Human serum albumin nanoparticles loaded with phthalocyanine dyes for potential use in photodynamic therapy of atherosclerotic plaques

Diseases caused by obstruction or rupture of vulnerable plaques in the arterial walls such as cardiovascular infarction or stroke are the leading cause of death in the world. In the present work, we developed human serum albuminnanoparticles loaded by physisorption with zinc phthalocyanine, TT1, mainly used for industrial application as near-infrared photosensitizer and compared these to HSA NPsloaded with the well-known silicone phthalocyanine (Pc4). The use of NIR light allows for better tissue penetration, while the use of nanoparticles permitshigh local concentrations. The particles were characterized and tested for toxicity and stability as well as for their potential use as a contrast agent and NIR photosensitizer for photodynamic therapy in cardiovascular disease. We focused on the distribution of the nanoparticles in RAW264.7macrophage cells and atherosclerotic mice. The nanoparticles had an average size of 120 nm according todynamic light scattering, good loading capacity for zinc phthalocyanine,and satisfying stability in 50% (v/v) fetal bovine serum for 8 hours and in an aqueous environment at 4°C for 4–6 weeks. Under light irradiation we found a high production of singlet oxygen and the products showed no dark toxicity in vitro with macrophages(the target cells in vulnerable plaques),but at a low μg/mL nanoparticleconcentration killed efficiently the macrophagesupon LED illumination. Injection of the contrast agentin atherosclerotic mice led to a visible fluorescence signal of zinc phthalocyaninein the atherosclerotic plaque at 30 minutes and in the lungs with afast clearance of the nanoparticles. Zinc phthalocyanine loaded human serum albumin nanoparticles present an interesting candidate for the visualization and potentially photodynamictreatment of macrophages in atherosclerotic plaquesThe research leading to these results has received funding from FP7-NMP CosmoPHOS-Nano under grant agreement No. 310337. Additional funding was received by the Spanish groups from MINECO (CTQ2017-85393-P) and ERA-NET/MINECO EuroNanoMed2017-191 / PCIN-2017-04

Isolation of viable but nonculturable Vibrio cholerae O1 from environmental water samples in Kolkata, India, in a culturable state

Previously, we reported that viable but nonculturable (VBNC) Vibrio cholerae was converted into a culturable state by coculture with several eukaryotic cell lines including HT-29 cells. In this study, we found that a factor converting VBNC V. cholerae into a culturable state (FCVC) existed in cell extracts of eukaryotic cells. FCVC was nondialyzable, proteinase K-sensitive, and stable to heating at <60°C for 5 min. We prepared thiosulfate citrate bile salts sucrose (TCBS) plates with FCVC (F-TCBS plates). After confirming that VBNC V. cholerae O1 and O139 formed typical yellow colonies on F-TCBS plates, we tried to isolate cholera toxin gene-positive VBNC V. cholerae from environmental water samples collected in urban slum areas of Kolkata, India and succeeded in isolating V. cholerae O1 El Tor variant strains harboring a gene for the cholera toxin. The possible importance of VBNC V. cholerae O1 as a source of cholera outbreaks is discussed

Stearylamine-Bearing Cationic Liposomes Kill Leishmania parasites through Surface Exposed Negatively Charged Phosphatidylserine

Leishmania parasites are the causative agents for cutaneous and visceral leishmaniasis (VL) with �2 million cases annually and a prevalence rate of 12 million, respectively. VL, principally caused by Leishmania donovani, is fatal if left untreated.1 Pentavalent antimonials, though toxic, remain the first-line drugs for leishmaniasis. Emergence of drug resistance has pushed in second-line drugs such as amphotericin B and pentamidine, which cause toxic side effects.2–4 Miltefosine, the most recent oral drug for VL, is potentially teratogenic.2 Moreover, clinical trials have identified occasional gastrointestinal toxicity that requires treatment withdrawa

Aluminium complex–catalysed hydroboration of alkenes and alkynes

We demonstrate an efficient method for the hydroboration of terminal alkenes or alkynes with pinacolborane (HBpin) using the aluminium catalyst, [κ2-(Ph2P(=Se)NCH2(C5H4N)Al(CH3)2] (1), supported by a functionalized amidophosphine ligand under mild and solvent-free conditions to afford corresponding alkyl and alkenyl boronate esters in high yield. This protocol involves the chemoselective formation of an anti-Markovnikov product exclusively. Both terminal alkenes and alkynes bearing a wide array of electron-withdrawing as well as donating functional groups can easily be converted to the corresponding product through the formation of aluminum hydride as an active catalytic species

Alte Erinnerungen an das Elsass

Numérisé par le partenaireAppartient à l’ensemble documentaire : BNUStr001Appartient à l’ensemble documentaire : BNUStras1Numérisé par le partenair

Flower bud proteome reveals modulation of sex-biased proteins potentially associated with sex expression and modification in dioecious Coccinia grandis.

Dioecy is an important sexual system wherein, male and female flowers are borne on separate unisexual plants. Knowledge of sex-related differences can enhance our understanding in molecular and developmental processes leading to unisexual flower development. Coccinia grandis is a dioecious species belonging to Cucurbitaceae, a family well-known for diverse sexual forms. Male and female plants have 22A + XY and 22A + XX chromosomes, respectively. Previously, we have reported a gynomonoecious form (22A + XX) of C. grandis bearing morphologically hermaphrodite flowers (GyM-H) and female flowers (GyM-F). Also, we have showed that foliar spray of AgNO3 on female plant induces morphologically hermaphrodite bud development (Ag-H) despite the absence of Y-chromosome

Nanoscale On-Silico Electron Transport via Ferritins

Silicon is a solid-state semiconducting material that has long been recognized as a technologically useful one, especially in electronics industry. However, its application in the next-generation metalloprotein-based electronics approaches has been limited. In this work, the applicability of silicon as a solid support for anchoring the iron-storage protein ferritin, which has a semiconducting iron nanocore, and probing electron transport via the ferritin molecules trapped between silicon substrate and a conductive scanning probe has been investigated. Ferritin protein is an attractive bioelectronic material because its size (X-ray crystallographic diameter ∼12 nm) should allow it to fit well in the larger tunnel gaps (>5 nm), fabrication of which is relatively more established, than the smaller ones. The electron transport events occurring through the ferritin molecules that are covalently anchored onto the MPTMS-modified silicon surface could be detected at the molecular level by current-sensing atomic force spectroscopy (CSAFS). Importantly, the distinct electronic signatures of the metal types (i.e., Fe, Mn, Ni, and Au) within the ferritin nanocore could be distinguished from each other using the transport band gap analyses. The CSAFS measurements on holoferritin, apoferritin, and the metal core reconstituted ferritins reveal that some of these ferritins behave like n-type semiconductors, while the others behave as p-type semiconductors. The band gaps for the different ferritins are found to be within 0.8 to 2.6 eV, a range that is valid for the standard semiconductor technology (e.g., diodes based on p–n junction). The present work indicates effective on-silico integration of the ferritin protein, as it remains functionally viable after silicon binding and its electron transport activities can be detected. Potential use of the ferritin–silicon nanohybrids may therefore be envisaged in applications other than bioelectronics, too, as ferritin is a versatile nanocore-containing biomaterial (for storage/transport of metals and drugs) and silicon can be a versatile nanoscale solid support (for its biocompatible nature)

Immune responses in kala-azar

Human infection with Leishmania results in diverse clinical and immunopathological situations. The capacity of the parasites to cause this wide range of disease manifestations depends upon their ability to evade the immune defense mechanisms by performing a well-tuned orchestra of hostparasite interactions inside the macrophages. While updated knowledge focus on the key role of cell-mediated immunity (CMI) in protection, the survival strategies of the parasites leads to the suppression of CMI which can further be aggravated by the co-infections with HIV, tuberculosis etc. The present review describes the immune mechanisms in human leishmaniasis with a special attention to visceral leishmaniasis or kala-azar, one of the most important epidemiological health problems in Indian subcontinent. Modulations of the both humoral and cell-mediated immune responses during asymptomatic infections, active disease and after successful chemotherapy are discussed. The components responsible for the regulation of the critical balance of Th1/Th2 type of responses are re-evaluated. Co-infection of HIV and visceral leishmaniasis and their interdependence has been addressed. Although the specific role of an elevated humoral response in kala-azar is yet to be established, attempts for its application in diagnosis, precisely for the development of field diagnostic techniques, are presented. Also discussed are attempts to utilize the immunogenic potentials of different leishmanial antigens in the development of anti-leishmanial vaccines