A sustained release gel formulation of doramectin for control of lone star ticks (Acari: Ixodidae) and horn flies (Diptera: Muscidae) on cattle

A gel formulation formed by incorporating technical doramectin into a 10% hydroxypropyl methylcellulose aqueous solution was used to subcutaneously inject steers at varying dosages. Doramectin serum concentration of steers receiving 600 microg (AI)/kg body weight declined from 21.9 ppb at 0.5 wk to below detectable at 8 wk postinjection. The 1,200 microg (AI)/kg injection resulted in serum concentrations of 29.1 ppb at 0.5 wk and declined to 0.5 ppb at 8 wk postinjection. Both the 600 and 1,200 microg (AI)/kg injections provided 100% inhibition of index of fecundity (IF) in adult lone star ticks, Amblyomma americanum L. (Acari: Ixodidae) through week 8, after which inhibition declined to 79.4 and 45.3%, respectively, during the 12th week posttreatment. For steers treated at 600 microg (AI)/kg, mortality of adult horn flies, Hematobia irritans L. (Diptera: Muscidae), declined from 16.9% during week 2 to 3.1% during week 7 postinjection. The blood from steers treated at 1,200 microg (AI)/kg resulted in a similar decline in mortality of blood fed adult horn flies from 29.4% during week 1 to 4.0% during week 7. The 600 microg (AI)/kg treatment provided complete control of larval horn flies in the manure for 9 wk, whereas the 1,200 microg (AI)/kg injection gave complete control for 14 wk posttreatment. The doramectin gel formulation provided long-lasting delivery of doramectin to cattle and extended control of lone star ticks and larval horn flies. Such a simple and inexpensive formulation could be useful in tick eradication programs by reducing the frequency of gathering cattle.

Reduced interference by gray squirrels with 4-poster deer treatment bait stations by using timed-release bait

When white-tailed deer, Odocoileus virginianus, feed on corn bait dispensed by 4-poster tick control devices, they rub against paint rollers impregnated with acaricide. Gray squirrels, Sciurus carolinensis, also feed on the corn bait in the feeding troughs of 4-posters, but in doing so, leave abundant corn fragments and meal that impede the flow of uneaten corn into the troughs. Large accumulations of fragments and meal adversely affect the operation of 4-posters and their use by deer. A battery-operated closure mechanism controlled by a photo sensor was developed to block the flow of corn into the troughs during the day when squirrels are active and deer infrequently visit 4-posters. The effectiveness of the diurnal corn restriction (DCR) concept and restriction mechanism was tested in a field trial at a tick-infested site in Maryland. DCR effectively eliminated accumulation of whole corn, partially eaten corn and corn meal in corn troughs associated with squirrel feeding. At the same time, deer usage of 4-posters was not diminished.

The effect of oral contraceptives on the nitric oxide system and renal function

We have demonstrated that oral contraceptive (OC) users exhibit elevated angiotensin II levels and angiotensin II type 1 receptor expression, indicative of renin-angiotensin system (RAS) activation, yet the renal and systemic consequences are minimal, suggesting that there is increased vasodilatory activity, counteracting the effect of RAS activation. We hypothesized that the nitric oxide (NO) system would be upregulated in OC users and that this would be reflected by a blunted hemodynamic response to l-arginine infusion. All subjects were studied after a 7-day controlled sodium and protein diet. Inulin and para-aminohippurate clearance techniques were used to assess renal function. l-Arginine was infused at 100, 250, and 500 mg/kg, each over 30 min. Skin endothelial NO synthase mRNA expression was assessed by real-time PCR. While OC nonusers exhibited significant increases in effective renal plasma flow (670.8 +/- 35.6 to 816.2 +/- 59.7 ml.min(-1).1.73 m(-2)) and glomerular filtration rate (133.4 +/- 4.3 to 151.0 +/- 5.7 ml.min(-1).1.73 m(-2), P = 0.04) and declines in renal vascular resistance (81.1 +/- 6.1 to 63.5 +/- 6.2 mmHg.ml(-1).min, P = 0.001) at the lower l-arginine infusion rates, the responses in OC users were blunted. While l-arginine reduced mean arterial pressure at the 250 and 500 mg/kg doses in OC nonusers, OC users only exhibited a decrease in mean arterial pressure at the highest infusion rate. In contrast, tissue endothelial NO synthase mRNA levels were higher in the OC users (P = 0.04). In summary, these findings suggest that the NO system is upregulated by OC use in young, healthy women. Increased activity of the NO pathway may modulate the hemodynamic effects of RAS activation in OC users.

Pathogenicity of three formulations of entomopathogenic fungi for control of adult Haematobia irritans (Diptera: Muscidae)

Powder formulations of three species of entomopathogenic fungi were evaluated for their pathogenic effect upon adult horn flies, Hematobia irritans (L.) (Diptera: Muscidae). Flies were treated with conidia and blastospores of the entomopathogenic fungi Beauveria bassiana (Bals.) Vuill. (strain GHA), Metarhizium anisopliae (Metschnikoff) Sorokin (strain ESCI), and Paecilomyces fimosoroseus (Wize) Brown & Smith (strain ARSEF 3581) in the laboratory. At 4 d postexposure, flies treated with B. bassiana had an average of 98.4% mortality versus 43.5% from treatment with M. anisopliae and 13.0% from treatment with P. fiimosoroseus. At 7 d postexposure, flies treated with B. bassiana had an average of 100.0% mortality compared with 73.0% from treatment with M. anisopliae and 33.3% from treatment with P.fumosoroseus. Mean lethal time (LT50) was 2.70, 4.98, and 7.97 d for B. bassiana, M. anisopliae, and P. fiumosoroseus, respectively. Entomopathogenic fungi such as B. bassiana and M. anisopliae may have the potential for controlling populations of horn flies. These studies indicate that B. bassiana and M. anisopliae were not only pathogenic to adult horn flies, but they caused mortality in a short time.

A high frequency resonance in the responses of retinal ganglion cells to rapidly modulated stimuli: a computer model

Brisk Y-type ganglion cells in the cat retina exhibit a high frequency resonance (HFR) in their responses to large, rapidly modulated stimuli. We used a computer model to test whether negative feedback mediated by axon-bearing amacrine cells onto ganglion cells could account for the experimentally observed properties of HFRs. Temporal modulation transfer functions (tMTFs) recorded from model ganglion cells exhibited HFR peaks whose amplitude, width, and locations were qualitatively consistent with experimental data. Moreover, the wide spatial distribution of axon-mediated feedback accounted for the observed increase in HFR amplitude with stimulus size. Model phase plots were qualitatively similar to those recorded from Y ganglion cells, including an anomalous phase advance that in our model coincided with the amplification of low-order harmonics that overlapped the HFR peak. When axon-mediated feedback in the model was directed primarily to bipolar cells, whose synaptic output was graded, or else when the model was replaced with a simple cascade of linear filters, it was possible to produce large HFR peaks but the region of anomalous phase advance was always eliminated, suggesting the critical involvement of strongly non-linear feedback loops. To investigate whether HFRs might contribute to visual processing, we simulated high frequency ocular tremor by rapidly modulating a naturalistic image. Visual signals riding on top of the imposed jitter conveyed an enhanced representation of large objects. We conclude that by amplifying responses to ocular tremor, HFRs may selectively enhance the processing of large image features.

Epithelioid haemangioma in association with a deep arteriovenous malformation

Epithelioid haemangiomas are benign, vascular tumours characterized by the proliferation of epithelioid endothelial cells with abundant eosinophilic hyaline cytoplasm. We report a case of epithelioid haemangioma in association with a deep arteriovenous malformation of the subclavian artery. The association of reactive vascular proliferations with arteriovenous malformations is uncommonly reported.

Radon track imaging in CR-39 plastic detectors using confocal scanning laser microscopy

Confocal scanning laser microscopy (CSLM) has been used to provide the first images of radon track populations in two external CR-39 plastic detectors. Measurements of variables including track area distribution and estimates of the angle of track inclination (dip) derived from surface CSLM sections are presented. CSLM depth slices, combined with three-dimensional (3D) visualization techniques, provide a new, non-destructive way of examining the 2D and 3D geometry of the etched tracks within solid-state nuclear track detectors that may prove useful in complementing existing optical microscopy methods.

Distribution of horn flies on individual cows as a percentage of the total horn fly population

Twenty-three mixed-breed herd cows were phenotyped for their ability to serve as a suitable host for Haematobia irritans, the horn fly. Based upon consistent observations within the lower quartile or upper quartile of individual fly counts, four cows were phenotyped as low carriers and five cows were phenotyped as high carriers of horn flies. The cows designated as low carriers consistently carried levels of flies below the economic threshold. However, during a period of fly population explosion, low carriers harbored flies well above the economic threshold. Although the number of flies counted on these low carrying cattle increased as the population increased, the relative percentage of the population that they carried changed very little. A hypothesis is proposed to explain this observation, and future studies are suggested.

Control of Ixodes scapularis (Acari: Ixodidae) with topical self-application of permethrin by white-tailed deer inhabiting NASA, Beltsville, Maryland

We report the first successful area-wide reduction of Ixodes scapularis by using minimal amounts of permethrin self-applied by free-ranging white-tailed deer in as little as 3 y of nearly continuous treatment. The study to control all active stages of L. scapularis Say was initiated in April 1995, at the Goddard Space Flight Center, National Aeronautics and Space Administration (NASA), Beltsville, Maryland (treated location), and the Patuxent Wildlife Research Center, Laurel, Maryland (non-treated location). The locations had similar flora and fauna, and pre-treatment sampling (April to October 1995) of deer, plots, and mice for I. scapularis indicated nearly similar tick populations at both locations. After pre-treatment sampling, 4 deer '4-poster' stations were placed at NASA, while the control area received none. Ten percent permethrin, supplied to 4 roller covers on each station, was passively transferred to the head, neck, and ears of free-ranging deer feeding at the stations. This treatment resulted in elimination of adult I. scapularis on sampled deer (100% control) by the 2nd y of treatment and reductions of immature tick stages on mice. During the 3rd y of treatment, adult, nymphal, and larval questing ticks were reduced by 91-100% from sampled plots, and nymphal and larval ticks were reduced by 70-95% on sampled mice.

Pharmacokinetics of ivermectin in llamas (Lama glama)

The pharmacokinetic behaviour of ivermectin was investigated in adult llamas (Lama glama) by using high performance liquid chromatography with a lower limit of quantification of 2 ng/ml to measure its concentration in serum. Llamas were treated with one of three commercial formulations (injectable, pour-on or oral paste) at dosages recommended by the manufacturer, or with an experimental injectable sustained-release formulation. In five llamas given 1 per cent ivermectin subcutaneously at 200 microg/kg, the median peak serum concentration (Cmax) was 3 ng/ml and the area under the serum concentration-time curve (AUC) was 13.5 ng x day/ml. In six llamas treated topically with 0.5 per cent ivermedin pour-on at 500 microg/kg, Cmax was 2.5 ng/ml or less and the AUC was 7.75 ng x day/ml or less. In seven llamas with measurable concentrations of ivermedin, the median times to peak serum concentration (tmax) were six days after subcutaneous injection and seven days after treatment with the pour-on formulation. In six llamas, the serum concentration of ivermectin remained less than 2 ng/ml for 124 hours after treatment with a 1.87 per cent oral paste at 200 microg/kg. In five llamas treated subcutaneously with 25 per cent ivermectin sustained-release microspheres at 1500 microg/kg, the median Cmax was 5 ng/ml and the median AUC was 224 ng x day/ml.

Infrared frequency-modulation probing of product formation in alkyl + O2 reactions. Part IV. Reactions of propyl and butyl radicals with O2

The time-resolved production of HO2 in the Cl-initiated oxidation of iso- and n-butane is measured using continuous-wave (CW) infrared frequency modulation spectroscopy between 298 and 693 K. The yield of HO2 is determined relative to the Cl2/CH3OH/O2 system. As in studies of smaller alkanes, the branching fraction to HO2 + alkene in butyl + O2 displays a dramatic rise with increasing temperature between about 550 and 700 K (the "transition region") which is accompanied by a qualitative change in the time behavior of the HO2 production. At low temperatures the HO2 is formed promptly; a second, slower production of HO2 is responsible for the bulk of the increased yield in the transition temperature region. In contrast to reactions of smaller alkyl radicals with O2, the total HO2 yield in the butyl radical reactions appears to remain significantly below 1 up to 700 K, implying a significant role for OH-producing channels. The slower HO2 production in butane oxidation displays an apparent activation energy similar to that measured for smaller alkyl + O2 reactions, suggesting that the energetics of the HO2 elimination transition state are similar for a broad range of R + O2 systems. A combination of QCISD(T) based characterizations of the propyl and butyl + O2 potential energy surfaces and master equation based characterization of the propyl + O2 kinetics provide the framework for explanation of the experimentally observed HO2 production in Cl-initiated propane and butane oxidation. These calculations suggest that the HO2 elimination channel is similar in all reaction systems, and that hydroperoxyalkyl (QOOH) species produced by internal H-atom abstraction in RO2 can provide a path to OH formation. However, the QOOH formed by the energetically favorable 1,5 isomerization (via a six-membered ring transition state) generally experiences significant barriers (relative to the radical + O2 reactants) to the production of an oxetane + OH. In contrast, the barriers to forming OH + an oxirane or an oxolane, via 1,4 or 1,6 isomerizations, respectively, are generally below reactants.

A theoretical analysis of the reaction between propargyl and molecular oxygen

The temperature- and pressure-dependent kinetics of the reaction between propargyl and molecular oxygen have been studied with a combination of electronic structure theory, transition state theory, and the time-dependent master equation. The stationary points on the potential energy surface were located with B3LYP density functional theory. Approximate QCISD(T,Full)/6-311++G(3df,2pd) energies were obtained at these stationary points. At low temperatures the reaction is dominated by addition to the CH2 side of the propargyl radical followed by stabilization. However, addition to the CH side, which is followed by one of various possible internal rearrangements, becomes the dominant process at higher temperatures. These internal rearrangements involve a splitting of the O2 bond via the formation of 3-, 4- or 5-membered rings, with the apparent products being CH2CO + HCO. Rearrangement via the 3-membered ring is found to dominate the kinetics. Rearrangement from the CH2 addition product, via a 4-membered ring, would yield H2CO + HCCO, but the barrier to this rearrangement is too high to be kinetically significant. Other possible products require H transfers and, as a result, appear to be kinetically irrelevant. Modest variations in the energetics of a few key stationary points (most notably the entrance barrier heights) yield kinetic results that are in good agreement with the experimental results of Slagle and Gutman (I. R. Slagle and D. Gutman, Proc. Combust. Inst., 1986, 21, 875) and of Atkinson and Hudgens (D. B. Atkinson and J. W. Hudgens, J. Phys. Chem. A, 1999, 103, 4242).

A direct transition state theory based analysis of the branching in NH2 + NO

A combination of high-level quantum-chemical simulations and sophisticated transition state theory analyses is employed in a study of the temperature dependence of the N2H + OH-->HNNOH recombination reaction. The implications for the branching between N2H + OH and N2 + H2O in the NH2 + NO reaction are also explored. The transition state partition function for the N2H + OH recombination reaction is evaluated with a direct implementation of variable reaction coordinate (VRC) transition state theory (TST). The orientation dependent interaction energies are directly determined at the CAS + 1 + 2/cc-pvdz level. Corrections for basis set limitations are obtained via calculations along the cis and trans minimum energy paths employing an approximately aug-pvtz basis set. The calculated rate constant for the N2H + OH-->HNNOH recombination is found to decrease significantly with increasing temperature, in agreement with the predictions of our earlier theoretical study. Conventional transition state theory analyses, employing new coupled cluster estimates for the vibrational frequencies and energies at the saddlepoints along the NH2 + NO reaction pathway, are coupled with the VRC-TST analyses for the N2H + OH channels to provide estimates for the branching in the NH2 + NO reaction. Modest variations in the exothermicity of the reaction (1-2 kcal mol-1), and in a few of the saddlepoint energies (2-4 kcal mol-1), yield TST based predictions for the branching fraction that are in satisfactory agreement with related experimental results. The unmodified results are in reasonable agreement for higher temperatures, but predict too low a branching ratio near room temperature, as well as too steep an initial rise.

Losartan may modulate erythropoietin production

Erythropoietin (Epo) is distinct amongst haematopoietic hormones, in that it is produced remote from the bone marrow. The tissue oxygen pressure required to trigger the Epo gene under physiological conditions is uniquely sited at a restricted area in the kidney termed the critmeter. Angiotensin II (Ang II) increases sodium reabsorption and hence oxygen consumption at any given bloodflow rate; therefore, it may affect the balance of renal oxygen supply vs. demand and hence Epo production. The purpose of this study was to determine whether Epo production is modulated by the renin-angiotensin system (RAS). Twenty normal subjects on a controlled sodium and protein diet had glomerular filtration rate (GFR) and renal plasma flow (RPF)assessed by standard methods of inulin and para-aminohippurate clearance, respectively, at baseline, hourly after the administration of losartan (25 mg) and after each 30 minute period of the infusion of Ang II at doses of 0.5, 1.5 and 2.5 ng/kg/minute. The baseline GFR was 115+/-4.0 ml/minute/1.73 m2, RPF 650+/-29 ml/minute/1.73 m2 and Epo 12.4+/-0.8 U/L. In spite of a marked increase in filtration fraction (FF) with Ang II, no changes in serum Epo levels were observed at two hours(11.7+/-1.3 U/L, p=n.s. compared with baseline). After the administration of losartan, there was a variable effect on FF, but a strong correlation of the change in serum Epo concentration and the change in FF(r=0.648, p=0.002), suggesting that the RAS may modulate Epo production.

The Ivomec SR Bolus for control of Boophilus annulatus (Acari: Ixodidae) on cattle in South Texas

When Hereford heifers infested with Boophilus annulatus (Say) were treated with a single Ivomec SR Bolus, the concentration of ivermectin in the serum of the treated cattle reached a maximum of 8.8 +/- 0.9 ppb at 2 wk posttreatment. The single bolus treatment resulted in 84.4% control of standard engorging B. annulatus females on treated cattle over the 20-wk trial. Although fewer engorged ticks were collected from the sentinel heifers exposed in the treated pasture than those in the control pasture at weeks 4, 10, and 16 posttreatment, none of the differences was statistically significant. Each exposure of sentinel cattle found free-living ticks in both the treated and control pastures, indicating the infestation was not eliminated by the treatment. When the trial was repeated using two Ivomec SR Boluses/heifer, the concentration of ivermectin in the serum of the treated cattle reached a maximum level of 31.2 +/- 3.9 ppb at week 13 posttreatment. The use of two boluses/heifer resulted in 99.6% control of standard engorging B. annulatus females over the 20-wk trial. No ticks were found on sentinels placed in the treated pasture after week 9 posttreatment, an indication that the treatment had eliminated the free-living population in the treated pasture. From these studies, we conclude that a single Ivomec SR Bolus is incapable of sufficient control of B. annulatus to meet the rigid requirements of the Cattle Fever Tick Eradication Program in South Texas. Although two boluses per animal did eliminate the ticks from treated heifers and the pasture they were in, the treatment would not be sufficiently efficacious for mature cattle (>400 kg) for it to be useful in the program.

Rehabilitation of a patient with severe dentoalveolar injuries: a case report with a 10-year follow-up

This clinical report describes the emotional and physical rehabilitation of a young man. The impact of the injuries sustained and repeated failure of traditional dental treatment methods had caused the patient to become quite withdrawn. A successful outcome followed surgical placement of multiple titanium plasma-sprayed cylindrical fixtures in severely damaged dental supporting tissues to serve as intermediary abutments for complex maxillary and mandibular fixed prostheses. The loss of crestal bone during the postprosthetic years is determined. The advantages only implant dentistry could bring are identified.

Treatment of chronic granulomatous disease with nonmyeloablative conditioning and a T-cell-depleted hematopoietic allograft

BACKGROUND

The treatment of chronic granulomatous disease with conventional allogeneic hematopoietic stem-cell transplantation carries a high risk of serious complications and death. We investigated the feasibility of stem-cell transplantation without ablation of the recipient's bone marrow.

METHODS

Ten patients, five children and five adults, with chronic granulomatous disease underwent peripheral-blood stem-cell transplantation from an HLA-identical sibling. We used a nonmyeloablative conditioning regimen consisting of cyclophosphamide, fludarabine, and antithymocyte globulin. The allograft was depleted of T cells to reduce the risk of severe graft-versus-host disease. Donor lymphocytes were administered at intervals of 30 days or more after the transplantation to facilitate engraftment.

RESULTS

After a median follow-up of 17 months (range, 8 to 26), the proportion of donor neutrophils in the circulation in 8 of the 10 patients was 33 to 100 percent, a level that can be expected to provide normal host defense; in 6 the proportion was 100 percent. In two patients, graft rejection occurred. Acute graft-versus-host disease (grade II, III, or IV) developed in three of the four adult patients with engraftment, one of whom subsequently had chronic graft-versus-host disease. None of the five children had grade II, III, or IV acute graft-versus-host disease. During the follow-up period, four serious infections occurred among the patients who had engraftment. Three of the 10 recipients died. Preexisting granulomatous lesions resolved in the patients in whom transplantation was successful.

CONCLUSIONS

Nonmyeloablative conditioning followed by a T-cell-depleted hematopoietic stem-cell allograft is a feasible option for patients with chronic granulomatous disease, recurrent life-threatening infections, and an HLA-identical family donor.

Effect of oral contraceptives on the renin angiotensin system and renal function

We examined the effect of oral contraceptive (OC) usage on the renin angiotensin system (RAS) in two related experiments. In the first experiment, subjects were 34 healthy, normotensive, premenopausal women, 15 OC users and 19 OC nonusers, mean age 25 +/- 1 yr, ingesting a controlled sodium diet. We assessed arterial pressure, glomerular filtration rate, effective renal plasma flow, renal vascular resistance (RVR), and filtration fraction (FF) using inulin and p-aminohippurate clearance techniques, both at baseline and in response to the ANG II receptor blocker losartan. In the second experiment, in similar subjects, 10 OC users and 10 nonusers, we examined circulating RAS components [angiotensinogen, ANG II, aldosterone, plasma renin activity (PRA), and active renin] in response to incremental lower body negative pressure (LBNP), to determine whether renin secretion is suppressed by OC usage. OC users exhibited elevations in systolic blood pressure, RVR, and FF compared with nonusers, which were partially corrected by losartan. In the LBNP phase of the study, baseline measures of PRA, angiotensinogen, ANG II, and aldosterone were all increased in the OC group compared with the control group. Active renin levels did not differ between groups. Incremental LBNP resulted in increased circulating levels of RAS components in both groups. We conclude that the RAS is activated in women using OCs. There was no evidence that decreases in renin secretion result in normalization of the RAS as a whole.

Sickle cell crisis in the adult: chest radiographic findings and comparison with pediatric sickle cell disease

With the advent of improved therapy, an increasing proportion of individuals suffering from sickle cell disease (SCD) are surviving into adulthood. In contrast to children, little has been documented concerning the typical radiographic findings in adults presenting with sickle cell crises (SCC). We describe the chest radiographic (CXR) manifestations of adults with SCD presenting in SSC, correlated to hemoglobin (Hb) values, and compare them to those of the pediatric sickle cell population. The chest radiographs of 66 consecutive adults presenting to our emergency department complaining of symptoms consistent with acute SCC were retrospectively reviewed over a 12-month period. The radiographic findings were correlated with admission Hb values and compared with those of 50 children with known SCD presenting with SCC. Chi square analysis revealed no significant difference between the cardiovascular and bony findings in the adults and in those of the pediatric controls (p > 0.08-p > 1.0). However, one important difference in the two cohorts was that upper lobe infiltrates occurred exclusively in the pediatric group (p = 0.06). There was a statistically significant (p < 0.05) difference in cardiovascular and skeletal abnormalities between adults with Hb above and below the mean (8.2 g/dL). The radiographic features of adults presenting in acute SCCs are similar to those of children. Although the chest radiograph is often normal, in decreasing frequency, cardiovascular abnormalities, pneumonia sparing the upper lobes, and aseptic osteonecrosis of the shoulders and spine are not uncommon. There is a significant relationship, however, between cardiovascular abnormalities and Hb levels.

Angiotensin II type 1 receptor gene polymorphisms in humans: physiology and pathophysiology of the genotypes

Many studies have attempted to relate genetic variants of components of the renin-angiotensin system to complex diseases such as essential hypertension, cardiovascular disease and progressive renal failure. The angiotensin II type 1 receptor (AT1R) gene is an important example of this approach. Many polymorphisms of the AT1R gene have been identified, but the A1166-->C polymorphism has been the most extensively studied. The physiological significance of this polymorphism is uncertain because of its location in the 3'-untranslated region of the gene. The present review summarizes association studies of the AT1R gene, focusing on clinical end-points and physiological responses.

Efficacy of amitraz applied to white-tailed deer by the '4-poster' topical treatment device in controlling free-living lone star ticks (Acari: Ixodidae)

White-tailed deer treated themselves with a commercial pour-on acaricide formulation containing 2% amitraz as they fed from an ARS-patented '4-poster' topical treatment device. Whole kernel corn attracted deer to a single device placed in each of two deer-fenced pastures. In the treatment pasture, the rollers of the treatment device were charged with the acaricide, whereas the rollers of the device in the other pasture remained untreated. Deer were allowed to use the '4-posters' during periods of tick activity beginning in early to midspring and lasting through late summer to early fall for three consecutive years. Pretreatment sampling of adults and nymphs with dry-ice traps and larval masses with flip cloths showed no significant differences in population indices between the two pastures; however, after the third year of treatment, control of nymphal and adult ticks in the treated pasture was 91.9 and 93.7%, respectively, when compared with the untreated pasture. Control of larval masses increased from 68.4% in year 1 to 96.4% in year 2, but declined to 88.0% in year 3, probably because of the presence of feral hogs. This study demonstrated that application of amitraz to white-tailed deer through free-choice interaction with a '4-poster' device significantly reduced the abundance of free-living lone star ticks in a deer-fenced experimental pasture. Moreover, the yearly pattern of incremental increases in control and the final percentage control values for all three parasitic life stages in this topical application study were similar in magnitude to that observed in a previously conducted study in which the systemic acaricide ivermectin was used to reduce populations of free-living ticks by controlling ticks on deer.

Urinary incontinence: a classification system and treatment protocols for the primary care provider

PURPOSE

To provide nurse practitioners (NPs) with an objective system for classification of urinary incontinence and protocols for treating the condition in the primary care setting.

DATA SOURCE

Clinical practice guidelines and the author's clinical experience.

CONCLUSIONS

By using tables of classifications of urinary incontinence, management strategies, and protocols, NPs can successfully manage mild urinary incontinence in primary care settings in a cost-effective manner.

IMPLICATIONS FOR PRACTICE

A thorough history and objective classification of the severity of incontinence provides the framework for treating urinary incontinence in a methodical and effective manner.

2,2'-Anhydro-4'-thionucleosides: precursors for 2'-azido- and 2'-chloro-4'-thionucleosides and for a novel thiolane to thietane rearrangement

2,2'-Anhydro-4'-thio-beta- and alpha-nucleosides 9 and 10 have been prepared by an in situ 4-thio-1,2-glycal addition route. They undergo ring-opening by azide or chloride ion to give, after deprotection, the 2'-substituted-4'-thionucleosides 13 and 14, whereas reactions with cyanide or fluoride sources lead to the unsaturated nucleosides 17 or 18, depending upon conditions. An unexpected and clean rearrangement to the thietane 23 occurs on treatment of uracil derivative 20 with DAST.

Angiotensin II type 1 receptor gene polymorphism and the response to hyperglycemia in early type 1 diabetes

Recent studies suggest that there is an association between the A1166-->C polymorphism of the angiotensin II type 1 receptor (AGT1R), glycemic control, and the risk of diabetic nephropathy in subjects with type 1 diabetes. Because hypertension and renal hemodynamic function are also related to the risk of diabetic nephropathy and because hyperglycemia can activate the renin angiotensin system, we sought to determine if there is an association between the AGT1R polymorphism, baseline renal and peripheral hemodynamic function, and pressor response to high glucose in subjects with early uncomplicated type 1 diabetes. There were 39 diabetic subjects genotyped for the AGT1R polymorphism by polymerase chain reaction and segregated into 2 groups: those with and those without the C1166 allele (AA and AC/CC). The average age was 27 +/- 1 years, and the mean duration of diabetes was 3.5 +/- 0.6 years. HbA(1c) values were <10% in all subjects and were similar in the 2 groups (8.2 +/- 0.3 vs. 9.1 +/- 0.4%). After a 7-day controlled diet (150 mmol sodium, 1.5-2.0 g x kg(-1) x day(-1) protein), renal hemodynamic function was assessed by inulin and para-aminohippurate clearance during clamped euglycemic conditions (4-6 mmol/l). Mean values for glomerular filtration rates did not differ between groups during euglycemia. In contrast, mean values for renal plasma flow and renal blood flow were significantly greater in the AC/CC group compared with the AA group. Values for mean arterial pressure were similar in the 2 groups, whereas renal vascular resistance was significantly reduced in the AC/CC group. In 20 subjects (10 from each genotype subgroup), hemodynamic function was assessed on a second occasion during controlled clamped hyperglycemia (9-11 mmol/l) after a similar preparatory period. In response to high glucose, plasma renin activity increased in both genotype groups to the same extent, but a pressor response was noted only in subjects with the C1166 allele. Mean arterial pressure increased significantly in the AC/CC subgroup and remained unchanged in the AA subgroup. We conclude that there is an association between the AGT1R A1166-->C polymorphism and renal hemodynamic function in early type 1 diabetes. But more importantly, the pressor response to hyperglycemia is augmented in those diabetic patients with the C1166 allele and may represent a factor that predisposes them to renal injury during periods of inadequate glucose control.