A systematic analysis and data mining of opioid-related adverse events submitted to the FAERS database

The opioid epidemic has become a serious national crisis in the United States. An indepth systematic analysis of opioid-related adverse events (AEs) can clarify the risks presented by opioid exposure, as well as the individual risk profiles of specific opioid drugs and the potential relationships among the opioids. In this study, 92 opioids were identified from the list of all Food and Drug Administration (FDA)-approved drugs, annotated by RxNorm and were classified into 13 opioid groups: buprenorphine, codeine, dihydrocodeine, fentanyl, hydrocodone, hydromorphone, meperidine, methadone, morphine, oxycodone, oxymorphone, tapentadol, and tramadol. A total of 14,970,399 AE reports were retrieved and downloaded from the FDA Adverse Events Reporting System (FAERS) from 2004, Quarter 1 to 2020, Quarter 3. After data processing, Empirical Bayes Geometric Mean (EBGM) was then applied which identified 3317 pairs of potential risk signals within the 13 opioid groups. Based on these potential safety signals, a comparative analysis was pursued to provide a global overview of opioid-related AEs for all 13 groups of FDA-approved prescription opioids. The top 10 most reported AEs for each opioid class were then presented. Both network analysis and hierarchical clustering analysis were conducted to further explore the relationship between opioids. Results from the network analysis revealed a close association among fentanyl, oxycodone, hydrocodone, and hydromorphone, which shared more than 22 AEs. In addition, much less commonly reported AEs were shared among dihydrocodeine, meperidine, oxymorphone, and tapentadol. On the contrary, the hierarchical clustering analysis further categorized the 13 opioid classes into two groups by comparing the full profiles of presence/absence of AEs. The results of network analysis and hierarchical clustering analysis were not only consistent and cross-validated each other but also provided a better and deeper understanding of the associations and relationships between the 13 opioid groups with respect to their adverse effect profiles.

Evaluating Confounding Control in Estimations of Influenza Antiviral Effectiveness in Electronic Health Plan Data

Observational studies of oseltamivir use and influenza complications could suffer from residual confounding. Using negative control risk periods and a negative control outcome, we examined confounding control in a health-insurance-claims-based study of oseltamivir and influenza complications (pneumonia, all-cause hospitalization, and dispensing of an antibiotic). Within the Food and Drug Administration's Sentinel System, we identified individuals aged ≥18 years who initiated oseltamivir use on the influenza diagnosis date versus those who did not, during 3 influenza seasons (2014-2017). We evaluated primary outcomes within the following 1-30 days (the primary risk period) and 61-90 days (the negative control period) and nonvertebral fractures (the negative control outcome) within days 1-30. We estimated propensity-score-matched risk ratios (RRs) per season. During the 2014-2015 influenza season, oseltamivir use was associated with a reduction in the risk of pneumonia (RR = 0.72, 95% confidence interval (CI): 0.70, 0.75) and all-cause hospitalization (RR = 0.54, 95% CI: 0.53, 0.55) in days 1-30. During days 61-90, estimates were near-null for pneumonia (RR = 1.04, 95% CI: 0.95, 1.15) and hospitalization (RR = 0.94, 95% CI: 0.91, 0.98) but slightly increased for antibiotic dispensing (RR = 1.14, 95% CI: 1.08, 1.21). The RR for fractures was near-null (RR = 1.09, 95% CI: 0.99, 1.20). Estimates for the 2016-2017 influenza season were comparable, while the 2015-2016 season had conflicting results. Our study suggests minimal residual confounding for specific outcomes, but results differed by season.

Using inpatient electronic medical records to study influenza for pandemic preparedness

BACKGROUND

We assessed the ability to identify key data relevant to influenza and other respiratory virus surveillance in a large-scale US-based hospital electronic medical record (EMR) dataset using seasonal influenza as a use case. We describe characteristics and outcomes of hospitalized influenza cases across three seasons.

METHODS

We identified patients with an influenza diagnosis between March 2017 and March 2020 in 140 US hospitals as part of the US FDA's Sentinel System. We calculated descriptive statistics on the presence of high-risk conditions, influenza antiviral administrations, and severity endpoints.

RESULTS

Among 5.1 million hospitalizations, we identified 29,520 hospitalizations with an influenza diagnosis; 64% were treated with an influenza antiviral within 2 days of admission, and 25% were treated >2 days after admission. Patients treated >2 days after admission had more comorbidities than patients treated within 2 days of admission. Patients never treated during hospitalization had more documentation of cardiovascular and other diseases than treated patients. We observed more severe endpoints in patients never treated (death = 3%, mechanical ventilation [MV] = 9%, intensive care unit [ICU] = 26%) or patients treated >2 days after admission (death = 2%, MV = 14%, ICU = 32%) than in patients treated earlier (treated on admission: death = 1%, MV = 5%, ICU = 23%, treated within 2 days of admission: death = 1%, MV = 7%, ICU = 27%).

CONCLUSIONS

We identified important trends in influenza severity related to treatment timing in a large inpatient dataset, laying the groundwork for the use of this and other inpatient EMR data for influenza and other respiratory virus surveillance.

Clinical Data Extraction During Public Health Emergencies: A Blockchain Technology Assessment

OBJECTIVE

We sought to explore the technical and legal readiness of healthcare institutions for novel data-sharing methods that allow clinical information to be extracted from electronic health records (EHRs) and submitted securely to the Food and Drug Administration's (FDA's) blockchain through a secure data broker (SDB).

MATERIALS AND METHODS

This assessment was divided into four sections: an institutional EHR readiness assessment, legal consultation, institutional review board application submission, and a test of healthcare data transmission over a blockchain infrastructure.

RESULTS

All participating institutions reported the ability to electronically extract data from EHRs for research. Formal legal agreements were deemed unnecessary to the project but would be needed in future tests of real patient data exchange. Data transmission to the FDA blockchain met the success criteria of data connection from within the four institutions' firewalls, externally to the FDA blockchain via a SDB.

DISCUSSION

The readiness survey indicated advanced analytic capability in hospital institutions and highlighted inconsistency in Fast Healthcare Interoperability Resources format utilitzation across institutions, despite requirements of the 21st Century Cures Act. Further testing across more institutions and annual exercises leveraging the application of data exchange over a blockchain infrastructure are recommended actions for determining the feasibility of this approach during a public health emergency and broaden the understanding of technical requirements for multisite data extraction.

CONCLUSION

The FDA's RAPID (Real-Time Application for Portable Interactive Devices) program, in collaboration with Discovery, the Critical Care Research Network's PREP (Program for Resilience and Emergency Preparedness), identified the technical and legal challenges and requirements for rapid data exchange to a government entity using the FDA blockchain infrastructure.

Clinical Data Extraction During Public Health Emergencies: A Blockchain Technology Assessment

OBJECTIVE

We sought to explore the technical and legal readiness of healthcare institutions for novel data-sharing methods that allow clinical information to be extracted from electronic health records (EHRs) and submitted securely to the Food and Drug Administration's (FDA's) blockchain through a secure data broker (SDB).

MATERIALS AND METHODS

This assessment was divided into four sections: an institutional EHR readiness assessment, legal consultation, institutional review board application submission, and a test of healthcare data transmission over a blockchain infrastructure.

RESULTS

All participating institutions reported the ability to electronically extract data from EHRs for research. Formal legal agreements were deemed unnecessary to the project but would be needed in future tests of real patient data exchange. Data transmission to the FDA blockchain met the success criteria of data connection from within the four institutions' firewalls, externally to the FDA blockchain via a SDB.

DISCUSSION

The readiness survey indicated advanced analytic capability in hospital institutions and highlighted inconsistency in Fast Healthcare Interoperability Resources format utilitzation across institutions, despite requirements of the 21st Century Cures Act. Further testing across more institutions and annual exercises leveraging the application of data exchange over a blockchain infrastructure are recommended actions for determining the feasibility of this approach during a public health emergency and broaden the understanding of technical requirements for multisite data extraction.

CONCLUSION

The FDA's RAPID (Real-Time Application for Portable Interactive Devices) program, in collaboration with Discovery, the Critical Care Research Network's PREP (Program for Resilience and Emergency Preparedness), identified the technical and legal challenges and requirements for rapid data exchange to a government entity using the FDA blockchain infrastructure.

Theoretical modelling of single-mode lasing in microcavity lasers via optical interference injection

The effective manipulation of mode oscillation and competition is of fundamental importance for controlling light emission in semiconductor lasers. Here we develop a rate equation model which considers the spatially modulated gain and spontaneous emission, which are inherently governed by the ripple of the vacuum electromagnetic field in a Fabry-Pérot (FP) microcavity. By manipulating the interplay between the spatial oscillation of the vacuum field and external optical injection via dual-beam laser interference, single longitudinal mode operation is observed in a FP-type microcavity with a side mode suppression ratio exceeding 40 dB. An exploration of this extended rate equation model bridges the gap between the classical model of multimode competition in semiconductor lasers and a quantum-optics understanding of radiative processes in microcavities.

Broadband, wide-angle antireflection in GaAs through surface nano-structuring for solar cell applications

We demonstrate broadband and wide-angle antireflective surface nanostructuring in GaAs semiconductors using variable dose electron-beam lithography (EBL). Various designed structures are written with EBL on a positive EB-resist coated GaAs and developed followed by shallow inductively coupled plasma etching. An optimized nanostructured surface shows a reduced surface reflectivity down to less than 2.5% in the visible range of 450–700 nm and an average reflectance of less than 4% over a broad near-infrared wavelength range from 900–1400 nm. The results are obtained over a wide incidence angle of 33.3°. This study shows the potential for anti-reflective structures using a simpler reverse EBL process which can provide optical absorption or extraction efficiency enhancement in semiconductors relevant to improved performance in solar photovoltaics or light-emitting diodes.

Determination of Atrazine in Water by Magnetic Particle Immunoassay: Collaborative Study

A collaborative study was performed to determine mean recovery and precision for analysis of atrazine in drinking and surface waters by immunoassay. The study design was based on the blind duplicate test plan for collaborative studies. Three blank waters (municipal drinking water, well water, and surface water) were spiked at 3 atrazine levels. Two water samples with naturally incurred atrazine loads were also spiked with atrazine at 3 levels. In the enzyme-linked immunoassay method, the water sample is mixed with a pesticide–enzyme conjugate and added to paramagnetic particles with triazine-specific antibodies attached. After separation of antibody-bound atrazine and atrazine–enzyme conjugate from free components, the bound enzyme conjugate catalyzes a reaction producing a colored end product. The color developed is inversely proportional to the original concentration of atrazine in the water sample. Fourteen laboratories participated in the collaborative study. Data were analyzed for repeatability and reproducibility, and average recoveries at the spike levels were calculated. Over the concentration range tested, the mean recovery of atrazine spiked into blank and pesticide-contaminated waters was 104%. Overall RSDRaveraged about 40% for atrazine concentrations near the method detection limit (0.05 μg/L) and about 15% at concentrations above 5 times the detection limit (0.25 μg/L). Corresponding single-analyst RSDr values were 24 and 10%. Recovery and precision for the 3 blank water matrixes and the waters that had been naturally contaminated with atrazine showed no significant differences. The magnetic particle immunoassay

Harnessing scientific literature reports for pharmacovigilance. Prototype software analytical tool development and usability testing

Objectives

We seek to develop a prototype software analytical tool to augment FDA regulatory reviewers’ capacity to harness scientific literature reports in PubMed/MEDLINE for pharmacovigilance and adverse drug event (ADE) safety signal detection. We also aim to gather feedback through usability testing to assess design, performance, and user satisfaction with the tool.

Methods

A prototype, open source, web-based, software analytical tool generated statistical disproportionality data mining signal scores and dynamic visual analytics for ADE safety signal detection and management. We leveraged Medical Subject Heading (MeSH) indexing terms assigned to published citations in PubMed/MEDLINE to generate candidate drug-adverse event pairs for quantitative data mining. Six FDA regulatory reviewers participated in usability testing by employing the tool as part of their ongoing real-life pharmacovigilance activities to provide subjective feedback on its practical impact, added value, and fitness for use.

Results

All usability test participants cited the tool’s ease of learning, ease of use, and generation of quantitative ADE safety signals, some of which corresponded to known established adverse drug reactions. Potential concerns included the comparability of the tool’s automated literature search relative to a manual ‘all fields’ PubMed search, missing drugs and adverse event terms, interpretation of signal scores, and integration with existing computer-based analytical tools.

Conclusions

Usability testing demonstrated that this novel tool can automate the detection of ADE safety signals from published literature reports. Various mitigation strategies are described to foster improvements in design, productivity, and end user satisfaction.

Use of data mining at the Food and Drug Administration

Objectives This article summarizes past and current data mining activities at the United States Food and Drug Administration (FDA).

Target audience We address data miners in all sectors, anyone interested in the safety of products regulated by the FDA (predominantly medical products, food, veterinary products and nutrition, and tobacco products), and those interested in FDA activities.

Scope Topics include routine and developmental data mining activities, short descriptions of mined FDA data, advantages and challenges of data mining at the FDA, and future directions of data mining at the FDA.

Emergency use authorization for intravenous peramivir: evaluation of safety in the treatment of hospitalized patients infected with 2009 H1N1 influenza A virus

BACKGROUND

On 23 October 2009, the US Food and Drug Administration (FDA) issued an Emergency Use Authorization (EUA) for intravenous peramivir, an unapproved antiviral, to treat suspected or confirmed 2009 H1N1 influenza A virus infection. Eligible hospitalized patients were unresponsive to or unable to tolerate available antivirals or lacked dependable oral or inhaled drug delivery routes. The EUA required healthcare providers to report medication errors, selected adverse events (AEs), serious AEs, and deaths to the FDA.

METHODS

An FDA safety team analyzed reports submitted to the Adverse Event Reporting System (AERS) and sought follow-up in selected cases.

RESULTS

The FDA received AERS reports for 344 patients (including 28 children and 3 pregnant women). Many patients were critically ill on mechanical ventilation (41%) and renal replacement therapies (19%); 38% had received oseltamivir. The most frequently reported serious AEs by MedDRA preferred term were death (15%), H1N1 influenza (8%), respiratory failure (8%), acute renal failure (7%), and acute respiratory distress syndrome (7%). Six medication errors were reported. Most deaths occurred among patients who were obese, immunosuppressed, aged >65 years, or received oseltamivir. Rash was the only treatment-emergent AE attributable to peramivir. Influenza severity, comorbidities, and concomitant medications confounded additional peramivir AE assessments. Missing clinical and laboratory data precluded evaluation of some reports.

CONCLUSIONS

Many peramivir recipients under the EUA were critically ill and at risk for influenza-related complications. The safety data were insufficient to assess whether peramivir affected outcome or caused adverse reactions other than rash. Clinical trials in hospitalized patients with serious influenza infections should provide additional information.

The current status of targeted therapy for non-small cell lung cancer

Lung cancer accounts for more cancer-related deaths than any other malignancy in Australia and worldwide. Non-small cell lung cancer (NSCLC) accounts for about 85% of lung cancers and is associated with a 5-year survival of only 15%. Treatment with platinum-based doublets in the first-line setting and single agent chemotherapy in the second-line setting has improved survival and quality of life in patients with NSCLC. However, the benefits associated with chemotherapy are modest and serve to stress the need for novel therapeutic approaches. In the last decade a range of targeted therapies has been evaluated in NSCLC. Dramatic and often durable responses were seen in patients treated with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) gefitinib and erlotinib particularly in females, non-smokers, patients of East Asian ethnicity and those with adenocarcinomas - a group subsequently found to be enriched for tumours with activating EGFR mutations. Large randomized phase III trials have since established a role for EGFR TKI in the second- and third-line setting as well as a potential role for the monoclonal antibodies bevacizumab and cetuximab, directed at vascular endothelial growth factor and EGFR, respectively, in the combination with chemotherapy in the first-line setting. Recently it has been shown that patients with EGFR mutations may benefit from gefitinib in the first-line setting. Other promising agents under evaluation are inhibitors of the insulin-like growth factor-1 receptor and inhibitors of recently described ALK gene rearrangements.

Polycystic liver diseases

Polycystic liver diseases (PCLDs) are genetic disorders with heterogeneous etiologies and a range of phenotypic presentations. PCLD exhibits both autosomal or recessive dominant pattern of inheritance and is characterized by the progressive development of multiple cysts, isolated or associated with polycystic kidney disease, that appear more extensive in women. Cholangiocytes have primary cilia, functionally important organelles (act as mechanosensors) that are involved in both normal developmental and pathological processes. The absence of polycystin-1, 2, and fibrocystin/polyductin, normally localized to primary cilia, represent a potential mechanism leading to cyst formation, associated with increased cell proliferation and apoptosis, enhanced fluid secretion, abnormal cell-matrix interactions, and alterations in cell polarity. Proliferative and secretive activities of cystic epithelium can be regulated by estrogens either directly or by synergizing growth factors including nerve growth factor, IGF1, FSH and VEGF. The abnormalities of primary cilia and the sensitivity to proliferative effects of estrogens and different growth factors in PCLD cystic epithelium provide the morpho-functional basis for future treatment targets, based on the possible modulation of the formation and progression of hepatic cysts.

Exendin-4, a glucagon-like peptide 1 receptor agonist, protects cholangiocytes from apoptosis

BACKGROUND AND AIMS

Progression of chronic cholestatic disorders towards ductopenia results from the dysregulation of cholangiocyte survival, with cell death by apoptosis prevailing over compensatory proliferation. Currently, no therapy is available to sustain cholangiocyte survival in the course of those disorders. It was recently shown that cholangiocytes express the glucagon-like peptide-1 receptor (GLP-1R); its activation results in enhanced proliferative reaction to cholestasis. The GLP-1R selective agonist exendin-4 sustains pancreatic beta cell proliferation and prevents cell death by apoptosis. Exendin-4 is now employed in humans as a novel therapy for diabetes. The aim of the present study was to verify whether exendin-4 is effective in preventing cholangiocyte apoptosis.

METHODS

In vitro, tests were carried out to determine if exendin-4 is able to prevent apoptosis of cholangiocytes isolated from normal rats induced by glycochenodeoxycholic acid (GCDCA); in vivo, animals subjected to 1 week of bile duct ligation and to a single intraperitoneal injection of CCl(4) were treated with exendin-4 for 3 days.

RESULTS

Exendin-4 prevented GCDCA-induced Bax mitochondrial translocation, cytochrome c release and an increase in caspase 3 activity. Phosphatidylinositol 3-kinase, but not cAMP/protein kinase A or Ca(2+)/calmodulin-dependent protein kinase inhibitors, neutralised the effects of exendin-4. In vivo, exendin-4 administration prevented the increase in TUNEL (terminal deoxynucleotidyl transferase-mediated triphosphate end-labelling)-positive cholangiocytes and the loss of bile ducts observed in bile duct-ligated rats treated with CCl(4).

CONCLUSION

Exendin-4 prevents cholangiocyte apoptosis both in vitro and in vivo; such an effect is due to the ability of exendin-4 to counteract the activation of the mitochondrial pathway of apoptosis. These findings support the hypothesis that exendin-4 may be effective in slowing down the progression of cholangiopathies to ductopenia.

Estrogens stimulate the proliferation of human cholangiocarcinoma by inducing the expression and secretion of vascular endothelial growth factor

BACKGROUND

Estrogens may induce the proliferation of neoplastic cells by activating neo-angiogenesis.

AIM

To evaluate the effect of estrogens on the expression of vascular endothelial growth factor (VEGF) and related receptors (VEGF-R) in human cholangiocarcinoma and the role played by VEGF in mediating the proliferative effects of estrogens.

METHODS

Seven biopsies of intra-hepatic cholangiocarcinoma and the HuH-28 cell lines were investigated. Cell proliferation was measured by both PCNA Western blot and MTS proliferation assay.

RESULTS

By immunohistochemistry, biopsies of human cholangiocarcinoma stained positively for VEGF-A and VEGF-C and related receptors. HuH-28 cells expressed VEGF-A, -C, and VEGFR-1, -2, -3 and, their protein level was enhanced by 17beta-estradiol in association with the stimulation of cell proliferation. 17beta-Estradiol-stimulated proliferation of HuH-28 cells was blocked by 70% by VEGF-TRAP, a receptor-based VEGF inhibitor. 17beta-Estradiol induced the secretion of VEGF in the supernatant of HuH-28 cells. The stimulatory effect of 17beta-estradiol on the protein expression of VEGF-A, VEGF-C and VEGFR-1, -2, -3 was blocked by antagonists of ER (Ici182,780) or insulin-like growth factor 1-receptor (alphaIR3).

CONCLUSIONS

With the limitations of experiments performed in a cell line, our study indicates that VEGF plays a major role in mediating the proliferative effects of estrogens on human cholangiocarcinoma.

The use of pulse oximetry as a screening assessment for paediatric neurogenic dysphagia

PURPOSE

Early screening and intervention for dysphagia is crucial to offset potential outcomes such as compromised nutrition or reduced respiratory function. Current paediatric dysphagia screening tests are subjective with poor sensitivity and specificity. The present study examined whether an objective method, pulse oximetry (measuring oxygen saturation (SpO2) levels), could differentiate between children with and without dysphagia, in relation to (1) Average pre-feeding baseline SpO2 levels; (2) Average feeding SpO2 levels; (3) Average post-feeding SpO2 levels; and (4) The number of events of oxygen desaturation pre-, during and after feeding.

METHODS

Nine participants with chronic neurological disability (CND) (7 F, 2 M) (9; 7-15; 11 years) and nine control participants matched for age (9; 5-16; 0 years) and sex were assessed using a clinical bedside evaluation (CBE) and pulse oximetry.

RESULTS

A statistically significant difference was found in SpO2 levels between the two groups (p < 0.001) during oral feeding only (sensitivity, 88.9%; specificity, 88.9%). Only three children with dysphagia experienced 'events' of SpO2 desaturation during feeding.

CONCLUSION

Pulse oximetry may provide a useful adjunct to the CBE for dysphagia screening, with average SpO2 levels during feeding predicting those with and without dysphagia with moderate levels of sensitivity and specificity. The finding of individual variation in desaturation 'events', however, warrants the provision of further data on large homogenous populations to provide definitive criterion for pathological SpO2 levels associated with dysphagia during oral feeding.

Predictors of early leaving from the cotton spinning mill environment in newly hired workers

OBJECTIVE

This longitudinal study aimed to identify the predictors of leaving during the first year of employment from the cotton spinning mill environment in newly hired workers.

METHODS

One hundred and ninety eight consecutively appointed new employees were investigated by questionnaire, lung function test, and skin test. They were examined before employment and at the end of the 1st week, and the 1st, 3rd, 6th, and 12th month after starting work and when possible before leaving their job. 572 personal dust sampling and 191 endotoxin measurements were performed to assess the environmental exposure. For the univariate analysis chi2, Student t tests, ANOVA, and Kruskall Wallis tests were used. Cox proportional hazards analysis was used to identify factors associated with leaving the job.

RESULTS

Fifty three per cent of workers left the mill environment during their first working year. Work related lower respiratory tract symptoms reported at the third month were associated with an increase rate of leaving the industry compared to those remaining in the industry (25% v 4.8%; p<0.005). Having respiratory symptoms at the first month of work predicted those leaving the industry at some point in the next 11 months. According to the Cox model, increasing age and having work related lower respiratory tract symptoms were found to be predictors for leaving job at the first working year. Atopic status, dust and endotoxin levels, and lung function changes were not consistently predictive of workers who left the industry in the follow up period.

CONCLUSION

This study demonstrated that work related respiratory symptoms can predict workers likely to leave the cotton mill environment during the first year of employment, but atopy or acute lung function changes do not.

Integration of pharmacotherapy for opioid addiction into HIV primary care for HIV/hepatitis C virus-co-infected patients

Pharmacotherapy for substance abuse is a rapidly evolving field comprising both old and new effective treatments for substance use. Opiate agonist therapy has been shown to diminish and often eliminate opiate use. This behavior change has resulted in the reduced transmission of many infections, including HIV, hepatitis C virus (HCV), and an enhanced quality of life. For the past 35 years, the provision of opioid agonist therapy has been limited to opioid treatment programmes. Opioid treatment programmes treat approximately 200,000 of the estimated million opiate-addicted individuals in the United States. With the need to increase the number of treatment opportunities available for opioid-dependent patients, Congress passed the Drug Addiction Treatment Act of 2000, which allows for the treatment of opioid dependence using buprenorphine by a properly licensed physician, including HIV primary care physicians. The integration of buprenorphine treatment for opioid addiction into HIV primary care thus provides a new treatment paradigm to address substance abuse in patients with HIV and HCV infections.

Co-occurring Hepatitis C, substance use, and psychiatric illness: treatment issues and developing integrated models of care

Hepatitis C virus (HCV) infection is transmitted by injection drug use and associated with psychiatric conditions. Patients with drug use or significant psychiatric illness have typically been excluded from HCV treatment trials noting the 1997 National Institutes of Health Consensus Statement on HCV that indicated active drug use and major depressive illness were contraindications to treatment of HCV infection. However, the 2002 NIH Consensus Statement recognized that these patients could be effectively treated for HCV infection and recommended that treatment be considered on a case-by-case basis. Treating HCV infection in these patients is challenging, with drug use relapse possibly leading to psychosocial instability, poor adherence, and HCV reinfection. Interferon therapy may exacerbate preexisting psychiatric symptoms. Co-occurring human immunodeficiency virus or hepatitis B virus provide additional challenges, and access to ancillary medical and psychiatric services may be limited. Patients with co-occurring HCV infection, substance use, and psychiatric illness can complete interferon treatment with careful monitoring and aggressive intervention. Clinicians must integrate early interventions for psychiatric conditions and drug use into their treatment algorithm. Few programs or treatment models are designed to manage co-occurring substance use, psychiatric illness, and HCV infection and therapy. The National Institute on Drug Abuse convened a panel of experts to address the current status and the long-range needs through a 2-day workshop, Co-occurring Hepatitis C, Substance Abuse, and Psychiatric Illness: Addressing the Issues and Developing Integrated Models of Care. This conference report summarizes current data, medical management issues, and strategies discussed.

Hepatitis C infection and injection drug use: the role of hepatologists in evolving treatment efforts

Treatment regimens for both substance abuse and hepatitis C infection are complex and evolving. New pharmacotherapy for opioid addiction allows for office-based treatment and, thus, an opportunity for expanded treatment in the context of hepatitis C infection. The current article addresses the newly evolving, complex issues in the medical management of hepatitis C and injection drug use.

Addressing the Need for Treatment Paradigms for Drug-Abusing Patients with Multiple Morbidities

Persons who use and abuse drugs are at risk for multiple morbidities that involve addiction, bloodborne infectious diseases, and sexually transmitted diseases, in addition to psychiatric illness and social instability. Infectious diseases acquired as a result of drug use can diffuse into non-drug using populations through other high-risk behaviors. Drug users also have substantial comorbidities from noncommunicable diseases and complications that can affect virtually every organ system in the body. Diagnosis of comorbidities and complications associated with drug abuse usually occurs late in the disease course, particularly for persons who are disenfranchised and have limited or no access to medical care. Medical management of these comorbid conditions constitutes a significant challenge. Directly observed therapy (DOT) can be useful but needs to conform to the needs of the targeted treatment population for full efficacy. DOT may have its greatest impact with drug users destabilized by cocaine or methamphetamine use but has yet to be fully investigated in this patient population.

Bloodborne and sexually transmitted infections in drug abusers in the United States, Latin America, the Caribbean, and Spain

In the United States, approximately 1 million Americans are infected with human immunodeficiency virus (HIV), and several thousand new infections are reported each year. More than one-third of cases of acquired immunodeficiency syndrome (AIDS) are associated with injection drug use. An estimated 1.8 million adults and children are currently living with HIV in Latin America and the Caribbean, and injection drug abuse remains a major factor in initial exposures to HIV in these parts of the world. Although only 3 cases of AIDS related to drug abuse have been reported in Bolivia, a country with a nascent epidemic, >19,000 cases of AIDS have been reported in Argentina and >22,000 in Brazil, with a significant number associated with injection drug use. Extensive epidemiological and clinical research has been conducted in the United States and elsewhere to determine the extent and nature of the problem and to design and develop interventions (prevention and treatment) for drug abusers infected with HIV. The articles in this supplement present a current view of the nature and extent of the bloodborne and sexually transmitted infections in drug abusers and their partners in the Western Hemisphere.

Interventions for metabolic and endocrine complications of human immunodeficiency virus/acquired immune deficiency syndrome and illicit drug use

Illicit drug use and concurrent infection with human immunodeficiency virus (HIV) are associated with metabolic and endocrine complications that may include lipid, carbohydrate, and endocrine metabolism disorders and nutritional deficiencies. Interventions for these metabolic and endocrine complications range from micronutrient supplementation to hormone-replacement therapy. We present the current strategies for the management of metabolic and endocrine disorders of HIV/acquired immunodeficiency virus and drug use. In addition, the panel members (contributing authors of the present supplement) recommend further research to determine the nature and extent of problems and to design better and effective therapies.

Substance abuse and HIV infection

Substance abuse facilitates the spread of HIV infection and complicates its management. Successful treatment of HIV disease and other comorbidities in substance abusers requires treatment of substance abuse. At the Clinical Pathway of the Ryan White CARE Act 2002 All Grantee Conference held in Washington, DC, in August 2002, Henry Francis, MD, discussed characteristics of substance abuse in the United States and obstacles and approaches to successful treatment.

Clinical effects of air filters in homes of asthmatic adults sensitized and exposed to pet allergens

BACKGROUND

Despite medical advice, many pet-allergic asthma sufferers refuse to remove the pet to which they are sensitized from their home.

OBJECTIVE

We aimed to assess the clinical effects of air cleaners in the homes of adult asthma patients sensitized and exposed to cats and/or dogs.

METHODS

We performed a randomized, parallel-group study of 30 asthmatic adults sensitized to and sharing a home with cats or dogs. The effects of placing air cleaners in the living room and bedroom for 12 months and using high efficiency particulate air filter vacuum cleaners (active group) were compared with using these vacuum cleaners alone (control group). Measures of airway responsiveness, treatment requirement, lung function, peak flow, reservoir and airborne allergen were recorded before, during and after the interventions. A beneficial clinical response was assessed in terms of a 'combined asthma outcome'. This was defined as a two or more doubling dose improvement in bronchial hyper-reactivity to histamine and/or a reduction in treatment requirement of at least one step change on the British Thoracic Society guidelines for asthma treatment.

RESULTS

A beneficial clinical response was observed in 10/15 subjects in the active group compared with 3/15 in the control group after 12 months intervention (P = 0.01). No significant differences between the active and control groups were detected for changes in measures of lung function, reservoir pet allergen and airborne pet allergen during the study.

CONCLUSION

Whilst the study design has not allowed complete exclusion of a placebo effect, we believe that this pragmatic study of adult asthmatic patients sensitized and exposed to pets resulted in a small, but significant improvement in combined asthma outcome.

Monocyte CD14 response following endotoxin exposure in cotton spinners and office workers

BACKGROUND

Monocyte cell surface CD14 acts as the major lipopolysaccharide (LPS) binding structure, and as such is of interest in the etiology of LPS induced disease.

METHODS

The objective was to assess change in monocyte cell surface CD14 and CD4+ CD25+ lymphocytes in a group of cotton workers exposed to LPS over a working week, and to compare this to changes in office workers. Twenty-five cotton workers and nine office workers were studied. Monocyte CD14 fluorescence was measured by flow cytometry, on samples taken pre-shift on a Monday morning (baseline/pre-exposure), and subsequently after 6 and 72 hr. The majority of cotton workers were exposed to at least 1 EU/m(3) of endotoxin over a working shift, and some highly exposed (between 100 and 400 EU/m(3)).

RESULTS

After 6 hr of work in the mill, cotton workers developed a significant upregulation in CD14 in comparison to office workers (P = 0.016), whereas CD14 expression had returned to levels not significantly differing from the office workers at 72 hr after first work exposure (P = 0.426).

CONCLUSIONS

We propose that CD14 expression on monocytes may help to determine the mechanism of action of lipopolysaccharide in producing respiratory ill health, and may ultimately play a role in monitoring the health effect associated with LPS exposure in the workplace.

Clinical consequences of marijuana

As documented in national surveys, for the past several years, marijuana has been the most commonly abused drug in the United States, with approximately 6% of the population 12 years and older having used the drug in the month prior to interview. The use of marijuana is not without significant health hazards. Marijuana is associated with effects on almost every organ system in the body, ranging from the central nervous system to the cardiovascular, endocrine, respiratory/pulmonary, and immune systems. Research presented in this special supplement will show that in addition to marijuana abuse/dependence, marijuana use is associated in some studies with impairment of cognitive function in the young and old, fetal and developmental consequences, cardiovascular effects (heart rate and blood pressure changes), respiratory/pulmonary complications such as chronic cough and emphysema, impaired immune function leading to vulnerability to and increased infections, and the risk of developing head, neck, and/or lung cancer. In general, acute effects are better studied than those of chronic use, and more studies are needed that focus on disentangling effects of marijuana from those of other drugs and adverse environmental conditions.

Bile acid feeding increased proliferative activity and apical bile acid transporter expression in both small and large rat cholangiocytes

Bile acids (BA) enter cholangiocytes by the Na(+)-dependent apical BA transporter (ABAT). By this mechanism, taurocholate (TC) and taurolithocholate (TLC) increase cholangiocyte proliferation. No in vivo studies exist regarding the anatomical sites involved in BA-regulation of cholangiocyte growth. Specific cholangiocyte subpopulations participate in BA-regulated proliferation. Proliferation was assessed in liver sections by determining the number of proliferating cellular nuclear antigen (PCNA)-positive cholangiocytes and cytokeratin-19 (CK-19)-positive ducts. We isolated small and large cholangiocytes from rats fed for 1 week TC, TLC, or BA control diet and determined PCNA and ABAT expression and BA transport activity. We evaluated if TC and TLC induction of ABAT expression was dependent on activation of PKC alpha. DNA replication was active only in large normal cholangiocytes. TC and TLC feeding increased proliferation of large cholangiocytes, induced the de novo activation of proliferation of small cholangiocytes, overexpression of ABAT and BA transport activity in large cholangiocytes, and de novo expression of ABAT and BA transport activity in small cholangiocytes. BA-stimulated ABAT expression was dependent on PKC activation in cholangiocytes. TC and TLC stimulate proliferation of small and large cholangiocytes associated with PKC-dependent up-regulation of ABAT.

Regression of cholangiocyte proliferation after cessation of ANIT feeding is coupled with increased apoptosis

Cholangiocyte proliferation and loss through apoptosis occur in cholestatic liver diseases. Our aim was to determine the mechanisms of apoptosis in an animal model of ductal hyperplasia. Rats were fed alpha-naphthylisothiocyanate (ANIT) for 2 wk and subsequently fed normal chow for 1, 2, and 4 wk. Proliferation was assessed in sections by morphometry and in small and large cholangiocytes by proliferating cellular nuclear antigen immunoblots and measurement of cAMP levels. Apoptosis and reactive oxygen species (ROS) levels were also assessed. ANIT feeding increased small and large cholangiocyte proliferation and apoptosis. Cessation of ANIT feeding was associated with decreased proliferation and a further increase in apoptosis in small and large cholangiocytes. Cholangiocytes from ANIT-fed rats or exposed to ANIT in vitro showed increased apoptosis and ROS generation. ANIT-induced duct injury results in enhanced proliferation and apoptosis in small and large cholangiocytes. The mechanism of ANIT-induced apoptosis may be due to ROS generation induced directly by ANIT. Our model has implications for understanding the pathophysiology of cholangiopathies (characterized by the coexistence of cholangiocyte apoptosis and proliferation).

Gastrin inhibits cholangiocarcinoma growth through increased apoptosis by activation of Ca2+-dependent protein kinase C-alpha

BACKGROUND/AIMS

We determined the role of gastrin in the regulation of cholangiocarcinoma growth.

METHODS

We evaluated for the functional presence of cholecystokinin (CCK)-B/gastrin receptors in the cholangiocarcinoma cell lines, Mz-ChA-1, HuH-28 and TFK-1. We determined the effect of gastrin on the growth of Mz-ChA-1, HuH-28 and TFK-1 cells. We evaluated the effect of gastrin on growth and apoptosis of Mz-ChA-1 in the absence or presence of inhibitors for CCK-A (L-364, 718) and CCK-B/gastrin (L-365, 260) receptors, the intracellular Ca2+ chelator (BAPTA/AM), and the protein kinase C (PKC)-alpha inhibitor, H7. We evaluated if gastrin effects on Mz-ChA-1 growth and apoptosis are associated with membrane translocation of PKC-alpha.

RESULTS

Gastrin inhibited DNA synthesis of Mz-ChA-1, HuH-28 and TFK-1 cells in a dose- and time-dependent fashion. The antiproliferative effect of gastrin on Mz-ChA-1 cells was inhibited by L-365, 260, H7 and BAPTA/AM but not L-364, 718. Gastrin induced membrane translocation of PKC-alpha. The inhibition of growth of Mz-ChA-1 cells by gastrin was associated with increased apoptosis through a PKC-dependent mechanism.

CONCLUSIONS

Gastrin inhibits the growth of Mz-ChA-1, HuH-28 and TFK-1 cells. Gastrin inhibits growth and induces apoptosis in Mz-ChA-1 cells through the Ca2+-dependent PKC-alpha. The data suggest a therapeutic role for gastrin in the modulation of cholangiocarcinoma growth.

Targeted disruption of the Kvlqt1 gene causes deafness and gastric hyperplasia in mice

The KvLQT1 gene encodes a voltage-gated potassium channel. Mutations in KvLQT1 underlie the dominantly transmitted Ward-Romano long QT syndrome, which causes cardiac arrhythmia, and the recessively transmitted Jervell and Lange-Nielsen syndrome, which causes both cardiac arrhythmia and congenital deafness. KvLQT1 is also disrupted by balanced germline chromosomal rearrangements in patients with Beckwith-Wiedemann syndrome (BWS), which causes prenatal overgrowth and cancer. Because of the diverse human disorders and organ systems affected by this gene, we developed an animal model by inactivating the murine Kvlqt1. No electrocardiographic abnormalities were observed. However, homozygous mice exhibited complete deafness, as well as circular movement and repetitive falling, suggesting imbalance. Histochemical study revealed severe anatomic disruption of the cochlear and vestibular end organs, suggesting that Kvlqt1 is essential for normal development of the inner ear. Surprisingly, homozygous mice also displayed threefold enlargement by weight of the stomach resulting from mucous neck cell hyperplasia. Finally, there were no features of BWS, suggesting that Kvlqt1 is not responsible for BWS.

Cholinergic system modulates growth, apoptosis, and secretion of cholangiocytes from bile duct-ligated rats

BACKGROUND & AIMS

To investigate the role of the cholinergic system in regulation of cholangiocyte functions, we evaluated the effects of vagotomy on cholangiocyte proliferation and secretion in rats that underwent bile duct ligation (BDL rats).

METHODS

After bile duct ligation (BDL), the vagus nerve was resected; 7 days later, expression of M3 acetylcholine receptor was evaluated. Cholangiocyte proliferation was assessed by morphometry and measurement of DNA synthesis. Apoptosis was evaluated by light microscopy and annexin-V staining. Ductal secretion was evaluated by measurement of secretin-induced choleresis, secretin receptor (SR) gene expression, and cyclic adenosine 3',5'-monophosphate (cAMP) levels.

RESULTS

Vagotomy decreased the expression of M3 acetylcholine receptors in cholangiocytes. DNA synthesis and ductal mass were markedly decreased, whereas cholangiocyte apoptosis was increased by vagotomy. Vagotomy decreased ductal secretion. Forskolin treatment prevented the decrease in cAMP levels induced by vagotomy, maintained cholangiocyte proliferation, and decreased cholangiocyte apoptosis caused by vagotomy in BDL rats. Cholangiocyte secretion was also maintained by forskolin.

CONCLUSIONS

Vagotomy impairs cholangiocyte proliferation and enhances apoptosis, leading to decreased ductal mass in response to BDL. Secretin-induced choleresis of BDL rats was virtually eliminated by vagotomy in association with decreased cholangiocyte cAMP levels. Maintenance of cAMP levels by forskolin administration prevents the effects of vagotomy on cholangiocyte proliferation, apoptosis, and secretion.

Acute carbon tetrachloride feeding selectively damages large, but not small, cholangiocytes from normal rat liver

The aim of this study was to develop a model of selective duct damage restricted to hormone-responsive segments corresponding to the ducts damaged in primary biliary cirrhosis (PBC). Carbon tetrachloride (CCl4) was fed by gavage to rats, and 2, 7, 14, and 28 days later, small and large cholangiocytes were isolated. Apoptosis was determined in situ by morphology and in purified cholangiocytes by assessment of nuclear fragmentation by 4, 6-diamidino-2-phenylindole (DAPI) staining. Cholangiocyte proliferation was evaluated in situ by morphometry of liver sections stained for cytokeratin-19 (CK-19) and by proliferating cellular nuclear antigen (PCNA) staining in liver sections and in purified cholangiocytes by PCNA gene expression. Ductal secretion was assessed by measurement of secretin receptor (SR) gene expression and secretin-induced cyclic adenosine 3',5'-monophosphate (cAMP) synthesis and secretin-induced choleresis. Two days after CCl4 administration, there was an increased number of small ducts, but a reduction of large ducts. Apoptosis, observed only in large ducts, was associated with decreased DNA synthesis and ductal secretion. Conversely, small cholangiocytes expressed de novo the SR gene and secretin-stimulated cAMP synthesis 2 days after CCl4 treatment. Proliferation of large cholangiocytes was delayed until 7 days, which was associated with a transient increase in ductal secretion in vivo. CCl4 effects on cholangiocytes were reversed by day 28. CCl4 treatment causes a decrease in large duct mass as a result of a higher rate of apoptosis and absence of initial proliferation in large cholangiocytes. These processes were concomitant with a decrease of ductal secretion in large cholangiocytes. Small cholangiocytes appear resistant to CCl4-induced apoptosis, and proliferate and transiently compensate for loss of proliferative and secretory activity of large cholangiocytes.

Bile acid feeding induces cholangiocyte proliferation and secretion: evidence for bile acid-regulated ductal secretion

BACKGROUND & AIMS

We have shown that taurocholate (TC) and taurolithocholate (TLC) interact in vitro with normal cholangiocytes, increasing DNA synthesis, secretin receptor (SR) gene expression, and adenosine 3',5'-cyclic monophosphate (cAMP) synthesis. To further extend these in vitro studies, we tested the hypothesis that bile acids (BAs) directly stimulate cholangiocyte proliferation and secretion in vivo.

METHODS

After feeding with TC or TLC (1% for 1-4 weeks), we assessed the following in vivo: (1) ductal proliferation by both morphometry and immunohistochemistry for proliferating cell nuclear antigen (PCNA) and measurement of [3H]thymidine incorporation; and (2) the effect of secretin on bile secretion and bicarbonate secretion in vivo. Genetic expression of H3-histone and SR and intracellular cAMP levels were measured in isolated cholangiocytes.

RESULTS

After BA feeding, there was an increased number of PCNA-positive cholangiocytes and an increased number of ducts compared with control rats. [3H]Thymidine incorporation, absent in control cholangiocytes, was increased in cholangiocytes from BA-fed rats. In BA-fed rats, there was increased SR gene expression (approximately 2.5-fold) and secretin-induced cAMP levels (approximately 3.0-fold) in cholangiocytes, which was associated with de novo secretin-stimulated bile flow and bicarbonate secretion.

CONCLUSIONS

These data indicate that elevated BA levels stimulate ductal secretion and cholangiocyte proliferation.

Relationship between exhaled nitric oxide and childhood asthma

The purpose of the study was to determine if exhaled nitric oxide levels in children varied according to their asthmatic and atopic status. Exhaled nitric oxide was measured in a sample of 93 children attending the North West Lung Centre, Manchester, United Kingdom, for the clinical evaluation of a respiratory questionnaire being developed as a screening tool in general practice. The clinical assessment included full lung function, skin prick testing, and exercise challenge. Children were said to be asthmatic either by consensus decision of three independent consultant pediatricians, who reviewed all the clinical results except the nitric oxide measurements, or by positive exercise test. Atopic asthmatic children had higher geometric mean exhaled nitric oxide levels (consensus decision, 12.5 ppb [parts per billion] 95% CI, 8.3 to 18. 8; positive exercise test, 12.2 ppb 95% CI, 7.6 to 19.7) than did nonatopic asthmatic children (3.2 ppb 95% CI, 2.3 to 4.6; 3.2 ppb 95% CI, 2.0 to 5.0), atopic nonasthmatic children (3.8 ppb 95% CI, 2. 7 to 5.5; 5.7 ppb 95% CI, 4.1 to 8.0), or nonatopic nonasthmatic children (3.4 ppb 95% CI, 2.8 to 4.1; 3.5 ppb 95% CI, 3.0 to 4.1). Thus, exhaled nitric oxide was raised in atopic asthmatics but not in nonatopic asthmatics, and these nonatopic asthmatics had levels of exhaled nitric oxide similar to those of the nonasthmatics whether atopic or not.

The agony and the ecstasy

The issue of helping patients with their sexual needs has sparked heated debate. In the search for understanding, Hilary Francis describes how she assisted a disabled couple to have sex.

gamma-Interferon inhibits secretin-induced choleresis and cholangiocyte proliferation in a murine model of cirrhosis

BACKGROUND/AIMS

Cholangiocyte proliferation is associated with increased secretin receptor gene expression and secretin-induced choleresis. Since gamma-interferon has antiproliferative effects, we tested the hypothesis that gamma-interferon inhibits ductal proliferation and secretin-stimulated choleresis associated with cirrhosis.

METHODS

Mice were treated with 0.1 ml of 25% carbon tetrachloride intraperitoneally twice weekly and 5% alcohol in drinking water for 12 weeks to induce cirrhosis and subsequently gamma-interferon 10(5) intramuscularly was administered daily for 10 weeks. We measured the effects of carbon tetrachloride and gamma-interferon on liver collagen content by morphometric analysis and hydroxyproline content. We measured the effects of gamma-interferon on ductal mass by morphometry and on ductal secretion by assessment of secretin receptor gene expression and secretin-induced choleresis.

RESULTS

Compared to controls, there was an increase in liver hydroxyproline content of carbon tetrachloride-treated mice with histologic evidence of cirrhosis. Gamma-interferon treatment significantly decreased collagen liver content with loss of histologic features of cirrhosis. Morphometry revealed an increased number of bile ducts in cirrhotic mice as compared to controls or cirrhotics who received gamma-interferon. Secretin receptor mRNA levels were higher in cirrhotic mice compared to controls but this increase was inhibited by gamma-interferon. Secretin stimulated ductal secretion in cirrhotic mice but not control or cirrhotic mice who received gamma-interferon.

CONCLUSIONS

We have established a murine model for cirrhosis and have shown, consistent with our hypothesis, that gamma-interferon decreases collagen content, ductal mass and secretin-induced choleresis incirrhotic mice.

The use of pamidronate in hypertrophic pulmonary osteoarthropathy (HPOA)

BACKGROUND

Hypertrophic pulmonary osteoarthropathy (HPOA) secondary to bronchogenic carcinoma can be associated with severe, disabling pain which is not always responsive to conventional treatment.

AIM

To report on the use of pamidronate to control resistant pain in HPOA in three cases.

METHODS

A retrospective review of reported pain, chest X-ray and radionuclide bone scans was made.

RESULTS

Pain relief was achieved in all three cases together with reduced radiolabel uptake in two cases.

CONCLUSIONS

Pamidronate appears to be an effective therapy for HPOA. Further investigation is warranted.

Chronic bronchitis in textile workers

BACKGROUND

Exposure to cotton is known to produce a specific occupational disease known as byssinosis. A large population of textile workers was investigated to determine whether such exposure was also associated with chronic bronchitis once other possible aetiological factors had been accounted for.

METHODS

A total of 2991 workers were investigated for the presence of symptoms compatible with chronic bronchitis. An MRC adapted respiratory questionnaire and MRC definition of chronic bronchitis were used for diagnostic labelling. Current and lifetime exposure to dust was estimated by personal and work area sampling, and the use of records of retrospective dust levels previously measured over the preceding 10 years. Airborne endotoxin exposure was measured using a quantitative turbidometric assay. Lung function tests were performed to measure forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). A control group of workers exposed to man-made fibre textiles was identified. The comparative prevalence of chronic bronchitis in the two populations was assessed, allowing for sex, age, smoking habit, and ethnic origin. Two case referent studies were also performed; cases of chronic bronchitis were separately matched with controls from the cotton and control populations to determine the effect of the symptomatic state on lung function.

RESULTS

After controlling for smoking (pack years), workers in a cotton environment were significantly more likely to suffer from chronic bronchitis and this was most marked in workers over 45 years of age (odds ratio 2.51 (CI 1.3 to 4.9); p < 0.01). Regression analysis of all possible influencing parameters showed that cumulative exposure to cotton dust was significantly associated with chronic bronchitis after the effects of age, sex, smoking, and ethnic group were accounted for (p < 0.0005). In the intra-cotton population case control study a diagnosis of chronic bronchitis was associated with a small decrement in lung function compared with controls: percentage predicted FEV1 in cases 81.4% (95% CI 78.3 to 84.6), controls 86.7% (84.9 to 88.5); FVC in cases 89.9% (95% CI 87.0 to 92.9), controls 94.6% (92.8 to 96.4). After controlling for cumulative past exposure and pack years of smoking the effect of the diagnostic state remained significant for both FEV1 (p < 0.01) and FVC (p < 0.05).

CONCLUSIONS

Chronic bronchitis is more prevalent in cotton workers than in those working with man-made fibre and exposure is additive to the effect of smoking. The diagnosis of chronic bronchitis is associated with a small but significant decrement in lung function.

Naproxen concentrations in plasma and synovial fluid and effects on prostanoid concentrations

OBJECTIVE

To test the hypothesis that unbound concentrations of naproxen in synovial fluid (SF) and plasma (P) are equal over a drug dosage interval at steady state or after a single dose of drug. The relationship between plasma and SF concentrations of naproxen, respectively, and prostaglandin concentrations were also examined.

METHODS

Paired, sequential, total, and unbound naproxen concentrations were determined in plasma and SF in 2 groups of 6 patients. A single dose group was given naproxen 500 mg. The chronic dose group was given 500 mg bd for 7 days before collection of blood and SF samples. The effect of naproxen on prostanoid production by clotting whole blood (thromboxane B2, TXB2) and in SF (PGE2, 6-keto-PGF1 alpha) was determined by radioimmunoassay.

RESULTS

Average area under the curve (AUC) of unbound (U) naproxen concentrations against time in plasma and SF were the same over a dosage interval at steady state (ratio AUCU,SF/AUCU,P, 1.12 +/- 0.18; p = 0.108), but not after a single acute dose (AUCU,SF/AUCU,P, 1.34 +/- 0.32; p = 0.044). Data from the single dose study revealed that the mean (+/- SD) of the concentrations required for 50% inhibition (EC50) of platelet derived TXB2 by total naproxen was 7.7 +/- 4.4 micrograms/ml (n = 5) and for unbound drug 25.4 +/- 22.0 ng/ml (n = 5). SF prostanoid concentrations after both acute and chronic dosing were low, as expected, but temporal and dose relationships of prostanoid concentrations with SF naproxen could not be discerned. However, this may reflect study design.

CONCLUSIONS

The AUC of unbound naproxen in SF and plasma were similar at steady state. Plasma concentrations correlated with inhibition of TXB2 generation by platelets. There was sustained depression of PG concentrations in SF beyond the time suggested by plasma drug concentrations.

Interleukin-6 and tumor necrosis factor in the pathogenesis of adverse reactions after treatment of lymphatic filariasis and onchocerciasis

Adverse reactions following treatment of onchocerciasis and bancroftian filariasis are common and frequently severe. They are generally caused not by direct drug toxicity but by host inflammatory responses to dying microfilariae. To define the responsible mechanism, serial blood levels of interleukin-6 (IL-6) and tumor necrosis factor (TNF) were studied in 15 microfilaria-positive patients (10 with bancroftian filariasis, 5 with onchocerciasis) and 4 microfilaria-negative persons after diethylcarbamazine treatment. Elevations in IL-6 correlated with the occurrence and severity of clinical symptoms after treatment; for the onchocerciasis patients IL-6 levels directly reflected pretreatment intensity of infection. Serum TNF levels also rose but did not correlate directly with infection intensity or reaction severity. Microfilaria-negative controls remained asymptomatic with no significant rise in either cytokine. These findings suggest an etiologic role for systemically elevated cytokines in the inflammatory reactions developing after treatment of filarial infections in humans.

Disruption of epithelial cell-matrix interactions induces apoptosis

Cell-matrix interactions have major effects upon phenotypic features such as gene regulation, cytoskeletal structure, differentiation, and aspects of cell growth control. Programmed cell death (apoptosis) is crucial for maintaining appropriate cell number and tissue organization. It was therefore of interest to determine whether cell-matrix interactions affect apoptosis. The present report demonstrates that apoptosis was induced by disruption of the interactions between normal epithelial cells and extracellular matrix. We have termed this phenomenon "anoikis." Overexpression of bcl-2 protected cells against anoikis. Cellular sensitivity to anoikis was apparently regulated: (a) anoikis did not occur in normal fibroblasts; (b) it was abrogated in epithelial cells by transformation with v-Ha-ras, v-src, or treatment with phorbol ester; (c) sensitivity to anoikis was conferred upon HT1080 cells or v-Ha-ras-transformed MDCK cells by reverse-transformation with adenovirus E1a; (d) anoikis in MDCK cells was alleviated by the motility factor, scatter factor. The results suggest that the circumvention of anoikis accompanies the acquisition of anchorage independence or cell motility.