Universal use of surgical masks is tolerated and prevents respiratory viral infection in stem cell transplant recipients

Prevention of respiratory viral infection in stem cell transplant patients is important due to its high risk of adverse outcome. This single-centre, mixed methods study, conducted before the severe acute respiratory syndrome coronavirus-2 pandemic, explored the barriers and facilitators to a policy of universal mask use by visitors and healthcare workers, and examined the impact of the first year of introduction of the policy on respiratory viral infection rates compared with preceding years, adjusted for overall incidence. Education around universal mask use was highlighted as being particularly important in policy implementation. A significant decrease in respiratory viral infection was observed following introduction.

Energy of the quasi-free electron in H2, D2, and O2: Probing intermolecular potentials within the local Wigner-Seitz model

We present for the first time the quasi-free electron energy V0(ρ) for H2, D2, and O2 from gas to liquid densities, on noncritical isotherms and on a near critical isotherm in each fluid. These data illustrate the ability of field enhanced photoemission (FEP) to determine V0(ρ) accurately in strongly absorbing fluids (e.g., O2) and fluids with extremely low critical temperatures (e.g., H2 and D2). We also show that the isotropic local Wigner-Seitz model for V0(ρ)--when coupled with thermodynamic data for the fluid--can yield optimized parameters for intermolecular potentials, as well as zero kinetic energy electron scattering lengths.

Epithelial-specific A2B adenosine receptor signaling protects the colonic epithelial barrier during acute colitis

Central to inflammatory bowel disease (IBD) pathogenesis is loss of mucosal barrier function. Emerging evidence implicates extracellular adenosine signaling in attenuating mucosal inflammation. We hypothesized that adenosine-mediated protection from intestinal barrier dysfunction involves tissue-specific signaling through the A2B adenosine receptor (Adora2b) at the intestinal mucosal surface. To address this hypothesis, we combined pharmacologic studies and studies in mice with global or tissue-specific deletion of the Adora2b receptor. Adora2b(-/-) mice experienced a significantly heightened severity of colitis, associated with a more acute onset of disease and loss of intestinal epithelial barrier function. Comparison of mice with Adora2b deletion on vascular endothelial cells (Adora2b(fl/fl)VeCadCre(+)) or intestinal epithelia (Adora2b(fl/fl)VillinCre(+)) revealed a selective role for epithelial Adora2b signaling in attenuating colonic inflammation. In vitro studies with Adora2b knockdown in intestinal epithelial cultures or pharmacologic studies highlighted Adora2b-driven phosphorylation of vasodilator-stimulated phosphoprotein (VASP) as a specific barrier repair response. Similarly, in vivo studies in genetic mouse models or treatment studies with an Adora2b agonist (BAY 60-6583) recapitulate these findings. Taken together, our results suggest that intestinal epithelial Adora2b signaling provides protection during intestinal inflammation via enhancing mucosal barrier responses.

A stochastic mathematical model of the within-herd transmission dynamics of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV): fade-out and persistence

A stochastic, mathematical model of a farrow-finish pig herd was developed and used to investigate the within-herd transmission dynamics of PRRSV, and to examine patterns of on-farm persistence and fade-out. The model was structured to represent the management of a typical European pig herd. Three parameters determining the natural history of infection were derived from the literature. Transmission parameters were chosen using PRRSV antibody data from a cross-sectional study of 103 pig herds (Evans et al., 2008). The seroprevalence by age was generated from the model at 21-day intervals and was compared to the cross-sectional field data using log-likelihood, accounting for the accuracy of the ELISA test used. The model was run for various isolation practices of purchased gilts, contact structure, herd size and the frequency of re-introduction of infectious gilts. The time-dependent log-likelihood patterns varied between herds in a similar way to patterns observed from serological values from the 103 farms. Essentially they indicated two patterns of seroprevalence: herds in which PRRSV was stably persistent, and herds in which PRRSV was unstable, either recently introduced or recently faded-out. With a herd size of 327 sows with identical management, fade-out of virus occurred within 4 weeks in 21.9% of simulations. Without isolation of gilts from sows, fade-out within 250 days decreased from 81.6% to 14.3% and for herd sizes of 75, 150, 300 and 600, the probability of persistence of virus for >1200 days was 4%, 13.4%, 20.4% and 18.2%, respectively. Introduction of virus at a rate of approximately 0.37 times per year resulted in virus persisting for >1200 days in 32.4% of simulations, compared with 17.6% for no re-introduction. Fade-out of virus was most likely to occur within breeding females before virus reached young stock. Persistence was more likely once PRRSV was present in piglets which in turn infected rearing-pigs. The probability of persistence was higher with increased herd size, increased contact between different age groups and increased re-introduction of infectious gilts. The ability of the model to capture the variability in cross-sectional, age-related serological patterns suggests that the processes of re-introduction, persistence and fade-out of PRRSV play critical roles in PRRSV epidemiology. The potential importance to pig production and transmission of virus between herds is discussed.

Surface soil acidity and fertility in the central-western wheatbelt of New South Wales

Documentation of the chemical fertility status of the soils is sparse for the western and central-western wheatbelt of New South Wales, Australia. We examined properties of the surface soils (0–10 cm) from central-western NSW by collating two published and nine unpublished datasets of soil analyses representing about 2800 soil samples. The emphasis was on the red soils used extensively for cropping. The surface soils of central-western NSW have low phosphorus (47% of soils) and sulfur (70% of soils <5 mg S/kg using KCl-40 analysis) status and commonly have organic carbon contents of about 1%. Surface soil acidity was a substantial problem with 56% of soils (0–10 cm) having a pHCa <5.0. Sodic and dispersive soils are also of concern in this area and these soils have received little attention or research. Approximately 5% of surface (0–10 cm) soils had an exchangeable sodium percentage of ≥6% (sodic). Salinity of surface soils was of minor significance compared with other soil problems in the area, although isolated areas occur. These results indicated that lime applications in this area are likely to benefit crop and pasture production. Additional use of phosphorus and sulfur fertilisers and agricultural practices which increase or maintain organic carbon will also need to be adopted to improve pasture and crop production. The use of gypsum and/or lime on sodic soils may also need to be addressed. As a priority, we suggest that the benefits of lime application to crop yield be examined. The application of lime to the 0–10 cm soil depth should ultimately arrest acidification of the subsurface soil (10–20 cm depth) through downward movement of the lime effect. Further examination of gypsum applications to dispersive sodic soils and the evaluation of sulfur deficiency in the field for pastures and canola are also priority areas of likely agricultural relevance.

Residual effects from lime application on soil pH, rhizobial population and crop productivity in dryland farming systems of central New South Wales

A mildly acidic (pHCa 4.79, 0–10 cm depth) red-brown earth soil (Chromosol) at Condobolin in central-western New South Wales was cultivated and limed (once only) at six rates (range 0–4 t/ha) and sown with field peas (Pisum sativumL.) with and without inoculation (once only) with Rhizobium leguminosarum bv. viciae – the rhizobium for peas. The soil already contained a very small population of pea rhizobia (<4 per g soil). The experiment embraced two parallel rotations, each over 4 years: (1) year 1, inoculated peas; year 2, wheat; year 3, wheat; year 4, uninoculated peas; and (2) year 1, inoculated peas; year 2, wheat; year 3, inoculated chickpeas; year 4, uninoculated peas. The objectives of the work were to establish whether liming had any immediate and residual benefits for rhizobia and plants and, if so, to determine if the two events were linked. Liming had an immediate effect on soil pH (0–10 cm depth). Increases in pH were greater per unit of lime at lower rates of application than at higher rates. Although lime effects existed for the duration of the experiment (four seasons of cropping), there was a small decline in soil pH over time (mean decline in unlimed plots 0.16 pHCa units, mean decline in limed plots 0.47 pHCa units). In the first year (pea crop), there was a very large and highly significant response to inoculation on populations of rhizobia in soil and rhizosphere. The number of rhizobia that occurred naturally in uninoculated plots increased rapidly in high-lime plots until, by the third year, they were substantial and, by the fourth year, equal to those in the inoculated treatment. By the end of the experiment, the mean population of rhizobia in the 4 t/ha lime treatment was 7250 per g soil, compared with <4 rhizobia per g in the nil lime treatment. It was noteworthy that, in those years in the rotations when peas were not grown, populations of R. leguminosarum bv. viciae were sustained by their ability to colonise the rhizospheres of wheat and chickpea. In the first pea crop, eight parameters of plant production responded overwhelmingly to inoculation, while there was an underlying response to liming in two of those parameters. The positive effect of inoculation on peas in the first year carried over to the wheat crop of the second year, which was interpreted as a consequence of increased soil N in the inoculated plots. By the third and fourth years, soil populations of pea rhizobia in the plus inoculation and minus inoculation treatments were approximately equal, and inoculation was no longer a determinant of crop production. On the other hand, application of lime, which had only an underlying effect on pea production in the first year, significantly enhanced several parameters of the symbiosis and growth of the chickpea and pea crops, including legume nodulation and percentage nitrogen in the seed. R. leguminosarum bv. viciae, legumes and cereals each responded differently to increasing rates of lime application. Populations of rhizobia in soil and plant rhizospheres increased with each additional rate of liming. Legume productivity responded to additional lime up to 2 t/ha. There was no significant evidence that liming per se had any effect at any time on wheat production. The practical implications of these results are discussed.

Pasture and sheep responses to lime application in a grazing experiment in a high-rainfall area, south-eastern Australia. I. Pasture production

‘Managing Acid Soils Through Efficient Rotations (MASTER)’ is a long-term pasture–crop rotation experiment commenced in 1992. One of the objectives was to demonstrate the extent of crop, pasture, and animal responses to lime on a typical acidic soil in the 500–800 mm rainfall zone in south-eastern Australia. Two types of pastures (perennial v. annual pastures) with or without lime application were established in 1992. This paper presents the results of the pasture dry matter (DM) responses to lime application over 6 years from 1992 to 1997. Results showed that both perennial and annual pastures responded positively to lime on a highly acidic soil on the south-west slopes of New South Wales. Averaged across pasture types and 5 growing seasons, the limed pastures produced 18% more pasture DM (520 kg/ha, P < 0.05) than the unlimed pastures. Significant responses to lime were detected on perennial pastures (610 kg DM/ha, P < 0.05), but not on annual pastures, although the limed annual pastures produced more DM (420 kg/ha, P = 0.20) than the unlimed annual pastures. There was a large seasonal variation in pasture growth rate with the significant lime responses in winter and spring on both perennial pastures (P < 0.05) and annual pastures (P < 0.10 in winter and P < 0.05 in spring), but no responses in autumn and summer on either perennial or annual pastures. The extra growth in winter is of importance as winter is the period when feed is normally inadequate and limits stocking rates. It is recommended that perennial-based pastures should be promoted for the purposes of productivity, in terms of increasing pasture production and improving feed quality, and for the environmental benefits in terms of alleviating the soil acidity problem and reducing the risk of dryland salinity in the high-rainfall zone in south-eastern Australia.

Effect of soil acidity and liming on lucerne and following crops in central-western New South Wales

On some of the lighter textured soils in the wheatbelt of central-western New South Wales near Dubbo, soil acidity is a major problem, and lucerne (Medicago sativa) often establishes and grows poorly. We selected a site with a surface soil pHCa of 4.4 and an exchangeable aluminium of 0.4 cmol(+)/kg, which was also acidic down the soil profile. Experimental plots of 4 application rates of lime (nil, 1, 2 and 3 t/ha) in 4 replications were established. The site was limed in 1990 and lucerne sown in May 1991. Over the next 6 years the trial was periodically grazed with sheep, and lucerne regrowth and stand density were monitored. In October 1997, the lucerne was removed and 3 crops of varying acid tolerance (wheat, barley and canola) were sown as split plots in both 1998 and 1999. Lucerne density was higher in the limed plots compared with the unlimed treatment, and this difference persisted for 6 years. Dry matter production of lucerne was increased by lime applied at rates up to 2 t/ha. All 3 crops sown after the lucerne phase responded to lime applied 8 and/or 9 years earlier. The responses were attributed to the strong residual effect of the lime in the 0–10 cm soil layer, to smaller improvements in the 10–20 cm zone (possibly due to the movement of lime down the soil profile over the 7 years before the date of measurement) and to carry over effects of nitrogen fixation by the lucerne into the cropping phase. The protein content of the wheat grain was increased concurrently with grain yield due to the previous liming and resultant legume nitrogen effects. The results support the application of lime to improve the productivity of lucerne and subsequent crops, even when the soil is acidic to depths below the cultivation layer.

Energy of the Quasi-Free Electron in Supercritical Krypton near the Critical Point

Field ionization measurements of high-n CH(3)I and C(2)H(5)I Rydberg states doped into krypton are presented as a function of krypton number density along the critical isotherm. These data exhibit a decrease in the krypton-induced shift of the dopant ionization energy near the critical point. This change in shift is modeled to within +/-0.2% of experiment using a theory that accounts for the polarization of krypton by the dopant ion, the polarization of krypton by the quasi-free electron that arises from field ionization of the dopant, and the zero point kinetic energy of the free electron. The overall decrease in the shift of the dopant ionization energy near the critical point of krypton, which is a factor of 2 larger than that observed in argon, is dominated by the increase in the zero point kinetic energy of the quasi-free electron.

Effects of lime on the botanical composition of pasture over nine years in a field experiment on the south-western slopes of New South Wales

Two permanent pastures (annual pasture v. perennial pasture) were established in 1992 as part of the long-term field experiment, MASTER — Managing Acid Soils Through Efficient Rotations. The primary objective of the experiment was to develop an agricultural system that is economically viable and environmentally sustainable on the highly acidic soils in south-eastern Australia. This paper reports on the effects of lime on the botanical composition changes of annual and perennial pastures over 9 years. In general, lime increased the proportion of the desirable species, such as phalaris (Phalaris aquatica) in perennial pasture and subterranean clover (Trifolium subterraneum) in annual pastures, and decreased the proportion of the undesirable species, such as Vulpia spp., in both annual and perennial pastures, ultimately improving the quality of feed-on-offer to animals. As a result, the limed pastures carried 24% more sheep than the unlimed pastures, while maintaining individual animal performance similar for both limed and unlimed pastures. The phalaris-based perennial pasture was more stable in terms of maintaining the sown species than the annual pasture. Lime improved the persistence of phalaris and the longevity of the phalaris-based pasture should be at least 10 years. Lime changed the direction of plant succession of annual pastures. Without lime, Vulpia spp. gradually became more dominant while ryegrass and subterranean clover became less dominant in annual pastures. With lime, barley grass (Hordeum leporinum) gradually invaded the sward at the expense of ryegrass, thus reducing the benefits of lime, but this effect was less for the perennial pastures than for annual pastures. Liming perennial pastures should be more beneficial than liming annual pastures because of the beneficial effects on pasture composition. In addition, previously published work reported that liming perennial pastures improved sustainability through better use of water and nitrogen.

Phosphorus fertiliser placement for lupins in southern New South Wales

Research in Western Australia and South Australia indicated that fertiliser phosphorus (P) banded below the seed of narrow leaf lupin (Lupinus angustifolius L.) at sowing was a more effective method of applying P�fertiliser than the usual placement of P with the seed. This technology has not been investigated in southern New South Wales where lupins have been known to be unresponsive to fertiliser P.We conducted 4 field experiments to examine the effect on lupin yield of applying 6 rates of P (0, 5, 10, 15, 20 and 40 kg/ha) either by placement with or below the seed. To further test responsiveness to P, an additional set of treatments was used; applying P at 40 kg/ha before sowing and then placing additional P below the seed at the 6�rates of application. The grain yield of lupin was increased by P application at all sites, despite the medium to high P�status of 3 of the 4 sites used in these experiments. However, the technique of banding P fertiliser below the seed depth rather than placing it in direct seed contact had only a small advantage in grain yield responsiveness to applied fertiliser P (P = 0.09). Fitted response curves indicated that when P was applied at 15 kg/ha, grain yield increased by 60 kg/ha at one site and 30 kg/ha at the other 3 sites, if P was deep-placed rather than applied in seed contact. This advantage of deep placement of P fertiliser was much smaller than has been reported in Western Australia.Placement of P below the seed of lupin when sown on the red earth and red-brown earth soils of southern New South Wales slightly enhanced the availability of fertiliser P. This applied even when sowing was quite shallow (2–3�cm), provided recommended rates of P fertiliser were used at conventional row spacing (17 cm). Separation of seed and fertiliser to avoid reduced germination may be an advantage when using double row spacing and higher P�application rates.

Evaluation of extracorporeal shock wave therapy in Peyronie's disease

OBJECTIVES

To evaluate the results of extracorporeal shock wave therapy (ESWT) in patients with Peyronie's disease.

METHODS

This study included 42 patients (mean age 55.4 years, range 32 to 72, SD 9.92) with Peyronie's disease. The mean duration of disease was 16.5 months (range 3 to 60, SD 13.31). Before treatment, the degree of angulation was assessed artificially by injection of 10 to 20 microg alprostadil, and Polaroid photographs were taken. Patients were also questioned about pain on erection, whether sexual intercourse was possible, and the quality of erections. All were initially treated with three sessions of ESWT (3000 shock waves). After three sessions, patients who believed that improvement had resulted or who wanted to undergo additional treatment went on to have further sessions. The mean duration of follow-up was 5.9 months (range 2 to 18, SD 4.4), after which the results were analyzed.

RESULTS

Those who believed that improvement in angulation had resulted were asked to provide Polaroid photographs to assess the improvement objectively. Six (14%) said that they had excellent results, 21 (50%) had significant improvement, 7 (17%) had slight improvement, and 8 (19%) had no change. Of the 25 who had pain on erection before treatment, 21 (84%) reported complete or near complete relief after treatment. Five patients said that the quality of the erections had improved after treatment. Eight patients complained of mild and one of severe pain during or immediately after treatment; 2 of these 9 patients had both pain and bruising.

CONCLUSIONS

The initial results with ESWT are promising, with minimal complications. The long-term results need to be evaluated.

Effects of dexamethasone on antigen-induced airway eosinophilia and M(2) receptor dysfunction

In antigen-challenged guinea pigs, airway hyperreactivity is due to recruitment of eosinophils to the airway nerves and dysfunction of M(2) muscarinic receptors. M(2) receptor dysfunction is caused by eosinophil major basic protein, which is an allosteric antagonist at the receptor. Because glucocorticoids inhibit airway hyperreactivity in humans and in animal models of asthma, we tested whether dexamethasone treatment (6 microg. kg(-)(1). d(-)(1) for 3 d, intraperitoneal) before antigen challenge prevents M(2) receptor dysfunction and airway hyperreactivity. Guinea pigs were sensitized to ovalbumin via intraperitoneal injections, and were challenged with ovalbumin via inhalation. Twenty-four hours later, hyperreactivity and M(2) receptor function were tested. Antigen-challenged animals were hyperreactive to vagal stimulation, and demonstrated loss of M(2) receptor function. Dexamethasone pretreatment prevented hyperreactivity and M(2) receptor dysfunction in antigen-challenged guinea pigs. Antigen challenge resulted in recruitment of eosinophils to the airways and to the airway nerves. Dexamethasone prevented recruitment of eosinophils to the airway nerves but did not affect total eosinophil influx into the airways. These results demonstrate that dexamethasone prevents antigen-induced hyperreactivity by protecting neuronal M(2) muscarinic receptors from antagonism by eosinophil major basic protein, and this protective mechanism appears to be by specifically inhibiting eosinophil recruitment to the airway nerves.

Pre-reactive complexes in mixtures of water vapour with halogens: characterisation of H2O...ClF and H2O...F2 by a combination of rotational spectroscopy and ab initio calculations

Complexes H2O...ClF and H2O...F2 were detected by means of their ground-state rotational spectra in mixtures of water vapour with chlorine monofluoride and difluorine, respectively. A fast-mixing nozzle was used in conjunction with a pulsed-jet, Fourier-transform microwave spectrometer to preclude the vigorous chemical reaction that these dihalogen species undergo with water. The ground-state spectra of seven isotopomers (H2 16O...35ClF, H2 16O...ClF, H2 18O...35ClF, D2 16O... 35ClF, D2 16O...37ClF, HDO...35ClF and HDO...37ClF) of the ClF complex and five isotopomers (H2O...F2, H2 18O...F2, D2O...F2, D2 18O...Fi and HDO...F2) of the F2 complex were analysed to yield rotational constants, quartic centrifugal distortion constants and nuclear hyperfine coupling constants. These spectroscopic constants were interpreted with the aid of simple models of the complexes to give effective geometries and intermolecular stretching force constants. Isotopic substitution showed that in each complex the H2O molecule acts as the electron donor and either CIF or F2 acts as the electron acceptor, with nuclei in the order H2O...ClF or H2O...F2. For H2O...ClF, the angle phi between the bisector of the HOH angle and the O...Cl internuclear line has the value 58.9(16)degrees, while the distance r(O...Cl)= 2.6081(23) A. The corresponding quantities for H2O...F2 are phi = 48.5(21)degrees and r(O...Fi) = 2.7480(27) A, where Fi indicates the inner F atom. The potential energy V(phi) as a function of the angle phi was obtained from ab initio calculations at the aug-cc-pVDZ/MP2 level of theory for each complex by carrying out geometry optimisations at fixed values of phi in the range +/-80degrees. The global minimum corresponded to a complex of Cs symmetry with a pyramidal configuration at O in each. The function V(phi) was of the double-minimum type in each case with equilibrium values phie = +/-55.8degrees and +/-40.5degrees for H2O...ClF and H2O...F2, respectively. The barrier at the planar C2v conformation was V0= 174cm(-1) for H2O...ClF and 7cm(-1) for H2O...F2. For the latter complex, the zero-point energy level lies above the top of the barrier.

Crop responses to lime in long-term pasture-crop rotations in a high rainfall area in south-eastern Australia

A long-term trial, known as ‘managing acid soils through efficient rotations’ (MASTER), commenced in 1992 to develop and demonstrate a cropping system that is economically viable on the highly acid soils of the traditional permanent pasture region in south-eastern Australia, so that their fertility is sustained or improved. There were 2 permanent pasture systems and 2 pasture–crop rotations, each with and without lime. This paper reports the effect of lime on crop production over the first cycle (6 years). On annual pasture–crop rotations, lime significantly increased the dry matter production at anthesis and grain yields of wheat (cv. Dollarbird) compared with the unlimed treatments. Averaged across years from 1992 to 1997 (excluding the severe drought year 1994), wheat crops produced 1.6 t/ha more grain on the limed treatments than on the unlimed treatments (3.6 v. 2.0 t/ha). On perennial pasture–crop rotations, the lime effects varied with crops grown at each phase and year. For example, despite being tolerant of acidity, oats (cv. Yarran) responded to lime in 1996. Likewise, triticale (cv. Abacus) responded to lime in 1997. Wheat (cv. Dollarbird) that is moderately tolerant to acidity responded to lime in phase 6 from 1992 to 1997 excluding 1994 (3.5 v. 1.7 t/ha). Acid-tolerant wheat varieties, triticale, and narrow-leaf lupins are considered the most viable crops for the soil and climatic conditions encountered in this high rainfall (5000—800 mm per annum) area of south-eastern Australia.

Substance P-induced airway hyperreactivity is mediated by neuronal M(2) receptor dysfunction

Neuronal muscarinic (M(2)) receptors inhibit release of acetylcholine from the vagus nerves. Hyperreactivity in antigen-challenged guinea pigs is due to blockade of these M(2) autoreceptors by eosinophil major basic protein (MBP) increasing the release of acetylcholine. In vivo, substance P-induced hyperactivity is vagally mediated. Because substance P induces eosinophil degranulation, we tested whether substance P-induced hyperreactivity is mediated by release of MBP and neuronal M(2) receptor dysfunction. Pathogen-free guinea pigs were anesthetized and ventilated. Thirty minutes after intravenous administration of [Sar(9),Met(O(2))(11)]- substance P, guinea pigs were hyperreactive to vagal stimulation and M(2) receptors were dysfunctional. The depletion of inflammatory cells with cyclophosphamide or the administration of an MBP antibody or a neurokinin-1 (NK(1)) receptor antagonist (SR-140333) all prevented substance P-induced M(2) dysfunction and hyperreactivity. Intravenous heparin acutely reversed M(2) receptor dysfunction and hyperreactivity. Thus substance P releases MBP from eosinophils resident in the lungs by stimulating NK(1) receptors. Substance P-induced hyperreactivity is mediated by blockade of inhibitory neuronal M(2) receptors by MBP, resulting in increased release of acetylcholine.

A student-directed community project to support sexually abused women veterans suffering from post-traumatic stress disorder

While awareness of post-traumatic stress disorder (PTSD) and sexual abuse continues to grow, it has only been during the past few years that the military has realized the prevalence and impact of sexual abuse inflicted upon women while on active military duty. Though Veteran Administration (VA) agencies throughout the United States have given concerted attention to this problem, published resources specific to PTSD and military sexual abuse have been limited. In this article the authors present the results of a 2(1/2)-year endeavor to address the problem of PTSD and military sexual abuse at the Tulsa VA Outpatient Clinic. The project started with a research study and the subsequent initiation of a PTSD women veterans support group, and culminated in the development of resource manuals for both professional staff and women veterans.

Antigen-induced hyperreactivity to histamine: role of the vagus nerves and eosinophils

M2 muscarinic receptors limit acetylcholine release from the pulmonary parasympathetic nerves. M2 receptors are dysfunctional in antigen-challenged guinea pigs, causing increased vagally mediated bronchoconstriction. Dysfunction of these M2 receptors is due to eosinophil major basic protein, which is an antagonist for M2 receptors. Histamine-induced bronchoconstriction is composed of a vagal reflex in addition to its direct effect on airway smooth muscle. Because hyperreactivity to histamine is seen in antigen-challenged animals, we hypothesized that hyperreactivity to histamine may be due to increased vagally mediated bronchoconstriction caused by dysfunction of M2 receptors. In anesthetized, antigen-challenged guinea pigs, histamine-induced bronchoconstriction was greater than that in control guinea pigs. After vagotomy or atropine treatment, the response to histamine in antigen-challenged animals was the same as that in control animals. In antigen-challenged animals, blockade of eosinophil influx into the airways or neutralization of eosinophil major basic protein prevented the development of hyperreactivity to histamine. Thus hyperreactivity to histamine in antigen-challenged guinea pigs is vagally mediated and dependent on eosinophil major basic protein.

Pretreatment with antibody to eosinophil major basic protein prevents hyperresponsiveness by protecting neuronal M2 muscarinic receptors in antigen-challenged guinea pigs

In antigen-challenged guinea pigs there is recruitment of eosinophils into the lungs and to airway nerves, decreased function of inhibitory M2 muscarinic autoreceptors on parasympathetic nerves in the lungs, and airway hyperresponsiveness. A rabbit antibody to guinea pig eosinophil major basic protein was used to determine whether M2 muscarinic receptor dysfunction, and the subsequent hyperresponsiveness, are due to antagonism of the M2 receptor by eosinophil major basic protein. Guinea pigs were sensitized, challenged with ovalbumin and hyperresponsiveness, and M2 receptor function tested 24 h later with the muscarinic agonist pilocarpine. Antigen-challenged guinea pigs were hyperresponsive to electrical stimulation of the vagus nerves compared with controls. Likewise, loss of M2 receptor function was demonstrated since the agonist pilocarpine inhibited vagally-induced bronchoconstriction in control but not challenged animals. Pretreatment with rabbit antibody to guinea pig eosinophil major basic protein prevented hyperresponsiveness, and protected M2 receptor function in the antigen-challenged animals without inhibiting eosinophil accumulation in the lungs or around the nerves. Thus, hyperresponsiveness is a result of inhibition of neuronal M2 muscarinic receptor function by eosinophil major basic protein in antigen-challenged guinea pigs.

Stingray hickey

A large number of injuries from stingrays are reported each year in the United States. Usually these injuries are inflicted by the stingray's tail, after the resting stingray is stepped on. The tail has a stinger that can cause puncture wounds with envenomation. We report a case in which an injury from a stingray was due to its bite.

Supporting future surgical innovation. Lung transplantation as a case study

OBJECTIVE

Using lung transplantation as a case study, this article addressed the problem of supporting innovative clinical surgery in an era of increasing pressures for cost containment.

SUMMARY BACKGROUND DATA

After sporadic attempts at lung transplantation during the 1960s and 1970s, its clinical development began in earnest during the early 1980s. As a result of a wide range of incremental advances, the results have improved significantly. The Health Care Financing Administration, however, has not yet issued a national policy covering lung transplants and has left the coverage decision to the discretion of its regional contractors.

METHODS

The authors surveyed the major commercial insurers, the Blue Cross Blue Shield Association, and a sample of Medicare intermediaries to evaluate the coverage of lung transplantation. They also interviewed the National Heart, Lung, and Blood Institute and industrial firms about their support for clinical research.

RESULTS

Government and industry funding were limited, and the development and assessment of lung transplants have been financed predominantly by academic institutions through cross-subsidization from patient care and teaching funds. The major private payers and Blue Cross Blue Shield decided to cover this procedure in the early 1990s. Coverage decisions by Medicare intermediaries, however, revealed considerable variability. Moreover, the absence of a specific diagnosis-related group for lung transplants had considerable consequences for institutions in all-payer states, in which payments appeared to be considerably lower than the mean costs of a transplant procedure (about $110,000).

CONCLUSIONS

This analysis indicated that there was a growing disparity between the increasing demand for outcomes data about new procedures and the limited resources available for supporting the development and assessment of new operations. It this disparity is not addressed, the rate of surgical innovation may be jeopardized, and timely outcomes data may not be acquired. It was concluded that provisional coverage within a predetermined research protocol may be a promising mechanism to remedy this situation, providing timely assessment of new procedures before widespread application.

Activation of lamina propria T cells induces crypt epithelial proliferation and goblet cell depletion in cultured human fetal colon

An organ culture model has been used to study the effects of T cell activation in the human colon. Lamina propria T cells in explant cultures of human fetal colon (11 to 23 weeks gestation) were activated in situ using pokeweed mitogen or an anti-CD3 monoclonal antibody, and compared with unstimulated controls. After three days of culture, there was a two to four-fold increase in crypt epithelial cell proliferation in T cell stimulated explants of more than 15 weeks gestation, associated with a fall in crypt goblet cell numbers of up to 20-fold. By three days, the surface epithelium of stimulated explants appeared thin with loss of goblet cells, and by day 7, severe and extensive mucosal damage was observed by light and electron microscopy. These changes did not occur in control cultures and explants deficient in T cells (less than 16 weeks gestation), and were inhibited by cyclosporin A. These experiments indicate that the increase in epithelial cell proliferation and accompanying goblet cell depletion observed in colorectal crypts in chronic inflammatory bowel disease may be mediated by activated T cells.

Nursing salaries: a new strategy

Salary inconsistencies in the nursing department of the Mecklenburg Medical Group were becoming a significant problem. This case study explains how the group implemented a system to bring nurses' salaries in line with the rest of the community.

Three hundred sixty-five days post-HMO

Carolina Medical Care was conceived as a physician-owned HMO. Two-and-a-half years later, it was declared insolvent and shut down. As a founding member of the HMO, a third of its 15,000 patients were capitated to the Mecklenburg Medical Group. This case study examines the efforts to keep those patients following dissolution of the HMO.

Screening impotence by home nocturnal tumescence self-monitoring

Twenty subjects complaining of impotence were assessed using nocturnal penile tumescence (NPT), neurological, vascular and hormonal analysis. Subjects undertook NPT in both home and hospital environments: 10 hospital first and 10 home first. There were high levels of agreement between diagnosis using NPT in the two conditions and diagnosis from the physiological tests. There was a high correlation of frequency of erections between the home and hospital conditions, together with a high consecutive night reliability when using the monitor in the home condition (r = .94, p = .001).

Surgery for Crohn's disease in childhood: influence of site of disease and operative procedure on outcome

Factors influencing outcome after surgery have been studied in 67 children requiring bowel resection or diversion of the faecal stream for Crohn's disease. Patients were divided into four groups on the basis of disease location at time of surgery, and mean follow-up was 4.5 years. All three children with panenteric disease (group 1) have relapsed. Best results were observed in cases with disease confined to the small bowel (group 2) and ileocaecal region (group 3), in whom surgery was followed by sustained remission in six out of seven and 24 out of 30 patients respectively. In the 27 children with colitis (group 4), results were mixed. Six of the seven patients who had staged colonic resections with a primary anastomosis relapsed, as did three out of four patients given a loop ileostomy to divert the faecal flow; in contrast, 15 out of 16 children who had a subtotal colectomy with ileostomy as the primary procedure have remained well, with only minor problems involving the rectal stump. An acceleration in growth velocity was observed during the first year after operation in 89 per cent of 40 children studied. Outcome after surgery for Crohn's disease in childhood depends mainly on disease location, but is influenced by the type of primary operation performed. In addition to symptomatic relief the principal early benefit of surgery is improved growth.

Disability insurance: merging group and individual policies

This case study explains how the Mecklenburg Medical group, after discovering a gap in the disability insurance for its physicians, followed through by negotiating a new plan which also covered non-physician employees.

Epidural versus general anaesthesia for elective caesarean section. Effect on Apgar score and acid-base status of the newborn

Elective Caesarean section deliveries over a 5-year period were studied to compare the effect of epidural block with general anaesthesia on the condition of the infant at birth. The Apgar score and umbilical arterial acid-base status were used as determinants of the latter. Epidural block was used in 139 (22.8%) mothers while 471 (77.2%) were performed under general anaesthesia. No babies in the epidural group were severely depressed (Apgar less than 4), compared with 6.2% in the general anaesthesia group. Only 4.3% of the epidural sections were moderately depressed (Apgar 4-6), compared with 15.4% of the others. These differences remained highly significant when infants of less than 2500 g were excluded, and when matched groups were compared. Mean umbilical arterial pH was similar within the two groups (pH 7.28), and was not consistent with asphyxia in almost 90% of the depressed infants. The findings suggest that general anaesthesia, rather than asphyxia or aortocaval compression, is responsible for most of the depressed infants born by elective Caesarean section. This may involve over 20% of babies delivered in this manner, so greater use of epidural block for elective Caesarean section is recommended. Further investigations are required to improve results with general anaesthesia.

Amoxycillin-clavulanic acid (Augmentin) antibiotic prophylaxis against wound infections in renal failure patients

A randomized, controlled trial of the use of amoxycillin with clavulanic acid (Augmentin) for prophylaxis against wound infections following major surgery, including transplantation, in patients with chronic renal failure, was undertaken. Six of 22 control patients developed wound infections (27%) whereas no patient in the treatment group (24) developed a wound infection (P less than 0.05). After the termination of this trial, the next 35 consecutive patients received prophylactic amoxycillin/clavulanate; of these only two developed wound infections associated with leakage from their pancreatic anastomoses. All the wound infections were shown to be caused by bacteria sensitive to amoxycillin/clavulanate. Pharmacokinetic studies in patients have shown that a bactericidal concentration of the drugs was present for up to 20 h post-operatively in patients on dialysis, and in recipients of non-functioning renal transplants. In patients with normal renal transplant function excretion of the drug within 12 h was observed.

Bulbocavernosus reflex latency in the investigation of diabetic impotence

Impotence in males is a well recognised complication of diabetes mellitus, commonly held to be due to an autonomic neuropathy. The aim of this study was to determine the incidence of periphero-conus neuropathy in diabetic impotence. Nineteen diabetic males seeking treatment for loss of potency had bulbocavernosus reflex latency (BCRL) and sacral reflex latencies (SRLs) performed. The conduction studies indicated that impotence in these cases was associated with peripheral neuropathy in 21% of patients and that BCRL and SRLs are sensitive and useful diagnostic tests.

Response of the normal human ankle joint to imposed sinusoidal movements

Ankle joints were subjected to sinusoidal movements at a range of amplitudes and frequencies. Records were made of electromyograms (e.m.g.s) in calf muscles, and of the forces at the joints. When the leg is relaxed, the ankle joint resists an imposed sinusoidal movement with a small approximately sinusoidal force. It is stiffer in its resistance to small movements than to large ones, and this resistance is greater when the joint is dorsiflexed than when it is plantarflexed. If the subject exerts a steady mean flexing force, the imposed sinusoidal movement generates reflex activity which may be recorded as a modulation of the gastrocnemius and soleus e.m.g.s. The e.m.g. response to the sinusoidal movement occurs later in cycles of movement at high than at low frequencies, as one could expect of a reflex pathway that involves a delay. The results suggest that this delay is between 50 and 60 ms, and we conclude that under these circumstances spinal stretch reflexes are playing the important part. The relation of the resisting force to the movement has been displayed as a vector. As the frequency changes, this vector describes the circular path that is characteristic of a system which includes delays or lags; this path enables one to draw conclusions about the amplitude and timing of the reflex resistance to the movement. When a subject exerts a moderate flexing force against the sinusoidal movement for some minutes, the reflex response becomes progressively potentiated. A subject whose reflex responses are normally slight may then exhibit a vigorous reflex response to the movement of that ankle. This enhancement of spinal reflex activity was accompanied by an increase in the myotatic reflex response at the ankle. Reflex responses to sinusoidal movement were most clearly seen when the subject exerted a mean flexing force that amounted to about one-fifth of his maximum. Very small movements (+/- 0.5 degrees) generated little or no reflex response. With large amplitudes of movement there was more reflex activity, but at some amplitude (which varied from subject to subject and from time to time) the reflex mechanism appeared to 'saturate', and further increases in amplitude were not accompanied by comparable increases in the reflex response. With movements at 10-15 Hz the e.m.g. response often became large in alternate cycles, with less activity in the intervening cycles.(ABSTRACT TRUNCATED AT 400 WORDS)