Activation of a retroviral membrane fusion protein: soluble receptor-induced liposome binding of the ALSV envelope glycoprotein

Cellular aspects of remodeling in intact arteries have not been fully investigated, mainly due to the lack of an appropriate methodology that allows for simple measurements. The aim of this study was to develop a method based on laser scanning confocal microscopy (LSCM), compare it with previous methodology, and apply it to the study of remodeling in hypertension. The morphology of mesenteric resistance arteries from stroke-prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto rats (WKY) was determined with wire myography on one segment with a standardized diameter setting (0.9[d100]) and with perfusion myography on a second segment from the same artery at the calculated equivalent pressure. The second segments were stained with the nuclear dye Hoechst 33342 (live tissue) or propidium iodide (fixed tissue) and measured with LSCM and MetaMorph software. Compared with wire myography, perfusion myography showed similar differences from those previously reported. Compared with LSCM, perfusion myography showed a similar lumen but significantly smaller wall thickness in both live and fixed tissue, probably due to measurement underestimation. In the study with LSCM, arteries from SHRSP compared with those from WKY showed (1) reduced lumen, (2) altered cell density that was significantly increased in the adventitia, decreased in the media, and unchanged in the intima, (3) significantly increased medial volume, (4) significantly smaller endothelial cell nuclei, and (5) adventitial-like cells in the media. We conclude that (1) LSCM is a reliable and straightforward method to study morphology in intact vessels, (2) it provides new information on the cellular changes in remodeling, (3) adventitia might play an active role in the process of remodeling in hypertension, and (4) endothelium "remodels" in hypertension.     

Bilateral posteroventral pallidotomy in advanced Parkinson's disease in three patients

In this report, we describe the effect of staged bilateral posteroventral pallidotomy in three patients with advanced Parkinson's disease who were all of the young-onset type. Two patients had developed response fluctuations after the use of levodopa, with severe hypokinesia, painful dystonia, and rigidity in the "off" phase and violent dyskinesias in the "on" phase. One patient, in a continuous hypokinetic rigid state, was totally unresponsive to dopaminergic medication. All were at Hoehn and Yahr stage 5 in the "off" phase before surgery. After surgery, the hypokinetic state was reversed and dyskinesias were abolished in all patients. Hoehn and Yahr stages were 3 in the "off" phase postoperatively. Overall functional improvement was marked and lasting after follow-up for 7, 12, and 13 months, respectively. Complications were visual field deficit and transient central facial paresis, both in the same patient. Bilateral posteroventral pallidotomy can ameliorate response fluctuations, hypokinesia, rigidity, and painful dystonia in advanced Parkinson's disease.     

Medical use of recreational drugs by AIDS patients

A survey of 72 patients at an AIDS clinic regarding self-medication with recreational drugs for medical or psychological conditions related to their illness disclosed that marijuana was the primary drug used. The perceived benefit was for gastrointestinal conditions such as nausea, vomiting, indigestion and appetite improvement. Use of other "recreational" drugs as self-medication was reported to usually be ineffective or to worsen the condition they sought to help. Fifty-eight percent of patients reported some attempt to self-medicate. Thirty-two percent were currently using marijuana, and most admitted to pre-AIDS marijuana use. Fifty-seven percent of the sample reported some pre-AIDS drug use, primarily alcohol and marijuana. Results are discussed in terms of potential clinical problems arising from continued recreational drug use among AIDS patients.     

Chromosomal instability and its relationship to other end points of genomic instability

Chromosomal destabilization is one end point of the more general phenomenon of genomic instability. We previously established that chromosomal instability can manifest in clones derived from single progenitor cells several generations after X-irradiation. To understand the potential relationship between chromosomal destabilization and the other end points of genomic instability, we generated a series of chromosomally stable and unstable clones by exposure to X-rays. All clones were derived from the human-hamster hybrid line GM10115, which contains a single copy of human chromosome 4 in a background of 20-24 hamster chromosomes. These clones were then subjected to a series of assays to determine whether chromosomal instability is associated with a general "mutator phenotype" and whether it modulates other end points of genomic instability. Thus, we analyzed clones for sister chromatid exchange, delayed reproductive cell death, delayed mutation, mismatch repair, and delayed gene amplification. Statistical analyses performed on each group of chromosomally stable and unstable clones indicated that, although individual clones within each group were significantly different from unirradiated clones for many of the end points, there was no significant correlation between chromosomal instability and sister chromatid exchange, delayed mutation, and mismatch repair. Delayed gene amplification was found to be marginally correlated to chromosomal instability (P < 0.1), and delayed reproductive cell death (the persistent reduction in plating efficiency after irradiation) was found to be significantly correlated (P < 0.05). These correlations may be explained by chromosomal destabilization, which can mediate gene amplification and can result in cellular lethality. These data implicate multiple molecular and genetic pathways leading to different manifestations of genomic instability in GM10115 cells surviving exposure to DNA-damaging agents.     

Landing the right job: it's all in the interview

"... And What About You?" is a regular column in Advanced Practice Nursing Quarterly featuring multiple facets of personal and career development. This column will provide tools and strategies to support the continual learning that is vital for self-management of one's personal growth and career development.     

Repair of unilateral cleft lip: a comparison of five techniques

Repair of unilateral cleft lip is a challenging procedure with no single technique satisfactory for all types of unilateral cleft deformity. This study compares retrospectively five techniques of unilateral cleft lip repair in 72 children (45 boys, 27 girls). Twenty-two children had a Millard rotation-advancement repair, 5 children had a Davies Z-plasty, 22 had a modified Z-plasty, 10 had a Tennison-Randall triangular flap repair, and 13 had a Nakajima-Yoshimura straight-line repair. Assessment was performed clinically by a plastic surgeon not involved in the original surgery. Repairs were assessed objectively by measurement of the vertical length of both the repaired and normal sides of the lip with calipers. Subjective criteria used to evaluate the repair were the symmetry of Cupid's bow, the quality of scar, the alignment of white roll, the evenness of the vermilion, and the lip pout. The mean follow-up period was 5.4 years (range, 9 months-29 years). Sixty-five of the 72 repairs measured (90%) were within two standard deviations (SDs) of normal and thus were considered to be of "acceptable" length. Seven repairs were unacceptably short (>2 SDs) on measurement, six of which included a rotation-advancement repair for a complete cleft lip. Subjective results paralleled the objective results. The outcome following repair of unilateral cleft lip was similar for all five surgical methods assessed except for complete cleft lips repaired by the rotation-advancement technique, which tended to result in an unacceptably short lip as measured on the repaired side.     

The relation of ERP components to complex memory processing

The relation between various ERP components generated during encoding of a word and its subsequent recall were investigated using a "rote" serial-order and an "elaborative" category memory task. Words (flashed separately) were time-locked to EEG recordings from 21 cortical sites. ERP components from the five subjects having the highest recall scores were compared to the five lowest scoring subjects. Results based on the P200 peak amplitude data as well as the N400 and late positive component peak amplitude and latency data suggest that anterior and posterior distributional differences are elicited during encoding of words for rote and elaborative memory tasks. Furthermore, strong individual differences in these patterns were found as a function of task. A tentative argument was made that the obtained anterior and posterior differences may index different word feature selection and encoding processes, which are differentially utilized by high and low recallers.     

Attention-deficit hyperactivity symptomatology after traumatic brain injury: a prospective study

OBJECTIVE: To study prospectively the course of attention-deficit hyperactivity (ADH) symptomatology in children and adolescents after traumatic brain injury (TBI). It was hypothesized that ADH symptomatology would be significantly related to severity of injury. METHOD: Subjects were children (n = 50) aged 6 to 14 years at the time they were hospitalized after TBI. The study used a prospective follow-up design. Assessments of preinjury psychiatric, behavioral, socioeconomic, family functioning, and family psychiatric history status were conducted. Severity of injury was assessed by standard clinical scales, and neuroimaging was analyzed. RESULTS: The main finding of this study was that change in ADH symptomatology in the first 2 years after TBI in children and adolescents was significantly related to severity of injury. Overall ADH symptomatology during the study was significantly related to a measure of family dysfunction when family psychiatric history, socioeconomic status, and severity of injury were controlled. CONCLUSION: The presence of a positive "dose-response" relationship between severity of injury and change in ADH symptoms, present from the 3-month assessment, was consistent with an effect directly related to brain damage.