A rare clinical case of extra-gastrointestinal stromal pancreatic tumor

Extra-gastrointestinal stromal tumors arising from the pancreas are extremely rare. To date, just over 30 cases have been described in the world literature. A clinical observation of a 67-year-old patient with dull epigastric pain and a large cystic solid neoplasm instrumentally identified as an extra-gastrointestinal stromal tumor of the head of the pancreas is presented. The volume of surgical intervention consisted of pancreatogastroduodenectomy and right-sided hemicolectomy, since tumor invasion into the transverse mesocolon was detected intraoperatively. The final diagnosis of extra-gastrointestinal stromal sarcoma of the head of the pancreas with invasion into the mesocolon pT4N0M0, stage IIIb was made on the basis of histopathology and immunohistochemistry results.

Giant inflammatory pseudotumor of the lung: a case report

The inflammatory myofibroblastic tumor, which was first described in 1939, is a rare neoplasm that accounts for 0.04%-0.7% of all lung neoplasms. These neoplasms occur most often in children, as they are the most common primary lung tumors in children. Preoperative diagnosis of such patients using bronchoscopy with endoluminal biopsy and transthoracic biopsy is not always informative and often the diagnosis can only be established during surgery. The presented case shows that on rare occasions, a giant myofibroblastic tumor of the lung may be encountered in adults, and radical intervention with subsequent rehabilitation can lead to full recovery.

Gallbladder injury in a catatrauma patient: a clinical case

Gallbladder trauma is a rare medical emergency in abdominal surgery because of its anatomic location. Gallbladder injury occurs in only 1.9%-2.1% of cases with abdominal traumas, with an isolated injury being ten times rarer. Despite the different mechanisms of injury, intravesical hypertension is the most important factor contributing to gallbladder rupture. A fall from a height is a rare cause of gallbladder injury, with only a few cases described in the literature. Laparoscopic cholecystectomy is the most common primary treatment. In the present case report, we present the diagnosis and management of a patient with a rare combined trauma. The patient was polytraumatized but had an isolated gallbladder injury in the absence of other abdominal injuries. Modern diagnostic methods, primarily ultrasound, can be critical in determining the best treatment strategy.

Clinical, Morphological Justification and First Experience in the Use of Radiofrequency as Well as Microwave Ablation Treatment Methods of Liver Echinococcosis

Background

The current study considers a new direction of surgical treatment of liver echinococcosis - the use of minimally invasive treatment methods of parasitic cysts.

Methods

After clinical and morphological substantiation of the very possibility of carrying out such procedures, 9 microwave ablations (MWA) and 3 radiofrequency ablations (RFA) of cysts were performed in patients with liver echinococcosis from 2017 to 2021 in the surgical clinic of Botkin Hospital, Moscow, Russia. A comparative analysis of treatment results of patients with echinococcal liver cysts (12 patients who underwent "percutaneous puncture, aspiration, injection and reaspiration" (PAIR) procedure and 12 patients - MWA and RFA) was carried out.

Results

The number of complications according to Clavien-Dindo classification was as follows: 8 after PAIR procedure, 3 after RFA and 3 after MWA. The median hospital length of stay (LOS) after PAIR procedure was 6.46 days versus 4.7 and 4 in the groups of patients who underwent RF and MW ablation, respectively. The frequency of relapses within the first year after PAIR procedure was 25%. The patients who underwent ablation procedures had no relapses of liver echinococcosis during observation.

Conclusion

The presented clinical and morphological substantiation and the experience of using various types of ablation techniques on echinococcal cysts, as well as a comparative analysis with a commonly used PAIR treatment method, demonstrated the safety of RFA and MWA for the patient and efficacy in relation to the hydatid process.

MicroRNAs as Novel Biomarkers for P2Y12 - Inhibitors Resistance Prediction

AIM

The aim of this study is to assess 6 micro-RNAs: miR-126, miR-223, miR-150, miR-29, miR-34, miR-142 as potential biomarkers for P2Y12- inhibitors resistance prediction.

METHODS

Eighty patients with an acute coronary syndrome undergoing percutaneous coronary intervention treated in a multidisciplinary hospital in Moscow with DAPT (either with ticagrelor, n=45, or clopidogrel, n=35) were enrolled. The carriership of 6 clinically relevant polymorphisms for ticagrelor and 17 for clopidogrel was detected. Expression levels of six prospective miRNAs were measured. The activity of CYP3A4 isoenzyme was measured as the ratio of the concentrations of cortisol and 6β-hydroxycortisol.

RESULTS

The polymorphisms of the P2Y12-inhibitors ADME genes that demonstrated statistically significant connection with miRNA expression levels are as follows: P2Y12R (A>G, rs3732759) and miR-29 (p=0.017), miR-34 (p=0.003); CYP2C19*17 (C-806T, rs1224856) and miR-142 (p=0.012); PON1 (Q192R, rs662) and miR-29 (p=0.004), ABCG2 (G>T, rs2231142) and miR-34 (p=0.007). MiRNAs expression levels showed connection with the results of the platelet reactivity assessment by utilizing VerifyNow assay ("Instrumentation laboratory", MA, US). MiR-126 (β coefficient=-0.076, SE=0.032, p=0.021), miR-223 (β coefficient=-0.089, SE=0.041, p=0.032), miR-29 (β coefficient=-0.042, SE=0.018, p=0.026), miR-142 (β coefficient=-0.072, SE=0.026, p=0.008) have the potential to be used as biomarkers and may substitute platelet reactivity testing.

CONCLUSION

This study has revealed new biomarkers for P2Y12-inhibitors resistance testing: miR-29, miR-34, miR-126, miR-142, miR-223.

Selective properties of diffusive couplings and their influence on spatiotemporal chaos

Spatiotemporal chaos in a ring of logistic maps with symmetric diffusive couplings is investigated in dependence on the coupling strength. Spatial spectrum of oscillations is compared with the wave response of a linear spatial filter formed by couplings between maps in the ensemble. Correlation between the spectrum and the filter's amplitude-wave characteristics is considered.

Peculiarities of the transitions to synchronization in coupled systems with amplitude death

The paper presents the results of the study of the sequences of bifurcation leading to the synchronization and amplitude death in a system of two dissipatively coupled self-sustained oscillators with inertial nonlinearity. Two types of synchronizations tongues have been identified. In one of them phase locking regions exist where the synchronization is achieved by the saddle-node bifurcation and regions where the transition to synchronization leads through Neimark-Sacker bifurcation. In the second type of the tongues there are only phase locking regions. It has been shown that for a weak non-identity of the system parameters, the first type tongues merge together. The transition between the synchronization tongues can occur without bifurcations, i.e., transition between the synchronized regimes with different periods of oscillations can occur gradually.

Phase multistability and phase synchronization in an array of locally coupled period-doubling oscillators

We consider phase multistability and phase synchronization phenomena in a chain of period-doubling oscillators. The synchronization in arrays of diffusively coupled self-sustained oscillators manifests itself as rotating wave regimes, which are characterized by equal amplitudes and phases in every site which are shifted by a constant value. The value of the phase shift is preserved while the shape of motion becomes more complex through a period-doubling cascade. The number of coexisting attractors increases drastically after the transition from period-one to period-two oscillations and then after every following period-doubling bifurcation. In the chaotic region, we observe a number of phase-synchronized modes with instantaneous phases locked in different values. The loss of phase synchronization with decreasing coupling is accompanied by intermittency between several synchronous regimes.

Synchronization of stochastic oscillations due to long-range diffusion

We investigate the effect of long-range diffusive mixing on stochastic processes taking place on low-dimensional catalytic supports. As a working example, the cyclic lattice Lotka-Volterra (LLV) model is used which is conservative at the mean-field level and demonstrates fractal patterns and local oscillations when realized on low-dimensional lattice supports. We show that the local oscillations are synchronized when a weak, long-range, diffusive process is added to LLV and global oscillations of limit cycle type emerge. This phenomenon is demonstrated as a nonequilibrium phase transition and takes place when the mixing-to-reaction rate p (order parameter) is above a critical point p_{c} . The value of the critical point is shown to depend on the kinetic parameters. The global oscillations in this case emerge as a result of phase synchronization between local oscillations on sublattices.

Quantitative analysis of chaotic synchronization by means of coherence

We use an index of chaotic synchronization based on the averaged coherence function for the quantitative analysis of the process of the complete synchronization loss in unidirectionally coupled oscillators and maps. We demonstrate that this value manifests different stages of the synchronization breaking. It is invariant to time delay and insensitive to small noise and distortions, which can influence the accessible signals at measurements. Peculiarities of the synchronization destruction in maps and oscillators are investigated.

Information theoretic approach to quantify complete and phase synchronization of chaos

Based on an information theory approach we suggest a quantitative characteristic for evaluating the degree of chaotic synchronization. The proposed characteristic is tested for the cases of complete and phase synchronization of chaos. It is shown that this characteristic is stable with respect to the influence of small noise and nonlinear signal distortion.

Multistability formation and synchronization loss in coupled Hénon maps: two sides of the single bifurcational mechanism

We investigate phenomena of multistability and complete chaos synchronization in coupled Hénon maps, which is an invertible system. Multiparametric analysis of a selected family of periodic orbits for coupled Henon maps shows that a single bifurcational mechanism describes both a loss of chaos synchronization and multistability formation. The process of bubbling transition and riddle basins, and the multistability formation in invertible systems are described in detail.