Improvements in Air Quality and Health Outcomes Among California Medicaid Enrollees Due to Goods Movement Actions.

INTRODUCTION: In 2006, the California Air Resources Board (CARB) and local air quality management districts implemented an Emission Reduction Plan for Ports and Goods Movement program (referred to hereinafter as GM policy actions) (CARB 2006). The GM policy actions comprise approximately 200 actions with an estimated investment value of $6 to $10 billion. These actions targeted the major sources and polluters related to goods movements, such as highways; ports and railyard trucks; ship fuel and shore power; cargo equipment; and locomotives. These actions aimed to reduce total statewide domestic GM emissions to 2001 levels or lower by the year 2010; to reduce the statewide diesel particulate matter (DPM) health risk from GM by 85% by the year 2020; and to reduce the nitrogen oxides (NOx) emissions from international GM in the South Coast Air Basin by 30% from projected 2015 levels and 50% from projected 2020 levels. The years 2006 and 2007 marked an important milestone in starting to regulate GM polluters and adopting stricter standards for traffic-related air pollution.This project aimed to examine the impact of the GM policy actions on reductions in ambient air pollution and subsequent improvements in health outcomes of Medi-Cal fee-for-service (FFS) beneficiaries with chronic conditions in 10 counties in California. Specifically, we examined whether the GM policy actions reduced air pollution near GMC corridors more than in control areas. We subsequently assessed whether there were greater decreases in emergency room (ER) visits and hospitalizations for enrollees with chronic conditions who lived in the GM corridors (GMCs) than for those who lived in other areas. METHODS: The study used a quasi-experimental design. We defined areas within 500 m of truck-permitted freeways and ports as GMCs. We further defined non-goods movement corridors (NGMCs) as locations within 500 m of truck-prohibited freeways or 300 m of a connecting roadway, and areas out of GMCs and NGMCs as controls (CTRLs). We defined years 2004-2007 as the pre-policy period and years 2008-2010 as the post-policy period. We developed linear mixed-effects land use regression models and created annual air pollution surfaces for nitrogen dioxide (NO2), fine particulate matter (PM2.5), and ozone (O3) across California for years 2004-2010 at a spatial resolution of 30 m, then assigned them to enrollees' home addresses.We used a retrospective cohort of 23,000 California Medicaid (Medi-Cal) FFS adult beneficiaries living in 10 California counties with six years of data (September 1, 2004, to August 31, 2010). Cohort beneficiaries had at least one of four chronic conditions, including asthma, chronic obstructive pulmonary disease (COPD), diabetes, and heart disease.We used a difference-in-differences (DiD) model to assess whether air pollutant concentration and health care utilization (ER visits and hospitalizations) for cohort beneficiaries declined more for those living in intervention corridors (GMCs, NGMCs) than those living in CTRLs. All the models controlled for age, sex, language spoken, race/ethnicity, number of comorbidities in baseline years, county, time-varying health indicator variables, and several neighborhood variables.To facilitate interpretation, we calculated the DiD estimates in each of the three years after the policy intervention. The DiD was used to assess the causal impact of regulatory policy on reductions of air pollution, as well as for the improvements in health outcomes.We explored whether improvements in health outcomes were due to the air pollution reduction by using a multi- level mediation model, in which the effect of GM actions on health outcomes was mediated through the effect of actual air pollution reductions in the post-policy years. We used the Generalized Structural Equation Models for the estimation and combined the effects of NO2 and PM2.5 in the model. To further verify the causal inferences of the GM actions on reductions of exposures and improvements in health outcomes, we performed sensitivity analyses with propensity score weighting. RESULTS: We observed statistically significant reductions in pollutant NO2 and PM2.5 concentrations for enrollees in all 10 counties. The enrollees in GMCs experienced greater reductions in NO2 and PM2.5 from the pre- to the post-policy periods than those in CTRLs. Greater reductions were also observed among beneficiaries living in NGMCs versus those in CTRLs, but those reductions were smaller than among beneficiaries living in GMCs. For O3 concentrations, an opposite trend was observed.Furthermore, we observed significantly greater reductions in ER visits for patients with asthma and COPD living in GMCs than those in CTRLS in the post-policy years. For example, we saw in the DiD modeling results there were 170 fewer ER visits for 1,000 beneficiaries with asthma per year in GMCs if the regionwide trend in the CTRL group was considered not related to the GM policy. Similarly, among the beneficiaries with COPD, there were 180 fewer ER visits per 1,000 patients estimated in the GMCs for the third year after the implementation of the policy.We also observed greater reductions in ER visits among those with asthma, when comparing NGMCs with CTRLs, but reductions were smaller than comparisons between GMCs and CTRLs. The ER visits for those with COPD, diabetes, and the total sample in NGMCs also had downward trends in the post-policy year in comparison with those in CTRLs but the differences were not statistically significant; similar phenomena were also observed for the ER visits among those with diabetes and heart diseases and in the total sample when GMCs versus CTRLs and GMCs versus NGMCs were compared. Although hospitalizations also decreased more in GMCs than in NGMCs and more in NGMCs than in CTRLs in the post-policy period, results were not statistically significant.Using the mediation models, we observed 0.129 more reductions in the expected number of ER visits among individuals with asthma for a composite reduction in one unit NO2 and one unit PM2.5 (DiD = -0.129, P < 0.05) from the pre-policy years to the post-policy years. The reductions in NO2 and PM2.5 due to policy change estimated by the mediation model are essentially the same as shown in the respective DiD models. Mediation analyses suggested that the effects of GM policy interventions on health improvements were largely due to exposure reductions. Finally, sensitivity analyses with propensity scores produced similar DiD results. CONCLUSIONS: This project has produced empirical evidence that air pollution control actions reduced pollution exposures among disadvantaged and susceptible populations. More importantly, our findings suggest that the reductions in air pollution led to health outcome improvements among low-income people with chronic conditions. Our investigation also contributed to scientific methods for assessing the health effects of long-term, large-scale, and complex regulatory actions with routinely collected pollutants and medical claims data. Therefore, the results strongly support both short-term and long-term efforts to improve air quality for all members of society and future studies on the impact of air pollution control policies.

How do changes in body mass index in infancy and childhood associate with cardiometabolic profile in adulthood? Findings from the Northern Finland Birth Cohort 1966 Study.

BACKGROUND/OBJECTIVE: Postnatal growth patterns leading to obesity may have adverse influences on future cardiometabolic health. This study evaluated age and body mass index (BMI) at infant BMI peak (BMIP) and childhood BMI rebound (BMIR) in relation to adult cardiometabolic outcomes in the Northern Finland Birth Cohort 1966. METHODS: BMI at various ages was calculated from frequent height and weight measurements obtained from child health and welfare clinical records. Age and BMI at BMIP and BMIR were derived from random effect models fitted at >0-1.5 years (N=3 265) and >1.5-13 years (N=4 121). Cardiometabolic outcomes were obtained from a clinical examination at age 31 years. Multiple regression models were used to analyse associations between the derived growth parameters and cardiometabolic outcomes. RESULTS: Age and BMI at BMIP were positively associated with adult BMI and waist circumference (WC), independently of birth weight and infant height growth (P<0.05). Later BMIR was associated with a better cardiometabolic profile: adult BMI and insulin were 14% lower, WC and triglycerides were 10% lower and the odds of metabolic syndrome (MetS) were 74% lower per 2 s.d. (1.86 years) higher age at BMIR (P<0.0001). BMI at rebound had generally weaker associations with cardiometabolic outcomes, which attenuated after adjustment for age at BMIR. CONCLUSIONS: Age and BMI at infant BMIP were associated with adult adiposity but not with other cardiometabolic outcomes. Earlier timing of BMIR was a risk factor of an adverse cardiometabolic profile, independently of early growth or BMI at rebound. Identifying growth patterns harmful to cardiovascular health will give opportunities for early interventions.

Factors associated with hospital admission and adverse outcome for COVID-19: Role of social factors and medical care.

BACKGROUND: Beyond sex, age, and various comorbidities, geographical origin and socioeconomic deprivation are associated with Coronavirus Disease (COVID-19) morbidity and mortality in the general population. We aimed to assess factors associated with severe forms of COVID-19 after a hospital emergency department visit, focusing on socioeconomic factors. METHODS: Patients with laboratory-confirmed COVID-19 attending the emergency department of Béclère Hospital (France) in March-April 2020 were included. Postal addresses were used to obtain two geographical deprivation indices at the neighborhood level. Factors associated with hospitalization and factors associated with adverse outcomes, i.e. mechanical ventilation or death, were studied using logistic and Cox analyses, respectively. RESULTS: Among 399 included patients, 321 were hospitalized. Neither geographical origin nor socioeconomic deprivation was associated with any of the outcomes. Being male, older, overweight or obese, diabetic, or having a neuropsychiatric disorder were independent risk factors for hospitalization. Among 296 patients hospitalized at Béclère Hospital, 91 experienced an adverse outcome. Older age, being overweight or obese, desaturation and extent of chest CT scan lesions>25% at admission (aHR: 2.2 [95% CI: 1.3-3.5]) and higher peak CRP levels and acute kidney failure (aHR: 2.0 [1.2-3.3]) during follow-up were independently associated with adverse outcomes, whereas treatment with hydrocortisone reduced the risk of mechanical ventilation or death by half (aHR: 0.5 [0.3-0.8]). CONCLUSION: No association between geographical origin or socioeconomic deprivation and the occurrence of a severe form of COVID-19 was observed in our population after arrival to the emergency department. Empirical corticosteroid use with hydrocortisone had a strong protective impact.

Micro magnetic resonance angiography of the finger in systemic sclerosis.

OBJECTIVE: To characterize vascular lesions in SSc disease with high-resolution magnetic resonance angiography (Micro-MRA) of the finger. METHODS: Eight SSc subjects and eight age- and sex-matched healthy controls were recruited for this study. Among the SSc subjects, the mean +/- s.d. age was 54.5 +/- 4.9 yrs, and the mean +/- s.d. duration of disease was 8.3 +/- 8.4 yrs. The numbers of SSc subjects that had telangiectasia, calcinosis and impaired finger flexion were 3, 2 and 3, respectively. The 2D time-of-flight micro-MRA was performed on a 3T clinical MRI scanner using a custom-designed finger coil with an in-plane resolution of 0.16 x 0.21 mm(2) and slice thickness of 1.2 mm. The data for the proper palmar digital artery lumen area, the number of visible dorsal digital veins and a semi-quantitative vascular score, which evaluates the overall integrity of digital vessels, were independently evaluated by two experienced reviewers who were blinded to the status of the subject. RESULTS: Micro-MRA detected significant differences in the digital vasculature between SSc subjects and healthy volunteers. The SSc subjects had a significantly decreased digital artery lumen area (0.13 +/- 0.06 vs 0.53 +/- 0.26 mm(2), P < 0.001), a reduced number of digital veins (0.63 +/- 1.06 vs 3.13 +/- 0.99, P = 0.001) and a lowered overall vascular score (1.75 +/- 1.04 vs 3.5 +/- 0.53, P = 0.001). The study also found that both the digital artery lumen area (Pearson's; r = -0.72, P = 0.044) and vascular scores (Spearman's; rho = -0.75, P = 0.047) of the SSc subjects were inversely correlated with the duration of the disease. CONCLUSIONS: Micro-MRA can be used to identify and quantitatively characterize the vascular disease in SSc fingers. The parameters derived from micro-MRA could potentially be used as prospective biomarkers for clinical evaluation.

New models for evaluation of radiation-induced lifetime cancer risk and its uncertainty employed in the UNSCEAR 2006 report.

Generalized relative and absolute risk models are fitted to the latest Japanese atomic bomb survivor solid cancer and leukemia mortality data (through 2000), with the latest (DS02) dosimetry, by classical (regression calibration) and Bayesian techniques, taking account of errors in dose estimates and other uncertainties. Linear-quadratic and linear-quadratic-exponential models are fitted and used to assess risks for contemporary populations of China, Japan, Puerto Rico, the U.S. and the UK. Many of these models are the same as or very similar to models used in the UNSCEAR 2006 report. For a test dose of 0.1 Sv, the solid cancer mortality for a UK population using the generalized linear-quadratic relative risk model is estimated as 5.4% Sv(-1) [90% Bayesian credible interval (BCI) 3.1, 8.0]. At 0.1 Sv, leukemia mortality for a UK population using the generalized linear-quadratic relative risk model is estimated as 0.50% Sv(-1) (90% BCI 0.11, 0.97). Risk estimates varied little between populations; at 0.1 Sv the central estimates ranged from 3.7 to 5.4% Sv(-1) for solid cancers and from 0.4 to 0.6% Sv(-1) for leukemia. Analyses using regression calibration techniques yield central estimates of risk very similar to those for the Bayesian approach. The central estimates of population risk were similar for the generalized absolute risk model and the relative risk model. Linear-quadratic-exponential models predict lower risks (at least at low test doses) and appear to fit as well, although for other (theoretical) reasons we favor the simpler linear-quadratic models.

Oxaliplatin added to the simplified bimonthly leucovorin and 5-fluorouracil regimen as second-line therapy for metastatic colorectal cancer (FOLFOX6). GERCOR.

For patients resistant to leucovorin (LV) and 5-fluorouracil (5-FU), the addition of oxaliplatin (85 or 100 mg/m2) to bimonthly LV-5-FU has given a response rate of 20-46%. The highest response rate has been observed with oxaliplatin 100 mg/m2 (FOLFOX2). The present phase II study (FOLFOX6) infused oxaliplatin (100 mg/m2) with LV (400 mg/m2) as a 2-h infusion on day 1, followed by bolus 400 mg/m2 and a 46-h infusion (2.4-3 g/m2) of 5-FU, every 2 weeks. Among the 60 patients treated, 16 (27%) had partial responses (95% confidence interval: 15-38), 27 (45%) had stable disease, 15 (25%) experienced disease progression and 2 (3%) had non-measurable disease. From the start of FOLFOX6, median progression-free survival was 5.3 months and median survival 10.8 months. From the 448 cycles analysed, NCI-CTC grade 3-4 toxicities per patient were: peripheral neuropathy 16%, nausea 7%, diarrhoea 7%, mucositis 5%, neutropenia 24%, thrombocytopenia 2%. Overall 26 (46%) patients experienced grade 3-4 toxicities. Because of toxicity, only 36% of the patients received > or = 90% of the scheduled oxaliplatin dose intensity. FOLFOX6 was active in pretreated patients resistant to LV-5-FU and is being investigated as first-line therapy. We are now investigating FOLFOX7, a regimen with a higher oxaliplatin dose intensity and a lower 5-FU dose.

HPLC analysis of putative amino acid neurotransmitters released from primary cerebellar cultures.

An HPLC method is described that measures amino acids (putative neurotransmitters and/or neuromodulators) released from primary, dissociated cerebellar cells maintained in monolayer culture. Precolumn derivatization with phenylisothiocyanate, followed by reverse phase chromatography with UV detection was used to quantitate the phenylcarbamyl amino acid derivatives in a chemically defined medium. Quantitation was linear, reproducible and sensitive to one picomole. This method is useful for the measurement of putative neurotransmitters GABA, glutamate, aspartate, taurine and adenosine, and can easily be modified to analyze other amino acids in physiological samples.

[Angiosarcoma of the breast. Apropos of 8 cases and review of the literature]. / Les angiosarcomes du sein. Etude de 8 cas et revue de la littérature.

The 8 cases of primary breast angiosarcoma which were diagnosed, treated and had their follow-up at the Gustave-Roussy Institute between 1954 and 1995 are reported. The age at presentation ranged from 32 to 68 years. In 4 patients the vascular nature of their mammary lesion was conspicuous by a violaceous discolorations of the overlying skin. No patient had enlarged ipsilateral axillary lymph nodes. One patient had metastases. In 2 out of 5 patients who had a partial surgical or fine-needle biopsy before treatment, the diagnosis was missed, and adequate treatment was unduly delayed. The tumor most often presents as an ill defined area made of dense endothelium-lined papillae. A remarkable picture of "soap bubbles" has been identified in 4 cases. The "meshes" of fatty areas appear to be reinforced as they are infiltrated by tumor cells. This appearance may be specific of mammary angiosarcoma. By the French Cancer Centers' grading system for soft tissue sarcomas in general, grade is III in 3 tumors, II in 2 tumors, I in 3 tumors. Five tumors were treated by total mastectomy only. In 3 cases a total mastectomy was followed by radiation therapy to the chest wall. At diagnosis a chemotherapy was administered only to the patient who had metastases. Median disease-free survival was 9 months. Median overall survival was 13 months. From a review of the literature a simple mastectomy appears to be necessary as well as enough for local treatment. Patients with a grade III angiosarcoma of the breast should be included into a therapeutical trial of adjuvant chemotherapy for soft tissue sarcomas in general.

[The return of the prodigal child or allergy to ficus]. / Le retour de l'enfant prodigue ou l'allergie au ficus.

Ficus benjamina (FB), the weeping fig, belonging to the Moracea family, is now widely used as an indoor ornamental plant in houses and offices. Its latex can be responsible of IgE allergies : rhinoconjunctivitis, asthma, angiooedema, pruritus, anaphylactic shock. In some occupations such as gardeners, caretakers of plants, it can induce a contact urticaria. Most of these patients are atopics. We describe a case of non-occupational, indoor related rhinoconjunctivitis in a non-atopic patient. Prick-test and RAST to FB latex were positive and removal of the ficus plant resolved their symptoms confirming the etiologic role of the plant. The patient did not demonstrate sensitization to other common allergens (except weeds) involved in respiratory (latex of Hevea brasiliensis, mites...) and food allergies (negativity of the prick-tests for fig, avocado, banana, kiwi). Now, FB is a new hidden allergen in the house. Questionning for its presence and testing it should be considered; as it should be introduced in the standard prick-test panel.

Criminals' explanations of their criminal behavior, III: the effects of time and context.

The authors looked at the explanations for their index of violent crimes as given by 69 incarcerated violent male offenders, respectively. We then examined the extent to which those explanations changed with the passing of time and with change in context. We found that explanations of impaired internal control increased with the passing of time, and that such explanation was given more often to mental health professionals rather than law enforcement professionals. Finally, we found that our subjects tended to give mental health professionals fewer explanations involving external control with the passing of time.

[Large granular T-cell lymphocytic leukemia disclosed by bilateral uveitis: association with celiac disease]. / Leucémie à grands lymphocytes granuleux T révélée par une uvéite bilatérale: association à une maladie coeliaque.

A 70-year-old woman presented with bilateral anterior uveitis. She was on a gluten-free diet because of a celiac disease which had been diagnosed 3 months before. An anterior chamber aspirate contained a majority of large granular lymphocytes (LGL). The investigation of a chronic neutropenia led to the diagnosis of an otherwise typical T-LGL leukemia. This seems to be the first report of a CD3+ CD4- CD8+ T-LGL leukemia causing anterior uveitis through infiltration of leukemic cells, and the second report of an intriguing association of celiac disease with T-LGL leukemia.

[Modulation of 5-fluorouracil with folinic acid in advanced colorectal cancers. Groupe d'étude et de recherche sur les cancers de l'ovaire et digestifs (GERCOD)]. / La modulation du 5-fluorouracile par l'acide folinique dans les cancers colorectaux avancés. Groupe d'étude et de recherche sur les cancers de l'ovaire et digestifs (GERCOD).

The rational of leucovorin modulation of 5-fluorouracil and the clinical results in colorectal cancer are reviewed with special emphasis on the monthly schedule of low dose leucovorin and 5FU bolus for 5 consecutive days (NCCTG-Mayo Clinic regimen) and the bimonthly schedule of high-dose leucovorin and 5FU bolus plus continuous infusion for two consecutive days (LV5FU2) which is now considered as a new standard.

[Long term survival in metastatic colorectal cancer treated with leucovorin and 5-fluoro-uracil chemotherapy]. / Survie à long terme des cancers colorectaux métastatiques sous chimiothérapie par 5-fluoro-uracile.

PURPOSE: Median survival in advanced colorectal cancer patients treated with 5-fluoro-uracil (5FU) and leucovorin (LV) is between 12 and 18 months. The aim of this study was to evaluate long term survival in this disease. METHODS: We report here, retrospectively, the survival of 445 patients who entered in first-line prospective studies with LV-5FU-based regimen chemotherapy, between 1985 and 1995. RESULTS: Median survival was 18 months. The 3, 5 and 10 year survival were respectively 17.9%, 4.5% and 2.4%. Seventy-five patients survived more than 3 years, among them, 10 achieved a complete and 34 a partial response, 12 had curative liver or lung surgery. Fifteen patients lived more than 5 years, 2 achieved a complete and 7 a partial response. Seven had curative surgery. Eleven patients were still alive in 2002, among them 7 in complete remission at 5 years, including 3 who did not have surgery. CONCLUSION: This study shows that some patients with metastatic colorectal cancer can achieve long survival, especially when secondary curative surgery can be performed. However, 1% of the patients can be cured with LV-5FU chemotherapy alone. These results will be probably improve with the use of the new drugs: oxaliplatin and irinotecan.

[Oxaliplatin, folinic acid and 5-fluorouracil (folfox) in pretreated patients with metastatic advanced cancer. The GERCOD]. / Oxaliplatine, acide folinique et 5-fluorouracile (folfox) en seconde ligne thérapeutique du cancer colorectal métastasé. Le GERCOD.

Preliminary studies suggest synergy between oxaliplatin and fluorouracil (5-FU). To assess this issue, we performed a study in pretreated patients with advanced colorectal cancer (CRC) resistant to leucovorin and 5-FU. Regimen consisted of oxaliplatin day 1, 130 mg/m2 every two cycles (folfox 1) or 100 mg/m2/cycle (folfox 2) or 85 mg/m2/cycle (folfox 3) and leucovorin 500 mg/m2 as a 2-hour infusion, followed by 5-FU 22 h infusion 1.5-2 g/m2 for two consecutive days every 2 weeks. One hundred and thirteen patients have been treated. One complete response (CR) and 32 partial responses (PRs) were observed for an overall response rate of 29.2%. Sixty-seven patients had prior documented progression while receiving the same schedule of leucovorin and 5-FU than the one used in the folfox regimens, among them 18 had PRs (26.9%). The best response rate was observed in patients treated with the folfox 2 regimen: 41.7%. From start of folfox, median progression-free survival was 6 months and median survival 13 months. Limiting toxicities were peripheral neuropathy and neutropenia. Fifty-four percent of the patients experienced WHO toxicity > or = grade 3 with the folfox1 regimen, 45% with the folfox2 and 40% with the folfox3. The folfox regimens achieve a high response rate in pretreated patients with CRC. Further studies are needed to determine the best oxaliplatin dose-intensity.

[Locoregional recurrences of breast cancer]. / Récidives loco-régionales de cancers du sein.

AIM OF THE STUDY: To determine the characteristics of 51 cases of isolated local regional breast cancer recurrence. METHODS: Retrospective study from 1980 to 1992, survival calculated according to Kaplan-Meier and log-rank test. RESULTS: Twenty-five patients had had a conservative treatment of her primary tumour, 26 had been treated by modified radical mastectomy. Local regional recurrence rate was 9%: 44% of recurrences after lumpectomy and 43% of recurrences after mastectomy occurred within 2 years after the initial treatment. Site of local regional recurrence was chest wall only (16 cases), breast only (15 cases) or axillary or supraclavicular node with or without chest wall or breast involvement (20 cases). The actuarial 5-year survival rate after recurrence is 54%. It depends on the time to recurrence (40% if time to recurrence was less than 2 years, 68% if more than 2 years, p < 0.10), on initial node involvement (36% for N+, 71% for N-, p < 0.15) and on the site of recurrence (chest wall: 43%; breast: 48%; regional node: 12%, p < 0.10). CONCLUSION: Like in the literature, severe recurrences are early recurrences, lymph node recurrences and recurrences following a primary tumour with involved axillary nodes.

Kappa B-specific DNA binding proteins are differentially inhibited by enhancer mutations and biological oxidation.

Kappa B (kappa B) enhancer binding proteins isolated from the nuclei of activated human T cells produce two distinct nucleoprotein complexes when incubated with the kappa B element from the interleukin-2 receptor-alpha (IL-2R alpha) gene. These two DNA-protein complexes are composed of at least four host proteins (p50, p55, p75, p85), each of which shares structural similarity with the v-rel oncogene product. Nuclear expression of these proteins is induced with distinctly biphasic kinetics following phorbol ester activation of T cells (p55/p75 early and p50/p85 late). DNA-protein crosslinking studies have revealed that the more rapidly migrating B2 complex contains both p50 and p55 while the more slowly migrating B1 complex is composed of p50, p55, p75, and p85. Site-directed mutagenesis of the wild-type IL-2R alpha kappa B enhancer (GGGGAATCTCCC) has revealed that the binding of p50 and p55 (B2 complex) is particularly sensitive to alteration of the 5' triplet of deoxyguanosine residues. In contrast, formation of the B1 complex, reflecting the binding of p75 and p85, critically depends upon the more 3' sequences of this enhancer element. DNA binding by all four of these Rel-related factors is blocked by selective chemical modification of lysine and arginine residues, suggesting that both of these basic amino acids are required for binding to the kappa B element. Similarly, covalent modification of free sulfhydryl groups with diamide (reversible) or N-ethylmaleimide (irreversible) results in a complete loss of DNA binding activity. In contrast, mild oxidation with glucose oxidase selectively inhibits p75 and p85 binding while not blocking p50 and p55 interactions. These findings suggest that reduced cysteine thiols play an important role in the DNA binding activity of this family of Rel-related transcription factors.