Dynamic Resonance Effects in the Statistical Distributions of Asteroids and Comets

Some principles in the distribution of Centaurs and the "Scattered Disk" objects, as well as the Kuiper belt objects for its semi-major axes, eccentricities and inclinations of the orbits have been investigated. It has been established, that more than a half from them move on the resonant orbits and that is what has been predicted earlier. The divergence of the maximum in the observable distribution of the objects of the Kuiper belt for the semi-major axes with an exact orbital resonance has been interpreted.Comment: 7 pages, 5 figures, 1 table. International Conference "100 years since Tunguska phenomenon: Past, present and future", (June 26-28, 2008. Russia, Moscow), International Conference "Modern problems of astronomy" (August 12-18, 2007, Ukraine, Odessa

Protein complex directs hemoglobin-to-hemozoin formation in Plasmodium falciparum

Malaria parasites use hemoglobin (Hb) as a major nutrient source in the intraerythrocytic stage, during which heme is converted to hemozoin (Hz). The formation of Hz is essential for parasite survival, but to date, the underlying mechanisms of Hb degradation and Hz formation are poorly understood. We report the presence of a ∼200-kDa protein complex in the food vacuole that is required for Hb degradation and Hz formation. This complex contains several parasite proteins, including falcipain 2/2', plasmepsin II, plasmepsin IV, histo aspartic protease, and heme detoxification protein. The association of these proteins is evident from coimmunoprecipitation followed by mass spectrometry, coelution from a gel filtration column, cosedimentation on a glycerol gradient, and in vitro protein interaction analyses. To functionally characterize this complex, we developed an in vitro assay using two of the proteins present in the complex. Our results show that falcipain 2 and heme detoxification protein associate with each other to efficiently convert Hb to Hz. We also used this in vitro assay to elucidate the modes of action of chloroquine and artemisinin. Our results reveal that both chloroquine and artemisinin act during the heme polymerization step, and chloroquine also acts at the Hb degradation step. These results may have important implications in the development of previously undefined antimalarials

Tocilizumab induced immunosuppression in a case of adult-onset still’s disease: are these newer biologics double edged sword?

Adult-onset still’s disease (AOSD) is a rare multisystemic inflammatory disorder of unknown etiology characterised by high spiking fever, evanescent skin rash, arthralgias, arthritis, neutrophilic leucocytosis. Initial treatment strategy includes use of hands-on drugs like non-steroidal anti-inflammatory drugs, low dose corticosteroids, conventional DMARDs. But as the disease progresses to severe form, targeted and biologic DMARDs could be the option for management. Interleukin-6 being one among the many cytokines involved in the pathogenesis of AOSD, has made itself a target for the treatment of refractory cases. Tocilizumab, a recombinant humanized anti IL-6 monoclonal antibody, is one such biologic drug available in the market that has proven its therapeutic efficacy in several clinical trials. We are presenting a case of 37-year-old female patient, known case of AOSD for 4 years. Patient was initially maintained on low dose corticosteroid and conventional DMARD like hydroxychloroquine and methotrexate. Flare ups of the disease warranted the use of tocilizumab and tofacitinib in this patient. After clinical as well as pathological improvement with tocilizumab 2 years before, signs of immunosuppression were observed when tocilizumab was reintroduced for the treatment. Patient suffered from acute pyelonephritis, septicemia, shock, oropharyngeal candidiasis and bronchitis which could be owned to immunosuppressive action of tocilizumab. One can reduce the chances of infection and other adverse effects by careful periodic monitoring of various laboratory parameters like total W.B.C., total platelet count and liver enzymes. Cautious selection of the patient is needed for the treatment with newer biologic agents

Highly efficient bienzyme functionalized nanocomposite-based microfluidics biosensor platform for biomedical application

This report describes the fabrication of a novel microfluidics nanobiochip based on a composite comprising of nickel oxide nanoparticles (nNiO) and multiwalled carbon nanotubes (MWCNTs), as well as the chip's use in a biomedical application. This nanocomposite was integrated with polydimethylsiloxane (PDMS) microchannels, which were constructed using the photolithographic technique. A structural and morphological characterization of the fabricated microfluidics chip, which was functionalized with a bienzyme containing cholesterol oxidase (ChOx) and cholesterol esterase (ChEt), was accomplished using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy. The XPS studies revealed that 9.3% of the carboxyl (COOH) groups present in the nNiO-MWCNT composite are used to form amide bonds with the NH 2 groups of the bienzyme. The response studies on this nanobiochip reveal good reproducibility and selectivity, and a high sensitivity of 2.2â.mA/mM/cm 2. This integrated microfluidics biochip provides a promising low-cost platform for the rapid detection of biomolecules using minute samples

The formation of Uranus and Neptune among Jupiter and Saturn

The outer giant planets, Uranus and Neptune, pose a challenge to theories of planet formation. They exist in a region of the Solar System where long dynamical timescales and a low primordial density of material would have conspired to make the formation of such large bodies ($\sim$ 15 and 17 times as massive as the Earth, respectively) very difficult. Previously, we proposed a model which addresses this problem: Instead of forming in the trans-Saturnian region, Uranus and Neptune underwent most of their growth among proto-Jupiter and -Saturn, were scattered outward when Jupiter acquired its massive gas envelope, and subsequently evolved toward their present orbits. We present the results of additional numerical simulations, which further demonstrate that the model readily produces analogues to our Solar System for a wide range of initial conditions. We also find that this mechanism may partly account for the high orbital inclinations observed in the Kuiper belt.Comment: Submitted to AJ; 38 pages, 16 figure