Public Health Dashboards in Overdose Prevention: The Rhode Island Approach to Public Health Data Literacy, Partnerships, and Action

As the field of public health rises to the demands of real-time surveillance and rapid data-sharing needs in a postpandemic world, it is time to examine our approaches to the dissemination and accessibility of such data. Distinct challenges exist when working to develop a shared public health language and narratives based on data. It requires that we assess our understanding of public health data literacy, revisit our approach to communication and engagement, and continuously evaluate our impact and relevance. Key stakeholders and cocreators are critical to this process and include people with lived experience, community organizations, governmental partners, and research institutions. In this viewpoint paper, we offer an instructive approach to the tools we used, assessed, and adapted across 3 unique overdose data dashboard projects in Rhode Island, United States. We are calling this model the "Rhode Island Approach to Public Health Data Literacy, Partnerships, and Action." This approach reflects the iterative lessons learned about the improvement of data dashboards through collaboration and strong partnerships across community members, state agencies, and an academic research team. We will highlight key tools and approaches that are accessible and engaging and allow developers and stakeholders to self-assess their goals for their data dashboards and evaluate engagement with these tools by their desired audiences and users.

Comparing Projected Fatal Overdose Outcomes and Costs of Strategies to Expand Community-Based Distribution of Naloxone in Rhode Island

IMPORTANCE

In 2021, the state of Rhode Island distributed 10 000 additional naloxone kits compared with the prior year through partnerships with community-based organizations.

OBJECTIVE

To compare various strategies to increase naloxone distribution through community-based programs in Rhode Island to identify one most effective and efficient strategy in preventing opioid overdose deaths (OODs).

DESIGN, SETTING, AND PARTICIPANTS

In this decision analytical model study conducted from January 2016 to December 2022, a spatial microsimulation model with an integrated decision tree was developed and calibrated to compare the outcomes of alternative strategies for distributing 10 000 additional naloxone kits annually among all individuals at risk for opioid overdose in Rhode Island.

INTERVENTIONS

Distribution of 10 000 additional naloxone kits annually, focusing on people who inject drugs, people who use illicit opioids and stimulants, individuals at various levels of risk for opioid overdose, or people who misuse prescription opioids vs no additional kits (status quo). Two expanded distribution implementation approaches were considered: one consistent with the current spatial distribution patterns for each distribution program type (supply-based approach) and one consistent with the current spatial distribution of individuals in each of the risk groups, assuming that programs could direct the additional kits to new geographic areas if required (demand-based approach).

MAIN OUTCOMES AND MEASURES

Witnessed OODs, cost per OOD averted (efficiency), geospatial health inequality measured by the Theil index, and between-group variance for OOD rates.

RESULTS

A total of 63 131 simulated individuals were estimated to be at risk for opioid overdose in Rhode Island based on current population data. With the supply-based approach, prioritizing additional naloxone kits to people who use illicit drugs averted more witnessed OODs by an estimated mean of 18.9% (95% simulation interval [SI], 13.1%-30.7%) annually. Expanded naloxone distribution using the demand-based approach and focusing on people who inject drugs had the best outcomes across all scenarios, averting an estimated mean of 25.3% (95% SI, 13.1%-37.6%) of witnessed OODs annually, at the lowest mean incremental cost of $27 312 per OOD averted. Other strategies were associated with fewer OODs averted at higher costs but showed similar patterns of improved outcomes and lower unit costs if kits could be reallocated to areas with greater need. The demand-based approach reduced geospatial inequality in OOD rates in all scenarios compared with the supply-based approach and status quo.

CONCLUSIONS AND RELEVANCE

In this decision analytical model study, variations in the effectiveness, efficiency, and health inequality of the different naloxone distribution expansion strategies and approaches were identified. Future efforts should be prioritized for people at highest risk for overdose (those who inject drugs or use illicit drugs) and redirected toward areas with the greatest need. These findings may inform future naloxone distribution priority settings.

Preventing Overdose Using Information and Data from the Environment (PROVIDENT): protocol for a randomized, population-based, community intervention trial

BACKGROUND AND AIMS

In light of the accelerating drug overdose epidemic in North America, new strategies are needed to identify communities most at risk to prioritize geographically the existing public health resources (e.g. street outreach, naloxone distribution efforts). We aimed to develop PROVIDENT (Preventing Overdose using Information and Data from the Environment), a machine learning-based forecasting tool to predict future overdose deaths at the census block group (i.e. neighbourhood) level.

DESIGN

Randomized, population-based, community intervention trial.

SETTING

Rhode Island, USA.

PARTICIPANTS

All people who reside in Rhode Island during the study period may contribute data to either the model or the trial outcomes.

INTERVENTION

Each of the state's 39 municipalities will be randomized to the intervention (PROVIDENT) or comparator condition. An interactive, web-based tool will be developed to visualize the PROVIDENT model predictions. Municipalities assigned to the treatment arm will receive neighbourhood risk predictions from the PROVIDENT model, and state agencies and community-based organizations will direct resources to neighbourhoods identified as high risk. Municipalities assigned to the control arm will continue to receive surveillance information and overdose prevention resources, but they will not receive neighbourhood risk predictions.

MEASUREMENTS

The primary outcome is the municipal-level rate of fatal and non-fatal drug overdoses. Fatal overdoses will be defined as unintentional drug-related death; non-fatal overdoses will be defined as an emergency department visit for a suspected overdose reported through the state's syndromic surveillance system. Intervention efficacy will be assessed using Poisson or negative binomial regression to estimate incidence rate ratios comparing fatal and non-fatal overdose rates in treatment vs. control municipalities.

COMMENTS

The findings will inform the utility of predictive modelling as a tool to improve public health decision-making and inform resource allocation to communities that should be prioritized for prevention, treatment, recovery and overdose rescue services.

Identifying Predictors of Opioid Overdose Death at a Neighborhood Level With Machine Learning

Predictors of opioid overdose death in neighborhoods are important to identify, both to understand characteristics of high-risk areas and to prioritize limited prevention and intervention resources. Machine learning methods could serve as a valuable tool for identifying neighborhood-level predictors. We examined statewide data on opioid overdose death from Rhode Island (log-transformed rates for 2016-2019) and 203 covariates from the American Community Survey for 742 US Census block groups. The analysis included a least absolute shrinkage and selection operator (LASSO) algorithm followed by variable importance rankings from a random forest algorithm. We employed double cross-validation, with 10 folds in the inner loop to train the model and 4 outer folds to assess predictive performance. The ranked variables included a range of dimensions of socioeconomic status, including education, income and wealth, residential stability, race/ethnicity, social isolation, and occupational status. The R2 value of the model on testing data was 0.17. While many predictors of overdose death were in established domains (education, income, occupation), we also identified novel domains (residential stability, racial/ethnic distribution, and social isolation). Predictive modeling with machine learning can identify new neighborhood-level predictors of overdose in the continually evolving opioid epidemic and anticipate the neighborhoods at high risk of overdose mortality.

Targeting community-based naloxone distribution using opioid overdose death rates: A descriptive analysis of naloxone rescue kits and opioid overdose deaths in Massachusetts and Rhode Island

BACKGROUND

Rates of fatal opioid overdose in Massachusetts (MA) and Rhode Island (RI) far exceed the national average. Community-based opioid education and naloxone distribution (OEND) programs are effective public health interventions to prevent overdose deaths. We compared naloxone distribution and opioid overdose death rates in MA and RI to identify priority communities for expanded OEND.

METHODS

We compared spatial patterns of opioid overdose fatalities and naloxone distribution through OEND programs in MA and RI during 2016 to 2019 using public health department data. The county-level ratio of naloxone kits distributed through OEND programs per opioid overdose death was estimated and mapped to identify potential gaps in naloxone availability across geographic regions and over time.

RESULTS

From 2016 to 2019, the statewide community-based naloxone distribution to opioid overdose death ratio improved in both states, although more rapidly in RI (from 11.8 in 2016 to 35.6 in 2019) than in MA (from 12.3 to 17.2), driven primarily by elevated and increasing rates of naloxone distribution in RI. We identified some urban/non-urban differences, with higher naloxone distribution relative to opioid overdose deaths in more urban counties, and we observed some counties with high rates of overdose deaths but low rates of naloxone kits distributed through OEND programs.

CONCLUSIONS

We identified variations in spatial patterns of opioid overdose fatalities and naloxone availability, and these disparities appeared to be widening in some areas over time. Data on the spatial distribution of naloxone distribution and opioid overdose deaths can inform targeted, community-based naloxone distribution strategies that optimize resources to prevent opioid overdose fatalities.

Machine learning takes a village: Assessing neighbourhood-level vulnerability for an overdose and infectious disease outbreak

BACKGROUND

Multiple areas in the United States of America (USA) are experiencing high rates of overdose and outbreaks of bloodborne infections, including HIV and hepatitis C virus (HCV), due to non-sterile injection drug use. We aimed to identify neighbourhoods at increased vulnerability for overdose and infectious disease outbreaks in Rhode Island, USA. The primary aim was to pilot machine learning methods to identify which neighbourhood-level factors were important for creating "vulnerability assessment scores" across the state. The secondary aim was to engage stakeholders to pilot an interactive mapping tool and visualize the results.

METHODS

From September 2018 to November 2019, we conducted a neighbourhood-level vulnerability assessment and stakeholder engagement process named The VILLAGE Project (Vulnerability Investigation of underlying Local risk And Geographic Events). We developed a predictive analytics model using machine learning methods (LASSO, Elastic Net, and RIDGE) to identify areas with increased vulnerability to an outbreak of overdose, HIV and HCV, using census tract-level counts of overdose deaths as a proxy for injection drug use patterns and related health outcomes. Stakeholders reviewed mapping tools for face validity and community distribution.

RESULTS

Machine learning prediction models were suitable for estimating relative neighbourhood-level vulnerability to an outbreak. Variables of importance in the model included housing cost burden, prior overdose deaths, housing density, and education level. Eighty-nine census tracts (37%) with no prior overdose fatalities were identified as being vulnerable to such an outbreak, and nine of those were identified as having a vulnerability assessment score in the top 25%. Results were disseminated as a vulnerability stratification map and an online interactive mapping tool.

CONCLUSION

Machine learning methods are well suited to predict neighborhoods at higher vulnerability to an outbreak. These methods show promise as a tool to assess structural vulnerabilities and work to prevent outbreaks at the local level.

US drug overdose mortality: 2009-2018 increases affect young people who use drugs

PURPOSE

Drug overdose mortality remains a public health concern in many countries globally. In the US, overdoses involving synthetic opioids are the primary contributor to overdose mortality. We aimed to assess trends in overdose death due to synthetic opioids among young people and describe key demographic and temporal changes.

METHODS

Data from the US National Vital Statistics System Multiple Cause of Death files for 2009-2018 were analysed to determine age-specific overdose death rates by region (i.e. east versus west of the Mississippi River). Age-adjusted overdose mortality rates were used to compare demographic differences in all drug and synthetic opioid overdose among young people (aged 15-34 years) using a joinpoint regression with Poisson-approximated standard errors.

RESULTS

Driven by synthetic opioid overdose, the age burden of mortality shifted towards young people in eastern states and remained approximately constant in western states over the study period. The highest increases in drug overdose mortality rates were observed in young Black and Hispanic people and those living in large metropolitan areas.

CONCLUSIONS

Rapid changes in the demographics of overdose demonstrate distinct but overlapping US overdose sub-epidemics, and highlight the need for targeted interventions to reduce overdose risk in young people.

Analysis of Pharmaceutical Industry Marketing of Stimulants, 2014 Through 2018

This study examines the number and dollar amount of payments to physicians from companies marketing prescription stimulant medications.

Defining a recovery-oriented cascade of care for opioid use disorder: A community-driven, statewide cross-sectional assessment

BACKGROUND

In light of the accelerating and rapidly evolving overdose crisis in the United States (US), new strategies are needed to address the epidemic and to efficiently engage and retain individuals in care for opioid use disorder (OUD). Moreover, there is an increasing need for novel approaches to using health data to identify gaps in the cascade of care for persons with OUD.

METHODS AND FINDINGS

Between June 2018 and May 2019, we engaged a diverse stakeholder group (including directors of statewide health and social service agencies) to develop a statewide, patient-centered cascade of care for OUD for Rhode Island, a small state in New England, a region highly impacted by the opioid crisis. Through an iterative process, we modified the cascade of care defined by Williams et al. for use in Rhode Island using key national survey data and statewide health claims datasets to create a cross-sectional summary of 5 stages in the cascade. Approximately 47,000 Rhode Islanders (5.2%) were estimated to be at risk for OUD (stage 0) in 2016. At the same time, 26,000 Rhode Islanders had a medical claim related to an OUD diagnosis, accounting for 55% of the population at risk (stage 1); 27% of the stage 0 population, 12,700 people, showed evidence of initiation of medication for OUD (MOUD, stage 2), and 18%, or 8,300 people, had evidence of retention on MOUD (stage 3). Imputation from a national survey estimated that 4,200 Rhode Islanders were in recovery from OUD as of 2016, representing 9% of the total population at risk. Limitations included use of self-report data to arrive at estimates of the number of individuals at risk for OUD and using a national estimate to identify the number of individuals in recovery due to a lack of available state data sources.

CONCLUSIONS

Our findings indicate that cross-sectional summaries of the cascade of care for OUD can be used as a health policy tool to identify gaps in care, inform data-driven policy decisions, set benchmarks for quality, and improve health outcomes for persons with OUD. There exists a significant opportunity to increase engagement prior to the initiation of OUD treatment (i.e., identification of OUD symptoms via routine screening or acute presentation) and improve retention and remission from OUD symptoms through improved community-supported processes of recovery. To do this more precisely, states should work to systematically collect data to populate their own cascade of care as a health policy tool to enhance system-level interventions and maximize engagement in care.

Suspected involvement of fentanyl in prior overdoses and engagement in harm reduction practices among young adults who use drugs

Background: From 2011 to 2016, the United States has experienced a 55% increase in overall overdose deaths and a 260% increase in fatal fentanyl-related overdoses. Increasing engagement in harm reduction practices is essential to reducing the rate of fentanyl-related overdoses. This study sought to examine the uptake of harm reduction practices among young adults who reported recent drug use and who were recruited for a study to assess the utility and acceptability of rapid fentanyl test strips. Methods: Between May and October 2017, 93 young adults who reported drug use in the past 30 days were recruited through word of mouth, Internet advertising, and public canvasing. Participants completed an interviewer-administered survey that assessed participants' sociodemographic and behavioral characteristics, suspected fentanyl exposure, and overdose history. We assessed harm reduction practices and other correlates associated with experiencing a suspected fentanyl-related overdose. Results: Of 93 eligible participants, 36% (n = 34) reported ever having experienced an overdose, among whom 53% (n = 18) suspected having experienced a fentanyl-related overdose. Participants who had ever experienced a fentanyl-related overdose were more likely to keep naloxone nearby when using drugs compared with those who had never experienced an overdose and those who had experienced an overdose that they did not suspect was related to fentanyl (P < .001). Additionally, experiencing a suspected fentanyl-related overdose was associated with having previously administered naloxone to someone else experiencing an overdose (P < .001). Conclusion: Those who had experienced a suspected fentanyl-related overdose were more likely to carry and administer naloxone. Future overdose prevention interventions should involve persons who have experienced a suspected fentanyl overdose and/or responded to an overdose in order to develop harm reduction programs that meet the needs of those at risk of an overdose.

Perspectives on rapid fentanyl test strips as a harm reduction practice among young adults who use drugs: a qualitative study

BACKGROUND

In 2016, drug overdose deaths exceeded 64,000 in the United States, driven by a sixfold increase in deaths attributable to illicitly manufactured fentanyl. Rapid fentanyl test strips (FTS), used to detect fentanyl in illicit drugs, may help inform people who use drugs about their risk of fentanyl exposure prior to consumption. This qualitative study assessed perceptions of FTS among young adults.

METHODS

From May to September 2017, we recruited a convenience sample of 93 young adults in Rhode Island (age 18-35 years) with self-reported drug use in the past 30 days to participate in a pilot study aimed at better understanding perspectives of using take-home FTS for personal use. Participants completed a baseline quantitative survey, then completed a training to learn how to use the FTS. Participants then received ten FTS for personal use and were asked to return 2-4 weeks later to complete a brief quantitative and structured qualitative interview. Interviews were transcribed, coded, and double coded in NVivo (Version 11).

RESULTS

Of the 81 (87%) participants who returned for follow-up, the majority (n = 62, 77%) used at least one FTS, and of those, a majority found them to be useful and straightforward to use. Positive FTS results led some participants to alter their drug use behaviors, including discarding their drug supply, using with someone else, and keeping naloxone nearby. Participants also reported giving FTS to friends who they felt were at high risk for fentanyl exposure.

CONCLUSION

These findings provide important perspectives on the use of FTS among young adults who use drugs. Given the high level of acceptability and behavioral changes reported by study participants, FTS may be a useful harm reduction intervention to reduce fentanyl overdose risk among this population.

TRIAL REGISTRATION

The study protocol is registered with the US National Library of Medicine, Identifier NCT03373825, 12/24/2017, registered retrospectively. https://clinicaltrials.gov/ct2/show/NCT03373825?id=NCT03373825&rank=1.

Use of rapid fentanyl test strips among young adults who use drugs

BACKGROUND

The overdose epidemic has been exacerbated by a dramatic increase in deaths involving illicitly manufactured fentanyl (IMF). Drug checking is a novel strategy to identify IMF in illicit drugs. We examined the uptake and acceptability of rapid fentanyl test strips among young adults.

METHODS

From May to September 2017, we recruited 93 young adults in Rhode Island who reported injecting drugs or using heroin, cocaine, or illicitly obtained prescription pills in the past 30 days. Participants were asked to test either their urine after drug use (post-consumption) or a drug sample prior to use (pre-consumption) using rapid fentanyl test strips. After a questionnaire and a brief training, participants received ten strips for their personal use and were asked to return for a one-month follow-up visit, which assessed the uptake and acceptability of the rapid strips tests and the behavioral outcomes associated with receipt of a positive test.

RESULTS

Of the 81 (87%) participants who returned for follow-up and who had complete data, the mean age was 27, 45 (56%) were male, and 37 (46%) were non-white. A total of 62 participants (77%) reported using at least one test strip. Of these, 31 (50%) received at least one positive result. A positive result was associated with older age, homelessness, heroin use, injection drug use, ever witnessing an overdose, and concern about overdose or drugs being laced with fentanyl (all p < 0.05). Receiving a positive result was significantly associated with reporting a positive change in overdose risk behavior between baseline and follow-up (p ≤  0.01). Among all participants, 79 (98%) reported confidence in their ability to use the test strips and 77 (95%) wanted to use them in the future.

CONCLUSIONS

Young adults reported high uptake and acceptability of fentanyl test strips to detect IMF in illicit drugs.

Portable Pocket colposcopy performs comparably to standard-of-care clinical colposcopy using acetic acid and Lugol's iodine as contrast mediators: an investigational study in Peru

OBJECTIVE

Our goal was to develop a tele-colposcopy platform for primary-care clinics to improve screening sensitivity and access. Specifically, we developed a low-cost, portable Pocket colposcope and evaluated its performance in a tertiary healthcare centre in Peru.

DESIGN AND SETTING

Images of the cervix were captured with a standard-of-care and Pocket colposcope at la Liga Contra el Cáncer in Lima, Peru.

POPULATION

Two hundred Peruvian women with abnormal cytology and/or human papillomavirus positivity were enrolled.

METHODS

Images were collected using acetic acid and Lugol's iodine as contrast agents. Biopsies were taken as per standard-of-care procedures.

MAIN OUTCOME MEASURES

After passing quality review, images from 129 women were sent to four physicians who provided a diagnosis for each image.

RESULTS

Physician interpretation of images from the two colposcopes agreed 83.1% of the time. The average sensitivity and specificity of physician interpretation compared with pathology was similar for the Pocket (sensitivity = 71.2%, specificity = 57.5%) and standard-of-care (sensitivity = 79.8%, specificity = 56.6%) colposcopes. When compared with a previous study where only acetic acid was applied to the cervix, results indicated that adding Lugol's iodine as a secondary contrast agent improved the percent agreement between colposcopes for all pathological categories by up to 8.9% and the sensitivity and specificity of physician interpretation compared with pathology by over 6.0 and 9.0%, respectively.

CONCLUSIONS

The Pocket colposcope performance was similar to that of a standard-of-care colposcope when used to identify precancerous and cancerous lesions using acetic acid and Lugol's iodine during colposcopy examinations in Peru.

TWEETABLE ABSTRACT

The Pocket colposcope performance was similar to that of a standard-of-care colposcope when identifying cervical lesions.

Association of Pharmaceutical Industry Marketing of Opioid Products to Physicians With Subsequent Opioid Prescribing

This database analysis examines the extent to which pharmaceutical industry marketing of opioid products to physicians during 2014 was associated with opioid prescribing during 2015.

High willingness to use rapid fentanyl test strips among young adults who use drugs

BACKGROUND

Synthetic opioid overdose mortality among young adults has risen more than 300% in the USA since 2013, primarily due to the contamination of heroin and other drugs with illicitly manufactured fentanyl. Rapid test strips, which can be used to detect the presence of fentanyl in drug samples (before use) or urine (after use), may help inform people about their exposure risk. The purpose of this study was to determine whether young adults who use drugs were willing to use rapid test strips as a harm reduction intervention to prevent overdose. We hypothesized that those who had ever overdosed would be more willing to use the test strips.

METHODS

We recruited a convenience sample of young adults who use drugs in Rhode Island from May to September 2017. Eligible participants (aged 18 to 35 with past 30-day drug use) completed an interviewer-administered survey. The survey assessed participant's socio-demographic and behavioral characteristics, overdose risk, as well as suspected fentanyl exposure, and willingness to use take-home rapid test strips to detect fentanyl contamination in drugs or urine. Participants were then trained to use the test strips and were given ten to take home.

RESULTS

Among 93 eligible participants, the mean age was 27 years (SD = 4.8), 56% (n = 52) of participants were male, and 56% (n = 52) were white. Over one third (n = 34, 37%) had a prior overdose. The vast majority (n = 86, 92%) of participants wanted to know if there was fentanyl in their drug supply prior to their use. Sixty-five (70%) participants reported concern that their drugs were contaminated with fentanyl. After the brief training, nearly all participants (n = 88, 95%) reported that they planned to use the test strips.

CONCLUSIONS

More than 90% of participants reported willingness to use rapid test strips regardless of having ever overdosed, suggesting that rapid fentanyl testing is an acceptable harm reduction intervention among young people who use drugs in Rhode Island. Study follow-up is ongoing to determine whether, how, and under what circumstances participants used the rapid test strips and if a positive result contributed to changes in overdose risk behavior.

Industry Payments to Physicians for Opioid Products, 2013-2015

OBJECTIVES

To identify payments that involved opioid products from the pharmaceutical industry to physicians.

METHODS

We used the Open Payments program database from the Centers for Medicare and Medicaid Services to identify payments involving an opioid to physicians between August 2013 and December 2015. We used medians, interquartile ranges, and ranges as a result of heavily skewed distributions to examine payments according to opioid product, abuse-deterrent formulation, nature of payment, state, and physician specialty.

RESULTS

During the study, 375 266 nonresearch opioid-related payments were made to 68 177 physicians, totaling $46 158 388. The top 1% of physicians received 82.5% of total payments in dollars. Abuse-deterrent formulations constituted 20.3% of total payments, and buprenorphine marketed for addiction treatment constituted 9.9%. Most payments were for speaking fees or honoraria (63.2% of all dollars), whereas food and beverage payments were the most frequent (93.9% of all payments). Physicians specializing in anesthesiology received the most in total annual payments (median = $50; interquartile range = $16-$151).

CONCLUSIONS

Approximately 1 in 12 US physicians received a payment involving an opioid during the 29-month study. These findings should prompt an examination of industry influences on opioid prescribing.

Extraction of cloransulam-methyl from soil with subcritical water and supercritical CO2

Cloransulam-methyl was extracted from soil samples with supercritical CO2, subcritical water and conventional organic solvents. Supercritical CO2 was less efficient than conventional organic solvents; polarity modifiers had no impact on extraction efficiency. Extraction with supercritical CO2 exhibited a strong temperature dependence. Water was as effective as strong organic solvents for the extraction of cloransulam-methyl; however cloransulam-methyl hydrolyzed when extracted at 150 degrees C. Extraction temperature was the most important variable in increasing the efficiency and rate of extraction, while extraction pressure was not a significant variable.

Effect of temperature and moisture on the degradation and sorption of florasulam and 5-hydroxyflorasulam in soil

The degradation rate and sorption characteristics of the triazolopyrimidine sulfonanilide herbicide florasulam and its principal degradation product 5-hydroxyflorasulam (5-OH-florasulam) were determined as a function of temperature and moisture in three different soils. The half-life for degradation of florasulam ranged from 1.0 to 8.5 days at 20-25 degrees C and from 6.4 to 85 days at 5 degrees C. The half-life for degradation of 5-OH-florasulam ranged from 8 to 36 days at 20-25 degrees C and from 43 to 78 days at 5 degrees C. The degradation rate of both compounds was strongly influenced by temperature, with activation energies ranging from 57 to 95 kJ/mol for florasulam and from 27 to 74 kJ/mol for 5-OH florasulam. Soil moisture content had negligible impact on the degradation rate. Apparent (nonequilibrium) sorption coefficients for florasulam and 5-OH-florasulam at 0 days after treatment (DAT) were 0.1-0.6 L/kg and increased linearly with time for both florasulam and 5-OH-florasulam (r(2) > 0.90) to levels as high as 12-23 L/kg. Heats of adsorption were calculated on one soil as a function of time. Heat of adsorption values for both florasulam and 5-OH-florasulam increased as incubation time increased and the amount of each compound decreased; values were near 0 kJ/mol initially and increased to a maximum of 91 and 66 kJ/mol for florasulam and 5-OH-florasulam, respectively.

Photolytic degradation of florasulam on soil and in water

The rate and pathway of degradation in the presence of light for the triazolopyrimidine herbicide florasulam was determined on soil and in aqueous systems. Florasulam was exposed to natural sunlight for up to 32 days; solar irradiance was measured with either chemical actinometers or by radiometry. The quantum yield for direct photodegradation in a sterile, buffered aqueous solution was determined to be 0.096; an analogous quantum yield for the sum of direct and indirect photodegradation on soil was 0.245. The quantum yields were used to estimate half-lives due to photodegradation as a function of season and temperature. Estimated half-lives due to photodegradation in summer at 40 degrees N latitude were 14 days on soil and 36 days in sterile, buffered water. Photodegradation was much faster in a natural water system, with a measured half-life of 3.3 days in summer at 51.5 degrees N latitude, indicating that indirect photolytic processes will be important contributors to photodegradation of florasulam in aqueous environments.

Extraction of tricyclazole from soil and sediment with subcritical water

The use of subcritical water to extract tricyclazole from soils and sediments was examined. Extraction efficiency and kinetics were determined as a function of temperature, sample age, sample matrix, sample size, and flow rate. Extraction temperature was the most influential experimental factor affecting extraction efficiency and kinetics, with increasing temperature (up to 150 degrees C) yielding faster and higher efficiency extractions. Higher extraction temperatures were also important for quantitative recovery of tricyclazole from aged samples. Extraction at 50 degrees C yielded 97% recoveries from samples aged 1 day but only 30% recoveries for samples aged 202 days, whereas extraction at 150 degrees C yielded recoveries of 85-100% that were independent of incubation time and sample matrix, with the exception of one sediment that contained a large amount of organic matter. Sample extracts from subcritical water extraction were generally a pale yellow color, contrasted with a dark brown color from organic solvent extractions of the same matrixes. Less sample cleanup was therefore required prior to analysis, with the total time for the extraction and analysis of a single sample being approximately 2 h. Subcritical water extraction is an effective technique for the rapid and quantitative extraction of tricyclazole from soils and sediments.

Collection of peripheral blood progenitor cells (PBPC) based on a rising WBC and platelet count significantly increases the number of CD34+ cells

The kinetics of mobilization and optimal timing of peripheral blood progenitor cell (PBPC) collection were evaluated in 190 patients with multiple myeloma undergoing stem cell harvest after mobilization with cyclophosphamide, prednisone and G-CSF. There was a strong correlation between the WBC count and the number of CD34+ cells circulating in peripheral blood (r = 0.875). Initiating leukapheresis based on rising WBC and platelet counts rather than on a fixed day increased the mean number of CD34+ cells 115% (9.7 to 20.9 x 10(6) CD34+ cells/kg; P = 0.010) for the total of all leukaphereses and 59% for the total of all CD34-selected products (5.1 to 8.1 x 10(6) CD34+ cells/kg; P = 0.011). Although the yield and purity of the CD34-selected product were not significantly affected (P > or = 0.071), the percentage of patients with concentrations of CD34+ cells in the initial leukapheresis of > 1% increased from 47% to 70% (P = 0.004). The mean purity of the selected product was related to the starting percentage: 48.9% if < 1% and 81.5% if > or = 1% (P < 0.001). Collection of stem cells based on rising WBC and platelet counts significantly increased the number of CD34+ cells in leukaphereses and CD34-selected products in comparison with collection on a fixed day.

Transplantation of CD34+ hematopoietic progenitor cells

We have developed an avidin-biotin immunoadsorption technique in conjunction with a monoclonal anti-CD34 antibody that is capable of selecting CD34+ progenitor cells from marrow and mobilized peripheral blood. Clinical studies with these CD34+ selected cells have shown that the cells are capable of rapid and durable engraftment. In addition, there is significantly less infusional toxicity to the patient because the volume in which the CD34+ selected cells are contained is much less than that of a typical marrow or apheresis buffy coat. Selection of CD34+ progenitor cells also offers other potential advantages, including T-cell depletion of allografts and tumor cell depletion of autografts. CD34+ selection can also be used to facilitate other manipulations of marrow and peripheral blood, including gene transfection, ex vivo stem cell expansion, tumor purging, and progenitor cell banking. Future graft engineering studies are expected to clarify these relationships and enable refinement of the graft to the point at which GVHD can be minimized, graft survival maximized, and relapse-free survival prolonged.

Stem-cell factor in aplastic anemia: in vitro expression in bone marrow stroma and fibroblast cultures

In vitro expression of stem-cell factor (SCF) by bone marrow (BM) cells of 30 patients with aplastic anemia (AA) has been analyzed at the mRNA and protein levels. While no deficiencies were found in SCF mRNA expression, low levels of soluble SCF protein were measured in poorly growing AA stroma cultures. The SCF protein concentration in the supernatant and the confluence of AA stroma growth were found to correlate (R = 0.70). Defective proliferation was observed in the majority (20/30) of AA stroma cultures and was paralleled by poor growth of homogeneous cultures of fibroblasts from the same marrow sample. AA stroma growth was enhanced by addition of exogenous SCF in combination with interleukin-11 (IL-11), leukemia inhibitory factor (LIF), and basic fibroblast growth factor (bFGF). Our results demonstrate that deficient growth of stroma cells results in decreased production of SCF. Therefore, SCF and other stroma-derived cytokines may be of therapeutic value in AA patients with documented defects within the BM microenvironment.

Office-based testing for antibody to human immunodeficiency virus in urology patients

Knowledge of the status of a patient regarding antibody to human immunodeficiency virus type 1 (HIV-1) may be important in many clinical situations. Consequently, we evaluated a rapid test for antibody to HIV-1 peptides that might be suitable for a physician office practice. We evaluated the time necessary to learn to do the test, and test performance using a reference panel and a seroconversion panel as well as 200 clinical specimens. Personnel who were previously unfamiliar with immunoassays learned the test procedure within 30 minutes. All reference specimens were interpreted correctly. One clinical sample reacted in the test but the result was not confirmed by Western blot. The rapid, peptide-based test was easy to use and performance was comparable to currently licensed tests performed at clinical laboratories.

Evaluation of blood collected on filter paper for detection of antibodies to human immunodeficiency virus type 1

This study was undertaken to evaluate the sensitivity and specificity of a commercial enzyme immunoassay in detecting antibody to human immunodeficiency virus type 1 using whole-blood specimens collected onto filter paper. Results obtained with specimens collected onto filter paper were comparable with those obtained with the corresponding serum or plasma specimens.

Quantitative autoradiographic analysis of estradiol retention by cells in the preoptic area, hypothalamus and amygdala

These experiments were done to compare quantitatively, on a cell-by-cell basis, estradiol retention by cells in the medial preoptic area, arcuate nucleus, ventrolateral subdivision of the ventromedial nucleus, and the caudal half of the medial nucleus of the amygdala. The steroid autoradiograms were prepared from 2 mu sections of brains from ovariectomized, adrenalectomized adult female rats that had been infused intravenously with [3H] estradiol (E2) in a regimen which kept circulating hormone concentration at or above proestrus levels for 3-4 h. Even in these brain regions, containing the most dense collections of E2-concentrating cells, a maximum of only 27-61% of the cells concentrated E2. Therefore, in these regions only a particular subset of the cells retain hormone; other cells in the region do not retain hormone. Frequency distribution histograms of the number of grains per cell versus the number of cells in each region showed a wide range in the amount of E2 retained per cell, and no modes among E2-retaining cells. The data followed a distribution markedly different from that predicted by a simple Poisson distribution, confirming that E2-retention does not result from a random, passive process such as diffusion. The overall quantitative characteristics of the frequency distribution histograms were similar across the four brain areas. Therefore, we propose that the different E2-sensitive functions of these brain areas must depend on differences in the neural connectivity or differences in hormone regulated peptide content of the areas.

An autoradiographic study of projections ascending from the midbrain central gray, and from the region lateral to it, in the rat

Ascending projections from the midbrain central gray (CG) and from the region lateral to it were traced in the rat using tritiated amino acid autoradiography. Leucine or a cocktail of amino acids (leucine, proline, lysine, histidine, and tyrosine) were used as tracers. In addition to projections within the midbrain, ascending fibers follow three trajectories. The ventral projection passes through the ventral tegmental region of Tsai and the medial forebrain bundle to reach the hypothalamus, preoptic area, caudoputamen, substantia innominata, stria terminalis, and amygdala. There are labeled fibers in the diagonal bands of Broca and medial septum, and terminal labeling in the lateral septum, nucleus accumbens, olfactory tubercle, and frontal cortex. The dorsal periventricular projection terminates in the midline and intralaminar thalamic nuclei. The ventral periventricular projection follows the ventral component of the third ventricle into the hypothalamus, passing primarily through the dorsal hypothalamic area and labeling the rostral hypothalamus and preoptic area. Projections from the region lateral to the CG are similar, but exhibit stronger proximal, and weaker distal, projections. Rostral levels of the CG send heavier projections to the fields of Forel and the zona incerta, but fewer fibers through the supraoptic decussation, than do caudal levels. Ascending projections from the CG are both strong and widespread. Strong projections to the limbic system and the intralaminar thalamic nuclei provide an anatomical substrate for CG involvement in nociception and affective responses.

Reversible tubular lesion in pregnancy-induced hypertension detected by urinary beta 2-microglobulin

Serum and urine beta 2-microglobulin concentrations were measured in 17 primigravidas with mild pregnancy-induced hypertension and nine normotensive control patients matched for gestational age. Serum beta 2-microglobulin and creatinine clearance values were not different between the two groups but urinary excretion of beta 2-microglobulin was three times higher in the hypertensive patients. This difference disappeared within seven days of delivery. These results indicate that a reversible renal tubular lesion occurs in pregnancy-induced hypertension even in the absence of detectable proteinuria.

Autoradiographic identification of estradiol-concentrating cells in the spinal cord of the female rat

The topography and number of estradiol (E)-concentrating cells in the lower lumbar and sacral segments of the spinal cord of the female rat have been examined by the steroid autoradiography method. A nuclear-saturating does of E was administered by intravenous infusion, which kept blood estrogen at or above proestrus levels for 3.5-4 h, much longer than usual for steroid receptor studies. The cord segments selected for examination are known to receive somatosensory information relevant for estrogen-dependent behavior, and to contain some of the motoneurons for epaxial muscles responsible for this behavior. Small numbers of E-concentrating cells were found in the dorsal portion of the gray matter of L4, L5, L6 and the sacral segments. These cells were found in lamina II, in the midline region which includes lamina X, and the medial portions of laminae III, IV and V when they cross in the midline. E-concentrating cells were also found in the lateral portions of laminae III, IV, and V, and in lamina VII. Virtually no E-concentrating cells were found in the ventral portion of the gray matter or in the white matter. The spinal cord had few E-concentrating cells compared to the hypothalamus.

An autoradiographic study of the efferent connections of the ventromedial nucleus of the hypothalamus

Efferent projections from the ventromedial nucleus of the hypothalamus (VMN) were traced using tritiated amino acid autoradiography in albino rats. Ascending fibers passed through the anterior hypothalamus. Labelled fibers and terminal fields were seen in the preoptic area, bed nucleus of the stria terminalis, substantia innominata, the anterior amygdaloid area, diagonal bands of Broca and lateral septum. Fibers also projected laterally from VMN and entered the supraoptic commissures and zona incerta. These lateral projections were responsible for the fibers observed in the cerebral peduncle, the amygdala, the thalamus and the reticular formation. Fibers descending in a medial position projected through the posterior hypothalamus and then swept dorsally to terminate in the mesencephalic and pontine central grey. A projection from VMN into the median eminence was noted. The overall patterns of projection from different parts of VMN were similar; differences that existed were primarily in the relative strengths of the different projections. The efferent projections from VMN are extensive, well organized, and would appear capable of supporting significant physiological actions on extra-hypothalamic structures.

Ejaculatory and postejaculatory behavior of male and female rats: effects of sex hormones and electric shock

Ejaculatory patterns were observed in normally reared, postpuberally castrated male and female rats treated with sex hormones and electrical shock in adulthood. In a preliminary experiment, 3 females treated with 50 microgram estradiol benzoate (EB) and 500 microgram progesterone (P) showed intromission and ejaculatory behavior when subjected to shock. Refractory periods were abnormally short and there was almost no postejaculatory vocalization. In Experiment 1, males and females were tested with electrical shock following daily treatment with 32 microgram EB with and without 500 microgram P on the test day. There was no difference between males and females in preejaculatory behavior, but females displayed abbreviated refractory periods and no postejaculatory vocalization. Progesterone had no observed effect. In Experiment 2 castrated males and females were subjected to shock after treatment with 8 microgram EB per day for 3 weeks. No P was given. Again females showed drastically reduced refractory periods and little vocalization. In Experiment 3, males and females treated with TP and shock displayed ejaculatory patterns, normal refractory periods and vocalization. Results show that female rats are capable of exhibiting the ejaculatory response without sex hormone treatment in perinatal life or androgen treatment in adulthood. It was also demonstrated that there is a sex difference in the postejaculatory behavior shown by estrogen-treated male and female rats.

Autoradiographic localization of estradiol-concentrating cells in the female hamster brain

Autoradiographic methods were used to study the location of estrogen-concentrating cells in the brain of the female hamster. In the hypothalamus, well-labelled cells were reliably found in the posterior medial preoptic area (MPOA), the anterior hypothalamus (AHA), and the ventromedial (VM), arcuate (ARC) and ventral premammillary nuclei (VPM). In the limbic system, well-labelled cells were found in the ventro-lateral septum, bed nucleus of the stria terminalis, and the medial and cortical nuclei of the amygdala. Labelled cells, in small numbers, were also detected in the mesencephalic central gray (CG), lateral hypothalamus, subiculum and entorhinal cortex. The neuroanatomical pattern of estrogen-concentrating cells in the hamster supports the concept of a generalized vertebrate pattern. Furthermore, a comparison of hamster and rat patterns of cellular 3H-estradiol (3H-E2) concentration appears to suggest that species differences in their responsiveness to estrogen may be paralleled by differences in estrogen binding.

Sexual behavior: normal male patterning in androgenized female rats

Female rats treated with testosterone as neonates and as adults exhibited a temporal patterning of male copulatory behavior identical to that of normal males, although such females displayed few intromission reflexes and almost no ejaculatory patterns. With prenatal, postnatal, and adult testosterone treatment, female rats displayed all the characteristic masculine responses and intervals, including the ultrasonic postejaculatory vocalization.