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This article examines the indoor air quality (IAQ) in coal-heating rural residential buildings in Northern China during the heating period. The study found that many households had poor indoor air quality, with high levels of CO2, formaldehyde, and PM2.5. The study also discovered that indoor PM2.5 was primarily caused by indoor activities rather than outdoor pollution. The findings emphasize the need for improving IAQ in rural areas and provide data to support future interventions. The study suggests using appropriate ventilation methods and clean fuel for cooking to improve indoor air quality. [Extracted from the article]

Abstract??The involvement and potential interdependence of inositol trisphosphate (IP3) receptors and Bcl-2 in the regulation of Ca2signaling is not clear. Here, we have explored the mechanism(s) of how Bcl-2 suppresses the IP3-sensitive Ca2release in MCF-7 cells focusing on the possible role of protein phosphatase 1 (PP1). We found that through influences on protein?protein interaction, Bcl-2 may alter the balance between the effects of phosphatase (PP1) and kinase (PKA) on the IP3 R1 signaling complex. Using various experimental approaches including phosphatase inhibition and RNAi, we show that Bcl-2 by competing with IP3R1 for the binding of PP1 can reduce the IP3-mediated calcium signal and protect cells from mitochondrial dysfunction and cell death. [ABSTRACT FROM AUTHOR]

Bcl-2 inhibits apoptosis by regulating the release of cytochrome c and other proteins from mitochondria. Oligomerization of Bax promotes cell death by permeabilizing the outer mitochondrial membrane. In transfected cells and isolated mitochondria, Bcl-2, but not the inactive point mutants Bcl-2-G145A and Bcl-2-V159D, undergoes a conformation change in the mitochondrial membrane in response to apoptotic agonists such as tBid and Bax. A mutant Bcl-2 with two cysteines introduced at positions predicted to result in a disulfide bond that would inhibit the mobility of α5–α6 helices (Bcl-2-S105C/E152C) was only active in a reducing environment. Thus, Bcl-2 must change the conformation to inhibit tBid-induced oligomerization of integral membrane Bax monomers and small oligomers. The conformationally changed Bcl-2 sequesters the integral membrane form of Bax. If Bax is in excess, apoptosis resumes as Bcl-2 is consumed by the conformational change and in complexes with Bax. Thus, Bcl-2 functions as an inhibitor of mitochondrial permeabilization by changing conformation in the mitochondrial membrane to bind membrane-inserted Bax monomers and prevent productive oligomerization of Bax. [ABSTRACT FROM AUTHOR]

The S2 domain of the severe acute respiratory syndrome coronavirus (SARS-CoV) spike (S) protein is responsible for fusion between virus and target cell membranes, and is expected to be immungenic. In this study, we investigated the immune responses against the S2 subunit in BALB/c mice, which were vaccinated either with plasmid DNA encoding the S2 domain (residues 681–1120), the recombinant S2 fragment (residues 681–980) in incomplete Freund's adjuvant, or with inactivated SARS-CoV. The increased number of specific cytotoxic cells (CTLs) and the high titer of specific antibody showed stimulation of both arms of the immune system in these groups. The shift in cytokines suggested that Th1–polarized immune response was induced by plasmid pCoVS2, meanwhile the Th2-dominant response was induced by recombinant S2 fragment and inactivated vaccine. However, the titer of neutralizing antibodies was only detectable in mice immunized with inactivated virus, but not with pCoVS2 plasmid. Taken together, the S2 domain could induce specific cellular immune response and a high level of total IgG but little neutralizing antibodies against infection by SARSCoV. [ABSTRACT FROM AUTHOR]

Abstract The regulation of mitochondrial permeability transition (MPT) is essential for cell survival. Un-controlled opening of the MPT pore is often associated with cell death. Anti-death protein Bcl-2 can block MPT as assessed by the enhanced capacity of mitochondria to accumulate and retain Ca2+. We report here that two proteins of the mitochondrial fission machinery, dynamin-related protein (Drp1) and human mitochondrial fission protein (hFis1), have an antagonistic effect on Bcl-2. Drp1, with the assistance of hFis1, sensitizes cells to MPT by reducing the mitochondrial Ca2+ retention capacity (CRC). While the reduction of CRC by Drp1/hFis1 is linked to mitochondrial fission, the antagonism between Bcl-2 and Drp1 appears to be mediated by mutually exclusive interactions of the two proteins with hFis1. The complexity of protein–protein interactions demonstrated in the present study suggests that in addition to the previously described role of Bcl-2 in the control of apoptosis, Bcl-2 may also participate directly or indirectly in the regulation of mitochondrial fission. [ABSTRACT FROM AUTHOR]

Cellular adhesion is regulated by members of the cadherin family of adhesion receptors and their cytoplasmic adaptor proteins, the catenins. Adhesion complexes are regulated by recycling from the plasma membrane and proteolysis during apoptosis. We report that in MCF-7, MDA-MB-468 and MDCK cells, induction of apoptosis by agents that cause endoplasmic reticulum (ER) stress results in O-glycosylation of both β-catenin and the E-cadherin cytoplasmic domain. O-glycosylation of newly synthesized E-cadherin blocks cell surface transport, resulting in reduced intercellular adhesion. O-glycosylated E-cadherin still binds to β- and γ-catenin, but not to p120-catenin. Although O-glycosylation can be inhibited with caspase inhibitors, cleavage of caspases associated with the ER or Golgi complex does not correlate with E-cadherin O-glycosylation. However, agents that induce apoptosis via mitochondria do not lead to E-cadherin O-glycosylation, and decrease adhesion more slowly. In MCF-7 cells, this is due to degradation of E-cadherin concomitant with cleavage of caspase-7 and its substrate poly(ADP-ribose) polymerase. We conclude that cytoplasmic O-glycosylation is a novel, rapid mechanism for regulating cell surface transport exploited to down-regulate adhesion in some but not all apoptosis pathways. [ABSTRACT FROM AUTHOR]

Our laboratory was one of the first to discover that the topoisomerase II inhibitors etoposide (VP-16) and teniposide (VM-26) synergistically enhanced TNF-mediated apoptosis of some human tumor cells. To probe the mechanism of cytotoxic synergy, we have examined pro- and antiapoptotic pathways in cells that show enhanced tumor cell death. ME-180 human cervical carcinoma cells treated with VP-16 and VM-26 showed no significant changes in NF-κB or IκB protein levels within the first 8h after treatment. NF-κB translocated into the nucleus following treatment with TNF or TNF and VM-26, but not with VM-26 alone, suggesting that the enhancement of TNF cytotoxicity by topoisomerase 11 inhibitors is not due to a global inhibition of NF-κB nuclear translocation. When treated TNF alone, a sharp increase in the levels of phospho-JNK (p-JNK) was observed at 0.5h, which declined at 1h, and almost disappeared at 2h. Treatment with TNF and VP-16 caused a second increase in p-JNK levels at 2h, which was not seen in cells incubated with TNF alone. The translocation of p-JNK into the nucleus was observed 2h after cells were treated with TNF, but not with VM-26 However, the combination of TNF and VM-26 showed increased nuclear translocation of p-JNK. Future experiments will address the potential role of the second JNK activation event in the enhancement of TNF cytotoxicities by these topoisomerase II inhibitors. [ABSTRACT FROM AUTHOR]