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ESRA19-0454 Spinal anesthesia for intestinal occlusion using bupivicaine 0.5% hyperbaric with adjuvant
Background and aimsIntestinal occlusion may be mortal especially if it is accompanied by co-morbidities Spinal anesthesia could be an alternative to general anesthesia sparing cardiac and pulmonary complications.MethodsA 58-year-old woman was admitted to the hospital for intestinal occlusion that occurred 2days previously. She was having abdominal pain, especially in the left side, nausea and vomiting; no gas or no defecation Her weight was 122 kg and height 160 cm. She had hypertension and diabetes mellitus type 2. She was operated 14 times for ombilical hernia and she had one c-section and orif for right shoulder Spinal anesthesia was performed in L2-L3 using bupivicaine 0.5%-3 ml and adrenaline 0.1%-0.1 ml with clonidine 0.075 mg intrathecally The block extension was T8. Hypotension was corrected with ephedrine infusion was with voluven6%-500 ml and normal saline 0.9%-2l.ResultsThe operation went well for 4 hours. Median incision was done and an enteral anastomosis was successfully created. Hemodynamic was stable and the patient went to the wards with an EVA <40 There she was kept NPO and took paracetamol 1 g iv each 6 hours and tramadol 100 mg im when EVA >40. The nasogastric tube was removed on the 4th day and she began to drink water and then liquid food and solid nutrition on the 7th day. She left home on her feet.Abstract ESRA19-0454 Figure 1Abstract ESRA19-0454 Figure 2Abstract ESRA19-0454 Figure 3ConclusionsSpinal anesthesia for abdominal surgery with bupivicaine 0.5%hyperbaric and adjuvant such as adrenaline and clonidine give good anesthesia and analgesia for more than 4 hours.
Journal Article
Novel Trends in Hydrogel Development for Biomedical Applications: A Review
Nowadays, there are still numerous challenges for well-known biomedical applications, such as tissue engineering (TE), wound healing and controlled drug delivery, which must be faced and solved. Hydrogels have been proposed as excellent candidates for these applications, as they have promising properties for the mentioned applications, including biocompatibility, biodegradability, great absorption capacity and tunable mechanical properties. However, depending on the material or the manufacturing method, the resulting hydrogel may not be up to the specific task for which it is designed, thus there are different approaches proposed to enhance hydrogel performance for the requirements of the application in question. The main purpose of this review article was to summarize the most recent trends of hydrogel technology, going through the most used polymeric materials and the most popular hydrogel synthesis methods in recent years, including different strategies of enhancing hydrogels’ properties, such as cross-linking and the manufacture of composite hydrogels. In addition, the secondary objective of this review was to briefly discuss other novel applications of hydrogels that have been proposed in the past few years which have drawn a lot of attention.
Journal Article
Cherry Picking with Synthetic Controls
We evaluate whether a lack of guidance on how to choose the matching variables used in the Synthetic Control (SC) estimator creates specification-searching opportunities. We provide theoretical results showing that specification-searching opportunities are asymptotically irrelevant if we restrict to a subset of SC specifications. However, based on Monte Carlo simulations and simulations with real datasets, we show significant room for specification searching when the number of pre-treatment periods is in line with common SC applications, and when alternative specifications commonly used in SC applications are also considered. This suggests that such lack of guidance generates a substantial level of discretion in the choice of the comparison units in SC applications, undermining one of the advantages of the method. We provide recommendations to limit the possibilities for specification searching in the SC method. Finally, we analyze the possibilities for specification searching and provide our recommendations in a series of empirical applications.
Journal Article
Bioinspired structural hydrogels with highly ordered hierarchical orientations by flow-induced alignment of nanofibrils
Natural structural materials often possess unique combinations of strength and toughness resulting from their complex hierarchical assembly across multiple length scales. However, engineering such well-ordered structures in synthetic materials via a universal and scalable manner still poses a grand challenge. Herein, a simple yet versatile approach is proposed to design hierarchically structured hydrogels by flow-induced alignment of nanofibrils, without high time/energy consumption or cumbersome postprocessing. Highly aligned fibrous configuration and structural densification are successfully achieved in anisotropic hydrogels under ambient conditions, resulting in desired mechanical properties and damage-tolerant architectures, for example, strength of 14 ± 1 MPa, toughness of 154 ± 13 MJ m
−3
, and fracture energy of 153 ± 8 kJ m
−2
. Moreover, a hydrogel mesoporous framework can deliver ultra-fast and unidirectional water transport (maximum speed at 65.75 mm s
−1
), highlighting its potential for water purification. This scalable fabrication explores a promising strategy for developing bioinspired structural hydrogels, facilitating their practical applications in biomedical and engineering fields.
Natural materials can combine strength and toughness, but achieving similar well-ordered structures for synthetic materials is challenging. Here, the authors report hydrogels prepared by flow-induced alignment of nanofibrils, with anisotropic structure and good mechanical properties.
Journal Article
Bone Grafts in Dental Medicine: An Overview of Autografts, Allografts and Synthetic Materials
This review provides an overview of various materials used in dentistry and oral and maxillofacial surgeries to replace or repair bone defects. The choice of material depends on factors such as tissue viability, size, shape, and defect volume. While small bone defects can regenerate naturally, extensive defects or loss or pathological fractures require surgical intervention and the use of substitute bones. Autologous bone, taken from the patient’s own body, is the gold standard for bone grafting but has drawbacks such as uncertain prognosis, surgery at the donor site, and limited availability. Other alternatives for medium and small-sized defects include allografts (from human donors), xenografts (from animals), and synthetic materials with osteoconductive properties. Allografts are carefully selected and processed human bone materials, while xenografts are derived from animals and possess similar chemical composition to human bone. Synthetic materials such as ceramics and bioactive glasses are used for small defects but may lack osteoinductivity and moldability. Calcium-phosphate-based ceramics, particularly hydroxyapatite, are extensively studied and commonly used due to their compositional similarity to natural bone. Additional components, such as growth factors, autogenous bone, and therapeutic elements, can be incorporated into synthetic or xenogeneic scaffolds to enhance their osteogenic properties. This review aims to provide a comprehensive analysis of grafting materials in dentistry, discussing their properties, advantages, and disadvantages. It also highlights the challenges of analyzing in vivo and clinical studies to select the most suitable option for specific situations.
Journal Article
Chameleon-like elastomers with molecularly encoded strain-adaptive stiffening and coloration
Human skin is soft and compliant, but it can quickly become stiff when deformed to prevent injury. Chameleon skin can change color when the animal goes from a relaxed to an excited state. Although these properties can be captured individually in synthetic materials, the combination of different dynamic responses can be hard to control. Vatankhah-Varnosfaderani et al. created triblock copolymers of the ABA variety, where the A blocks have a linear structure and the B blocks are like bottlebrushes. When strained, these polymers stiffened like human skin and changed color, thus giving the materials a range of adaptive properties. Science , this issue p. 1509 Triblock copolymers show strain stiffening and color responses in a material that could be used for adaptive camouflage. Active camouflage is widely recognized as a soft-tissue feature, and yet the ability to integrate adaptive coloration and tissuelike mechanical properties into synthetic materials remains elusive. We provide a solution to this problem by uniting these functions in moldable elastomers through the self-assembly of linear-bottlebrush-linear triblock copolymers. Microphase separation of the architecturally distinct blocks results in physically cross-linked networks that display vibrant color, extreme softness, and intense strain stiffening on par with that of skin tissue. Each of these functional properties is regulated by the structure of one macromolecule, without the need for chemical cross-linking or additives. These materials remain stable under conditions characteristic of internal bodily environments and under ambient conditions, neither swelling in bodily fluids nor drying when exposed to air.
Journal Article
Hydrogel Preparation Methods and Biomaterials for Wound Dressing
Wounds have become one of the causes of death worldwide. The metabolic disorder of the wound microenvironment can lead to a series of serious symptoms, especially chronic wounds that bring great pain to patients, and there is currently no effective and widely used wound dressing. Therefore, it is important to develop new multifunctional wound dressings. Hydrogel is an ideal dressing candidate because of its 3D structure, good permeability, excellent biocompatibility, and ability to provide a moist environment for wound repair, which overcomes the shortcomings of traditional dressings. This article first briefly introduces the skin wound healing process, then the preparation methods of hydrogel dressings and the characteristics of hydrogel wound dressings made of natural biomaterials and synthetic materials are introduced. Finally, the development prospects and challenges of hydrogel wound dressings are discussed.
Journal Article
Designing Artificial Cells towards a New Generation of Biosensors
The combination of biological and synthetic materials has great potential to generate new types of biosensors. Toward this goal, recent advances in artificial cell development have demonstrated the capacity to detect a variety of analytes and environmental changes by encapsulating genetically encoded sensors within bilayer membranes, expanding the contexts within which biologically based sensing can operate. This chassis not only acts as a container for cell-free sensors, but can also play an active role in artificial cell sensing by serving as an additional gate mediating the transfer of environmental information. Here, we focus on recent progress toward stimuli-responsive artificial cells and discuss strategies for membrane functionalization in order to expand cell-free biosensing capabilities and applications.
Advances in synthetic biology have facilitated the development of cell-based and cell-free biosensors, enabling detection of molecular signals ranging from chemical contaminants to disease markers.Artificial cells have emerged as a platform to combine the sensing activities of cell-free sensors with certain membrane functions demonstrated in cell-based sensors, including molecular containment, protectivity, and small molecule gating.Recently, artificial cells have been designed to sense environmental molecules and initiate genetically-encoded responses. These sensors often utilize protein expression of membrane pores to release signaling molecules in response to a received input, facilitating communication with live and artificial cells.Progress in membrane engineering will allow the chassis to serve as an active participant in artificial cell sensing.
Journal Article
Late fall synthetic acaricide application is effective at reducing host-seeking adult and nymphal Ixodes scapularis
Based on increases in reported cases of tick-borne illnesses, expanding ranges of native ticks, and repeated documentation of arrivals of nonnative tick species, there is a clear need for their effective management in the United States. Synthetic acaricides have proven efficacious in tick management, but real/perceived negative impacts to the environment and nontarget, beneficial insects must be addressed. We sought to determine whether late fall synthetic acaricide application, when most susceptible beneficial insects are presumably dormant or have migrated, could effectively manage host-seeking spring Ixodes scapularis Say abundances as compared to traditional spring application. We compared results of delivery of Demand CS (lambda-cyhalothrin) via truck-mounted high-pressure spray and powered backpack blower as well as delivery of granular Demand G to experimental control (water) in peridomestic habitats in fall 2021, spring 2022, and combined fall 2021/spring 2022. High-pressure fall delivery of Demand CS and backpack delivery of Demand G significantly reduced host-seeking adult I. scapularis abundances within-season and the following spring combined by 100% and 94%, respectively. No host-seeking nymphal I. scapularis were documented in spring after fall only, spring only, or fall and spring combined delivery of Demand CS via high-pressure or powered backpack blower. No adult I. scapularis were documented at any time posttreatment on locations that received high-pressure delivery of Demand CS. We conclude that high-pressure delivery of Demand CS in late fall successfully eliminated multiple stages of host-seeking I. scapularis through the following spring while likely limiting exposure of beneficial insects to synthetic pyrethroids.
Journal Article