Identification and Characterization of a New Tubulin-Binding

We studied the mechanism of action of 3,5-dibromo-4-(3,4-dimethoxyphenyl)-1H-pyrrole-2-carboxylic acid ethyl ester (JG-03-14) and found that it is a potent microtubule depolymerizer. JG-03-14 caused a dose-dependent loss of cellular microtubules, formation of aberrant mitotic spindles, accumulation of cells in the G2/M phase of the cell cycle, and Bcl-2 phosphorylation. These events culminated in the initiation of apoptosis, as evidenced by the caspase 3-dependent cleavage of poly(ADP-ribose) polymerase (PARP). JG-03-14 has antiproliferative activity against a wide range of cancer cell lines, with an average IC50 value of 62 nM, and it is a poor substrate for transport by P-glycoprotein. JG-03-14 inhibited the polymerization of purified tubulin in vitro, consistent with a direct interaction between the compound and tubulin. JG-03-14 potently inhibited the binding of [3H]colchicine to tubulin, suggesting that it bound to tubulin at a site overlapping the colchicine site. JG-03-14 had antitumor effects in the PC3 xenograft model, in which it caused greater than 50% reduction in tumor burden after 14 days of treatment. Molecular modeling studies indicated that the dimethoxyphenyl group of JG-03-14 occupies a space similar to that of the trimethoxyphenyl group of colchicine. However, the 2,3,5-trisubstituted pyrrole group, which is connected to the dimethoxyphenyl moiety, interacted with both α and β tubulin in space not shared with colchicine, suggesting significant differences compared with colchicine in the mechanism of binding to tubulin. Our results suggest that this tetransubstituted pyrrole represents a new, biologically active chemotype for the colchicine site on tubulin

Kind granddaughters of angry grandmothers: The effect of domestication on vocalization in cross-bred silver foxes

a b s t r a c t The genetic basis of the effects of domestication has previously been examined in relation to morphological, physiological and behavioural traits, but not for vocalizations. According t

Electrospray droplet manipulation via reagent vapor introduction

A technique was developed to manipulate electrospray generated charged droplets via reactions with volatile reagents introduced into the interface of a QqTOF tandem mass spectrometer. This near atmospheric pressure region just outside and between the curtain and orifice plates is where the molecule/droplet interaction takes place on the sub-millisecond time-scale of the droplet evaporation. Work was devoted to exploring, developing, and optimizing this approach for a variety of applications. It was found that the introduction of volatile acids into the mass spectrometer interface can be used to remove unwanted metal counter-ions. Weak acids were best to use in the negative polarity and strong acids were best to remove metal counter-ions in the positive polarity. When proteins were ionized in the positive polarity and various acids of increasing strength were introduced, a much higher charge state distribution and average charge state were observed. Similarly, introducing bases of increasing strength in the negative polarity resulted in the observation of much higher, more negative charge states. In both cases, this was correlated to protein unfolding. Similarly, it was found that introducing acidic vapors in the negative polarity and basic vapors in the positive polarity can shift the distribution to much lower charge states, suggesting that the protein was now in a more folded conformation. To test the theory that the observed charge state distributions can be correlated to various protein conformations, hydrogen/deuterium exchange was performed using the vapor introduction technique. Deuterated acids and bases were introduced to shift the charge state distributions while at the same time performing hydrogen/deuterium exchange on the newly formed conformations. A greater degree of deuterium uptake is observed for a more unfolded conformation. Finally, various mixtures were studied to see if the vapor introduction technique can be utilized as a tool to simplify spectral analysis and eliminate common matrix effects. It was found that the introduction of volatile acids and bases effectively changes the droplet pH and will affect which components of a mixture are observed over others. The introduction of various organic solvents and the use of other carrier gases, like carbon dioxide, can also be used to affect partitioning within the droplet. In general, this is a very simple and flexible technique with many variables that can be altered to manipulate electrospray generated droplets

GEMORRAGIK KASALLIKLARGA CHALINGAN CHUQUR ERTA TUG'ILGAN CHAQALOQLARDA GEMOSTAZ TIZIMINI BOSHQARUVCHI GENLARNING POLIMORFIZMINING XUSUSIYATLARI

Currently, there is a need for a comprehensive assessment of the state of the hemostasis system in deeply premature newborns, including not only an assessment of the state of the vascular wall, platelet and plasma links of hemostasis, as well as the identification of features of polymorphism of genes controlling hemostasis. The identification of these features will help in predicting the development of hemorrhagic disorders in deeply premature newborns, which will make it possible to personalize the management tactics of this category of patients and reduce the rates of disability and infant mortality. In order to identify variants of polymorphism of genes of the hemostasis system in deeply premature newborns, a genetic examination of 99 children with a gestation period of up to 32 weeks was performed. With the definition of gene polymorphism: F2, F7, F13A1, FGB, ITGA2-a2, ITGB3-b3, PAI1. The study established combined variants of hemostasis gene polymorphism in children with hemorrhagic disorders, which can serve as a predictor of the formation of disorders in the hemostasis system.В настоящее время существует необходимость в комплексной оценке состояния системы гемостаза у глубоко недоношенных новорожденных, включающий не только оценку состояния сосудистой стенки, тромбоцитарного и плазменного звеньев гемостаза, а также выявление особенностей полиморфизма генов, контролирующих гемостаз. Выявление данных особенностей поможет в прогнозировании развития геморрагических нарушений у глубоко недоношенных новорожденных, что позволит персонифицировать тактику ведения данной категории пациентов и снизить показатели инвалидизации и младенческой смертности. С целью выявления вариантов полиморфизма генов системы гемостаза у глубоко недоношенных новорожденных, выполнено генетическое обследование 99 детей со сроком гестации до 32 недель. С определением полиморфизма генов: F2, F7, F13A1, FGB, ITGA2-a2, ITGB3-b3, PAI1. В ходе исследования установлены сочетанные варианты полиморфизма генов гемостаза у детей с геморрагическими нарушениями, которые могут служить в качестве предиктора формирования нарушений в системе гемостаза.Hozirgi vaqtda chuqur erta tug'ilgan chaqaloqlarda gemostaz tizimining holatini har tomonlama baholash, shu jumladan nafaqat qon tomir devorining holatini, gemostazning trombotsitlar va plazma birliklarini baholash, balki gemostazni boshqaruvchi genlarning polimorfizmining xususiyatlarini aniqlash kerak. Ushbu xususiyatlarni aniqlash chuqur erta tug'ilgan chaqaloqlarda gemorragik kasalliklarning rivojlanishini bashorat qilishga yordam beradi, bu esa ushbu toifadagi bemorlarni boshqarish taktikasini shaxsiylashtirishga va nogironlik va bolalar o'limini kamaytirishga imkon beradi. Chuqur erta tug'ilgan chaqaloqlarda gemostaz tizimining gen polimorfizmining variantlarini aniqlash uchun homiladorlik davri 32 haftagacha bo'lgan 99 bolaning genetik tekshiruvi o'tkazildi. Gen polimorfizmining ta'rifi bilan: F2, F7, F13A1, FGB, ITGA2-a2, ITGB3-b3, PAI1. Tadqiqot davomida gemorragik kasalliklarga chalingan bolalarda gemostaz genlarining polimorfizmining birlashtirilgan variantlari aniqlandi, ular gemostaz tizimida buzilishlar shakllanishining bashoratchisi bo'lib xizmat qilishi mumkin

Cytoskeleton Markers in the Spinal Cord and Mechanoreceptors of Thick-Toed Geckos after Prolonged Space Flights

Spaceflight may cause hypogravitational motor syndrome (HMS). However, the role of the nervous system in the formation of HMS remains poorly understood. The aim of this study was to estimate the effects of space flights on the cytoskeleton of the neuronal and glial cells in the spinal cord and mechanoreceptors in the toes of thick-toed geckos (Chondrodactylus turneri GRAY, 1864). Thick-toed geckos are able to maintain attachment and natural locomotion in weightlessness. Different types of mechanoreceptors have been described in the toes of geckos. After flight, neurofilament 200 immunoreactivity in mechanoreceptors was lower than in control. In some motor neurons of flight geckos, nonspecific pathomorphological changes were observed, but they were also detected in the control. No signs of gliosis were detected after spaceflight. Cytoskeleton markers adequately reflect changes in the cells of the nervous system. We suggest that geckos’ adhesion is controlled by the nervous system. Our study revealed no significant disturbances in the morphology of the spinal cord after the prolonged space flight, supporting the hypothesis that geckos compensate the alterations, characteristic for other mammals in weightlessness, by tactile stimulation

Affecting Protein Charge State Distributions in Nano-Electrospray Ionization via In-Spray Solution Mixing Using Theta Capillaries

Borosilicate theta glass capillaries pulled to serve as nanoelectrospray ionization emitters are used for short time-scale mixing of protein and acid solutions during the electrospray process to alter protein charge state distributions (CSDs) without modifying the sample solution. The extent of protein CSD shifting/denaturing can be tailored by acid identity and concentration. The observed CSD(s) are protein dependent, and the short mixing time-scale enables the study of short-lived unfolding intermediates and higher charge states of noncovalent protein complexes, including those of holomyoglobin. Additionally, the theta tips provide a simple and inexpensive method for mixing nonvolatile reagents such as supercharging agents, which cannot be used with previously developed vapor leak-in techniques, with protein solutions during the electrospray process