bluuebunny/crossref_metadata_2025 huggingface dataset:
Patients' perspectives on taking warfarin: qualitative study in family practice
Authors: Dantas Guilherme Coelho , Thompson Barbara V , Manson Judith A , Tracy C Shawn , Upshur Ross EG
Published: July 2004

Background

Despite the well-documented benefits of using warfarin to prevent stroke, physicians remain reluctant to initiate therapy, and especially so with the elderly owing to the higher risk of hemorrhage. Prior research suggests that patients are more accepting of the risk of bleeding than are physicians, although there have been few qualitative studies. The aim of this study was to employ qualitative methods to investigate the experience and perspective of individuals taking warfarin.

Methods

We conducted face-to-face interviews with 21 older patients (12 male, 9 female) who had been taking warfarin for a minimum of six months. Participants were patients at a family practice clinic situated in a large, tertiary care teaching hospital. We used a semistructured interview guide with four main thematic areas: decision-making, knowledge/education, impact, and satisfaction. Data were analysed according to the principles of content analysis.

Results and Discussion

Participants tended to have minimal input into the decision to initiate warfarin therapy, instead relying in great part on physicians' expertise. There appeared to be low retention of information received regarding the therapy; half the patients in our sample possessed only a superficial level of understanding of the risks and benefits. This notwithstanding, participants reported a high level of satisfaction with the care provided and a low level of impact on their day-to-day lives.

Conclusions

Minimal patient involvement in the initial decision and modest knowledge did not appear to diminish satisfaction with warfarin management. At the same time, care providers exert a tremendous influence on the initiation of warfarin therapy and should strive to incorporate patient preferences and expectations into the decision-making process.
Detection of a novel sense–antisense RNA-hybrid structure by RACE experiments on endogenous troponin I antisense RNA
Authors: BARTSCH HOLGER , VOIGTSBERGER STEFANIE , BAUMANN GERT , MORANO INGO , LUTHER HANS PETER
Published: July 2004

Conformational changes in the troponin/tropomyosin complex significantly alter the mechanical properties of cardiac muscle. Phosphorylation of cardiac troponin I, part of the troponin/tropomyosin complex, reduces calcium affinity, which leads to increased relaxation of cardiac muscle. Because cardiac troponin I plays a central role in tuning the heart to different work demands, detailed knowledge of troponin I protein regulation is required. Our group previously detected naturally occurring antisense RNA for troponin I in human and rat hearts, and here, attempt to unravel the structure of rat cardiac troponin I antisense RNA. We performed rapid amplification of cDNA ends (RACE) experiments and discovered antisense sequences identical to a copy of the sense mRNA, which led us to conclude that the antisense RNA must be transcribed from troponin I mRNA in the cytoplasm. Moreover, we isolated RNA structures comprising sense and antisense sequences in one continuous molecule. As we found no homolog structures described in the literature, we called this “hybrid RNA.” Because a duplex formation was demonstrated previously we concluded that hybrid RNA is a consequence of a tight interaction between sense and antisense troponin I RNA in vivo, which we discuss in the article.
New tertiary constraints between the RNA components of active yeast spliceosomes: A photo-crosslinking study
Authors: RYAN DANIEL E. , KIM CHANG HEE , MURRAY JAMES B. , ADAMS CHRIS J. , STOCKLEY PETER G. , ABELSON JOHN
Published: July 2004

Elucidation of the three-dimensional (3D) structures of the two sequential active sites in spliceosomes is essential for understanding the mechanism of premessenger RNA splicing. The mechanism is predicted to be catalyzed by the small nuclear RNA (snRNA) components of spliceosomes. To obtain new tertiary constraints between the RNA components, we produced and mapped crosslinks between U6 snRNA and the proximal RNAs of active yeast spliceosomes (“yeast“ in this report is Saccharomyces cerevisiae). Thus, specific sites in U6, when substituted with a photoreactive 4-thiouridine or 5-iodouridine, produced spliceosome-dependent crosslinks to U2 snRNA, or in one case, to the pre-mRNA substrate. One set of U2–U6 crosslinks formed before the Prp2p-dependent step of spliceosome assembly, whereas another set formed during or after this step but before the first chemical step of splicing. This latter set of crosslinks formed across U2–U6 helix I. Importantly, this set provides new tertiary constraints for developing 3D models of fully assembled yeast spliceosomes, which are poised for the first chemical step of splicing.
In vivo selection reveals combinatorial controls that define a critical exon in the spinal muscular atrophy genes
Authors: SINGH NATALIA N. , ANDROPHY ELLIOT J. , SINGH RAVINDRA N.
Published: July 2004

Humans have two near identical copies of the survival of motor neuron (SMN) gene, SMN1 and SMN2. In spinal muscular atrophy (SMA), SMN2 is not able to compensate for the loss of SMN1 due to an inhibitory mutation at position 6 (C6U mutation in transcript) of exon 7. We have recently shown that C6U creates an extended inhibitory context (Exinct) that causes skipping of exon 7 in SMN2. Previous studies have shown that an exonic splicing enhancer associated with Tra2 (Tra2-ESE) is required for exon 7 inclusion in both SMN1 and SMN2. Here we describe the method of in vivo selection that determined the position-specific role of wild-type nucleotides within the entire exon 7. Our results confirmed the existence of Exinct and revealed the presence of an additional inhibitory tract (3′-Cluster) near the 3′-end of exon 7. We also demonstrate that a single nucleotide substitution at the last position of exon 7 improves the 5′ splice site (ss) such that the presence of inhibitory elements (Exinct as well as the 3′-Cluster) and the absence of Tra2-ESE no longer determined exon 7 usage. Our results suggest that the evolutionary conserved weak 5′ ss may serve as a mechanism to regulate exon 7 splicing under different physiological contexts. This is the first report in which a functional selection method has been applied to analyze the entire exon. This method offers unparallel advantage for determining the relative strength of splice sites, as well as for identifying the novel exonic cis-elements.
Using an RNA secondary structure partition function to determine confidence in base pairs predicted by free energy minimization
Authors: MATHEWS DAVID H.
Published: July 2004

A partition function calculation for RNA secondary structure is presented that uses a current set of nearest neighbor parameters for conformational free energy at 37°C, including coaxial stacking. For a diverse database of RNA sequences, base pairs in the predicted minimum free energy structure that are predicted by the partition function to have high base pairing probability have a significantly higher positive predictive value for known base pairs. For example, the average positive predictive value, 65.8%, is increased to 91.0% when only base pairs with probability of 0.99 or above are considered. The quality of base pair predictions can also be increased by the addition of experimentally determined constraints, including enzymatic cleavage, flavin mono-nucleotide cleavage, and chemical modification. Predicted secondary structures can be color annotated to demonstrate pairs with high probability that are therefore well determined as compared to base pairs with lower probability of pairing.
Trinitarian Theology and the Politics of Nature
Authors: Scott Peter Manley
Published: July 2004

This article argues that Christian theology of nature faces two central questions: (1) when engaging the modern concept of nature, should theology accept the modern concept or seek to undermine it? (2) Given that the reality of nature is various and must include some account of the politics of the concept, how should theology engage with such politics? It is argued that a Christian, trinitarian theology of nature should be developed by, first, ‘ecologising’ its notion of nature; and, second, by seeking to overcome in dialectical fashion the modern concept of nature in favour of a notion of creatureliness that is both natural and political.
Electing to do Ecotheology
Authors: Pearson Clive
Published: July 2004

The discipline of ecotheology is relatively new. It can be practised in a variety of ways. There is no consensus about how and what should be taught. This article explores the underlying assumptions, method and content of one such course taught as an elective under the umbrella of a systematic theology. It demonstrates the need to balance a global discourse with the particular ecology of where the course is taught.
Fixed‐Dose Vasopressin Compared with Titrated Dopamine and Norepinephrine as Initial Vasopressor Therapy for Septic Shock
Authors: Hall Lisa G. , Oyen Lance J. , Taner C. Burcin , Cullinane Daniel C. , Baird Thomas K. , Cha Stephen S. , Sawyer Mark D.
Published: July 2004

Study Objective. To investigate the early blood pressure effects of vasopressin compared with titrated catecholamines as initial drug therapy in patients with septic shock.

Design. Retrospective cohort, single‐center study.

Setting. Intensive care units at the Mayo Clinic, Rochester, Minnesota.

Patients. Fifty, 49, and 51 intensive care patients treated initially with vasopressin, norepinephrine, and dopamine, respectively.

Intervention. Patients received either intravenous infusion of fixed‐dose vasopressin 0.04 U/minute or titrated infusions of norepinephrine or dopamine for low systemic arterial pressures.

Measurements and Main Results. Patients treated with vasopressin, norepinephrine, and dopamine were similar in all measured characteristics except for their score on the Acute Physiology and Chronic Health Evaluation (APACHE) III (dopamine > vasopressin, p=0.049), renal comorbidities (dopamine > vasopressin, p=0.03) and baseline mean arterial pressure (MAP) (norepinephrine < vasopressin, p=0.005 or dopamine < vasopressin, p=0.05). In all patients, MAP 1 hour before and 1 hour after intervention, heart rate, and systolic blood pressure were obtained. No treatment differences were identified in achieving postvasopressin MAP after adjusting for APACHE III score, renal dysfunction, and baseline MAP. In patients receiving vasopressin, 28‐day mortality was 52%, similar to those receiving norepinephrine (65%, p=0.28) and dopamine (60%, p=0.53).

Conclusion. Initial, fixed‐dose vasopressin infusions increased MAP to 70 mm Hg or greater at 1 hour in intensive care patients with septic shock, similar to titrated norepinephrine or dopamine. Fixed‐dose vasopressin appears appropriate as an alternative agent for hemodynamic support in patients with septic shock.
Role of Clopidogrel in Unstable Angina and Non—ST‐Segment Elevation Myocardial Infarction: From Literature and Guidelines to Practice
Authors: Kerr Jessica L. , Oppelt Thomas F. , Rowen Randall C.
Published: July 2004

Clinical trials are the backbone of treatment paradigm shifts and guideline development. In terms of acute coronary syndromes, the American College of Cardiology and the American Heart Association (ACC‐AHA) have developed extensive guidelines to assist the practitioner in the appropriate use of drugs including antiischemic, anticoagulant, and antiplatelet agents. Clopidogrel, an adenosine 5′‐diphosphate antagonist, is one such drug. Unfortunately, consensus guidelines are limited by the design of the clinical trials they reference. Clopidogrel trials have examined various outcomes in patients for a limited time frame, making longer term use of the drug difficult to justify. An ongoing study, estimated to be completed in 2005, is evaluating the long‐term use of clopidogrel in high‐risk patients. Aspirin, however, has become a lifelong therapy for many patients, based on clinical trials and medical experience. Patient‐specific risk factors, the drugs' safety profiles, and costs, in addition to the ACC‐AHA guidelines, must all be considered by clinicians when selecting the appropriate agent and its duration of use.
The Role of Vasopressin in Vasodilatory Septic Shock
Authors: Obritsch Marilee D. , Bestul Daniel J. , Jung Rose , Fish Douglas N. , MacLaren Robert
Published: July 2004

Septic shock that requires therapy with adrenergic agents is associated with high rates of mortality. Inappropriately normal or low serum concentrations of vasopressin contribute to the development of hypotension during sepsis. We critically evaluated the role of administering exogenous vasopressin to patients with septic shock. A computerized search of MEDLINE from January 1966–December 2003 and a manual search of relevant journals for abstracts were conducted. Eleven retrospective, six prospective cohort, and four prospective randomized studies were identified. Most studies evaluated short‐term infusions of vasopressin at 0.08 U/minute or less as add‐on therapy in patients requiring adrenergic agents. The results show that starting vasopressin in patients with septic shock increases systemic vascular resistance and arterial blood pressure, thus reducing the dosage requirements of adrenergic agents. These effects are rapid and sustained. Substantial enhancement of urine production, likely due to increased glomerular filtration rate, was shown in several studies. A few studies demonstrated clinically significant reduced cardiac output or cardiac index after vasopressin was begun, necessitating cautious use in patients with cardiac dysfunction. Vasopressin was associated with ischemia of the mesenteric mucosa, skin, and myocardium; elevated hepatic transaminase and bilirubin concentrations; hyponatremia; and thrombocytopenia. Limiting the dosage to 0.03 U/minute or less may minimize the development of these adverse effects. Vasopressin 0.03 U/minute or less should be considered if response to one or two adrenergic agents is inadequate or as a method to reduce the dosage of adrenergic agents. At present, vasopressin therapy should not be started as first‐line therapy. Additional studies are needed to determine the optimum dosage, duration, and place in therapy of vasopressin relative to adrenergic agents. A multicenter, comparative study of vasopressin 0.03 U/minute as add‐on therapy is under way and should provide mortality data.
Candida kefyr, an Uncommon but Emerging Fungal Pathogen: Report of Two Cases
Authors: Corpus Kimberly , Hegeman‐Dingle Rozelle , Bajjoka Iman
Published: July 2004

Although Candida species are present as normal microflora of the human host, alterations in host defenses can lead to development of disease. Candida infections, ranging from urinary tract infections to bloodstream infections, are common in patients in the intensive care unit. Infections with non‐albicans Candida sp are becoming more frequent, and resistance among these isolates is concerning. Candida kefyr is an uncommonly documented fungal pathogen. We report two cases of infection resulting from C. kefyr in our institution. The two patients had underlying disease states and drug therapies that increased the likelihood of developing an immunocompromised state. The C. kefyr isolates obtained from both patients were susceptible to amphotericin B, fluconazole, and itraconazole. Both patients had resolution of infection, one after receiving treatment with amphotericin B and the other with voriconazole.
Pharmacist‐Provided Anticoagulation Management in United States Hospitals: Death Rates, Length of Stay, Medicare Charges, Bleeding Complications, and Transfusions
Authors: Bond C. A. , Raehl Cynthia L.
Published: July 2004

We explored the associations between pharmacist‐provided anticoagulation management in hospitalized Medicare patients and several major heath care outcomes: death rate, length of stay, Medicare charges, bleeding complications, and transfusions. Using the 1995 National Clinical Pharmacy Services database and the 1995 Medicare database for hospitals, data were retrieved for 717,396 Medicare patients treated in 955 hospitals for conditions requiring anticoagulant therapy. In hospitals without pharmacist‐provided heparin management, death rates were 11.41% higher (χ2 (1) = 122.84, p<0.0001), length of stay was 10.05% higher (Mann‐Whitney U test = 40039529342, p<0.0001), Medicare charges were 6.60% higher (U = 41004749266, p<0.0001), bleeding complications were 3.1% higher (χ2 (1) = 10.996, p=0.0009) and the transfusion rate for bleeding complications was 5.47% higher (χ2 (1) = 11.24, p=0.0008) than in hospitals with pharmacist‐provided heparin management. In hospitals without pharmacist‐provided warfarin management, death rates were 6.20% higher (χ2 (1) = 19.20, p<0.0001), length of stay was 5.86% higher (U = 25730993838, p<0.0001), Medicare charges were 2.16% higher (U = 259955112970, p<0.0001), bleeding complications were 8.09% higher (χ2 (1) = 49.259, p<0.0001), and the transfusion rate for bleeding complications was 22.49% higher (χ2 (1) = 78.68, p<0.0001). Study hospitals without pharmacist‐provided heparin management had 4664 more deaths, 494,855 more patient‐days, 145 more patients with bleeding complications, and $651,274,844 more in patient charges; 9784 more units of whole blood were used in patients requiring transfusions for bleeding complications. Hospitals without pharmacist‐provided warfarin management had 2786 more deaths, 316,589 more patient‐days, 429 more patients with bleeding complications, and $234,275,490 more in patient charges; 8991 more units of whole blood were used in patients requiring transfusions for bleeding complications. The implications of these findings are significant for the health care system, especially considering that the study population represents 28.25% of hospitalized Medicare patients who should receive anticoagulants, and that total Medicare admissions represent 35.02% of total admissions to United States hospitals.
Effect of Tenofovir Disoproxil Fumarate on the Pharmacokinetics and Pharmacodynamics of Total, R‐, and S‐Methadone
Authors: Smith Patrick F. , Kearney Brian P. , Liaw Sandra , Cloen Denise , Bullock Julie M. , Haas Curtis E. , Yale Kitty , Booker Brent M. , Berenson Charles S. , Coakley Dion F. , Flaherty John F.
Published: July 2004

Study Objective. To evaluate the potential effect of tenofovir disoproxil fumarate (DF) on the pharmacokinetics of methadone.

Design. Phase I, open‐label, fixed‐sequence, pharmacokinetic drug‐drug interaction study.

Setting. Clinical research center.

Subjects. Fourteen volunteers receiving stable methadone maintenance therapy who were not infected with the human immunodeficiency virus.

Intervention. Tenofovir DF was added to the subjects' methadone regimens.

Measurements and Main Results. The pharmacokinetics of total, R‐, and S‐methadone were evaluated at baseline and after 2 weeks of daily tenofovir DF coadministration with a light meal. Steady‐state tenofovir DF pharmacokinetics were evaluated at day 15. Bioequivalence testing was conducted of total, R‐, and S‐methadone area under the serum or plasma concentration‐time curve during the 24‐hour dosing interval at steady state (AUCss) and maximum concentration in serum or plasma (Cmax). Subjects were evaluated for changes in methadone pharmacodynamics by the Short Opiate Withdrawal Scale (SOWS) and pupillary diameter measurements at frequent intervals. Coadministration with tenofovir DF did not affect the pharmacokinetics of methadone. Geometric mean R‐methadone systemic exposures, AUCss and Cmax, differed by 5% or less when methadone was dosed with tenofovir D F. Similar results were observed for S‐methadone and for total methadone. Both AUCss and Cmax met the strict criteria for bioequivalence between the two study periods for total, R‐, and S‐methadone, indicating a lack of drug interaction when tenofovir DF was coadministered with methadone. No significant changes in SOWS scores or pupillary diameter measurements occurred, and no notable clinical adverse events were reported.

Conclusion. Tenofovir DF pharmacokinetics were comparable to previously reported values of tenofovir DF in HIV‐infected patients. Coadministration of methadone with tenofovir DF did not alter the pharmacokinetics or pharmacodynamics of total, R‐, or S‐methadone. Tenofovir DF may be given as part of a once‐daily antiretroviral regimen in patients receiving methadone maintenance therapy.
Impact of Safety Warnings on Drug Utilization: Marketplace Life Span of Cisapride and Troglitazone
Authors: Wilkinson Julie J. , Force Rex W. , Cady Paul S.
Published: July 2004

Study Objective. To evaluate the impact of safety alerts on the volume of cisapride and troglitazone usage.

Design. Retrospective database analysis.

Setting. University research center.

Material. Idaho Medicaid claims data from January 1994–July 2000.

Measurements and Main Results. Monthly counts of total and new prescriptions filled for cisapride and troglitazone were analyzed graphically over time as a function of all prescriptions. New prescriptions were defined as those filled by patients who had not received the drug within the previous year. A binomial comparison of the 5 months before and after each safety alert was conducted by Poisson distribution. Overall and new cisapride usage increased after the first alert, which occurred in February 1995 (p<0.05). After the second alert, in September 1995, growth in new prescriptions ended but total prescriptions continued to grow (p<0.05). After the third alert, in June 1998, growth in total use ended and the number of new prescriptions declined (p<0.05). The final two alerts (June 1999 and January 2000) were met with significant declines (p<0.05 for both). Troglitazone was the subject of two alerts in October and December 1997. After these, overall usage increased (p<0.05), whereas the number of new prescriptions decreased (p<0.05). The third alert, in July 1998, caused no change as total prescription use continued to grow (p<0.05), whereas the number of new prescriptions decreased (p<0.05). A fourth alert, in June 1999, resulted in a decrease of overall usage and new prescriptions (p<0.05 for both).

Conclusion. Numerous safety alerts were required for each drug before drug usage declined. The decline in overall use was slower than the decline in new prescriptions, possibly indicating a need for increased assessment of refilled prescriptions after the release of new safety data.
Metformin Monitoring and Change in Serum Creatinine Levels in Patients Undergoing Radiologic Procedures Involving Administration of Intravenous Contrast Media
Authors: Parra David , Legreid Anna M. , Beckey Nick P. , Reyes Sonia
Published: July 2004

Study Objectives. To evaluate the prevalence and magnitude of serum creatinine level elevations in patients receiving metformin who underwent radiologic procedures involving administration of intravenous contrast media, and to evaluate the efficacy of an electronic consultation in promoting timely evaluation of renal function after the procedure.

Design. Retrospective evaluation.

Setting. Veterans Affairs Medical Center.

Patients. Ninety‐seven patients receiving metformin who underwent a radiologic procedure involving administration of intravenous contrast media over a 27‐month period.

Measurements and Main Results. Ninety‐seven patients underwent a total of 111 radiologic procedures with documented administration of intravenous contrast dye. Average time from procedure to laboratory follow‐up, excluding one patient, was 2.62 ± 1.56 days. Average serum creatinine levels before and after the procedure were 1.10 ± 0.19 and 1.13 ± 0.23 mg/dl, respectively (p>0.05). Four patients developed contrast material‐associated nephropathy. An additional four patients with borderline serum creatinine levels at baseline (1.4 mg/dl) had a serum creatinine level of 1.5 mg/dl or greater after the procedure.

Conclusion. Our results indicated that electronic consultations result in timely evaluation of serum creatinine levels in patients receiving metformin who undergo a radiologic procedure involving intravenous contrast material. Also, the study suggests that nearly 4% of patients with diabetes mellitus and normal renal function may develop contrast material–associated neuropathy with nonionic contrast material. In addition, about 8% of patients with diabetes treated with metformin (with baseline serum creatinine levels < 1.5 mg/dl) who undergo a procedure with nonionic intravenous contrast material acquire an increased risk (serum creatinine ≥ 1.5 mg/dl) of lactic acidosis. These findings support the recommendations of the Food and Drug Administration regarding metformin monitoring in patients undergoing radiologic procedures involving administration of intravenous contrast media.
Pharmacokinetics of Modified Oral Calcitonin Product in Healthy Volunteers
Authors: Chin Christine M. , Gutierrez Maria , Still J. Gordon , Kosutic Gordana
Published: July 2004

Study Objective. To assess the preliminary pharmacokinetics, pharmacodynamics, safety, and tolerability of single oral doses of a chemically modified salmon calcitonin product, CT‐025, in healthy volunteers.

Design. Phase I, exploratory, five‐way, open‐label, nonrandomized, crossover study.

Setting. Clinical research center.

Subjects. Twelve healthy volunteers aged 22–44 years.

Intervention. A single oral dose of CT‐025 was administered on 5 separate days with a 72‐hour washout period between doses. Each dose consisted of CT‐025 160 or 320 μg in varying relative concentrations of a mixture of excipients (formulations A, B, and C).

Measurements and Main Results. Serial blood samples were collected for determination of plasma CT‐025, total serum calcium, and ionized serum calcium concentrations during the 4‐hour period after dose administration. The data are the results from four of the five dosing days, when subjects received CT‐025 in high and low concentrations of excipients. The data indicate that CT‐025 was rapidly absorbed from the gastrointestinal tract. Mean peak plasma concentrations ranging from 51 ± 51–110 ± 59 pg/ml were observed 36–54 minutes after administration. Mean terminal elimination half‐lives ranged from 54–76 minutes. There was a trend for the mean maximum concentration and area under the plasma concentration‐time curve (AUC) from time zero to the time of the last quantifiable plasma concentration to increase with dose. Single oral doses of CT‐025 160 and 320 μg were pharmacologically active, inducing a statistically significant decrease in total and ionized serum calcium concentrations. The rate of decrease in ionized serum calcium concentration was significantly related to the CT‐025 dose. Single oral doses were well tolerated; some subjects experienced mild and transient nausea.

Conclusion. Single doses of CT‐025 were absorbed into the systemic circulation after oral administration and were well tolerated in healthy volunteers at doses up to 320 μg. These data suggest that oral delivery of salmon calcitonin becomes feasible with this product and support further clinical investigation of CT‐025 as a treatment for osteoporosis and osteoporotic bone pain.
Chemical Methods in Archaeology
Authors: Spoto Giuseppe
Published: July 2004

Chemistry plays an important role in the study of archaeological materials. Chemistry has developed methods to date archaeological material. It has also allowed us to infer trade routes by studying ancient artifacts and also shed light on the technology used to make them. The diet and customs of ancient peoples have also been discovered by applying chemical methods. Chemistry also intervenes in the understanding of the mechanisms that cause archaeological material to degrade.

The modern analytical methods available today have been used to study a wide range of archaeological inorganic, organic, and biological materials. A short overview of some of the most relevant achievements reached by applying chemical methods to archaeology is reported here.
Highly CO2‐Permeable and ‐Selective Membranes Derived from Crosslinked Poly(ethylene glycol) and Its Nanocomposites
Authors: Patel N. P. , Miller A. C. , Spontak R. J.
Published: July 2004

Crosslinked poly(ethylene glycol diacrylate) (PEGda) oligomers differing in molecular weight, and their nanocomposites prepared with up to 10 wt.‐% methacrylate‐functionalized fumed silica (FS) or an organically‐modified nanoclay, have been examined as amorphous CO2‐selective membranes. These novel materials have been characterized by dynamic rheology before and after crosslinking to ascertain the effect of incorporated FS on mechanical properties. The permeabilities of CO2, H2, N2, and O2 have been measured as functions of PEGda molecular weight, nanofiller content and temperature. In all cases, CO2 displays relatively high permeability, coupled with high CO2 selectivity, due to the specific interaction between quadrupolar CO2 and the ether linkages along the PEG backbone, and the accompanying enhancement in CO2 solubility. Variable‐temperature permeation exhibits Arrhenius behavior, and the activation energy for CO2 permeation is found to be i) markedly lower than that of any of the other gases examined, and ii) independent of both PEGda molecular weight and nanofiller content.
New Organic Metals Based on BDH‐TTP Radical Cation Salts with the Photochromic Nitroprusside Anion [FeNO(CN)5]2–
Authors: Shevyakova I. , Buravov L. , Tkacheva V. , Zorina L. , Khasanov S. , Simonov S. , Yamada J. , Canadell E. , Shibaeva R. , Yagubskii E.
Published: July 2004

Three new 2,5‐bis(1,3‐dithiolan‐2‐ylidene)‐1,3,4,6‐tetrathiapentalene (BDH‐TTP) radical cation salts with the photochromic nitroprusside anion have been synthesized: κ‐(BDH‐TTP)4[FeNO(CN)5]·NB (1), κ‐(BDH‐TTP)4[FeNO(CN)5] (2), and (BDH‐TTP)2[FeNO(CN)5] (3). The salts were characterized by single‐crystal X‐ray diffraction, electrical resistance measurements, and electronic band structure calculations. The crystals of 1 and 2 have a layered structure in which the BDH‐TTP layers of κ‐type alternate with anionic sheets. Solvent (nitrobenzene) molecules are also involved in the composition of the anion sheet of 1. The crystals of 1 have triclinic symmetry and two crystallographically independent BDH‐TTP radical cations in the unit cell, while there is only one independent radical cation in the monoclinic structure of 2. The salts 1 and 2 are stable quasi‐2D metals down to 4.2 K, while 3, with full charge transfer, is a semiconductor with low conductivity at room temperature. It is suggested that the κ‐type layers of BDH‐TTP are more robust than those of BEDT‐TTF and its derivatives and the consequences for the electronic structure are discussed.
Electron‐Enhanced Hole Injection in Blue Polyfluorene‐Based Polymer Light‐Emitting Diodes
Authors: van Woudenbergh T. , Wildeman J. , Blom P. W. M. , Bastiaansen J. J. A. M. , Langeveld‐Vos B. M. W.
Published: July 2004

It has recently been reported that, after electrical conditioning, an ohmic hole contact is formed in poly(9,9‐dioctylfluorene) (PFO)‐based polymer light‐emitting diodes (PLED), despite the large hole‐injection barrier obtained with a poly(styrene sulfonic acid)‐doped poly(3,4‐ethylenedioxythiophene) (PEDOT:PSS) anode. We demonstrate that the initial current at low voltages in a PEDOT:PSS/PFO‐based PLED is electron dominated. The voltage at which the hole injection is enhanced strongly depends on the electron‐transport properties of the device, which can be modified by the replacement of reactive end groups by monomers in the synthesis. Our measurements reveal that the switching voltage of the PLED is governed by the electron concentration at the PEDOT:PSS/PFO contact. The switching effect in PFO is only observed for a PEDOT:PSS hole contact and not for other anodes such as indium tin oxide or Ag.
Photoswitching of Ferroelectric Liquid Crystals Using Unsymmetrical Chiral Thioindigo Dopants: Photoinduced Inversion of the Sign of Spontaneous Polarization
Authors: Vlahakis J. Z. , Wand M. D. , Lemieux R. P.
Published: July 2004

A new unsymmetrical chiral thioindigo dopant 6‐[(R,R)‐2,3‐difluorooct‐1‐yloxy]‐5′‐nitro‐6′‐[(R)‐2‐octyloxy]thioindigo (4) designed to photoinvert the sign of spontaneous polarization (PS) in a ferroelectric chiral smectic C (SmC*) liquid crystal was prepared using a synthetic approach previously developed in our laboratory. In this new “ambidextrous” design, the (R)‐2‐octyloxy side‐chain is sterically coupled to the thioindigo core and induces a positive PS, whereas the (R,R)‐2,3‐difluorooctyloxy side‐chain is decoupled from the core and induces a larger negative PS. In the trans form, this dopant induces a negative polarization in the SmC host (+)‐4‐(4‐methylhexyloxy)phenyl 4‐decyloxybenzoate (PhB). Irradiation of a 1 mol‐% mixture of 4 in PhB at λ = 510 nm caused a sign inversion of PS, from –0.88 to +0.42 nC cm–2 at T – TC = –5 °C, which is consistent with an increase in the polarization power of the coupled 2‐octyloxy/thioindigo unit over that of the 2,3‐difluorooctyloxy unit, due to the increase in transverse dipole moment of the thioindigo core upon trans–cis photoisomerization. The PS sign inversion was confirmed by a surface‐stabilized ferroelectric liquid crystal photoswitching experiment. Spectroscopic measurements on films of the doped liquid crystal mixtures showed that trans–cis photoisomerization is gradually suppressed with increasing dopant mole fraction, possibly as a result of increased dopant aggregation.
Rapid detection of common Chinese glucose‐6‐phosphate dehydrogenase (G6PD) mutations by microarray‐based assay
Authors: Bang‐Ce Ye , Hongqiong Liu , Zhensong Lei
Published: July 2004

Glucose‐6‐phosphate dehydrogenase (G6PD) deficiency is the most common human enzymopathy, affecting more than 200 million people worldwide. To date more than 123 mutations in the G6PD gene have been discovered, among which 12 point mutations are found in the Chinese. Setting up a simple and accurate method for detecting these mutations is not only useful for diagnosing G6PD deficiency under some circumstances that it is difficult to measure the activity of the enzyme, but also for studying the frequency of the G6PD genotypes. The purpose of this study was to develop a simple, inexpensive and accurate method for detecting these common mutations. Microarray‐based assay was described in this study. Samples from 198 G6PD‐deficient persons were investigated. The DNA sequencing data supported the results obtained by microarray‐based assay. Thus, we concluded that the microarray‐based assay is a rapid, simple, inexpensive, and accurate method for detecting the most common G6PD gene mutations among the Chinese. This method involves the selective amplification of human G6PD gene with specific oligonucleotide primers, fragmentation and labeling of PCR products, followed by hybridization with allele‐specific oligonucleotide (ASO) probes on chip. Am. J. Hematol. 76:405–412, 2004. © 2004 Wiley‐Liss, Inc.
Use of dimensionless residence time to study variations in breakthrough behaviour in expanded beds formed from varied particle size distributions
Authors: Gardner P.J. , Willoughby N. , Hjorth R. , Lacki K. , Titchener‐Hooker N.J.
Published: July 2004

This work demonstrates an experimental method for studying breakthrough behaviour in expanded beds. The behaviour of beds made with differently sized particles were studied at varying flowrates. The use of a dimensionless residence time measurement allowed a more valid comparison of breakthrough characteristics in expanded bed operation by compensating for the changes in bed volume that occur during expansion. We demonstrate that bed breakthrough behaviour can be compared directly even when the beds contain different‐sized particles and hence have different expanded volumes. By utilising this concept we demonstrate that, in the case of the Alcohol Dehydrogenase (ADH) / STREAMLINE Phenyl system used here, there was little or no variation in ADH breakthrough behaviour between beds of differently sized particles operating at flowrates above 100 cm/h. This suggests that the higher specific surface area and hence binding capacity of smaller particles is negated in this case due to mass transfer limitations and the increase in system void volume even at normal operating flowrates of 200–300 cm/h. © 2004 Wiley Periodicals, Inc.
Purification of antibody and antibody‐fragment from E. coli homogenate using 6,9‐diamino‐2‐ethoxyacridine lactate as precipitation agent
Authors: Persson Josefine , Lester Philip
Published: July 2004

To obtain a more efficient purification process for antibody fragments from an Escherichia coli homogenate, the precipitant, Ethodin (6,9‐diamino‐2‐ethoxyacridine lactate) was introduced to the homogenate. By adding the precipitant a drastic reduction of host cell protein was obtained. The majority of the proteins were recovered in a precipitate with the cell debris, while the antibody or antibody‐fragment was recovered in the clarified supernatant. In addition, DNA was also efficiently precipitated when using Ethodin as a precipitation agent. The improved purity of the clarified extract obtained by using the precipitant allows for the use of smaller chromatography columns and may reduce the number of chromatographic steps required in the recovery process. The effect of Ethodin concentration, pH, temperature, and conductivity were investigated. The investigation was performed on two different antibody‐fragments, e.g., F(ab′)2 molecules and a full‐length antibody produced in E. coli. The two F(ab′)2 proteins were F(ab′)2A and F(ab′)2B, which have a similar molecular mass (100 kDa) but different isoelectric points (pIs), i.e., 8.9 and 7.5, respectively. The full‐length antibody, Ab (the full IgG form of F(ab′)2B) has a pI of 7.8 and molecular mass of 150 kDa. The investigation showed that the highest purification factors were obtained at neutral pH, low conductivity, and Ethodin concentrations of 0.6%. © 2004 Wiley Periodicals, Inc.
Rapid high‐performance liquid chromatographic measurement of buspirone in human plasma after overdose
Authors: Péhourcq F.
Published: July 2004

For toxicological purposes, a rapid reversed‐phase high‐performance liquid chromatographic method was developed for the determination of the anxiolytic drug, buspirone, in human plasma. A liquid–liquid procedure was used to extract this compound from plasma in the presence of an internal standard, quinupramine. The analysis was performed on a Spherisorb® S5 C8 analytical column with UV detection at 240 nm. No endogenous compounds were found to interfere. A linear response was observed over the concentration range 5–100 ng/mL. A good accuracy (bias ≤7.9%) was achieved for all quality controls, with intra‐day and inter‐day variation coefﬁcients equal or less than 7.6%. The limit of quantiﬁcation was 5 ng/mL. Stability of buspirone in plasma stored at different temperatures was checked. This rapid method (run time <12 min) was used to manage an acute poisoning involving buspirone. Copyright © 2004 John Wiley & Sons, Ltd.
Simultaneous determination of zidovudine and lamivudine from rat plasma, amniotic ﬂuid and tissues by HPLC
Authors: Alnouti Yazen , White Catherine A. , Bartlett Michael G.
Published: July 2004

A sensitive HPLC method has been developed and validated for the simultaneous quantiﬁcation of zidovudine (AZT) and lamivudine (3TC) in rat plasma, amniotic ﬂuid and placental and fetal tissues. Samples were processed by solid‐phase extraction using C2 cartridges. Chromatography was performed using a phenyl column (5 µm, 150 × 2 mm i.d.) under a ﬂow rate of 0.2 mL/min. The mobile phase consisted of 8% acetonitrile in 5 mm 1‐heptane sulfonic acid dissolved in 30 mm ammonium formate buffer (pH 3.3). The method was validated in the range 0.25–50 µg/mL for both 3TC and AZT in the four biological matrices. Finally, the method was applied to a study involving fetal transport of co‐administration of these compounds in a pregnant rat. Copyright © 2004 John Wiley & Sons, Ltd.
Hair analysis of nicotine and cotinine for evaluating tobacco smoke exposure by liquid chromatography–mass spectrometry
Authors: Chetiyanukornkul Thaneeya , Toriba Akira , Kizu Ryoichi , Kimura Kazuko , Hayakawa Kazuichi
Published: July 2004

A simple liquid chromatography–electrospray ionization mass spectrometry (LC‐ESI‐MS) method for the determination of nicotine and cotinine in human hair was established. In the procedure, a hair sample (10 mg) was washed with dichloromethane and digested in 2.5 m sodium hydroxide. The digest was extracted with dichloromethane and then 25 mm hydrochloric acid in methanol was added to the extract, to prevent loss of analytes. The solution was evaporated and redissolved in the mobile phase, methanol/10 mm ammonium acetate (30/70, v/v). A 20 µL aliquot of redissolved solution was subjected to analysis. Nicotine and cotinine in human hair were quantiﬁed by using deuterated analytes as internal standards. The quantiﬁcation limits were 8 µg/L for nicotine and 0.9 µg/L for cotinine. The proposed method was applied to measure the concentrations of nicotine and cotinine in hair of smokers and non‐smokers to evaluate their self‐reported smoking and exposure to environmental tobacco smoke. In both cases, the method provided good selectivity, accuracy and precision. Copyright © 2004 John Wiley & Sons, Ltd.
HPLC identiﬁcation of oversulphated chondroitin as the major glycosaminoglycan of human tonsils
Authors: Triantaphyllidou I. E. , Mastronikolis N. S. , Papadas Th. A. , Vynios D. H.
Published: July 2004

The glycosaminoglycans of human nasopharyngeal and palatine tonsils, obtained after surgical dissection due to tonsillitis, were isolated and characterized by means of enzyme susceptibility and HPLC. Chondroitin/dermatan sulphate were the major glycosaminoglycans identiﬁed. A large proportion of this glycosaminoglycan was made up of oversulphated structures, namely ΔDi‐di(4,6)S, which were found mainly in invertebrate tissues and in mast cells. Copyright © 2004 John Wiley & Sons, Ltd.
An automated analyzer for vancomycin in plasma samples by column‐switching high‐performance liquid chromatography with UV detection
Authors: Saito Mitsue , Santa Tomofumi , Tsunoda Makoto , Hamamoto Hiroshi , Usui Noriko
Published: July 2004

An automated analyzer for vancomycin in rat plasma by column‐switching high‐performance liquid chromatography (HPLC) with UV detection was developed. The method includes in‐line extraction of vancomycin by ion‐exchange cartridge column and a separation on a reversed‐phase column with UV detection at 215 nm. Plasma samples were diluted by mobile phase solution and directly injected to HPLC. Vancomycin was quantitatively recovered from rat plasma samples. The separation was completed within 15 min. The calibration curve was linear over the range from 0.5 to 100 µg/mL with the detection and quantiﬁcation limits of 0.5 µg/mL (2.5 ng on column; signal‐to‐noise ratio = 3). The values of precision in intra‐ and inter‐day assays (n = 3) were less than 1.92 and 3.69%, respectively. This method does not require time‐consuming pre‐treatment and is suitable for the routine assay of plasma samples. Copyright © 2004 John Wiley & Sons, Ltd.
Challenges in implementing evidence‐based treatment practices for co‐occurring disorders in the criminal justice system
Authors: Chandler Redonna K. , Peters Roger H. , Field Gary , Juliano‐Bult Denise
Published: July 2004

The presence of adults with mental health and substance abuse disorders within the criminal justice system has become increasingly evident over the past decade. Interventions and treatment services have been designed and research conducted in an effort to establish evidence‐based practices that effectively address the complex needs of this population. However, adopting and implementing these evidence‐based interventions and practices within the real‐world setting of criminal justice environments is challenging. This article reviews the research literature related to evidence‐based treatment practices for offenders with co‐occurring mental health and substance abuse disorders and explores the inherent challenges of fitting these interventions and services within criminal justice settings. Copyright © 2004 John Wiley & Sons, Ltd.
Modified TC for MICA offenders: crime outcomes
Authors: Sacks Stanley , Sacks JoAnn Y. , McKendrick Karen , Banks Steven , Stommel Joe
Published: July 2004

The study randomly assigned male inmates with co‐occurring serious mental illness and chemical abuse (MICA) disorders to either modified therapeutic community (MTC) or mental health (MH) treatment programs. On their release from prison, MICA inmates who completed the prison MTC program could enter the MTC aftercare program. The results, obtained from an intent‐to‐treat analysis of all study entries, showed that inmates randomized into the MTC group had significantly lower rates of reincarceration compared with those in the MH group. The results also show that differences between the MTC + aftercare and comparison group across a variety of crime outcomes (i.e. any criminal activity, and alcohol or drug related criminal activity) are consistent and significant, and persist after an examination of various threats to validity (e.g. initial motivation, duration of treatment, exposure to risk). This study provides some support for the effectiveness of the prison TC only condition. The findings are encouraging and consonant with other studies of integrated prison and aftercare TC programs for substance abusing non‐MICA offenders, although qualified by the possibility that selection bias (i.e. differences in motivation on entry into aftercare) may be operating. Nevertheless, given the available evidence and the need for effective programming for MICA offenders, program and policy makers should strongly consider developing integrated prison and aftercare modified TC programs for MICA offenders. Copyright © 2004 John Wiley & Sons, Ltd.
One year return to custody rates among co‐disordered offenders
Authors: Messina Nena , Burdon William , Hagopian Garo , Prendergast Michael
Published: July 2004

The extent to which therapeutic community (TC) methods meet the treatment needs of offenders with substance abuse disorders and co‐occurring psychiatric disorders in prison is largely unknown. Very little research has been conducted with this population. The purposes of this study were to generate profiles of co‐disordered drug offenders entering TC treatment in prison and to assess their post‐release reincarceration rates, compared with drug offenders without psychiatric disorders. Extensive intake interview data for over 8,500 men and women who received treatment in one of 16 prison‐based TCs in California were analyzed to produce profiles of co‐disordered participants. Intake data come from a 5 year process and outcome evaluation of the California Department of Corrections' (CDC's) treatment initiative. Post‐release reincarceration rates come from the CDC's Offender Based Information System. Compared with non‐psychiatric disordered drug offenders, co‐disordered offenders had substantially more severe substance abuse and criminal histories, in addition to their psychiatric impairment, at treatment entry. Logistic regression results indicated that, compared with drug offenders without psychiatric illness, co‐disordered offenders were significantly more likely to be reincarcerated during the first year of their parole. These results suggest that prison treatment programs may need to use more comprehensive diagnostic assessments at intake to assess the diverse mental health needs of drug offenders with co‐occurring psychiatric disorders and to develop treatment approaches suitable for this population. Copyright © 2004 John Wiley & Sons, Ltd.