Teaching mesenteric principles
John Calvin Coffey, Rishabh Sehgal, Dara Walsh in Mesenteric Principles of Gastrointestinal Surgery, 2017
mesenteric continuity and contiguity means that peritonotomy, mesofascial separation, and mesenterectomy are key activities required for excision, at any level distal to the duodenojejunal flexure. However, continuity presents an educational challenge in that there are no boundaries delimiting continuous regions of the peritoneum, the colon, and the associated mesentery. Moreover, when the gastromesenteric complex is resected intraoperatively, the shape it adopts bares little if any resemblance to the shape it had in the abdomen [2,8]. Digital sculpting provides an opportunity to overcome these issues. Using digital methodologies such as ZBrush (Pixologic, Los Angeles, Unites States), Cinema 4D (Maxon Computer Ltd., Bedford, United Kingdom), Maya (Maya Digital Studios, Mumbai, India), and RenderMan (Pixar, California, United States), it is possible to generate high-fidelity mesenteric models that can be regionally colored, deformed, and sectioned (Figure 10.1) [12]. In keeping with this, a digital atlas of the mesentery, colon, and peritoneum was generated (Chapter 2). The educational value of these models is illustrated in the chapter on flexures (Chapter 20), where the flexures were conceptually excised to demonstrate the relationships between anatomic components (i.e., peritoneal reflection, colon, and mesentery).
Hands
Tor Wo Chiu in Stone’s Plastic Surgery Facts, 2018
The common choice is a non-absorbable monofilament (e.g. Prolene®, easier to use but in vitro tests have shown stretching under tension leading to a tendon gap) or non-absorbable braided (Ticron®, braided sutures have a tendency to cause deformation and need greater attention to detail in their placement and tightening). Absorbable sutures (PDS, Maxon®) are not commonly used but can also be satisfactory since the metabolic rate of the tendon tissue is low, and suture material is retained long enough to maintain tensile strength during healing.
Degradable, biodegradable, and bioresorbable polymers for time-limited therapy
Yoshinobu Onuma, Patrick W.J.C. Serruys in Bioresorbable Scaffolds, 2017
Many other biocompatible degradable copolymers derived from lactides and/or glycolide and other monomers are present in the literature and have been proposed to make various therapeutic devices that have a potential for applications as degradable material. Some have reached the level of clinical application and commercialization like Maxon® sutures made of PGA-co-TMC (trimethylene carbonate). Some others like PLA-PEO-PLA (PEO = poly[ethylene oxide]) have a potential for effective applications as drug delivery systems or as scaffolds in tissue engineering [14].
Cost and outcome of a community-based paediatric hearing screening programme in rural India with application of tele-audiology for follow-up diagnostic hearing assessment
Published in International Journal of Audiology, 2018
Vidya Ramkumar, K. R. John, K. Selvakumar, C. S. Vanaja, Roopa Nagarajan, James W. Hall
Based on some studies of costs associated with universal newborn hearing screening programmes in hospitals, the estimated cost per infant screened is between $13 and $33 depending mainly on the salaries of the persons involved in the programme (Maxon et al. 1995; Kezirian et al. 2001; Vohr et al. 2001). Other researchers used actual cost incurred and included fringe cost, salary of all personnel including the screeners, clerical staff, secretarial staff, coordinators and audiologist (Maxon et al. 1995). Still other studies used modelling and assumptions to estimate costs, including time costs (Vohr et al. 2001). Still, overall UNHS programmes may be profitable even at the most expensive budget of $35 per child screened, since the expenses is less than the supplementary costs of rehabilitation for late identified infant hearing loss (Cao-Nguyen, Kos, and Guyot 2007). The sensitivity analysis in our study showed that the lowest cost per child screened of $23 satisfies this argument. In one hospital-based hearing screening programme in India, a very low cost of approximately $5 per AABR screening was reported (Gupta et al. 2015). However, unlike the present study, the costs associated with diagnostic testing was not included to estimate cost per infant screened, which explains the much lower estimate.
The effect of horizontal forces from a Smart Walker on gait and perceived exertion
Published in Assistive Technology, 2022
Wen Liang Yeoh, Jeewon Choi, Ping Yeap Loh, Seiji Saito, Satoshi Muraki
The motors used were Maxon EC 45 flat brushless DC motors with integrated encoders and 15:1 planetary gearhead (Maxon Motor, Switzerland). The motors were controlled using a TMS320F28379D Launchpad microcontroller and two BOOSTXL-DRV8301 (Texas Instruments, USA) motor drivers. Power was supplied through a 24 V switched-mode power supply, the RWS600B-24 (TDK, Japan), connected to the mains using extension cables. Additionally, external braking resistors were connected parallel to the power supply and regulated using a MOSFET switch to dissipate the regenerative energy generated when braking.
Clonal evolution in a chronic neutrophilic leukemia patient
Published in Hematology, 2019
Qi-Guo Zhang, Jing Wang, Wen-Yu Gong, Qi-Chuan Jin
The current study, first, confirms the observations by Maxon et al. [1] regarding the association between CNL and CSF3R mutations. Second, it presents a complete picture of the mutational profiling of the pathogenesis of CNL, which is certainly more complex than expected from previous reports. Approximately 75% of patients with CNL who have CSF3R mutations exhibit only membrane-proximal mutations, whereas the other 25% of patients harbor both membrane-proximal and truncating-compound mutations [3]. The scarcity of truncation mutations alone in CNL raises the possibility that truncation mutations alone are insufficient to drive the malignancy and that cooperating mutations in CSF3R or other genes may be required [4]. The CSF3R truncation mutation is not sufficient for leukemia but represents an early event in leukemogenesis. Truncation mutations alone do not cause leukemia in mouse models [5], but they can accelerate the development of disease in the presence of another genetic event driving leukemia [6]. Consistent with the in vivo data, the CSF3R truncation mutations display slower cell transformation kinetics than the T618I mutation in cellular assays and require ligands for the activation of downstream signaling pathways [1,7], which reduces the differentiative capacity of the receptor while continuing to allow for cellular proliferation. In our case, truncation mutations in the SRSF2 and TET2 genes are sufficient to drive leukemogenesis in the CNL, and CSF3R membrane-proximal mutations occur as a secondary event within the context of clonal hematopoiesis. The process of clonal hematopoiesis is originally associated with somatically acquired variants in genes that regulate epigenetic (TET2) and splicing (SRSF2) processes. Acquisition of a CSF3R signaling mutation gives the clonal hematopoietic population a neutrophil lineage bias. Because patients with CNL who have only truncation mutations in CSF3R are apparently rare, it seems likely that the clone evolves to acquire additional mutations in epigenetic and splicing genes, which amplify the disease process. Interestingly, concomitant SRSF2 and TET2 mutations were not observed in any other CNL cases, though this was not statistically significant [8]. These mutations may provide a backdrop for a later-occurring CSF3R mutation, which, in turn, imparts a neutrophilic phenotype resulting in CNL.
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