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The age at exposure significantly affects the retention and distribution of 226Ra and 239Pu, both of which deposit in the skeleton although in somewhat different patterns. Beagles aged 2 days (neonates), 90 days (juveniles), 18 months (young adults), or 5 yrs (mature) received a single subacute injection of one of these nuclides and were sacrificed serially during a 2-yr interval. Nuclide concentrations in plasma, the skeleton, individual bones and bone sections were determined and retention equations were calculated. The microanatomical skeletal nuclide distribution was studied after fission track or conventional autoradiography. Elimination of 239Pu and its translocation from bone surfaces to the bone volume caused by bone growth and turnover processes were measured. Average radiation doses and dose rates as a function of age at exposure were determined. Initial uptake and retention, skeletal nuclide concentration, proliferative activity of local cell populations and residence time of the nuclide on skeletal surfaces were affected significantly by age at exposure. The effect of these parameters on tumor induction is discussed. This study has provided early retention and distribution data which together with data from a chronic toxicity study will be used to estimate the risk of Pu exposure relative to that of Ra to humans of all ages. [ABSTRACT FROM AUTHOR]

Objective: We aimed to determine the frequency of all known forms of congenital muscular dystrophy (CMD) in a large Australasian cohort., Methods: We screened 101 patients with CMD with a combination of immunofluorescence, Western blotting, and DNA sequencing to identify disease-associated abnormalities in glycosylated alpha-dystroglycan, collagen VI, laminin alpha2, alpha7-integrin, and selenoprotein., Results: A total of 45% of the CMD cohort were assigned to an immunofluorescent subgroup based on their abnormal staining pattern. Abnormal staining for glycosylated alpha-dystroglycan was present in 25% of patients, and approximately half of these had reduced glycosylated alpha-dystroglycan by Western blot. Sequencing of the FKRP, fukutin, POMGnT1, and POMT1 genes in all patients with abnormal alpha-dystroglycan immunofluorescence identified mutations in one patient for each of these genes and two patients had mutations in POMT2. Twelve percent of patients had abnormalities in collagen VI immunofluorescence, and we identified disease-causing COL6 mutations in eight of nine patients in whom the genes were sequenced. Laminin alpha2 deficiency accounted for only 8% of CMD. alpha7-Integrin staining was absent in 12 of 45 patients studied, and ITGA7 gene mutations were excluded in all of these patients., Conclusions: We define the distribution of different forms of congenital muscular dystrophy in a large cohort of mixed ethnicity and demonstrate the utility and limitations of current diagnostic techniques.

Approximately 9,000,000 US workers are occupationally exposed to radiofrequency (RF) radiation; over 250,000 operate RF dielectric heaters. Our purpose was to determine whether male RF heater operators experience increased adverse reproductive effects reflected in reduced semen quality or altered hormone levels. We measured incident RF heater radiation exposures and RF-induced foot currents at four companies. For 12 male heater operators and a comparison group of 34 RF-unexposed men, we measured 33 parameters of semen quality and four serum hormones. Despite wide variation in individual exposure levels, near field strengths and induced foot currents did not exceed current standard levels and guidelines. We observed minor semen quality and hormonal differences between the groups, including a slightly higher mean follicle-stimulating hormone level for exposed operators (7.6 vs 5.8 mIU/mL). Further occupational studies of RF-exposed men may be warranted.

Background: We hypothesized that single premature extrastimuli (S(2)) insufficient to induce reentry produce proarrhythmic effects (proarrhythmic preconditioning) that are measurable by use of the magnitude, phase, and temporal distribution of repolarization alternans (RPA; alternate-beat fluctuations in ECG repolarization)., Methods and Results: Before programmed electrical stimulation (PES), surface ECG leads I, aVF, and V(1) were recorded in 30 patients during simultaneous atrial and ventricular pacing at 500 ms with S(2) coupling intervals (CIs) decreasing from 400 to 240 ms in 20-ms steps. We determined RPA magnitude (V(alt)) as the 0.5-cycle/beat peak after spectral decomposition of consecutive STU intervals over 64 beats immediately preceding and following each S(2), RPA phase reversals as discontinuities in the even/odd phase of STU alternation, and RPA distribution as the time point of median RPA magnitude within repolarization. Eighteen patients were induced into ventricular tachycardia (VT), whereas 12 were not. Extrastimuli dynamically modulated each characteristic of RPA. S(2) augmented V(alt) in inducible (8.2+/-2.3 versus 6.2+/-1.6 microV; P=0.003) but not noninducible patients. S(2) reversed RPA phase more in inducible than in noninducible patients (56.7% versus 45.3%; P=0.02 by chi(2)), particularly when CI was < or =300 ms (66.3% versus 46.5%; P=0.006). Finally, S(2) redistributed RPA significantly later within repolarization in inducible patients. Each effect was more marked for CI < or =300 ms., Conclusions: A single S(2) increases RPA magnitude, reverses its phase, and redistributes it later in repolarization in patients with the substrates for VT. These effects become more pronounced with shorter coupling intervals. These results suggest that it is possible to track the dynamic proarrhythmic preconditioning of single premature depolarizations.

Thirty superficial perineal neurovascular pedicles from 15 formaldehyde-fixed female cadavers were dissected and analyzed with the purpose of establishing the anatomic basis for the design and elevation of vulvoperineal fasciocutaneous flaps based on their anatomic elements. The average internal diameter of the superficial perineal artery was 0.53 +/- 0.2 mm, determined by means of an image analysis system. Three distinct anatomic patterns of cutaneous arterial vascularization were seen bilaterally, and two types of vulvoperineal fasciocutaneous flaps are described.

Environmental dose reconstructions are being conducted at many nuclear weapons production and testing sites in the United States. These projects involve reconstructing potential radiation exposures and doses from past releases of radionuclides to people who lived near nuclear facilities where these releases occurred. The results of dose reconstructions can be used as the basis for deciding if epidemiologic studies or other public health activities should be undertaken. In addition, the results of dose reconstruction can be used in other risk assessment activities, such as those associated with environmental restoration and radioactive waste management. For example, the historical inventory of hazardous materials used and potentially released at the site can be used to begin to assess the risk for exposures from current and future activities. The site-specific environmental dosimetry methods developed for dose-reconstruction purposes are applicable to other environmental risk assessments performed for that site. These and other benefits of environmental dose reconstructions are discussed.

Background: Atrial activation during atrial fibrillation (AF) is frequently described as random or chaotic. We propose that activation during AF is constrained by the principles of reentrant excitation; that these constraints impart a measurable spatial organization to activation during AF; and that the distance over which activation sequences remain well correlated can be readily measured and related both to the propensity of AF to sustain itself as well as to atrial tissue wavelength., Methods and Results: We describe a novel signal-processing technique that quantifies the correlation in activation sequences recorded from five equally spaced sites in the right atrium in patients undergoing electrophysiology studies. In 20 patients in AF (12 with paroxysmal AF, 5 with chronic AF, and 3 with no clinical history of AF), the average correlation was 0.54 +/- 0.12 at 11 mm and 0.32 +/- 0.11 at 44 mm, compared with 0.95 +/- .023 and 0.91 +/- .023 in sinus rhythm. In AF, the correlation versus distance relation was monotonically decreasing, well fit by a decaying exponential function. The space constant of this exponential function, termed the activation space constant, provides a single objective metric of the spatial organization of activation during AF. The mean activation space constant for the group was 2.6 +/- 1.15 cm. Chronic AF had the lowest mean activation space constant (1.84 +/- 0.36 cm) and AF in patients with no prior history of AF had the highest (3.06 +/- 0.40 cm) (P < .05), with paroxysmal AF characterized by intermediate values (2.80 +/- 1.4 cm)., Conclusions: Using a novel method to measure the spatial organization of atrial activation during AF, we have demonstrated that AF in the intact human heart is organized over a length scale consistent with reentrant excitation. Preliminary results suggest a relationship between measured spatial organization and the clinical course of the arrhythmia. Further work is needed to determine whether measurement of spatial organization may be useful in prospective patient-specific selection of therapeutic options.

Sera from 44 patients with clinically suspected pulmonary aspergillosis (mainly of an allergic type) were examined for antibodies to Aspergillus fumigatus using an enzyme-linked immunosorbent assay (ELISA) and counter-immunoelectrophoresis (CIE). Of the sera, 15 were considered to contain Aspergillus antibodies using ELISA; 11 of these also contained precipitins by CIE. In no instance was a CIE-positive serum negative by ELISA. The serum of 1 patient with autopsy-verified invasive pulmonary aspergillosis was negative in both tests. Protein-enriched antigens derived by ammonium sulphate precipitation of crude hyphal homogenates seemed of most use in ELISAs. In addition, 4 of 8 sera obtained from patients with possibly invasive candidosis also revealed significant levels of Aspergillus antibody by ELISA (but not CIE). All of the 8 sera contained readily detectable Candida precipitins by CIE. Problems of potential cross-reactivity obviously need careful consideration with ELISAs. Our results suggest that ELISA procedures under appropriately controlled conditions are more sensitive than CIE for detecting Aspergillus antibodies. However it seems that some patients with invasive aspergillosis will be antibody-negative even with sensitive tests such as ELISA.

Estimates of both individual and collective doses received by the United States population following the Chernobyl accident have been made by using the data obtained from the U.S. Environmental Protection Agency's Environmental Radiation Ambient Monitoring System. Radionuclides associated with the debris first were measured in precipitation and surface air particulates at Portland, OR and Olympia, WA on 5 May 1986. Iodine-131 was the most consistently measured nuclide in all media, although several Cs and Ru isotopes also were observed. Strontium and any actinides notably were absent from the samples at the lower level of detection. The highest calculated individual-organ dose due to intake during May and June 1986 was 0.52 mSv to the infant thyroid in the state of Washington. This was predominantly (98%) from the ingestion of milk. The maximum U.S. collective dose equivalent to any organ was calculated to be 3,300 person-Sv to the thyroid. Risk estimates project three excess lung cancer deaths and an additional four deaths due to cancers of thyroid, breast and leukemia in the U.S. population over the next 45 y from exposure during the May-June 1986 interval. The only long-lived radionuclide measured in milk samples following the accident was 137Cs. We estimate 20 excess fatalities from the ingestion of 137Cs in milk during all subsequent years, with six of these due to lung cancer and the majority of the remainder distributed approximately equally among cancers of the thyroid, breast, liver and leukemia. A total of 100 excess fatalities from all dietary components was estimated. Because of the uncertainty of risk estimates from data such as those available for this study, all calculated values carry a range of uncertainty from a minimum of one-half the calculated value to a maximum of two times the calculated value. The estimated excess fatalities given above may be compared with corresponding projected cancer mortality from all other causes: 41,000 fatalities from thyroid cancer and 3,800,000 fatalities from lung cancer are estimated to occur within the U.S. population during the next 45 y.

We investigated the relationship between electrical alternans and cardiac electrical stability in a series of 20 dog experiments and in a pilot clinical study. Electrical alternans was detected in both the QRS complex and the ST-T wave by use of a novel multidimensional spectral technique. The magnitude of the alteration was expressed as the alternating electrocardiographic morphology index (AEMI), expressed as parts per million of waveform energy. Electrical stability in the dog preparations was assessed via the ventricular fibrillation threshold measurement, and in the clinical studies via programmed stimulation. In 10 dog experiments, systemic hypothermia resulted in a 60% decrease in ventricular fibrillation threshold (VFT) (p less than .0001) and a significant increase in both AEMI(QRS) form 3.7 +/- 3.0 to 1448 +/- 548 (p less than .0001) and AEMI(ST-T) from 43.9 +/- 18.4 to 19,178 +/- 5579 (p less than .0001). In 10 dog experiments, transient coronary artery ligation also resulted in a 60% decrease in VFT (p less than .0001), an increase from 76.3 +/- 46.5 to 245 +/- 11 in AEMI(QRS) (p less than .05), and an increase from 842 +/- 505 to 1365 +/- 392 in AEMI(ST-T) (p less than .002). In 119 observations in 20 animal experiments, the rank correlation between VFT and AEMI(QRS) was -.30 (p less than .001), with that between VFT and AEMI(ST-T) being -.55 (p less than .0001). In a double-blind pilot clinical trial consisting of 23 studies in 19 patients, the result of electrophysiologic testing was used as an independent measure of cardiac electrical stability. Alternation in waveform morphology identified the inducible patient population with a sensitivity of 92%, a positive predictivity of 70%, and a specificity of 50% (p less than .05). We conclude that analysis of subtle beat-to-beat variability in electrocardiographic morphology may provide a noninvasive measure of cardiac electrical stability.

During a 105 day period in mid 1984, 796 isolates of coagulase-negative staphylococci were recovered from routine specimens handled in the Microbiology Laboratory, Dunedin Hospital. Of these isolates 504 (63.3%) were from wounds, 170 (21.4%) from urines, 58 (7.3%) from intravascular catheter tips, 44 (5.5%) from blood cultures and 20 (2.5%) from sputa. Presumptive identification of 315 consecutive isolates revealed 175 (55.6% of total) strains of Staphylococcus epidermidis, 44 (14.0%) S. capitis, 36 (11.4%) S. haemolyticus/hominis, 29 (9.2%) S. warneri, 19 (6.0%) S. simulans and 12 (3.8%) members of the S. saprophyticus group. Using laboratory generated criteria, 44.8%, 25.9% and 4.5% of coagulase-negative isolates from catheter tips, urines and blood cultures respectively, were deemed pathologically potentially significant. Although more common, S. epidermidis did not appear to be significantly more virulent than other members of the epidermidis species group or S. simulans; 67% of the S. saprophyticus group isolates from urine were considered pathologically significant. Antibiograms on the 796 coagulase-negative isolates revealed 63.2% resistant to penicillin, 22.6% to methicillin, 34.8% to cephradine, 27.5% to gentamicin, and 14.4% to erythromycin; multiple resistance was common. Methicillin resistance was a feature of S. saprophyticus group strains. With isolates from catheter tips and blood cultures, a significantly higher percentage of those regarded as significant were gentamicin resistant. Apart from penicillin, antibiotic resistance was not so marked in strains of coagulase-positive staphylococci recovered over the same period.

A rare case of midline upper-lip sinus, without associated congenital anomalies, is presented. Etiopathogenesis between cleft central upper lip and central philtral sinus differ. Therefore, several theories for etiology are discussed, and a more plausible theory of epidermal burrowing and invagination is presented.

A simple, robust, high performance liquid chromatographic method for serum paracetamol determination in both the therapeutic and overdose concentration ranges is described. The within- and between-batch precision of the method was better than CV 5% at both micromolar and millimolar concentrations, and recovery of added paracetamol from drug-free serum exceeded 96%. No interference from any of the other drugs, drug metabolites, and dietary constituents tested was found. Performance data in the overdose concentration range has been compared with that from the enzymatic kit procedure, and results from the two assays showed good correlation (r = 0.97).

The age at exposure significantly affects the retention and distribution of 226Ra and 239Pu, both of which deposit in the skeleton although in somewhat different patterns. Beagles aged 2 days (neonates), 90 days (juveniles), 18 months (young adults), or 5 yrs (mature) received a single subacute injection of one of these nuclides and were sacrificed serially during a 2-yr interval. Nuclide concentrations in plasma, the skeleton, individual bones and bone sections were determined and retention equations were calculated. The microanatomical skeletal nuclide distribution was studied after fission track or conventional autoradiography. Elimination of 239Pu and its translocation from bone surfaces to the bone volume caused by bone growth and turnover processes were measured. Average radiation doses and dose rates as a function of age at exposure were determined. Initial uptake and retention, skeletal nuclide concentration, proliferative activity of local cell populations and residence time of the nuclide on skeletal surfaces were affected significantly by age at exposure. The effect of these parameters on tumor induction is discussed. This study has provided early retention and distribution data which together with data from a chronic toxicity study will be used to estimate the risk of Pu exposure relative to that of Ra to humans of all ages.

This study was designed to determine whether alpha-receptor-stimulated monovalent ionic fluxes in rat aorta required calcium, and, if so, whether both extracellular calcium and cellularly stored calcium are active. Calcium removal in the presence of 10 mM magnesium (to maintain membrane stability) inhibited the norepinephrine-stimulated increase in potassium-42 and chloride-36 efflux. However, the norepinephrine-stimulated increase in sodium-24 influx was relatively resistant to calcium depletion. Protocols were designed to measure the time course for the changes in potassium-42 efflux and contraction when calcium was removed or replaced in the presence of norepinephrine. The dose-dependent effect of a calcium antagonist (diltiazem) was also measured. A close correlation (r = 0.94) was found between inhibition of contraction and potassium-42 effluxes which followed the regression: % potassium-42 response = 1.0 X (% contraction) + 1.8%). The slope of 1.0 and intercept near zero suggests the hypothesis that norepinephrine-stimulated potassium-42 efflux and contraction are codependent on cellular calcium concentration. This co-dependence held for short phasic responses (approximately 1 minute), as well as longer tonic responses (greater than or equal to 5 minutes). It appears that calcium-dependent potassium-42 effluxes can be supported by both the influx of extracellular calcium and release of cellular stores. It is concluded that calcium-dependent potassium channels (and possibly chloride channels) are operative in rat aorta and are an important component of the graded membrane response to norepinephrine. The sodium channels, however, do not appear to share this same calcium dependency.

This article describes the process from conception to implementation of developing a nurse-managed wellness center for senior citizens. The center was established in a federally subsidized high rise residential complex in midtown Manhattan. The unique senior population living in this New York City community includes a large proportion of performing artists. These individuals are struggling to maintain ties to their community at a time when their most productive performing years have passed. A health needs assessment was designed to evaluate whether or not these seniors were interested and would participate in a nurse-managed wellness center. The strategies needed to propose and move the project forward through all systems are explored. Two clinical nurse specialists assessed the need, proposed the center, and guided it through several political systems while maintaining leadership to establish a viable and innovative hospital-based health center based on prevention.