Capsular Warning Syndrome - A Case Series and Discussion on Management Dilemmas.

BACKGROUND: The term 'Capsular warning syndrome (CWS)' refers to recurrent, stereotypical transient ischemic attacks, either motor, sensory or both, without cortical symptoms or signs. Of these patients, 42-71% go on to develop infarcts. There are no defined treatment guidelines for this lesser known entity. METHODS: We studied 9 patients who presented over last 2 years to our hospital with recurrent and stereotypical transient ischemic attacks suggestive of capsular warning syndrome. Their clinical characteristics, neuroimaging findings, relevant etiological investigations, management and outcomes were studied. RESULTS: Seven out of 9 patients were under 40 years of age. The commonest presentation in our series was a pure motor syndrome. The duration of neurologic deficits ranged from 5 minutes to 20 minutes with complete recovery in between episodes. Three patients had concordant abnormalities on CT brain angiography. Five out of 9 patients received IV thrombolysis with t-PA. One patient worsened neurologically post thrombolysis, whilst the others improved clinically. DISCUSSION: Despite multiple hypotheses, the pathogenesis and management of CWS has not been established clearly. Due to fluctuating neurological symptoms with complete recovery in between the episodes, there is a dilemma concerning treatment of such patients with intravenous thrombolysis. However, intravenous thrombolysis appears to be safe in CWS as in acute ischemic stroke, followed by treatment with antiplatelet agents.

Realization of High Capacity and Cycling Stability in Pb-Free A2 CuBr4 (A=CH3 NH3 /Cs, 2 D/3 D) Perovskite-Based Li-Ion Battery Anodes.

Lead-free hybrid and inorganic perovskites (A2 CuBr4 ; A=CH3 NH3 or Cs, 2 D or3 D) are synthesized by a room-temperature solid-state reaction route and examined as anode materials in Li-ion batteries. A remarkably high reversible capacity of 630 mAh g-1 is realized in the 2 D hybrid perovskite at 100 mA g-1 at the end of 140 cycles. A full cell with this anode is also tested and shows impressive cycling stability. A good reversible capacity of 420 mAh g-1 with excellent stability tested up to 1400 cycles is also obtained for the 3 D perovskites. Pb-free hybrid/inorganic halide perovskites can thus be used as viable anode materials for battery applications.

Synthesis of cerium and nickel doped titanium nanofibers for hydrolysis of sodium borohydride.

A recyclable titanium nanofibers, doped with cerium and nickel doped was successfully synthesized by using sol-gel and electrospinning method for hydrogen generation from alkali free hydrolysis of NaBH4. The resultant nanocomposite was characterized to find out the structural and physical-chemical properties by a series of analytical techniques such as FT-IR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), SEM (scanning electron microscope), EDX (energy-dispersive X-ray spectroscopy),N2 adsorption-desorption and BET (Brunauer-Emmett-Teller), etc. The results revealed that cerium and nickel nanoparticles were homogeneously distributed on the surface of the TiO2 nanofibers due to having similar oxidation state and atomic radium of TiO2nanofibers with CeO2 and NiO for the effective immobilization of metal ions. The NiO doped catalyst showed superior catalytic performance towards the hydrolysis reaction of NaBH4 at room temperature. These catalysts have ability to produce 305 mL of H2 within the time of 160 min at room temperature. Additionally, reusability test revealed that the catalyst is active even after five runs of hydrolytic reaction, implying the as-prepared NiO doped TiO2 nanofibers could be considered as a potential candidate catalyst for portable hydrogen fuel system such as PEMFC (proton exchange membrane fuel cells).

Diagnostic potential of monoclonal antibodies against the capsid protein of chikungunya virus for detection of recent infection.

Chikungunya fever is self-limiting. However, neurological and hemorrhagic complications have been seen in recent outbreaks. The clinical manifestations of this disease are similar to those of dengue virus infection, indicating the need for differential diagnosis in areas such as India, which are endemic for both viruses. The aim of the present study was to develop monoclonal antibodies (MAbs) against Chikungunya virus (CHIKV) and assess their use in MAb-based IgM capture ELISA (MAC ELISA). The ELISA detects CHIKV-specific IgM antibodies, a marker of recent infection, in a patient's serum. One IgG1 and two IgM isotype hybrids were obtained. All of the subclones derived from the IgG1 hybrid recognized the C protein of CHIKV. The anti-C MAb ClVE4/D9 was the most promising as a detector antibody in MAC ELISA (C-MAb ELISA) yielding higher positive-to-negative (P/N) ratios. When compared with the CHIKV MAC ELISA kit developed by the National Institute of Virology (NIV), Pune (NIV MAC ELISA), the sensitivity of the test was 87.01 % with 100 % specificity. The positive and negative predictive values (PPV and NPV) were 100 % and 94.47 %, respectively. In precision testing, standard deviation (SD) and coefficient of variation (% CV) values of the C-MAb ELISA were within acceptable limits. The C-MAb ELISA detected anti-CHIKV IgM in serum of patients up to five months after the onset of infection, indicating that anti-C MAbs have strong potential for use in MAC ELISA to detect recent CHIKV infection.

Controlled synthesis of ZnO from nanospheres to micro-rods and its gas sensing studies.

1D ZnO rods are synthesized using less explored hydrazine method. Here we find, besides being combustible hydrazine can also be used as a structure-directing agent. The ratio of zinc nitrate (ZN) to hydrazine is found to control the morphology of ZnO. At lower concentration of ZN as compared with hydrazine the morphology of ZnO is found to be spherical. As we increase the hydrazine content the morphology changes from spherical (diameter approximately 100 nm) to the elongated structures including shapes like Y, T as well dumbbell (diameter approximately 40 nm and length approximately 150 nm). Interestingly for more than 50% of hydrazine ZnO micro-rods are formed. Such rods are of diameter approximately 120 nm having length of about 1 microm for ZN to hydrazine ratio of 1:9, isolated as well as bundle of rods are seen in scanning electron microscopy (SEM). The X-ray diffraction (XRD) reveals the phase formation with average particle size of 37 nm as calculated using Scherrer's formula. The high-resolution transmission electron microscopy (HRTEM) is also done to confirm the d-spacing in ZnO. Gas sensing study for these samples shows high efficiency and selectivity towards LPG at all operating temperatures. Photoluminescence (PL) study for these samples is performed at room temperature to find potential application as photoelectric material.

Titania nanoparticles synthesis in mesoporous molecular sieve MCM-41.

Nanocrystalline titanium oxide (TiO(2)) is one of the most useful oxide material, because of its widespread applications in photocatalysis, solar energy conversion, sensors and optoelectronics. The control of particle size and monodispersity of TiO(2) nanoparticles is a challenging task. The use of MCM-41, an inorganic template of uniform pore size (2-10 nm), can overcome this difficulty and produce stable nanoparticles of uniform size and shape. Here, we demonstrate the synthesis of titania nanoparticles inside the pores of silica based MCM-41 forming a TiO(2)/Si-MCM composite. Composites are formed in the alcoholic medium by incipient wetness impregnation method. Titania particles of average 3 nm size are obtained. Effect of silica and titania precursors on the quality of nanoparticles has been investigated. The characterization of titania-MCM-41 composites has been carried out using a variety of techniques like UV-vis absorption spectroscopy, X-ray diffraction, FT-IR spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and photoluminescence spectroscopy. It has been found that the titania particles are co-ordinated with Si-MCM by SiOTi covalent bond.

Nitrate reductase-mediated synthesis of silver nanoparticles from AgNO3.

Synthesis of silver nanoparticles using alpha-NADPH-dependent nitrate reductase and phytochelatin in vitro has been demonstrated for the first time. The silver ions were reduced in the presence of nitrate reductase, leading to the formation of a stable silver hydrosol 10-25 nm diam. and stabilized by the capping peptide. The nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and UV-Vis absorption. These studies will help in designing a rational enzymatic strategy for the synthesis of nanomaterials of different chemical composition, shapes and sizes as well as their separation.

Thermally assisted semiconductor-like to insulator transition in gold-poly(methyl methacrylate) nanocomposites.

Gold-polymethylmethacrylate (PMMA) nanocomposites were fabricated by mixing gold nanoparticles capped with oleylamine in polymethylmethacrylate. The samples were analysed using UV-vis absorption spectroscopy, transmission electron microscopy, small angle x-ray scattering, Fourier transform infrared spectrometry (FTIR) and x-ray photoelectron spectroscopy (XPS). Electrical resistivity of nanocomposite samples was measured by a four-probe technique in the 70-300 K range. The nanocomposites showed a transition with an onset at ∼160-165 K. They exhibited a semiconductor-like conductivity at higher temperatures and nearly temperature independent conductivity at lower temperatures. The interfacial interaction of Au nanoparticles and PMMA polymer is investigated using FTIR and XPS. A ligand-exchange process occurs when capped gold nanoparticles are incorporated in PMMA polymer.

Low cost autologous peripheral blood stem cell transplantation performed in a municipal hospital for a patient with plasma cell leukaemia.

Autologous peripheral blood stem cell transplantation (PBSCT) is a costly procedure. In India, the cost varies from US$20000 to 25000 and most patients cannot afford it. Using several cost-cutting measures, we were able to treat a patient with plasma cell leukaemia by autologous PBSCT. A 42-year-old-male presented with plasma cell leukaemia. He was treated with VAD therapy, followed by high-dose cyclophosphamide and granulocyte colony-stimulating factor (G-CSF) for mobilization of peripheral blood stem cells. The patient was conditioned with high dose melphalan, followed by autologous PBSCT. The procedure was performed in a municipal hospital in which there was no prior experience with stem cell transplantation. Costs were reduced by: (i) using oral medication whenever possible; (ii) having a relative of the patient prepare his food under medical guidance; (iii) starting G-CSF on day 7 rather than on day 1; (iv) short-term storage of the PBSC in an ordinary refrigerator at 4 degrees C without cryopreservation; (v) infusing a large number of CD34+ cells, which shortened the time to engraftment; (vi) delegating many of the functions of a marrow transplant nurse to a resident physician. The cost of transplantation was thereby reduced to about US$ 6000, with successful engraftment by day +13. The patient remained in remission for 7 months, after which he relapsed and was treated with chemotherapy and electron beam radiation to the skin.