Investigation of Johne's disease in Tasmanian fallow deer (Dama dama).

In 2012 when many sheep flocks in northern-central Tasmania were experiencing a high prevalence of ovine Johne's disease, 34 wild adult fallow deer shot on or near infected properties were negative to microscopic Mptb lesions of the ileo-caecal valve, terminal ileum and ileo-caecal lymph nodes. This study demonstrated 95% confidence of detecting Johne's disease in this fallow deer population if ≥10% of animals were shedding Mycobacterium avium subsp. paratuberculosis in their faeces, or if ≥21% of animals were sub-clinically infected.

Is There a Relationship Between Body Mass Index and Fluoroscopy Time During Cervical Interlaminar Epidural Steroid Injections?

BACKGROUND: The challenge of obtaining medical imaging in individuals with higher body mass index (BMI) is described, but there is minimal data regarding the relationship between BMI and fluoroscopy time during cervical interlaminar epidural steroid injection (CIESI). OBJECTIVE: To determine the relationship between BMI and fluoroscopy time during CIESI. METHODS: Retrospective cohort study of patients who underwent fluoroscopically guided CIESI between January 2014 and February 2015 at an academic pain medicine center. Fluoroscopy time data were collected. Comparisons based on analysis of variance were made between patients with normal (<25.0 kg/m 2 ), overweight (25.0-29.9 kg/m 2 ), and obese (≥30.0 kg/m 2 ) BMI. RESULTS: Of 399 procedure encounters, 366 had documented BMI and fluoroscopy time data and were included for analysis. Mean age (± SD) in this cohort was 53 ± 13 years, including 189 females (52%) and 205 first-time injections. Mean fluoroscopy time for all injections was 18 ± 10 seconds. Separated by categorical BMI class, the mean fluoroscopy time was 18 ± 9 seconds for normal weight patients, 17 ± 10 seconds for overweight patients, and 20 ± 11 seconds for obese patients, respectively. Post hoc analysis showed that fluoroscopy time was significantly longer only in obese compared with overweight patients ( P = 0.02). Trainee involvement and first-time vs repeat injection did not significantly alter fluoroscopy time ( P = 0.17 and P = 0.12, respectively). CONCLUSIONS: The findings of this study indicate that BMI does not appear to have a clinically significant impact on fluoroscopy time during cervical interlaminar epidural steroid injection procedures. Future study is needed to directly quantify radiation exposure in patients and practitioners, as well as the associated health risk.

The Impact of Body Mass Index on Fluoroscopy Time During Lumbar Epidural Steroid Injection; A Multicenter Cohort Study.

Objective: This study aimed to assess the relationship between BMI and fluoroscopy time during lumbar epidural steroid injections (LESIs) performed for lumbosacral radicular pain. Design: Multicenter retrospective cohort study. Setting: Three academic, outpatient pain treatment centers. Subjects: Patients who underwent fluoroscopically guided LESI. Methods: Mean and standard deviation (SD) fluoroscopy time were compared between patients with normal (18.5-24.9 kg/m2), overweight (25.0-29.9 kg/m2), and obese (≥30.0 kg/m2) BMI. Statistical significance was set at P=0.01 due to multiple comparisons. Results: A total of 2,930 procedure encounters were included, consisting of 598 interlaminar LESIs and 2,332 transforaminal LESIs. Fluoroscopy time was significantly longer in the obese patients compared to normal and overweight patients during interlaminar LESI (P < 0.01). Fluoroscopy time was significantly longer with each increasing BMI category in during transforaminal LESI (P < 0.01). These relationships remained when a trainee was involved (P < 0.01; P<0.01), during repeat injections (P < 0.01; P < 0.01), and during bilateral transforaminal LESIs (P < 0.01). While longer fluoroscopy times were required in high BMI categories during L5-S1 transforaminal LESI (P < 0.01), there was no relationship between fluoroscopy time and BMI during L4-L5 and S1 transforaminal LESI (P = 0.02; P = 0.13). Fluoroscopy time during interlaminar LESI compared to transforaminal LESI was significantly lower within all BMI categories (all P<0.01). Conclusions: The findings of this study indicate that fluoroscopy time is increased during interlaminar LESIs and during L5-S1 transforaminal LESIs in patients who are obese. These relationships are not affected by injection number, performance of bilateral injections, or trainee involvement. Further study is needed to determine if this increase in fluoroscopy time is indicative of a clinically significant associated increase in radiation dose.

Surgical protocol involving the infusion of paramagnetic microparticles for preferential incorporation within porcine islets.

INTRODUCTION: Despite significant advances, widespread applicability of islet cell transplantation remains elusive. Refinement of current islet isolation protocols may improve transplant outcomes. Islet purification by magnetic separation has shown early promise. However, surgical protocols must be optimized to maximize the incorporation of paramagnetic microparticles (MP) within a greater number of islets. This study explores the impact of MP concentration and infusion method on optimizing MP incorporation within islets. METHODS: Five porcine pancreata were procured from donors after cardiac death. Splenic lobes were isolated and infused with varying concentrations of MP (8, 16, and 32 × 10(8) MP/L of cold preservation solution) and using one of two delivery techniques (hanging bag versus hand-syringe). After procurement and infusion, pancreata were stored at 0°C to 4°C during transportation (less than 1 hour), fixed in 10% buffered formalin, and examined by standard magnetic resonance imaging (MRI) and histopathology. RESULTS: T2*-weighted MRI showed homogeneous distribution of MP in all experimental splenic lobes. In addition, histologic analysis confirmed that MP were primarily located within the microvasculature of islets (82% to 85%), with few MP present in acinar tissue (15% to 18%), with an average of five to seven MP per islet (within a 5-µm thick section). The highest MP incorporation was achieved at a concentration of 16 × 10(8) MP/L using the hand-syringe technique. CONCLUSION: This preliminary study suggests that optimization of a surgical protocol, MP concentrations, and applied infusion pressures may enable more uniform distribution of MP in the porcine pancreas and better control of MP incorporation within islets. These results may have implications in maximizing the efficacy of islet purification by magnetic separation.

Molecular insights into uremic cardiomyopathy: cardiotonic steroids and Na/K ATPase signaling.

Patients with chronic renal failure develop a "uremic" cardiomyopathy characterized by diastolic dysfunction, left ventricular hypertrophy, fibrosis, and systemic oxidant stress. Patients with chronic renal failure also are known to have increases in the circulating concentrations of endogenous cardiotonic steroids (also referred to as endogenous digitalis-like substances.) Endogenous cardiotonic steroids produce reactive oxygen species as part of the signal cascade induced by binding to the plasmalemmal Na/K-ATPase in patients, and this signal cascade appears capable of inducing several key pathophysiologic features of uremic cardiomyopathy. In addition, these patients develop both fibrosis and oxidant stress without a known mechanism. In this review we highlight data supporting the hypothesis that endogenous cardiotonic steroids are a key molecular component involved in the diastolic dysfunction, left ventricular hypertrophy, fibrosis, and systemic oxidant stress associated with chronic kidney disease.

Hypokalemia potentiates ouabain's effect on calcium cycling and cardiac growth.

We have previously noted that in neonatal myocytes grown in culture, reductions in extracellular K+ concentration produced a hypertrophic response as assessed by induction of early response genes, atrial natriuretic peptide and skeletal actin and repression of the alpha 3 isoform of the sodium pump in a dose dependent manner. Similarly, decreases in media K+ concentration caused increases in cytosolic calcium concentration in a dose dependent manner, which correlated with repression of alpha 3 expression. In the current study we demonstrate that decreases in media K+ concentration caused increases in cytosolic calcium concentration in isolated adult rat cardiac myocytes. These increases are potentiated by the addition of the cardiotonic steroid, ouabain and blocked by the addition of the Src kinase inhibitor Herbimycin A. In parallel studies performed in vivo, when rats subjected to dietary K+ restriction were subsequently subjected to partial (5/6th) nephrectomy for 4 weeks, cardiac growth was greater than in rats fed a control diet. These data suggest that hypokalemia may produce phenotypic alterations consistent with cardiac hypertrophy as well as potentiate the cardiovascular effects of cardiotonic steroids.

Dual modes of 5-(N-ethyl-N-isopropyl)amiloride modulation of apical dipeptide uptake in the human small intestinal epithelial cell line Caco-2.

Selective pharmacological Na+/H+ exchange (NHE) inhibitors were used to identify functional NHE isoforms in human small intestinal enterocytes (Caco-2) and to distinguish between direct and indirect effects on transport via the intestinal di/tripeptide transporter hPepT1. The relative potencies of these inhibitors to inhibit 22Na+ influx identifies NHE3 and NHE1 as the apical and basolateral NHE isoforms. The Na+-dependent (NHE3-sensitive) component of apical dipeptide ([14C] Gly-Sar) uptake was inhibited by the selective NHE inhibitors with the same order of potency observed for inhibition of apical 22Na+ uptake. However, 5-(N-ethyl-N-isopropyl) amiloride (EIPA) also reduced [14C]Gly-Sar uptake in the absence of Na+ and this inhibition was concentration and pH (maximal at pH 5.5) dependent. NHE3 inhibition by S1611 and S3226 modulates dipeptide uptake indirectly by reducing the transapical driving force (H+ electrochemical gradient). EIPA (at 100 microM) has similar effects, but at higher concentrations (> 200 microM) also has direct inhibitory effects on hPepT1.

Optimal absorptive transport of the dipeptide glycylsarcosine is dependent on functional Na+/H+ exchange activity.

Optimal nutrient absorption across the intestinal epithelium is dependent on the co-ordinated activity of a number of membrane transporters. Di/tripeptide transport across the luminal membrane of the intestinal enterocyte is mediated by the H(+)-coupled di/tripeptide transporter hPepT1. hPepT1 function is dependent on the existence of a pH gradient (maintained, in part, by the action of the Na(+)/H(+) exchanger NHE3) across the apical membrane of the small intestinal epithelium. The physiological problem addressed here was to determine how two transporters (hPepT1 and NHE3), involved in nutrient absorption and pH(i) homeostasis, function co-operatively to maximise dipeptide absorption when both operate sub-optimally at typical mucosal surface pH values (pH 6.1-6.8). Functional hPepT1 activity in human intestinal epithelial (Caco-2) cell monolayers was determined by measurement of apical uptake and apical-to-basolateral transport of the dipeptide glycylsarcosine. The dependence of hPepT1 on NHE3 activity was measured (either after Na(+) removal or addition of the NHE3-selective inhibitor S1611) using both Caco-2 cell monolayers and hPepT1-expressing Xenopus laevis oocytes. Apical glycylsarcosine uptake in Caco-2 cell monolayers was modulated by apical pH, extracellular Na(+), incubation time and S1611. Uptake in hPepT1-expressing oocytes was independent of Na(+) or S1611. We conclude that functional NHE3 activity is required to allow optimal absorption of dipeptides across the human intestinal epithelium.

Control of Mycobacterium avium subsp. paratuberculosis infection in agricultural species.

Paratuberculosis or Johne's disease is a chronic intestinal disease caused by Mycobacterium avium subsp. paratuberculosis, which continues to spread in agricultural species. Control of paratuberculosis is challenging and should not be underestimated. Due to the long incubation period of the infection, disease is largely subclinical in domesticated livestock. Hence, direct effects on animal productivity and welfare are often masked and may appear insufficient to justify large investments in control programmes by individual farmers, livestock industries or governments. Furthermore, in some countries the main effects of the disease are indirect, resulting from the impact of market discrimination against herds and flocks known to be infected, or from the control measures enforced to reduce transmission. In such circumstances, producers may be unwilling to co-operate with surveillance that may detect infection in herds or flocks. As control programmes are rarely successful in eliminating the infection from a herd or flock in the short term without an aggressive and costly programme, financial and community support assists producers to deal with the challenge. Successful prevention and control depends on animal health authorities and livestock industries acquiring a good understanding of the nature and epidemiology of infection, and of the application of tools for diagnosis and control. Building support for control programmes under the leadership of the affected livestock industries is critical, as programmes are unlikely to be successful without ongoing political will, supported by funding for research, surveillance and control.

Do pulmonary artery catheters cause or increase tricuspid or pulmonic valvular regurgitation?

UNLABELLED: There are few quantitative data on the extent or mechanism of pulmonary artery catheter (PAC)-induced valvular dysfunction. We hypothesized that PACs cause or worsen tricuspid and pulmonic valvular regurgitation, and tested this hypothesis by using transesophageal echocardiography. In 54 anesthetized adult patients, we measured color Doppler jet areas of tricuspid regurgitation (TR) in two planes (midesophageal [ME] 4-chamber and right ventricular inflow-outflow views) and pulmonic insufficiency (PI) in one plane (ME aortic valve long-axis view), both before and after we advanced a PAC into the pulmonary artery. Regurgitant jet areas and hemodynamic measurements were compared by using paired t-test. There were no significant changes in blood pressure or heart rate after passage of the PAC. After PAC placement, the mean PI jet area was not significantly increased. The mean TR jet area increased significantly in the right ventricular inflow-outflow view (+0.37 +/- 0.11 cm(2)) (P = 0.0014), but did not increase at the ME 4-chamber view. Seventeen percent of patients had an increase in TR jet area > or =1 cm(2); 8% of patients had an increase in PI jet area >/=1 cm(2). IMPLICATIONS: In patients without pulmonic or tricuspid valvular pathology, placement of a pulmonary artery catheter (PAC) worsened tricuspid regurgitation, which is consistently visualized in the right ventricular inflow-outflow view, and often not seen in the midesophageal 4-chamber view. This is consistent with malcoaptation of the anterior and posterior leaflets. PAC-induced pulmonic insufficiency was rarely detected in the midesophageal aortic valve long-axis view. We conclude that a PAC is very unlikely to be the sole cause of severe tricuspid regurgitation or pulmonic insufficiency.

A double ring closing metathesis reaction in the rapid, enantioselective synthesis of NK-1 receptor antagonists.

[structure: see text]. The NK-1 receptor antagonist 1 has been prepared in seven steps from phenylglycine methyl ester. The key steps are a double ring closing metathesis reaction of tetraene 7 to prepare spirocycle 6 and a reductive Heck reaction to introduce the aryl moiety. This latter reaction discriminates the olefins of compound 6 and proceeds in a highly regio- and stereoselective manner.

Progress in national control and assurance programs for ovine Johne's disease in Australia.

Since the detection of ovine Johne's disease in Australia in 1980, 578 flocks have been diagnosed as infected, with 442 of these still infected. The disease was initially believed to be confined to the central tablelands area of NSW, but has subsequently been shown to be more widely distributed. Sheep strains of M. paratuberculosis are known to infect sheep and goats in south-eastern Australia. Although sheep strains have recently been identified in some cattle in Australia, epidemiological evidence to date supports the distinction between ovine Johne's disease, caused by sheep strains in sheep and goats, and bovine Johne's disease, caused by cattle strains in cattle, goats and alpaca, as a basis for control and eradication strategies. Four national initiatives to control and better understand OJD are outlined. The Australian Johne's Disease Market Assurance Program for sheep was launched in May 1997. By December 1998, 548 flocks had achieved an assessed negative status. Three flocks assigned a flock status have subsequently been found to be infected. National standards for State control of Johne's disease through zoning, movement controls and procedures in infected and suspect flocks have also been developed. In addition, a $40.1 m National Ovine Johne's Disease Control and Evaluation Program was agreed to in August 1998, and is currently being implemented. It is jointly funded by National and State industries, and Commonwealth and State governments. Its objectives are to deliver, through research and surveillance, a solid basis for a future decision on the most appropriate course for dealing with OJD and to maintain control of OJD nationally.

Progress in national control and assurance programs for bovine Johne's disease in Australia.

Cattle strains of Mycobacterium paratuberculosis are known to infect cattle, goats and alpaca in southeastern Australia, where there are also significant numbers of farmed deer. Although sheep strains have recently been identified in some cattle in Australia, epidemiological evidence to date supports the distinction (between bovine Johne's disease (JD), caused by cattle strains in cattle, goats and alpaca, and ovine JD, caused by sheep strains in sheep and goats) for the purposes of control and assurance programs. The National Johne's Disease Control Program is coordinated by the Australian Animal Health Council, working with the livestock industries and with the Commonwealth, state and territory governments. The council also brokers industry and government funding for the program. The National Johne's Disease Market Assurance Program for Cattle was launched in 1996 as the first of a suite of voluntary national market assurance programs (MAPs) to assess and certify herds as negative for JD. By December 1998, over 550 herds had achieved an assessed negative status. A MAP was also launched for alpaca in 1998 and a program for goats should be finalized in early 1999. National standards for state control of JD through zoning, movement controls and procedures in infected and suspect herds have also been developed. The paper covers factors affecting development and implementation, uptake of and improvements to national control and assurance programs for bovine JD in Australia.

A practical and efficient preparation of the releasable naphthosultam side chain of a novel anti-MRSA carbapenem.

A practical large-scale synthesis of the naphthosultam-based side chain of the anti-MRSA antibiotic 1 has been achieved in 29% overall yield over seven steps from 1-methylnaphthalene. The synthesis was completed without the use of protecting groups, featuring a novel naphthosultam annelation, a chemoselective acid-catalyzed triflation, and the use of a novel naphthosultam dianion to effect functionalization through benzylic metalation.

Renal artery angioplasty and stent placement: predictors of a favorable outcome.

BACKGROUND: Renal artery stenosis is a common disorder and is an established cause of hypertension and renal insufficiency. Although treatment with renal artery stents has been shown to improve blood pressure and renal function for some patients, the patient population most likely to benefit is unknown. The current study was designed to determine which factors are predictive of improved blood pressure and renal function when patients with renal artery stenosis are treated with renal artery angioplasty and stent placement. METHODS: In a prospective evaluation 127 consecutively enrolled patients with renal artery stenosis in 171 vessels were treated with angioplasty and intravascular stents. Blood pressure and serum creatinine concentration were measured before stent placement and during the follow-up period. RESULTS: The mean length of the follow-up period was 15 +/- 14 months. Mean systolic blood pressure improved among patients with hypertension (from 177 +/- 26 mm Hg before stent placement to 151 +/- 24 mm Hg 6 months after stent placement (P <.001). The greatest improvement occurred among those with the highest baseline systolic blood pressure. This beneficial effect on blood pressure was sustained for 3 years. Sex, age, diastolic blood pressure, number of vessels into which stents were placed, serum creatinine concentration, presence of bilateral disease, race, and severity of stenosis were not predictive of improved blood pressure. Mean creatinine concentration was not significantly changed for the group as a whole. A significant decrease in serum creatinine concentration occurred among 43% of patients with baseline renal insufficiency. None of the examined variables was predictive of improvement. CONCLUSIONS: Renal artery angioplasty and stent placement produced a significantly greater reduction in systolic blood pressure among patients with the highest baseline systolic blood pressure. Other examined variables were not predictive of a significant improvement in blood pressure. No examined variable was predictive of improved renal function. We concluded that management of renal artery stenosis with renal artery angioplasty and stent placement is most likely to result in significant improvement in systolic blood pressure among patients with the highest baseline systolic blood pressure.

The impact of intraoperative culture on treatment and outcome in children with perforated appendicitis.

BACKGROUND: Most protocols for the operative treatment of perforated appendicitis use a routine culture. Although isolated studies suggest that routine culture may not be necessary, these recommendations generally are not based on objective outcome data. METHODS: The authors reviewed the records of 308 children who underwent operative treatment for perforated appendicitis between 1988 and 1998 to determine if information gained from routine culture changes the management or improves outcome. Inclusion criteria included either gross or microscopic evidence of appendiceal perforation. RESULTS: Mean patient age was 7.5 years, 51% were boys, and there was no mortality. The majority of children (96%) underwent culture that was positive for either aerobes (21%), anaerobes (19%), or both (57%). Antibiotics were changed in only 16% of the patients in response to culture results. The use of empiric antibiotics, as compared with modified antibiotics, was associated with a lower incidence of infectious complication, shorter fever duration, and decreased length of hospitalization. We also investigated the relationship between culture isolates and antibiotic regimens with regard to outcome. The utilization of antibiotics suitable for the respective culture isolate or organism sensitivity was associated with an increased incidence of infectious complication and longer duration of both fever and length of hospitalization. Finally, the initial culture correlated poorly with subsequent intraabdominal culture (positive predictive value, 11%). CONCLUSION: These outcome data strongly suggest that the practice of obtaining routine cultures can be abandoned, and empiric broad spectrum antibiotic coverage directed at likely organisms is completely adequate for treatment of perforated appendicitis in children.

Modulation of immunologic responses to HIV-1MN recombinant gp160 vaccine by dose and schedule of administration. National Institute of Allergy and Infectious Diseases AIDS Vaccine Evaluation Group.

The safety and immunogenicity of HIV-1MN recombinant gp160 (MN rgp160) vaccine in healthy, uninfected volunteers was tested in a double-blind study with a factorial design. By random assignment, 20 volunteers received three 200 micrograms doses of MN rgp160 and four volunteers received placebo at days 0, 28, and 168 or 0, 56, and 224. Of the 24 volunteers, 16 received 200 micrograms or 800 micrograms of MN rgp160 and two received placebo at day 532 (month 18). The vaccine was safe. It induced T cell memory measured by Th1 cytokine production and lymphocyte proliferation, and serum anti-MN rgp160 IgG (all subclasses) and IgA antibodies. Fifteen of 20 vaccinees developed neutralizing antibody. The regimen including immunizations on days 0, 28, and 168 followed by the 800 micrograms fourth dose was most immunogenic.

Renal dose dopamine does not alter the response to beta-adrenergic stimulation by isoproterenol in healthy human volunteers.

OBJECTIVES: To determine if renal dose dopamine (3 microg/kg/min) alters the heart rate (HR) by itself, or if a dopamine infusion alters the HR response to bolus doses of the beta-adrenergic agonist isoproterenol in healthy human subjects. DESIGN: Prospective study. SETTING: Clinical laboratory of a university-affiliated academic medical center. SUBJECTS: A total of 15 healthy nonpregnant women and men aged 21 to 44 years. INTERVENTIONS: Subjects were monitored continuously with bedside ECG, pulse oximetry, and ambulatory ECG recording to measure the maximal HR response to separate injections of 10, 20, and 30 ng/kg of isoproterenol, given before, during, and after the infusion of 3 microg/kg/min of dopamine. MEASUREMENTS AND MAIN RESULTS: Dopamine in the absence of isoproterenol did not alter baseline HR significantly (62.7+/-2.2 beats/min without dopamine; 65.4+/-2.2 with dopamine; p=0.15). All three doses of isoproterenol increased HR significantly above baseline, both in the presence and absence of dopamine (p<0.001). Dopamine infusion resulted in a higher HR following isoproterenol only for the 20-ng/kg dose. The incremental increases in HR, defined as the difference between peak HR following isoproterenol and baseline HR, were not increased during dopamine infusion for any of the doses of isoproterenol. Nausea was reported by 5 of the 15 subjects during the dopamine infusion. CONCLUSIONS: In healthy human subjects, infusion of 3 microg/kg/min of dopamine does not significantly increase the HR when combined with beta-adrenergic stimulation using isoproterenol, suggesting neither an additive nor antagonistic interaction between the two drugs. While our study did not demonstrate an increase in HR in healthy subjects, the risk of increasing the chronotropic response to beta-adrenergic inotropic medications with "renal dose" dopamine in critically ill patients needs to be investigated. The frequency of nausea during dopamine infusion also may influence consideration of using dopamine to augment splanchnic blood flow and renal function in conscious patients.