Differential Calcium Signaling by Cone Specific Guanylate Cyclase-Activating Proteins from the Zebrafish Retina

Zebrafish express in their retina a higher number of guanylate cyclase-activating proteins (zGCAPs) than mammalians pointing to more complex guanylate cyclase signaling systems. All six zGCAP isoforms show distinct and partial overlapping expression profiles in rods and cones. We determined critical Ca2+-dependent parameters of their functional properties using purified zGCAPs after heterologous expression in E.coli. Isoforms 1–4 were strong, 5 and 7 were weak activators of membrane bound guanylate cyclase. They further displayed different Ca2+-sensitivities of guanylate cyclase activation, which is half maximal either at a free Ca2+ around 30 nM (zGCAP1, 2 and 3) or around 400 nM (zGCAP4, 5 and 7). Zebrafish GCAP isoforms showed also differences in their Ca2+/Mg2+-dependent conformational changes and in the Ca2+-dependent monomer-dimer equilibrium. Direct Ca2+-binding revealed that all zGCAPs bound at least three Ca2+. The corresponding apparent affinity constants reflect binding of Ca2+ with high (≤100 nM), medium (0.1–5 µM) and/or low (≥5 µM) affinity, but were unique for each zGCAP isoform. Our data indicate a Ca2+-sensor system in zebrafish rod and cone cells supporting a Ca2+-relay model of differential zGCAP operation in these cells

Effectiveness of intravenous isoniazid and ethambutol administration in patients with tuberculosis meningoencephalitis and HIV infection

Effectiveness of intravenous isoniazid and ethambutol administration in patients with tuberculosis meningoencephalitis and HIV infection / Dmytro Butov, Yurii Feshchenko, Mykhailo Kuzhko, Mykola Gumenuik, Kateryna Yurko, Alina Grygorova, Anton Tkachenko, Natalia Nekrasova, Tetiana Tlustova, Vasyl Kikinchuk, Alexandr Peshenko, Tetiana Butova // Tuberculosis and Respiratory Diseases. – 2019. – № 82. – Р. 1-8. – DOI: https://doi.org/10.4046/trd.2019.0021Метою даного дослідження було вивчення ефективності внутрішньовенного введення ізоніазиду (І) та етамбутолу (Е) у пацієнтів з лікарсько-чутливим туберкульозом легень (ТЛ) з позитивним результатом мокротиння, туберкульозним менінгоенцефалітом (ТМ) та вірусом імунодефіциту людини (ВІЛ) у інтенсивній фазі лікеування. При ТЛ/ТМ з ВІЛ внутрішньовенне лікування І та Е було більш ефективним, ніж пероральне лікування І та Е, через 2 місяці інтенсивного лікування в конверсії мокротиння, а також у клінічному поліпшенні, що супроводжується значно вищими середніми концентраціями у сироватці. Крім того, рівень смертності був нижчим при внутрішньовенному лікуванні І та Е порівняно з пероральним лікуванням.The aim of this study was to investigate the effectiveness of intravenous isoniazid (H) and ethambutol (E) administered in patients with new sputum positive drug-susceptible pulmonary tuberculosis (TB) with tuberculous meningoencephalitis (TM) and human immunodeficiency virus (HIV) co-infection in the intensive phase of treatment. In TB/TM with HIV, the intravenous H and E treatment was more effective than oral H and E treatment at 2 months of intensive treatment in sputum conversion as well as in clinical improvement, accompanied by significantly higher mean serum concentrations. In addition, the mortality rate was lower in intravenous H and E treatment compared to oral treatment.Целью данного исследования было изучение эффективности внутривенного введения изониазида (И) и этамбутола (Э) у пациентов с лекарственно-чувствительным туберкулезом легких (ТЛ) с положительным результатом мокроты, туберкулезным менингоэнцефалитом (ТМ) и вирусом иммунодефицита человека (ВИЧ) в интенсивной фазе лечения. При ТЛ/ТМ с ВИЧ внутривенное лечение И и Э было более эффективным, чем пероральное лечение И и Э, через 2 месяца интенсивного лечения в конверсии мокроты, а также в клиническом улучшении, сопровождаемом значительно более высокими средними концентрациями в сыворотке. Кроме того, уровень смертности был ниже при внутривенном лечении И и Э по сравнению с пероральным лечением

Peroxiredoxin 6 in human brain: molecular forms, cellular distribution and association with Alzheimer’s disease pathology

Peroxiredoxin 6 is an antioxidant enzyme and is the 1-cys member of the peroxiredoxin family. Using two-dimensional electrophoresis and Western blotting, we have shown for the first time that, in human control and brain tissue of patient’s with Alzheimer’s disease (AD), this enzyme exists as three major and five minor forms with pIs from 5.3 to 6.1. Using specific cellular markers, we have shown that peroxiredoxin 6 is present in astrocytes with very low levels in neurons, but not detectable in microglia or oligodendrocytes. In control brains, there was a very low level of peroxiredoxin 6 staining in astrocytes that was confined to a “halo” around the nucleus. In AD, there were marked increases in the number and staining intensity of peroxiredoxin 6 positive astrocytes in both gray and white matter in the midfrontal cortex, cingulate, hippocampus and amygdala. Confocal microscopy using antibodies to Aβ peptide, tau and peroxiredoxin 6 showed that peroxiredoxin 6 positive astrocytes are closely involved with diffuse plaques and to a lesser extent with neuritic plaques, suggesting that plaques are producing reactive oxygen species. There appeared to be little astrocytic response to tau containing neurons. Although peroxiredoxin 6 positive astrocytes were seen to make multiple contacts with tau positive neurons, there was no intraneuronal colocalization. In brain tissue of patients with AD, many blood vessels exhibited peroxiredoxin 6 staining that appeared to be due to the astrocytic foot processes. These results suggest that oxidative stress conditions exist in AD and that peroxiredoxin 6 is an important antioxidant enzyme in human brain defenses

Night Vision Restored in Days After Decades of Congenital Blindness

Signaling of vision to the brain starts with the retinal phototransduction cascade which converts visible light from the environment into chemical changes. Vision impairment results when mutations inactivate proteins of the phototransduction cascade. A severe monogenically inherited blindness, Leber congenital amaurosis (LCA), is caused by mutations in the GUCY2D gene, leading to a molecular defect in the production of cyclic GMP, the second messenger of phototransduction. We studied two patients with GUCY2D-LCA who were undergoing gene augmentation therapy. Both patients had large deficits in rod photoreceptor-based night vision before intervention. Within days of therapy, rod vision in both patients changed dramatically; improvements in visual function and functional vision in these hyper-responding patients reached more than 3 log10 units (1000-fold), nearing healthy rod vision. Quick activation of the complex molecular pathways from retinal photoreceptor to visual cortex and behavior is thus possible in patients even after being disabled and dormant for decades

навчальний посібник

Судова медицина та психіатрія : навч. посіб. / Кікінчук В. В., Лозова С. М., Гусєва В. О. та ін.; МВС України, Харків. нац. ун-т внутр. справ. – Харків, 2019. – 184 с. – ISBN 978-966-610-240-2.Навчальний посібник підготовлений на основі навчальної програми «Судова медицина та психіатрія», затвердженої для Харківського національного університету внутрішніх справ. Викладені основні теоретичні положення судової медицини та судової психіатрії, а також практичні рекомендації з використання спеціальних медичних і психіатричних знань під час досудового розслідування розраховані на підготовку фахівців для підрозділів Національної поліції України. Призначений для курсантів, студентів, слухачів і викладачів закладів вищої освіти системи МВС України, а також практичних працівників органів кримінальної юстиції.The basic theoretical provisions of forensic medicine and forensic psychiatry, as well as practical recommendations for the use of specialized medical and psychiatric knowledge in the pre-trial investigation are designed to train specialists for the units of the National Police of Ukraine.Изложены основные теоретические положения судебной медицины и судебной психиатрии, а также практические рекомендации по использованию специальных медицинских и психиатрических знаний во время досудебного расследования. Учебное пособие рассчитано на подготовку специалистов для подразделений Национальной полиции Украины

СУДОВО-МЕДИЧНА ОЦІНКА ТРАВМ ШИЙНОГО ВІДДІЛУ ХРЕБТА З УРАХУВАННЯМ ЗМІН ЦЕНТРАЛЬНОЇ ГЕМОДИНАМТКИ

The article analyzes the up-to-date state and problematic issues of forensic medical diagnosis of cervical spine injuries. It establishes that there are cases when forensic medical experts underestimate the outcomes and consequences of this trauma. It studies the state of the central hemodynamics of the injured with cervical spine traumas. At the same time 107 injured were divided into two groups: with clear and moderate manifestations. The research applied an objective and modern method of Doppler echocardiography. The conducted research has demonstrated significant changes in extraand intracerebral blood flow. The results of the comparative analysis show that forensic medical assessment of cervical spine traumas should take into account the results of Doppler echocardiography. Among these results the most informative are functional changes of the cerebral and spinal arteries. The manifestation of these deviations is determined, primarily, by the severity and time of injuries. The article determines the ways of improving forensic medical examinations of the injured with cervical spine traumas. It demonstrates the criteria significance of changes in bloodflow of cerebral and cervical arteries of the injured while establishing the severity of injuries.Досліджено стан центральної гемодинаміки в постраждалих із травмами шийного відділу хребта. За результатами порівняльного аналізу доведено, що судово-медична оцінка травм шийного відділу хребта має враховувати допплерографічні показники, серед яких найбільш інформативними є функціональні зміни загальної мозкової й хребцевої артерій

Structural Insights for Activation of Retinal Guanylate Cyclase by GCAP1

Guanylyl cyclase activating protein 1 (GCAP1), a member of the neuronal calcium sensor (NCS) subclass of the calmodulin superfamily, confers Ca(2+)-sensitive activation of retinal guanylyl cyclase 1 (RetGC1) upon light activation of photoreceptor cells. Here we present NMR assignments and functional analysis to probe Ca(2+)-dependent structural changes in GCAP1 that control activation of RetGC. NMR assignments were obtained for both the Ca(2+)-saturated inhibitory state of GCAP1 versus a GCAP1 mutant (D144N/D148G, called EF4mut), which lacks Ca(2+) binding in EF-hand 4 and models the Ca(2+)-free/Mg(2+)-bound activator state of GCAP1. NMR chemical shifts of backbone resonances for Ca(2+)-saturated wild type GCAP1 are overall similar to those of EF4mut, suggesting a similar main chain structure for assigned residues in both the Ca(2+)-free activator and Ca(2+)-bound inhibitor states. This contrasts with large Ca(2+)-induced chemical shift differences and hence dramatic structural changes seen for other NCS proteins including recoverin and NCS-1. The largest chemical shift differences between GCAP1 and EF4mut are seen for residues in EF4 (S141, K142, V145, N146, G147, G149, E150, L153, E154, M157, E158, Q161, L166), but mutagenesis of EF4 residues (F140A, K142D, L153R, L166R) had little effect on RetGC1 activation. A few GCAP1 residues in EF-hand 1 (K23, T27, G32) also show large chemical shift differences, and two of the mutations (K23D and G32N) each decrease the activation of RetGC, consistent with a functional conformational change in EF1. GCAP1 residues at the domain interface (V77, A78, L82) have NMR resonances that are exchange broadened, suggesting these residues may be conformationally dynamic, consistent with previous studies showing these residues are in a region essential for activating RetGC1