ESX-1-induced apoptosis is involved in cell-to-cell spread of Mycobacterium tuberculosis.

Apoptosis modulation is a procedure amply utilized by intracellular pathogens to favour the outcome of the infection. Nevertheless, the role of apoptosis during infection with Mycobacterium tuberculosis, the causative agent of human tuberculosis, is subject of an intense debate and still remains unclear. In this work, we describe that apoptosis induction in host cells is clearly restricted to virulent M. tuberculosis strains, and is associated with the capacity of the mycobacteria to secrete the 6 kDa early secreted antigenic target ESAT-6 bothunder in vitro and in vivo conditions. Remarkably, only apoptosis-inducing strains are able to propagate infection into new cells, suggesting that apoptosis is used by M. tuberculosis as a colonization mechanism. Finally, we demonstrate that in vitro modulation of apoptosis affects mycobacterial cell-to-cell spread capacity, establishing an unambiguous relationship between apoptosis and propagation of M. tuberculosis. Our data further indicate that BCG and MTBVAC vaccines are inefficient in inducing apoptosis and colonizing new cells, correlating with the strong attenuation profile of these strains previously observed in vitro and in vivo.

Quantity, distribution and phenotype of newly generated cells in the intact spinal cord of adult macaque monkeys.

The existence of proliferating cells in the intact spinal cord, their distribution and phenotype, are well studied in rodents. A limited number of studies also address the proliferation after spinal cord injury, in non-human primates. However, a detailed description of the quantity, distribution and phenotype of proliferating cells at different anatomical levels of the intact adult non-human primate spinal cord is lacking at present. In the present study, we analyzed normal spinal cord tissues from adult macaque monkeys (Macaca fuscata), infused with Bromo-2'-deoxyuridine (BrdU), and euthanized at 2h, 2 weeks, 5 weeks and 10 weeks after BrdU. We found a significantly higher density of BrdU + cells in the gray matter of cervical segments as compared to thoracic or lumbar segments, and a significantly higher density of proliferating cells in the posterior as compared to the anterior horn of the gray matter. BrdU + cells exhibited phenotype of microglia or endothelial cells (∼50%) or astroglial and oligodendroglial cells (∼40%), including glial progenitor phenotypes marked by the transcription factors Sox9 and Sox10. BrdU + cells also co-expressed other transcription factors known for their involvement in embryonic development, including Emx2, Sox1, Sox2, Ngn1, Olig1, Olig2, Olig3. In the central canal, BrdU + cells were located along the dorso-ventral axis and co-labeled for the markers Vimentin and Nestin. These results reveal the extent of cellular plasticity in the spinal cord of non-human primates under normal conditions.

Stress protein Hsp27 expression predicts the outcome in operated small cell lung carcinoma and large cell neuroendocrine carcinoma patients.

PURPOSE: Heat shock protein (Hsp)27 is overexpressed in a range of human cancers and is implicated in tumor cell proliferation, differentiation, invasion, metastasis, and survival. The aim of the present study was to determine the prognostic significance of Hsp27 expression in small cell lung carcinoma (SCLC) and large cell neuroendocrine carcinoma (LCNEC). METHODS: Surgically resected SCLCs (N=51) and LCNECs (N=15) were studied. The Hsp27 expression was detected immunohistochemically. RESULTS: Hsp27 positive immunoreaction in the cytoplasm was observed in 45 (88%) SCLCs and 14 (93%) LCNECs. A combination of cytoplasmic with nuclear Hsp27 expression was observed in 28 (62%) SCLCs and 14 (100%) LCNECs. There was a correlation between Hsp27 cytoplasmic overexpression and Hsp27 nuclear expression with patient survival confirmed by Cox multivariate analysis. CONCLUSION: We conclude that the higher Hsp27 cytoplasmic expression and nuclear expression may represent favorable prognostic factors in SCLC and LCNEC.

Redox properties of alluaudite sodium cobalt manganese sulfates as high-voltage electrodes for rechargeable batteries.

Alluaudite sulfates are predicted to be high-voltage electrodes for lithium- and sodium-ion batteries. Herein, we provide the first experimental evidence for the operation of sodium cobalt-manganese sulfate, Na2+2δ(Co0.63Mn0.37)2-δ(SO4)3, at potentials higher than 4.0 V vs. Li/Li+. This fact comes as a result of the reduced cationic deficiency, redox properties of Co and Mn and stability of the alluaudite structure during alkali ion intercalation.

Infrared spectroscopic study of SO4²â» ions included in M'2M''(SeO4)2⋠6H2O (Me'=K, NH4⁺; M''=Mg, Co, Ni, Cu, Zn) and NH4⁺ ions included in K2M(XO4)2⋠6H2O (X=S, Se; M''=Mg, Co, Ni, Cu, Zn).

Infrared spectra of Tutton compounds, M'2M''(SeO4)2⋅6H2O (M'=K, NH4⁺; M''=Mg, Co, Ni, Cu, Zn; X=S, Se), as well as those of SO4²â» guest ions included in selenate host lattices and of NH4(+) guest ions included in potassium host lattices are presented and discussed in the regions of ν3 and ν1 of SO4²â» guest ions, ν4 of NH4⁺ guest ions and water librations. The SO4²â» guest ions matrix-isolated in selenate matrices (approximately 2 mol%) exhibit three bands corresponding to ν3 and one band corresponding to ν1 in good agreement with the low site symmetry C1 of the host selenate ions. When the larger SO4²â» ions are replaced by the smaller SO4²â» ions the mean values of the asymmetric stretching modes ν3 of the included SO4²â» ions are slightly shifted to lower frequencies as compared to those of the same ions in the neat sulfate compounds due to the smaller repulsion potential of the selenate matrices (larger unit-cell volumes of the selenates). It has been established that the extent of energetic distortion of the sulfate ions matrix-isolated in the ammonium selenates as deduced from the values of Δν3 and Δν3/νc is stronger than that of the same ions matrix-isolated in the potassium selenates due to the formation of hydrogen bonds between the SO4²â» guest ions with both the water molecules in the host compounds and the NH4⁺ host ions (for example, Δν3 of the sulfate guest ions have values of 30 and 51 cm(-1) in the nickel potassium and ammonium compounds, and 33 and 49 cm(-1) in the zinc potassium and ammonium compounds, respectively). The infrared spectra of ammonium doped potassium sulfate matrices show three bands corresponding to Δν4 of the included ammonium ions in agreement with the low site symmetry C1 of the host potassium ions. However, the inclusion of ammonium ions in selenate matrices (with exception of the magnesium compound) leads to the appearance of four bands in the region of ν4. At that stage of our knowledge we assume that some kind of disorder of the ammonium ions included in selenate lattices occurs due to the different proton acceptor capability of the SO4²â» and SO4²â» ions. The latter ions are known to exhibit stronger proton acceptor abilities. This fact will facilitate the formation of polyfurcate hydrogen bonds of the ammonium ions in the selenate matrices, thus leading to increasing in the coordination number of these ions, i.e. to a disorder of the ammonium guest ions. The strength of the hydrogen bonds formed in the title Tutton compounds as well as that of the hydrogen bonds in potassium compounds containing isomorphously included ammonium ions as deduced from the wavenumbers of the water librations are also discussed. The bands corresponding to water librations in the spectra of the mixed crystals K1.8(NH4)0.2M(XO4)2⋅6H2O (M=Mg, Co, Ni, Cu, Zn; X=S, Se) broaden and shift to lower frequencies as compared to those of the potassium host compounds, thus indicating that weaker hydrogen bonds are formed in the mixed crystals. These spectroscopic findings are owing to the decrease in the proton acceptor capacity of the SO4²â» and SO4²â» ions due to the formation of hydrogen bonds between the host anions and the guest ammonium cations additionally to water molecules (anti-cooperative or proton acceptor competitive effect). Furthermore, the band shifts in the spectra of the selenate matrices are generally larger than those observed in the spectra of the respective sulfates due to the stronger proton acceptor ability of the selenate ions.

Current activity and perspectives of Clinical and Transplantation Immunology Division, Medical University, Sofia, Bulgaria.

Our unit was established in 1972 as Laboratory of Clinical Immunology in the Department of Nephrology, Medical Academy, Sofia Since 1985 it was expanded in Division of Clinical and Transplantation Immunology. Transplantation activity includes: HLA typing (serology and DNA) of all kind of recipients and donors, alloantibody screening and crossmatching (basic microlymphocytotoxicity, DTT and flowcytometry tests). Immunologic evaluation of patients prior to and after transplantation is also performed for individualization of immunosuppressive therapy and discrimination between rejection, CMV infection and cyclosporine toxicity. Since 1983 till now 1662 candidates for kidney transplantation were immunologically tested and registered in Bulgaria. During the same period 293 donors (109 cadaveric and 184 living related) were also typed. The number of transplanted patients from the waiting list is 221. 123 transplantations (76 from cadaveric and 52 from living related donors) were performed in our country and the rest abroad. Because of the imbalance in numbers between cadaveric and living related donors and recipients, the waiting time for transplant candidates has increased, and tragically, the high percentage of patients are dying or become unsuitable while awaiting transplantation. In the field of bone marrow transplantation our laboratory performs the tissue typing of patients and all available members of the immediate family in order to search for histocompatible sibling donor. As recipient numbers continue to grow, both in absolute terms and relative to the number of available donor organs, our histocompatibility laboratory attempts to provide the best possible immune testing to ensure an optimal transplant outcome.

Effect of neurotensin on the canine gallbladder motility: in vivo and in vitro experiments.

Neurotensin (NT) (10(-8)-10(-6)) exerted a dose-dependent increase in the tone and release of [3H]ACh in the guinea-pig gallbladder muscle strips but was inefficient in the canine gallbladder muscle strips. However, in conscious dogs NT (2.5-20 ng/kg intravenously (i.v.)) dose-dependently increased the gallbladder pressure. Similar was the effect of CCK8 (1-10 ng/kg i.v.) and carbachol (0.5-2 micrograms/kg i.v.). The NT- or CCK8-induced gallbladder pressure was inhibited by atropine (10-50 micrograms/kg i.v.) or hexamethonium (0.5-3 mg/kg i.v.). Somatostatin (1-2 micrograms/kg i.v.) or VIP (0.5-1 microgram/kg i.v.) also reduced or even abolished the NT- or CCK8-induced gallbladder pressure. The NT-induced increase of the tone of guinea-pig gallbladder preparations was accompanied by an increase of [3H]ACh release, suggesting the involvement of cholinergic innervation.

Measuring the total value of a river cleanup.

The paper estimates the total value for the community of the cleanup of the Buriganga River. Dhaka, the capital of Bangladesh, was developed on the bank of the Buriganga River in the early 1600s. The river is now near dead mainly due to human interventions. The paper develops a hypothetical cleanup programme to improve the water quality, which will help the overall environment in and around the river. The value of this programme is estimated within the framework of total economic value; non-marketed benefits are measured through a contingent valuation survey and marketed benefits are estimated using market and shadow prices. The findings of the survey suggest that not only are a significant proportion of the residents willing to pay for the cleanup programme, but many are also willing to contribute in non-monetary ways (mainly their time). When the latter contribution is monetised, it represents 60% of the total value for the non-marketed benefits. The marketed benefits are estimated to represent 58% of the overall value of the cleanup programme (18.6 million US dollars/year). A failure to account for all benefits could lead to a gross underestimation of the desirability of providing public funding for the cleanup of dying rivers.

Bim is a crucial regulator of apoptosis induced by Mycobacterium tuberculosis.

Mycobacterium tuberculosis, the causative agent of tuberculosis, induces apoptosis in infected macrophages in vitro and in vivo. However, the molecular mechanism controlling this process is not known. In order to study the involvement of the mitochondrial apoptotic pathway in M. tuberculosis-induced apoptosis, we analysed cell death in M. tuberculosis-infected embryonic fibroblasts (MEFs) derived from different knockout mice for genes involved in this route. We found that apoptosis induced by M. tuberculosis is abrogated in the absence of Bak and Bax, caspase 9 or the executioner caspases 3 and 7. Notably, we show that MEF deficient in the BH3-only BCL-2-interacting mediator of cell death (Bim) protein were also resistant to this process. The relevance of these results has been confirmed in the mouse macrophage cell line J774, where cell transfection with siRNA targeting Bim impaired apoptosis induced by virulent mycobacteria. Notably, only infection with a virulent strain, but not with attenuated ESX-1-defective strains, such as Bacillus Calmette-Guerin and live-attenuated M. tuberculosis vaccine strain MTBVAC, induced Bim upregulation and apoptosis, probably implicating virulence factor early secreted antigenic target 6-kDa protein in this process. Our results suggest that Bim upregulation and apoptosis is mediated by the p38MAPK-dependent pathway. Our findings show that Bim is a master regulator of apoptosis induced by M. tuberculosis.