An improved method for isolation of unconjugated bilirubin from rat and dog bile

Radiolabeled unconjugated bilirubin (UCB) is currently prepared by biosynthetic labeling of bilirubin in fistula bile from precursor-labeled delta-aminolevulinic acid (ALA) in rats or dogs. With existing methods, yields of labeled UCB from the bile are generally less than 50%. We here report modifications of the original method of Ostrow et al (Ostrow JD, Hammaker L, Schmid R. The preparation of crystalline bilirubin-C(14). J Clin Invest 1961;40:1442-52) that result in improvement of yields to 72% from both dog and rat bile. The modifications include the initial deproteination of bile with a reverse-phase C18 cartridge, removal of ethanol before alkaline hydro-lysis to avoid esterification of UCB, and adjustments for the high proportion of non-glucuronide UCB conjugates in dog bile not precipitated as lead salts. These improvements should save significantly on both costs and animal usage.

Evolution of techniques for ultrasound-guided palladium 103 brachytherapy in 950 patients with prostate cancer

PURPOSE

Brachytherapy is an effective, low-morbidity, cost-effective treatment for adenocarcinoma of the prostate. Although both iodine 125 and palladium 103 have been used extensively over the last 14 years, 103Pd (Theraseed) provides a more rapid initial dose and therefore better control of higher Gleason grade tumors. We assessed a highly refined methodology for 103Pd brachytherapy in patients with prostate cancer and compared outcomes before and after making adjustments in technique.

MATERIALS AND METHODS

Standard brachytherapy techniques were modified to include combination of preplanning with real-time adjustment, placing all needles at once to minimize prostate movement, using monitored anesthesia control sedation during preoperative volume study and cystoscopy, and several other small but important changes. Charts were reviewed from 950 patients treated with 103Pd implants from 1991 through 1999. Prostate-specific antigen (PSA) and biopsy data before and after 1993 were compared for 733 patients whose data qualified for analysis.

RESULTS

At 1 and 5 years after treatment, 85-88% of patients had stable PSA <1.5 ng/mL. Biopsies were negative in 90-94% at 2 years.

CONCLUSION

The modification in techniques provides positive results that remain stable over time.

Minimally invasive treatment for localized adenocarcinoma of the prostate: review of 1048 patients treated with ultrasound-guided palladium-103 brachytherapy

PURPOSE

To assess the effectiveness of palladium-103 brachytherapy in stage T1 and T2 adenocarcinoma of the prostate.

PATIENTS AND METHODS

The charts of 1048 patients treated between 1991 and 1999 with transperineal realtime ultrasound-guided (103)Pd (Theraseed) implants were reviewed to assess the effects on serum prostate specific antigen (PSA) values and tissue (biopsy). Of the 1048 patients, 780 had sufficient data for this report. Preoperative total androgen blockade (leuprolide and flutamide) was used selectively in patients whose prostate size was >50 cc and those whose tumors had a Gleason score of >7.

RESULTS

At 1 year, 86% of the evaluable 766 patients had stable PSA concentration <1.5 ng/mL; at 5 years, 86% of the 166 patients with data available had stable PSA values <1.5 ng/mL. Biopsies were negative in 92% of the patients studied at 2 years. Patients with pretreatment PSA values <10 ng/mL had the best outcomes, and those treated with (103)Pd plus hormone ablation achieved PSA reduction more rapidly than those treated with radioisotope monotherapy. There was one disease-related death; the principal morbidity was short-term bladder and bowel irritation without permanent sequelae. Impotence occurred in approximately 15% of patients, and incontinence occurred in 5% of those who had undergone prior transurethral resection of the prostate.

CONCLUSION

The technique used in this study proved effective in reducing PSA concentrations to <1.5 ng/mL and in producing negative biopsies 1 and 2 years postoperatively. These results are comparable to those of external-beam radiation therapy and radical prostatectomy while demonstrating a significant reduction in morbidity.

Identification of natural ligands for SH2 domains from a phage display cDNA library

The cytoplasmic domain of the Fc gamma receptor IIB (FcgammaRIIB) can be successfully displayed on the surface of filamentous phage, and after phosphorylation in vitro, can interact specifically with the SH2 domains of SHP-2, a cytoplasmic tyrosine phosphatase. When full-length FcgammaRIIB is expressed on phage, however, this interaction is greatly compromised, illustrating that characteristics of the full-length sequence are not well tolerated by the phage display system. Many associations in cell physiology are driven by similar interactions involving small modular binding domains or ligands, and so a fragmented cDNA library will facilitate display of such domains free of sequences which compromise their expression. A fragmented leukocyte cDNA display library of 10(8) clones was constructed. This library was phosphorylated in vitro with fyn kinase and was selected against the tandem SH2 domains of SHP-2 in the search for additional ligands. A depletion strategy to remove non-specific clones was employed, using SHP-2 Sepharose, prior to in vitro phosphorylation and selection. This permitted the emergence of clones encoding the cytoplasmic domain of PECAM-1, another natural ligand for SHP-2. The importance of dual phosphorylation of tyrosine residues at positions 663 and 686 was confirmed in competition ELISA experiments using phosphorylated phage and synthetic peptides. Thus, phage display of fragmented cDNA libraries permits the identification and characterisation of phosphorylated ligands of modular binding domains based on their functional interaction.

Patterns of protein synthesis and tolerance of anoxia in root tips of maize seedlings acclimated to a low-oxygen environment, and identification of proteins by mass spectrometry

Tolerance of anoxia in maize root tips is greatly improved when seedlings are pretreated with 2 to 4 h of hypoxia. We describe the patterns of protein synthesis during hypoxic acclimation and anoxia. We quantified the incorporation of [(35)S]methionine into total protein and 262 individual proteins under different oxygen tensions. Proteins synthesized most rapidly under normoxic conditions continued to account for most of the proteins synthesized during hypoxic acclimation, while the production of a very few proteins was selectively enhanced. When acclimated root tips were placed under anoxia, protein synthesis was depressed and no "new" proteins were detected. We present evidence that protein synthesis during acclimation, but not during subsequent anoxia, is crucial for acclimation. The complex and quantitative changes in protein synthesis during acclimation necessitate identification of large numbers of individual proteins. We show that mass spectrometry can be effectively used to identify plant proteins arrayed by two-dimensional gel electrophoresis. Of the 48 protein spots analyzed, 46 were identified by matching to the protein database. We describe the expression of proteins involved in a wide range of cellular functions, including previously reported anaerobic proteins, and discuss their possible roles in adaptation of plants to low-oxygen stress.

Health-related hardiness and the effect of a psycho-educational group on clients' symptoms

In the health literature, an individual's ability to resist illness when under stress has been referred to as 'hardiness'. Resources, which may be used to sustain a sense of well being, can be categorized by two broad domains, 'control' and 'commitment and challenge'. In this research, a quasi-experimental nonequivalent control group design was used to determine the impact of a specific clinical nursing intervention (the Wellness Program) in terms of its usefulness in fostering the development of health-related hardiness. Findings demonstrated a significant reduction in symptoms related to obsessive compulsiveness, hostility, psychoticism and average level of distress after subjects completed a relatively short psycho-educational health promotion group. Subjectively, the treatment group subjects also described positive changes in thoughts, feelings and behaviours. This research has implications for clinical interventions using small groups to promote health.

Identification of a nucleic acid binding domain in eukaryotic initiation factor eIFiso4G from wheat

Higher plants have two complexes that bind the m7G-cap structure of mRNA and mediate interactions between mRNA and ribosomal subunits, designated eIF4F and eIFiso4F. Both complexes contain a small subunit that binds the 5'-cap structure of mRNA, and a large subunit, eIF4G or eIFiso4G, that binds other translation factors and RNA. Sequence-specific proteases were used to cleave native cap-binding complexes into structural domains, which were purified by affinity chromatography. We show here that eIFiso4G contains a central protease-resistant domain that binds specifically to nucleic acids. This domain spans Gln170 to Glu443 and includes four of the six homology blocks shared by eIFiso4G and eIF4G. A slightly shorter overlapping sequence, from Gly202 to Lys445, had no nucleic acid binding activity, indicating that the N-terminal end of the nucleic acid binding site lies within Gln170 to Arg201. The binding of the central domain and native eIFiso4F to RNA homopolymers and double- and single-stranded DNAs was studied. Both molecules had highest affinity for poly(G) and recognized single- and double-stranded sequences.

Team leadership: network differences in women's and men's instrumental and expressive relations

Recent studies have emphasised differences in leadership styles between women and men. Women have an "interactive" leadership style while men are more "directive" and "authoritative." Social network analysis is used to examine differences in eight mental health case management teams, half formally supervised by women and half by men. The techniques used are graphical displays and measures of centrality. Results show male leaders as the most central team member for both instrumental and expressive relations. Female leaders, however, do not adhere to a single leadership style. Team centralisation also differs with gender composition of teams influencing leadership differences.

Rates of tuberculosis infection in healthcare workers providing services to HIV-infected populations. Terry Beirn Community Programs for Clinical Research on AIDS

OBJECTIVE

To assess the prevalence of tuberculosis (TB) or a positive skin test in healthcare workers (HCWs) providing services to human immunodeficiency virus (HIV)-infected individuals and to determine prospectively the incidence of new infections in this population.

DESIGN

This prospective cohort study enrolled 1,014 HCWs working with HIV-infected populations from 10 metropolitan areas. Purified protein derivative (PPD) tuberculin skin tests were placed at baseline and every 6 months afterwards on those without a history of TB or a positive PPD. Demographic, occupational, and TB exposure data also were collected.

SETTING

Outpatient clinics, hospitals, private practice offices, and drug treatment programs providing HIV-related healthcare and research programs.

PARTICIPANTS

A voluntary sample of staff and volunteers from 16 Community Programs for Clinical Research on AIDS units.

RESULTS

Factors related to prior TB or a positive skin test at baseline included being foreign-born, increased length of time in health care, living in New York City, or previous bacille Calmette-Guerin vaccination. The rate of PPD conversion was 1.8 per 100 person years of follow-up. No independent relation was found between the amount or type of contact with HIV-infected populations and the risk of TB infection.

CONCLUSION

These data provide some reassurance that caring for HIV-infected patients is not related to an increased rate of TB infection among HCWs in these settings.

Medical affective computing: medical informatics meets affective computing

"The need to cope with a changing and partly unpredictable world makes it very likely that any intelligent system with multiple motives and limited powers will have emotions." [1] From advisory systems that understand emotional attitudes toward medical outcomes, to wearable computers that compensate for communication disability, to computer simulations of emotions and their disorders, the research agendas of medical informatics and affective computing--how and why to create computers that detect, convey, and even have emotions--increasingly overlap. Some psychiatric and neurological researchers state their theories in terms of actual or hypothetical computer programs. Adaptive intelligent systems will increasingly rely on emotions to compensate for their own conflicting goals and limited resources--emotional reactions about which psychiatrists and neurologists have special insights. DEP2 (Depression Emulation Program 2) is a computer simulation of adaptive depression--learning from explainable patterns of failure in autobiographical memory--that simulates many depressive behaviors. In the terminology of fault-tolerant computing, adaptive depression involves fault detection (triggered by failure), fault location (strategic retreat and failure diagnosis), and fault recovery (return to on-line operation). DEP2 relies on subsystems whose structures and behaviors are based on popular hypotheses about left and right brain hemispheric function during depression and emotion. DEP2 and its predecessors, DEP and DEPlanner, are relevant to psychiatric and neurological informatics, and to the design of adaptive autonomous robots and software agents.

Urinary recovery of lactulose compared to D-xylose absorption kinetics in HIV patients with diarrhea and weight loss

Using a kinetic model of D-xylose absorption, we have previously shown that there is severely impaired absorption of D-xylose in HIV patients with diarrhea and weight loss. The absorptive defect is characterized by an increased rate constant for nonabsorptive loss of D-xylose, Ko, and a decreased absorptive rate constant, Ka, and is unrelated to histology or the presence of pathogens. It is not known if there is also abnormal paracellular transport in these patients. We have extended our observations in these patients by including a measurement of paracellular transport, lactulose absorption. Nine HIV patients with chronic diarrhea, weight loss, and no detectable intestinal pathogens, two healthy volunteers, and three non-HIV patients with chronic diarrhea (two functional and one with scleroderma) were enrolled. Of the nine HIV patients, six had diminished bioavailability of D-xylose, F (range: 19-52%, normal >70%), and elevated rate constant for nonabsorptive loss, Ko (range: 0.54-1.35/hr, normal <0.353/min). Four of the six also had decreased Ka (range: 0.09-0.36/hr, normal >0.634/min). Only one of these six had increased lactulose recovery (3.51%, normal <0.5%). Two of three patients with normal kinetic parameters of D-xylose absorption had increased lactulose urinary recovery (1.92%, 2.61%). In conclusion, lactulose absorption is increased in some patients with HIV-related diarrhea who have normal D-xylose absorption, suggesting a paracellular mechanism for diarrhea in some patients with AIDS enteropathy.

Naratriptan is effective and well tolerated in the acute treatment of migraine. Results of a double-blind, placebo-controlled, parallel-group study. Naratriptan S2WA3001 Study Group

OBJECTIVE

To evaluate the efficacy and tolerability of naratriptan, a novel 5-HT1 agonist, in the acute treatment of migraine.

DESIGN/METHODS

Six hundred thirteen migraineurs, diagnosed according to International Headache Society criteria, treated a single migraine attack with naratriptan tablets (2.5 mg, 1 mg, 0.25 mg, or 0.1 mg) or placebo in a randomized, double-blind, placebo-controlled, parallel-group study conducted at 54 United States centers. At dosing and at predetermined intervals beginning 30 minutes postdose, patients recorded migraine pain severity, clinical disability, and presence of associated migraine symptoms. Safety measures included adverse events, physical examinations, vital signs, ECGs, and clinical laboratory tests.

RESULTS

Headache relief (moderate or severe pain at dosing reduced to mild or no pain) 4 hours postdose was reported in 60% of patients receiving naratriptan 2.5 mg compared with 50%, 35%, 32%, and 34% of patients receiving naratriptan 1 mg, 0.25 mg, 0.1 mg, and placebo, respectively (P < 0.05 naratriptan 2.5 mg and 1 mg versus placebo, 1 mg versus 0.1 mg, and 2.5 mg versus 0.1 mg and 0.25 mg). Clinical disability 4 hours postdose was reported as mild or none for 70% of patients receiving naratriptan 2.5 mg compared with 63%, 47%, 48%, and 48% of patients receiving naratriptan 1 mg, 0.25 mg, 0.1 mg, or placebo, respectively (P < 0.05 naratriptan 2.5 mg and 1 mg versus placebo, 1 mg versus 0.1 mg, and 2.5 mg versus 0.1 mg and 0.25 mg). Four-hour efficacy for absence of nausea, photophobia, and phonophobia was similar to efficacy for headache relief at each dose. The adverse event profile of each dose of naratriptan was similar to that of placebo. No clinically relevant change in any safety measure was reported.

CONCLUSIONS

Naratriptan is effective and well tolerated for the acute treatment of migraine. The 2.5-mg dose appears to offer the optimum ratio of efficacy to tolerability.

NHS charges. Light on the charge brigade

Patients charges form a very small part of NHS income. Governments have often used charges to emphasise their commitment to austerity. Knowledge of the effect of charges on public health, equity and eliminating waste is limited. Both Conservative and Labour health ministers have made attempts to abolish charges.

The safety of ranitidine in over a decade of use

BACKGROUND

Ranitidine hydrochloride (Zantac) is one of the most extensively studied and widely used drugs of all time. This has provided an excellent opportunity to define its safety profile.

METHODS

Data from 189 controlled clinical trials in which more than 26,000 patients received daily doses of ranitidine for 4 weeks or more were reviewed. More than 80% of patients were treated with up to 300 mg ranitidine daily; the remaining patients received doses of up to 1200 mg daily. Eighty-seven trials were placebo controlled. Analyses of post-marketing surveillance and a database of all spontaneously reported adverse events were also evaluated.

RESULTS

Overall in the clinical trial programme adverse events were reported by 20% of those receiving ranitidine compared with 27% of those receiving placebo. The pattern of events was similar in all treatment groups with no evidence of dose-related toxicity in regimens encompassing an eightfold range of therapeutic doses. Similarly in a programme of studies designed to evaluate a dose of ranitidine of 75 mg for non-prescription (over-the-counter) use in the treatment of heartburn, ranitidine was not associated with an adverse event profile distinct from that of placebo. Analysis of spontaneously reported adverse event data allowed identification of rare idiosyncratic events.

CONCLUSIONS

Review of data from a large population of controlled clinical trials with analyses of postmarketing surveillance studies and spontaneously reported adverse events confirmed the excellent safety profile of ranitidine.