Effects of Climate on the Variation in Abundance of Three Tick Species in Illinois.

The range of ticks in North America has been steadily increasing likely, in part, due to climate change. Along with it, there has been a rise in cases of tick-borne disease. Among those medically important tick species of particular concern are Ixodes scapularis Say (Acari: Ixodidae), Dermacentor variabilis Say (Acari: Ixodidae), and Amblyomma americanum Linneaus (Acari: Ixodidae). The aim of this study was to determine if climate factors explain existing differences in abundance of the three aforementioned tick species between two climatically different regions of Illinois (Central and Southern), and if climate variables impact each species differently. We used both zero-inflated regression approaches and Bayesian network analyses to assess relationships among environmental variables and tick abundance. Results suggested that the maximum average temperature and total precipitation are associated with differential impact on species abundance and that this difference varied by region. Results also reinforced a differential level of resistance to desiccation among these tick species. Our findings help to further define risk periods of tick exposure for the general public, and reinforce the importance of responding to each tick species differently.

[Theoretical reflection on the place of memory and temporal cognitive mechanisms in addictive disorders]. / Réflexion théorique sur la place des mécanismes cognitifs mnésiques et temporels dans l'addiction.

INTRODUCTION: Addictions can be regarded as cognitive disorders related to neurobiological impairments. On the one hand, some cognitive impairments occur as a result of substance intake and withdrawal upon stopping intake, while, on the other hand, cognitive mechanisms are responsible for initiating and maintaining addiction. In this review, we detail the memory and temporal mechanisms involved in this pathology. METHODOLOGY: We reviewed the literature dedicated to the mechanisms of conditioning association between a substance and a context, and the memory and temporal mechanisms involved in the maintenance of addiction. Cognitive impairments in this context are accompanied by both short-term and long-term neurobiological disorders. RESULTS: Drug-context conditioning is dependent on learning abilities in rats and humans, and it is the first step towards the development of an addiction. In fact, with the beginning of an addiction, it is the context associated with the substance intake, which determines the reinforcing factors (such as pleasure in the case of drug consumption) for the development of an addiction. Maintenance of addiction is related to the persistence of this association between context and substance. Furthermore, the impulsiveness of patients renders them unable to delay their gratification. Consequently, even if delayed gratifications are more valuable, patients prefer immediate gratification such as substance use. DISCUSSION: The memory and temporal mechanisms of addiction are central to the initiation and maintenance of drug addiction. They also affect patients' ability to develop projects for the future. The salience of the memory association between drug and context is accompanied by a decline in autobiographical memories, which become poor and lacking in detail. It is probably these impairments which are responsible for the difficulty that the patients have while investigating their story during psychotherapy. On the other hand, given that even though delayed gratification is greater patients prefer immediate gratification, they have difficulty making plans for the future and constructing their own personality. These cognitive impairments are sustained by neurobiological correlates such as dopamine dysregulation in the short-term and changes in neural plasticity in the cortico-meso-limbic system in the long term. CONCLUSION: We reviewed full arguments which highlight that addiction is mediated by cognitive mechanisms which are related on the one hand to clinical symptoms and, on the other hand, to neurobiological alterations. According to the literature, memory and time mechanisms seem to be central to the initiation and maintenance of addictive behaviours. More research is needed to improve our knowledge of the cognitive mechanisms of addiction and to develop new tools for treating patients.

FOXA1 and IRF-1 intermediary transcriptional regulators of PPARgamma-induced urothelial cytodifferentiation.

The peroxisome proliferator-activated receptor gamma (PPARgamma) is a ligand-activated transcription factor that has been implicated in the induction of differentiation of various cell types, including human uroepithelial cells. PPARgamma-mediated differentiation of normal human urothelial (NHU) cells in vitro requires coinhibition of epidermal growth factor receptor (EGFR) signalling and is characterised by de novo expression of late/terminal differentiation-associated genes, including uroplakins (UPK), over a 6-day period. We used gene microarrays to identify intermediary transcription factors induced in direct response to PPARgamma activation of EGFR-inhibited NHU cells. FOXA1 and IRF-1 contained consensus cognate binding sites in UPK1a, UPK2, and UPK3a promoters and transcripts were induced within 12 h of PPARgamma activation; transcription complex formation was confirmed by electromobility shift assays. In urothelium in situ, both FOXA1 and IRF-1 were nuclear and expressed in a differentiation-associated pattern. Knockdown by transient siRNA of either FOXA1 or IRF-1 abrogated PPARgamma-induced uroplakin expression in vitro. This is the first evidence that ligand activation of PPARgamma induces expression of intermediary transcription factors that mediate an epithelial differentiation programme and represents a new paradigm for understanding differentiation, regenerative repair and inflammation in epithelial tissues.

Pre prosthetic mobility: the amputees' perspectives.

PURPOSE: It is considered good practice that amputees remain in a wheelchair until fitted with a prosthesis. However, this practice is not evidence based. In the first of a series of studies in pre prosthetic mobility, this study will explore the individual amputees' perspective. METHOD: A total of 25 participants from a regional disablement service centre were interviewed focusing on their experiences of getting around the home post discharge. The transcripts were coded for types of mobility methods used and the content analysed. RESULTS: Whilst the wheelchair was the predominant method of mobilizing, this was not viewed positively by amputees. Crutches were frequently used, even if crutches were not provided by therapists. Participants cited space and choice as reasons behind this, in particular the psychological impact of being 'stuck' in a wheelchair. Other methods cited included crawling and bottom shuffling. CONCLUSION: Amputees do not always comply with therapists' advice and frequently use other methods of mobilizing as a matter of choice as well as necessity. The risk factors associated with these methods is a priority for future research.

Effects of the amnesic drug lorazepam on complete and partial information retrieval and monitoring accuracy.

RATIONALE: In Koriat's accessibility model (Koriat, Psychol Rev, 100:609-639, 1993; Koriat, J Exp Psychol Gen, 124:311-333, 1995), when a person fails to recall a required target, he or she can nevertheless provide some partial information about the target. Moreover, individuals are able to provide feeling-of-knowing (FOK) judgments about the availability of the target in memory. The cues for the FOK evaluations reside in the products of the retrieval process itself. It was shown that the benzodiazepine lorazepam drug induces some impairment of memory. OBJECTIVES: The effects of the amnesic benzodiazepine lorazepam on the total and partial recall of recently learned material and on FOK ratings were investigated in healthy volunteers. METHODS: Twenty-eight healthy volunteers participated in the study: 14 of these received a capsule containing lorazepam (0.038 mg/kg) and 14 a placebo capsule. The material to be learned consisted of four-letter nonsense tetragrams with each letter providing partial information with regard to the four-letter target (Koriat, Psychol Rev, 100:609-639, 1993). RESULTS: The number of incorrect letters reported was higher for the lorazepam than for the placebo condition. The FOK magnitude was higher for the placebo participants than for the lorazepam participants. The predictive value of FOK for recognition was preserved by the drug. CONCLUSION: When studying four-letter nonsense letter strings, lorazepam participants present an impairment of episodic short-term memory and the drug has an effect on FOK estimates but not on the predictive accuracy of the FOK. The accessibility hypothesis of FOK was confirmed in this study and seems to retain some validity even under the effect of an amnesic drug.

Defective relationship between subjective experience and behavior in schizophrenia.

OBJECTIVE: The relationship between subjective experience and behavior abnormalities in schizophrenia was investigated. METHOD: Eighteen patients with schizophrenia and 18 normal comparison subjects completed a general knowledge task with two incentive conditions to measure monitoring effectiveness, control sensitivity, and response criterion setting. RESULTS: The patients' levels of monitoring effectiveness and control sensitivity were lower than those of the comparison subjects. The effect of incentives on response criterion values was similar in the two groups. CONCLUSIONS: Patients were impaired in subjectively assessing the correctness of their knowledge, and their behavior was less determined by subjective experience than that of normal subjects. The patients' intact sensitivity to incentives has implications for cognitive remediation.

Dimeric W3SO3 cluster complexes: synthesis, characterization, and potential applications as X-ray contrast agents.

Our continued research on the use of heavy metal cluster complexes as a new class of X-ray contrast agents in medical diagnostic imaging is described. A series of 2:3 cluster-ligand complexes, [(W(IV)3SO3)2L3]4- (L = linear polyaminopolycarboxylate ligands), were isolated from the reaction of aqua ion [W(IV)3SO3(H2O)9]4- (prepared in large quantities through an improved literature process) with respective ligands in refluxing DMF. The salts of [(W(IV)3SO3)2L3]4- complex anions were fully characterized using routine techniques such as elemental analysis, MS, HPLC, UV-vis, IR, and NMR. The solid structures of two complex anions, [(W(IV)3SO3)2(PDTA)3]4- and [(W(IV)3SO3)2(HO-PDTA)3]4-, were determined by X-ray crystallography. They are the first examples wherein two W(IV)3SO3 clusters are complexed and linked by three ligands that contain two terminal iminodiacetate (bis-IDA) groups. Complexation of the unstable aqua ion [W(IV)3SO3(H2O)9]4- with ligands has imparted desired biological compatibility to the tungsten metal cluster. These complexes are stable and highly soluble in H2O. The potential utility of such tungsten cluster complexes as X-ray contrast agents was evaluated in both in vitro and in vivo animal studies. In addition, the syntheses of several new linear polyaminopolycarboxylate ligands used in this study are reported.

Consciousness in schizophrenia: a metacognitive approach to semantic memory.

Recent studies have shown that schizophrenia may be a disease affecting the states of consciousness. The present study is aimed at investigating metamemory, i.e., the knowledge about one's own memory capabilities, in patients with schizophrenia. The accuracy of the Confidence level (CL) in the correctness of the answers provided during a recall phase, and the predictability of the Feeling of Knowing (FOK) when recall fails were measured using a task consisting of general information questions and assessing semantic memory. Nineteen outpatients were paired with 19 control subjects with respect to age, sex, and education. Results showed that patients with schizophrenia exhibited an impaired semantic memory. CL ratings as well as CL and FOK accuracy were not significantly different in the schizophrenic and the control groups. However, FOK ratings were significantly reduced for the patient group, and discordant FOK judgments were also observed more frequently. Such results suggest that FOK judgments are impaired in patients with schizophrenia, which confirms that schizophrenia is an illness characterized by an impaired conscious awareness of one's own knowledge.

Plasma membrane NADH oxidase of maize roots responds to gravity and imposed centrifugal forces.

NADH oxidase activities measured with excised roots of dark-grown maize (Zea mays) seedlings and with isolated plasma membrane vesicles from roots of dark-grown maize oscillated with a regular period length of 24 min and were inhibited by the synthetic auxin 2,4-dichlorophenoxyacetic [correction of dichorophenoxyacetic] acid. The activities also responded to orientation with respect to gravity and to imposed centrifugal forces. Turning the roots upside down resulted in stimulation of the activity with a lag of about 10 min. Returning the sections to the normal upright position resulted in a return to initial rates. The activity was stimulated reversibly to a maximum of about 2-fold with isolated plasma membrane vesicles, when subjected to centrifugal forces of 25 to 250 x g for 1 to 4 min duration. These findings are the first report of a gravity-responsive enzymatic activity of plant roots inhibited by auxin and potentially related to the gravity-induced growth response.

Young widows' experience with an Internet self-help group.

1. Finding empathetic support is an important factor in coping for people with various needs. 2. Support group resources may be limited due to long travel distances, expense of child care, lack of transportation, or no available group for specific needs. 3. Nurses can guide their patients to Internet support groups for self-care when traditional groups are not accessible or applicable to their circumstances.