Use of a newly developed delivery device for percutaneous introduction of multiple lead configurations for spinal cord stimulation.

OBJECTIVE: The Epiducer lead delivery system is a novel lead delivery device that can be used to percutaneously implant S-Series paddle leads (St. Jude Medical, Plano, TX, USA) as well as multiple percutaneous leads obviating the need for laminectomy and/or multiple needle sticks, respectively. This study evaluates the safety and usage of the Epiducer lead delivery system. METHODS: An Institutional Review Board-approved observational data collection study was conducted to evaluate usage patterns of the Epiducer system. In addition to the number and frequency of different lead configurations, the following procedural aspects of the surgery were recorded during the evaluation: angle of entry, distance from entry to final lead placement, and physician feedback. Descriptive statistics on adverse events, procedural aspects, and patient outcomes were compiled. RESULTS: Data were collected from 163 patients across 25 investigational sites. Physicians successfully implanted patients using the Epiducer during 89% of the procedures. Seven possible lead configurations were implanted. There were 96% and 92% of physicians "satisfied" or "very satisfied" with accessing the epidural space and placing multiple leads with the Epiducer delivery system, respectfully. Eighty-nine percent of physicians were "satisfied" or "very satisfied" with implanting an S-Series paddle lead using the Epiducer delivery system. Ninety-five percent of physicians were "satisfied" or "very satisfied" with the Epiducer delivery system overall. Ten patients (6%) experienced adverse events. CONCLUSION: Results suggest that the Epiducer delivery system allows for the safe and successful percutaneous implantation of paddle leads and/or multiple lead configurations. Furthermore, physicians are satisfied with the Epiducer delivery system.

Outcomes of Arteriovenous Fistula Formation in an Octogenarian Population

Given the ultimate lower usage rate of the AVF and higher intervention rate within 12 months of creation, AVF formation in octogenarian patients may not be appropriate. Patient selection is vital and alternative renal access should be considered especially for those patients with risk factors associated with failure.

Understanding living clathrin-coated pits.

Most knowledge of clathrin-mediated endocytosis has been gained by biochemical fractionation and in vitro assays. Recently, the study of endocytosis has extended into the living cell. The tracking of individual clathrin-coated pits and vesicles (CCPs and CCVs) has provided new insight into understanding the dynamic nature of CCPs. The use of total internal reflection fluorescence microscopy (TIR-FM), also termed evanescent field microscopy, has enabled the direct observation of events occurring within a restricted area of the cell adjacent to and including the adherent plasma membrane. TIR-FM is now actively being pursued in the study of endocytic processes. The direct observation of CCP-associated proteins including clathrin itself, dynamin and, most recently, AP-2 has considerably challenged old models, confirming some points but raising very interesting new questions.

Homochirality as the signature of life: the SETH Cigar.

A characteristic hallmark of life is its homochirality: all biomolecules are usually of one hand, e.g. on Earth life uses only L-amino acids for protein synthesis and not their D mirror images. It is therefore suggested that a search for extra-terrestrial life can be approached as a Search for Extra-Terrestrial Homochirality (SETH). A novel miniaturized space polarimeter, called the SETH Cigar, is described which could he used to detect optical rotation as the homochiral signature of life on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. It is believed that homochirality will be found in the subsurface layers on Mars as a relic of extinct life.

Interactive computer system for tuning the cochlear 22-channel implant in young children.

A computer system has been developed that has a games computer and a vibrotactile device linked into the Cochlear Diagnostic and Programming System. It uses a child's response to a computer game as a way of eliciting initial electrical thresholds and of maintaining attention, so that a large number of thresholds may be measured in a single session. Results have given times of 15 and 35 minutes for initial programming of all 22 electrodes in two 4-year-olds, and the system has been found to be useful in children from 3 years to early teens.

Multivariate analyses of elemental hair concentrations from a medieval Nubian population.

Elemental hair concentrations were obtained from 168 mummified individuals recovered during excavations of cementeries S and R (A.D. 550-1450), at Kulubnarti, Republic of the Sudan (Van Gerven et al., 1981). Concentrations of calcium (Ca), magnesium (Mg), strontium (Sr), manganese (Mn), zinc (Zn), iron (Fe), and copper (Cu) were determined using inductively coupled plasma emission spectrometry (ICP) (Sandford, 1984; Sandford et al., 1983). Following univariate statistical reanalyses of these data (Sandford and Kissling, 1993a, b), we applied principal component analysis and multidimensional scaling to clarify their multivariate structure. Similar underlying associations were revealed in the two cemeteries. The first principal component, consisting of Mg, Ca, Sr, and Mn, may reflect inherent chemical similarities coupled with specific dietary factors (e.g., vegetation intakes) and physiological processes (e.g., bone remodeling). The second principal component, a contrast between Fe and Zn, may be due to their competitive relationship during absorption. The third principal component consists of Cu alone (in cemetery S), and Cu and Fe (in cemetery R), suggesting utilization of animal protein and an underlying synergism between Cu and Fe, respectively. Multidimensional scaling substantiates a three-dimensional model for describing elemental covariation. While interpretation of the first two dimensions was analogous to those of the first two principal components, the third dimension may represent antagonism between pairs of elements during absorption, transport and/or utilization (cemetery R: Cu vs. Zn; cemetery S: Cu vs. Zn, Fe vs. Mn). While these results provide the most persuasive evidence to date that elemental hair concentrations from this population reflect chiefly biogenic processes, isolation of diagenetic and exogenous effects requires further investigation through controlled studies.

Neural tube defect etiology: new evidence concerning maternal hyperthermia, health and diet.

The authors conducted a retrospective case-control study to determine risk factors for neural tube defects (NTD). 88 Louisiana women (44 matched pairs) were interviewed. Previous evidence suggested that maternal health and/or nutrition may be involved in the etiology of NTD. The findings substantiate the importance of maternal risk factors, including the apparent elevation of body temperature from taking hot baths during the first gestational month. Maternal health, as measured by reported illness and use of medications during pregnancy, was also significant. Several dietary factors, including intake of foods high in beta carotene, appeared to confer a protective effect. These findings suggest that some risk factors, particularly those involving maternal nutrition, may be population-specific.

Structure-activity studies of trichothecenes: cytotoxicity of analogues and reaction products derived from T-2 toxin and neosolaniol.

Forty-two analogues and reaction products derived from T-2 toxin or neosolaniol were assayed for their cytotoxicity to cultured mouse lymphoma cells. Structure-activity relationships confirmed the stereospecific nature of the cytotoxic action of T-2. Cytotoxicity was particularly susceptible to changes at C3, C4, C9, and C10 but was relatively unaffected by changes at C8, which appears to represent a region of steric tolerance in the interaction of T-2 with a cellular constituent. The most potent compounds were T-2, diacetoxyscirpenol, and a series of C8 ester analogues 11 and 31-35.

Decrement in "social stress" among wild rattus rattus treated with antibiotic.

"Black" rats, Rattus rattus, were trapped and studied in colonies of 6 adult males and 6 adult females. Eight colonies had antibiotic (Neoterramycin) in their drinking water, and eight (controls) had not. Twenty mated pairs were kept in small cages; of these, ten received Neoterramycin. The only deaths of males were in the control colonies. In the antibiotic colonies there were also (1) a lower incidence of attack when behavior was directly observed, (2) less skin wounding, (3) less macroscopic evidence of lung lesions. The lowest incidence of skin scars and lung lesions was among the rats kept in small cages. There was no evidence of an effect of the antibiotic on body or adrenal weights, or on kidney pathology. The locomotor activity of rats was separately recorded, with or without antibiotic, in artificial automated environments There was no evidence that activity was reduced by antibiotic. It is hypothesized that diseased rats provoke more attack than healthy ones.