SOD1-Related Cerebellar Ataxia and Motor Neuron Disease: Cp Variant as Functional Modifier?

We describe a novel superoxide dismutase (SOD1) mutation-associated clinical phenotype of cerebellar ataxia and motor neuron disease with a variant in the ceruloplasmin (Cp) gene, which may have possibly contributed to a multi-factorial phenotype, supported by genetic and protein structure analyses.

Geographic distribution and predictors of diagnostic delays among possible TB patients in Uganda

BACKGROUND

Understanding the geographic distribution and factors associated with delayed TB diagnosis may help target interventions to reduce delays and improve patient outcomes.

METHODS

We conducted a secondary analysis of adults undergoing TB evaluation within a public health demonstration project in Uganda. Using Global Moran's I (GMI) and Getis-Ord GI* statistics, we evaluated for residential clustering and hotspots associated with patient-related and health system-related delays. We performed multivariate logistic regression to identify individual predictors of both types of delays.

RESULTS

Of 996 adults undergoing TB evaluation (median age: 37 years, IQR 28-49), 333 (33%) experienced patient delays, and 568 (57%) experienced health system delays. Participants were clustered (GMI 0.47-0.64, P ⩽ 0.001) at the sub-county level, but there were no statistically significant hotspots for patient or health system delays. Married individuals were less likely to experience patient delays (OR 0.6, 95% CI 0.48-0.75; P < 0.001). Those aged 38-57 years (OR 1.2, 95% CI 1.07-1.38; P = 0.002) were more likely than those aged ⩾58 years to experience patient delays. Knowledge about TB (OR 0.8, 95% CI 0.63-0.98; P = 0.03) protected against health system delays.

CONCLUSIONS

We did not identify geographic hotspots for TB diagnostic delays. Instead, delays were associated with individual factors such as age, marital status and TB knowledge.

Assessing a norming intervention to promote acceptance of HIV testing and reduce stigma during household tuberculosis contact investigation: protocol for a cluster-randomised trial

INTRODUCTION

HIV status awareness is important for household contacts of patients with tuberculosis (TB). Home HIV testing during TB contact investigation increases HIV status awareness. Social interactions during home visits may influence perceived stigma and uptake of HIV testing. We designed an intervention to normalise and facilitate uptake of home HIV testing with five components: guided selection of first tester; prosocial invitation scripts; opt-out framing; optional sharing of decisions to test; and masking of decisions not to test.

METHODS AND ANALYSIS

We will evaluate the intervention effect in a household-randomised controlled trial. The primary aim is to assess whether contacts offered HIV testing using the norming strategy will accept HIV testing more often than those offered testing using standard strategies. Approximately 198 households will be enrolled through three public health facilities in Kampala, Uganda. Households will be randomised to receive the norming or standard strategy and visited by a community health worker (CHW) assigned to that strategy. Eligible contacts ≥15 years will be offered optional, free, home HIV testing. The primary outcome, proportion of contacts accepting HIV testing, will be assessed by CHWs and analysed using an intention-to-treat approach. Secondary outcomes will be changes in perceived HIV stigma, changes in perceived TB stigma, effects of perceived HIV stigma on HIV test uptake, effects of perceived TB stigma on HIV test uptake and proportions of first-invited contacts who accept HIV testing. Results will inform new, scalable strategies for delivering HIV testing.

ETHICS AND DISSEMINATION

This study was approved by the Yale Human Investigation Committee (2000024852), Makerere University School of Public Health Institutional Review Board (661) and Uganda National Council on Science and Technology (HS2567). All participants, including patients and their household contacts, will provide verbal informed consent. Results will be submitted to a peer-reviewed journal and disseminated to national stakeholders, including policy-makers and representatives of affected communities.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT05124665.

Quality of care in childhood tuberculosis diagnosis at primary care clinics in Kampala, Uganda

OBJECTIVE

To assess the quality of routine childhood tuberculosis (TB) evaluation in Kampala, Uganda.

SETTING AND DESIGN

This was a cross-sectional study of children aged <15 years attending six government-run clinics from November 2015 to December 2016. Clinicians completed a standardized patient record form for all child visits. We assessed the following performance indicators of TB evaluation developed based on the Desk Guide of the International Union Against Tuberculosis and Lung Disease, an evidence-based decision aid on childhood TB diagnosis and management for clinicians: proportion screened for TB symptoms or contact history, proportion referred for laboratory evaluation if screen-positive, and proportion treated for TB if test-positive or meeting clinical criteria.

RESULTS

Of 24 566 consecutive children enrolled, 11 614 (47%) were fully screened for TB symptoms. Of 1747 (15%) children who screened positive, 360 (21%) had sputum examined, including 159 (44%) using smear microscopy, 244 (67%) using Xpert® MTB/RIF, and 52 (14%) using both techniques. Treatment was initiated in 18/20 (80%) children who tested positive. An additional 65 screen-positive children met the clinical criteria for TB; none were initiated on treatment.

CONCLUSIONS

Large gaps exist along the pathway to diagnosis and treatment of childhood TB. There is an urgent need for enhanced implementation of evidence-based approaches to TB diagnosis to improve outcomes in childhood TB.

'Something so hard': a mixed-methods study of home sputum collection for tuberculosis contact investigation in Uganda

BACKGROUND

Home sputum collection could facilitate prompt evaluation and diagnosis of tuberculosis (TB) among contacts of patients with active TB. We analyzed barriers to home-based collection as part of an enhanced intervention for household TB contact investigation in Kampala, Uganda.

DESIGN

We conducted a convergent mixed-methods study to describe the outcomes of home sputum collection in 91 contacts and examine their context through 19 nested contact interviews and two focus group discussions with lay health workers (LHWs).

RESULTS

LHWs collected sputum from 35 (39%) contacts. Contacts reporting cough were more likely to provide sputum than those with other symptoms or risk factors (53% vs. 15%, RR 3.6, 95%CI 1.5-2.8, P < 0.001). Males were more likely than females to provide sputum (54% vs. 32%, RR 1.7, 95%CI 1.0-2.8, P = 0.05). Contacts said support from the index patient and the convenience of the home visit facilitated collection. Missing containers and difficulty producing sputum spontaneously impeded collection. Women identified stigma as a barrier. LHWs emphasized difficulty in procuring sputum and discomfort pressing contacts to produce sputum.

CONCLUSIONS

Home sputum collection by LHWs entails different challenges from sputum collection in clinical settings. More research is needed to develop interventions to mitigate stigma and increase success of home-based collection.

Patterns of usage and preferences of users for tuberculosis-related text messages and voice calls in Uganda

BACKGROUND

Little information exists about mobile phone usage or preferences for tuberculosis (TB) related health communications in Uganda.

METHODS

We surveyed household contacts of TB patients in urban Kampala, Uganda, and clinic patients in rural central Uganda. Questions addressed mobile phone access, usage, and preferences for TB-related communications. We collected qualitative data about messaging preferences.

RESULTS

We enrolled 145 contacts and 203 clinic attendees. Most contacts (58%) and clinic attendees (75%) owned a mobile phone, while 42% of contacts and 10% of clinic attendees shared one; 94% of contacts and clinic attendees knew how to receive a short messaging service (SMS) message, but only 59% of contacts aged 45 years (vs. 96% of contacts aged <45 years, P = 0.0001) did so. All contacts and 99% of clinic attendees were willing and capable of receiving personal-health communications by SMS. Among contacts, 55% preferred detailed messages disclosing test results, while 45% preferred simple messages requesting a clinic visit to disclose results.

CONCLUSIONS

Most urban household TB contacts and rural clinic attendees reported having access to a mobile phone and willingness to receive TB-related personal-health communications by voice call or SMS. However, frequent phone sharing and variable messaging abilities and preferences suggest a need to tailor the design and monitoring of mHealth interventions to target recipients.

Pharmacokinetics and safety of repeated oral dosing of acetaminophen in adult horses

BACKGROUND

There are no published studies on the pharmacokinetics of acetaminophen at the dosage used clinically (20 mg/kg), nor has the safety of multiple doses in horses been investigated.

OBJECTIVE

Define the pharmacokinetic parameters of oral acetaminophen at 20 mg/kg in adult horses as a single dose, and twice daily for 14 days to assess the safety of multiple dosing.

STUDY DESIGN

Pharmacokinetic study, multiple dose safety study.

METHODS

Eight healthy Thoroughbred geldings were given acetaminophen (20 mg/kg; 500 mg tablets) orally as a single dose followed by doses every 12 h for 14 days. Serial blood samples were collected for determination of plasma acetaminophen concentrations using high performance liquid chromatography with ultraviolet detection. Serum biochemical analysis, gastroscopy and liver biopsy were examined during the safety study.

RESULTS

Following a single dose, mean maximum concentration (C_max ) was 16.61 μg/mL at 1.35 h (T_max ), and drug concentration was below the lower limit of detection in most horses by 24 h. Elimination half-life (T_1/2 ) was 2.78 h. No significant accumulation was noted following multiple doses. Average C_max of acetaminophen following multiple oral dosing was 15.85 μg/mL, with a T_max of 0.99 h and T_1/2 of 4 h. Serum activities of sorbitol dehydrogenase were significantly decreased and total bilirubin concentrations were significantly increased following the last dose. No statistically significant changes were noted in gastroscopy scores.

MAIN LIMITATIONS

Only one dose level (20 mg/kg) was studied, sample size was small and only a single breed and sex was used, with no pretreatment liver biopsies.

CONCLUSION

This study described the pharmacokinetics of acetaminophen following single and multiple 20 mg/kg oral doses in adult horses and demonstrated the safety of acetaminophen with multiple oral dosing over 14 days. The summary is available in Portuguese - see Supporting information.

Oral reserpine administration in horses results in low plasma concentrations that alter platelet biology

BACKGROUND

Reserpine is a popular drug in the equine industry for long-term tranquilisation. Clinical observations revealed that blood from horses receiving oral reserpine was hypercoagulable. No studies have documented the pharmacokinetics of orally administered reserpine nor the effects of reserpine on platelets in horses.

OBJECTIVES

To evaluate the pharmacokinetics of oral reserpine in horses and the effects of clinically relevant concentrations of reserpine on platelet functionality in vitro.

STUDY DESIGN

Experimental controlled study.

METHODS

The pharmacokinetics of oral reserpine (2.5 mg/horse, once) were determined in six healthy adult horses. Plasma samples were collected and concentrations of reserpine were determined by UPLC-MS/MS. Using this data, the in vitro effects of reserpine on platelets were examined. Aggregation, adhesion and releasate assays for serotonin and thromboxane B₂ were performed on platelets exposed to varying concentrations of reserpine (0.01-10 ng/mL), aspirin (negative control) and saline (unexposed control).

RESULTS

Oral reserpine administration demonstrated low plasma concentrations with a C_max of 0.2 ± 0.06 ng/mL and a prolonged half-life of 23.6 ± 6.24 h. Simulations over a dose range of 2-8 μg/kg predicted C_max at steady state between 0.06-0.9 ng/mL. Platelets exposed to these reserpine concentrations in vitro displayed increased aggregation and adhesion compared to unexposed or aspirin-exposed platelets as well as compared to higher concentrations of reserpine. These functional changes correlated with lower concentrations of serotonin and higher concentrations of thromboxane B₂ in the platelet suspension supernatant.

MAIN LIMITATIONS

This study used a small number of horses and only in vitro platelet experiments.

CONCLUSIONS

Oral reserpine demonstrates low plasma concentrations and a prolonged half-life in horses. At these concentrations, reserpine causes significant changes in platelet function, most likely due to serotonin release and re-uptake which primes platelets for activation and thromboxane B₂ release. These findings suggest that clinicians should harvest blood for biological processing prior to the onset of reserpine administration.

Social determinants of tuberculosis evaluation among household contacts: a secondary analysis

Setting: Seven public sector tuberculosis (TB) units and surrounding communities in Kampala, Uganda. Objective: To evaluate the influence of household-level socio-economic characteristics on completion of TB evaluation during household contact investigation. Design: A cross-sectional study nested within the control arm of a randomized, controlled trial evaluating home-based sputum collection and short messaging service communications. We used generalized estimating equations to estimate the association between completion of TB evaluation and socio-economic determinants. Results: Of 116 household contacts referred to clinics for TB evaluation, 32 (28%) completed evaluation. Completing evaluation was strongly clustered by household. Controlling for individual symptoms, contacts from households earning below-median income (adjusted risk ratio [aRR] 0.28, 95%CI 0.09-0.88, P = 0.029) and contacts from households in which the head of household had no more than primary-level education (aRR 0.40, 95%CI 0.18-0.89, P = 0.025) were significantly less likely to complete evaluation for TB. Conclusion: Socio-economic factors such as low income and education increase the risk that household contacts of TB patients will experience barriers to completing TB evaluation themselves. Further research is needed to identify specific mechanisms by which these underlying social determinants modify the capability and motivation of contacts to complete contact investigation.

Multicentre, blinded, randomised clinical trial comparing the use of flunixin meglumine with firocoxib in horses with small intestinal strangulating obstruction

BACKGROUND

Small intestinal strangulating obstruction (SISO) is associated with endotoxaemia which leads to an increased risk of death. Nonsteroidal anti-inflammatory drugs (NSAIDs) are used to treat signs of endotoxaemia by inhibiting cyclo-oxygenases (COX). COX-1 is expressed constitutively and promotes gut barrier function, whereas COX-2 is inducible and contributes to the signs of endotoxaemia. In preclinical SISO trials, intestinal barrier recovery was more complete with reductions in endotoxin permeability in horses treated with COX-2 selective NSAIDs as compared with horses treated with flunixin meglumine.

OBJECTIVES

We hypothesised that treatment of post-surgical SISO horses with firocoxib (COX-2 selective) would reduce the signs of endotoxaemia to a greater extent than flunixin meglumine (nonselective COX inhibitor) while continuing to provide similar levels of pain control.

STUDY DESIGN

Blinded randomised clinical trial.

METHODS

In addition to clinical monitoring, preoperative and 12-, 24- and 48-h post-operative plasma samples were assessed for prostaglandin E₂ (PGE₂ ), thromboxane B₂ (TXB₂ ), TNF⍺ and soluble CD14 (sCD14).

RESULTS

In 56 recruited SISO horses, either flunixin meglumine (1.1 mg/kg, i.v., q12h) or firocoxib (0.3 mg/kg, i.v. loading dose; 0.1 mg/kg, i.v., q24h) was given in the post-operative period in three university hospitals from 2015 to 2017. COX-2 selectivity was confirmed by a relative lack of inhibition of the COX-1 prostanoid TXB₂ by firocoxib and significant inhibition by flunixin meglumine (P = 0.014). Both drugs inhibited the COX-2 prostanoid PGE₂ . There were no significant differences in pain scores between groups (P = 0.2). However, there was a 3.23-fold increased risk (P = 0.04) of increased plasma sCD14 in horses treated with flunixin meglumine, a validated biomarker of equine endotoxaemia.

MAIN LIMITATIONS

Horses were all treated with flunixin meglumine prior to referral. In addition, many horses were treated with lidocaine, which has been shown to mitigate the deleterious effects of flunixin meglumine.

CONCLUSIONS

In SISO cases, firocoxib reduced a biomarker of endotoxaemia as compared with flunixin meglumine while continuing to provide similar levels of pain control.

Integrating home HIV counselling and testing into household TB contact investigation: a mixed-methods study

Setting: Community health workers (CHWs) increasingly deliver community-based human immunodeficiency virus (HIV) counselling and testing (HCT) services. Less is known about how this strategy performs when integrated with household tuberculosis (TB) contact investigations. Objective: We conducted a prospective mixed-methods study to evaluate the feasibility and quality of CHW-facilitated, home-based HCT among household TB contacts. Design: CHWs visited households of consenting TB patients to screen household contacts for TB and HIV. They performed HIV testing using a serial enzyme-linked immunosorbent assay rapid-antibody testing algorithm. Laboratory technicians at health facilities re-tested the samples and coordinated quarterly HIV panel testing for CHWs. We conducted focus group discussions (FGDs) with CHWs on their experiences in carrying out home-based HCT. Results: Of 114 household contacts who consented to and underwent HIV testing by CHWs, 5 (4%) tested positive, 108 (95%) tested negative, and 1 (1%) had indeterminate results; 110 (96%) samples had adequate volume for re-testing. Overall agreement between CHWs and laboratory technicians was 99.1% (κ = 0.90, 95%CI 0.71-1.00, P < 0.0001). In FGDs, CHWs described context-specific social challenges to performing HCT in a household setting, but said that their confidence grew with experience. Conclusion: Home-based HCT by CHWs was feasible among household TB contacts and produced high-quality results. Strategies to address social challenges are required to optimize yield.

Feasibility of a streamlined tuberculosis diagnosis and treatment initiation strategy

OBJECTIVE:

To assess the feasibility of a streamlined strategy for improving tuberculosis (TB) diagnostic evaluation and treatment initiation among patients with presumed TB.

DESIGN:

Single-arm interventional pilot study at five primary care health centers of a streamlined, SIngle-saMPLE (SIMPLE) TB diagnostic evaluation strategy: 1) examination of two smear results from a single spot sputum specimen using light-emitting diode fluorescence microscopy, and 2) daily transportation of smear-negative sputum samples to Xpert® MTB/RIF testing sites.

RESULTS:

Of 1212 adults who underwent sputum testing for TB, 99.6% had two smears examined from the spot sputum specimen. Sputum was transported for Xpert testing within 1 clinic day for 83% (907/1091) of the smear-negative patients. Of 157 (13%) patients with bacteriologically positive TB, 116 (74%) were identified using sputum smear microscopy and 41 (26%) using Xpert testing of smear-negative samples. Anti-tuberculosis treatment was initiated in 142 (90%) patients with bacteriologically positive TB, with a median time to treatment of 1 day for smear-positive patients and 6 days for smear-negative, Xpert-positive patients.

CONCLUSION:

The SIMPLE TB strategy led to successful incorporation of Xpert testing and rapid treatment initiation in the majority of patients with bacteriologically confirmed TB in a resource-limited setting.

Higher cost of implementing Xpert(®) MTB/RIF in Ugandan peripheral settings: implications for cost-effectiveness

SETTING

Initial cost-effectiveness evaluations of Xpert(®) MTB/RIF for tuberculosis (TB) diagnosis have not fully accounted for the realities of implementation in peripheral settings.

OBJECTIVE

To evaluate costs and diagnostic outcomes of Xpert testing implemented at various health care levels in Uganda.

DESIGN

We collected empirical cost data from five health centers utilizing Xpert for TB diagnosis, using an ingredients approach. We reviewed laboratory and patient records to assess outcomes at these sites and10 sites without Xpert. We also estimated incremental cost-effectiveness of Xpert testing; our primary outcome was the incremental cost of Xpert testing per newly detected TB case.

RESULTS

The mean unit cost of an Xpert test was US$21 based on a mean monthly volume of 54 tests per site, although unit cost varied widely (US$16-58) and was primarily determined by testing volume. Total diagnostic costs were 2.4-fold higher in Xpert clinics than in non-Xpert clinics; however, Xpert only increased diagnoses by 12%. The diagnostic costs of Xpert averaged US$119 per newly detected TB case, but were as high as US$885 at the center with the lowest volume of tests.

CONCLUSION

Xpert testing can detect TB cases at reasonable cost, but may double diagnostic budgets for relatively small gains, with cost-effectiveness deteriorating with lower testing volumes.

Insights into Pathophysiology from Medication-induced Tremor

Background

Medication-induced tremor (MIT) is common in clinical practice and there are many medications/drugs that can cause or exacerbate tremors. MIT typically occurs by enhancement of physiological tremor (EPT), but not all drugs cause tremor in this way. In this manuscript, we review how some common examples of MIT have informed us about the pathophysiology of tremor.

Methods

We performed a PubMed literature search for published articles dealing with MIT and attempted to identify articles that especially dealt with the medication's mechanism of inducing tremor.

Results

There is a paucity of literature that deals with the mechanisms of MIT, with most manuscripts only describing the frequency and clinical settings where MIT is observed. That being said, MIT emanates from multiple mechanisms depending on the drug and it often takes an individualized approach to manage MIT in a given patient.

Discussion

MIT has provided some insight into the mechanisms of tremors we see in clinical practice. The exact mechanism of MIT is unknown for most medications that cause tremor, but it is assumed that in most cases physiological tremor is influenced by these medications. Some medications (epinephrine) that cause EPT likely lead to tremor by peripheral mechanisms in the muscle (β-adrenergic agonists), but others may influence the central component (amitriptyline). Other drugs can cause tremor, presumably by blockade of dopamine receptors in the basal ganglia (dopamine-blocking agents), by secondary effects such as causing hyperthyroidism (amiodarone), or by other mechanisms. We will attempt to discuss what is known and unknown about the pathophysiology of the most common MITs.

The sixth vital sign: HIV status assessment and severe illness triage in Uganda

Setting: Four in-patient health facilities in western Uganda. Objective: To determine the impact of an innovative multi-modal quality improvement program on human immunodeficiency virus (HIV) status assessment and the impact of HIV status on severe illness conditions and mortality. Design: This was a staggered, pre-post quasi-experimental study designed to assess a multi-modal intervention (collaborative improvement meetings, audit and feedback, clinical mentoring) for improving quality of care following formal training in the management of severe illness in low-income settings. Results: From August 2014 to May 2015, 5759 patients were hospitalized, of whom 2451 (42.6%) had their HIV status assessed; 395 (16.1%) were HIV-infected. HIV-infected patients were significantly more likely to meet criteria for shock (27.5% vs. 15.1%, risk ratio [RR] 1.8, 95% confidence interval [CI] 1.7-1.9, P < 0.001) and severe respiratory distress (6.7% vs. 4.3%, RR 1.5, 95%CI 1.2-2.0, P < 0.001), and were significantly more likely to die in hospital (12.0% vs. 2.9%, RR 4.1, 95%CI 3.2-5.4, P < 0.001). There was no evidence of improved HIV status assessment during the intervention period (36.5% vs. 44.8%, +8.3%, 95%CI -8.3 to 24.8, P = 0.33). Conclusions: Hospitalized HIV-infected patients in western Uganda are at high risk for severe illness and death. Novel quality improvement strategies are needed to enhance hospital-based HIV testing in high-burden settings.

Biomarkers of Tuberculosis Severity and Treatment Effect: A Directed Screen of 70 Host Markers in a Randomized Clinical Trial

More efficacious treatment regimens are needed for tuberculosis, however, drug development is impeded by a lack of reliable biomarkers of disease severity and of treatment effect. We conducted a directed screen of host biomarkers in participants enrolled in a tuberculosis clinical trial to address this need. Serum samples from 319 protocol-correct, culture-confirmed pulmonary tuberculosis patients treated under direct observation as part of an international, phase 2 trial were screened for 70 markers of infection, inflammation, and metabolism. Biomarker assays were specifically developed for this study and quantified using a novel, multiplexed electrochemiluminescence assay. We evaluated the association of biomarkers with baseline characteristics, as well as with detailed microbiologic data, using Bonferroni-adjusted, linear regression models. Across numerous analyses, seven proteins, SAA1, PCT, IL-1β, IL-6, CRP, PTX-3 and MMP-8, showed recurring strong associations with markers of baseline disease severity, smear grade and cavitation; were strongly modulated by tuberculosis treatment; and had responses that were greater for patients who culture-converted at 8weeks. With treatment, all proteins decreased, except for osteocalcin, MCP-1 and MCP-4, which significantly increased. Several previously reported putative tuberculosis-associated biomarkers (HOMX1, neopterin, and cathelicidin) were not significantly associated with treatment response. In conclusion, across a geographically diverse and large population of tuberculosis patients enrolled in a clinical trial, several previously reported putative biomarkers were not significantly associated with treatment response, however, seven proteins had recurring strong associations with baseline radiographic and microbiologic measures of disease severity, as well as with early treatment response, deserving additional study.

Bioavailability and tolerability of nebulised dexamethasone sodium phosphate in adult horses

BACKGROUND

Nebulisation of the injectable dexamethasone sodium phosphate (DSP) would offer an inexpensive way of delivering a potent corticosteroid directly to the lungs of horses with asthma. However, this approach would be advantageous only if systemic absorption is minimal and if the preservatives present in the formulation do not induce airway inflammation.

OBJECTIVE

To investigate the bioavailability of nebulised DSP and determine whether it induces airway inflammation or hypothalamic-pituitary-adrenal (HPA) axis suppression in healthy adult horses.

STUDY DESIGN

Randomised crossover experiment.

METHODS

Dexamethasone sodium phosphate was administered to six healthy adult horses at a dose of 5 mg q. 24 h for 5 days via nebulised, or intravenous (i.v.) routes. Plasma dexamethasone concentrations were measured by UPLC/MS-MS to calculate bioavailability. Cytological examination of bronchoalveolar fluid was performed at baseline and after the last dose of DSP. A validated chemiluminescent immunoassay was used to measure basal serum cortisol concentrations.

RESULTS

After nebulisation to adult horses, dexamethasone had a mean (±s.d.) maximum plasma concentration of 0.774 ± 0.215 ng/mL and systemic bioavailability of 4.3 ± 1.2%. Regardless of route of administration, there was a significant decrease in the percentage of neutrophils in bronchoalveolar lavage fluid over time. During i.v. administration, basal serum cortisol concentration decreased significantly from baseline to Day 3 and remained low on Day 5. In contrast, basal serum cortisol concentration did not change significantly during administration via nebulisation.

MAIN LIMITATIONS

Small sample size and short period of drug administration.

CONCLUSIONS

Dexamethasone sodium phosphate administered via nebulisation had minimal systemic bioavailability and did not induce lower airway inflammation or HPA axis suppression in healthy horses.

Re-inventing adherence: toward a patient-centered model of care for drug-resistant tuberculosis and HIV

BACKGROUND

Despite renewed focus on molecular tuberculosis (TB) diagnostics and new antimycobacterial agents, treatment outcomes for patients co-infected with drug-resistant TB and human immunodeficiency virus (HIV) remain dismal, in part due to lack of focus on medication adherence as part of a patient-centered continuum of care.

OBJECTIVE

To review current barriers to drug-resistant TB-HIV treatment and propose an alternative model to conventional approaches to treatment support.

DISCUSSION

Current national TB control programs rely heavily on directly observed therapy (DOT) as the centerpiece of treatment delivery and adherence support. Medication adherence and care for drug-resistant TB-HIV could be improved by fully implementing team-based patient-centered care, empowering patients through counseling and support, maintaining a rights-based approach while acknowledging the responsibility of health care systems in providing comprehensive care, and prioritizing critical research gaps.

CONCLUSION

It is time to re-invent our understanding of adherence in drug-resistant TB and HIV by focusing attention on the complex clinical, behavioral, social, and structural needs of affected patients and communities.

Delusional Infestation in Parkinson's Disease

Delusional infestation (DI), a form of psychosis, has rarely been reported in patients with Parkinson disease (PD). The clinical presentation and successful treatment of DI is illustrated through 5 cases. Each patient developed DI during treatment for moderate to advanced Parkinson's disease, and only 2 had cognitive impairment. Two patients were on monotherapy: 1 on a dopamine agonist and the other on trihexyphenidyl. Three patients were receiving complex combination therapy with 2 to 5 different anti-Parkinsonian medications at the onset of their delusion. Selective discontinuation or reduction of these medications was key to the resolution of DI in each patient. Although the medication adjustments differed, the changes resulted in the reduction of anticholinergic effects or extracellular striatal dopamine levels. This series emphasizes the clinical features and management strategies for this disruptive form of psychosis in patients with PD.

Pathways and costs of care for patients with tuberculosis symptoms in rural Uganda

SETTING

Six district-level government health centers in rural Uganda and the surrounding communities.

OBJECTIVE

To determine pathways to care and associated costs for patients with chronic cough referred for tuberculosis (TB) evaluation in Uganda.

DESIGN

We conducted a cross-sectional study, surveying 64 patients presenting with chronic cough and undergoing first-time sputum evaluation at government clinics. We also surveyed a random sample of 114 individuals with chronic cough in surrounding communities. We collected information on previous health visits for the cough as well as costs associated with the current visit.

RESULTS

Eighty per cent of clinic patients had previously sought care for their cough, with a median of three previous visits (range 0-32, interquartile range [IQR] 2-5). Most (n = 203, 88%) visits were to a health facility that did not provide TB microscopy services, and the majority occurred in the private sector. The cost of seeking care for the current visit alone represented 28.8% (IQR 9.1-109.5) of the patients' median monthly household income.

CONCLUSION

Most patients seek health care for chronic cough, but do so first in the private sector. Engagement of the private sector and streamlining TB diagnostic evaluation are critical for improving case detection and meeting global TB elimination targets.

Impact of mycobacterial culture among HIV-infected adults with presumed TB in Uganda: a prospective cohort study

BACKGROUND

Implementation of new tuberculosis (TB) diagnostic strategies in resource-constrained settings is challenging. We measured the impact of solid and liquid mycobacterial cultures on treatment practices for patients undergoing TB evaluation in Kampala, Uganda.

METHODS

We enrolled consecutive smear-negative, human immunodeficiency virus positive adults with cough of ⩾2 weeks from September 2009 to April 2010. Laboratory technicians performed mycobacterial cultures on solid and liquid media. We compared empiric treatment decisions with solid and liquid culture in terms of diagnostic yield and time to results, and assessed impact on patient management.

RESULTS

Of 200 patients enrolled, 26 (13%) had culture-confirmed TB: 22 (85%) on solid culture alone, 2 (8%) on liquid culture alone, and 2 (8%) on both solid and liquid culture. Thirty-four patients received empiric anti-tuberculosis treatment, but only 10 (29%) were culture-positive. Median time to a positive result on solid culture was 92 days (interquartile range [IQR] 69-148) compared to 106 days (IQR 66-157) for liquid culture. No patients initiated treatment following a positive result on liquid culture.

CONCLUSION

The introduction of mycobacterial culture did not influence care for patients undergoing evaluation for TB in Kampala, Uganda. Attention to contextual factors surrounding implementation is needed to ensure the effective introduction of new testing strategies in low-income countries.

Pharmacokinetics and physiologic effects of alprazolam after a single oral dose in healthy mares

The objective of this study was to evaluate the pharmacokinetic properties and physiologic effects of a single oral dose of alprazolam in horses. Seven adult female horses received an oral administration of alprazolam at a dosage of 0.04 mg/kg body weight. Blood samples were collected at various time points and assayed for alprazolam and its metabolite, α-hydroxyalprazolam, using liquid chromatography/mass spectrometry. Pharmacokinetic disposition of alprazolam was analyzed by a one-compartmental approach. Mean plasma pharmacokinetic parameters (±SD) following single-dose administration of alprazolam were as follows: Cmax 14.76 ± 3.72 ng/mL and area under the curve (AUC0-∞ ) 358.77 ± 76.26 ng·h/mL. Median (range) Tmax was 3 h (1-12 h). Alpha-hydroxyalprazolam concentrations were detected in each horse, although concentrations were low (Cmax 1.36 ± 0.28 ng/mL). Repeat physical examinations and assessment of the degree of sedation and ataxia were performed every 12 h to evaluate for adverse effects. Oral alprazolam tablets were absorbed in adult horses and no clinically relevant adverse events were observed. Further evaluation of repeated dosing and safety of administration of alprazolam to horses is warranted.

Pharmacokinetics and pharmacodynamics of three formulations of firocoxib in healthy horses

The objectives of this study were to compare the pharmacokinetics and COX selectivity of three commercially available formulations of firocoxib in the horse. Six healthy adult horses were administered a single dose of 57 mg intravenous, oral paste or oral tablet firocoxib in a three-way, randomized, crossover design. Blood was collected at predetermined times for PGE2 and TXB2 concentrations, as well as plasma drug concentrations. Similar to other reports, firocoxib exhibited a long elimination half-life (31.07 ± 10.64 h), a large volume of distribution (1.81 ± 0.59L/kg), and a slow clearance (42.61 ± 11.28 mL/h/kg). Comparison of the oral formulations revealed a higher Cmax , shorter Tmax , and greater AUC for the paste compared to the tablet. Bioavailability was 112% and 88% for the paste and tablet, respectively. Maximum inhibition of PGE2 was 83.76% for the I.V. formulation, 52.95% for the oral paste formulation, and 46.22% for the oral tablet formulation. Pharmacodynamic modeling suggests an IC50 of approximately 27 ng/mL and an IC80 of 108 ng/ mL for COX2 inhibition. Inhibition of TXB2 production was not detected. This study indicates a lack of bioequivalence between the oral formulations of firocoxib when administered as a single dose to healthy horses.

Turtle utricle dynamic behavior using a combined anatomically accurate model and experimentally measured hair bundle stiffness

Anatomically correct turtle utricle geometry was incorporated into two finite element models. The geometrically accurate model included appropriately shaped macular surface and otoconial layer, compact gel and column filament (or shear) layer thicknesses and thickness distributions. The first model included a shear layer where the effects of hair bundle stiffness was included as part of the shear layer modulus. This solid model's undamped natural frequency was matched to an experimentally measured value. This frequency match established a realistic value of the effective shear layer Young's modulus of 16 Pa. We feel this is the most accurate prediction of this shear layer modulus and fits with other estimates (Kondrachuk, 2001b). The second model incorporated only beam elements in the shear layer to represent hair cell bundle stiffness. The beam element stiffness's were further distributed to represent their location on the neuroepithelial surface. Experimentally measured striola hair cell bundles mean stiffness values were used in the striolar region and the mean extrastriola hair cell bundles stiffness values were used in this region. The results from this second model indicated that hair cell bundle stiffness contributes approximately 40% to the overall stiffness of the shear layer-hair cell bundle complex. This analysis shows that high mass saccules, in general, achieve high gain at the sacrifice of frequency bandwidth. We propose the mechanism by which this can be achieved is through increase the otoconial layer mass. The theoretical difference in gain (deflection per acceleration) is shown for saccules with large otoconial layer mass relative to saccules and utricles with small otoconial layer mass. Also discussed is the necessity of these high mass saccules to increase their overall system shear layer stiffness. Undamped natural frequencies and mode shapes for these sensors are shown.

Sex disparities in tuberculosis suspect evaluation: a cross-sectional analysis in rural Uganda

SETTING

Six primary health care centers in rural Uganda.

OBJECTIVE

To compare the quality of tuberculosis (TB) evaluation for men and women presenting to primary health care facilities in high-burden settings.

DESIGN

Cross-sectional study using indicators derived from the International Standards of Tuberculosis Care (ISTC) to compare the quality of TB evaluation services provided to men and women.

RESULTS

Of 161 230 patient visits between January 2009 and December 2010, 112 329 (69.7%) were women. We considered 3308 (2.1%) patients with cough ≥2 weeks as TB suspects, of whom 1871 (56.6%) were women. Female TB suspects were less likely to be referred for sputum smear examination (45.9% vs. 61.6%, P < 0.001), to complete sputum smear examination if referred (73.7% vs. 78.3%, P = 0.024) and to receive comprehensive evaluation and care as defined by the ISTC (33.0% vs. 45.6%, P < 0.001). After adjusting for age, clinic site and visit date, women remained less likely to be referred for sputum smear examination (risk ratio [RR] 0.81, 95%CI 0.74-0.89, P < 0.001) and to receive ISTC-recommended care (RR 0.79, 95%CI 0.72-0.86, P < 0.001).

CONCLUSION

Strategies to ensure that women receive appropriate TB evaluation could provide a valuable opportunity for increasing case detection while also promoting equitable and universal access to care.

Intraocular lymphoma: a clinical perspective

Primary vitreoretinal lymphoma (PVRL) is a rare malignancy that is speculated to arise extraocularly, and preferentially invade and flourish in the ocular and CNS microenvironments. The eye is involved in about 20% of primary central nervous system lymphomas, but the brain is eventually involved in about 80% of PVRL. Most are B-cell lymphomas with small numbers of T-cell lymphomas metastatic to the vitreous and retina. Metastatic systemic B-cell lymphoma usually involves choroid. Primary choroidal lymphoma is rare. Intraocular lymphoma can usually be distinguished from uveitis clinically, although there are overlaps, which may be pronounced in eyes with a large component of reactive inflammation related to tumor surveillance and control. There are controversies in diagnosis and treatment. Diagnosis through examination of ocular fluid is technically difficult and can utilize cytology, immunohistochemistry, flow cytometry, molecular detection of gene rearrangements, and cytokine profiling. Treatment of intraocular lymphoma without detectable CNS disease could consist of a full course of systemic chemotherapy with ocular adjunctive treatment, or ocular treatment alone depending on the preference of the clinical center. In ocular only cases where the vitreous has been debulked to improve vision and there is no sight-threatening involvement of the RPE, orbital irradiation or intravitreal chemotherapy stabilizes the intraocular process but does not seem to modify the CNS component, which can present symptomatically in an advanced state. This is a highly malignant disease with a poor prognosis. Close collaboration with a pathologist and oncologist, and good communication with patients is essential.

A high-field adiabatic fast passage ultracold neutron spin flipper for the UCNA experiment

The UCNA collaboration is making a precision measurement of the β asymmetry (A) in free neutron decay using polarized ultracold neutrons (UCN). A critical component of this experiment is an adiabatic fast passage neutron spin flipper capable of efficient operation in ambient magnetic fields on the order of 1 T. The requirement that it operate in a high field necessitated the construction of a free neutron spin flipper based, for the first time, on a birdcage resonator. The design, construction, and initial testing of this spin flipper prior to its use in the first measurement of A with UCN during the 2007 run cycle of the Los Alamos Neutron Science Center's 800 MeV proton accelerator is detailed. These studies determined the flipping efficiency of the device, averaged over the UCN spectrum present at the location of the spin flipper, to be ̅ε=0.9985(4).

Diagnostic dilemmas in retinitis and endophthalmitis

Visual loss in infectious posterior uveitis or panuveitis can occur if proper therapy is delayed because of diagnostic uncertainty. Some disorders, such as acute retinal necrosis and bacterial endophthalmitis, can be rapidly progressive, and therefore require prompt and accurate diagnosis to guide initial therapy. Other more slowly evolving infections, such as toxoplasmic chorioretinitis or fungal endophthalmitis, can be worsened by empiric use of corticosteroids without specific antimicrobial coverage. Key ocular diagnostic features are helpful but highly variable with overlap with both non-infectious uveitis and neoplastic masquerades, even for key signs such as hypopyon. Close examination of the fundus with attention to color, location, size, border, and opacity of lesions and associated arteriolitis or frosted branch angiitis is helpful in the diagnosis of chorioretinitis. Ultrasonography is an important tool in the evaluation of eyes with suspected endophthalmitis, especially those with intracapsular infection or focal infected deposits. Testing of intraocular fluid can be extremely useful but suffers from inaccessibility, poor sensitivity, and test selections dependent on a presumptive diagnosis, which may be wrong. The dilemma for clinician is to make the correct diagnosis of a rare, blinding, variegated disease quickly enough to intercede with specific therapy or to apply empiric therapy in a sufficiently skilled manner to avert disaster and confirm the diagnosis by response to treatment. When non-infectious uveitis is in the differential, empiric corticosteroids must sometimes be used, at great risk, if clinical examination, ancillary testing, and any available intraocular diagnostic tests have failed to confirm a diagnosis.

Chest radiographic findings of pulmonary tuberculosis in severely immunocompromised patients with the human immunodeficiency virus

OBJECTIVE

We describe chest radiograph (CXR) findings in a population with a high prevalence of human immunodeficiency virus (HIV) and tuberculosis (TB) in order to identify radiological features associated with TB; to compare CXR features between HIV-seronegative and HIV-seropositive patients with TB; and to correlate CXR findings with CD4 T-cell count.

METHODS

Consecutive adult patients admitted to a national referral hospital with a cough of duration of 2 weeks or longer underwent diagnostic evaluation for TB and other pneumonias, including sputum examination and mycobacterial culture, bronchoscopy and CXR. Two radiologists blindly reviewed CXRs using a standardised interpretation form.

RESULTS

Smear or culture-positive TB was diagnosed in 214 of 403 (53%) patients. Median CD4+ T-cell count was 50 cells mm(-3) [interquartile range (IQR) 14-150]. TB patients were less likely than non-TB patients to have a normal CXR (12% vs 20%, p = 0.04), and more likely than non-TB patients to have a diffuse pattern of opacities (75% vs 60%, p = 0.003), reticulonodular opacities (45% vs 12%, p < 0.001), nodules (14% vs 6%, p = 0.008) or cavities (18% vs 7%, p = 0.001). HIV-seronegative TB patients more often had consolidation (70% vs 42%, p = 0.007) and cavities (48% vs 13%, p < 0.001) than HIV-seropositive TB patients. TB patients with a CD4+ T-cell count of ≤ 50 cells mm(-3) less often had consolidation (33% vs 54%, p = 0.006) and more often had hilar lymphadenopathy (30% vs 16%, p = 0.03) compared with patients with CD4 51-200 cells mm(-3).

CONCLUSION

Although different CXR patterns can be seen in TB and non-TB pneumonias there is considerable overlap in features, especially among HIV-seropositive and severely immunosuppressed patients. Providing clinical and immunological information to the radiologist might improve the accuracy of radiographic diagnosis of TB.

Pharmacokinetics of pioglitazone after multiple oral dose administration in horses

Pioglitazone is a thiazolidinedione class of antidiabetic agent with proven efficacy in increasing insulin sensitivity in humans with noninsulin-dependent diabetes mellitus, a syndrome of insulin resistance sharing similarities with equine metabolic syndrome. The purpose of this study was to determine the pharmacokinetics of pioglitazone in adult horses following multiple oral dose administration. Pioglitazone hydrochloride (1 mg/kg) was administered orally for 11 doses at 24-h intervals, and plasma samples were collected. Initially, a pilot study was performed using one horse; and thereafter the drug was administered to six horses. Samples were analyzed by liquid chromatography with tandem mass spectrometry, and pharmacokinetic parameters were calculated using noncompartmental modeling. The maximum plasma concentration was 509.1 ± 413.5 ng/mL achieved at 1.88 ± 1.39 h following oral administration of the first dose, and 448.1 ± 303.5 ng/mL achieved at 2.83 ± 1.81 h (mean ± SD) following the eleventh dose. Apparent elimination half-life was 9.94 ± 4.57 and 9.63 ± 5.33 h after the first and eleventh dose, respectively. This study showed that in healthy horses, pioglitazone administered at a daily oral dose of 1 mg/kg results in plasma concentrations and total drug exposure approximating, but slightly below, those considered therapeutic in humans.

A parent advice package for family shopping trips: development and evaluation

THIS ARTICLE REPORTS ON THE PRIMARY STEPS IN THE DEVELOPMENT OF PARENT ADVICE FOR POPULAR DISSEMINATION: (a) developing advice for one specific problem situation, family shopping trips; (b) testing the advice program for benefit to children and convenience to adults; and (c) packaging the advice so it can be used successfully by interested parents. Systematic observation of 12 families using the written advice package on shopping trips revealed its effectiveness in reducing child disruptions and increasing positive interactions between parents and children. These findings, along with interview information from families, showed that the package is usable, effective, and popular with both parents and children, and thus is ready for dissemination to a wide audience of parents-a step that in itself should involve research and evaluation.

Efficacy and pharmacokinetics of pantoprazole in alpacas

BACKGROUND

Despite frequent clinical use, information about the pharmacokinetics and efficacy of pantoprazole in camelids is not available.

OBJECTIVES

To examine the pharmacokinetics of both IV and SC pantoprazole and to determine whether pantoprazole administration would increase 3rd compartment pH in alpacas.

ANIMALS

Six healthy adult alpacas.

METHODS

Alpacas were fitted with a 3rd compartment cannula for measuring gastric pH. After recovery, alpacas received 1 mg/kg pantoprazole IV, q24h for 3 days or 2 mg/kg SC q24h for 3 days. Alpacas received both IV and SC pantoprazole, with a minimum of 3 weeks between treatments. Third compartment pH was recorded and plasma samples were taken for pharmacokinetic analysis.

RESULTS

Pantoprazole induced a slow but sustained increase in 3rd compartment pH when given by both the IV and SC routes. Third compartment pH was significantly increased as compared with baseline values (1.81+/-0.7; mean+/-SD) at 24 (2.47+/-0.8), 48 (3.53+/-1.0) and 72 hours (4.03+/-1.3) after daily IV administration of pantoprazole. Third compartment pH increased from 1.73+/-0.6 at baseline to 3.05+/-1.1, 4.02+/-1.4, and 3.61+/-1.6 at 24, 48, and 72 hours after SC administration, respectively. Pharmacokinetic analysis demonstrated that pantoprazole had a short elimination half-life (0.47+0.06 h) and a high clearance rate (12.2+/-2.9 mL/kg/min) after both IV and SC administration.

CONCLUSIONS AND CLINICAL RELEVANCE

Based on the results of this study, pantoprazole represents a safe and effective drug for increasing 3rd compartment pH in camelids. Either IV or SC administration is likely to be an effective treatment for gastric ulcers.

Predicting mortality from HIV-associated Pneumocystis pneumonia at illness presentation: an observational cohort study

BACKGROUND

Although the use of antiretroviral therapy has led to dramatic declines in AIDS-associated mortality, Pneumocystis pneumonia (PCP) remains a leading cause of death in HIV-infected patients.

OBJECTIVES

To measure mortality, identify predictors of mortality at time of illness presentation and derive a PCP mortality prediction rule that stratifies patients by risk for mortality.

METHODS

An observational cohort study with case note review of all HIV-infected persons with a laboratory diagnosis of PCP at San Francisco General Hospital from 1997 to 2006.

RESULTS

451 patients were diagnosed with PCP on 524 occasions. In-hospital mortality was 10.3%. Multivariate analysis identified five significant predictors of mortality: age (adjusted odds ratio (AOR) per 10-year increase, 1.69; 95% CI 1.08 to 2.65; p = 0.02); recent injection drug use (AOR 2.86; 95% CI 1.28 to 6.42; p = 0.01); total bilirubin >0.6 mg/dl (AOR 2.59; 95% CI 1.19 to 5.62; p = 0.02); serum albumin <3 g/dl (AOR 3.63; 95% CI 1.72-7.66; p = 0.001); and alveolar-arterial oxygen gradient >or=50 mm Hg (AOR 3.02; 95% CI 1.41 to 6.47; p = 0.004). Using these five predictors, a six-point PCP mortality prediction rule was derived that stratifies patients according to increasing risk of mortality: score 0-1, 4%; score 2-3, 12%; score 4-5, 48%.

CONCLUSIONS

The PCP mortality prediction rule stratifies patients by mortality risk at the time of illness presentation and should be validated as a clinical tool.

Sensitivity and specificity of fluorescence microscopy for diagnosing pulmonary tuberculosis in a high HIV prevalence setting

SETTING

Mulago Hospital, Kampala, Uganda.

OBJECTIVE

To evaluate the diagnostic performance of fluorescence microscopy (FM) for diagnosing pulmonary tuberculosis (TB) in a high human immunodeficiency virus (HIV) prevalence setting.

DESIGN

Consecutive in-patients with cough for >2 weeks submitted two sputum specimens for smear microscopy. Smears were examined by conventional light microscopy (CM) and FM. The performance of the two methods was compared using mycobacterial culture as a reference standard.

RESULTS

A total of 426 patients (82% HIV-infected) were evaluated. FM identified 11% more smear-positive patients than CM (49% vs. 38%, P < 0.001). However, positive FM results were less likely than positive CM results to be confirmed by culture when smears were read as either 'scanty' (54% vs. 90%, P < 0.001) or 1+ (82% vs. 91%, P = 0.02). Compared to CM, the sensitivity of FM was higher (72% vs. 64%, P = 0.005), and the specificity lower (81% vs. 96%, P < 0.001). In receiver operating characteristic analysis, maximum area under the curve for FM was obtained at a threshold of >4 acid-fast bacilli/100 fields (sensitivity 68%, specificity 90%).

CONCLUSION

Although FM increases the sensitivity of sputum smear microscopy, additional data on FM specificity and on the clinical consequences associated with false-positive FM results are needed to guide implementation of this technology in high HIV prevalence settings.

A comparison of probabilistic and stochastic formulations in modelling growth uncertainty and variability

We compare two approaches for inclusion of uncertainty/variability in modelling growth in size-structured population models. One entails imposing a probabilistic structure on growth rates in the population while the other involves formulating growth as a stochastic Markov diffusion process. We present a theoretical analysis that allows one to include comparable levels of uncertainty in the two distinct formulations in making comparisons of the two approaches.

Ocular toxicity and distribution of subconjunctival and intravitreal rapamycin in horses

In vitro photosensitivity of rapamycin (RAPA) and ocular toxicity and distribution of intravitreal and subconjunctival RAPA was evaluated in normal horses. RAPA (2.5 mg, 5 mg, and 10 mg) was placed in 10 mL of PBS and maintained in a water bath at 37 degrees C, kept in the dark or subjected to room light, and sampled for up to 3 months for RAPA levels. Six normal adult horses received either 5 mg (n = 2) or 10 mg (n = 2) of RAPA intravitreally or 10 mg (n = 2) subconjunctivally. Ophthalmic exams and electroretinography (ERG) were performed prior to injection and on days 1, 7, 14, and 21 post-injection. Eyes were enucleated and samples were collected for RAPA concentrations and histopathology. No difference in light vs. dark RAPA concentrations was observed, suggesting a lack of RAPA phototoxicity. No evidence of ocular toxicity was noted on ophthalmic examination or histopathology. RAPA was not detected intraocularly 7 days post-injection in eyes receiving subconjunctival RAPA, but was detected in the vitreous at 21 days post-injection. Drug could be detected in both the aqueous and vitreous humor after intravitreal injection. Further study is needed to determine the efficacy of intravitreal RAPA.

Recombinant human G-CSF increases invasiveness of breast cancer cells

Abstract #4057

Background: Recombinant human granulocyte-colony stimulating factor (rhG-CSF) is commonly given to breast cancer patients to prevent neutropenia during chemotherapy. It binds to the G-CSF receptor (G-CSFR) on neutrophil precursors, promoting their proliferation within the bone marrow. We observed breast cancer growth in patients with advanced breast cancer during rhG-CSF administration. The G-CSFR is present on some solid tumors, but has not been examined in breast cancer. We asked whether breast cancer cells express the G-CSFR, and whether rhG-CSF has any direct effects on breast cancer proliferation or invasion in vitro.&#x2028; Material and Methods: MDA MB231 is a highly aggressive ER–PR–Her2/neu– breast cancer cell line derived from a human pleural effusion. We analyzed this cell line for the presence of the G-CSFR by immunohistochemistry, reverse-transcriptase PCR (RT-PCR), Western Blot analysis and flow cytometry. We sequenced DNA products of RT-PCR to verify results. We examined the effects of physiologic doses of rhG-CSF on breast cancer cell proliferation and invasion using MTT proliferation and Matrigel transwell assays, respectively.&#x2028; Results: MDA MB231 breast cancer cells express G-CSFR protein and mRNA. Of seven known G-CSFR isoforms, we found evidence of isoforms 1 and 4. Treating MDA MB231 breast cancer cells with rhG-CSF at 50ng/ml did not increase cell proliferation, but did increase invasion across a Matrigel-coated transwell membrane. Cells treated with rhG-CSF appeared more stellate than untreated cells. Studies are ongoing to evaluate which signal transduction pathways and genes are involved in this increased invasion response. The effects of rhG-CSF on breast cancer growth in vivo are also being examined in murine models.&#x2028; Discussion: rhG-CSF is given routinely as part of many adjuvant chemotherapy regimens for breast cancer. Although dose-dense regimens using rhG-CSF have shown equivalent or improved survival when compared to standard dosing regimens, it is possible that rhG-CSF may increase the growth or invasive potential of some breast cancers. It is also possible that rhG-CSF could mobilize breast cancer cells from the bone marrow, making these cells more susceptible to chemotherapy. These possibilities should promote thoughful use of rhG-CSF in the clinical setting, and should factor into the design and implementation of clinical trials using rhG-CSF.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4057.

Attenuation of ischaemic injury in the equine jejunum by administration of systemic lidocaine

REASONS FOR PERFORMING STUDY

Absorption of endotoxin across ischaemic-injured mucosa is a major cause of mortality after colic surgery. Recent studies have shown that flunixin meglumine retards mucosal repair. Systemic lidocaine has been used to treat post operative ileus, but it also has novel anti-inflammatory effects that could improve mucosal recovery after ischaemic injury.

HYPOTHESIS

Systemic lidocaine ameliorates the deleterious negative effects of flunixin meglumine on recovery of mucosal barrier function.

METHODS

Horses were treated i.v. immediately before anaesthesia with either 0.9% saline 1 ml/50 kg bwt, flunixin meglumine 1 mg/kg bwt every 12 h or lidocaine 1.3 mg/kg bwt loading dose followed by 0.05 mg/kg bwt/min constant rate infusion, or both flunixin meglumine and lidocaine, with 6 horses allocated randomly to each group. Two sections of jejunum were subjected to 2 h of ischaemia by temporary occlusion of the local blood supply, via a midline celiotomy. Horses were monitored with a behavioural pain score and were subjected to euthanasia 18 h after reversal of ischaemia. Ischaemic-injured and control jejunum was mounted in Ussing chambers for measurement of transepithelial electrical resistance (TER) and permeability to lipopolysaccharide (LPS).

RESULTS

In ischaemic-injured jejunum TER was significantly higher in horses treated with saline, lidocaine or lidocaine and flunixin meglumine combined, compared to horses treated with flunixin meglumine. In ischaemic-injured jejunum LPS permeability was significantly increased in horses treated with flunixin meglumine alone. Behavioural pain scores did not increase significantly after surgery in horses treated with flunixin meglumine.

CONCLUSIONS

Treatment with systemic lidocaine ameliorated the inhibitory effects of flunixin meglumine on recovery of the mucosal barrier from ischaemic injury, when the 2 treatments were combined. The mechanism of lidocaine in improving mucosal repair has not yet been elucidated.