Shared and Unique Evolutionary Trajectories to Ciprofloxacin Resistance in Gram-Negative Bacterial Pathogens.

Resistance to the broad-spectrum antibiotic ciprofloxacin is detected at high rates for a wide range of bacterial pathogens. To investigate the dynamics of ciprofloxacin resistance development, we applied a comparative resistomics workflow for three clinically relevant species of Gram-negative bacteria: Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa. We combined experimental evolution in a morbidostat with deep sequencing of evolving bacterial populations in time series to reveal both shared and unique aspects of evolutionary trajectories.

Loss of LZAP inactivates p53 and regulates sensitivity of cells to DNA damage in a p53-dependent manner.

Chemotherapy and radiation, the two most common cancer therapies, exert their anticancer effects by causing damage to cellular DNA. However, systemic treatment damages DNA not only in cancer, but also in healthy cells, resulting in the progression of serious side effects and limiting efficacy of the treatment. Interestingly, in response to DNA damage, p53 seems to play an opposite role in normal and in the majority of cancer cells-wild-type p53 mediates apoptosis in healthy tissues, attributing to the side effects, whereas mutant p53 often is responsible for acquired cancer resistance to the treatment.

LZAP is a novel Wip1 binding partner and positive regulator of its phosphatase activity in vitro.

The phosphatase Wip1 attenuates the DNA damage response (DDR) by removing phosphorylation marks from a number of DDR proteins (p53, MDM2, Chk1/2, p38). Wip1 also dephosphorylates and inactivates RelA. Notably, LZAP, a putative tumor suppressor, has been linked to dephosphorylation of several of these substrates, including RelA, p38, Chk1, and Chk2.

Activin upregulation by NF-κB is required to maintain mesenchymal features of cancer stem-like cells in non-small cell lung cancer.

Soluble growth factors and cytokines within the tumor microenvironment aid in the induction of the epithelial-to-mesenchymal transition (EMT). Although EMT promotes the development of cancer-initiating cells (CIC), cellular mechanisms by which cancer cells maintain mesenchymal phenotypes remain poorly understood. Work presented here indicates that induction of EMT stimulates non-small cell lung cancer (NSCLC) to secrete soluble factors that function in an autocrine fashion.

Epigenetic coordination of signaling pathways during the epithelial-mesenchymal transition.

Background: The epithelial-mesenchymal transition (EMT) is a de-differentiation process required for wound healing and development. In tumors of epithelial origin aberrant induction of EMT contributes to cancer progression and metastasis. Studies have begun to implicate epigenetic reprogramming in EMT; however, the relationship between reprogramming and the coordination of cellular processes is largely unexplored.

NF-κB regulates mesenchymal transition for the induction of non-small cell lung cancer initiating cells.

The epithelial-to-mesenchymal transition (EMT) is a de-differentiation process that has been implicated in metastasis and the generation of cancer initiating cells (CICs) in solid tumors. To examine EMT in non-small cell lung cancer (NSCLC), we utilized a three dimensional (3D) cell culture system in which cells were co-stimulated with tumor necrosis factor alpha (TNF) and transforming growth factor beta (TGFβ). NSCLC spheroid cultures display elevated expression of EMT master-switch transcription factors, TWIST1, SNAI1/Snail1, SNAI2/Slug and ZEB2/Sip1, and are highly invasive.

Modification of RelA by O-linked N-acetylglucosamine links glucose metabolism to NF-κB acetylation and transcription.

The molecular mechanisms linking glucose metabolism with active transcription remain undercharacterized in mammalian cells. Using nuclear factor-κB (NF-κB) as a glucose-responsive transcription factor, we show that cells use the hexosamine biosynthesis pathway and O-linked β-N-acetylglucosamine (O-GlcNAc) transferase (OGT) to potentiate gene expression in response to tumor necrosis factor (TNF) or etoposide. Chromatin immunoprecipitation assays demonstrate that, upon induction, OGT localizes to NF-κB-regulated promoters to enhance RelA acetylation.

Outbreak of acute renal failure in Panama in 2006: a case-control study.

Objective: In September 2006, a Panamanian physician reported an unusual number of patients with unexplained acute renal failure frequently accompanied by severe neurological dysfunction. Twelve (57%) of 21 patients had died of the illness. This paper describes the investigation into the cause of the illness and the source of the outbreak.

Identification and quantification of diethylene glycol in pharmaceuticals implicated in poisoning epidemics: an historical laboratory perspective.

Over the last several decades, mass poisonings of diethylene glycol (DEG), usually ingested as an unintended component of pharmaceutical preparations, have occurred. In order to promptly halt the rise in deaths due to ingestion of these pharmaceuticals, laboratory analysis has often been employed to identify and quantify the etiologic agent after the medications have been tentatively implicated. Over the past 15 years, the Centers for Disease Control and Prevention has been involved in identifying DEG in implicated pharmaceutical products during three poisoning epidemics that occurred in Nigeria (1990), Haiti (1995), and, most recently, in Panama (2006).

Effect of ispronicline, a neuronal nicotinic acetylcholine receptor partial agonist, in subjects with age associated memory impairment (AAMI).

Cognitive decline seen in the normal elderly is associated with selective loss of neuronal nicotinic acetylcholine receptors (nAChRs). Nicotine given either by inhalation or transdermally helps cognition, but unacceptable side effects limit its utility. The present study assessed the safety, tolerability and effect on cognition of ispronicline, a highly selective partial agonist at the 4beta2 nAChR, in elderly subjects (n =76) with age associated memory impairment (AAMI).

In vivo autoradiography of [3H]SCH 39166 in rat brain: selective displacement by D1/D5 antagonists.

The purpose of this study was to examine the receptor occupancy of D1/D5 antagonists for D1-like dopamine receptors in rat brain using [3H]SCH 39166, a highly selective D1/D5 antagonist with low affinity for 5HT2 receptors. A single concentration of triated SCH 39166 was administered to rats, with or without competing doses of the Dl/D5 antagonist SCH 23390 and unlabeled SCH 39166. the D2-like antagonists haloperidol or the 5-HT, antagonist ketanserin.

Felbamate increases [3H]glycine binding in rat brain and sections of human postmortem brain.

The anticonvulsant compound felbamate (2-phenyl-1,3-propanediol dicarbamate; FBM) appears to inhibit the function of the N-methyl-D-aspartate (NMDA) receptor complex through an interaction with the strychnine-insensitive glycine recognition site. Since we have demonstrated previously that FBM inhibits the binding of [3H]5, 7-dichlorokynurenic acid (DCKA), a competitive antagonist at the glycine site, we assessed the ability of FBM to modulate the binding of an agonist, [3H]glycine, to rat forebrain membranes and human brain sections. In contrast to its ability to inhibit [3H]5,7-DCKA binding, FBM increased [3H]glycine binding (20 nM; EC50 = 485 microM; Emax = 211% of control; nH = 1.

Lack of long-term changes in cocaine and monoamine concentrations in rat CNS following chronic administration of cocaine.

In previous studies, we reported time-dependent and dose-dependent changes in the rat dopaminergic receptor system following chronic administration of cocaine. The aim of the present investigation was to monitor the concentration of monoamines (using HPLC-ECD) and cocaine (using GC-PCI/MS) in rat CNS following a dose schedule of 5, 10, 15, 20 and 25 mg/kg, i.p.

Time dependent changes in DA uptake sites, D1 and D2 receptor binding and mRNA after 6-OHDA lesions of the medial forebrain bundle in the rat brain.

Quantitative receptor autoradiography and in situ hybridization techniques were used to examine the temporal pattern of changes in dopamine uptake sites, D1 and D2 receptors and their transcripts in the striata of animals lesioned with 6-hydroxydopamine. Animals were unilaterally lesioned in the medial forebrain bundle and the brains were analyzed at 1, 2, 4, 6, 8, and 16 weeks postlesion. Degeneration of the nigrostriatal pathway induced a significant loss of dopamine uptake sites in the ipsilateral caudate putamen of all lesioned animals.

Interaction of felbamate with [3H]DCKA-labeled strychnine-insensitive glycine receptors in human postmortem brain.

The dicarbamate felbamate has been shown to be capable of competing for the binding of 5,7-[3H]dichlorokynurenic acid ([3H]DCKA) to strychnine-insensitive glycine receptors in sections of human postmortem brain. The IC50 for this interaction was 305.8 microM and the inhibition was complete at 1 mM.

Receptor alterations in subcortical structures after bilateral middle cerebral artery infarction of the cerebral cortex.

Ischemic damage to the prefrontal, motor, and somatosensory cortex induces alterations in the receptor systems of the caudate putamen and some subcortical brain regions. These alterations may represent an attempt of various neuronal systems to compensate for the reduction in innervation caused by the cortical infarction. Assessment of the receptor changes induced by cortical infarction define neuropharmacologic correlates of cortical damage, indicate possible neurotransmitters associated with neuroanatomically defined subcortical pathways, and suggest possible pharmacologic interventions to counteract the consequences of stroke.

Dopamine deficiency in a genetic mouse model of Lesch-Nyhan disease.

We have examined several aspects of neurotransmitter function in the brains of mice carrying a deletion mutation in the gene encoding the purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT). During the first 6 weeks of postnatal development, dopamine levels in whole-brain extracts from the mutant mice (HPRT-) failed to increase at rates comparable to normal animals, resulting in 40% lower dopamine levels throughout adulthood. Regional analysis in adult animals showed the caudoputamen to be the most severely affected region, with dopamine deficits of 48-64%.

Use of [3H]5,7 dichlorokynurenic acid to identify strychnine-insensitive glycine receptors in human postmortem brain.

[3H]5,7 Dichlorokynurenic acid ([3H]DCKA) was used to define conditions for obtaining selective binding to strychnine-insensitive glycine receptors. The parameters were established in sections of human brain prior to localizing the receptors sites by autoradiography. The binding of [3H]DCKA was of high affinity (Kd = 14.

A sensitive and rapid HPLC-ECD method for the simultaneous analysis of norepinephrine, dopamine, serotonin and their primary metabolites in brain tissue.

This report details a very sensitive, rapid and accurate ion-pair HPLC-ECD method for the analysis of biogenic amines and their metabolites in brain tissue. The method described enables detection of picogram amounts of 3-methoxy-4-hydroxy phenethyleneglycol (MHPG) (37 pg), 3,4-dihydroxy phenylacetic acid (DOPAC) (18 pg), norepinephrine (NE) (12 pg), epinephrine (E) (6 pg), 5-hydroxyindoleacetic acid (5-HIAA) (18 pg), 3,4-dihydroxyphenylethylamine (DA) (6 pg), 3-methoxy-4-hydroxyphenylacetic acid (HVA) (12 pg) and 5-hydroxytryptamine (5-HT) (12 pg). The linearity of the method is from 18.

Reduction in striatal D2 dopamine receptor mRNA and binding following AF64A lesions.

Unilateral lesions by a cholinotoxin, receptor autoradiography, and in situ hybridization techniques were employed to determine if dopaminergic receptors are located on cholinergic interneurons in the caudate-putamen (CPu). Lesion of the CPu with small amounts of the cholinotoxin AF64A resulted in a significant decrease in D2 receptor mRNA and D2 receptor binding. The loss was more pronounced in lateral and central portions of the CPu.

Alterations in the dopaminergic receptor system after chronic administration of cocaine.

Several studies suggest that one of the most important factors contributing to cocaine dependence is an alteration in the actions of the neurotransmitter dopamine in the central nervous system. In order to understand some of the neuroreceptor consequences of cocaine administration, groups of rats were injected with cocaine (2 daily doses of 15 mg/kg) for 1 to 21 days. Binding of [3H]cocaine, [3H]SCH23390, [3H]raclopride, and [3H]BTCP in striatal and cortical tissue from the treated animals was compared to controls.

Characterization of the binding and comparison of the distribution of benzodiazepine receptors labeled with [3H]diazepam and [3H]alprazolam.

The binding characteristics of [3H]diazepam and [3H]alprazolam were obtained by in vitro analysis of sections of rat brain. Dissociation, association, and saturation analyses were performed to optimize the conditions for obtaining selective labeling of benzodiazepine receptors with the two tritiated compounds. Both drugs approached equilibrium rapidly in vitro.

The challenging experience of palliative care support-team nursing.

The purpose of this study was to document the experience of palliative care nursing as a part of a multidisciplinary support team. Data were obtained from two palliative care support-team nurses. Each nurse privately recorded on audiotape any reflections about particularly meaningful aspects of her daily work experience; in-depth interviews with the two nurses together also were used for data collection.