Obstructive Jaundice Secondary to Pancreatic Head Metastasis of Malignant Amelanotic Melanoma as the First Clinical Manifestation.

Malignant melanoma is commonly known for its high probability of metastasizing to distant organs. Metastases to gastrointestinal tract are well documented, but resulting jaundice is only scarcely seen. We present a case of histologically verified metastasis of amelanotic melanoma to the head of pancreas infiltrating the common bile duct and consequently causing obstructive jaundice which constituted its first clinical manifestation. Multidisciplinary approach is essential in patients with malignant melanoma since early detection of the melanoma or its metastases may improve patients' clinical outcome, especially owing to the use of targeted biological treatment without any delay.

[Non-invasive ventilation]. / Neinvazivní ventilace.

The paper describes the history and the present of non-invasive ventilation, the therapeutic method which plays an essential role in the therapy of acute as well as chronic respiratory illnesses. It focuses on indications and contraindications, adverse effects as well as some pitfalls of this therapy.Key words: non-invasive ventilation (NIV) - respiratory insufficiency.

Bounded Wang tilings with integer programming and graph-based heuristics.

Wang tiles enable efficient pattern compression while avoiding the periodicity in tile distribution via programmable matching rules. However, most research in Wang tilings has considered tiling the infinite plane. Motivated by emerging applications in materials engineering, we consider the bounded version of the tiling problem and offer four integer programming formulations to construct valid or nearly-valid Wang tilings: a decision, maximum-rectangular tiling, maximum cover, and maximum adjacency constraint satisfaction formulations. To facilitate a finer control over the resulting tilings, we extend these programs with tile-based, color-based, packing, and variable-sized periodic constraints. Furthermore, we introduce an efficient heuristic algorithm for the maximum-cover variant based on the shortest path search in directed acyclic graphs and derive simple modifications to provide a 1/2 approximation guarantee for arbitrary tile sets, and a 2/3 guarantee for tile sets with cyclic transducers. Finally, we benchmark the performance of the integer programming formulations and of the heuristic algorithms showing that the heuristics provide very competitive outputs in a fraction of time. As a by-product, we reveal errors in two well-known aperiodic tile sets: the Knuth tile set contains a tile unusable in two-way infinite tilings, and the Lagae corner tile set is not aperiodic.

Case report: Non-thrombotic iliac vein lesion: an unusual cause of unilateral leg swelling in a patient with endometrial carcinoma.

81-year-old female presented with subacute right lower extremity edema due to iliac vein compression by a markedly enlarged external iliac lymph node later identified as newly relapsed metastatic endometrial carcinoma. The patient underwent a full evaluation of the iliac vein lesion and cancer and had an intravenous stent placed with complete resolution of symptoms post-procedure.

Crochet Leads the Way.

The crochetage sign-a notch near the R-wave peak in the inferior leads-in conjunction with right axis deviation, complete or incomplete right bundle branch block, and right ventricular hypertrophy (R/S ratio >1 in lead V1) on 12-lead electrocardiogram are highly suggestive of atrial septal defect. (Level of Difficulty: Intermediate.).

Spontaneous Coronary Artery Dissection Following SARS-CoV-2-Associated Multisystem Inflammatory Syndrome.

Spontaneous coronary artery dissection (SCAD) is an underdiagnosed cause of acute coronary syndrome, myocardial infarction, and sudden cardiac death. During the coronavirus disease 2019 (COVID-19) pandemic, a multisystem inflammatory syndrome (MIS) emerged that is incompletely understood. While the involvement of numerous organ systems has been described, the potential cardiovascular manifestations, such as myocarditis, arterial thrombosis, or SCAD, are particularly worrisome. Here, we present a case of MIS that was preceded by an unremarkable case of COVID-19 and followed by the development of SCAD. This case highlights the importance of furthering our understanding of the potential sequelae of COVID-19 and of the potential relationship between SCAD and MIS.

Predictors of mortality after atrial correction of transposition of the great arteries.

OBJECTIVES: To determine the long-term and transplantation-free survival of all patients after atrial correction of transposition of the great arteries (TGA) in the Czech and Slovak republics, including its preoperative and perioperative determinants. METHODS: Retrospective analysis of all 454 consecutive patients after atrial correction of TGA was performed. Of these, 126 (27.8%) were female, median age at operation was 7.4 months (Q1 5.3; Q3 13.3) and 164 (36.1%) underwent the Mustard procedure. The relationships between age, weight, the complexity of TGA, operative technique, additional surgical procedures, immediate postoperative presence of tricuspid regurgitation and revision procedures during follow-up to major composite outcome, as such defined as long-term and transplantation-free survival, were tested. RESULTS: Early 30-day mortality did not differ between the Mustard (9.76%) and Senning (8.97%) cohorts (p=0.866). The long-term and transplantation-free survival, which differed between the Mustard and Senning cohorts in favour of the Senning procedure (HR 0.43; 95% CI 0.21 to 0.87), was shorter in complex TGA (HR 2.4; 95% CI 1.59 to 3.78) and in complex surgical interventions (HR 3.51; 95% CI 2.31 to 5.56). The immediate presence of at least moderate tricuspid regurgitation after correction was associated with a shorter long-term and transplantation-free survival in the univariate but not in the multivariable model. CONCLUSIONS: The lower long-term survival of patients after an atrial switch operation of TGA in the Czech and Slovak republics is associated with greater complexity of TGA, complex surgical interventions and application of the the Mustard operative procedure.

Bevacizumab Does Not Inhibit the Formation of Liver Vessels and Liver Regeneration Following Major Hepatectomy: A Large Animal Model Study.

BACKGROUND/AIM: Patients with unresectable liver colorectal cancer metastases are treated with neoadjuvant chemotherapy often accompanied by biological therapy aimed at reducing the mass of metastases and thus increasing the chances of resectability. Bevacizumab comprises an anti-VEGF (vascular endothelial growth factor) humanized IgG monoclonal antibody that is used for biological therapy purposes. It acts to inhibit angiogenesis, thereby slowing down the growth of metastases. Due to its being administered systematically, bevacizumab also exerts an effect on the surrounding healthy liver parenchyma and potentially limits the process of neovascularization and thus regeneration of the liver. Since the remnant liver volume forms an important factor in postoperative morbidity and mortality following a major hepatectomy, we decided to study the effect of bevacizumab on vascular and biliary microarchitecture in healthy liver parenchyma and its ability to regenerate following major hepatectomy. MATERIALS AND METHODS: We performed an experiment employing a large animal model where a total of 16 piglets were divided into two groups (8 piglets in the control group and 8 piglets in the experimental group with bevacizumab). All the animals were subjected to major hepatectomy and the experimental group was given bevacizumab prior to hepatectomy. All the animals were sacrificed after 4 weeks. We performed biochemical analyses at regular time intervals during the follow-up period. Histological examination of the liver tissue was performed following sacrifice of the animals. RESULTS: No statistical difference was shown between groups in terms of the biochemical and immunohistochemical parameters. The histological examination of the regenerating liver tissue revealed the higher length density of sinusoids in the experimental group. CONCLUSION: Bevacizumab does not act to impair liver regeneration following hepatectomy.

SARS-CoV-2 Specific Humoral Immune Responses after BNT162b2 Vaccination in Hospital Healthcare Workers.

BACKGROUND: COVID-19 pandemic has led to a loss of human life in millions and devastating socio-economic consequences worldwide. So far, vaccination is the most effective long-term strategy to control and prevent severe COVID-19 disease. The aim of the current study was to evaluate the humoral immune responses raised against the BNT162b2 vaccine in hospital healthcare workers. METHODS: Total number of 173 healthcare workers enrolled in the study. Their blood samples were collected in three different time intervals after the second SARS-CoV-2 vaccination and evaluated by the ELISA method to detect anti-spike protein IgM and IgG antibodies. The baseline characteristics of all participants were collected using questionnaires and were evaluated for finding any significant data. RESULTS: Our results demonstrated that the levels of antibodies were higher in the young group (21-30 years old) and also among male participants. Moreover, the highest levels of antibodies were detected from the group that received the third shot vaccination. CONCLUSIONS: Our results indicate that age, gender and third-dose vaccination can affect the levels of humoral immune responses against the BNT162b2 vaccine in healthcare workers.

Phase-Field Fracture Modelling of Thin Monolithic and Laminated Glass Plates under Quasi-Static Bending.

A phase-field description of brittle fracture is employed in the reported four-point bending analyses of monolithic and laminated glass plates. Our aims are: (i) to compare different phase-field fracture formulations applied to thin glass plates, (ii) to assess the consequences of the dimensional reduction of the problem and mesh density and refinement, and (iii) to validate for quasi-static loading the time-/temperature-dependent material properties we derived recently for two commonly used polymer foils made of polyvinyl butyral or ethylene-vinyl acetate. As the nonlinear response prior to fracture, typical of the widely used Bourdin-Francfort-Marigo model, can lead to a significant overestimation of the response of thin plates under bending, the numerical study investigates two additional phase-field fracture models providing the linear elastic phase of the stress-strain diagram. The typical values of the critical fracture energy and tensile strength of glass lead to a phase-field length-scale parameter that is challenging to resolve in the numerical simulations. Therefore, we show how to determine the fracture energy concerning the applied dimensional reduction and the value of the length-scale parameter relative to the thickness of the plate. The comparison shows that the phase-field models provide very good agreement with the measured stresses and resistance of laminated glass, despite the fact that only one/two cracks are localised using the quasi-static analysis, whereas multiple cracks evolve during the experiment. It was also observed that the stiffness and resistance of the partially fractured laminated glass can be well approximated using a 2D plane-stress model with initially predefined cracks, which provides a better estimation than the one-glass-layer limit.

A Model of the Action of the Shockwave Generated by a Multichannel Discharge on the Union of Bone Tissue with Bone Cement.

BACKGROUND: In reoperation of femoral prostheses, there is a higher percentage of complications associated with the extraction of bone cement from the femoral channel, which is technically and time consumingly tedious. Shockwaves have been used in medicine for years, particularly in urology for the destruction of concretions and orthopaedics, as a method of treating pain in patients with calcifying enthesopathy. MATERIALS AND METHODS: We studied the use of shockwaves generated by a new source based on the multichannel discharge principle in facilitating extraction of bone cement. Femurs of experimental minipigs were chosen as models. We implanted bone cement into the femoral channel and subsequently applied shockwaves. We then measured the force necessary to extract bone cement. RESULTS: The results indicate that the force necessary for extracting cement was consistently statistically significantly lower in the group treated with multichannel discharge shockwaves compared to that for the controls.

In vivo effects of focused shock waves on tumor tissue visualized by fluorescence staining techniques.

Shock waves can cause significant cytotoxic effects in tumor cells and tissues both in vitro and in vivo. However, understanding the mechanisms of shock wave interaction with tissues is limited. We have studied in vivo effects of focused shock waves induced in the syngeneic sarcoma tumor model using the TUNEL assay, immunohistochemical detection of caspase-3 and hematoxylin-eosin staining. Shock waves were produced by a multichannel pulsed-electrohydraulic discharge generator with a cylindrical ceramic-coated electrode. In tumors treated with shock waves, a large area of damaged tissue was detected which was clearly differentiated from intact tissue. Localization and a cone-shaped region of tissue damage visualized by TUNEL reaction apparently correlated with the conical shape and direction of shock wave propagation determined by high-speed shadowgraphy. A strong TUNEL reaction of nuclei and nucleus fragments in tissue exposed to shock waves suggested apoptosis in this destroyed tumor area. However, specificity of the TUNEL technique to apoptotic cells is ambiguous and other apoptotic markers (caspase-3) that we used in our study did not confirmed this observation. Thus, the generated fragments of nuclei gave rise to a false TUNEL reaction not associated with apoptosis. Mechanical stress from high overpressure shock wave was likely the dominant pathway of tumor damage.

Efficacy and tolerability of delapril plus indapamide versus lisinopril plus hydrochlorothiazide combination treatments in mild to moderate hypertension: a multicenter, randomized clinical study.

BACKGROUND: Several studies have shown that antihypertensive monotherapy is commonly insufficient to control blood pressure (BP) in hypertensive patients and that concomitant use of ≥2 drugs is necessary in ∼50% of these patients. The combination of an angiotensin-converting enzyme (ACE) inhibitor and a diuretic, delapril plus indapamide (D + I), has been shown to be effective and tolerable, with no interaction between the 2 components. Another widely used combination of ACE inhibitor and diuretic is lisinopril plus hydrochlorothiazide (L + H). OBJECTIVES: The aims of this study were to confirm the antihypertensive efficacy and tolerability of the fixed combination of D + I in mild to moderate hypertension, and to compare its therapeutic efficacy and tolerability with that of L + H. METHODS: The antihypertensive efficacy and tolerability of a fixed combination of D + I (30-mg + 2.5-mg tablets once daily) or L + H (20-mg + 12.5-mg tablets once daily) in patients with mild to moderate hypertension were compared in a multinational, multicenter, randomized, 2-armed, parallel-group study. Eligible patients were aged 18 to 75 years and had a diastolic blood pressure (DBP) 95 to 115 mm Hg and a systolic blood pressure (SBP) ≤180 mm Hg, both measured in the sitting position. After a single-blind, placebo run-in period of 2 weeks, patients were randomized to receive 1 of the 2 treatments for a 12-week period. The primary efficacy end point was the BP normalization rate (ie, the percentage of patients with a sitting DBP ≤90 mm Hg) after 12 weeks of treatment. Secondary end points were as follows: (1) the responder rate (ie, the percentage of patients whose sitting DBP was reduced by ≥10 mm Hg from baseline or had a DBP ≤90 mm Hg after 12 weeks of treatment), (2) the percentage of patients with a DBP ≤85 mm Hg, and (3) changes in sitting SBP and DBP after 4, 8, and 12 weeks of treatment. RESULTS: A total of 159 hypertensive patients (88 women, 71 men) were randomized to receive D + I (44 women, 36 men; mean [SD] age, 53 [(11)] years) or L + H (44 women, 35 men; mean [SD] age, 55 [(10)] years). No significant between-group differences were found in any of the primary or secondary end points of the study. Both combinations induced a significant reduction in sitting DBP and SBP from baseline (P<0.001 for both groups at week 12), without significant differences between the groups. Five mild to moderate adverse drug reactions (ADRs) occurred in each treatment group. No patient dropped out of the study because of an ADR. CONCLUSION: This study showed no difference between D + I and L + H interms of antihypertensive efficacy or tolerability in patients with mild to moderate hypertension.

Aperiodic compression and reconstruction of real-world material systems based on Wang tiles.

The paper presents a concept to compress and synthesize complex material morphologies that is based on Wang tilings. Specifically, a microstructure is stored in a set of Wang tiles and its reconstruction is performed by means of a stochastic tiling algorithm. A substantial part of the study is devoted to the setup of optimal parameters of the automatic tile design by means of parametric studies with statistical descriptors at heart. The performance of the method is demonstrated on four two-dimensional two-phase target systems, monodisperse media with hard and soft disks, sandstone, and high porosity metallic foam.

Compressing random microstructures via stochastic Wang tilings.

This Rapid Communication presents a stochastic Wang tiling-based technique to compress or reconstruct disordered microstructures on the basis of given spatial statistics. Unlike the existing approaches based on a single unit cell, it utilizes a finite set of tiles assembled by a stochastic tiling algorithm, thereby allowing to accurately reproduce long-range orientation orders in a computationally efficient manner. Although the basic features of the method are demonstrated for a two-dimensional particulate suspension, the present framework is fully extensible to generic multidimensional media.