Finite element modeling of maximum stress in pelvic floor structures during the head expulsion (FINESSE) study.

INTRODUCTION AND HYPOTHESIS: Several studies have assessed birth-related deformations of the levator ani muscle (LAM) and perineum on models that depicted these elements in isolation. The main aim of this study was to develop a complex female pelvic floor computational model using the finite element method to evaluate points and timing of maximum stress at the LAM and perineum in relation to the birth process. METHODS: A three-dimensional computational model of the female pelvic floor was created and used to simulate vaginal birth based on data from previously described real-life MRI scans. We developed three models: model A (LAM without perineum); model B (perineum without LAM); model C (a combined model with both structures). RESULTS: The maximum stress in the LAM was achieved when the vertex was 9 cm below the ischial spines and measured 37.3 MPa in model A and 88.7 MPa in model C. The maximum stress in the perineum occurred at the time of distension by the suboocipito-frontal diameter and reached 86.7 MPa and 119.6 MPa in models B and C, respectively, while the stress in the posterior fourchette caused by the suboccipito-bregmatic diameter measured 36.9 MPa for model B and 39.8 MPa for model C. CONCLUSIONS: Including perineal structures in a computational birth model simulation affects the level of stress at the LAM. The maximum stress at the LAM and perineum seems to occur when the head is lower than previously anticipated.

A new musculoskeletal AnyBody™ detailed hand model.

Musculoskeletal research questions regarding the prevention or rehabilitation of the hand can be addressed using inverse dynamics simulations when experiments are not possible. To date, no complete human hand model implemented in a holistic human body model has been fully developed. The aim of this work was to develop, implement, and validate a fully detailed hand model using the AnyBody Modelling System (AMS) (AnyBody, Aalborg, Denmark). To achieve this, a consistent multiple cadaver dataset, including all extrinsic and intrinsic muscles, served as a basis. Various obstacle methods were implemented to obtain with the correct alignment of the muscle paths together with the full range of motion of the fingers. These included tori, cylinders, and spherical ellipsoids. The origin points of the lumbrical muscles within the tendon of the flexor digitorum profundus added a unique feature to the model. Furthermore, the possibility of an entire patient-specific scaling based on the hand length and width were implemented in the model. For model validation, experimental datasets from the literature were used, which included the comparison of numerically calculated moment arms of the wrist, thumb, and index finger muscles. In general, the results displayed good comparability of the model and experimental data. However, the extrinsic muscles showed higher accordance than the intrinsic ones. Nevertheless, the results showed, that the proposed developed inverse dynamics hand model offers opportunities in a broad field of applications, where the muscles and joint forces of the forearm play a crucial role.

A Sensor System for Detecting and Localizing Partial Discharges in Power Transformers with Improved Immunity to Interferences.

The paper reports on the solution, principles, and application results related to a system for diagnosing main transformers in power plants via the radiofrequency method. The subject of the diagnostics is the occurrence of partial discharge activity in transformers. The technical solution of the system is characterized in the introductory section of the article. There then follows a description of the operating principle and the implemented novel advanced methods for signal detection and source localization. The results obtained from practical application of the system within the diagnostics of high-power transformers are presented as well. Because ambient electromagnetic disturbance was recognized as a major issue during the system development, novel detection methods were proposed, implemented, and verified. The principal approach utilizes an external radiofrequency sensor to detect outer impulse disturbance and to eliminate disturbance-triggered acquisitions, and it also ensures direct real-time visualization of the desired impulse signals. The ability of weak signal detection was verified via artificial impulse signal injection into the transformer. The developed detection methods were completed with localization techniques for signal source estimation. The desired impulse signal was detected and localized during full operation of the main transformer, despite the presence of strong electromagnetic interference.

[Variability of the deep femoral venous system]. / Variabilita hlubokých zil stehna.

Deep venous system is known for its extreme variability but in anatomy it receives only marginal interest. Although a few previous anatomical studies have already pointed out the fact of a significant discrepancy between the autopsy findings and the literary description, it has not had any particular output so far. Our findings confirmed the deep femoral vein to be an alternative collateral vein connecting the popliteal with the femoral vein.

Quantification of compact bone microporosities in the basal and alveolar portions of the human mandible using osteocyte lacunar density and area fraction of vascular canals.

Based on the orientation of the osteons, the basal portion and the alveolar portion of the body of the human mandible can be distinguished. In the compact bone, two types of microporosities can be quantified, the osteocyte lacunae and the vascular canals. Our aim was (i) to perform three-dimensional reconstruction of osteocyte lacunae to suggest an efficient means of sampling to estimate their numerical density and (ii) to compare bone microporosities in the basal and the alveolar portions of ten mandibles. Using optical disector, we estimated the density of osteocyte lacunae, and using a stereological point-counting technique, we quantified the area fraction of the vascular canals. The diameter of the lacunae was 14±3µm. While the fraction of vascular canals was comparable in both parts of the body of the mandible, the numerical density of osteocyte lacunae was higher (p=0.007) in the alveolar portion (17056±1264/mm(3)) than in the basal portion (14522±665/mm(3)). The lacunar and vascular microporosities were statistically independent of each other. As this is the first three-dimensional counting of osteocyte lacunae, we discuss the relation of this parameter to the biomechanics of the mandible, and we compare our data with previously used two-dimensional methods. We present an efficient sampling method that is useful for the histological description of bone microporosities. When taking into account the spatial characteristics of lacunae, the locally specific numerical density of lacunae can be easily assessed with the three-dimensional counting method, which is not biased by the variation in size and orientation of the lacunae.

Synthetic diffractive elements for security applications realized on an enhanced integral dot-matrix system.

One of the important fields of application of synthetic diffractive structures is optical document security. Several methods of security enhancement of diffractive elements for security applications are presented, namely, high carrier-frequency cryptograms and noise-covered elements are introduced. Structures are designed with respect to the fabrication on special enhanced integral dot-matrix system.

Expression of apoptosome pathway-related transcripts in non-small cell lung cancer.

PURPOSE: Tumour cells killing by cytotoxic therapies largely depends on triggering the intrinsic apoptosome-mediated caspase activation pathway but it had never been evaluated whether the expression of transcripts encoding the core components of apoptosome pathway is altered in non-small cell lung carcinoma (NSCLC). METHODS: We investigated the expression status of several apoptosome pathway-related transcripts including Apaf-1, procaspase-9, -3, -6, -7 and Smac in tumour and lung tissue samples from 65 surgically treated NSCLC patients and in 10 NSCLC cell lines with using real time RT-PCR. RESULTS: NSCLC tissues and cell lines showed significantly increased expression of procaspase-9, -3, -6 and Smac mRNAs as compared to the lungs and expression of these transcripts was simultaneously upregulated in a subset of NSCLCs belonging to different histopathological type, grade and stage categories. The expression of procaspase-7 mRNA in NSCLC tissues and cell lines and lungs was not significantly different. By contrast, the expression of Apaf-1 mRNA was frequently downregulated in the tumours as compared to matched lungs. Nevertheless, the examined NSCLC cell lines showed significantly higher expression of Apaf-1 mRNA than the lungs. The expression of Apaf-1, procaspase-9 and -6 mRNAs was higher in lung adenocarcinomas as compared to squamous cell lung carcinomas but the expression levels of the studied apoptosome pathway-related transcripts in the tumours were independent of tumour's grade and stage. CONCLUSIONS: The results of the present study suggest that there is a subgroup of NSCLCs, which may be intrinsically primed for apoptosis through upregulated expression of transcripts encoding the apoptosome pathway components.

Concurrent versus sequential chemoradiotherapy with cisplatin and vinorelbine in locally advanced non-small cell lung cancer: a randomized study.

PURPOSE: The superiority of chemoradiotherapy (CRT) over radiation alone in locally advanced non-small cell lung cancer (NSCLC) has been proven, but the relative merits of a concurrent schedule versus their sequential administration are less clear. This study compared the safety and efficacy of concurrent and sequential CRT, with chemotherapy (CT) consisting of a cisplatin and vinorelbine regimen, in patients with locally advanced NSCLC. PATIENTS AND METHODS: One hundred and two previously untreated patients (aged 42-75 years) with locally advanced, stage IIIA (n = 15) or stage IIIB (n = 87) NSCLC were entered into the study. The CT schedule consisted of up to four cycles of cisplatin 80 mg/m(2) on day 1, and vinorelbine 25 mg/m(2) at the first and fourth cycles (12.5 mg/m(2) during the 2nd/3rd cycles) on days 1, 8, 15 of a 28-day cycle. Radiotherapy (RT) was prescribed at a dose of 60 Gy/30 fractions, given as five fractions per week for 6 weeks. In the concurrent arm (arm A), RT was started on day 4 of cycle 2; whilst in the sequential arm (arm B), RT started within 2 weeks after completion of CT. Fifty-two patients were randomized to concurrent treatment and 50 to the sequential schedule. RESULTS: Overall survival was significantly longer in arm A (median survival 16.6 months) versus arm B (median survival 12.9 months) (P = 0.023 by means of log-rank test; hazard ratio HR = 0.61, 95% CI of HR (0.39-0.93)), and time to progression (TTP) was also significantly longer in arm A (median time to progression 11.9 months) versus arm B (median time to progression 8.5 months) (P = 0.024 by means of log-rank test; HR = 0.62, 95% CI of HR (0.38-0.93)). Ninety-eight patients were evaluable for response and 101 for toxicity. The overall response rate was significantly higher in arm A, 80% (with 21% complete response (CR)) compared with 47% (with 17% CR) in arm B (P = 0.001 by means of chi(2)-test). WHO grade 3 or 4 toxicity was more frequent in arm A than in arm B, with a significantly greater incidence of leucopenia (53% versus 19%, P = 0.009 by means of chi(2) test) and nausea/vomiting (39% versus 15%, P = 0.044 by means of chi(2) test). There were no treatment related deaths. CONCLUSION: In this study population, concurrent CRT demonstrated significant benefit in terms of response rate, overall survival and time to progression over sequential CRT. The concurrent CRT schedule was associated with higher toxicity; however, the adverse event profile was acceptable in both arms.

Increased expression of Apaf-1 and procaspase-3 and the functionality of intrinsic apoptosis apparatus in non-small cell lung carcinoma.

The intrinsic apoptosis apparatus plays a significant role in generating and amplifying cell death signals. In this study we examined whether there are differences in the expression of its components and in its functioning in non-small cell lung carcinoma (NSCLC) and the lung. We show that NSCLC cell lines express Apaf-1 and procaspase-9 and -3 proteins and that the expression of Apaf-1 and procaspase-3, but not of procaspase-9 and -7, is frequently up-regulated in NSCLC tissues as compared to the lung. NSCLC tissues and lungs and some NSCLC cell lines expressed also caspase-9S(b) and displayed a high caspase-9S(b)/procaspase-9 expression ratio. Procaspase-3 from NSCLCs and lungs was readily processed to caspase-3 by granzyme B or caspase-8, and the granzyme B-generated caspase-3-like activity was significantly higher in tumor tissues and cells than in lungs. By contrast, cytochrome c plus dATP could induce a significant increase of caspase-3-like activity in cytosol only in some NSCLC cell lines and in subsets of studied NSCLC tissues and lungs, while procaspase-3 and -7 were detectably processed only in NSCLC tissues which showed a high (cytochrome c+dATP)-induced caspase-3-like activity. Taken together, the present study provides evidence that the expression of Apaf-1 and procaspase-3 is up-regulated in NSCLCs and indicates that the tumors have a capability to suppress the apoptosome-driven caspase activation in their cytosol.