Impact of different hand-drying methods on surrounding environment: aerosolization of virus and bacteria, and transfer to surfaces

BACKGROUND

In recent years, hand drying has been highlighted as a key step in appropriate hand hygiene, as moisture on hands can increase the transfer of micro-organisms from hands to surfaces and vice versa.

AIM

To understand bacterial and viral aerosolization following hand drying, and study the transfer of micro-organisms from hands to surfaces after drying using different methods.

METHODS

Groups of five volunteers had their hands pre-washed with soap, rinsed and dried, then inoculated with a concentrated mixture of Pseudomonas fluorescens and MS2 bacteriophage. Volunteers entered an empty washroom, one at a time, and rinsed their hands with water or washed their hands with soap prior to drying with a jet dryer or paper towels. Each volunteer applied one hand successively to various surfaces, while their other hand was sampled using the glove juice method. Both residual bacteria and viruses were quantified from the washroom air, surface swabs and hand samples.

FINDINGS

P. fluorescens and MS2 bacteriophages were rarely aerosolized while drying hands for any of the drying methods studied. Results also showed limited, and similar, transfer of both micro-organisms studied on to surfaces for all drying methods.

CONCLUSION

The use of jet dryers or paper towels produces low levels of aerosolization when drying hands in a washroom. Similarly, all drying methods result in low transfer to surfaces. While the coronavirus disease 2019 pandemic raised concerns regarding public washrooms, this study shows that all methods tested are hygienic solutions for dry washed hands.

The use of rats to detect drug-resistant TB

Although detection of drug-susceptible TB by Anti-Persoonsmijnen Ontmijnende Product Ontwikkeling-trained African giant pouched rats has been known for more than a decade, the detection of drug-resistant TB (DR-TB) using rats has never been explored before. We present what we believe to be the first report on rifampicin-resistant TB (RR-TB) detected using Xpert® MTB/RIF Ultra, comparably identified by rats sniffing sputum samples from presumptive TB patients: 88% of RR-TB detected using Ultra were identified by the rats. Further evaluation of the usefulness of rats for large-scale DR-TB contact triage testing is needed, especially in low- and middle-income countries, where resources are limited.

Dolutegravir resistance in Malawi’s national HIV treatment program

Dolutegravir HIV drug resistance (HIVDR) data from Africa remain sparse. We reviewed HIVDR results of Malawians on dolutegravir-based antiretroviral therapy (November 2020–September 2021). Of 6462 eligible clients, 33 samples were submitted to South Africa, 27 were sequenced successfully, and 8 (30%) had dolutegravir HIVDR. Malawi urgently requires adequate HIVDR testing capacity.

No-slip billiards with particles of variable mass distribution

Astute variations in the geometry of mathematical billiard tables have been and continue to be a source of understanding their wide range of dynamical behaviors, from regular to chaotic. Viewing standard specular billiards in the broader setting of no-slip (or rough) collisions, we show that an equally rich spectrum of dynamics can be called forth by varying the mass distribution of the colliding particle. We look at three two-parameter families of billiards varying both the geometry of the table and the particle, including as special cases examples of standard billiards demonstrating dynamics from integrable to chaotic, and show that markedly divergent dynamics may arise by changing only the mass distribution. Furthermore, for certain parameters, billiards emerge, which display unusual dynamics, including examples of full measure periodic billiards, conjectured to be nonexistent for the standard billiards in Euclidean domains.

High Likelihood of Accepting COVID-19 Vaccine in a Latinx Community at High SARS-CoV-2 Risk in San Francisco

Of 4133 persons surveyed at a low-barrier coronavirus disease 2019 (COVID-19) test site with high positivity in an urban Latinx community in January 2021, 86% indicated that they would accept a COVID-19 vaccination. The top reasons for vaccine hesitancy included concerns around side effects and safety and distrust of health care systems.

AB0034 PD-1 AGONISM INHIBITS ACTIVATION OF PLASMACYTOID DENDRITIC CELLS

Background:

T cell function is regulated by complex signaling networks of interconnected activators and inhibitors. Blockade of inhibitory receptors such as programmed death-1 (PD-1) has emerged as a novel treatment for multiple forms of cancer. One of the most common adverse events associated with blockade of the endogenous PD-1/PD-L1 pathway is the induction of autoimmune pathology in multiple tissues, demonstrating that PD-1 activation is necessary for normal immune homeostasis in humans (Kostine, et al., 2018). Given this body of clinical data, we sought to develop a PD-1 agonist antibody as a therapeutic approach to restore immune homeostasis in patients living with autoimmune diseases. PD-1 expression and function has been primarily described on T cells (Ishida, et al., 1992), with additional data available from several other immune cell populations (Ohaegbulam, et al., 2015).

Objectives:

To study the effect of PD-1 agonism on plasmacytoid dendritic cell (pDC) function.

Methods:

Human PBMCs stimulated with or without toll-like receptor (TLR)-9 agonist, CpG were analyzed by flow cytometry for PD-1 expression on immune cell subsets. To assess the impact of PD-1 agonist on pDC function human PBMCs were activated by CpG in the presence or absence of PD-1 agonist. Type-I interferon (IFN) levels were quantified using ELISA from culture supernatants. The expression of interferon stimulated genes was analyzed by qPCR as a measure of type-I IFN activation.

Results:

We have discovered that TLR9 activation can induce PD-1 expression on plasmacytoid dendritic cells, which has not been previously reported. Further, we have demonstrated that PD-1 agonism inhibits TLR9-mediated activation and the effector functions of plasmacytoid dendritic cells.

Conclusion:

These data suggest the potential of PD-1 as a target for regulating diseases with pathology generated by type-I IFN.

References:

[1]Ishida, Y., Agata, Y., Shihibahara, K., & Honjo, T. (1992). Induced expression of PD-1, a novel member of the immunoglobulin gene superfamily, upon programmed cell death. EMBO J., 11(11):3887-95.

[2]Kostine, M., Rouxel, L., Barnetche, T., Veillon, R., Martin, F., Dutriaux, C., . . . Schaeverbeke, T. (2018). Rheumatic disorders associated with immune checkpoint inhibitors in patients with cancer-clinical aspects and relationship with tumour response: a single-centre prospective cohort study. Annual Rheumatic Disease, 77(3):393-398.

[3]Ohaegbulam, K. C., Assal, A., Lazar-Molnar, E., Yao, Y., & Zang, X. (2015). Human cancer immunotherapy with antibodies to the PD-1 and PD-L1 pathway. Trends in Molecular Medicine, 21(1); 24-33.

Disclosure of Interests:

Ishita Banerjee Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Lindsay Edwards Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Patrick Halvey Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Salvatore Alioto Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, David Cluckley Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Caitlin Mitchell Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Christopher Cox Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Emily Lurier Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Michael Cianci Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Soumya Bengeri Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Susmita Borthakur Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Katalin Kis-Toth Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Nathan Higginson-Scott Shareholder of: Pandion Therapeutics, Consultant of: Biotech Companies, Employee of: Pandion Therapeutics, Jo Viney Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics, Kevin L. Otipoby Shareholder of: Pandion Therapeutics, Employee of: Pandion Therapeutics

The COVID-19 Symptom to Isolation Cascade in a Latinx Community: A Call to Action

Background

Rapid coronavirus disease 2019 (COVID-19) diagnosis and isolation of infectious persons are critical to stopping forward transmission, and the care cascade framework can identify gaps in the COVID-19 response.

Methods

We described a COVID-19 symptom to isolation cascade and barriers among symptomatic persons who tested polymerase chain reaction positive for severe acute respiratory disease coronavirus 2 (SARS-CoV-2) at a low-barrier testing site serving a low-income Latinx community in San Francisco. Steps in the cascade are defined as days from symptom onset to test, test to result, and result to counseling on self-isolation. We examined SARS-CoV-2 cycle threshold (Ct) values to assess the likelihood of infectiousness on the day of testing and during missed isolation days.

Results

Among 145 persons, 97% were Latinx and 81% had an income of <$50000. The median time from symptom onset to isolation (interquartile range [IQR]) was 7 (5–10) days, leaving a median (IQR) of 3 (0–6) days of isolation. Eighty-three percent had moderate to high levels of virus (Ct <33), but by disclosure 23% were out of their isolation period. The longest intervals were symptom onset to test (median [IQR], 4 [2–9] days) and test to results notification (median [IQR], 3 [2–4] days). Access to a test site was the most common barrier to testing, and food and income loss was the most common barrier to isolation.

Conclusions

Over half of the 10-day isolation period passed by the time of disclosure, and over a fifth of people were likely outside the window of infectiousness by the time they received results. Improvements in test access and turnaround time, plus support for isolation, are needed for epidemic control of SARS-CoV-2 in highly impacted communities.

Field performance and public health response using the BinaxNOW TM Rapid SARS-CoV-2 antigen detection assay during community-based testing

Among 3,302 persons tested for SARS-CoV-2 by BinaxNOW TM and RT-PCR in a community setting, rapid assay sensitivity was 100%/98.5%/89% using RT-PCR Ct thresholds of 30, 35 and none. The specificity was 99.9%. Performance was high across ages and those with and without symptoms. Rapid resulting permitted immediate public health action.

Investigation of the correlation between college students’ success with stoichiometry subproblems and metacognitive awareness

The development of problem-solving skills — particularly with stoichiometry concepts — is paramount for succeeding in a general chemistry sequence. Key concepts related to problem solving and stoichiometry were analyzed and reported in this paper. The study analyzed retention of stoichiometry concepts over two consecutive quarters, the correlations between metacognition and success, and the correlations between the COSINE (Coding System for Investigating Subproblems and the Network) codes with the categories measured by the Metacognitive Awareness Inventory (MAI). Two cohorts, identified as the general and focus groups, were evaluated in the study. The general group (n = 39) took MAI in the Fall quarter and completed one multi-step question as a part of their regular exam. Concurrently, the focus group (n = 20) participated in a think-aloud session in which they solved six stoichiometry questions. Using a 95% confidence level, statistical differences between the fall and winter problem-solving performances were observed with the focus group. Furthermore, statistically significant correlations (using a 95% level of confidence) were observed between the MAI categories and the COSINE codes.

Outcome of Weekly Carboplatin-Paclitaxel-based Definitive Chemoradiation in Oesophageal Cancer in Patients Not Considered to be Suitable for Platinum-Fluoropyrimidine-based Treatment: A Multicentre, Retrospective Review

AIMS

Although cisplatin-fluoropyrimidine-based definitive chemoradiotherapy (dCRT) is a standard of care for oesophageal cancer, toxicity is significant and limits its use in elderly and frail patients. Weekly carboplatin-paclitaxel-based dCRT provides a viable alternative, although prospective data are lacking in the dCRT setting. Here we report the results of a national, multicentre retrospective review of outcome in patients treated with weekly carboplatin-paclitaxel-based dCRT.

MATERIALS AND METHODS

In this multicentre retrospective study of nine radiotherapy centres across the UK we evaluated the outcome of patients who had non-metastatic, histologically confirmed carcinoma of the oesophagus (adenocarcinoma, squamous cell or undifferentiated; World Health Organization performance status 0-2; stage I-III disease) and had been selected to receive weekly carboplatin-paclitaxel-based dCRT as they were considered not suitable for cisplatin-fluoropyrimidine-based dCRT. dCRT consisted of carboplatin AUC 2 and paclitaxel 50 mg/m2 (days 1, 8, 15, 22, 29) and the recommended radiation dose was 50 Gy in 25 daily fractions. We assessed overall survival, progression-free survival (PFS; overall, local and distant), proportion of patients who were failure free at the response assessment (12 weeks after dCRT), treatment compliance and toxicity.

RESULTS

In total, 214 patients from nine UK centres were treated between 15 February 2013 and 19 March 2019: 39.7% of patients were ≥75 years; 18.7% ≥ 80 years. Indications for weekly carboplatin-paclitaxel-based dCRT were comorbidities (47.2%), clinician choice (36.4%) and poor tolerance/progression on cisplatin-fluoropyrimidine induction chemotherapy (15.8%). The median overall survival was 24.28 months (95% confidence interval 20.07-30.09) and the median PFS was 16.33 months (95% confidence interval 14.29-20.96). Following treatment, 69.1% (96/139) had a combined complete response on endoscopy with non-progression (complete response/partial response/stable disease) on imaging. The 1- and 2-year overall survival rates for this patient group were 81.9% (95% confidence interval 75.6-86.8%) and 50.6% (95% confidence interval 40.5-60.0%), respectively. Thirty-three per cent (n = 70) of patients experienced at least one grade 3 + acute toxicity (grade 3/4 haematological: 10%; grade 3/4 non-haematological: 32%) and there were no treatment-related deaths. 86.9% of patients completed at least four cycles of concomitant weekly carboplatin-paclitaxel-based chemotherapy and planned radiotherapy was completed in 97.7% (209/214).

CONCLUSION

Weekly carboplatin-paclitaxel-based CRT seems to be well tolerated in elderly patients and in those with comorbidities, where cisplatin-fluoropyrimidine-based dCRT is contraindicated. Survival outcomes are comparable with cisplatin-fluoropyrimidine-based dCRT.

Method Extension Study to Validate Applicability of AOAC Official Method 996.14 Assurance® Polyclonal Enzyme Immunoassay for Detection of Listeria monocytogenes and Related Listeria spp. from Environmental Surfaces: Collaborative Study

Test portions from 3 environmental surface types, representative of typical surfaces found in a food production facility, were analyzed by the Assurance®Listeria Polyclonal Enzyme Immunoassay (EIA) and the U.S. Department of Agriculture/Food Safety and Inspection Service (USDA/FSIS) culture method for Listeria monocytogenes and related Listeria species. In all cases, naturally contaminated environmental test samples were collected from an actual food production facility by sponge or swab. Test samples from concrete surfaces were collected by both swab and sponge; sponge test samples were collected from rubber surfaces, and swabs were used to sample steel surfaces. Test portions from each surface type were simultaneously analyzed by both methods. A total of 23 collaborators, representing government agencies, as well as private industry in both the United States and Canada, participated in the study. During this study, a total of 550 test portions and controls was analyzed and confirmed, of which 207 were positive and 336 were negative by both methods. Six test portions were positive by culture, but negative by the EIA. Three test portions were negative by culture, but positive by the EIA. Two test portions were negative by EIA and by culture, but confirmed positive when EIA enrichment broths were subcultured to selective agars. The data reported here indicate that the Assurance®Listeria EIA method and the USDA/FSIS culture method are statistically equivalent for detection of L. monocytogenes and related Listeria species from environmental surfaces taken by sponges or swabs.

Method Extension Study to Validate Applicability of AOAC Official Method 997.03 Visual Immunoprecipitate Assay (VIP®) for Listeria monocytogenes and Related Listeria spp. from Environmental Surfaces: Collaborative Study

Test portions from 3 environmental surface types, representative of typical surfaces found in a food production facility, were analyzed by the Visual Immunoprecipitate assay (VIP®) and the U.S. Department of Agriculture/Food Safety and Inspection Service (USDA/FSIS) culture method for Listeria monocytogenes and related Listeria species. In all cases, naturally contaminated environmental test samples were collected from an actual food production facility by sponge or swab. Test samples from concrete surfaces were collected by both swab and sponge; sponge test samples were collected from rubber surfaces, and swabs were used to sample steel surfaces. Test portions from each surface type were simultaneously analyzed by both methods. A total of 27 laboratories, representing government agencies as well as private industry in both the United States and Canada, participated in the study. During this study, a total of 615 test portions and controls was analyzed and confirmed, of which 227 were positive and 378 were negative by both methods. Nine test portions were positive by culture, but negative by the VIP. Five test portions were negative by culture, but positive by the VIP. Four test portions were negative by VIP and by culture, but confirmed positive when VIP enrichment broths were subcultured to selective agars. The data reported here indicate that the VIP method and the USDA/FSIS culture method are statistically equivalent for detection of L. monocytogenes and related Listeria species from environmental surfaces taken by sponges or swabs.

Abstract PD8-04: Neoadjuvant chemotherapy for breast cancer: Nodal downstaging is highly correlated with pathological complete response

Background: Neoadjuvant chemotherapy (NAC) is employed in patients with larger tumors to attempt to downstage locally advanced cancers to allow breast conservation and to assess in vivo tumor response. The Multi-Institutional Neoadjuvant Therapy MammaPrint Project I (MINT) study asked a secondary question of whether complete nodal downstaging could also be achieved with NAC.

Methods: This analysis included 147 eligible invasive breast cancer patients with high tumor burdens, classified as cT2-4N0-3M0 (T2 greater than 3.5cm if N0). Patients who had a positive core biopsy and/or fine needle aspiration (FNA) on an axillary node prior to starting NAC were included in this analysis. Those who had a surgical sentinel lymph node biopsy were not included. Nodal involvement was established following neoadjuvant treatment by axillary lymph node dissection (ALND).

Results: This population was 54% postmenopausal, average age 53 yrs (range 25 to 80 yrs). Tumor characteristics were 91% invasive ductal carcinoma; 65% T2, 29% T3, 6% T4; 87% LN1, 13% LN2-3; 3% low grade, 38% intermediate grade, 59% high grade; 65% ER-positive, 49% PR-positive, and 28% HER2-positive by immunohistochemistry; 84% High Risk (HR) and 16% Low Risk (LR) by MammaPrint (MP). After NAC, 45% (66/147) of these LN-positive patients were down-staged to ypN0 and also achieved a complete pathological response in the primary tumor. The potential for down-staging was inversely-related to tumor burden, where 47% (60/128) of N1, 35% (6/17) of N2, and 0% (0/2) of N3 patients were down-staged to ypN0. There were 3 patients who were down-staged (2 N2 to N1, and 1 N3 to N2), but not to ypN0. At surgery, 34% (44/128) of patients had no change, and 19% (24/129) progressed in LN staging.

Pre vs Post NAC Nodal StagePre NAC Nodal StageypN0ypN1ypN2ypN3TotalcN16044222128cN2626317cN3  112Total6646296147

Conclusions: We confirmed that upon achieving a complete response of the primary tumor that there was also a pathologic complete response in the LN. About 53% of patients had no change or progression of LN involvement following NAC.

Citation Format: Blumencranz P, Habibi M, Treece T, Blumencranz L, Yoder E, Audeh W, Carter E, McNaughton L, Roussos J, Shivers S, Acs G, Cox C, MINT Investigators Group. Neoadjuvant chemotherapy for breast cancer: Nodal downstaging is highly correlated with pathological complete response [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD8-04.

Anti-C1 domain antibodies that accelerate factor VIII clearance contribute to antibody pathogenicity in a murine hemophilia A model

Essentials Inhibitor formation remains a challenging complication of hemophilia A care. The Bethesda assay is the primary method used for determining bleeding risk and management. Antibodies that block factor VIII binding to von Willebrand factor can increase FVIII clearance. Antibodies that increase clearance contribute to antibody pathogenicity.

SUMMARY

Background The development of neutralizing anti-factor VIII (FVIII) antibodies remains a challenging complication of modern hemophilia A care. In vitro assays are the primary method used for quantifying inhibitor titers, predicting bleeding risk, and determining bleeding management. However, other mechanisms of inhibition are not accounted for in these assays, which may result in discrepancies between the inhibitor titer and clinical bleeding symptoms. Objectives To evaluate FVIII clearance in vivo as a potential mechanism for antibody pathogenicity and to determine whether increased FVIII dosing regimens correct the associated bleeding phenotype. Methods FVIII-/- or FVIII-/- /von Willebrand factor (VWF)-/- mice were infused with anti-FVIII mAbs directed against the FVIII C1, C2 or A2 domains, followed by infusion of FVIII. Blood loss via the tail snip bleeding model, FVIII activity and FVIII antigen levels were subsequently measured. Results Pathogenic anti-C1 mAbs that compete with VWF for FVIII binding increased the clearance of FVIII-mAb complexes in FVIII-/- mice but not in FVIII-/- /VWF-/- mice. Additionally, pathogenic anti-C2 mAbs that inhibit FVIII binding to VWF increased FVIII clearance in FVIII-/- mice. Anti-C1, anti-C2 and anti-A2 mAbs that do not inhibit VWF binding did not accelerate FVIII clearance. Infusion of increased doses of FVIII in the presence of anti-C1 mAbs partially corrected blood loss in FVIII-/- mice. Conclusions A subset of antibodies that inhibit VWF binding to FVIII increase the clearance of FVIII-mAb complexes, which contributes to antibody pathogenicity. This may explain differences in the bleeding phenotype observed despite factor replacement in some patients with hemophilia A and low-titer inhibitors.

Sex-specific relevance of diabetes to occlusive vascular and other mortality: a collaborative meta-analysis of individual data from 980 793 adults from 68 prospective studies

BACKGROUND

Several studies have shown that diabetes confers a higher relative risk of vascular mortality among women than among men, but whether this increased relative risk in women exists across age groups and within defined levels of other risk factors is uncertain. We aimed to determine whether differences in established risk factors, such as blood pressure, BMI, smoking, and cholesterol, explain the higher relative risks of vascular mortality among women than among men.

METHODS

In our meta-analysis, we obtained individual participant-level data from studies included in the Prospective Studies Collaboration and the Asia Pacific Cohort Studies Collaboration that had obtained baseline information on age, sex, diabetes, total cholesterol, blood pressure, tobacco use, height, and weight. Data on causes of death were obtained from medical death certificates. We used Cox regression models to assess the relevance of diabetes (any type) to occlusive vascular mortality (ischaemic heart disease, ischaemic stroke, or other atherosclerotic deaths) by age, sex, and other major vascular risk factors, and to assess whether the associations of blood pressure, total cholesterol, and body-mass index (BMI) to occlusive vascular mortality are modified by diabetes.

RESULTS

Individual participant-level data were analysed from 980 793 adults. During 9·8 million person-years of follow-up, among participants aged between 35 and 89 years, 19 686 (25·6%) of 76 965 deaths were attributed to occlusive vascular disease. After controlling for major vascular risk factors, diabetes roughly doubled occlusive vascular mortality risk among men (death rate ratio [RR] 2·10, 95% CI 1·97-2·24) and tripled risk among women (3·00, 2·71-3·33; χ2 test for heterogeneity p<0·0001). For both sexes combined, the occlusive vascular death RRs were higher in younger individuals (aged 35-59 years: 2·60, 2·30-2·94) than in older individuals (aged 70-89 years: 2·01, 1·85-2·19; p=0·0001 for trend across age groups), and, across age groups, the death RRs were higher among women than among men. Therefore, women aged 35-59 years had the highest death RR across all age and sex groups (5·55, 4·15-7·44). However, since underlying confounder-adjusted occlusive vascular mortality rates at any age were higher in men than in women, the adjusted absolute excess occlusive vascular mortality associated with diabetes was similar for men and women. At ages 35-59 years, the excess absolute risk was 0·05% (95% CI 0·03-0·07) per year in women compared with 0·08% (0·05-0·10) per year in men; the corresponding excess at ages 70-89 years was 1·08% (0·84-1·32) per year in women and 0·91% (0·77-1·05) per year in men. Total cholesterol, blood pressure, and BMI each showed continuous log-linear associations with occlusive vascular mortality that were similar among individuals with and without diabetes across both sexes.

INTERPRETATION

Independent of other major vascular risk factors, diabetes substantially increased vascular risk in both men and women. Lifestyle changes to reduce smoking and obesity and use of cost-effective drugs that target major vascular risks (eg, statins and antihypertensive drugs) are important in both men and women with diabetes, but might not reduce the relative excess risk of occlusive vascular disease in women with diabetes, which remains unexplained.

FUNDING

UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union BIOMED programme, and National Institute on Aging (US National Institutes of Health).

The Importance of Dialysate Sodium Concentration in Determining Interdialytic Weight Gains in Chronic Hemodialysis Patients: The PanThames Renal Audit

Background and Objectives

There is controversy as to the optimum dialysate sodium to be used for hemodialysis patients, with reports of hypertension and increased interdialytic weight gains with high sodium dialysates and intradialytic hypotension and cramps with low sodium dialysates.

Methods

We analyzed the effect of different dialysate sodium concentrations during a one-week period in an audit of 2187 established patients regularly receiving dialysis three times a week. Patients were given general dietary advice to restrict dietary sodium intake, but no systematic assessment of dietary sodium intake was undertaken.

Results

The prescription of a dialysate sodium concentration of 140 mmol/L and >140 mmol/L, was associated with greater interdialytic weight gains, 3.5% and 4.1% respectively, compared to 2.8% and 2.7% for those using dialysate sodium concentrations of 137 and 136 mmol/L, respectively (p<0.05). The mean pulse pressure was greater patients dialyzing using a sodium of 140 mmol/L, compared to 136 mmol/L, 70 (13) vs 63 (15) mmHg (p<0.011). In addition, 13.5% of patients using the highest sodium dialysate suffered symptomatic intradialytic hypotension requiring intravenous fluid resuscitation, compared to 2.7% who used the lowest sodium concentrate (p<0.05).

Conclusions

This analysis would support the use of lower dialysate sodium concentrations to aid in reducing interdialytic weight gains and subsequent intradialytic hypotension.

Fall frequency and associated factors among men and women with or at risk for HIV infection

OBJECTIVES

Falls and fall-related injuries are a major public health concern. HIV-infected adults have been shown to have a high incidence of falls. Identification of major risk factors for falls that are unique to HIV infection or similar to those in the general population will inform development of future interventions for fall prevention.

METHODS

HIV-infected and uninfected men and women participating in the Hearing and Balance Substudy of the Multicenter AIDS Cohort Study and Women's Interagency HIV Study were asked about balance symptoms and falls during the prior 12 months. Falls were categorized as 0, 1, or ≥ 2; proportional odds logistic regression models were used to investigate relationships between falls and demographic and clinical variables and multivariable models were created.

RESULTS

Twenty-four per cent of 303 HIV-infected participants reported at least one fall compared with 18% of 233 HIV-uninfected participants (P = 0.27). HIV-infected participants were demographically different from HIV-uninfected participants, and were more likely to report clinical imbalance symptoms (P ≤ 0.035). In univariate analyses, more falls were associated with hepatitis C, female sex, obesity, smoking, and clinical imbalance symptoms, but not age, HIV serostatus or other comorbidities. In multivariable analyses, female sex and imbalance symptoms were independently associated with more falls. Among HIV-infected participants, smoking, a higher number of medications, and imbalance symptoms remained independent fall predictors, while current protease inhibitor use was protective.

CONCLUSIONS

Similar rates of falls among HIV-infected and uninfected participants were largely explained by a high prevalence of imbalance symptoms. Routine assessment of falls and dizziness/imbalance symptoms should be considered, with interventions targeted at reducing symptomatology.

Neither Intraocular Grafts of Retinal Cell Homogenates Nor Live Non-Retinal Neurons Produce Behavioral Recovery in Rats with Light-Damaged Retinas

Previously we have observed that fetal retinal cells grafted to the subretinal space of blind rats produced a functional recovery as determined by testing the visual inhibition of the startle response. Following those studies, we performed experiments to test whether the injection itself, cell by-products, or unrelated neural cells could also produce an effect. Visual function was tested by examining the inhibitory effect of a brief light flash (300 Ix) on the acoustic startle response to an immediately following intense noise burst in light blinded Fischer 344 rats. Animals were tested before and after grafts of fetal retinal cell homogenates, dissociated perinatal cerebellar cells, and sham injections in the subretinal space. Behavioral testing continued every 2 wk for 14 wk after the graft. In the pretests, the light flash inhibited the startle response, maximal at intervals of 40-70 ms with recovery thereafter. In contrast, after exposure for 4 wk to fluorescent light (300 lx) and a rest in a normal 12/12 h light/ dark environment the rats showed reflex facilitation to the light, maximal at an interval of 110 ms, followed by a late period of reflex inhibition. The light flash had no effect on other rats that had been blinded by bilateral enucleation. Light blinded animals receiving either cerebellar grafts or retinal cell homogenates were no different in performance from their sham injected control animals. The present data suggest that neither subretinal injections of neural cells nor nonspecific neurochemical factors are able to elicit a positive behavioral response in visually impaired animals.

Storage of Human Fetal Retina in Optisol Prior to Subretinal Transplantation

We have previously reported that Optisol, a commercially available medium (Chiron Vision, Irvine, CA), is a favorable fluid for the storage of neural retina. We now characterize the cell survival and histologic integrity of the tissue following storage and then transplantation. Neural retinas from human fetal eyes obtained within 1 h of pregnancy termination were stored in Optisol-GS medium (containing TC-199 and MEM medium, 2.5% chondroitin sulfate, 1% dextran, HEPES buffer, gentamicin sulfate, 0.1 mmol/L nonessential amino acids, sodium bicarbonate, 1 mmol/L sodium pyruvate, and additional antioxidants), at 4°C for the following time periods: 0, 1, 2, and 7 days, and then tested for viability. Retinas stored for 2 and 7 days were mechanically dissociated and grafted into the eyes of light-damaged Fischer 344 rats (17 animals, 28 eyes). Non-transplanted eyes received injections of vehicle only (5 animals, 6 eyes). All animals were immunosuppressed daily with cyclosporine (10 mg/kg). All experiments were conducted in strict accordance with institutional, federal, and ARVO guidelines. Cell viability averaged 94.8%, 90.2%, 83.2%, and 76.8% at 0, 1, 2, and 7 days storage, respectively. Light microscopy demonstrated that the fetal retina was preserved without evident changes for up to 48 h. Up to 7 days there was a good to very good preservation of the cells in the outer neuroblastic layer. One month after transplantation subretinal grafts of retinal tissue stored for 2 and 7 days in Optisol showed good integration with host retina and initial photoreceptor differentiation. Optisol is a widely used medium for the preservation of human corneas prior to transplantation. Our results show that this medium is also highly suitable for preserving human fetal retinas prior to transplantation.

Hearing Loss and Quality of Life (QOL) among Human Immunodeficiency Virus (HIV)-Infected and Uninfected Adults

OBJECTIVE

Research has established that human immunodeficiency virus (HIV) causes hearing loss. Studies have yet to evaluate the impact on quality of life (QOL). This project evaluates the effect of hearing loss on QOL by HIV status.

METHODS

The study participants were from the Multicenter AIDS Cohort Study (MACS) and the Women's Interagency HIV study (WIHS). A total of 248 men and 127 women participated. Pure-tone air conduction thresholds were collected for each ear at frequencies from 250 through 8000 Hz. Pure-tone averages (PTAs) for each ear were calculated as the mean of air conduction thresholds in low frequencies (i.e., 250, 500, 1000 and 2000 Hz) and high frequencies (i.e., 3000, 4000, 6000 and 8000 Hz). QOL data were gathered with the Short Form 36 Health Survey and Medical Outcome Study (MOS)-HIV instrument in the MACS and WIHS, respectively. A median regression analysis was performed to test the association of PTAs with QOL by HIV status.

RESULTS

There was no significant association between hearing loss and QOL scores at low and high pure tone averages in HIV positive and negative individuals. HIV status, HIV biomarkers and treatment did not change the lack of association of low and high pure tone averages with poorer QOL.

CONCLUSION

Although we did not find a statistically significant association of hearing loss with QOL by HIV status, testing for hearing loss with aging and recommending treatment may offset any presumed later life decline in QOL.

Mycoplasma hominis and Gardnerella vaginalis display a significant synergistic relationship in bacterial vaginosis

Gardnerella vaginalis plays an important role in bacterial vaginosis (BV,) while the role of genital Mollicutes is less obvious. The diagnosis of BV by use of the current Gram stain Nugent score is also suboptimal for defining the role of Mollicutes that lack a cell wall. Since bacterial load and diversity is an important prerequisite for BV, real-time quantitative polymerase chain reaction (qPCR) assays enable these to be assessed. The purpose of this study was to define the role of genital Mollicutes and potential patterns of synergy with G. vaginalis in women with BV. Vaginal swabs from 130 women categorised by Nugent score as BV (n = 28), intermediate (n = 22) and non-BV (n = 80) were tested against four qPCR TaqMan assays targeting G. vaginalis, Mycoplasma hominis, M. genitalium, Ureaplasma urealyticum and U. parvum. Statistical analyses were used to compare bacterial prevalence and load between the three groups of women. Mycoplasma hominis and G. vaginalis co-infection was significantly more common in BV (60.7 %) compared to intermediate (36.4 %) and non-BV (8.8 %) Nugent scores (p < 0.001). Significantly higher loads of M. hominis (p = 0.001) and G. vaginalis (p < 0.001) were detected in women with BV and the respective loads in M. hominis and G. vaginalis co-infections displayed a significant positive correlation (p < 0.001; r = 0.60). No significant associations were seen with the other Mollicutes. The findings strengthen the evidence of a role for M. hominis in BV and a potential synergy with G. vaginalis. This synergy could be an important trigger of the condition and sexual contact the conduit for the transmission of an otherwise commensal bacterium that could initiate it.

Evaluation of caffeine and the development of necrotizing enterocolitis

OBJECTIVE

To test the association between medical or surgical necrotizing enterocolitis (NEC) and caffeine administration in premature infants.

STUDY DESIGN

This single-center, retrospective study evaluated patients admitted to a level 3 neonatal intensive care unit (NICU) over an 18-month period. All patients were evaluated for factors associated with the development of NEC including exposure to caffeine (dosing and duration), gestational age, birth weight, vasoactive medications and maternal illicit drug use.

RESULTS

There were 615 subjects included in the study; among these subjects, 7.3% (n = 45) developed NEC (35 subjects receiving caffeine and 10 subjects not receiving caffeine). The administration of caffeine (p = 0.008), birth weight (p = 0.014) and the use of vasopressors (p = 0.033) were associated with the development of NEC. When considering only infants with a birth weight less than 1500 g and less than 32 weeks gestation, the effects of caffeine and vasopressor use remained statistically significant (p = 0.047 and p = 0.045, respectively). The time to development of NEC did not differ statistically between patients receiving caffeine and those not receiving caffeine (p = 0.129).

CONCLUSION

A potential association between the administration of caffeine and the development of medical or surgical necrotizing enterocolitis in premature infants exists. Further investigation of dose-dependent effects and loading doses is warranted.

Species-specific responses of N homeostasis and electrolyte handling to low N intake: a comparative physiological approach in a monogastric and a ruminant species

In our former studies low crude protein (LCP) intake influenced N homeostasis and electrolyte handling in goats. We hypothesised that due to rumino-hepatic nitrogen (N) recycling adaptation of N homeostasis and adjustment of electrolyte handling to LCP intake differs between goats and monogastric animals. Therefore, an experiment similar to that with goats was conducted with rats. Two feeding groups received a diet either containing 20 or 8 % crude protein (as fed basis) for 5 weeks and intake and excretion of N, calcium (Ca) and phosphorus (P) were determined. To detect systemic and endocrine adaptation to LCP intake plasma concentrations of urea, Ca, phosphate (Pi), insulin-like growth factor 1 (IGF-1), 1,25-dihydroxyvitamin D3 (calcitriol), parathyroid hormone (PTH) and cross-linked telopeptide of type I collagen (CTX) were measured. Adjustment of renal electrolyte transport was assessed by detecting protein expression of key proteins of renal Pi transport. All data were compared with the data of the goat experiment. LCP intake decreased plasma urea concentration stronger in goats than in rats. In both species urinary N excretion declined, but faecal N excretion decreased in goats only. Furthermore, in goats urinary Ca excretion decreased, but in rats urinary Ca concentration increased. Decreased plasma IGF-1 and calcitriol concentrations were found in goats only. Thus, renal Ca excretion appears to be a common target in adaptation of electrolyte homeostasis in both species, but is regulated differently.

HIBAG--HLA genotype imputation with attribute bagging

Genotyping of classical human leukocyte antigen (HLA) alleles is an essential tool in the analysis of diseases and adverse drug reactions with associations mapping to the major histocompatibility complex (MHC). However, deriving high-resolution HLA types subsequent to whole-genome single-nucleotide polymorphism (SNP) typing or sequencing is often cost prohibitive for large samples. An alternative approach takes advantage of the extended haplotype structure within the MHC to predict HLA alleles using dense SNP genotypes, such as those available from genome-wide SNP panels. Current methods for HLA imputation are difficult to apply or may require the user to have access to large training data sets with SNP and HLA types. We propose HIBAG, HLA Imputation using attribute BAGging, that makes predictions by averaging HLA-type posterior probabilities over an ensemble of classifiers built on bootstrap samples. We assess the performance of HIBAG using our study data (n=2668 subjects of European ancestry) as a training set and HLA data from the British 1958 birth cohort study (n≈1000 subjects) as independent validation samples. Prediction accuracies for HLA-A, B, C, DRB1 and DQB1 range from 92.2% to 98.1% using a set of SNP markers common to the Illumina 1M Duo, OmniQuad, OmniExpress, 660K and 550K platforms. HIBAG performed well compared with the other two leading methods, HLA*IMP and BEAGLE. This method is implemented in a freely available HIBAG R package that includes pre-fit classifiers for European, Asian, Hispanic and African ancestries, providing a readily available imputation approach without the need to have access to large training data sets.

What is the burden of axillary disease after neoadjuvant therapy in women with locally advanced breast cancer?

BACKGROUND

The burden of axillary disease in patients with locally advanced breast cancer (labc) after neoadjuvant therapy (nat) has not been extensively described in a large modern cohort. Here, we describe the extent of nodal metastases after nat in patients with labc.

METHODS

All patients with labc treated at a single institution during 2002-2007 were identified. Demographic, radiologic, and pathologic variables were extracted. To assess the extent of lymph node metastases after nat, patients were separated into two groups: those with and without clinical or radiologic evidence of lymph node metastases before nat. Axillary lymph nodes retrieved at surgery that had no evidence of metastases after hematoxylin and eosin (h&e) staining underwent further pathology evaluation.

RESULTS

Of the 116 patients identified, 115 were female (median age: 48.5). Before nat, 26 patients were clinically and radiologically node-negative; of those 26, 14 were histologically negative on final pathology. After serial sectioning and immunohistochemistry, 9 of 26 (35%) were node-negative. Of the 90 patients who had clinical or radiologic evidence of lymph node metastases before nat, 23 (26%) had no evidence of lymph node metastases on h&e staining. After serial sectioning and immunohistochemistry, 19 (21%) had no further axillary lymph node metastases. Overall, 76% of patients had pathology evidence of lymph node metastases after nat.

CONCLUSIONS

Most patients with labc have axillary metastases after nat. Our findings support axillary lymph node dissection and locoregional radiation in most patients with labc after nat.

Abstract OT3-4-02: MINT I: Multi-Institutional Neo-adjuvant Therapy, MammaPrint Project I

Background: Women with locally advanced breast cancer (LABC) are often treated with neo-adjuvant chemotherapy to reduce the size of the tumor prior to surgery, to enable breast conserving surgery and to observe the clinical effect of therapy in real time. Studies have shown that the 25–27% of individuals who have a pathologic complete response (pCR) to neoadjuvant therapy have a survival advantage of 80% in 5 years, which is double the expected survival of the remaining patients without pCR. If patients who are likely to show a pCR could be identified prior to initiation of therapy, it would enable more informed treatment decisions – patients likely to respond would be served well by current neoadjuvant chemotherapy protocols, while those unlikely to respond may be better suited to innovative new strategies for drug discovery [von Minckwitz et al. JCO 2006]. Genomics assays, which are widely used to provide prognostic and predictive information in early breast cancer, have the potential to provide information on the likelihood of a patient with LABC responding to neo-adjuvant therapy [Glück et al. ASCO 2012].

Trial design: MINT I is a prospective study designed to test the ability of molecular profiling, as well as traditional pathologic and clinical prognostic factors, to predict responsiveness to neo-adjuvant chemotherapy in patients with LABC. MammaPrint risk profile, BluePrint molecular subtyping profile, TargetPrint estrogen receptor (ER), progesterone receptor (PR) and HER2 single gene readout, and the 56-gene TheraPrint Research Gene Panel will be analyzed on a fresh tumor specimen using the whole genome array. Patients will receive neo-adjuvant chemotherapy pre-specified in the protocol. Response will be measured centrally. pCR is defined as the absence of invasive carcinoma in both the breast and axilla at microscopic examination of the resection specimen, regardless of the presence of carcinoma in situ.

Eligibility: The study will include women ≥18 years with histologically-proven invasive breast cancer T2 (≥3.5cm)-T4, N0M0 or T2-T4N1M0, adequate bone marrow reserves and normal renal and hepatic function who signed an IRB approved informed consent.

Objectives: The objectives of the study are to: 1. Determine the predictive power of MammaPrint and BluePrint for sensitivity to neo-adjuvant chemotherapy as measured by pCR.2. Compare TargetPrint ER, PR and HER2 with local and centralized IHC and/or CISH/FISH assessment.3. Identify correlations between TheraPrint and response to neo-adjuvant chemotherapy.4. Identify and/or validate predictive gene expression profiles of clinical response or resistance to neo-adjuvant chemotherapy.5. Compare BluePrint with IHC-based subtype classification.

Statistical methods: Standard statistical tests such as the Pearson Chi-square test will be used to characterize and evaluate the relationship between chemoresponsiveness and gene expression patterns.

Accrual: A total of 226 eligible patients will be enrolled from multiple institutions. To date (June 06, 2012), 31 patients have been enrolled.

Clinical trial registry number: NCT01501487.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr OT3-4-02.