding is a vital period for women and it's influenced by different factors such as breast surgery. The purpose of this review is to explore available evidence on the impact that some breast surgeries (breast implants or breast reduction) have on breastfeeding. This is to support the breastfeeding process in this women, and also to inform them how these surgeries could affect on their breastfeeding process. There are several factors related to surgery that can influence on the breastfeeding process, such as the type of approach, the incision siteand, in the case of the implant, where it is located, which may affect short or long term. Because there are not enough studies, and there is also heterogeneous evidence regarding the impact of breast surgery on breastfeeding, it is important the educational support be given both prior to surgery and during the pre and postnatal phases. To achieve this the trained health professionals need to be informed and with the best evidence available related to the breastfeeding process.

Immunofluorescence characterization of spinal cord dorsal horn microglia and astrocytes in horses.

The role of glial cells in pain modulation has recently gathered attention. The objective of this study was to determine healthy spinal microglia and astrocyte morphology and disposition in equine spinal cord dorsal horns using Iba-1 and GFAP/Cx-43 immunofluorescence labeling, respectively. Five adult horses without visible wounds or gait alterations were selected. Spinal cord segments were obtained post-mortem for immunohistochemical and immunocolocalization assays. Immunodetection of spinal cord dorsal horn astrocytes was done using a polyclonal goat antibody raised against Glial Fibrillary Acidic Protein (GFAP) and a polyclonal rabbit antibody against Connexin 43 (Cx-43). For immunodetection of spinal cord dorsal horn microglia, a polyclonal rabbit antibody against a synthetic peptide corresponding to the C-terminus of ionized calcium-binding adaptor molecule 1 (Iba-1) was used. Epifluorescence and confocal images were obtained for the morphological and organizational analysis. Evaluation of shape, area, cell diameter, cell process length and thickness was performed on dorsal horn microglia and astrocyte. Morphologically, an amoeboid spherical shape with a mean cell area of 92.4 + 34 µm2 (in lamina I, II and III) was found in horse microglial cells, located primarily in laminae I, II and III. Astrocyte primary stem branches (and cellular bodies to a much lesser extent) are mainly detected using GFAP. Thus, double GFAP/Cx-43 immunolabeling was needed in order to accurately characterize the morphology, dimension and cell density of astrocytes in horses. Horse and rodent astrocytes seem to have similar dimensions and localization. Horse astrocyte cells have an average diameter of 56 + 14 µm, with a main process length of 28 + 8 µm, and thickness of 1.4 + 0.3 µm, mainly situated in laminae I, II and III. Additionally, a close association between end-point astrocyte processes and microglial cell bodies was found. These results are the first characterization of cell morphology and organizational aspects of horse spinal glia. Iba-1 and GFAP/Cx-43 can successfully immune-label microglia and astrocytes respectively in horse spinal cords, and thus reveal cell morphology and corresponding distribution within the dorsal horn laminae of healthy horses. The conventional hyper-ramified shape that is normally visible in resting microglial cells was not found in horses. Instead, horse microglial cells had an amoeboid spherical shape. Horse protoplasmic astroglia is significantly smaller and structurally less complex than human astrocytes, with fewer main GFAP processes. Instead, horse astrocytes tend to be similar to those found in rodent's model, with small somas and large cell processes. Microglia and astrocytes were found in the more superficial regions of the dorsal horn, similarly to that previously observed in humans and rodents. Further studies are needed to demonstrate the molecular mechanisms involved in the neuron-glia interaction in horses.