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Prostaglandins regulate various functions throughout the gastrointestinal system. Their biosynthesis depends on cyclooxygenase isoforms, named COX-1 and COX-2. The initial hypothesis that COX-2 is an inducible enzyme has been challenged and its constitutive expression in the stomach has been established. In this study, an immunohistochemical analysis was performed to evaluate the distribution and cellular localization of COX-2 in normal human colon. Colonic surgical specimens were processed for COX-2, protein HuC/HuD, neurofilament, S-100 protein and CD117/c-kit immunodetection. COX-2 protein was found to be constitutively expressed in the colonic wall: detectable amounts were localized in mucosal, submucosal and muscular layers, mainly in the neuromuscular compartment. In particular, COX-2 was expressed in muscularis mucosae, submucosal ganglia, longitudinal muscle layer and myenteric ganglia, the neurons of which displayed different degrees of immunostaining. Intramuscular interstitial cells of Cajal, regarded as important sites for the regulation of enteric neuromuscular activity, were also partly COX-2 immunoreactive. This study provides a detailed mapping of COX-2 expression in human colon, and allows better understanding of the roles played by this isoenzyme in gut physiology. [ABSTRACT FROM AUTHOR]

In mouse the cannabinoid receptor 2 (CB2) agonists L768242 and (+)-AM1241, at doses of 30 mg/kg i.p. and 1 and 3 mg/kg i.v., respectively, reduced the second phase of nocifensive behaviors elicited by formalin intraplantar injection. This effect was counteracted by the selective CB2 antagonist SR144528 (1 mg/kg i.p.). In rat (+)-AM1241 (3 and 6 mg/kg i.v.) and L768242 (30 mg/kg i.p.) reduced allodynia elicited by L5–L6 spinal nerve ligation. SR144528 reverted these effects, supporting a CB2-mediated action. To clarify the mechanisms underlying these effects we investigated CB2 gene expression and function in the nervous system. CB2 mRNA was expressed in spinal cord and dorsal root ganglia (DRG) of both sham and neuropathic rats and was up-regulated in the ipsilateral spinal cord of neuropathic rats. Expression studies demonstrated the presence of CB2 mRNA in culture of spinal cord microglia. A biomarker, CGRP, was used to investigate modulation of DRG primary afferents by CB2 agonists. Both L768242 and (+)-AM1241 dose dependently (EC50 of 3.6 and 4.5 nm, respectively) reduced capsaicin-induced calcitonin gene-related peptide (CGRP) release. Coadministration of SR144528 resulted in a rightforward shift (pKB 8.1 and 8.2 for (+)-AM1241 and L768242, respectively) of the dose–response curve. Experiments on capsaicin-induced CGRP release in tissue from CB1–/– mice ruled out a CB1-mediated effect. These results confirm that CB2 is present in the central nervous system and suggest that CB2 agonists may elicit their analgesic effect by acting not only at non-neuronal peripheral sites but also at neural level, making CB2 an attractive target for chronic pain treatment. [ABSTRACT FROM AUTHOR]

Rat sciatic nerve axons express capsaicin, proton and heat sensitivity and respond to stimulation with a Ca2+-dependent and graded calcitonin gene-related peptide (CGRP) release. In this study we demonstrate that similar functions, including capsaicin-induced CGRP release, are to be found in the desheathed sciatic nerve of the mouse. We have morphologically investigated the mechanisms of this axonal release in regions away from the active zones of synapses. Capsaicin receptor 1 (TRPV1) and CGRP immunostaining was performed using electron microscopic visualization. TRPV1 was identified in the axoplasm and inside vesicles—presumably on axonal transport—as well as in considerable quantity in the axonal plasma membrane of unmyelinated nerve fibers. Most of the unmyelinated axons were immunopositive for CGRP and in unstimulated nerves CGRP-containing vesicles almost entirely filled the axoplasm. After capsaicin stimulation (10-6 M for 5 min), the fibers appeared depleted of CGRP with only few vesicles remaining as well as some residual staining of the axoplasm. In addition a large number of vesicles were fused with the axonal membrane, forming classical exocytotic figures—the ω structures—lined with CGRP immunoreactive product.These results present morphological evidence for the distribution of TRPV1 along unmyelinated axons in peripheral nerve and also provide the first demonstration of vesicular neuropeptide exocytosis along unmyelinated axons in peripheral nerve. [Copyright &y& Elsevier]

Real-time/performed electroacoustic music is currently facing a serious sustainability problem. Although historically its production is very recent, several technological revolutions have gone by in the meantime. Most of these works can hardly be performed because the technology involved has gone lost since the first realization, and no long-standing notational precaution was ever taken. This paper (first published in 2005 and translated in Italian for the first time) presents some typical case studies and introduces some techniques that might lead to a partial -- when not completely adequate -- solution to the sustainability problem. [ABSTRACT FROM AUTHOR]

A recent Italian study examined the immune response to the COVID-19 vaccine among psoriatic patients receiving biological therapy. The study included 346 psoriatic patients and 151 controls who received two doses of the vaccine and were tested for antibodies. The results showed that both groups had a strong antibody response, with no significant difference between patients and controls. Mild adverse events were reported by about one-fourth of participants, and no serious adverse events were reported. The study also found that the type of vaccine administered was associated with antibody levels, with higher levels observed in those vaccinated with Janssen and lower levels in those vaccinated with AstraZeneca. However, the number of subjects who received these vaccines was limited. The study suggests that COVID-19 vaccinations are effective and safe for psoriatic patients undergoing biological treatments. [Extracted from the article]

Emerging evidence indicates a nociceptive role of vagal afferents. A distinct oesophageal innervation in the rat, with muscular and mucosal afferents travelling predominantly in the recurrent (RLN) and superior laryngeal nerve (SLN), respectively, enabled characterization of mucosal afferents with nociceptive properties, using novel isolated oesophagus–nerve preparations. SLN and RLN single-fibre recordings identified 55 and 14 units, respectively, with none conducting faster than 8.7 m s−1. Mucosal response characteristics in the SLN distinguished mechanosensors ( n= 13), mechanosensors with heat sensitivity (18) from those with cold sensitivity (19) and a mechanoinsensitive group (5). The mechanosensitive fibres, all slowly adapting, showed a unimodal distribution of mechanical thresholds (1.4–128 mN, peak ∼5.7 mN). No difference in response characteristics of C and Aδ fibres was encountered. Mucosal proton stimulation (pH 5.4 for 3 min), mimicking gastro-oesophageal reflux disease (GORD), revealed in 31% of units a desensitizing response that peaked around 20 s and faded within 60 s. Cold stimulation (15°C) was proportionally encoded but the response showed slow adaptation. In contrast, the noxious heat (48°C) response showed no obvious adaptation with discharge rates reflecting the temperature's time course. Polymodal (69%) mucosal units, > 30% proton sensitive, were found in each fibre category and were considered nociceptors; they are tentatively attributed to vagal nerve endings type I, IV and V, previously morphologically described. All receptive fields were mapped and the distribution indicates that the posterior upper oesophagus may serve as a ‘cutbank’, detecting noxious matters, ingested or regurgitated, and triggering nocifensive reflexes such as bronchoconstriction in GORD. [ABSTRACT FROM AUTHOR]

Background: Few studies have compared the efficacy of switching to adalimumab in the real‐life setting in plaque psoriasis patients. Objective: To evaluate the effect of adalimumab in psoriasis patients previously treated with other biologics. Methods: In this multicentre study, psoriasis patients (N = 262) treated with an anti‐TNF‐alpha agent, ustekinumab or naïve to biologics then switched to adalimumab were included. Disease severity was assessed by the Psoriasis Area and Severity Index (PASI) at baseline and after 3, 6, 12, 24 and 36 months. The association between clinical risk factors and achievement of PASI response was evaluated by logistic regression. Results: Adalimumab treatment resulted in a decrease in PASI (15.1 ± 6.2 at baseline vs. 2.7 ± 4.8 at 6 months, P < 0.0001), regardless of previous biologic treatment. Furthermore, adalimumab allowed 92.5%, 79% and 56% of patients to achieve PASI response (PASI 50, 75 and 90, respectively) and complete remission (PASI 100 response) in 48.4% of patients, by 6 months and maintained over 3 years, independent of prior biologic treatment. The absence of metabolic syndrome, dyslipidemia, hypertension and lower PASI and lower age at baseline was associated with achievement of PASI response at 3, 6 and 12 months, whereas at later time points (24 and 36 months), PASI 90 and PASI 100 response was associated with diagnosis of psoriasis/psoriatic arthritis. Conclusion: Adalimumab was effective at reducing PASI score over 3 years, irrespective of whether patients were biologic naïve or previously treated with a TNF‐alpha or IL‐12/23 inhibitor. [ABSTRACT FROM AUTHOR]

Abstract: Hidradenitis suppurativa (HS) is a chronic disorder of terminal follicular epithelium in the apocrine gland‐bearing areas. The long term therapy is based mainly on topical and/or systemic antibiotic use that could result in antibiotic resistance. The aim of our study was to present the real‐life experience based on the efficacy and tolerability of a novel lotion containing triethyl‐citrate, ethyl‐linoleate, and g‐peptide‐10 in the treatment of mild to moderate HS that has already shown effectiveness in acne treatment. This was an open‐label study on 30 patients of both sexes affected by HS. Patients were divided into two groups: 15 with Hurley I and 15 with Hurley II–III. The subjects were treated with the topical lotion, three‐times‐daily for eight weeks, with control at 4 (T1) and eight weeks (T2). Any other concomitant treatment (both topical and/or systemic) was avoided during study period. Improvement was observed in both Sartorius score grading system and inflammatory and noninflammatory lesion counts. The novel lotion has proved to be effective and well‐tolerated topical agent alone or in association with other topical and/or systemic tratments in HS, without side effects [ABSTRACT FROM AUTHOR]

Introduction The mainstay therapy for Parkinson's disease (PD) relies on L-3,4-dihydroxyphenylalanine (L-DOPA) plus a DOPA-decarboxylase inhibitor. However, their effects on colonic dysmotility and inflammation observed in PD are undetermined. This study examined the effects of L-DOPA plus benserazide (BE) on colonic motility and inflammation in rats with central nigrostriatal dopaminergic denervation. Methods Neurodegeneration was induced by 6-hydroxydopamine (6-OHDA) injection into the medial forebrain bundle (MFB). 6-OHDA animals were treated orally with L-DOPA/BE for 28 days, starting 28 days after 6-OHDA injection. At the end of treatment, in vivo colonic transit was evaluated by a radiologic assay. Electrically stimulated (ES) cholinergic contractions were recorded in vitro from colonic preparations, while acetylcholine release was measured in the incubation medium. Choline acetyltransferase (ChAT) and glial fibrillary acidic protein (GFAP) expression as well as eosinophil and mast cell density were examined in the colonic wall by immunohistochemistry. Colonic TNF and IL-1β levels were also assayed. Results 6-OHDA animals displayed: 1) decrease in in vivo colonic transit; 2) impairment of ES-stimulated cholinergic contractions; 3) decreased acetylcholine release from myenteric nerves; 4) decrease in ChAT and increase in GFAP myenteric immunopositivity; 5) increase in eosinophil and mast cell density; 6) increase in TNF and IL-1β levels. Treatment with L-DOPA/BE elicited an improvement of in vivo and in vitro colonic motor activity, a normalization of acetylcholine release, ChAT immunopositivity, as well as pro-inflammatory cytokine patterns, ganglionic GFAP levels, eosinophil and mast cell density. Conclusion Under dopaminergic nigrostriatal denervation, treatment with L-DOPA/BE ameliorated colonic motility through a normalization of myenteric cholinergic neurotransmission, along with an improvement of colonic inflammation. [ABSTRACT FROM AUTHOR]

On March 2020, COVID-19 has been declared as a pandemic emergency by World Health Organization (WHO). One paediatric patient had asthma (7%) and another patient had celiac disease and allergy. Twenty-three patients were adults with age ranging from 35 to 72 years, eight patients (35%) were male and 15 (65%) female, 12/23 (52%) had no previous disease. [Extracted from the article]

Background and Purpose The COX isoforms ( COX-1, COX-2) regulate human gut motility, although their role under pathological conditions remains unclear. This study examines the effects of COX inhibitors on excitatory motility in colonic tissue from patients with diverticular disease ( DD). Experimental Approach Longitudinal muscle preparations, from patients with DD or uncomplicated cancer (controls), were set up in organ baths and connected to isotonic transducers. Indomethacin ( COX-1/ COX-2 inhibitor), SC-560 ( COX-1 inhibitor) or DFU ( COX-2 inhibitor) were assayed on electrically evoked, neurogenic, cholinergic and tachykininergic contractions, or carbachol- and substance P ( SP)-induced myogenic contractions. Distribution and expression of COX isoforms in the neuromuscular compartment were assessed by RT-PCR, Western blot and immunohistochemical analysis. Key Results In control preparations, neurogenic cholinergic contractions were enhanced by COX inhibitors, whereas tachykininergic responses were blunted. Carbachol-evoked contractions were increased by indomethacin or SC-560, but not DFU, whereas all inhibitors reduced SP-induced motor responses. In preparations from DD patients, COX inhibitors did not affect electrically evoked cholinergic contractions. Both indomethacin and DFU, but not SC-560, decreased tachykininergic responses. COX inhibitors did not modify carbachol-evoked motor responses, whereas they counteracted SP-induced contractions. COX-1 expression was decreased in myenteric neurons, whereas COX-2 was enhanced in glial cells and smooth muscle. Conclusions and Implications In control colon, COX-1 and COX-2 down-regulate cholinergic motility, whereas both isoforms enhance tachykininergic motor activity. In the presence of DD, there is a loss of modulation by both COX isoforms on the cholinergic system, whereas COX-2 displays an enhanced facilitatory control on tachykininergic contractile activity. [ABSTRACT FROM AUTHOR]

Abstract: Fiber mesh scaffolds were recently investigated in tissue engineering as possible support for stem cell growth and differentiation, in order to repair lesion areas in clinical practice. In particular, the literature is focused on fiber mesh scaffolds constituted of biocompatible and resorbable polymeric structures, like poly(l-lactic acid) (PLLA). However, as regards the study of constructs constituted of PLLA microfibers and cells, only quantitative and SEM analyses were reported, lacking histological analysis. Histological evaluation of these constructs could give important information about cellular distribution in the scaffold, cell–scaffold interactions and extracellular matrix production. The purpose of our study was to find a valid method to analyze PLLA microfiber/cell constructs from both histological and histochemical angles. Biodegradable non-woven fiber meshes were prepared using hollow microfibers, based on PLLA. We first evaluated different embedding methods useable for histological analysis and the results showed that among the paraffin, Killik, and acrylic resin the only suitable medium was the latter. Then we employed the acrylic resin to embed the constructs made up of PLLA microfibers and bone marrow-derived human mesenchymal stromal cells, which we then analyzed with Toluidine Blue, PAS and Alcian Blue staining. These constructs, previously analyzed for cell viability by MTT and CCK-8 tests, showed viable/proliferating cells until 6 weeks of culture. The stainings performed on constructs confirmed viability data obtained with SEM and MTT/CCK-8 and supplied other information on the cell behaviors such as the distribution and organization onto the scaffold and the production of extracellular matrix molecules. In conclusion, this methodological study mainly suggests a suitable method to analyze PLLA microfiber/cell constructs, at the same time confirming and enriching the literature data on the compatibility between PLLA microfibers and hMSCs. [Copyright &y& Elsevier]

β3-Adrenoceptor agonists protect against experimental gastric ulcers. We investigated the effects of the β3-adrenoceptor agonist SR58611A on 2,4-dinitrobenzene sulphonic acid-induced colitis in rats and analysed the expression of β3-adrenoceptors in the colonic wall. SR58611A was administered orally (1–10 mg kg−1) for 7 days, starting the day before induction of colitis. Colitis was assessed by macroscopic and histological scores, tissue myeloperoxidase activity, interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) levels. Reverse transcription-polymerase chain reaction and immunohistochemical analysis were used to examine the expression of β3-adrenoceptors. SR58611A significantly reduced the severity of colitis as well as the tissue levels of TNF-α, IL-1β and IL-6. Colitis was associated with a decreased expression of β3-adrenoceptor mRNA in the mucosal/submucosal layer of distal colon and this reduction was not affected by SR58611A. Immunohistochemical analysis revealed β3-adrenoceptors within the muscularis externa, in myenteric neurons and nerve fibres and in the submucosa. β3-Adrenoceptor immunoreactivity was decreased in inflamed tissues compared to controls, particularly in the myenteric plexus; this reduction was counteracted by SR58611A. Amelioration of experimental colitis by the selective β3-adrenoceptor agonist SR58611A suggests that β3-adrenoceptors may represent a therapeutic target in gut inflammation. [ABSTRACT FROM AUTHOR]

The new combination between the nucleoside analogue gemcitabine and the cholesterol-lowering drug fluvastatin was investigated in vitro and in vivo on the human pancreatic tumour cell line MIAPaCa-2. The present study demonstrates that fluvastatin inhibits proliferation, induces apoptosis in pancreatic cancer cells harbouring a p21ras mutation at codon 12 and synergistically potentiates the cytotoxic effect of gemcitabine. The pharmacologic activities of fluvastatin are prevented by administration of mevalonic acid, suggesting that the shown inhibition of geranyl-geranylation and farnesylation of cellular proteins, including p21rhoA and p21ras, plays a major role in its anticancer effect. Fluvastatin treatment also indirectly inhibits the phosphorylation of p42ERK2/mitogen-activated protein kinase, the cellular effector of ras and other signal transduction peptides. Moreover, fluvastatin administration significantly increases the expression of the deoxycytidine kinase, the enzyme required for the activation of gemcitabine, and simultaneously reduces the 5'-nucleotidase, responsible for deactivation of gemcitabine, suggesting a possible additional role of these enzymes in the enhanced cytotoxic activity of gemcitabine. Finally, a significant in vivo antitumour effect on MIAPaCa-2 xenografts was observed with the simultaneous combination of fluvastatin and gemcitabine, resulting in an almost complete suppression and a marked delay in relapse of tumour growth. In conclusion, the combination of fluvastatin and gemcitabine is an effective cytotoxic, proapoptotic treatment in vitro and in vivo against MIAPaCa-2 cells by a mechanism of action mediated, at least in part, by the inhibition of p21ras and rhoA prenylation. The obtained experimental findings might constitute the basis for a novel translational research in humans. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to establish a method for light microscopical immunohistochemical localization of the small G protein RhoA on specimens treated and embedded for routine transmission electron microscopy. There are advantages in antigen immunolocalization on resin semi-thin sections compared to cryostat or paraffin sections: the preservation of morphological details, the well-defined immunoprecipitate localization and the possibility to correlate the immunohistochemical results with those obtained by electron microscope on neighbouring sections. These advantages are particularly useful for the subcellular localization of low molecular weight proteins such as RhoA, a small G protein able to cycle from the inactive cytoplasmic form to the plasma membrane-bound active form. [Copyright &y& Elsevier]

Hidradenitis suppurativa (HS) is a chronic relapsing disorder of the apocrine gland affecting mainly areas subjected to friction (e.g. the axillae, groin, perineum and medial aspects of the thighs). This condition can be linked to different comorbidities: autoimmune and inflammatory disease, hormone‐related disorders, obesity and the metabolic syndrome, as well as rare syndromes such as Bazex–Dupré–Christol, Down's, KID, PAPASH, PASS, PASH, and SAPHO syndromes, or Dowling–Degos disease. We report a case of severe HS in a patient with Trisomy 1q;13, a very rare cytogenetic anomaly characterized by severe anomalies including dysmorphisms, multiple congenital malformations, heart defects and intellectual disability. [ABSTRACT FROM AUTHOR]

Background Symptoms of digestive dysfunction in patients with Parkinson's disease ( PD) occur at all stages of the disease, often preceding the onset of central motor symptoms. On the basis of these PD-preceding symptoms it has been proposed that PD could initiate in the gut, and that the presence of alpha-synuclein aggregates, or Lewy bodies in the enteric nervous system might represent one of the earliest signs of the disease. Following this hypothesis, much research has been focused on the digestive tract to unravel the mechanisms underlying the onset and progression of PD, with particular attention to the role of alterations in enteric neurotransmission in the pathophysiology of intestinal motility disturbances. There is also evidence suggesting that the development of central nigrostriatal neurodegeneration is associated with the occurrence of gut inflammation, characterized by increments of tissue pro-inflammatory markers and oxidative stress, which might support conditions of bowel neuromotor abnormalities. Purpose The present review intends to provide an integrated and critical appraisal of the available knowledge on the alterations of enteric neuromuscular pathways regulating gut motor activity both in humans and preclinical models of PD. Moreover, we will discuss the possible involvement of neuro-immune mechanisms in the pathophysiology of aberrant gastrointestinal gut transit and neuromuscular activity in the small and large bowel. [ABSTRACT FROM AUTHOR]