The mitogen-activated protein kinase/extracellular signal-regulated kinase kinase inhibitor PD184352 (CI-1040) selectively induces apoptosis in malignant schwannoma cell lines

Type 1 neurofibromatosis (NF1) is a common autosomal dominant disorder that results in neuroectodermal tumors. The NF1 tumor-suppressor gene encodes neurofibromin, which includes a GTPase-activating domain for Ras inactivation. Affinity purification showed N-Ras to be the predominant activated isoform of Ras in two independent neurofibrosarcoma cell lines from NF1 patients (lines ST88-14 and NF90-8). These NF1 cells also demonstrated increased constitutive activity of the extracellular signal-regulated kinases 1 and 2 (ERK1,2) mitogen-activated protein (MAP) kinases compared with a sporadic malignant schwannoma cell line that maintains neurofibromin expression (STS-26T). Thus, MAP kinase kinase (MEK) inhibitors may be a rational approach to NF1 therapy. The MEK inhibitors PD98059 [2'-amino-3'-methoxyflavone], PD184352 (also called CI-1040) [2-(2-chloro-4-iodo-phenylamino)-N-cyclopropylmethoxy-3,4-difluoro-benzamide], and U0126 [1,4-diamino-2,3-dicyano-1,4-bis(2-aminophenylthio)butadiene] all produced concentration-dependent suppression of the proliferation of the three cell lines. Individual MEK inhibitors had similar effects in all three cell lines. However, only the antiproliferative effects of PD184352 correlated closely with the elimination of ERK1,2 MAP kinase activities. PD98059 was primarily cytostatic, whereas U0126 and PD184352 were cytotoxic. Only PD184352 induced apoptosis in all three lines, as indicated by morphology, activation of DEVDase, procaspase-3 cleavage, and the appearance of populations having sub-G(0)/G(1) DNA contents. The differential effects of the MEK inhibitors on cell survival were not dependent on p53 status or effects on the ERK5 pathway. PD184352 was also proapoptotic to primary rat Schwann cells. Hence, although PD184352 effectively killed neurofibrosarcoma cells, its effects on normal Schwann cells may limit its usefulness in the clinic.     

Common data elements for posttraumatic stress disorder research

Kaloupek DG, Chard KM, Freed MC, Peterson AL, Riggs DS, Stein MB, Tuma F. Common data elements for posttraumatic stress disorder research.An expert work group with 7 members was formed under the cosponsorship of 5 U.S. federal agencies to identify common data elements for research related to posttraumatic stress disorder (PTSD). The work group reviewed both previous and contemporary measurement standardization efforts for PTSD research and engaged in a series of electronic and live discussions to address a set of predefined aims. Eight construct domains relevant to PTSD were identified: (1) traditional demographics, (2) exposure to stressors and trauma, (3) potential stress moderators, (4) trauma assessment, (5) PTSD screening, (6) PTSD symptoms and diagnosis, (7) PTSD-related functioning and disability, and (8) mental health history. Measures assigned to the core data elements category have relatively low time-and-effort costs in order to make them potentially applicable across a wide range of studies for which PTSD is a relevant condition. Measures assigned to the supplemental data elements category have greater costs but generally demonstrate stronger psychometric performance and provide more extensive information. Accordingly, measures designated as supplemental are recommended instead of or in addition to corresponding core measures whenever resources and study design allow. The work group offered 4 caveats that highlight potential limitations and emphasize the voluntary nature of standardization for PTSD-related measurement.     

Bioavailability and Metabolism of Potassium Phosphanilate in Laboratory Animals and Humans

Phosphanilic acid is an antibacterial agent with a mode of action and antibacterial spectrum similar to those of sulfamethoxazole, with the exception that it has potent antipseudomonal activity. Bioavailability studies in rats (50, 300, and 600 mg/kg, oral and subcutaneous), dogs (50, 150, and 450 mg/kg, oral and intravenous infusion), and humans (400 and 800 mg, oral) showed that the extent of oral absorption of potassium phosphanilate was low. The bioavailability, calculated by comparing the oral values for area under the plasma concentration curve with those for the respective parenteral doses, was 10% for rats and 45 (50 and 150 mg/kg) and 19% (450 mg/kg) for dogs. The 24-h urinary recovery also confirmed the low oral bioavailability, i.e., rat, 13 (oral) and 75% (subcutaneous); dog, 15 to 29 (oral) and 87% (intravenous) of the dose. Plasma levels and urinary recovery (4%, oral) were low and variable in humans. The poor absorption of oral doses may be due to drug precipitation in the stomach, low permeability of the soluble species due to extensive in situ ionization (pK_a, 1.8 to 2) in the intestine, or first-pass metabolism to N-acetylphosphanilic acid. The plasma t_½ values after parenteral administration were 0.3 h in rats and 1.3 h in dogs. Although the lack of adequate blood levels of phosphanilic acid after oral administration in humans precludes the use of this compound for treatment of systemic infections, the sustained urinary concentration at levels severalfold higher than the minimal inhibitory concentration (1 μg/ml) for at least 10 h postdose was indicative of the therapeutic usefulness in urinary tract infections.     

Evaluation of fetal intracranial anatomy by static and real-time ultrasound

Improvements in ultrasound technology have now made possible detailed visualization of fetal intracranial anatomy. Structures such as the midbrain, thalami, and lateral ventricles can be routinely imaged. Measurements of the ratio between lateral ventricular width and cerebral hemispheric width demonstrate a steady decrease from a mean of 56% at 15 wk gestation to 28% at term reflecting the relatively more rapid growth of the cerebral hemispheres as compared with the cerebral ventricles. Application of this new ultrasound data greatly facilitates accurate and consistent biparietal diameter estimations and early diagnosis of fetal hydrocephalus and other fetal cranial anomalies. This article describes the axial fetal cranial anatomy as demonstrated sonically and includes a table for normal fetal ventricular size at various gestational ages, based on evaluation of 196 normal fetuses. Some of the more common fetal cranial anomalies amenable to ultrasound diagnosis in utero are discussed.     

Inhibition of Escherichia coli K-12 by β-Lactam Antibiotics With Poor Antibacterial Activity: Interaction of Permeability And Intrinsic Activity Against Penicillin-Binding Proteins

The effect of methicillin, cloxacillin, 1078/1/1, penicillin G, and cephaloridine upon the penicillin-binding proteins of a permeability mutant of Escherichia coli K-12 and its isogenic wild type have been investigated. Comparison of the 50% inhibition values for the antibiotics against the penicillin-binding proteins of the two strains with the minimal inhibitory concentrations for the same compounds indicates that methicillin, cloxacillin, 1078/1/1, and to a lesser extent penicillin G, owe their poor antibacterial activity to exclusion from the bacterial cell, whereas cephaloridine is not excluded and is equally active against both the mutant and its wild type. The results further suggest that the lesion in the permeability mutant E. coli DC2 allows free access of all the compounds tested to the inner membrane target proteins.     

Effectiveness of budesonide administered via dry-powder inhaler versus triamcinolone acetonide administered via pressurized metered-dose inhaler for adults with persistent asthma in managed care settings

BACKGROUND: Clinical studies have demonstrated the efficacy and relative safety of inhaled corticosteroids in the treatment of asthma. However, effectiveness and cost-effectiveness comparisons of available inhaled corticosteroids in real-life clinical settings are lacking. OBJECTIVE: This study compared the effectiveness and safety of budesonide administered via dry-powder inhaler versus that of triamcinolone acetonide administered via pressurized metered-dose inhaler in the treatment of adult patients with persistent asthma treated in a managed care setting. METHODS: This was a randomized, open-labe, 52-week study of adult patients (aged >or= 18 years) with persistent asthma enrolled in 25 US health plans. The primary study outcome was mean change from baseline to the end of treatment in symptom-free days. Secondary variables were changes from baseline in number of episode-free days, episode-free days at 52 weeks, forced expiratory volume in 1 second (FEV(1)), forced vital capacity, asthma symptom scores, breakthrough bronchdilator use, patient discontinuations, and health-related quality of life. Patients were issued diaries in which to record use of study medication and concomitant asthma medication use, as well as daytime and nighttime asthma symptom severity. Patients were assessed at weeks 4, 13, 26, 39, and 52. Safety was assessed based on adverse events and changes in laboratory tests, vital signs, and physical examinations. RESULTS: A total of 945 patients (344 men, 601 women; mean [SD] age, 46.8 [14] years) were enrolled; 631 received budesonide and 314 received triacinolane acetonide. Improvements in all effectiveness variables were observed with both treatments. The mean increase from baseline in the number of symptom-free days per month assessed at month 12 was 7.74 (95% CI, 6.81-8.66) for patients receiving budesonide and 3.78 (95% CI, 2.47-5.09) for patients receiving triamcinoline acetonide ( P<0.001). The estimated annual mean (SD) number symptom-free days for patients receiving budesonide was 141.1 (125.0) over the treatment phase, compared with 99.3 (112.1) for those receiving triamcinolone acetonide (P<0.001). Patients receiving budesonide demonstrated significant improvements (compared with those receiving triamcinolone acetonide) in overall quality of life, daytime and nighttime asthma symptom severity, breakthrough bronchodilator use, and FEV(1) (all P<0.001). Safety measures were similar between groups. CONCLUSION: In these managed care settings, budesonide inhalation powder administered via dry-powder inhaler was significantly more effective than triamcinolone acetonide administered via pressurized metered-dose inhaler in the treatment of adults with persistent asthma.     

Catecholamine-induced T-wave lability in congenital long QT syndrome: a novel phenomenon associated with syncope and cardiac arrest

OBJECTIVE: To determine the effects of phenylephrine and dobutamine on repolarization lability in patients with genotyped long QT syndrome (LQTS). PATIENTS AND METHODS: Between December 1998 and August 2000, 23 patients with genotyped LQTS (13 LQT1, 7 LQT2, and 3 LQT3) and 16 controls underwent electrocardiographic stress testing at the Mayo Clinic in Rochester, Minn. Aperiodic repolarization lability was quantified from digitized electrocardiograms recorded during catecholamine stress testing with phenylephrine and dobutamine. T-wave lability was quantified as a root-mean-square of the differences between corresponding signal values of subsequent beats. The magnitude of aperiodic T-wave lability was quantified by using a newly derived T-wave lability index (TWLI). RESULTS: The TWLI was significantly greater in patients with LQTS than in controls (0.0945 +/- 0.0517 vs 0.0445 +/- 0.0123; P < .003). Marked T-wave lability (TWLI > or = 0.095) was detected in all 3 LQTS genotypes (10/23) but in no controls (P < .003). There was no correlation between the TWLI and the baseline corrected QT interval. All high-risk patients having either a history of out-of-hospital cardiac arrest or syncope had a TWLI of 0.095 or greater. CONCLUSIONS: Beat-to-beat nonalternating T-wave lability occurs in LQT1, LQT2, and LQT3 patients during catecholamine provocation and is associated with a history of prior cardiac events. The quantification of this novel phenomenon may assist in identifying LQTS patients with increased risk of sudden cardiac death.     

Interprofessional care co-ordinators: the benefits and tensions associated with a new role in UK acute health care

While more flexible models of service delivery are being introduced in UK health and social care, little is known about the impact of new roles, particularly support worker roles, on the work of existing practitioners. This action research study aimed to explore the impact of one such new role, that of interprofessional care co-ordinators (IPCCs). The general (internal) medical service of a UK hospital uses IPCCs to provide support to the interprofessional team and, in doing so, promote efficiency of acute bed use. Using a range of methods, mainly qualitative, this action research study sought to explore the characteristics and impact of the role on interprofessional team working. While the role's flexibility, autonomy and informality contributed to success in meeting its intended objectives, these characteristics also caused some tensions with interprofessional colleagues. These benefits and tensions mirror wider issues associated with the current modernisation agenda in UK health care.     

Measuring clinical pain in chronic widespread pain: selected methodological issues

Assessing clinical pain is an important task in clinical practice and research. A large empirical literature has documented that patients' pain reports can be systematically biased by a number of methodological factors. This chapter reviews a selection of methodological issues that can affect pain ratings, including: the impact of recall bias, the use of paper and electronic diaries to assess pain experiences, ecological momentary assessment methods as a way of capturing real-time pain data in the real world, and pain scaling and data analysis considerations. Data from a recent study that implemented an electronic diary for capturing real-time pain data are presented and reviewed in the context of the methodological factors reviewed above. It is concluded that methodological factors can greatly affect our understanding of patients' pain experiences.