Differential influence of DNA supercoiling on in vivo strength of promoters varying in structure and organisation in E. coli

AbstractDNA supercoiling is known to influence promoter activity in vitro and in vivo in a promoter-dependent manner in prokaryotes. In order to investigate how topology may influence promoter function, we have studied two kinds of promoter variants, (i) where only the spacer region is altered, and (ii) where the same promoter is tandemly repeated in either the same or opposite orientation. These promoters respond very differently to alterations in DNA supercoiling, suggesting that the overall structure of the promoter and its context contribute to the differential response to alterations in supercoiling in vivo

Motion Sickness Manifestations and Prevention

Motion sickness is an ancient problem associated with transportation (ships and other vehicles), which is affecting humans since ages. Motion sickness is characteristically occurring during abnormal movements induced by the motion and when there is a conflict between various senses such as visual, vestibular and motor system. Depending on the type of motion, various kinds of sicknesses, such as air sickness, car sickness, train sickness, seasickness, etc. may occur. A very less per cent of individuals are highly susceptible to motion sickness and very less per cent of individuals are highly insusceptible for motion sickness. However, most of the population comes in between. The primary symptoms of motion sickness include nausea, vomiting, wanes, and cold sweating. Varieties of drugs are available to reduce susceptibility to motion sickness. However, nausea, pallor, sweating, headache, dizziness, malaise, increased salivation, apathy, drowsiness, belching, hyperventilation and stomach awareness are the other symptoms of motion sickness. Anti-cholinergics and anti-histamines are the most effective motion sickness prophylactics with apparent side effects such as dry mouth, drowsiness, and depression. There are theories and mechanisms which include intra-vestibular (Canal-Otolith) mismatch theory, sensory conflict theory, visual-vestibular mismatch theory, the poison theory, the postural instability theory, and the movement program theory. Benzodiazepines, anticholinergics, anti-histamines and monoamine antagonists have commonly used treatment regimes. The traditional way of tackling the problem is the consumption of ginger, peppermint, lemon, fennel, marjoram, rosemary, basil. This review summarizes prediction and evaluation, behavioural strategies to prevent or minimize symptoms of motion sickness and available countermeasures of motion sickness

Large Bilateral Symptomatic Pelvic Lymphoceles Following a Radical Prostatectomy

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Tetrathiomolybdate sensitizes ovarian cancer cells to anticancer drugs doxorubicin, fenretinide, 5-fluorouracil and mitomycin C

<p>Abstract</p> <p>Background</p> <p>Our recent study showed that tetrathiomolybdate (TM), a drug to treat copper overload disorders, can sensitize drug-resistant endometrial cancer cells to reactive oxygen species (ROS)-generating anticancer drug doxorubicin. To expand these findings in the present study we explore TM efficacy in combination with a spectrum of ROS-generating anticancer drugs including mitomycin C, fenretinide, 5-fluorouracil and doxorubicin in ovarian cancer cells as a model system.</p> <p>Methods</p> <p>The effects of TM alone or in combination with doxorubicin, mitomycin C, fenretinide, or 5-fluorouracil were evaluated using a sulforhodamine B assay. Flow cytometry was used to detect the induction of apoptosis and ROS generation. Immunoblot analysis was carried out to investigate changes in signaling pathways.</p> <p>Results</p> <p>TM potentiated doxorubicin-induced cytotoxicity and modulated key regulators of apoptosis (PARP, caspases, JNK and p38 MAPK) in SKOV-3 and A2780 ovarian cancer cell lines. These effects were linked to the increased production of ROS, as shown in SKOV-3 cells. ROS scavenging by ascorbic acid blocked the sensitization of cells by TM. TM also sensitized SKOV-3 to mitomycin C, fenretinide, and 5-fluorouracil. The increased cytotoxicity of these drugs in combination with TM was correlated with the activity of ROS, loss of a pro-survival factor (e.g. XIAP) and the appearance of a pro-apoptotic marker (e.g. PARP cleavage).</p> <p>Conclusions</p> <p>Our data show that TM increases the efficacy of various anticancer drugs in ovarian cancer cells in a ROS-dependent manner.</p

Organometallic Iron(III)-Salophene Exerts Cytotoxic Properties in Neuroblastoma Cells via MAPK Activation and ROS Generation

The objective of the present study was to investigate the specific effects of Iron(III)-salophene (Fe-SP) on viability, morphology, proliferation, cell cycle progression, ROS generation and pro-apoptotic MAPK activation in neuroblastoma (NB) cells. A NCI-DTP cancer screen revealed that Fe-SP displayed high toxicity against cell lines of different tumor origin but not tumor type-specificity. In a viability screen Fe-SP exhibited high cytotoxicity against all three NB cell lines tested. The compound caused cell cycle arrest in G1 phase, suppression of cells progressing through S phase, morphological changes, disruption of the mitochondrial membrane depolarization potential, induction of apoptotic markers as well as p38 and JNK MAPK activation, DNA degradation, and elevated generation of reactive oxygen species (ROS) in SMS-KCNR NB cells. In contrast to Fe-SP, non-complexed salophene or Cu(II)-SP did not raise ROS levels in NB or SKOV-3 ovarian cancer control cells. Cytotoxicity of Fe-SP and activation of caspase-3, -7, PARP, pro-apoptotic p38 and JNK MAPK could be prevented by co-treatment with antioxidants suggesting ROS generation is the primary mechanism of cytotoxic action. We report here that Fe-SP is a potent growth-suppressing and cytotoxic agent for in vitro NB cell lines and, due to its high tolerance in previous animal toxicity studies, a potential therapeutic drug to treat NB tumors in vivo

An Adaptive Chlamydia trachomatis-Specific IFN-γ-Producing CD4+ T Cell Response Is Associated With Protection Against Chlamydia Reinfection in Women

Background: Adaptive immune responses that mediate protection against Chlamydia trachomatis (CT) remain poorly defined in humans. Animal chlamydia models have demonstrated that CD4+ Th1 cytokine responses mediate protective immunity against reinfection. To better understand protective immunity to CT in humans, we investigated whether select CT-specific CD4+ Th1 and CD8+ T cell cytokine responses were associated with protection against CT reinfection in women. Methods: Peripheral blood mononuclear cells were collected from 135 CT-infected women at treatment and follow-up visits and stimulated with CT antigens. CD4+ and CD8+ T-cells expressing IFN-γ, TNF-α, and/or IL-2 were assessed using intracellular cytokine staining and cytokine responses were compared between visits and between women with vs. without CT reinfection at follow-up. Results: A CD4+TNF-α response was detected in the majority (77%) of study participants at the treatment visit, but a lower proportion had this response at follow-up (62%). CD4+ IFN-γ and CD4+ IL-2 responses occurred less frequently at the treatment visit (32 and 18%, respectively), but increased at follow-up (51 and 41%, respectively). CD8+ IFN-γ and CD8+ TNF-α responses were detected more often at follow-up (59% for both responses) compared to the treatment visit (30% for both responses). At follow-up, a CD4+IFN-γ response was detected more often in women without vs. with reinfection (60 vs. 33%, P = 0.005). Conclusions: Our findings suggest that a CT-specific CD4+ IFN-γ response is associated with protective immunity against CT reinfection and is thus an important component of adaptive immunity to CT in women

Metabolic Tumor Profiling with pH, Oxygen, and Glucose Chemosensors on a Quantum Dot Scaffold

Acidity, hypoxia, and glucose levels characterize the tumor microenvironment rendering pH, pO2, and pGlucose, respectively, important indicators of tumor health. To this end, understanding how these parameters change can be a powerful tool for the development of novel and effective therapeutics. We have designed optical chemosensors that feature a quantum dot and an analyte-responsive dye. These noninvasive chemosensors permit pH, oxygen, and glucose to be monitored dynamically within the tumor microenvironment by using multiphoton imaging.National Cancer Institute (U.S.) (Grant R01-CA126642

Micelle-Encapsulated Quantum Dot-Porphyrin Assemblies as

Micelles have been employed to encapsulate the supramolecular assembly of quantum dots with palladium(II) porphyrins for the quantification of O₂ levels in aqueous media and in vivo. Förster resonance energy transfer from the quantum dot (QD) to the palladium porphyrin provides a means for signal transduction under both one- and two-photon excitation. The palladium porphyrins are sensitive to O₂ concentrations in the range of 0–160 Torr. The micelle-encapsulated QD-porphyrin assemblies have been employed for in vivo multiphoton imaging and lifetime-based oxygen measurements in mice with chronic dorsal skinfold chambers or cranial windows. Our results establish the utility of the QD-micelle approach for in vivo biological sensing applications.National Cancer Institute (U.S.) (R01- CA126642)International Society for Neurochemistry (W911NF-07-D-0004)United States. Dept. of Energy. Office of Basic Energy Sciences (DE-SC0009758