Psychological dread and extreme persistent fear

Psychological dread is a phenomenon with which virtually everyone is familiar, whether dreading a medical appointment, a job interview, or the impending death of a loved one. Despite the prevalence of dread in most people's everyday lives, surprisingly little empirical research has explored the construct. The purpose of the current research was to examine psychological dread (Study 1 and Study 2) and to compare dread to extreme persistent fear (Study 2). Respondents across both studies completed surveys on which they described a dreaded experience (Studies 1 and 2) or an extremely feared event (Study 2) and answered questions about the event. Participants reported uncertainty and lack of control surrounding events associated with both dread and extreme persistent fear. They also anticipated that they would feel relief when these events were over, but this relief was greater with dread than fear. Implications for coping with dread and extreme persistent fears are discussed along with comparisons of the types of events most commonly associated with dread and extreme fear.

Delivery of proteins to CNS as seen and measured by positron emission tomography

Presently, there are no effective treatments for several diseases involving the central nervous system (CNS). While several novel molecular approaches are being developed, many of them require delivery of macromolecular or supramolecular agents to the CNS tissues protected by the blood-brain and blood-arachnoid barriers. A variety of approaches that are being developed for overcoming or bypassing the barriers are based on complex transfer processes. The delivery of biopharmaceuticals and other macromolecules and particulates to the CNS, especially through the leptomeningeal (intrathecal) route, includes a variety of stages, such as leptomeningeal propagation, drainage to the systemic circulation, and penetration into the CNS. The investigation of complex pharmacokinetics that includes convective, as well as diffusional and active transfer processes, greatly benefit from real-time non-invasive in vivo monitoring of the drug transport. Pharmacological positron emission tomography (PET) imaging, which enables such monitoring, plays an increasingly significant role in drug delivery and biopharmacology. PET is a powerful tool for quantitative in vivo tracking of molecules labeled with positron-emitting radionuclides. The high sensitivity, format, and accuracy of the data (similar to those of conventional tissue sampling biodistribution studies) make PET a readily adoptable pharmacological technique. In contrast to the conventional studies, PET also allows for longitudinal nonterminal same-animal studies. The latter may not only improve the data statistics, but also enable preclinical studies (especially in large and/or rare animals) not feasible under the conventional approach. This paper is intended to demonstrate the character of data that can be obtained by PET and to demonstrate how the main patterns of the leptomeningeal route pharmacokinetics can be investigated using this method. Examples of data processing are taken from our recent studies of five model proteins in rats and nonhuman primates.

Positional cloning of a quantitative trait locus contributing to pain sensitivity: possible mediation by Tyrp1

To identify novel pain-relevant genes, a set of 35 recombinant congenic strains derived from the sensitive C57BL/6 and resistant A/J strains were tested for their sensitivity to noxious heat on the radiant heat paw-withdrawal test. Nine strains were found to display differential sensitivity, and the two most extreme responders were used to generate independent secondary crosses for quantitative trait locus (QTL) mapping. From these genetic analyses, a QTL, which we call Tpnr5, was mapped to a 14-Mb interval of mouse chromosome 4 containing 39 genes. In addition to the paw-withdrawal test phenotype, Tpnr5 may be relevant to mechanical and inflammatory nociception. A series of strategies - including in silico analyses, reverse transcriptase polymerase chain reaction (RT-PCR) in multiple tissues and exonic DNA sequencing - were used to generate a list of six prioritized candidate genes. One of these, tyrosinase-related protein 1 (Tyrp1), displayed enriched expression in the dorsal root ganglia, an inactivating (C110Y) mutation in the resistant A/J strain, and a null mutant found to be more resistant to thermal nociception compared to its wild-type counterpart. Although other genes cannot be definitively ruled out, existing data are supportive of the candidacy of Tyrp1 as representing the Tpnr5 QTL. Tyrosinase-related protein 1 is the rate-limiting enzyme in the production of eumelanin, and possible relationships between eumelanin-expressing cells and thermal nociception are discussed. The positional cloning of Tpnr5 is also considered in light of the heuristic value but continuing challenges of QTL mapping in the mouse.

[Destruction of a penile urethra resulting from a snake bite: Uretroplasty using inguinal flap of Mac Gregor]

Following a snake bite to the penis, a 69 years old man presented a large defect of hemicircumferential ventral penis, destroying the penile urethra along its entire length exposing the erectile bodies. The authors proposed a two-stage reconstruction of the urethra with an inguinal axial pedicle flap of Mac Gregor. This well-vascularized flap thick after degreasing helped repair the penile urethra along its entire length and make up losses of substance with a good functional and aesthetic result.

Rapid DNA quantification method in microplates using daunorubicine fluorescence quenching

We have developed a rapid, sensitive and inexpensive method to quantify DNA in crude extracts or PCR reaction products using daunorubicine fluorescence quenching. We obtained a linear standard curve from 4.7 ng to 600 ng DNA and no interaction was observed in the presence of proteins.

Cardiovascular and testosterone responses to contested dominance in women

Examined cardiovascular and testosterone responses of dominant and submissive women to an acute stressor involving contested dominance. Twenty (10 dominant, 10 submissive) university students rated their dominance to a predefined reference group, participated in a task that involved debating with a trained technician, and were continuously provided with bogus feedback throughout the task concerning biochemical substances in their blood that purportedly covaried with dominance. Covariance analyses revealed that dominant women were much more reactive to the stressor in several cardiovascular parameters than those classified as submissive. Serum testosterone did not vary as a function of the experimental manipulation, and at each measurement point, dominant and submissive subjects had essentially identical serum levels of this hormone. Interestingly, however, baseline testosterone for the dominant group was related to changes in systolic blood pressure (i.e., gain scores computed as task response minus baseline values).

Acute stress reactivity from contested dominance in dominant and submissive males

We examined the cardiovascular and testosterone responses of dominant and submissive males to an interpersonal challenge of dominance status. Twenty college-aged students rated their dominance to predefined reference groups and engaged in a debate against a trained technician. Throughout the task, they were continuously given false feedback regarding biochemical substances in the plasma that purportedly covaried with dominance. Covariance analyses revealed that the task created greater heart rate reactivity and lower testosterone levels on the part of submissive subjects when contrasted with those scoring high in self-reported dominance. Interpretation of these data emphasizes the importance of an interactionist perspective in research dealing with acute stress reactivity.