Suicidal Behaviors Among Ukrainian College Students: the Role of Substance Use,Religion, and Depression

Early adulthood is a critical life period associated with increased suicide risk. The present study used a sample of students from ten Ukrainian public universities (N = 1005). Participants were 17 to 24 years of age (M = 19.19, SD = 1.99). The prevalence of lifetime suicidal ideation was 26.13% and 5.45% of participants reported a lifetime suicide attempt. Participants were more likely to report higher lifetime suicidal ideation if they had higher rates of alcohol and marijuana use, have met a clinical cutoff point for depression and were older, females, and not affiliated with any religion. The lifetime suicide attempt was associated with clinical levels of depression, increased marijuana use, and non-religious affiliation. These results suggest that mental health, alcohol and cannabis use can increase the risk of suicidality while religious affiliation might be an important protective mechanism for Ukrainian young adults at risk for suicidal behaviors.

     

Accordion waves in Myxococcus xanthus

Myxococcus xanthus are Gram-negative bacteria that glide on solid surfaces, periodically reversing their direction of movement. When starved, M. xanthus cells organize their movements into waves of cell density that sweep over the colony surface. These waves are unique: Although they appear to interpenetrate, they actually reflect off one another when they collide, so that each wave crest oscillates back and forth with no net displacement. Because the waves reflect the coordinated back and forth oscillations of the individual bacteria, we call them "accordion" waves. The spatial oscillations of individuals are a manifestation of an internal biochemical oscillator, probably involving the Frz chemosensory system. These internal "clocks," each of which is quite variable, are synchronized by collisions between individual cells using a contact-mediated signal-transduction system. The result of collision signaling is that the collective spatial behavior is much less variable than the individual oscillators. In this work, we present experimental observations in which individual cells marked with GFP can be followed in groups of unlabeled cells in monolayer cultures. These data, together with an agent-based computational model demonstrate that the only properties required to explain the ripple patterns are an asymmetric biochemical limit cycle that controls direction reversals and asymmetric contact-induced signaling between cells: Head-to-head signaling is stronger than head-to-tail signaling. Together, the experimental and computational data provide new insights into how populations of interacting oscillators can synchronize and organize spatially to produce morphogenetic patterns that may have parallels in higher organisms.     

Transfer of 4‐hydroxynonenal from parasitized to non‐parasitized erythrocytes in rosettes. Proposed role in severe malaria anemia

Severe anaemia is a life‐threatening complication of falciparum malaria associated with loss of predominantly non‐parasitized red blood cells (npRBCs). This poorly elucidated process might be influenced by (i) rosettes, i.e. npRBCs cytoadherent to haemozoin‐containing parasitized RBCs (pRBCs) and (ii) generation in pRBCs of 4‐hydroxynonenal (4‐HNE) through haemozoin‐catalysed lipid peroxidation. We explored whether close proximity in rosettes may facilitate 4‐HNE transfer to npRBCs, which is likely to enhance their phagocytosis and contribute to malaria anaemia. Fluorescence microscopy and flow cytometry data indicated 4‐HNE transfer to npRBCs in rosettes. Rosettes were formed by 64·8 ± 1·8% varO‐expressing pRBCs, and 8·7 ± 1·1% npRBCs were positive for 4‐HNE‐protein‐conjugates, while low‐rosetting parasites generated only 2·4 ± 1·1% 4‐HNE‐conjugate‐positive npRBCs. 4‐HNE transfer decreased after blocking rosetting by monoclonal antibodies. A positive linear relationship between rosette frequency and 4‐HNE‐conjugates in npRBCs was found in 40 malaria patients, a first indication for a role of rosetting in npRBCs modifications in vivo. Children with severe malaria anaemia had significantly higher percentages of 4‐HNE‐conjugate‐positive npRBCs compared to children with uncomplicated malaria. In conclusion, 4‐HNE transfer from pRBCs to npRBCs in rosettes is suggested to play a role in the phagocytic removal of large numbers of npRBCs, the hallmark of severe malaria anaemia.     

Prenatal Diagnosis of Left Pulmonary Artery-to-Pulmonary Vein Fistula and Its Successful Surgical Repair in a Neonate

Pulmonary arteriovenous fistula is a rare disease. To the best of our knowledge, prenatal diagnosis of a fistula between the left pulmonary artery and the left pulmonary vein has not been described in the medical literature. We report a case of the prenatal diagnosis of a left pulmonary artery-to-pulmonary vein fistula, followed by successful neonatal surgical repair.     

Search for Compounds with Hypoglycemic Activity in the Series of 1-[2-(1H-Tetrazol-5-yl)-R1-phenyl]-3-R2-phenyl(ethyl)ureas and R1-Tetrazolo[1,5-c]quinazolin-5(6H)-ones

Methods of 1-[2-(1H-tetrazol-5-yl)-R¹-phenyl]-3-R²-phenyl(ethyl)ureas and R¹-tetrazolo[1,5-c]quinazolin-5(6H)-ones synthesis were designed. IR, LC-MS, ¹H NMR, and elemental analysis data evaluated the structure and purity of the obtained compounds. Different products, depending on the reaction conditions, were distinguished and discussed. The preliminary hypoglycemic activity of 36 synthesized compounds was revealed. Docking studies to 11β-hydroxysteroid dehydrogenase 1, γ-peroxisome proliferator-activated receptor, and dipeptidyl peptidase-4 were conducted. Eight of these substances were further tested on glucocorticoid-induced insulin resistance models, namely glucose tolerance, oral rapid insulin, and adrenalin tests. One of the most active compounds turned out to be tetrazolo[1,5-c]quinazolin-5(6H)-one 3.1, exceeding the reference drugs Metformin (50 and 200 mg/kg) and Gliclazide (50 mg/kg).     

High Densification of Tungsten via Hot Pressing at 1300 °C in Carbon Presence

A reactive sintering technique with a small addition of carbon (up to 1.9 wt.%) has been used for tungsten powder consolidation. The process allowed procurement of the nonporous and fully densified material at 1300 °C and 30 MPa in 12 min. The SEM and EDX analysis showed that the milling of 5 μm tungsten powder with 0.6, 1.3, and 1.9 wt.% of carbon in a planetary mill led to the formation of the nanostructured mix, which appears to be W-C nanopowder surrounding tungsten grains. X-Ray Diffractometry data indicated tungsten hemicarbide (W₂C) nucleation during the hot pressing of the milled powders. The exothermic reaction 2W + C → W₂C occurs during the sintering process and promotes charge densification. The Vickers hardness and indentation toughness of W-1.3 wt.%C composition reached 5.7 GPa and 12.6 MPa∙m^1/2, respectively. High toughness and high material densification allow proposing the W-WC₂ for use as a plasma-facing material in fusion applications.     

Doxorubicin pharmacokinetics in lymphoma patients treated with doxorubicin-loaded eythrocytes

Doxorubicin-loaded erythrocytes (DLE) were administrated to 15 lymphoma patients. Antibiotic peak concentration in blood decreased by 55%, doxorubicin circulated several times longer, and the area under the concentration-time curve increased 5 times if compared with standard doxorubicin administration. The DLE was well tolerated by patients.