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PURPOSE: Recent research has highlighted the mechanotransducer PIEZO2 as a crucial factor in lower urinary tract function, demonstrating associations with bladder compliance (BC), bladder wall thickening, and elevated bladder pressure. We explored the hypothesis that PIEZO2 expression may be associated with lower urinary tract dysfunction in men with bladder outlet obstruction (BOO) due to benign prostatic hyperplasia (BPH). METHODS: The study included a consecutive series of patients undergoing open prostatectomy for BPH at our hospital between September 2014 and January 2016. All participants underwent comprehensive preoperative evaluations, including urodynamic assessments. During prostatectomy, a full-thickness fragment of the bladder wall was obtained for subsequent PIEZO2 gene expression analysis. Cadaveric organ donors served as the control group. RESULTS: PIEZO2 expression was downregulated in the detrusor muscle of men with BPH compared to the control group. Among patients with BPH, those experiencing urinary retention and requiring an indwelling catheter exhibited significantly lower PIEZO2 messenger RNA (mRNA) expression than patients capable of spontaneous voiding. PIEZO2 mRNA expression was similar in men with and without detrusor overactivity. Additionally, a positive correlation was found between PIEZO2 mRNA expression levels and BC. CONCLUSION: Our findings indicate that PIEZO2 is downregulated in the detrusor muscle of men with BPH, particularly in those experiencing urinary retention and those with reduced BC. These results suggest a potential role for PIEZO2 in BOOinduced bladder dysfunction. Further research is required to clarify the role of PIEZO mechanotransducers in the bladder and to explore their therapeutic implications.

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This paper proposes a low-cost electronic system for estimating ground reaction forces (GRF) during human gait. The device consists of one master node and two slave nodes. The master node sends instructions to slave nodes that sample and store data from two force insoles located at the participant's feet. These insoles are equipped with 14 piezo-resistive FlexiForce A301 sensors (FSR). The slave nodes are attached to the ankles and feet of each participant. Subsequently, the start command is transmitted through the master node, which is connected to the USB port of a personal computer (PC). Once the walking session is completed, the information obtained by the slave nodes can be downloaded by accessing the access point generated by these devices through Wi-Fi communication. The GRF estimation system was validated with force platforms (BTS Bioengineering P6000, Italy), giving on average a fit measure equal to 68 . 71 % ± 4 . 80 % in dynamic situations. Future versions of this device are expected to increase this fit by using machine learning models.

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Chagas disease vectors can ingest several times their own volume in blood with each meal. This ad libitum feeding causes an intense process of diuresis, inducing the insect to eliminate a large quantity of urine and faeces. To ensure diuresis, the speed of circulation of the haemolymph is increased. The Triatominae circulatory system is quite simple, including the dorsal vessel, which pumps haemolymph in an anterograde direction. The return is caused by peristaltic contractions of the anterior midgut. Triatominae insects can spend several weeks without feeding, meaning that most of the time, the insect is in a resting condition. Although the mechanisms controlling the circulation of the haemolymph during post-prandial diuresis have been largely analysed, the mechanisms controlling it during resting conditions are poorly understood. In this study, we analysed several canonical pathways (i.e. L-type VGCC, GPCR, RyR, IP3R) and a novel system represented by the recently characterized Piezo proteins. Our results show that during the resting condition, haemolymph circulation depends on a cross-talk between myogenic activity, inhibitory and stimulatory cellular messengers, and Piezo proteins. This report also unveils for the first time the existence of a putative Piezo protein in Hemiptera.

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Background: The intracytoplasmic sperm injection (ICSI) technique has low efficiency in cattle. This has mainly been attributed to the oocyte activation failure due to oocyte and/or sperm factors. Aim: Our aim was to evaluate the effect of conventional ICSI and Piezo-ICSI with bull or human sperm on bovine oocyte activation and embryo development and to assess its relationship with the phospholipase C zeta (PLCɀ) activity of both species. Methods: In vitro matured bovine oocytes were randomly divided into five groups and were fertilized as follows: conventional ICSI using bovine sperm with chemical activation (control), conventional ICSI using bovine sperm, Piezo-ICSI using bovine sperm, conventional ICSI using human sperm, and Piezo-ICSI using human sperm. PLCɀ activity was determined in bull and human sperm samples. Results: Within the groups using bull sperm, the oocytes fertilized by conventional ICSI had the lowest values of 2 pronuclei (PN) formation and cleavage, Piezo-ICSI increased both percentages and ICSI + chemical activation presented the highest 2 PN, cleavage, and blastocyst rates (p < 0.05). Within the groups using human sperm, the oocytes fertilized by Piezo-ICSI presented higher 2 PN and cleavage rates than those activated by conventional ICSI (p < 0.05). Piezo-ICSI with human sperm increased bovine oocyte activation as much as conventional ICSI + chemical activation with bovine sperm (p < 0.05). Higher values of PLCɀ activity were found in human sperm compared with bovine sperm (p < 0.05). Conclusion: Our results suggest that the higher stability of the bovine sperm in combination with its relatively low content of PLCɀ impairs bovine oocyte activation after ICSI.

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This article describes a novel minimally invasive technique for bilateral sagittal split osteotomy (BSSO) that aims to reduce surgical trauma while maintaining bone overlap and rigid internal fixation for proper consolidation of the bone segments. The technique involves a small vestibular mucoperiosteal incision made on the lateral aspect of the mandible between the first and second molars, enabling a standard ramus split, surgical segment movement, and miniplate fixation. A retrospective evaluation of 67 consecutive patients who underwent BSSO using this protocol showed favorable split of the mandible with no unfavorable splits or non-union. Patients were discharged from hospital within an average of 17 h with minimal postoperative complications. This technique provides good surgical visualization with a very small incision and allows standard BSSO surgery without difficulty.

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Asthma is one of the main non-communicable chronic diseases and affects a huge portion of the population. It is a multifactorial disease, classified into several phenotypes, being the allergic the most frequent. The pathophysiological mechanism of asthma involves a Th2-type immune response, with high concentrations of allergen-specific immunoglobulin E, eosinophilia, hyperreactivity and airway remodeling. These mechanisms are orchestrated by intracellular signaling from effector cells, such as lymphocytes and eosinophils. Ion channels play a fundamental role in maintaining the inflammatory response on asthma. In particular, transient receptor potential (TRP), stock-operated Ca2+ channels (SOCs), Ca2+-activated K+ channels (IKCa and BKCa), calcium-activated chloride channel (TMEM16A), cystic fibrosis transmembrane conductance regulator (CFTR), piezo-type mechanosensitive ion channel component 1 (PIEZO1) and purinergic P2X receptor (P2X). The recognition of the participation of these channels in the pathological process of asthma is important, as they become pharmacological targets for the discovery of new drugs and/or pharmacological tools that effectively help the pharmacotherapeutic follow-up of this disease, as well as the more specific mechanisms involved in worsening asthma.

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PIEZO1 is a mechanosensitive cation channel implicated in shear stress-mediated endothelial-dependent vasorelaxation. Since altered shear stress patterns induce a pro-inflammatory endothelial environment, we analyzed transcriptional profiles of human endothelial cells to determine the effect of altered shear stress patterns and subsequent prooxidant and inflammatory conditions on PIEZO1 and mechanosensitive-related genes (MRG). In silico analyses were validated in vitro by assessing PIEZO1 transcript levels in both the umbilical artery (HUAEC) and vein (HUVEC) endothelium. Transcriptional profiling showed that PIEZO1 and some MRG associated with the inflammatory response were upregulated in response to high (15 dyn/cm2) and extremely high shear stress (30 dyn/cm2) in HUVEC. Changes in PIEZO1 and inflammatory MRG were paralleled by p65 but not KLF or YAP1 transcription factors. Similarly, PIEZO1 transcript levels were upregulated by TNF-alpha (TNF-α) in diverse endothelial cell types, and pre-treatment with agents that prevent p65 translocation to the nucleus abolished PIEZO1 induction. ChIP-seq analysis revealed that p65 bonded to the PIEZO1 promoter region, an effect increased by the stimulation with TNF-α. Altogether this data showed that NF-kappa B activation via p65 signaling regulates PIEZO1 expression, providing a new molecular link for prooxidant and inflammatory responses and mechanosensitive pathways in the endothelium.

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Sperm sexing is a technology that can generate great economic benefits in the animal production sector. Techniques such as sex-sorting promise over 90% accuracy in sperm sexing. However, for the correct standardization of the technique, some laboratory methodologies are required. The present manuscript describes in detail a standardized equine sperm sex-sorting protocol using an absolute qPCR-based methodology. Furthermore, the results of absolute qPCR were implemented and validated by generating equine/bovine heterologous embryos by intracytoplasmic sperm injection (ICSI) of presumably sexed equine spermatozoa into bovine oocytes using a piezoelectric system (Piezo-ICSI). Our results indicated that equine sex-sorting spermatozoa had a 97% and 94% certainty for X and Y sperm, respectively, while presumptive female and male equine/bovine hybrid embryos, generated by Piezo-ICSI, had an accuracy of 92% with respect to the desired sex. Therefore, it is concluded that the presented methodology is a reliable, cost-effective, and relatively simple option for standardizing sex-sorting of equine spermatozoa. This is supported by the results of the correct sexing of Piezo-ICSI heterologous embryos generated with the sexed spermatozoa, validating the correct sexing and viability of these gametes.

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Ba0.92Ca0.08Ti0.95Zr0.05O3 (BCZT8-5) ceramic materials have been scarcely studied as lead-free piezo/ferroelectrics despite their enhanced Curie temperature (>100 °C) with respect to most studied BCZT compositions. In this work, homogeneous dense BCZT8-5 ceramics with grain size in the range of 20 µm, and optimum ferroelectric, dielectric, and electromechanical performance, were prepared by the mixed oxides route using moderate synthesis (1250 °C-2 h) and sintering (1400 °C-2 h) conditions. Thickness-poled thin disks and monomodal shear plate resonators were used for the determination of piezoelectric coefficients, coupling factors, elastic, and dielectric permittivity coefficients, including all losses, by iterative analysis of impedance curves at resonance. Furthermore, the thermal evolution of the piezoelectric characteristics at resonance was determined to assess the enhanced working range of the ceramics (≈100 °C). Ferroelectric hysteresis loops and strains vs. electric-field butterfly loops were also measured and showed soft behavior with Ec = 2 kV/cm, Pr = 12 µC/cm2 after a maximum applied field of 3 kV was used. The ceramics showed a high endurance of P-E cycles to electrical fatigue up to 107 cycles. Moreover, dielectric properties as a function of temperature were also accomplished and showed nearly normal ferroelectric behavior, characteristic of samples with low crystallographic disorder. Overall, these ceramics showed high sensitivity and higher stability than other currently studied BCZT compositions.

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Piezo1 channel is a sensor for shear-stress in the vasculature. Piezo1 activation induces vasodilation, and its deficiency contributes to vascular disorders, such as hypertension. In this study, we aimed to determine whether Piezo1 channel has a functional role in the dilation of pudendal arteries and corpus cavernosum (CC). For this, male Wistar rats were used, and the relaxation of the pudendal artery and CC was obtained using the Piezo1 activator, Yoda1, in the presence and absence of Dooku (Yoda1 antagonist), GsMTx4 (non-selective mechanosensory channel inhibitor) and L-NAME (nitric oxide synthase inhibitor). In the CC, Yoda1 was also tested in the presence of indomethacin (non-selective COX inhibitor) and tetraethylammonium (TEA, non-selective potassium channel inhibitor). The expression of Piezo1 was confirmed by Western blotting. Our data show that Piezo1 activation leads to the relaxation of the pudendal artery and CC as the chemical activator of Piezo1, Yoda1, relaxed the pudendal artery (47%) and CC (41%). This response was impaired by L-NAME and abolished by Dooku and GsMTx4 in the pudendal artery only. Indomethacin and TEA did not affect the relaxation induced by Yoda1 in the CC. Limited tools to explore this channel prevent further investigation of its underlying mechanisms of action. In conclusion, our data demonstrate that Piezo1 is expressed and induced the relaxation of the pudendal artery and CC. Further studies are necessary to determine its role in penile erection and if erectile dysfunction is associated with Piezo1 deficiency.

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Intracytoplasmic sperm injection (ICSI) is an assisted reproductive technique mainly used to overcome severe infertility problems associated with the male factor, but in cattle its efficiency is far from optimal. Artificial activation treatments combining ionomycin (Io) with 6-dimethylaminopurine after piezo-ICSI or anisomycin after conventional ICSI have recently increased the blastocyst rate obtained. Compounds to capacitate bovine spermatozoa, such as heparin and methyl-ß-cyclodextrin and compounds to destabilize sperm membranes such as NaOH, lysolecithin and Triton X-100, have been assessed, although they have failed to substantially improve post-ICSI embryonic development. Disulfide bond reducing agents, such as dithiothreitol (DTT), dithiobutylamine and reduced glutathione, have been assessed to decondense the hypercondensed head of bovine spermatozoa, the two latter being more efficient than DTT and less harmful. Although piezo-directed ICSI without external activation has generated high fertilization rates and modest rates of early embryo development, other studies have required exogenous activation to improve the results. This manuscript thoroughly reviews the different strategies used in bovine ICSI to improve its efficiency and proposes some alternative approaches, such as the use of extracellular vesicles (EVs) as 'biological methods of oocyte activation' or the incorporation of EVs in the in vitro maturation and/or culture medium as antioxidant defence agents to improve the competence of the ooplasm, as well as a preincubation of the spermatozoa in estrous oviductal fluid to induce physiological capacitation and acrosome reaction before ICSI, and the use of hyaluronate in the sperm immobilization medium.

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Bone presents different systemic functionalities as calcium phosphate reservoir, organ protection, among others. For that reason, the bone health conditions are essential to keep in equilibrium the metabolism of several body systems. Different technologies exist to diagnose bone conditions with invasive methods based on ionizing radiation. Therefore, there is a challenge to develop new ways to evaluate bone alterations in a noninvasive form. This study shows the assessment of a piezo-actuated device acting on a human tooth for the bio-monitoring of bone alterations. The bone diagnosis is performed by applying the electromechanical impedance technique (EMI), commonly used in structural health monitoring. For the experimental tests, five bone samples were prepared, and one was chosen as the monitoring. All samples were put in a decalcifying substance (TBD1 acid-base) at different times to emulate localized bone mineral alterations. Bone reductions were computed by using X-ray micro-computed tomography analyzing the morphometry. Electrical resistance measurements (piezo-device) were taken for the monitoring specimen meanwhile it was partially decalcified during 8520 seconds. In the frequency spectrum, several observation windows showed that the bone alterations gradually changed the electrical resistance signals which were quantified statistically. Results evidenced that the bone density changes are correlated with the electrical resistance measurements; these changes presented an exponential behavior as much as in the calculated index, and bone mineral reduction. The results demonstrated that bone alterations exhibit linear dependence with the computed statistical indexes. This result confirms that it is possible to observe the bone changes from the teeth as a future application.

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Bone is a dynamic biological tissue that acts as the primary rigid support of the body. Several systemic factors are responsible for pathologies that negatively affect its structural attributes. Although the bone is in continuous renewal by osteogenesis, metabolic diseases are the most common affectations that alter its natural equilibrium. Different techniques based on ionizing radiation are used for the bone diagnosis restrictively. However, if these are not used adequately, the application could present risks for human health. In this paper, it is proposed and explored a new technique to apply an early-stage diagnosis of bone variations. The technique evaluates bone structural conditions from the teeth (used as probes) by applying a structural health monitoring (SHM) methodology. An experimental procedure is described to identify the stiffness variations produced by mechanical drillings done in prepared bone samples. The identification is carried out applying the electromechanical impedance technique (EMI) through a piezo-actuated device in the frequency spectrum 5-20kHz. Three bone samples with incorporated teeth (three teeth, two teeth, and one tooth) were prepared to emulate a mandibular portion of alveolar bone-PDL (periodontal ligament)-tooth system. Piezo-device was attached to the crown of the tooth with an orthodontic bracket allowing the teeth to act as probes. The electrical resistance measurements were computed with an electrical decoupling approach that improved the detection of the drillings; it was due to the increment of the sensitivity of the signals. The results showed that the bone mass reduction is correlated with statistical indices obtained in specific frequency intervals of the electrical resistance. This work suggests the possibility of a future application addressed to a bone diagnosis in a non-invasive way.

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La xerocitosis hereditaria es un desorden poco frecuente causado por defectos en la permeabilidad eritrocitaria, que se caracteriza por anemia hemolítica de gravedad variable y sobrecarga de hierro. El diagnóstico suele ser tardío y confundirse con otras anemias hemolíticas, lo que puede llevar a indicaciones de procedimientos, como la esplenectomía, contraindicados en estos pacientes. Se reportan las características clínicas, hematológicas y moleculares de dos pacientes pediátricos no relacionados con diagnóstico de xerocitosis hereditaria. Ambos presentaban eritrocitos deshidratados con alta concentración de hemoglobina corpuscular media, frotis no patognomónico, marcadores de hemólisis y una curva de fragilidad osmótica resistente. El diagnóstico se confirmó por la secuenciación del gen PIEZO.Se resalta la importancia de reconocer la causa de la anemia hemolítica para dar un enfoque terapéutico preciso y dar adecuado consejo genético

Hereditary xerocytosis is a rare disorder caused by defects of red blood cell permeability that are characterized by hemolytic anemia of variable degree and iron overload. Diagnosis is usually late and confused with other hemolytic anemias, which can lead to procedural indications, such as splenectomy, contraindicated in these patients. We report the clinical, haematological, and molecular characteristics of two patients from two unrelated families affected by hereditary xerocytosis. Both patients had dehydrated erythrocytes with a high concentration of mean corpuscular hemoglobin, non-pathognomonic smears, markers of hemolysis and a resistant osmotic fragility curve. The diagnosis was confirmed by the sequencing of the PIEZO gene. We emphasize the importance of recognizing the cause of hemolytic anemia to give an accurate therapeutic approach and give adequate genetic counseling.

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Hereditary xerocytosis is a rare disorder caused by defects of red blood cell permeability that are characterized by hemolytic anemia of variable degree and iron overload. Diagnosis is usually late and confused with other hemolytic anemias, which can lead to procedural indications, such as splenectomy, contraindicated in these patients. We report the clinical, haematological, and molecular characteristics of two patients from two unrelated families affected by hereditary xerocytosis. Both patients had dehydrated erythrocytes with a high concentration of mean corpuscular hemoglobin, non-pathognomonic smears, markers of hemolysis and a resistant osmotic fragility curve. The diagnosis was confirmed by the sequencing of the PIEZO gene. We emphasize the importance of recognizing the cause of hemolytic anemia to give an accurate therapeutic approach and give adequate genetic counseling.

La xerocitosis hereditaria es un desorden poco frecuente causado por defectos en la permeabilidad eritrocitaria, que se caracteriza por anemia hemolítica de gravedad variable y sobrecarga de hierro. El diagnóstico suele ser tardío y confundirse con otras anemias hemolíticas, lo que puede llevar a indicaciones de procedimientos, como la esplenectomía, contraindicados en estos pacientes. Se reportan las características clínicas, hematológicas y moleculares de dos pacientes pediátricos no relacionados con diagnóstico de xerocitosis hereditaria. Ambos presentaban eritrocitos deshidratados con alta concentración de hemoglobina corpuscular media, frotis no patognomónico, marcadores de hemólisis y una curva de fragilidad osmótica resistente. El diagnóstico se confirmó por la secuenciación del gen PIEZO. Se resalta la importancia de reconocer la causa de la anemia hemolítica para dar un enfoque terapéutico preciso y dar adecuado consejo genético.

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Objetivo: Presentar una técnica quirúrgica de disyunción con bisturí piezoeléctrico y expansión de rebordes delgados en maxilar inferior que permita la colocación de implantes en la posición tridimensional correcta en el mismo acto quirúrgico. Casos clínicos: Se presenta la resolución de dos casos clínicos de pacientes que acudieron a la Cátedra de Odontología Integral Adultos de la Facultad de Odontología de la Universidad de Buenos Aires. Ambos requerían la colocación de implantes en sectores posteroinferiores. Las imágenes tomográficas mostraban adecuada altura del reborde alveolar pero deficiente espesor para la colocación de implantes en la posición tridimensional correcta. Se decidió realizar una técnica de disyunción horizontal del reborde alveolar con bisturí piezoeléctrico, expansión del reborde y colocación de implantes e injerto óseo particulado de forma simultánea. Luego de 3 meses, se efectuó la segunda cirugía para iniciar la rehabilitación protésica. Conclusión: La técnica de disyunción horizontal del reborde alveolar mediante el uso del bisturí piezoeléctrico permitió ubicar al implante en la posición tridimensional correcta dentro del tejido óseo nativo sin la necesidad de realizar regeneraciones complejas en rebordes alveolares delgados (AU)

Aim: Present the horizontal split crest technique with a piezoelectric scalpel and the immediate implant placement in the correct tridimensional position, in thin mandibular alveolar ridges. Cases report: The surgical resolutions of 2 clinical cases of patients who attended the Adult Integral Dentistry Chair of the Faculty of Dentistry of the UBA, are presented. Both patients required implant placement in posterior madibular residual ridge. The tomographic images showed adequate height of the alveolar ridge but poor thickness for implants placement in a correct three-dimensional position. It was decided to perform a horizontal split crest technique of the alveolar ridge with piezoelectric scalpel, ridge expansion, and immediate implant placement with xenograft. After 3 months, the second surgery was performed to start with the prosthetic rehabilitation. Conclusion: The horizontal split crest technique using a piezoelectric scalpel, allowed immediate implant placement in the correct tridimensional position within native bone tissue, avoiding a guided bone regeneration technique, in these cases with thin alveolar ridges (AU)

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This study exposes the assessment of a piezo-actuated sensor for monitoring elastic variations (change in Young's modulus) of a host structure in which it is attached. The host structure is monitored through a coupling interface connected to the piezo-actuated device. Two coupling interfaces were considered (an aluminum cone and a human tooth) for the experimental tests. Three different materials (aluminum, bronze and steel) were prepared to emulate the elastic changes in the support, keeping the geometry as a fixed parameter. The piezo device was characterized from velocity frequency response functions in pursuance to understand how vibration modes stimulate the electrical resistance through electrical resonance peaks of the sensor. An impedance-based analysis (1⁻20 kHz) was performed to correlate elastic variations with indexes based on root mean square deviation (RMSD) for two observation windows (9.3 to 9.7 kHz and 11.1 to 11.5 kHz). Results show that imposed elastic variations were detected and quantified with the electrical resistance measurements. Moreover, it was demonstrated that the sensitivity of the device was influenced by the type of coupling interface since the cone was more sensitive than the tooth in both observation windows. As a final consideration, results suggest that bio-structures (fruits and bone, among others) could be studied since these can modify naturally its elastic properties.

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Enterochromaffin (EC) cells synthesize 95% of the body 5-HT and release 5-HT in response to mechanical or chemical stimulation. EC cell 5-HT has physiological effects on gut motility, secretion and visceral sensation. Abnormal regulation of 5-HT occurs in gastrointestinal disorders and Inflammatory Bowel Diseases (IBD) where 5-HT may represent a key player in the pathogenesis of intestinal inflammation. The focus of this review is on mechanism(s) involved in EC cell "mechanosensation" and critical gaps in our knowledge for future research. Much of our knowledge and concepts are from a human BON cell model of EC, although more recent work has included other cell lines, native EC cells from mouse and human and intact mucosa. EC cells are "mechanosensors" that respond to physical forces generated during peristaltic activity by translating the mechanical stimulus (MS) into an intracellular biochemical response leading to 5-HT and ATP release. The emerging picture of mechanosensation includes Piezo 2 channels, caveolin-rich microdomains, and tight regulation of 5-HT release by purines. The "purinergic hypothesis" is that MS releases purines to act in an autocrine/paracrine manner to activate excitatory (P2Y1, P2Y4, P2Y6, and A2A/A2B) or inhibitory (P2Y12, A1, and A3) receptors to regulate 5-HT release. MS activates a P2Y1/Gαq/PLC/IP3-IP3R/SERCA Ca2+signaling pathway, an A2A/A2B-Gs/AC/cAMP-PKA signaling pathway, an ATP-gated P2X3 channel, and an inhibitory P2Y12-Gi/o/AC-cAMP pathway. In human IBD, P2X3 is down regulated and A2B is up regulated in EC cells, but the pathophysiological consequences of abnormal mechanosensory or purinergic 5-HT signaling remain unknown. EC cell mechanosensation remains poorly understood.

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Tooth loss leads to a decrease in alveolar bone volume, and consequently to the need for guided bone regeneration (GBR) techniques to restore bone anatomy, and the adequate choice of therapy. Fascia lata membrane (FLM) has been used in surgical procedures in neurology, orthopedics, otorhinolaryngology, cardiology, vascular surgery, gynecology, and dentistry for guided tissue regeneration. The aim of the present preliminary study was to evaluate bone tissue response in rat calvarial bone defects covered with human fascia lata membrane (FLM). Eight Wistar rats, 230g body weight, were subjected to bone surgery to create a 5x5mm long/ 1mm deep calvarial bone defect on either side of the median suture, using a piezoelectric scalpel and irrigation. The animals were treated according to the following protocol: Group I (GI): placement of a single layer of FLM (Biotar, Rosario, Prov. de Santa Fe, Argentina) to cover the defects; Group II (GII): double layer of FLM to cover the defects; Group III: no membrane; Group IV: control. All the animals were euthanized 60 days post-surgery; the heads were resected, radiographed, decalcified, and processed for embedding in paraffin and Hematoxylin-Eosin and Masson's trichrome staining. All bone defects covered with a single or double layer of FLM showed adequate osteogenesis, and none exhibited an inflammatory response. Groups III and IV Control showed scant osteogenesis and no alterations in soft tissues. The results obtained with this experimental model show biocompatibility of FML with the surrounding tissues at the studied time points. No alterations were observed in osteocytic lacunae or osteocytes in the bone after osteotomy using a piezoelectric scalpel. Further studies need to be conducted to assess bone tissue response to FLM in combination with bone substitutes.

La perdida de piezas dentarias conlleva la disminucion volumetrica del hueso alveolar y la necesidad de recurrir a tecnicas de regeneracion osea guiada (ROG) para restablecer las condiciones anatomicas y aplicar las terapeuticas adecuadas. La membrana de fascia lata (MFL) ha sido utilizada en intervenciones quirurgicas del area neurologica, ortopedica, otorrinolaringologica, cardiologica, vascular, ginecologica y odontologica para regeneracion tisular guiada. El objetivo de este trabajo preliminar fue evaluar la respuesta tisular de defectos oseos en calota de rata recubiertos con MFL. Se utilizaron 8 ratas Wistar de 230 gr de peso, a las que se les realizo en la calota 2 defectos oseos de 5 x 5 mm de lado por 1 mm de profundidad, con bisturi piezoelectrico e irrigacion, a ambos lados de la linea media, segun tecnica estandarizada. Se realizo el siguiente protocolo: Grupo I (G I): colocacion de una sola capa de MFL (Biotar, Rosario, Prov. de Santa Fe, Argentina) para cubrir el defecto; Grupo II (G II): colocacion de MFL en doble capa para cubrir el defecto; Grupo III (G III): sin membrana; Grupo IV (G IV): control. Se les provoco la eutanasia a los 60 dias. Las calotas fueron resecadas, radiografiadas y procesadas, previa descalcifica - cion, para su inclusion en parafina y coloracion con Hematoxilina-Eosina y Tricromico de Masson. En todos los defectos oseos recubiertos con MFL simple o doble se evidencio una adecuada osteogenesis y ausencia de respuesta inflamatoria y macrofagos. El G III y el G Sham evidenciaron escasa osteogenesis y no mostraron alteraciones en el tejido blando. La MFL en el modelo experimental utilizado evidencio una respuesta compatible con el tejido circundante en los periodos estudiados. El tejido oseo remanente a la osteotomia con bisturi piezoelectrico presento las lagunas osteociticas ocupadas con osteocitos y sin alteraciones. En estudios futuros se evaluara la respuesta tisular con MFL y utilizando un sustituto oseo.

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OBJETIVE: This preliminary study aimed to evaluate clinically and microbiologically the treatment of patients with light to moderate periodontal disease by using an ultrasonic device. MATERIAL AND METHODS: Sixteen adults with moderate periodontitis were studied. A Real-time PCR protocol was optimised using specific primers for the three microorganisms. Clinical and microbiological testing was performed prior and following treatment. RESULTS: Despite clinical improvement, bacteria quantification didn’t change. All the patients were positive for P. gingivalis and P. intermedia and nine for A. actinomycetemcomitans. CONCLUSION: VectorTM-system treatment showed clinical improvement. A Real-time PCR protocol is now available for periodontal diagnostics and monitorization. However, further studies with larger populations are indicated.

OBJETIVOS: Este estudo preliminar teve a finalidade de avaliar clinicamente microbiologicamente o tratamento de pacientes portadores de periodontite leve a moderada, utilizando-se um novo aparelho piezo-elétrico disponível no mercado (VectorTM system). MATERIAL E MÉTODO: Dezesseis pacientes adultos, portadores de periodontite leve a moderada, foram submetidos ao tratamento. Utilizou-se um protocolo de PCR em tempo real utilizando primers específicos para três microrganismos. Realizaram-se avaliação clínica e um estudo microbiológico simultâneo antes e após os tratamentos. RESULTADOS: A avaliação clínica foi positiva, embora não tendo ocorrido alterações na quantidade de bactérias. Todos os pacientes apresentaram amplificação específica para P. intermedia e P. gingivalis e nove pacientes para A. Actinomycetemcomitans. CONCLUSÃO: Considerando-se os resultados deste estudo preliminar, tratamento com o aparelho testado mostrou eficácia clínica. O protocolo utilizado neste estudo está agora disponível para diagnóstico periodontal e monitoração de resultados de tratamento. Entretanto, indica-se estudos clínicos e microbiológicos mais aprofundados, com amostras maiores, para conclusões mais consistentes.

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