The "Puck" energetic charged particle detector: Design, heritage, and advancements

Energetic charged particle detectors characterize a portion of the plasma distribution function that plays critical roles in some physical processes, from carrying the currents in planetary ring currents to weathering the surfaces of planetary objects. For several low-resource missions in the past, the need was recognized for a low-resource but highly capable, mass-species-discriminating energetic particle sensor that could also obtain angular distributions without motors or mechanical articulation. This need led to the development of a compact Energetic Particle Detector (EPD), known as the "Puck" EPD (short for hockey puck), that is capable of determining the flux, angular distribution, and composition of incident ions between an energy range of ~10 keV to several MeV. This sensor makes simultaneous angular measurements of electron fluxes from the tens of keV to about 1 MeV. The same measurements can be extended down to approximately 1 keV/nucleon, with some composition ambiguity. These sensors have a proven flight heritage record that includes missions such as MErcury Surface, Space ENvironment, GEochemistry, and Ranging and New Horizons, with multiple sensors on each of Juno, Van Allen Probes, and Magnetospheric Multiscale. In this review paper we discuss the Puck EPD design, its heritage, unexpected results from these past missions and future advancements. We also discuss high-voltage anomalies that are thought to be associated with the use of curved foils, which is a new foil manufacturing processes utilized on recent Puck EPD designs. Finally, we discuss the important role Puck EPDs can potentially play in upcoming missions.

Induced Effects on Red Imported Fire Ant (Hymenoptera: Formicidae) Forager Size Ratios by Pseudacteon spp. (Diptera: Phoridae): Implications on Bait Size Selection

Red imported fire ants, Solenopsis invicta Buren, are adversely affected by phorid flies in the genus Pseudacteon by instigating defensive behaviors in their hosts, and in turn reducing the efficiency of S. invicta foraging. Multiple Pseudacteon species have been released in Texas, and research has been focused on the establishment and spread of these introduced biological control agents. Field experiments were conducted to determine bait particle size selection of S. invicta when exposed to phorid populations. Four different particle sizes of two candidate baits were offered to foragers (one provided by a pesticide manufacturer, and a laboratory-created bait). Foragers selectively were attracted to, and removed more 1-1.4-mm particles than any other bait size. The industry-provided bait is primarily made of particles in the 1.4-2.0 mm size, larger than what was selected by the ants in this study. While there was a preference for foragers to be attracted to and rest on the industry-provided blank bait, S. invicta removed more of the laboratory-created bait from the test vials. There was an abundance of workers with head widths ranging from 0.5-0.75 mm collected from baits. This was dissimilar from a previous study wherein phorid flies were not active and in which large workers were collected in higher abundance at the site. This implies that phorid fly activity caused a shift for red imported fire ant colonies to have fewer large foragers.

Effectiveness comparison of multiple sticky-trap configurations for sampling Pseudacteon spp. phorid flies (Diptera: Phoridae)

A variety of traps have been developed for monitoring introduced populations of Pseudacteon spp. phorid flies (Diptera: Phoridae) across their established range in the United States. Such traps typically exploit common aspects of phorid fly biology and behavior, such as their attraction to live or dead red imported fire ants, Solenopsis invicta Buren (Hymenoptera: Formicidae), as well as the perching behavior of these parasitoids. However, populations of multiple species of phorid flies have been established in the United States to serve as biological control agents against S. invicta, and it is unclear if all trap designs are equally effective in sampling this variety of phorid species. This study investigated the effectiveness of six trap designs simultaneously during three sampling events in south-central Texas. Interactions between two species of phorid flies (Pseudacteon tricuspis Borgmeier and P. curvatus B.) and their hosts have been intensively studied at this location for over eight years. When analyzed independently, there were no significant differences in the mean number of P. curvatus or P. tricuspis phorids collected by any of the trap designs during any of the sampling events. However, when the total number of phorids collected were combined, significant trap performance differentials were observed during the October 2010 sampling event. Furthermore, there were significant differences among male flies during the September 2012 observation. Additionally, a trap component cost comparison is provided. The consistent and relatively equivalent performance of the phorid traps investigated in these trials suggests that all are appropriate for phorid surveillance, and cost and ease-of-use considerations may be the most important criteria when selecting a trap design.

The elemental composition of asteroid 433 eros: results of the NEAR-shoemaker X-ray spectrometer

We report major element composition ratios for regions of the asteroid 433 Eros imaged during two solar flares and quiet sun conditions during the period of May to July 2000. Low aluminum abundances for all regions argue against global differentiation of Eros. Magnesium/silicon, aluminum/silicon, calcium/silicon, and iron/silicon ratios are best interpreted as a relatively primitive, chondritic composition. Marked depletions in sulfur and possible aluminum and calcium depletions, relative to ordinary chondrites, may represent signatures of limited partial melting or impact volatilization.

A preliminary study of immunologic and hematologic profiles of peripheral blood from Nebraska farmers who apply pesticides to their fields

OBJECTIVE

Laboratory studies have documented a wide range of pesticide-induced changes in the hematopoietic and lymphoreticular systems. Some of these are expressed as altered serum values, blood cell counts, and leucocyte functions. The goal of the present study was to determine whether these alterations were evident in peripheral blood of Nebraska farmers who applied pesticides to their fields.

METHODS

An invitation to participate was mailed to 100 residents (70 farmers; 30 controls) of Butler County, Nebraska. All respondents (51 farmers and 21 controls) were enrolled and surveyed by written questionnaire for health status and pesticide use. Our analysis included 45 farmers and 18 controls. The farmers were divided into a high (n = 23) and a low (n = 22) pesticide use group. Statistical correlations of ten blood values with both pesticide use and age were evaluated, since pesticide use correlated with age.

RESULTS

Four of the ten blood values correlated with pesticide use and age (Spearman Rho). In a multiple regression model, pesticide use (not age) proved to be a predictor of red blood cell count and hematocrit. In the same model, pesticide use was not a predictor of mean red cell volume or candida antigen-induced T-lymphocyte proliferation. Serum complement activity did not correlate with pesticide use among the farmers (n = 45) but was significantly reduced (ANOVA) in the high pesticide use group, compared to controls.

CONCLUSIONS

A preliminary study of blood values in a small cohort of Nebraska farmers found no pesticide-associated effects on 1) leucocyte count, 2) antigen- and mitogen-stimulated T-cell proliferation, 3) mitogen-stimulated B-cell proliferation, and 4) concentrations of serum IgG and IgM. The study found small but statistically significant pesticide-associated effects on red blood cells and serum complement.

Predicting clinical outcome of nonsurgical management of blunt splenic injury: using CT to reveal abnormalities of splenic vasculature

OBJECTIVE

Using CT to grade blunt splenic injuries frequently does not predict clinical outcome. This retrospective, blinded study evaluated whether revealing a traumatic pseudoaneurysm or frank hemorrhage on an initial CT examination can be used to predict the successful clinical outcome of patients managed without surgery.

MATERIALS AND METHODS

The medical and CT records of all patients with blunt splenic injury during a 5-year period were independently reviewed for vascular abnormalities. Also, the grade of injury was reconfirmed. Hemodynamically stable patients with injuries of grades 1-3 were managed without surgery. Clinical failure occurred if a patient required splenectomy or splenorrhaphy after any attempt of nonsurgical management.

RESULTS

Two hundred sixty-three patients were treated for blunt splenic injuries. Eighty-two of these patients underwent emergent surgery on the basis of clinical and peritoneal lavage findings without CT examination. The remaining 181 (69%) patients were initially evaluated with emergent abdominal CT. Of these 181 patients, 72 (40% of those undergoing CT) were treated nonsurgically. Nonsurgical therapy failed in 11 (15%) of these 72 patients. Of these 11 patients, nine (82%) had a defined vascular abnormality of the spleen. Only eight (13%) of the remaining 61 patients who underwent CT and successful nonsurgical management had a vascular abnormality of the spleen.

CONCLUSION

The failure rate in patients with nonsurgically managed blunt splenic injuries may be markedly reduced if patients with traumatic pseudoaneurysm or active hemorrhage revealed on emergent CT are treated with early surgical or endovascular repair.

Host Specificity of Gregarina blattarum von Siebold, 1839 (Apicomplexa: Eugregarinida) among Five Species of Domiciliary Cockroaches

The host specificity of Gregarina blattarum was evaluated among five species of domiciliary cockroaches: Blatella germanica, Supella longipalpa, Blatta orientalis, Periplaneta americana, and Periplaneta fuliginosa. Third- and fourth-instar nymphs were allowed to feed on crushed dog kibble contaminated with G. blattarum oocysts. Cockroaches were killed 8 days postinfection and examined for parasites. Gregarina blattarum infections were observed in all experimentally infected replications of B. germanica. No infection was observed in an experimentally infected replication of S. longipalpa, B. orientalis, P. americana, or P. fuliginosa, nor was an infection observed in a time zero or ending time control group. In vitro excystation assays using extracts of host gut homogenates demonstrate that G. blattarum sporozoites successfully excyst and begin the life cycle in all five cockroach species tested. No excystation was observed in neutral buffered saline controls. These data suggest that G. blattarum comprises a complex of cryptic species marked by narrow host utilization rather than a single species parasitizing a broad array of cockroach taxa.

CT aortography of thoracic aortic rupture

OBJECTIVE

Emergent aortography is commonly used to confirm and define a suspected thoracic aortic rupture detected by CT screening. We evaluated whether helical CT aortography can replace transcatheter aortography for critically injured patients.

SUBJECTS AND METHODS

Over 22 months, 38 thoracic aorta and great vessel injuries were detected in 3229 patients with nontrivial blunt chest trauma who underwent helical CT screening. Planar, oblique, and curved two-dimensional reconstructions and three-dimensional shaded-surface display and maximum intensity projection volume-rendering techniques were used to evaluate the aortic injuries. Transcatheter aortography or surgery was performed in all stable patients.

RESULTS

Twenty-eight of the injuries involved the descending thoracic aorta. All such injuries were best identified on axial images before CT angiography. CT angiography adequately showed tears over 15 mm long. Smaller tears required axial images for corroboration.

CONCLUSION

Technically adequate axial helical CT detects and defines all injuries of the thoracic aorta. CT angiography supplements the conventional examination and can replace transcatheter aortography except for small tears or indeterminate studies.

Blunt traumatic aortic rupture: detection with helical CT of the chest

PURPOSE

To determine the effectiveness of helical computed tomography (CT) as a screening device to detect traumatic aortic rupture.

MATERIALS AND METHODS

Helical CT was used to examine 1,518 patients with nontrivial blunt trauma. Of these patients, 127 (8.37%) with abnormal CT scans of the mediastinum or aorta underwent thoracic aortography--89 patients solely for evaluation of mediastinal hematoma depicted at CT. Imaging abnormalities were correlated with surgical or clinical outcome.

RESULTS

Twenty-one aortic injuries were identified that ranged from subtle intimal flaps to complete aortic disruption. Helical CT was more sensitive than aortography (100% versus 94.4%, respectively) but less specific (81.7% versus 96.3%, respectively) in detection of aortic injuries in patients who underwent both examinations. The association between CT findings and outcome was phi = 0.62 (chi2 = 49.1, 1 df, P < .01) and between aortography and outcome was phi = 0.85 (chi2 = 92.2, 1 df, P < .001). The P value of the difference between the phi coefficients was .10.

CONCLUSION

Helical CT of the chest is effective for screening critically injured patients with possible blunt thoracic aortic injuries.

Over the southern solar pole: low-energy interplanetary charged particles

The heliosphere instrument for spectrum, composition, and anisotropy (HISCALE) recorded the fluxes of low-energy ions and electrons (> 50 kiloelectron volts) when Ulysses crossed the southern solar polar region and revealed that the large-scale structure of the heliosphere to at least approximately -75 degrees was significantly influenced by the near-equatorial heliospheric current sheet. Electrons in particular were accelerated by the current sheet-produced and poleward-propagating interplanetary reverse shock at helioradii far from the Ulysses location. At heliolatitudes higher than approximately -75 degrees on the Ulysses ascent to the pole and approximately -50 degrees on the descent, small, less regular enhancements of the lowest energy electron fluxes were measured whose relations to the current sheet were less clear. The anomalous component of low-energy (approximately 2 to 5 megaelectron volts per nucleon) oxygen flux at the highest heliolatitudes was found to be approximately 10(-8) [per square centimeter per second per steradian (per kiloelectronvolt per nucleon)]; the anomalous Ne/O ratio was approximately 0.25.

Distention arthrography in the treatment of adhesive capsulitis of the shoulder

PURPOSE

Adhesive capsulitis involving the glenohumeral joint (frozen shoulder) is an insidious and painful condition that results in gradual loss of joint motion. Recovery is frequently prolonged despite multiple therapeutic maneuvers. The authors investigate the mechanism of action and the long-term clinical result of distention arthrography for the treatment of patients with frozen shoulder.

PATIENTS AND METHODS

Sixteen patients with adhesive capsulitis of the shoulder were treated with therapeutic capsular distention by using intra-articular injection of a 30-mL mixture of lidocaine, corticosteroid, and contrast media immediately following diagnostic arthrography.

RESULTS

Capsular disruption was demonstrated in all cases. Thirteen patients (80%) experienced immediate pain relief and increased shoulder mobility. This improvement was maintained over a follow-up interval of 6 months or more. Disruption occurred at the subscapular bursa in eight patients, the subacromial bursa in six, and the distal bicipital tendon sheath in two. These latter two patients had no pain relief.

CONCLUSION

Arthrographic distention of the constricted capsule appears to be an excellent therapeutic intervention for achieving rapid symptomatic relief from adhesive capsulitis.

Distribution and seasonal and diurnal activity patterns of Eutrombicula alfreddugesi (Acari: Trombiculidae) in a forest edge ecosystem

Microclimatic and vegetative effects on the population size and activity patterns of larval Eutrombicula alfreddugesi Oudemans, 1910 (Acari: Trombiculidae), were investigated in Nebraska between latitude 40 degrees 0'0" N and 40 degrees 1'21" N. Larval population densities along a forest edge were greatest in areas of high relative humidity, moderate temperature, low incident sunlight, and increasing substrate vegetation. Although chigger populations existed throughout the forest edge, larger populations concentrated in short- to tall-grass transition zones. Chiggers were rarely found in the undergrowth beneath the tree canopy. Chigger activity correlated with a microclimatically driven diurnal rhythm. Activity was greatest during the late afternoon-early evening, between 1530 and 1930 hours (CDST). Larval activity dropped to low levels and remained so until sunrise; this period of reduced activity occurred between 1930 and 0530 hours. Small increases in larval activity occurred around sunrise (approximately 0600-0700 hours). Between about 0700 and 1530 hours, larval E. alfreddugesi were inactive and did not respond to normal sampling stimuli. Larval populations appeared in late April through early May, peaked in abundance in late June and early July, diminished through late summer, and disappeared in midautumn as the ground began to freeze.

Inhibition of interleukin-2-stimulated enhancement of human natural killer (NK) cell activity by carbaryl, an anticholinesterase insecticide

The potency of the anticholinesterase (antiCHE) insecticides as serine hydrolase inhibitors, and evidence for serine hydrolase activity in interleukin-2 (IL2) signalling suggest that the natural killer (NK) cell may be a target for dysregulation by antiCHE insecticides. NK cells are large granular lymphocytes (LGL) that respond to IL2 by proliferating and increasing their cytolytic efficiency. In the present study, we assessed the effects of carbaryl (CA, an antiCHE insecticide) and alpha-naphthol (NA, the major metabolite of CA) on both target cell killing per se and IL2 enhancement of target cell killing by human NK cells. Human LGL, collected from the peripheral blood of normal donors, were cultured for 4 days with human recombinant IL2 (HRIL2), then assayed by a 51Chromium (51Cr) release assay for lytic activity against human K562 cells. When added at the beginning of the culture period, CA inhibited enhancement of cytolytic efficiency in a concentration-dependent manner; at concentrations (0.5 and 5.0 microM) compatible with no cholinergic toxicity. Reduction of the effector/target cell (E/T) ratio in the 51Cr release assay markedly enhanced the observed inhibition by CA. In one experiment, inhibition increased from 6% to 20%, 17% to 35%, and 53% to 73% at 0.5, 5.0, and 50 microM CA, respectively, when E/T was reduced from 10:1 to 2.5:1. This result is consistent with reduced cytolytic efficiency of individual NK cells exposed to CA. NA had no effect at 0.5 or 5.0 microM but caused some inhibition at 50 microM. Neither CA nor NA produced LGL death. When CA or NA was added directly to the 51Cr release assay, inhibition was not observed. The mechanism of inhibition of IL2-stimulated enhancement of target cell killing is not yet known, however, the results are consistent with impairment of IL2 signalling, by CA.

Preoperative embolization of the spleen in children with hypersplenism

Splenomegaly associated with myelodysplastic disorders in children may be massive and can result in pancytopenia, abdominal discomfort, and respiratory distress. When these symptoms cannot be relieved by nonsurgical means, splenectomy may be indicated. Under such conditions, surgical splenectomy carries increased risks, as the thrombocytopenia is difficult to correct secondary to splenic sequestration. Additionally, the surgical anatomy is often distorted secondary to the massive spleen and dissection can be difficult. These factors can lead to uncontrollable hemorrhage. In an attempt to decrease intraoperative blood loss, the authors successfully performed preoperative splenic artery embolization in 11 of 12 children (age range, 1-11 years) with pancytopenia due to hypersplenism. Hypersplenism requiring surgical splenectomy was due to leukemia (n = 9), myelodysplastic syndrome (n = 1), immune thrombocytopenia (n = 1), and osteopetrosis (n = 1). Embolization was performed under general anesthesia, prior to surgery, with gelatin sponge particles alone, Gianturco coils alone, or a combination of polyvinyl alcohol sponge particles and Gianturco coils. Embolization allowed for safe surgical splenectomy.

The Hot Plasma Environment at Jupiter: Ulysses Results

Measurements of the hot plasma environment during the Ulysses flyby of Jupiter have revealed several new discoveries related to this large rotating astrophysical system. The Jovian magnetosphere was found by Ulysses to be very extended, with the day-side magnetopause located at approximately 105 Jupiter radii. The heavy ion (sulfur, oxygen, and sodium) population in the day-side magnetosphere increased sharply at approximately 86 Jupiter radii. This is somewhat more extended than the "inner" magnetosphere boundary region identified by the Voyager hot plasma measurements. In the day-side magnetosphere, the ion fluxes have the anisotropy direction expected for corotation with the planet, with the magnitude of the anisotropy increasing when the spacecraft becomes more immersed in the hot plasma sheet. The relative abundances of sulfur, oxygen, and sodium to helium decreased somewhat with decreasing radial distance from the planet on the day-side, which suggests that the abundances of the Jupiter-derived species are dependent on latitude. In the dusk-side, high-latitude region, intense fluxes of counter-streaming ions and electrons were discovered from the edge of the plasma sheet to the dusk-side magnetopause. These beams of electrons and ions were found to be very tightly aligned with the magnetic field and to be superimposed on a time- and space-variable isotropic hot plasma background. The currents carried by the measured hot plasma particles are typically approximately 1.6 x 10(-4) microamperes per square meter or approximately 8 x 10(5) amperes per squared Jupiter radius throughout the high-latitude magnetosphere volume. It is likely that the intense particle beams discovered at high Jovian latitudes produce auroras in the polar caps of the planet.

Modulation of interleukin-2-driven proliferation of human large granular lymphocytes by carbaryl, an anticholinesterase insecticide

Studies in other laboratories have provided evidence that the interleukin-2 (IL2) signaling pathway in lymphocytes includes essential, serine proteases. Since the anticholinesterase (antiCHE) insecticides are potent serine hydrolase (esterase and protease) inhibitors, we assessed the ability of carbaryl (CA, a widely used antiCHE insecticide) and alpha-naphthol (NA, a major metabolite of carbaryl) to modulate IL2-driven proliferation of large granular lymphocytes (LGL) purified from human peripheral blood. These cells express nearly all of the natural killer (NK) activity of human peripheral blood. NK cells are normal lymphocytes that respond to IL2 by proliferating and increasing their tumoricidal activity on a per cell basis. Cultures of purified LGL, initiated in the presence of human recombinant IL2, were harvested on culture Day 4, then proliferation was measured as [3H]thymidine incorporation. When added only at the time cultures were initiated. CA inhibited incorporation 10-32%, 35-53%, and 54-57% at 0.5, 5.0, and 50 microM, respectively. In contrast, NA had no effect at 0.5 and 5.0 microM, but was inhibitory (16-17%) at 50 microM. Reexposure to CA or NA, during the incorporation assay, had little effect on the observed inhibition profiles. Chemically induced changes in cell number during an 8-day culture period reflect the chemically induced changes in [3H]thymidine incorporation. Neither CA nor NA produced cell death. Quantitation of both CA and NA by HPLC indicated a rapid loss of CA (ca. 95% in 24 hr) and a much slower loss of NA from the culture medium. CA inhibited human LGL proliferation at concentrations producing little or no inhibition of serum CHE, an indicator of exposure to antiCHE insecticides.

Bronchial arteriography and embolotherapy for hemoptysis in patients with cystic fibrosis

Bronchial arteriography and embolotherapy were performed to control hemoptysis in 11 patients with advanced stages of cystic fibrosis. Two patients suffered massive, 1 moderate, and 8 mild but recurrent hemoptysis. The embolization procedures were performed with Gelfoam, Ivalon, and coils in one to four separate procedures. Altogether, 19 of 20 procedures were successful, with follow-up periods ranging from 9 months to 8 years. No serious complications were encountered except for one femoral artery pseudoaneurysm which required surgical repair. Rapid digital subtraction angiography and "roadmapping" were considered helpful in avoiding the complication of reflux embolization and expediting the procedures. Bronchial embolization is a life-saving procedure for severe hemoptysis in patients with cystic fibrosis and is considered safe enough to include the indications of moderate and mild/recurrent hemoptysis to improve the quality of life in these patients.

Trauma center imaging problems: proposed solution with picture archiving communication systems

Radiologic support for trauma center activities presents special problems that are discussed. This article proposed the use of a picture archiving communication system (PACS) as a potential solution. A sample PACS for this purpose is described to illustrate this approach.

Polysplenia syndrome in the asymptomatic adult: computed tomography evaluation

Although the majority of patients with polysplenia syndrome will present during infancy or childhood with congenital heart disease, 5% to 10% will have no cardiac disease; and the associated abnormalities may not be discovered until adulthood. Physicians should be familiar with the chest and abdominal radiographic findings so as not to confuse this syndrome with other, more common pathologic conditions in asymptomatic adult patients.

Initial experience with a universal-length copolymer ureteral stent

A universal-length ureteral stent made of a biocompatible copolymer was designed specifically for easy antegrade internal placement. The double-looped distal end of the stent eliminates the need to measure the distance from the ureteropelvic to ureterovesical junction. If additional length is required, a portion of the distal loop is incorporated into the stent shaft. Interventional radiology practices benefit economically, as the universal-length stent is the only size required for the treatment of most ureteral obstructions.

Silent deep vein thrombosis in immobilized multiple trauma patients

Although few trauma patients sustain fatal pulmonary embolism, a large population is at risk from nonfatal embolism due to unrecognized deep vein thrombosis (DVT). Thirty-eight of 39 immobilized trauma patients at bed rest for 10 days or longer had venographic study of their lower extremities to evaluate for the presence of silent DVT. Sixty percent of patients had silent DVT, with thrombi extending above the knee in half the patients with clot. DVT was documented in 67 percent of patients with major lower extremity fractures and 59 percent of patients without major fractures. DVT increased with increasing age but not with injury severity score.

Computed tomography in acute fatty liver of pregnancy

A case of the diagnosis of acute fatty liver of pregnancy proved by biopsy is described. In this case computed tomography showed decreased attenuation over the liver, and this attenuation is compatible with fatty infiltration. Computed tomography may be useful in the differential diagnosis of jaundice in pregnancy.

Vascular trauma to the extremities and lower neck: initial assessment with intravenous digital subtraction angiography

Rapid assessment of a patient with possible major peripheral vascular injury is essential to preserve limb function. Intravenous digital subtraction angiography (IV DSA) allows rapid evaluation of these patients without the need for intraarterial examination. We report our experience in 295 vessels studied by IV DSA for the evaluation of possible traumatic arterial injury to the extremities or neck. Of our study population requiring angiography (469 patients), 63.4% were appropriate candidates for IV DSA. Of the vessels studied by IV DSA, 93.6% required no further radiologic evaluation. A normal appearance on IV DSA study indicates no major vascular injury; patients with positive studies may proceed to surgery without further interventional assessment.

Pediatric digital subtraction angiography: intraarterial and intracardiac applications

Intraarterial digital subtraction angiography (IA-DSA) was performed in 80 pediatric patients. Forty-four underwent arterial injections with digital filming techniques. Of the 130 injections, DSA imaging was good or excellent in 121, often allowing resolution of vessels 1 mm in size. Thirty-six of the 80 patients underwent cardiac evaluation with intra-cardiac injections. Improved contrast resolution with IA-DSA allowed the use of smaller catheters (3-4F) and smaller amounts of contrast material. Immediate availability of subtracted images (no film processing delay) resulted in shorter total procedure time. Outpatient studies are possible. IA-DSA provides several notable advantages for the pediatric patient.

Cytology of basidiospore germination, penetration, and early colonization of Phaseolus vulgaris by Uromyces appendiculatus var. appendiculatus

Cytological studies were done on a compatible interaction between Phaseolus vulgaris and Uromyces appendiculatus var. appendiculatus. The cytoplasm of germinated basidiospores contained numerous microbodies in close association with lipid bodies, vacuoles, and endoplasmic reticulum. A single, polar germ tube commonly developed from a germinating basidiospore. The germ tubes tended to grow toward or along the junction lines between host epidermal cells. Appressorium formation in ca. 75% of all observations occurred less than 3.5 μm away from the lines of juncture. A mucilaginous exudate was associated with germ tubes and appressoria along areas of contact between host and fungus. Epidermal wall papillae were often observed beneath basidiospores and appressoria but did not restrict entrance of the fungus. The fungus directly penetrated the epidermal cell and invaginated the host plasma membrane. The apex of the penetration peg expanded to form an ovate intraepidermal vesicle. Electron-opaque material occluded the penetration pore after migration of the usually binucleate protoplast into the vesicle. The intraepidermal vesicle developed apically and formed a multicellular primary hypha that initially was multinucleate and later became uninucleate or binucleate. The primary hypha then grew into adjacent epidermal cells, subtending palisade parenchyma cells and underlying intercellular spaces.

Evaluation of vascular rings with digital subtraction angiography

Seven patients with vascular rings were evaluated over a 2-year period with intravenous digital subtraction angiography (DSA), which was compared with screen-film aortography or cineangiography. The seven patients were also evaluated with barium esophagography. Six of the seven DSA images were totally diagnostic and one study was only partly diagnostic. Six of the seven vascular anomalies were confirmed surgically. DSA is suggested as an alternative to arteriography in evaluating patients with suspected vascular rings.

Digital venous angiography. A prospective evaluation in peripheral arterial trauma

Digital venous angiography (DVA), a new radiographic technique, was prospectively compared to conventional intra-arterial angiography (CA) in a group of 153 patients with trauma and suspected peripheral arterial injury ( PAI ). Criteria for entry included: large hematoma, proximity to a major vessel, shotgun wounds, blunt injury of the extremities, and fractures or dislocations of areas with high risk of arterial injury. Patients with unequivocal clinical evidence of PAI were excluded. Study patients had both DVA and CA. Sixteen injuries were diagnosed: lacerations (9), transection (1), AV fistulae (2), thromboses (2) and minute intimal flaps (2). All patients with abnormal studies were surgically explored; there were no false-positives. There were no known false-negatives with CA. The intimal flaps were not recognized initially on DVA and their clinical significance is questioned. DVA, compared to CA in PAI , had decreased patient discomfort, cost, and morbidity. It has the potential for study of multiple areas of the body from a single I.V. catheter. DVA can probably replace CA for civilian penetrating wounds. CA may remain the standard for blunt and high velocity injuries.

Biliary tract neoplasms: a simple management technique

This paper presents a simple, fast, and accurate afterloading method of delivering high radiation dose to tumors of the biliary tract, using radioactive iridium through a biliary drainage catheter. A Tuohy Borst sidearm adaptor permits concurrent drainage. The dose delivered in this manner can be used to supplement the palliative external beam radiotherapy, with minimal side effect.

Simplified brush biopsy of the bile ducts

A simple and convenient technique is presented for the performance of transluminal brush biopsies of biliary tract lesions. Since a guide wire is maintained in position through the obstruction, the technique can be performed at any time without loss of access to that lesion.

Pulmonary artery occlusion due to histoplasmosis

Histoplasma mediastinitis with complete or partial pulmonary artery obstruction due to compression and/or intraluminal granuloma was diagnosed in five patients and surgically verified in two. The patients, ages 12-27 years, had cough, dyspnea (four cases), and hemoptysis (two cases). Radionuclide imaging showed unilateral absence of pulmonary perfusion and minimal diminution of ventilation. Differentiation of this inflammatory process from other causes of ventilation-perfusion mismatch, for example, congenital hypoplasia and certain acquired causes of arterial obstruction, especially thromboembolism, may be possible by correlating radiographs, laminograms, and clinical history. Angiography can delineate the extent of perfusion impairment and may suggest its cause.

Exposure of urban applicators to carbaryl

Thirty-eight urban volunteers from the Lincoln and Omaha, Nebraska areas were monitored for carbaryl exposure during the summer of 1979. All volunteers were involved in the application of carbaryl incidental to their employment or leisure activities. The investigators made no attempt to affect the method of carbaryl application. The mean rates of carbaryl exposure were 3.85 and 0.26 microgram cm-2 hr-1, respectively, for the outside of the clothing and the skin beneath the clothing; clothing apparently provided an effective barrier to carbaryl penetration. The rate of carbaryl exposure to the hands of applicators was 2.36 and 24.96 micrograms cm-21 hr-1, respectively, for applicators with and without gloves. The maximum dermal exposure recorded in this study was 2.86 mg kg-1 hr-1 which is significantly less than the stimated dermal LD50 value for carbaryl (4000 mg kg-1). The maximum air concentration of carbaryl was 0.28 microgram L-1. Only a small mean decrease was found in the applicators serum (-1.01%) or erythrocyte (-1.39%) acetylcholinesterase activity. Although some applicators had decreases in either serum or erythrocyte acetylcholinesterase activity greater than 20%, an equal number had increases of the same magnitude. The mean total carbaryl exposure to the applicators, expressed as a percent of toxic dose per hr, was 0.01%, with a maximum estimated exposure of 0.08%.

Exposure of professional pesticide applicators to carbaryl

Dermal and respiratory exposure, and erythrocyte and serum acetylcholinesterase activity were monitored on two groups of professional pesticide applicators spraying trees with carbaryl. The mean dermal exposure to the first group was 128 mg hr-1 of carbaryl and the mean respiratory exposure was 0.1 mg hr-1. The maximum percent (%) toxic dose received by the applicators was 0.12% hr-1. The mean exposure to the second group of applicators was 59.4 mg hr-1 dermal and 0.1 mg hr-1 respiratory, for a total of 0.02% toxic dose per hr. It was estimated that 86.9% of the dermal exposure was to the forearms and hands. The rate of exposure to pads placed under the applicators clothing was approximately 1/20 that of pads on the outside of the clothing. Of the body areas monitored, the back received the least rate of exposure. It was determined, in vitro, that 10(-3) M carbaryl would inhibit human serum (pseudocholinesterase) and erythrocyte acetylcholinesterase for at least 72 hr. There was no overall inhibition of acetylcholinesterase activity in the applicators.