A Simulation Analysis of Maternal Pelvic Floor Muscle

Pelvic floor disorder (PFD) is a common disease affecting the quality of life of middle-aged and elderly women. Pelvic floor muscle (PFM) damage is related to delivery mode, fetal size, and parity. Spontaneous vaginal delivery causes especially great damage to PFM. The purpose of this study was to summarize the characteristics of PFM action during the second stage of labor by collecting female pelvic MRI (magnetic resonance imaging) data and, further, to try to investigate the potential pathogenetic mechanism of PFD. A three-dimensional model was established to study the influence factors and characteristics of PFM strength. In the second stage of labor, the mechanical responses, possible damage, and the key parts of postpartum lesions of PFM due to the different fetal biparietal diameter (BPD) sizes were analyzed by finite element simulations. The research results showed that the peak stress and strain of PFM appeared at one-half of the delivery period and at the attachment point of the pubococcygeus to the skeleton. In addition, during the simulation process, the pubococcygeus was stretched by about 1.2 times and the levator ani muscle was stretched by more than two-fold. There was also greater stress and strain in the middle area of the levator ani muscle and pubococcygeus. According to the statistics, either being too young or in old maternal age will increase the probability of postpartum PFM injury. During delivery, the entire PFM underwent the huge deformation, in which the levator ani muscle and the pubococcygeus were seriously stretched and the attachment point between the pubococcygeus and the skeleton were the places with the highest probability of postpartum lesions.

Validity and Effects of Placement of Velocity-Based Training Devices

Velocity-based training (VBT) is a resistance training method by which training variables are manipulated based on kinematic outcomes, e.g., barbell velocity. The better precision for monitoring and manipulating training variables ascribed to VBT assumes that velocity is measured and communicated correctly. This study assessed the validity of several mobile and one stationary VBT device for measuring mean and peak concentric barbell velocity over a range of velocities and exercises, including low- and high-velocity, ballistic and non-ballistic, and plyometric and non-plyometric movements, and to quantify the isolated effect of device attachment point on measurement validity. GymAware (r = 0.90–1, standard error of the estimate, SEE = 0.01–0.08 m/s) and Quantum (r = 0.88–1, SEE = 0.01–0.18 m/s) were most valid for mean and peak velocity, with Vmaxpro (r = 0.92–0.99, SEE = 0.02–0.13 m/s) close behind. Push (r = 0.69–0.96, SEE = 0.03–0.17 m/s) and Flex (r = 0.60–0.94, SEE = 0.02–0.19 m/s) showed poorer validity (especially for higher-velocity exercises), although typical errors for mean velocity in exercises other than hang power snatch were acceptable. Effects of device placement were detectable, yet likely small enough (SEE < 0.1 m/s) to be negligible in training settings.

4,5,6,7-Tetrahydroindol-4-Ones as a Valuable Starting Point for the Synthesis of Polyheterocyclic Structures

This review focuses on the synthesis of polyheterocyclic structures with a variety of medicinal and optoelectronic applications, starting from readily available 4,5,6,7-tetrahydroindol-4-one analogs. First, routes toward the 4,5,6,7-tetrahydroindol-4-one starting materials are summarized, followed by synthetic pathways towards polyheterocyclic structures which are categorized based on the size and attachment point of the newly formed (hetero)cyclic ring.

Selection of interlocking side mills based on modeling thermodynamic processes during cutting. Part 1. Modeling the conditions of contact interaction

The results of research on improving the design of wood-cutting mills are presented. A model of interaction of elements of an assembled cutting tool has been developed to select its structure at the design stage. Initial data and conditions of contact interaction are obtained for modeling thermodynamic processes in the knife attachment unit. Keywords: easy-to-work material, wood-cutting interlocking side mill, attachment point, cutting element, conditions of contact interaction. [email protected]

Clinical and Radiographic Outcomes of Cervical Open-Door Laminoplasty Withmodified Centerpiece Mini-Plate Fixation and Extensor Attachment Point Reconstruction in Treating Cervical Spondylotic Myelopathy

ObjectiveThis retrospective study aimed to investigate the clinical and radiographic outcomes of open-door laminoplasty with modified centerpiece mini-plate fixation and extensor attachment point reconstruction for treating cervical spondylotic myelopathy (CSM).MethodSixty-nine patients with CSM, who underwent C3-7 open-door laminoplasty in our hospital from January 2016 to May 2017, were divided into two groups: group A underwent surgery with a modified centerpiece titanium plate and group B underwent surgery with a conventional centerpiece titanium plate. Changes in cervical spinal angle (CSA), cervical range of motion (ROM), atrophy of posterior cervical muscles, and neurological function (Japanese Orthopaedic Association [JOA] score) and the occurrence of axial symptoms (AS) were compared between the groups.ResultThere were no significant differences in operative time, intra-operative blood loss, lamina open angle, and spinal cord drift distance between the groups. After the surgery, JOA score significantly increased (P < 0.05), neurological recovery rates were similar (62.7% vs. 63.4%), cervical ROM did not significantly change when compared with the preoperative level (P > 0.05) in both groups; CSA and cross-sectional area of the posterior cervical muscles decreased significantly in group B (P < 0.05) but not in group A (P > 0.05), and postoperative AS were significantly more severe in group B than in group A (P < 0.05).ConclusionOpen-door laminoplasty is an effective surgical procedure for CSM. The application of modified centerpiece mini-plate fixation effectively reconstructs the posterior extensor attachment points, which reduces posterior cervical muscle atrophy, maintains cervical curvature, and reduces the occurrence of axial symptoms.

Biomimetic enterobactin analogue mediates iron-uptake and cargo transport into E. coli and P. aeruginosa

The design, synthesis and biological evaluation of the artificial enterobactin analogue EntKL and several fluorophore-conjugates thereof are described. EntKL provides an attachment point for cargos such as fluorophores or antimicrobial...

A New Posterior Extensor Attachment-Point Reconstruction Technique for Cervical Spondylotic Myelopathy Involving C2 Segment: Clinical Outcome and Safety

Background and Study Aim Cervical spondylotic myelopathy (CSM) is a common degenerative disease that mainly occurs in elder patients, leading to different degrees of neurological dysfunction. Spinal cord involvement is mainly distributed at the C3–C7 segments, but it may also involve up to the C2 level. This study aimed to assess the clinical efficacy and safety of open-door laminoplasty using a new extensor attachment-point reconstruction technique for treating CSM involving the C2 segment. Patients and Methods Fifty-nine patients with CSM involving the C2 segment and undergoing open-door laminoplasty were included in this retrospective study. Based on the titanium plate used in the operation, patients were divided into two groups, a reconstructed titanium plate fixation (RPF) group (n = 28) and a conventional titanium plate fixation (CPF) group (n = 31). Improvements in neurological function, cervical range of motion (ROM), cervical curvature index (CCI), preservation of posterior cervical muscle mass, and axial symptoms were compared between the two groups. Results There were no significant differences in operative time and intraoperative blood loss between the groups (p > 0.05). The Japanese Orthopaedic Association (JOA) score significantly increased in both groups postsurgery (p < 0.05); the neurological recovery rate was similar between the two groups (64.1 ± 13.3% vs. 65.9 ± 14.7%, p > 0.05). There was no significant loss of cervical ROM in either group (p > 0.05). The anteroposterior dural sac diameter at the C2 level was significantly enlarged in both groups (p < 0.05). Alternatively, CCI was significantly reduced in the CRP group (p < 0.05) but unchanged in the RPF group (p > 0.05). The cross-sectional area of the posterior cervical muscles was also significantly reduced in the CPF group (p < 0.05) but maintained in the RPF group (p > 0.05). Finally, axial symptoms were more severe in the CPF group than in the RPF group (p < 0.05). Conclusion Laminoplasty is an effective surgical procedure for CSM involving the C2 segment. The reconstructed titanium plate achieved superior maintenance of cervical curvature and reduced both muscle atrophy and severity of axial symptoms compared with titanium conventional plates.

Can Primary Cardiac Myxofibrosarcoma Grow Quickly from Zero to a Size Leading to Left-Sided Heart Failure within 9 Months?

Malignant cardiac tumors are extremely rare, representing only 25% of all cardiac tumors, and angiosarcoma is the most common subtype. Myxofibrosarcomas are one of the rarest forms of cardiac malignant tumors. These tumors can silently grow and produce no or few symptoms until the tumor is large enough to obstruct blood flow. The definitive treatment is negative margin resection, if possible. Most cardiac tumors have a limited response to chemotherapy and radiotherapy. Therefore, surgical treatment is considered the best option. Our patient is a 57-year-old Caucasian postmenopausal female who presented with dyspnea, shortness of breath, and fatigue. Echocardiography confirmed the presence of a mass in the left atrium. A median sternotomy was performed with aortic and bicaval cannulation. Right atriotomy was performed, and the left atrium was exposed through the transseptal approach. A rounded smooth-surfaced mass was found in the left atrium that was 3.5 × 4.5 cm in size. The mass had a prominent and firm attachment point with a wide-based stalk in the pulmonary vein-right atrium border area. The tumor was completely excised, and the excision point was strengthened with a running suture. The following pathologic diagnosis was finally made: myxofibrosarcoma, FNCLCC (National Federation of Cancer Centres) Grade 2. Immunohistochemistry showed positivity for Epithelial membrane antigen (EMA), desmin, calretinin, Ki67, Smooth Muscle Actin (SMA), and S100. Given the rarity of cardiac malignant tumors, we thought preoperatively that this particular tumor could be a myxoma although it did not have the classical attachment point with a stalk at the interatrial septum. Our case is an example of how fast a cardiac sarcoma can grow. Nine months before the presentation, the patient underwent an echocardiography that did not show any signs of tumor growth. The estimated time of growth was 9 months or less. We followed our patient, performing a computer tomography scan and echocardiography 1 month after surgery, and these did not show any signs of tumor growth.