Publications by authors named "Alexander Morrell"

Komodo dragons (Varanus komodoensis) are the largest extant predatory lizards and their ziphodont (serrated, curved and blade-shaped) teeth make them valuable analogues for studying tooth structure, function and comparing with extinct ziphodont taxa, such as theropod dinosaurs. Like other ziphodont reptiles, V. komodoensis teeth possess only a thin coating of enamel that is nevertheless able to cope with the demands of their puncture-pull feeding.

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Periodontal disease is a significant burden for oral health, causing progressive and irreversible damage to the support structure of the tooth. This complex structure, the periodontium, is composed of interconnected soft and mineralised tissues, posing a challenge for regenerative approaches. Materials combining silicon and lithium are widely studied in periodontal regeneration, as they stimulate bone repair via silicic acid release while providing regenerative stimuli through lithium activation of the Wnt/β-catenin pathway.

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Migration of T cells is essential for their ability to mount immune responses. Chemokine-induced T cell migration requires WNK1, a kinase that regulates ion influx into the cell. However, it is not known why ion entry is necessary for T cell movement.

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Introduction: Inguinoscrotal hernias (ISH) pose a challenge to surgeons with consistently higher rates of postoperative complications and recurrence rates. The aim of this study is to report our initial experience and early results with a new technique for inguinoscrotal hernia repair.

Methods: A review of a prospectively maintained multi-center database was conducted in patients who underwent minimally invasive repair using the "primary abandon-of-the-sac" (PAS) technique for inguinoscrotal hernias from March 2021 to July 2022.

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Zinc (Zn) has antioxidant, anti-inflammatory and anti-proliferative actions, with Zn dysregulation associated with coronary ischemia/reperfusion injury and smooth muscle cell dysfunction. As the majority of studies concerning Zn have been conducted under non-physiological hyperoxic conditions, we compare the effects of Zn chelation or supplementation on total intracellular Zn content, antioxidant NRF2 targeted gene transcription and hypoxia/reoxygenation-induced reactive oxygen species generation in human coronary artery smooth muscle cells (HCASMC) pre-adapted to hyperoxia (18 kPa O) or normoxia (5 kPa O). Expression of the smooth muscle marker SM22-α was unaffected by lowering pericellular O, whereas calponin-1 was significantly upregulated in cells under 5 kPa O, indicating a more physiological contractile phenotype under 5 kPa O.

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Exposure to exogenous particles is of increasing concern to human health. Characterizing the concentrations, chemical species, distribution, and involvement of the stimulus with the tissue microanatomy is essential in understanding the associated biological response. However, no single imaging technique can interrogate all these features at once, which confounds and limits correlative analyses.

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Zinc is an important component of cellular antioxidant defenses and dysregulation of zinc homeostasis is a risk factor for coronary heart disease and ischemia/reperfusion injury. Intracellular homeostasis of metals, such as zinc, iron and calcium are interrelated with cellular responses to oxidative stress. Most cells experience significantly lower oxygen levels in vivo (2-10 kPa O) compared to standard in vitro cell culture (18kPa O).

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Objective: minimally invasive bariatric surgery is clearly superior over open procedures including better early outcomes. Different surgical approaches are used to treat the severely obese, having Roux-en-Y gastric bypass (RYGB) being a highly frequent procedure. Robotic surgery overcomes some laparoscopic limitations adding ergonomics, articulating instruments and a three-dimensional high definition camera.

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The World Health Organisation has called for a 40% increase in personal protective equipment manufacturing worldwide, recognising that frontline workers need effective protection during the COVID-19 pandemic. Current devices suffer from high fit-failure rates leaving significant proportions of users exposed to risk of viral infection. Driven by non-contact, portable, and widely available 3D scanning technologies, a workflow is presented whereby a user's face is rapidly categorised using relevant facial parameters.

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Background: laparoscopy surgery has many proven clinical advantages over conventional surgery and more recently, robotic surgery has been the emerging platform in the minimally invasive era. In the colorectal field, although overcoming limitations of standard laparoscopy, robotic surgery still faces challenging situations even by the most experienced colorectal surgeons. This study reports essentials technical aspects and comparison between Da Vincis Si and Xi platforms aiming to master and maximize efficiency whenever performing robotic colorectal surgery.

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Succinate dehydrogenase is a key enzyme in the tricarboxylic acid cycle and the electron transport chain. All four subunits of succinate dehydrogenase are tumor suppressor genes predisposing to paraganglioma, but only mutations in the SDHB subunit are associated with increased risk of metastasis. Here we generated an knockout chromaffin cell line and compared it with deficient cells.

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Containing the global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been an unprecedented challenge due to high horizontal transmissivity and asymptomatic carriage rates. Lateral flow device (LFD) immunoassays were introduced in late 2020 to detect SARS-CoV-2 infection in asymptomatic or presymptomatic individuals rapidly. While LFD technologies have been used for over 60 years, their widespread use as a public health tool during a pandemic is unprecedented.

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Background: Fluorescent imaging with indocyanine green is an emerging technology whose benefits are put in perspective.

Objective: This article reports essential principles and approaches of intraoperative fluorescence in general surgery bringing familiarity to its practical usage. Our group describes possible pitfalls and provides tips and tricks for training surgeons making their attempts easier and reproducible during practice.

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Introduction: currently, there are several clinical applications for robot-assisted surgery and in the hernia scenario, robot-assisted surgery seems to have the ability to overcome laparoscopic ventral hernias repairs limitations, facilitating dissection, defect closure, and mesh positioning. Exponentially grown in numbers of robotic approaches have been seen and even more complex and initially not suitable cases have recently become eligible for it. An appropriate tension-free reestablishment of the linea alba is still a major concern in hernia surgery and even with the robotic platform, dissecting and suturing in anterior abdominal wall may be challenging.

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Objectives: minimally invasive inguinal hernia repair has proven advantages over open procedures including less pain and earlier return to normal activity. Robotic surgery adds ergonomics, a three-dimensional high definition camera and articulating instruments overcoming some laparoscopic limitations. We aimed to report the outcomes of the early experience of over 97 robotic inguinal hernia repairs performed by a referred surgical group in Brazil.

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The term "robot" was concepted in the beginning of last century, coming originally from the Czech word "robota", meaning "labor". More recently, computer assistance and robotics based in the telepresence and virtual reality concept have been applied to surgical procedures. The application of robots in surgery dates approximately 35 years, experiencing significant growth in the last two decades fueled by the advent of advanced technologies.

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Background: Laparoscopic best approach of repairing inguinoscrotal hernias are still debatable. Incorrect handling of the distal sac can possibly result in damage to cord structures and negative postoperative outcomes as ischemic orquitis or inguinal neuralgia.

Aim: To describe a new technique for a minimally invasive approach to inguinoscrotal hernias and to analyze the preliminary results of patients undergoing the procedure.

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Endometriosis in the vermiform appendix is a rare condition that affects women of childbearing age. The clinical picture can simulate inflammatory acute abdominal pain, especially acute appendicitis. Laboratory and imaging tests may assist in the diagnosis but are not conclusive.

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Objectives: described by Dr. Jorge Daes, principles of the enhanced view totally extraperitoneal (eTEP) has been widely used in the armamentarium of ventral hernia repair recently. Robotic assisted eTEP technique feasibility has been proved, however, a complete understanding of retromuscular abdominal wall planes and its landmarks still uncertain in a majority of general surgeons.

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Degradation of the implant surface and particle release/formation as an inflammation catalyst mechanism is an emerging concept in dental medicine that may help explain the pathogenesis of peri-implantitis. The aim of the present study was a synchrotron-based characterization of micro- and nanosized implant-related particles in inflamed human tissues around titanium and ceramic dental implants that exhibited signs of peri-implantitis. Size, distribution, and chemical speciation of the exogenous micro- and nanosized particle content were evaluated using synchrotron μ-X-ray fluorescence spectroscopy (XRF), nano-XRF, and μ-X-ray absorption near-edge structure (XANES).

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The coronavirus infection, also known as SARS-COV2, has proven to be potentially fatal, representing a major global health problem. Its spread after its origin in the city of Wuhan, China has resulted in a pandemic with the collapse of the health system in several countries, some with enormous social impact and expressive number of deaths as seen in Italy and Spain. Extreme intra and extra-hospital measures have been implemented to decrease the transmission and dissemination of the COVID-19.

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Objective: The structure of the polymer phase of dental resin-based-composites is highly sensitive to photo-polymerisation variables. The objective of this study was to understand how different polymer structures, generated with different photo-polymerisation protocols, respond to thermal perturbation.

Methods: Experimental resins were prepared from a series of Bis-GMA/TEGDMA blends (40/60, 50/50 and 60/40 wt.

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Inguinal hernias are a frequent problem and their repair is the most commonly performed procedure by general surgeons. In the last years, new principles, products and techniques have changed the routine of surgeons, who need to recycle knowledge and perfect new skills. In addition, old concepts regarding surgical indication and risk of complications have been reevaluated.

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Biological exposures to micro- and nano-scale exogenous metal particles generated as a consequence of in-service degradation of orthopaedic prosthetics can result in severe adverse tissues reactions. However, individual reactions are highly variable and are not easily predicted, due to in part a lack of understanding of the speciation of the metal-stimuli which dictates cellular interactions and toxicity. Investigating the chemistry of implant derived metallic particles in biological tissue samples is complicated by small feature sizes, low concentrations and often a heterogeneous speciation and distribution.

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Background: Diastasis of the rectus abdominis muscles (DMRA) is frequent and may be associated with abdominal wall hernias. For patients with redudant skin, dermolipectomy and plication of the diastasis is the most commonly used procedure. However, there is a significant group of patients who do not require skin resection or do not want large incisions.

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