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Autophagy is a cellular response to adverse environment and stress, but its significance in cell survival is not always clear. Here we show that autophagy could be induced in the mammalian cells by chemicals, such as A23187, tunicamycin, thapsigargin, and brefeldin A, that cause endoplasmic reticulum stress. Endoplasmic reticulum stress-induced autophagy is(More)
There is growing evidence demonstrating the complexity of melatonin's role in modulating a diverse number of physiological processes. This complexity could be attributed to the fact that melatonin receptors belong to two distinct classes of proteins, that is, the G-protein coupled receptor superfamily (MT(1), MT(2)) and the quinone reductase enzyme family(More)
Immunofluorescence microscopy is widely used to characterize the cellular distribution of both soluble and structural proteins. Control experiments generally address only the specificity of the antibodies used. The permeabilization/fixation conditions used to prepare cells for antibody application are assumed to preserve faithfully the in vivo distributions(More)
Bacteria that simultaneously produce multiple extended-spectrum beta-lactamases are frequently isolated. We report an Enterobacter cloacae isolate, ES24, producing four different beta-lactamases (AmpC type beta-lactamase, TEM-1, SHV-7, and a novel extended-spectrum beta-lactamase, SHV-30). Direct sequencing of bla(SHV) gene products gave a "double peak" at(More)
We isolated and characterized a 2.8-kb, full-length, Arabidopsis thaliana cDNA clone encoding a lipoxygenase. DNA sequence analysis showed that the deduced amino acid sequence of the Arabidopsis protein is 72 to 78% similar to that of legume seed lipoxygenases. DNA blot analysis indicated that Arabidopsis contains a single gene, LOX1, with appreciable(More)
MT1 melatonin receptors expressed in Chinese hamster ovary (CHO) cells remain sensitive to a melatonin re-challenge even following chronic melatonin exposure when microtubules are depolymerized in the cell, an exposure that normally results in MT1 receptor desensitization. We extended our findings to MT2 melatonin receptors using both in vitro and in vivo(More)
BACKGROUND Genital infections due to herpes simplex virus type 2 (HSV-2) are characterized by frequent reactivation and shedding of the virus and by the attendant risk of transmission to sexual partners. We investigated the effects of vaginal coinfections and hormonal contraceptive use on genital tract shedding of HSV-2 in women. METHODS A total of 330(More)
There are conflicting claims for the role of melatonin in oncogenesis. In addition, the mechanism(s) underlying melatonin's effects in oncogenic processes is (are) unknown. In this study, the effects of melatonin exposure on cell proliferation and transformation were assessed in NIH3T3 cells transfected with either the human mt(1) (NIH-mt1) or MT(2)(More)
Chronic melatonin exposure produces microtubule rearrangements in Chinese hamster ovary (CHO) cells expressing the human MT1 melatonin receptor while at the same time desensitizing MT1 receptors. Because microtubule rearrangements parallel MT1 receptor desensitization, we tested whether microtubules modulate receptor responsiveness. We determined whether(More)
In this investigation, we wanted to determine whether MT(1) or MT(2) melatonin receptors are capable of coupling to the phosphoinositide (PI) signal transduction cascade. In addition, we wanted to assess the effects of chronic melatonin exposure on MT(1) and MT(2) melatonin receptor-mediated stimulation of PI hydrolysis. We also assessed the effects of(More)