Activated Carbon Modifications for Heterogeneous Fenton-Like Catalysis.

The effective and efficient degradation of persistent, recalcitrant pollutants by advanced oxidation processes is vital to both reduce hazardous waste and remediate polluted waters. One such advanced oxidation process is the use of Fenton chemistry, which can be optimized using heterogeneous catalysts. However, to make this AOP viable over conventional treatment methods, the technology needs to be optimized from both a technical and economic standpoint. From a heterogeneous catalyst optimization perspective, varying the surface chemistry of activated carbon and impregnating or doping with Fenton-like catalytic nanomaterials removes precipitation complications associated with traditional iron species in Fenton chemistry while generating effective amounts of highly oxidative hydroxyl radicals. Utilizing various techniques to synthesize heterogeneous catalysts with activated carbon as a backbone, in the presence of H2O2 the formation of hydroxyl radicals and removal of benzoic acid is tested. Comparing various additives, raw activated carbon impregnated with 5% MnO2 in the presence of H2O2 realized a high concentration of hydroxyl radical formation while maintaining low cost and relative ease of synthesis. This AC-Mn5 catalyst performed effectively in varying concentrations of H2O2, utilizing various synthesis techniques, after simulated aging of the catalyst structure, and over a wide pH range with the highest radical formation at acidic pH values. Utilizing this catalytic material as a substitute for iron species associated with traditional Fenton technology, the goal of designing a full set of oxidation functions towards persistent, recalcitrant pollutant removal while maintaining cost-effectiveness and scalability is proposed. It is anticipated these catalytic materials are effective to eliminate analogous contaminants and mixtures.

Incidence and Treatment of Arterial Access Dissections Occurring during Cardiac Catheterization.

BACKGROUND: Arterial access dissections may complicate cardiac catheterization and can often be treated percutaneously. The goal of this study was to examine the incidence, consequences, and the treatment of arterial access dissections at a tertiary referral hospital with an active training program. METHODS: Patients experiencing arterial access dissection during coronary angiography or intervention at our institution between October 1, 2004, and January 31, 2007, were identified and their records were retrospectively reviewed. RESULTS: Thirteen of the 3,062 consecutive patients (0.42%) had arterial access dissection during the study period. The location of the dissection was in the common femoral artery (CFA) (n = 6), the external iliac artery (EIA) (n = 6), or in an aortobifemoral graft (n = 1). Three of the six patients with CFA dissection were diagnosed during coronary angiography, and because of significant comorbidities were treated with self-expanding stents. After a mean follow-up of 7 months, they experienced no stent fracture or other complication. Six patients had EIA dissections. In one such patient, the dissection was not flow limiting and was treated conservatively. The remaining five patients underwent successful implantation of self-expanding stents, and during a mean follow-up of 9.6 months, no patient had any symptoms or events related to lower extremity ischemia. Finally, one patient had an aortobifemoral graft dissection. Due to the patient's critical condition, secondary to sepsis, his family elected to withdraw care, and he subsequently expired. CONCLUSIONS: Arterial access dissections occur infrequently during cardiac catheterization. Routine femoral artery angiography may help identify vascular access complications, often allowing simultaneous endovascular treatment, with excellent short-term outcomes.

Risk of noncardiac surgery after coronary drug-eluting stent implantation.

We examined the records of 38 patients who underwent 41 major and 18 minor noncardiac surgeries after successful drug-eluting stent (DES) implantation (57% sirolimus-eluting stents and 43% paclitaxel-eluting stents) at the Dallas Veterans Affairs Medical Center from April 2003 to January 2006. The mean patient age was 62 +/- 9 years, and all patients were men. A total of 41 major noncardiac surgeries (34% abdominal, 22% vascular, 17% genitourinary, and 27% other) were performed in 28 patients a median of 260 days after DES implantation. Also, 18 minor noncardiac surgeries (44% skin surgery, 44% injections, and 12% other) were performed in 10 patients a median of 297 days after DES implantation. No major adverse cardiac events or death occurred during or after the 41 major (0%, 95% confidence interval 0% to 9%) and 18 minor noncardiac (0%, 95% confidence interval 0% to 19%) surgeries. In conclusion, although our data were limited by the small sample size, they suggest a low risk of major cardiac complications in patients undergoing noncardiac surgery after coronary DES implantation.

Pain intolerance in opioid-maintained former opiate addicts: effect of long-acting maintenance agent.

Patients on methadone maintenance therapy are relatively intolerant of pain, a finding hypothesized to reflect a hyperalgesic state induced by chronic opioid administration. To explore if the intrinsic activity of the opioid maintenance agent might affect expression of hyperalgesia in this population, withdrawal latency for cold-pressor (CP) pain was compared between small groups of methadone-maintained (n = 18), buprenorphine-maintained (n = 18), and matched control (n = 18) subjects. The opioid-maintained groups had equal and significantly shorter withdrawal latencies than controls, however it is possible that high rates of continued illicit opioid use precluded finding differences between methadone and buprenorphine groups. Differential effects of maintenance agent were found for the few subjects without illicit opioid use, such that withdrawal latencies for methadone-maintained (n = 5) were less than for buprenorphine-maintained (n = 7) which were less than controls (n = 18). Diminished pain tolerance in patients receiving opioid maintenance treatment has significant clinical implications. More research is needed to determine if buprenorphine offers advantages over methadone in this regard.

Improvement of HbA1c without increased hypoglycemia in adolescents and young adults with type 1 diabetes mellitus treated with recombinant human insulin-like growth factor-I and insulin. rhIGF-I in IDDM Study Group.

OBJECTIVE: A 12-week trial with insulin and rhIGF-I compared to insulin and placebo was conducted in patients with type 1 diabetes mellitus aged 11-66 years. We present the efficacy and safety data pertinent to the younger subset of participants (11-21 years). STUDY DESIGN: The patients were randomized to receive s.c. insulin and either placebo or rhIGF-I at one of the following doses (microg/kg): 40 a.m./40 p.m., 80 a.m./40 p.m. or 80 a.m./60 p.m.). RESULTS: The average decrease of HbA1c from baseline was higher (-1.3 +/- 0.2%) in the rhIGF-I treated group compared to the placebo group (-0.6 +/- 0.3%; p <0.05). This was associated with a significant decrease in daily insulin dose (U) of both Regular (rhIGF-I: -7 +/- 1; placebo: -1 +/- 1; p <0.01) and NPH (rhIGF-I: -4 +/- 2; placebo: +5 +/- 3; p <0.05). The incidence of hypoglycemia and weight gain were not increased. Edema, jaw pain and tachycardia were associated with rhIGF-I treatment, particularly at doses higher than 40 microg/kg b.i.d. Dose-related early worsening of retinopathy was observed in 11/55 patients in the rhIGF-I group, with resolution in the majority of them in the follow-up photographs. CONCLUSIONS: These findings suggest a possible role for rhIGF-I co-therapy in adolescents and young adults with type 1 diabetes mellitus.

Pain responses in methadone-maintained opioid abusers.

Providing pain management for known opioid abusers is a challenging clinical task, in part because little is known about their pain experience and analgesic requirements. This study was designed to describe pain tolerance and analgesic response in a sample of opioid addicts stabilized in methadone-maintenance (MM) treatment (n = 60) in comparison to matched nondependent control subjects (n = 60). By using a placebo-controlled, two-way factorial design, tolerance to cold-pressor (CP) pain was examined, both before and after oral administration of therapeutic doses of common opioid (hydromorphone 2 mg) and nonsteroidal anti-inflammatory (ketorolac 10 mg) analgesic agents. Results showed that MM individuals were significantly less tolerant of CP pain than control subjects, replicating previous work. Analgesic effects were significant neither for medication nor group. These data indicate that MM opioid abusers represent a pain-intolerant subset of clinical patients. Their complaints of pain should be evaluated seriously and managed aggressively.

Perceptual reactance, drug preference, and electrodermal activity in treatment-seeking substance abusers.

Perceptual reactance (PR) was explored as a contributing variable to drug abuse. PR is defined as the general tendency of an individual's central nervous system to perceptually modulate incoming sensory stimuli. Using an adaptive model of drug use, it was hypothesized that drug preference in substance abusers would vary with PR. Specifically, perceptual reducers, who subjectively dampen afferent sensation, would prefer experience-expanding drugs (i.e., cocaine and amphetamines) to heighten perception. Conversely, perceptual augmenters would prefer sensory-restricting drugs (i.e., opioids and sedative-hypnotics) that attenuate or modulate environmental stimuli. Utilizing subjective (Reducing-Augmenting Scale) and objective (electrodermal responses) measures of PR, the relationship was tested in a sample of treatment-seeking substance abusers (n = 122). The sample was stratified on whether or not they were abstinent. Interestingly, a higher than anticipated rate of electrodermal non-responsivity was found across the sample and the implications of this finding are discussed. The study hypothesis was only supported in the electrodermally-responsive group.

Cotherapy with recombinant human insulin-like growth factor I and insulin improves glycemic control in type 1 diabetes. RhIGF-I in IDDM Study Group.

OBJECTIVE: To study the effects of 12 weeks of cotherapy with recombinant human IGF-I (rhIGF-I) and insulin on glycemic control in patients with type 1 diabetes. RESEARCH DESIGN AND METHODS: The study population consisted of 223 patients who ranged in age from 11-66 years and were randomized in a double-blind study to receive 12 weeks of treatment with twice-daily subcutaneous injections of placebo (n = 54), or rhIGF-I at a dose (A.M/P.M) of 40/40 micrograms/kg (n = 56), 80/40 micrograms/kg (n = 57), or 80/60 micrograms/kg (n = 56), while continuing to receive standard insulin therapy. Patients were instructed to test blood glucose levels four times daily and adjust insulin doses to optimize blood glucose control. HbAlc, insulin requirements, body weight, and parameters of the IGF-IGF-binding protein axis were assessed before and during treatment. RESULTS: All groups were comparable at baseline with respect to mean age, gender distribution, duration of diabetes, HbAlc, and BMI. Cotherapy with rhIGF-I/insulin produced a mean decrease in HbAlc of 1.2%, compared with a 0.7% decrease in HbAlc for patients receiving intensified insulin therapy alone (P < or = 0.01). Subjects receiving rhIGF-I/insulin cotherapy also decreased their daily insulin usage by 11-19%, compared with a 7% increase in insulin usage reported by the placebo group. Moreover, the incidence of hypoglycemia was similar in subjects treated with rhIGF-I/Insulin cotherapy compared with those treated with insulin alone, despite the better glycemic control of the former group. The 40/40 dose of rhIGF-I was well tolerated. Higher doses of rhIGF-I did not further improve efficacy yet were associated with unacceptable levels of adverse events, including edema, jaw pain, and early worsening of retinopathy. CONCLUSIONS: These results demonstrate that rhIGF/insulin cotherapy improves glycemic control in patients with type 1 diabetes better than optimized insulin management alone; longer-term trials would be required to determine an acceptable benefit-risk profile.

Motivational interviewing: an effective brief intervention for alcohol and drug abuse patients.

Inadequate motivation is a crucial factor for the substance abuser's inability to change harmful behavior. Although not widely implemented in advanced nursing practice, the motivational interviewing strategies have great utility in interactions with substance abuse patients in primary care settings. This article provides implementation strategies for an effective independent nursing intervention that can be utilized to manage drug and alcohol abuse behaviors.

Behavior change after growth hormone treatment of children with short stature.

OBJECTIVES: To measure the prevalence of behavioral and learning problems among children with short stature and to assess the effect of growth hormone (GH) treatment on such problems. STUDY DESIGN: A total of 195 children with short stature (age range 5 to 16 years, mean age 11.2 years) were tested for intelligence, academic achievement, social competence, and behavior problems before beginning GH therapy and yearly during 3 years of treatment. Children were classified as having growth hormone deficiency (GHD) when GH responses to provocative stimuli were <10 ng/mL (n = 109) and as having idiopathic short stature (ISS) when >10 ng/mL (n = 86). A normal-statured matched comparison group was tested at the baseline only. RESULTS: Seventy-two children in the GHD group and 59 children in the ISS group completed 3 years of GH therapy and psychometric testing. Mean IQs of the children with short stature were near average. IQs and achievement scores did not change with GH therapy. Child Behavior Checklist scores for total behavior problems were higher (P < .001) in the children with short stature than in the normal-statured children. After 3 years of GH therapy these scores were improved in patients with GHD (P < .001) and ISS (P < .003). Also, there was improvement in the scores of children in the GHD group in the internalizing subscales (withdrawn: P < .007; somatic complications, P < .001; anxious/depressed, P < .001) and on the 3 components of the ungrouped subscales (attention, social problems, and thought problems, each P = .001). Larger effects were observed in the GHD group than in the ISS group. CONCLUSIONS: Many referred children with short stature have problems in behavior, some of which ameliorate during treatment with GH.

Pain tolerance in opioid addicts on and off naltrexone pharmacotherapy: a pilot study.

Under certain experimental and clinical conditions, opioid antagonists have been demonstrated to have analgesic properties. In this open-label, nonrandomized, within-subject comparison, the effect of chronic treatment with the antagonist, naltrexone, on tolerance for experimental pain was evaluated in a small sample of male opioid addicts (N = 10) receiving naltrexone maintenance. Cold-pressor pain tolerance was measured during (> or = 6 weeks) and after discontinuation (> or = 1 week) of naltrexone treatment. Intra-subject comparison revealed that eight of the ten subjects were more pain tolerant (median + 20 sec) while receiving naltrexone. It is suggested that either midbrain opioid system upregulation in the presence of naltrexone or underlying individual differences in pain tolerance in persons with addictive disease provide potential explanations for these findings.

How much insulin-like growth factor I (IGF-I) circulates? Impact of standardization on IGF-I assay accuracy.

There is a significant systematic difference between the normal range obtained from ethylenediamine tetraacetate plasma samples using the Genentech total insulin-like growth factor I (IGF-I) RIA and normal ranges for other total IGF-I RIAs. To determine whether the quality of the assay standard was the cause of this systematic difference, we analyzed commercially available preparations of recombinant human IGF-I (rhIGF-I) typical of those used as IGF-I immunoassay standards along with our own well characterized rhIGF-I assay standard. For the commercial standards, high performance liquid chromatography-derived purities were low, and some vendor-assigned protein concentrations were inconsistent with values from quantitative amino acid analysis. The Genentech rhIGF-I assay standard was highly pure and quantitatively correct. However, the poor quality of some commercial rhIGF-I preparations was not the primary reason for the systematic discrepancy between the Genentech total IGF-I RIA normal range and most other normal ranges. Most assays for total IGF-I are calibrated against the WHO International Reference Reagent (IRR) for IGF-I Immunoassays (87/518). The Genentech total IGF-I RIA is not calibrated against WHO IRR 87/518. The protein content assigned to WHO IRR 87/518 was a consensus value from a multicenter collaborative study. Physicochemical analyses showed that WHO IRR 87/518 is Met(-1)-IGF-I of low purity (44%), and that the assigned protein content is higher than the value determined by quantitative amino acid analysis. Thus, assays that are calibrated against WHO IRR 87/518 will report total IGF-I concentrations in excess of actual values. We believe that calibration against WHO IRR 87/518 is the cause of the systematic discrepancy between the Genentech IGF-I assay normal range and most other normal ranges, and that much of the plasma IGF-I concentration data in the literature are of questionable accuracy.

Screening for addiction in patients with chronic pain and "problematic" substance use: evaluation of a pilot assessment tool.

Assessing for the presence of addiction in the chronic pain patient receiving chronic opioid analgesia is a challenging clinical task. This paper presents a recently developed screening tool for addictive disease in chronic pain patients, and pilot efficacy data describing its ability to do so. In a small sample of patients (n = 52) referred from a multidisciplinary pain center for "problematic" medication use, responses to the screening questionnaire were compared between patients who met combined diagnostic criteria for a substance use disorder and those who did not, as assessed by a trained addiction medicine specialist. Responses of addicted patients significantly differed from those of nonaddicted patients on multiple screening items, with the two groups easily differentiated by total questionnaire score. Further, three key screening indicators were identified as excellent predictors for the presence of addictive disease in this sample of chronic pain patients.

Applications of abduction: hypothesis testing of neuroendocrinological qualitative compartmental models.

It is difficult to assess hypothetical models in poorly measured domains such as neuroendocrinology. Without a large library of observations to constrain inference, the execution of such incomplete models implies making assumptions. Mutually exclusive assumptions must be kept in separate worlds. We define a general abductive multiple-worlds engine that assesses such models by (i) generating the worlds and (ii) tests if these worlds contain known behaviour. World generation is constrained via the use of relevant envisionment. We describe QCM, a modeling language for compartmental models that can be processed by this inference engine. This tool has been used to find faults in theories published in international refereed journals; i.e. QCM can detect faults which are invisible to other methods. The generality and computational limits of this approach are discussed. In short, this approach is applicable to any representation that can be compiled into an and-or graph, provided the graphs are not too big or too intricate (fanout < 7).