Borrelia burgdorferi not detected in widespread Ixodes scapularis (Acari: Ixodidae) collected from white-tailed deer in Tennessee.

Lyme disease (LD), caused by the bacterium Borrelia burgdorferi and transmitted in the eastern United States by blacklegged ticks, Ixodes scapularis Say, is classified as nonendemic in Tennessee and surrounding states in the Southeast. Low incidence of LD in these states has been attributed, in part, to vector ticks being scarce or absent; however, tick survey data for many counties are incomplete or out of date. To improve our knowledge of the distribution, abundance, and Borrelia spp. prevalence of I. scapularis, we collected ticks from 1,018 hunter-harvested white-tailed deer (Odocoileus virginianus (Zimmerman)) from 71 of 95 Tennessee counties in fall 2007 and 2008. In total, 160 deer (15.7%) from 35 counties were infested with adult I. scapularis; 30 of these counties were new distributional records for this tick. The mean number of I. scapularis collected per infested deer was 5.4 +/- 0.6 SE. Of the 883 I. scapularis we removed from deer, none were positive for B. burgdorferi and one tested positive for B. miyamotoi. Deer are not reservoir hosts for B. burgdorferi; nevertheless, past surveys in northern LD-endemic states have readily detected B. burgdoreferi in ticks collected from deer. We conclude that I. scapularis is far more widespread in Tennessee than previously reported. The absence of detectable B. burgdorferi infection among these ticks suggests that the LD risk posed by I. scapularis in the surveyed areas of Tennessee is much lower than in LD-endemic areas of the Northeast and upper Midwest.

Conductive paper fabricated by layer-by-layer assembly of polyelectrolytes and ITO nanoparticles.

A new salt-free approach was developed for fabricating conductive paper by layer-by-layer (LBL) assembly of conductive indium tin oxide (ITO) nanoparticles and polyelectrolytes onto wood fibers. Subsequent to the coating procedure, the fibers were manufactured into conductive paper using traditional paper making methods. The wood fibers were first coated with polyethyleneimine (PEI) and then LBL assembled with poly(sodium 4-styrenesulfonate) (PSS) and ITO for several bilayers. The surface charge intensity of both the ITO nanoparticles and the coated wood fibers were evaluated by measuring the zeta-potential of the nanoparticles and short fibers, respectively. The ITO nanoparticles were found to preferentially aggregate on defects on the fiber surfaces and formed interconnected paths, which led to the formation of conductive percolation paths throughout the whole paper. With ten bilayer coatings, the as-made paper was made DC conductive, and its sigma(dc) was measured to be 5.2 x 10(-6) S cm(-1) in the in-plane (IP) direction, while the conductivity was 1.9 x 10(-8) S cm(-1) in the through-the-thickness (TT) direction. The percolation phenomena in these LBL-assembled ITO-coated paper fibers was evaluated using scanning electron microscopy (SEM), current atomic force microscopy (I-AFM), and impedance measurements. The AC electrical properties are reported for frequencies ranging from 0.01 Hz to 1 MHz. A clear transition from insulating to conducting behavior is observed in the AC conductivity.

A large population of 'Lyman-break' galaxies in a protocluster at redshift z approximately 4.1.

The most massive galaxies and the richest clusters are believed to have emerged from regions with the largest enhancements of mass density relative to the surrounding space. Distant radio galaxies may pinpoint the locations of the ancestors of rich clusters, because they are massive systems associated with 'overdensities' of galaxies that are bright in the Lyman-alpha line of hydrogen. A powerful technique for detecting high-redshift galaxies is to search for the characteristic 'Lyman break' feature in the galaxy colour, at wavelengths just shortwards of Lyalpha, which is due to absorption of radiation from the galaxy by the intervening intergalactic medium. Here we report multicolour imaging of the most distant candidate protocluster, TN J1338-1942 at a redshift z approximately 4.1. We find a large number of objects with the characteristic colours of galaxies at that redshift, and we show that this excess is concentrated around the targeted dominant radio galaxy. Our data therefore indicate that TN J1338-1942 is indeed the most distant cluster progenitor of a rich local cluster, and that galaxy clusters began forming when the Universe was only ten per cent of its present age.

First isolation of La Crosse virus from naturally infected Aedes albopictus.

La Crosse (LAC) virus, a California serogroup bunyavirus, is the leading cause of pediatric arboviral encephalitis in the United States and an emerging disease in Tennessee, West Virginia, and North Carolina. Human cases of LAC encephalitis in Tennessee and North Carolina have increased above endemic levels during 1997 to 1999 and may represent an expansion of a new southeastern endemic focus. This report describes the isolation of LAC virus from the exotic mosquito Aedes albopictus. The discovery of LAC virus in wild populations of Ae. albopictus coupled with its expanding distribution in the southeastern United States, suggests that this mosquito may become an important accessory vector, potentially increasing the number of human cases in endemic foci or expanding the range of the disease.

Inhaled nitrous oxide versus placebo as an analgesic and anxiolytic adjunct to peripheral intravenous cannulation.

The objective was to determine whether an inhaled 50:50 mixture of nitrous oxide and oxygen (N(2)O/O(2)) provides significant pain and anxiety relief during intravenous cannulation in healthy adults. The study was conducted at the ED of a military teaching hospital. Participants included adult volunteers aged 18 to 50 years. Excluded were those with allergy to N(2)O, anemia, cardiac disease, pregnancy, asthma, or bone marrow disorder. A prospective, randomized, double-blind, placebo-controlled crossover design was used comparing a 50:50 mixture of N(2)O/O(2) versus O(2). After recording baseline nonhatched 100mm visual analog scales (VAS) for pain and anxiety, subjects inhaled gas 1 for 120 seconds, followed by antecubital intravenous cannulation, discontinuance of gas and VAS rating of procedural pain and anxiety. After 15 minutes, the experiment was repeated with gas 2. Ten subjects would detect a 12mm difference in pain or anxiety with a standard deviation of 10 mm, an alpha error under 0.05 and a power over 80%. Differences between VAS were compared by matched 2-tailed t-test. Eleven subjects were enrolled. One withdrew because of dizziness while inhaling gas (N(2)O). The 10 remaining subjects reported significantly less pain (N(2)O/O(2) 14.5mm, SD 18; O(2) 34.3mm, SD 23.4; P < .01) and anxiety (N(2)O/O(2) - 7.9mm, SD 7.8; O(2) 6.0mm, SD 11.6; P < .02) when inhaling N(2)O/O(2) than when inhaling O(2) alone. N(2)O/O(2) provided significant pain and anxiety reductions during intravenous cannulation. Some patients may experience adverse perceptions while using N(2)O, limiting its utility. Further studies defining the role of N(2)O as an anxiolytic agent, efficacy in actual patients, and cost comparisons with intravenous conscious analgesia/sedation, are warranted.

U.S. Army MEDEVAC in the new millennium: a medical perspective.

The U.S. Army Aeromedical Evacuation community (MEDEVAC) possesses a long-standing tradition of excellence in the care and transportation of combat casualties. Recent developments in civilian air medical transport and quantitative review of MEDEVAC operations have identified potential areas for improvement, concentrating on enhanced flight medic standards, training, sustainment and medical oversight of the air ambulance system. These proposed changes are discussed in detail, from the perspective of current emergency medicine and aviation medicine standards of practice. If instituted, these changes would facilitate the emergence of a true air medical transport capability comparable with the civilian community standard.

U.S. Army air ambulance operations in El Paso, Texas: a descriptive study and system review.

OBJECTIVES: To analyze a high-volume military air ambulance unit and review the U.S. Army air medical transport system and Military Assistance to Safety and Traffic (MAST) program. METHODS: The setting was a remote medical system with numerous ground emergency medical services. All patients transported between January 1, 1996, and February 28, 1998, were included. Patients who were dead on scene or for whom records were unavailable were excluded. A retrospective review of transport and available inpatient records was conducted. RESULTS: Five hundred seventeen patients were transported during the study period; 461 patients met inclusion criteria (89%). Of these, 70% were classified as trauma; 30% possessed medical or other surgical diagnoses. Prehospital responses numbered 71.6%, while 28.4% were interhospital transfers. Missions averaged 23.4 minutes per flight, with no major aircraft mishaps. Prehospital utilization review showed appropriate use; 35% of interhospital trauma and 11% of interhospital nontrauma missions were staffed inadequately by these criteria. Time intervals, procedures, and program impact are discussed. CONCLUSION: This and similar units participating in the MAST program provide effective air transport in settings underserved by civilian programs. Quality and wartime readiness could be improved by centralized medical direction, treatment and transfer protocols, and enhanced training of medics. Further investigations of the clinical impact of advanced training and a two-medic aircrew model are warranted.

Military assistance to safety and traffic services in El Paso: a retrospective analysis.

This study was performed to evaluate the performance of military rotary air medical transport in the El Paso, Texas, region with regard to mortality. A retrospective review of transport and inpatient medical records was undertaken. All trauma patients air transported from January 1, 1996, to February 28, 1998, were included. Patients for whom records were unavailable were excluded. Mean time intervals for prehospital and interhospital transport were calculated. Injury severity and survival data were calculated using Revised Trauma Score, Injury Severity Score, and Trauma and Injury Severity Score (TRISS) methodology. Two hundred sixty-seven patients were eligible for analysis (83% of the total). TRISS analysis predicted 241 survivors; the actual number of survivors was 241 (mean = 0.98, z = 0.03) despite the fact that 6 individuals died who were predicted to live and 3 individuals lived who were predicted to die. We conclude that the actual mortality rate of those patients transported by military aeromedical lift equaled that predicted by TRISS methodology.

Adenosine conversion of supraventricular tachycardia associated with high-dose epinephrine therapy for cardiac arrest.

Adenosine has received wide acceptance as the drug of choice for initial treatment of supraventricular tachycardias (SVT), and as a diagnostic adjunct in hemodynamically stable, wide-complex tachycardias. This report describes the successful use of adenosine for the treatment of SVT occurring after successful initial resuscitation from ventricular fibrillation, in which a high dose of the epinephrine protocol was used.

Newly recognized focus of La Crosse encephalitis in Tennessee.

La Crosse virus is a mosquito-borne arbovirus that causes encephalitis in children. Only nine cases were reported in Tennessee during the 33-year period from 1964-1996. We investigated a cluster of La Crosse encephalitis cases in eastern Tennessee in 1997. Medical records of all suspected cases of La Crosse virus infection at a pediatric referral hospital were reviewed, and surveillance was enhanced in the region. Previous unreported cases were identified by surveying 20 hospitals in the surrounding 16 counties. Mosquito eggs were collected from five sites. Ten cases of La Crosse encephalitis were serologically confirmed. None of the patients had been discharged from hospitals in the region with diagnosed La Crosse encephalitis in the preceding 5 years. Aedes triseriatus and Aedes albopictus were collected at the case sites; none of the mosquitos had detectable La Crosse virus. This cluster may represent an extension of a recently identified endemic focus of La Crosse virus infection in West Virginia.

Field deployment of automated external defibrillators to a Federal Fire Service unit under medical direction of a military emergency service.

Automated external defibrillators (AEDs) have been proven in numerous studies to decrease the time interval from cardiac arrest to defibrillation, thus improving the survival rate for victims of ventricular fibrillation and pulseless ventricular tachycardia, the most common causes of reversible sudden cardiac death. Recent Department of Defense initiatives have mandated increased participation of Federal Fire Service units in the conduct of prehospital emergency medical care on military and other federal installations. This report describes the development and deployment of an AED program for a fire department serving a U.S. military installation under the medical direction of that installation's medical treatment facility. This "first step" in the integration of Federal Fire Services into emergency medical care, as well as potential future military applications for AEDs, are discussed.

Sucking lice (Anoplura) of mammals of Tennessee.

Twenty-five species of sucking lice are recorded from wild and domestic mammals, including humans, from Tennessee. Collections of 10 of these species (Haematopinus eurysternus, Hoplopleura captiosa, Hoplopleura hirsuta, Hoplopleura oryzomydis, Hoplopleura trispinosa, Linognathus africanus, Linognathus setosus, Linognathus vituli, Neohaematopinus sciuropteri and Polyplax auricularis) represent newly documented state records. Host specificity was exhibited by 22 species of lice with each of these species being recovered from just one mammal species. Louse infestation prevalences are included for large samples of hosts. A host-parasite list for Tennessean sucking lice is included.

Surgical treatment of persistent exit-site infections.

Persistent exit-site infections and tunnel infections (ESI/TI) are a cause for removal of Swan neck catheters (SNC). Previous studies report variable success in the treatment of these infections by surgical exposure and removal of the subcutaneous external cuff. We report our experience with this technique. All 5 patients with persistent ESI/TI were successfully treated with antibiotics and surgical intervention. All cultures grew Staphylococcus aureus. Average time to complete healing after surgical exposure was 39.4 days. Mean follow-up after complete healing was 164.8 days. There were no subsequent episodes of ESI/TI in these patients. None of the catheters subsequently malfunctioned or developed leaks. Persistent ESI/TI in Swan neck catheters can be successfully treated with surgical exposure and removal of the subcutaneous external cuff.

Ehrlichiosis in a golf-oriented retirement community.

BACKGROUND: Ehrlichiosis due to Ehrlichia chaffeensis usually occurs sporadically or in small clusters, with an annual incidence estimated at 3 to 5 cases per 100,000 population in areas of endemic disease. The putative principal vector is the Lone Star tick (Amblyomma americanum). We investigated an outbreak of ehrlichiosis that occurred in June 1993 among members of a golf-oriented retirement community (community A) in Tennessee. The community is densely wooded and borders a wildlife-management area where deer are numerous. METHODS: We conducted a case-control study, using medical-history reviews, serologic testing, and testing with the polymerase chain reaction for E. chaffeensis infection. We also surveyed a sample of 10 percent of the households in community A and in another golf-oriented community (community B) more than 20 miles (32 km) from the wildlife-management area. Survey participants completed a questionnaire and provided specimens for serologic testing. In both communities, searches for ticks were undertaken. RESULTS: Eleven cases of symptomatic ehrlichiosis were identified in the case-control study, 10 of which were in community A (attack rate, 330 per 100,000). Of 311 surveyed residents of community A, 12.5 percent had serologic evidence of past E. chaffeensis infection, as compared with 3.3 percent of 92 in community B (relative risk in community A as compared with community B, 3.9; 95 percent confidence interval, 1.2 to 12.2). The risk of infection was associated with tick bites, exposure to wildlife, golfing, and among golfers, retrieving lost golf balls from the rough. Persons who never used insect repellent were more likely to have had infection than persons who did. In community A, thousands of Lone Star ticks were found; in community B, only three ticks were found. CONCLUSIONS: The high rate of E. chaffeensis infection in community A resulted from its proximity to a wildlife reserve. When outdoor recreational activities are common and concentrations of ticks are high, outbreaks of arthropod-borne zoonoses can be anticipated.

Intravenous adenosine as first-line prehospital management of narrow-complex tachycardias by EMS personnel without direct physician control.

This study was conducted to evaluate the safety and efficacy of intravenous adenosine therapy for prehospital treatment of narrow-complex tachycardias with a presumptive field diagnosis of paroxysmal supraventricular tachycardia (PSVT) by paramedics without direct physician control. A ten-month prospective case series was designed in an urban EMS system that has paramedics operating under standing orders before physician radio contact. All patients with PSVT field diagnosis were included. Diagnosis of PSVT was made by regular, narrow-complex tachycardia with a heart rate greater than 160 beats/min by field ECG. Interpretation was performed solely by paramedics; ECG transmission was not available. In hemodynamically stable patients, vagal maneuvers were followed by intravenous placement and administration of adenosine was recommended by the manufacturer. If three adenosine boluses failed to convert the arrhythmia, patients were monitored and transported, with electrical cardioversion available. Data collection included demographic, history, medications, vital signs, and EGG tracings. Of 14 included patients, 31 were correctly diagnosed with PSVT (75.6%), with mean ventricular rate of 205 beats/min (SD 7 beats/min); one had sinus tachycardia; nine had atrial fibrillation (AF) (22%). Of the 31 cases correctly diagnosed as PSVT, 28 converted to sinus rhythm after adenosine (90.3%). Of those converted, 16 required a single dose (57.1%), nine required one additional dose (32.1%), and three required two additional doses (10.8%). None reverted to PSVT after adenosine conversion during the study period (conversion to arrival at emergency department). No significant difference in length of asystolic pause or in outcome was detected between the true PSVT cases and the AF cases receiving adenosine.(ABSTRACT TRUNCATED AT 250 WORDS)

Acid dialysate correction of metabolic alkalosis in renal failure.

Severe metabolic acidosis may occur during hemodialysis when the incorrect acid dialysis concentrate from a two-part bicarbonate dialysis system is used in an acetate dialysis machine. We deliberately applied this technique to correct severe metabolic alkalosis in a patient with chronic renal failure. Rapid correction of the metabolic alkalosis was achieved and the procedure was well tolerated.

Effects of feto-placental markers with plasma exchange in pregnancy.

To evaluate changes in feto-placental markers with plasma exchange in pregnancy, two patients at varying stages of pregnancy referred to a tertiary care hospital and requiring plasma exchange for intercurrent problems were evaluated. Alpha-fetoprotein, human chorionic gonadotropin, and free estriol were sequentially measured in the patients' plasma and in the fluid removed, thus permitting calculations of permeability rates and clearances. Despite markedly different molecular weights, all three feto-placental markers had similar permeabilities and clearances. While in both patients maternal levels of alpha-fetoprotein and human chorionic gonadotropin decreased rapidly with plasma separation and rebounded rapidly to baseline, free estriol responded differently and did not appear to decrease with therapy. Maternal levels of feto-placental markers only transiently changed with plasma exchange during pregnancy and rapidly returned to baseline with no apparent consequences to the pregnancy.

Acute plasma separation with hemodialysis equipment.

Although plasma separation has been reported to have a relatively small complication rate in large series of healthy outpatients, little attention has been directed to the evaluation of the safety and effectiveness of the therapy in acutely ill, hospitalized patients. The experience of using standard hemodialysis equipment and membrane plasma separators with 281 plasma separation treatments in 49 patients over the last 7 yr is reported and analyzed. The data reveal a 1.4% incidence of hypotension and a 0.4% incidence of hematuria in the 281 treatments--rates similar to those reported in outpatients. In addition, analysis of the diseases and patients treated over the 7 yr reported demonstrates a marked shift from immunological and hematological disorders towards neurological disorders. The data suggest that plasma separation may be easily and safely performed by any institution capable of performing acute hemodialysis.