Rheology of different hydrocolloids-rice starch blends. Effect of successive heating-cooling cycles

10 pages, 3 figures, 5 tables.-- Available online 25 November 2010.Hydrocolloids are frequently used for modifying starch functionality. In the present study the possible interaction of three different hydrocolloids – guar gum, hydroxypropylmethylcellulose (HPMC) and xanthan gum – with rice starch was explored by determining the pasting, viscoelastic and swelling properties of the rice starch–hydrocolloids mixtures. The impact of successive heating–cooling cycles on the pasting, viscoelasticity and swelling was also determined. Hydrocolloids tested in the range 0.2–0.8% (w/w) significantly modified the pasting, viscoelastic and swelling properties of rice starch–hydrocolloid pastes (8%, w/w) and the extent of the effect was dependent on hydrocolloid concentration. Guar and xanthan gum mixtures with rice starch had the greatest effect on the pasting properties, whereas HPMC mixtures only changed the viscosity during cooling. The starch–hydrocolloids pastes formed weaker gels compared to those of the starch alone. Rheological results suggested the formation of composite network structures with high frequency dependence. Successive multiple-heating cycles allowed the gel to rearrange resulting in altered gel viscoelasticity and release of water soluble compounds that favour phase separation at the highest hydrocolloid level tested.Financial support from University of California-Davis, Ministry of Education and Science, Spanish Research National Council (CSIC) and Spanish Ministerio de Ciencia e Innovación (Project AGL2008-00092/ALI) is gratefully acknowledged. Dr. Rosell thanks the Spanish Ministry of Education and Science for her grant.Peer reviewe

Chronic Activation of Hepatic Nrf2 Has No Major Effect on Fatty Acid and Glucose Metabolism in Adult Mice

The transcription factor NF-E2-related factor 2 (Nrf2) induces cytoprotective genes, but has also been linked to the regulation of hepatic energy metabolism. In order to assess the pharmacological potential of hepatic Nrf2 activation in metabolic disease, Nrf2 was activated over 7 weeks in mice on Western diet using two different siRNAs against kelch-like ECH-associated protein 1 (Keap1), the inhibitory protein of Nrf2. Whole genome expression analysis followed by pathway analysis demonstrated successful knock-down of Keap1 expression and induction of Nrf2-dependent genes involved in anti- oxidative stress defense and biotransformation, proving the activation of Nrf2 by the siRNAs against Keap1. Neither the expression of fatty acid- nor carbohydrate-handling proteins was regulated by Keap1 knock-down. Metabolic profiling of the animals did also not show effects on plasma and hepatic lipids, energy expenditure or glucose tolerance. The data indicate that hepatic Keap1/Nrf2 is not a major regulator of glucose or lipid metabolism in mice

A Review of Full-endoscopic Interlaminar Discectomy for Lumbar Disc Disease: A Historical and Technical Overview

Lumbar disc disease is an age or trauma-related disc injury with the clinical symptoms such as lower back pain or sciatica. Surgical treatment is the reliable and effective solution only if the symptoms grow progressively worse and conservative treatments fail. The purpose of spinal surgery is to remove the real pain generator and maintain physiological spinal alignment. Traditionally, patients after discectomy tend to experience the risk of postoperative intervertebral disc degeneration with intractable low back pain. Therefore, the minimally invasive techniques have rapidly developed in the past decades and brought revolutionary progress on techniques modification. Herein, we report the historical overview of the interlaminar full-endoscopic lumbar discectomy and technical evolution based on the review of literature

Worldwide research productivity in the field of full-endoscopic spine surgery: a bibliometric study.

PURPOSE(#br)To investigate the quantity and quality of articles in the field of full-endoscopic spine surgery (FESS) from different countries and assess characteristics of worldwide research productivity.(#br)METHODS(#br)Articles published from 1997 to July 23, 2018, were screened using the Web of Science database. All studies were assessed for the following parameters: the number of total publications, h-index, contribution of countries, authors, journals, and institutions.(#br)RESULTS(#br)A total of 408 articles were identified between 1997 and 2018. Between 1997 and 2017, the number of published articles tended to increase by 41 times. The largest number of articles was from China (30.15%), followed by South Korea (28.68%), the USA (13.97%), Germany (9.31%), and Japan (4.90%). The highest h-index was found for articles from South Korea (23), followed by the USA (18), Germany (16), China (11), and Japan (7). The highest number of articles was published in World Neurosurgery (12.50%), followed by Pain Physician (10.29%), Spine (6.62%), European Spine Journal (4.66%), and Journal of Neurosurgery: Spine (4.17%). Wooridul Spine Hospital published the largest number of articles (10.29%), followed by Tongji University (5.88%), University of Witten/Herdecke (5.39%), Brown University (5.15%), and Third Military Medical University (3.43%).(#br)CONCLUSIONS(#br)The number of articles published in the field of FESS has increased rapidly in the past 20 years. In terms of quantity, China is the most contributive country based on the number of publications. High-quality papers as measured by h-index and the large quantity is from South Korea (second only to China). These slides can be retrieved under Electronic Supplementary Material

SARS-CoV-2 particles promote airway epithelial differentiation and ciliation

Introduction: The Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), which caused the coronavirus disease 2019 (COVID-19) pandemic, enters the human body via the epithelial cells of the airway tract. To trap and eject pathogens, the airway epithelium is composed of ciliated and secretory cells that produce mucus which is expelled through a process called mucociliary clearance.Methods: This study examines the early stages of contact between SARS-CoV-2 particles and the respiratory epithelium, utilizing 3D airway tri-culture models exposed to ultraviolet light-irradiated virus particles. These cultures are composed of human endothelial cells and human tracheal mesenchymal cells in a fibrin hydrogel matrix covered by mucociliated human tracheal epithelial cells.Results: We found that SARS-CoV-2 particles trigger a significant increase in ciliation on the epithelial surface instructed through a differentiation of club cells and basal stem cells. The contact with SARS-CoV-2 particles also provoked a loss of cell-cell tight junctions and impaired the barrier integrity. Further immunofluorescence analyses revealed an increase in FOXJ1 expression and PAK1/2 phosphorylation associated with particle-induced ciliation.Discussion: An understanding of epithelial responses to virus particles may be instrumental to prevent or treat respiratory infectious diseases such as COVID-19

Сучасний стан ендоскопічної хірургії міжхребцевого диска: огляд контрольованих досліджень порівняння ендоскопічних та стандартних операцій для лікування гриж міжхребцевих дисків

Background: Endoscopic spinal surgery is increasingly popular because it minimizes access trauma and hastens recovery from the intervention. Objective: To assess the clinical outcomes and complication rates of full-endoscopic disc surgery compared to the microsurgical standard procedures. Methods: A PubMed and Embase search was performed, considering entries up to January 2013. Only 5 controlled trials of 504 articles could finally be considered for evaluation. Results: Overall, the endoscopic techniques had shorter operating times, less blood loss, less operative site pain, and faster postoperative rehabilitation / shorter hospital stay / faster return to work than the microsurgical techniques. All 5 studies had fewer complications with the endoscopic technique. Conclusions: The studies show that full-endoscopic disc surgery can achieve the same clinical results in symptomatic cervical and lumbar disc herniations as the microsurgical standard techniques.Предпосылки: популярность эндоскопической хирургии позвоночника возрастает, так как она минимизирует травматичность доступа и ускоряет выздоровление после вмешательства. Цель: оценить клинические результаты и частоту осложнений после эндоскопических операций на межпозвонковых дисках по сравнению с микрохирургическими стандартными операциями. Методы: был проведен информационный поиск с помощью электронно-поисковых систем PubMed и Embase с учетом поступлений до января 2013 г. Только 5 контролированных исследований из 504 статей были в конечном итоге отобраны для изучения. Результаты: в целом, эндоскопические операции характеризовались более коротким временем вмешательства, меньшей кровопотерей, меньшей интенсивностью боли в области операционной раны и более быстрым восстановлением / менее продолжительным пребыванием в больнице / более быстрым возвращением к труду, чем после микрохирургических операций. Во всех 5 работах было отмечено меньшее количество осложнений в результате эндоскопических операций. Заключение: результаты исследования показывают, что полностью эндоскопические операции на межпозвонковых дисках могут обеспечить такие же клинические результаты при симптоматических грыжах в шейном и поясничном отделах позвоночника, как и микрохирургические стандартные операции.Передумови: популярність ендоскопічної хірургії хребта зростає, тому що вона мінімізує травматичність доступу і прискорює одужання після втручання. Мета: оцінити клінічні результати і частоту ускладнень після ендоскопічних операцій на міжхребцевих дисках порівняно з мікрохірургічними стандартними операціями. Методи: проведено інформаційний пошук за допомогою електронно-пошукових систем PubMed и Embase з урахуванням надходжень до січня 2013 р. Лише 5 контрольованих досліджень з 504 статей були в кінцевому підсумку відібрані для вивчення. Результати: загалом, ендоскопічні операції характеризувалися коротшим часом втручання, меншою крововтратою, меншою інтенсивністю болю в ділянці операційної рани і швидкішим відновленням / менш тривалим перебуванням у лікарні / швидкішим поверненням до праці, ніж після мікрохірургічних операцій. У всіх 5 роботах було відзначено меншу кількість ускладнень внаслідок ендоскопічних операцій. Висновок: результати дослідження показують, що повністю ендоскопічні операції на міжхребцевих дисках можуть забезпечити такі самі клінічні результати у випадку симптоматичних гриж в шийному та поперековому відділах хребта, як і мікрохірургічні стандартні операції

Керівництво з черезшкірної ендоскопічної хірургії хребта

Randomized controlled trials have demonstrated equal effectiveness of the endoscopic procedures compared to the microsurgical reference procedures in cervical as well as in lumbar applications. Some of these studies also showed lower complication rates with endoscopy and none had higher complication rates with endoscopy. In these trials, spinal endoscopy generated less postoperative pain and faster rehabilitation than the microsurgical procedures. However, all these trials with one exception were performed by the same team of highly experienced endoscopic spinal surgeons. It is conceivable, that surgeons with less experience may not necessarily be able to achieve the same results. RCTs from other groups will have to prove or disprove this assumption. Sofar, no long-lasting advantages of endoscopic spine surgery over the microsurgical technique have been demonstrated. There is some experimental evidence that the effects of reduced access trauma can be measured, but interestingly, there seems to be no advantage of using a microtubular retractor system over standard microsuraical techniaue and instruments.Рандомизированные контролируемые исследования показали одинаковую эффективность эндоскопических и микрохирургических вмешательств на шейном и поясничном отделах позвоночника. Некоторые из этих исследований показали снижение количества осложнений после эндоскопических операций, но ни одно — о его повышении. Согласно полученным результатам, после эндоскопических операций на позвоночнике отмечена меньшая интенсивность послеоперационной боли и более быстрая реабилитация, чем после микрохирургии. Однако все исследования за исключением одного проведены одной и той же группой высокопрофессиональных хирургов. Поэтому возможно, что менее подготовленные специалисты не получат аналогичные результаты. Для подтверждения или опровержения этого предположения необходимы другие исследования. Пока никаких преимуществ эндоскопической хирургии перед микрохирургической техникой не продемонстрировано. Существует ряд экспериментальных доказательств возможной объективной оценки эффекта снижения травматичности доступа. Но предположительно нет преимуществ применения микротубулярной ретракторной системы перед стандартной микрохирургической техникой и инструментарием.Рандомізовані контрольовані дослідження показали однакову ефективність ендоскопічних та мікрохірургічних втручань на шийному та поперековому відділах хребта. Деякі з цих досліджень виявили зниження кількості ускладнень після ендоскопічних операцій, але жодне — його підвищення. Згідно з отриманими результатами після ендоскопічних операцій на хребті відзначена менша інтенсивність післяопераційного болю і швидша реабілітація, ніж після мікрохірургії. Проте всі дослідження, за винятком одного, проведені тією самою групою високопрофесійних хірургів. Тому можливо, що менш підготовлені фахівці не отримають аналогічні результати. Для підтвердження або спростування цього припущення необхідні інші дослідження. Поки ніяких переваг ендоскопічної хірургії перед мікрохірургічної технікою не продемонстровано. Існує низка експериментальних доказів можливої об’єктивної оцінки ефекту зниження травматичності доступу. Але імовірно немає переваг застосування мікротубулярної ретракторної системи перед стандартною мікрохірургічною технікою та інструментарієм

Navigation of Pedicle Screws in the Thoracic Spine with a New Electromagnetic Navigation System: A Human Cadaver Study

Introduction. Posterior stabilization of the spine is a standard procedure in spinal surgery. In addition to the standard techniques, several new techniques have been developed. The objective of this cadaveric study was to examine the accuracy of a new electromagnetic navigation system for instrumentation of pedicle screws in the spine. Material and Method. Forty-eight pedicle screws were inserted in the thoracic spine of human cadavers using EMF navigation and instruments developed especially for electromagnetic navigation. The screw position was assessed postoperatively by a CT scan. Results. The screws were classified into 3 groups: grade 1 = ideal position; grade 2 = cortical penetration <2 mm; grade 3 = cortical penetration ≥2 mm. The initial evaluation of the system showed satisfied positioning for the thoracic spine; 37 of 48 screws (77.1%, 95% confidence interval [62.7%, 88%]) were classified as group 1 or 2. Discussion. The screw placement was satisfactory. The initial results show that there is room for improvement with some changes needed. The ease of use and short setup times should be pointed out. Instrumentation is achieved without restricting the operator’s mobility during navigation. Conclusion. The results indicate a good placement technique for pedicle screws. Big advantages are the easy handling of the system

A New Electromagnetic Navigation System for Pedicle Screws Placement: A Human Cadaver Study at the Lumbar Spine.

Technical developments for improving the safety and accuracy of pedicle screw placement play an increasingly important role in spine surgery. In addition to the standard techniques of free-hand placement and fluoroscopic navigation, the rate of complications is reduced by 3D fluoroscopy, cone-beam CT, intraoperative CT/MRI, and various other navigation techniques. Another important aspect that should be emphasized is the reduction of intraoperative radiation exposure for personnel and patient. The aim of this study was to investigate the accuracy of a new navigation system for the spine based on an electromagnetic field.Twenty pedicle screws were placed in the lumbar spine of human cadavers using EMF navigation. Navigation was based on data from a preoperative thin-slice CT scan. The cadavers were positioned on a special field generator and the system was matched using a patient tracker on the spinous process. Navigation was conducted using especially developed instruments that can be tracked in the electromagnetic field. Another thin-slice CT scan was made postoperatively to assess the result. The evaluation included the position of the screws in the direction of trajectory and any injury to the surrounding cortical bone. The results were classified in 5 groups: grade 1: ideal screw position in the center of the pedicle with no cortical bone injury; grade 2: acceptable screw position, cortical bone injury with cortical penetration ≤ 2 mm; grade 3: cortical bone injury with cortical penetration 2,1-4 mm, grad 4: cortical bone injury with cortical penetration 4,1-6 mm, grade 5: cortical bone injury with cortical penetration >6 mm.The initial evaluation of the system showed good accuracy for the lumbar spine (65% grade 1, 20% grade 2, 15% grade 3, 0% grade 4, 0% grade 5). A comparison of the initial results with other navigation techniques in literature (CT navigation, 2D fluoroscopic navigation) shows that the accuracy of this system is comparable.EMF navigation offers a high accuracy in Pedicle screw placement with additional advantages compared to other techniques. The short set-up time and easy handling of EMF navigation should be emphasized. Additional advantages are the absence of intraoperative radiation exposure for the operator and surgical team in the current set-up and the operator's free mobility without interfering with navigation. Further studies with navigation at higher levels of the spine, larger numbers of cases and studies with control group are planned