Reasons for adherence with antihypertensive medication

BACKGROUND

Hypertension is often insufficiently controlled in clinical practice, a prominent reason for this being poor patient adherence with therapy. Little is known about the underlying reasons for poor adherence. We set out to investigate hypertensive patients' self-reported reasons for adhering to or ignoring medical advice regarding antihypertensive medication.

METHODS

Qualitative analysis of semi-structured interviews with 33 hypertensive patients in a general-practice centre and a specialist hypertension unit in Southern Sweden. Blood-pressure measurements and laboratory measurements of antihypertensive medication were performed.

RESULTS

Nineteen out of 33 patients were classified as adherent. Adherence was a function of faith in the physician, fear of complications of hypertension, and a desire to control blood pressure. Non-adherence was an active decision, partly based on misunderstandings of the condition and general disapproval of medication, but mostly taken in order to facilitate daily life or minimize adverse effects. Adherent patients gave less evidence of involvement in care than non-adherent patients. There was no obvious relation between reported adherence, laboratory markers of adherence and blood-pressure levels.

CONCLUSIONS

The interview is a powerful tool for ascertaining patients' concepts and behaviour. To optimize treatment of hypertension, it is important to form a therapeutic alliance in which patients' doubts and difficulties with therapy can be detected and addressed. For this, effective patient-physician communication is of vital importance.

Large tunable Rashba spin splitting of a two-dimensional electron gas in Bi2Se3

We report a Rashba spin splitting of a two-dimensional electron gas in the topological insulator Bi(2)Se(3) from angle-resolved photoemission spectroscopy. We further demonstrate its electrostatic control, and show that spin splittings can be achieved which are at least an order-of-magnitude larger than in other semiconductors. Together these results show promise for the miniaturization of spintronic devices to the nanoscale and their operation at room temperature.

Therapeutic targeting of Chk1 in NSCLC stem cells during chemotherapy

Cancer stem cell (SC) chemoresistance may be responsible for the poor clinical outcome of non-small-cell lung cancer (NSCLC) patients. In order to identify the molecular events that contribute to NSCLC chemoresistance, we investigated the DNA damage response in SCs derived from NSCLC patients. We found that after exposure to chemotherapeutic drugs NSCLC-SCs undergo cell cycle arrest, thus allowing DNA damage repair and subsequent cell survival. Activation of the DNA damage checkpoint protein kinase (Chk) 1 was the earliest and most significant event detected in NSCLC-SCs treated with chemotherapy, independently of their p53 status. In contrast, a weak Chk1 activation was found in differentiated NSCLC cells, corresponding to an increased sensitivity to chemotherapeutic drugs as compared with their undifferentiated counterparts. The use of Chk1 inhibitors in combination with chemotherapy dramatically reduced NSCLC-SC survival in vitro by inducing premature cell cycle progression and mitotic catastrophe. Consistently, the co-administration of the Chk1 inhibitor AZD7762 and chemotherapy abrogated tumor growth in vivo, whereas chemotherapy alone was scarcely effective. Such increased efficacy in the combined use of Chk1 inhibitors and chemotherapy was associated with a significant reduction of NSCLC-SCs in mouse xenografts. Taken together, these observations support the clinical evaluation of Chk1 inhibitors in combination with chemotherapy for a more effective treatment of NSCLC.

Alcohol dehydrogenase in human tissues: localisation of transcripts coding for five classes of the enzyme

Tissue distribution of the five identified classes of human alcohol dehydrogenase was studied by assessment of mRNA levels in 23 adult and four fetal tissues. Alcohol dehydrogenase of class I was found in most tissues, brain and placenta excluded, but expression levels among tissues differed widely. The distribution pattern of class III transcripts was consistent with those of housekeeping enzymes while, in contrast, class IV transcripts were found only in stomach. Transcripts of multiple length were detected for most classes and were due to different gene products arising through the use of different poly-A signals or transcription from different gene loci. Both class II and class V showed a pattern of liver-enriched expression. However, low mRNA levels were detected also in stomach, pancreas and small intestine for class II, and in fetal kidney and small intestine for class V. Significantly higher levels of class V transcripts were present in fetal liver when compared with levels in adult liver, which suggests that human class V is a predominantly fetal alcohol dehydrogenase.

Body mass index as a predictor of 1 year mortality in geriatric patients

BACKGROUND AND AIMS

The predictive value of body mass and functional capacity for 1 year mortality was examined retrospectively in 552 consecutive geriatric patients categorized in 14 diagnosis groups.

METHODS

Data on body mass index (BMI, kg/m(2)) was retrievable from 337 subjects. In 532 patients, Katz indexes of activities of daily life (ADL, A-G; A=independent, G total dependence) were registered. The mean age (+/- SD) was 81 +/- 8 years, two-thirds were women and 75% lived alone. Mortality data was obtained from the Swedish population records.

RESULTS

Thirty-six per cent of the patients had BMI values < or =43% had BMI 21-25 and 21% > 25. Less than 2% were diagnosed as malnourished. The 1 year mortalities of those with BMI < or = 20, BMI 21-25 and BMI > 25 were 48%, 29% and 18% respectively (P< 0.001). Katz ADL index was significantly worse in those with BMI > 20 as compared with those having BMI < or = 20 (Katz D and C (P< 0.01) respectively). Patients with chronic obstructive lung disease displayed the lowest BMI values, i.e. 20 +/- 4. A logistic regression analysis indicated that BMI, gender and Katz ADL index, but not age, diagnosis or marital status, were independent predictors of 1 year mortality.

CONCLUSION

Depletion may still be an overlooked problem in geriatric patients, in whom low body mass index appears to be independently associated with imminent death.

Femtosecond interatomic Coulombic decay in free neon clusters: large lifetime differences between surface and bulk

A quantitative determination of 2s vacancy lifetimes in surface and bulk atoms of free Ne clusters has been made. While for free atoms the 2s inner-valence hole has a ps lifetime, it reduces to 6+/-1 fs for cluster bulk atoms. For surface atoms, the lifetime is on average longer than 30 fs. The lifetime estimate was obtained from fits of high-resolution photoelectron spectra of Ne clusters. The shortening of the lifetime is attributed to the coordination dependent interatomic Coulombic decay, which is extremely sensitive to internuclear distances.

Nature of the tumor-associated determinant(s) of carcinoembryonic antigen

The carbohydrate moiety of carcinoembryonic antigen could be sequentially degraded by repeated cycles of periodate oxidation, reduction, and mild acid hydrolysis (Smith degradation). After three complete degradations, all fucose and sialic acid, 80% of the galactose, 65% of the mannose, and about 40% of the N-acetylglucosamine were eliminated without impairing the ability of degraded carcinoembryonic antigen to react with specific antisera against the antigen. Inhibition studies in a carcinoembryonic antigen/rabbit anti-carcinoembryonic antigen precipitating system with oligosaccharides covering previously known internal structures of glycoproteins and presumably corresponding to the internal carbohydrate region of the antigen, demonstrated that none of the compounds tested was inhibitory. Nor could any inhibitory effect on the binding of carcinoembryonic antigen to antibody against the antigen in a radioimmunoassay system be domonstrated for the carbohydrate moiety prepared by hydrazinolysis or the glyco peptide fraction isolated after papain degradation of the antigen. However, if carcinoembryonic antigen is completely reduced and alkylated, with three intrachain disulfide bonds cleaved per 10-5 g, the immunological activity is reduced to 3-5% of untreated antigen. Furthermore, treatment of the antigen with 0.5 NaOH at 20 degrees for 2 hr completely abolished its ability to react with antiserum, whereas its ability to precipitate with a series of lectins was unchanged. No release of low-molecular-weight carbohydrate orchange in sugar composition of alkali-treated antigen was observed. Our tentative conclusion is that the carbohydrate moiety of carcinoembryonic antigen does not contain the tumor-associated determinant(s).

Structural studies on the O-glycosidically linked carbohydrate chains of glucoamylase G1 from Aspergillus niger

Glucoamylase G1 from Aspergillus niger contains an unusual type of carbohydrate-protein linkage, involving mannose O-glycosidically linked to serine and threonine. The majority of the neutral oligosaccharides of glucoamylase G1 are located in a region of about 70 amino acid residues which carries about 35 oligosaccharide units [(1983) Carlsberg Res. Commun. 48, 517-527]. Structural analysis was performed on the O-linked carbohydrates of a tryptic fragment from glucoamylase G1 comprising the segment characterized by a high degree of glycosylation. The carbohydrate structures released by trifluoroacetolysis were elucidated using sugar analysis, methylation analysis, mass spectrometry, chromium trioxide oxidation, digestion with alpha-mannosidase and 1H-NMR spectroscopy. The following structures could be identified. (formula; see text)

The electronic structure of free water clusters probed by Auger electron spectroscopy

(H2O)(N) clusters generated in a supersonic expansion source with N approximately 1000 were core ionized by synchrotron radiation, giving rise to core-level photoelectron and Auger electron spectra (AES), free from charging effects. The AES is interpreted as being intermediate between the molecular and solid water spectra showing broadened bands as well as a significant shoulder at high kinetic energy. Qualitative considerations as well as ab initio calculations explain this shoulder to be due to delocalized final states in which the two valence holes are mostly located at different water molecules. The ab initio calculations show that valence hole configurations with both valence holes at the core-ionized water molecule are admixed to these final states and give rise to their intensity in the AES. Density-functional investigations of model systems for the doubly ionized final states--the water dimer and a 20-molecule water cluster--were performed to analyze the localization of the two valence holes in the electronic ground states. Whereas these holes are preferentially located at the same water molecule in the dimer, they are delocalized in the cluster showing a preference of the holes for surface molecules. The calculated double-ionization potential of the cluster (22.1 eV) is in reasonable agreement with the low-energy limit of the delocalized hole shoulder in the AES.

Mammalian alcohol dehydrogenase - functional and structural implications

Mammalian alcohol dehydrogenase (ADH) constitutes a complex system with different forms and extensive multiplicity (ADH1-ADH6) that catalyze the oxidation and reduction of a wide variety of alcohols and aldehydes. The ADH1 enzymes, the classical liver forms, are involved in several metabolic pathways beside the oxidation of ethanol, e.g. norepinephrine, dopamine, serotonin and bile acid metabolism. This class is also able to further oxidize aldehydes into the corresponding carboxylic acids, i.e. dismutation. ADH2, can be divided into two subgroups, one group consisting of the human enzyme together with a rabbit form and another consisting of the rodent forms. The rodent enzymes almost lack ethanol-oxidizing capacity in contrast to the human form, indicating that rodents are poor model systems for human ethanol metabolism. ADH3 (identical to glutathione-dependent formaldehyde dehydrogenase) is clearly the ancestral ADH form and S-hydroxymethylglutathione is the main physiological substrate, but the enzyme can still oxidize ethanol at high concentrations. ADH4 is solely extrahepatically expressed and is probably involved in first pass metabolism of ethanol beside its role in retinol metabolism. The higher classes, ADH5 and ADH6, have been poorly investigated and their substrate repertoire is unknown. The entire ADH system can be seen as a general detoxifying system for alcohols and aldehydes without generating toxic radicals in contrast to the cytochrome P450 system.

Synthesis of the disaccharide 6-O-beta-D-galactopyranosyl-2-acetamido-2-deoxy-D-galactose using immobilized beta-galactosidase

The disaccharide 6-O-beta-D-galactopyranosyl-2-acetamido-2-deoxy-D-galactose has been synthesized by transfer of the beta-D-galactopyranosyl residue from lactose to 2-acetamido-2-deoxy-D-galactose utilizing the transferase activity of beta-galactosidase from E. coli. To make the enzyme reusable, it was applied in an immobilized form covalently bound to Sepharose CL-4B. The yield of the disaccharide was about 20%, calculated on the amount of acetamido-deoxy-D-galactose added. The disaccharide could also be obtained by reversal of the hydrolytic activity of the enzyme, using D-galactose and 2-acetamido-2-deoxy-D-galactose as substrate. The yield in this reaction, however, was only 2-3% under the conditions applied.

The diagnostic accuracy of dual-view digital mammography, single-view breast tomosynthesis and a dual-view combination of breast tomosynthesis and digital mammography in a free-response observer performance study

The purpose of the present study was to compare the diagnostic accuracy of dual-view digital mammography (DM), single-view breast tomosynthesis (BT) and BT combined with the opposite DM view. Patients with subtle lesions were selected to undergo BT examinations. Two radiologists who are non-participants in the study and have experience in using DM and BT determined the locations and extents of lesions in the images. Five expert mammographers interpreted the cases using the free-response paradigm. The task was to mark and rate clinically reportable findings suspicious for malignancy and clinically relevant benign findings. The marks were scored with reference to the outlined regions into lesion localization or non-lesion localization, and analysed by the jackknife alternative free-response receiver operating characteristic method. The analysis yielded statistically significant differences between the combined modality and dual-view DM (p < 0.05). No differences were found between single-view BT and dual-view DM or between single-view BT and the combined modality.

The importance of grade 2 ischemic mitral regurgitation in coronary artery bypass grafting

OBJECTIVE

To study if grade 2 ischemic mitral regurgitation (MR) influences outcome after coronary artery bypass grafting (CABG).

METHODS

Results of all CABG patients with grade 2/4 ischemic MR operated during 1995--1998 (n = 89) were compared with all CABG patients without MR (n = 4709) during the same period. To further evaluate patients with grade 2 ischemic MR, a case-control study focusing on functional status was performed. Control patients without MR (n = 89) were matched for age, gender and left ventricular ejection fraction. All patients were interviewed regarding angina symptoms and functional status.

RESULTS

Survival according to Kaplan--Meier at 1 and 3 years were inferior in the MR group compared to all CABG patients (91 vs 96% and 84 vs 92%, respectively (P = 0.0017). However, MR patients were older (68 +/- 9 vs 65 +/- 9 years (mean +/- SD), P = 0.008) and had an inferior preoperative left ventricular ejection fraction (42 +/- 14 vs 58 +/- 14%, P < 0.0001). In the case-control study, New York Heart Association (NYHA) class and Higgins' risk score differed preoperatively between the MR group and controls. Neither 30-day mortality (4,5% in both groups) nor survival at 1 (91 vs 93%) and 3 years (84 vs 88%) differed significantly. NYHA class and angina class (Canadian Cardiovascular Society, CCS) improved similarly in both groups. Postoperatively, 62% of the patients in the MR group had reduced, 36% unchanged and 2% increased MR.

CONCLUSIONS

CABG on patients with grade 2 ischemic MR reduces angina pectoris and improves functional status to the same extent as in CABG patients without MR. Postoperative morbidity and mortality do not differ significantly between the groups. Grade of MR is reduced or unchanged after CABG in patients with grade 2 ischemic MR. The study supports an operative strategy where grade 2 ischemic mitral regurgitation is treated by CABG alone but the result do not exclude that there might be individual patients that would benefit from a valvular or annular procedure in combination with CABG. How these patients should be identified remains unclear.

Iron, zinc and folate status during pregnancy and two months after delivery

Iron, zinc and folate statuses of 45 women were determined during pregnancy around 12, 20, 28, 32 and 36 weeks, and again 2 months after delivery. Analyses of plasma ferritin, Hb, MCV, folate and zinc in plasma and whole blood were performed. Iron supplementation was recommended from mid-pregnancy but 13 of the participants did not use the iron supplements. This group had significantly decreased levels of plasma ferritin and MCV at the end of pregnancy, but none developed anemia. Two months post partum the plasma ferritin of the unsupplemented group had normalized and was in the same range as in the supplemented group. The concentrations of zinc in plasma and whole blood and the calculated levels of red cells were low even at the first examination around 12 weeks of gestation, compared with non-pregnant women. Throughout the course of pregnancy the plasma zinc levels continued to decrease, while the whole blood and red cell levels showed a significant rise. At term of gestation almost half the women had subnormal plasma folate levels (L. casei), which persisted during the post partum follow-up. The corresponding value for red cell folate was 10% below normal values at term and 30% subnormal 2 months after parturition. These findings stress the importance of extending the observation period to include also the lactating period, in order to judge the need for folate supplementation.

Development of quinolone-imipenem cross resistance in Pseudomonas aeruginosa during exposure to ciprofloxacin

Selection and regrowth of ciprofloxacin-resistant variants, which were present in low frequencies in the initial inoculum, were seen when large inocula of Pseudomonas aeruginosa were incubated with ciprofloxacin. These variants showed cross resistance to other quinolones. In 8 of 13 strains tested, ciprofloxacin selected imipenem-resistant variants in a similar way to imipenem. The opposite phenomenon of ciprofloxacin-imipenem cross resistance after exposure to imipenem was not detected. None of the ciprofloxacin-resistant variants showed cross resistance to aztreonam, piperacillin, or tobramycin. These findings indicate that widespread and uncritical use of ciprofloxacin gives a potential risk of development of resistance in P. aeruginosa not only to quinolones but also to another unrelated useful agent, imipenem. In vitro evaluation of this phenomenon in isolates from patients with P. aeruginosa infections may be justified, since strains differ in development of quinolone-imipenem cross resistance after ciprofloxacin exposure.

Activities of human alcohol dehydrogenases in the metabolic pathways of ethanol and serotonin

Alcohols and aldehydes in the metabolic pathways of ethanol and serotonin are substrates for alcohol dehydrogenases (ADH) of class I and II. In addition to the reversible alcohol oxidation/aldehyde reduction, these enzymes catalyse aldehyde oxidation. Class-I gammagamma ADH catalyses the dismutation of both acetaldehyde and 5-hydroxyindole-3-acetaldehyde (5-HIAL) into their corresponding alcohols and carboxylic acids. The turnover of acetaldehyde dismutation is high (kcat = 180 min-1) but saturation is reached first at high concentrations (Km = 30 mm) while dismutation of 5-HIAL is saturated at lower concentrations and is thereby more efficient (Km = 150 microm; kcat = 40 min-1). In a system where NAD+ is regenerated, the oxidation of 5-hydroxytryptophol to 5-hydroxyindole-3-acetic acid proceeds with concentration levels of the intermediary 5-HIAL expected for a two-step oxidation. Butanal and 5-HIAL oxidation is also observed for class-I ADH in the presence of NADH. The class-II enzyme is less efficient in aldehyde oxidation, and the ethanol-oxidation activity of this enzyme is competitively inhibited by acetate (Ki = 12 mm) and 5-hydroxyindole-3-acetic acid (Ki = 2 mm). Reduction of 5-HIAL is efficiently catalysed by class-I gammagamma ADH (kcat = 400 min-1; Km = 33 microm) in the presence of NADH. This indicates that the increased 5-hydroxytryptophol/5-hydroxyindole-3-acetic acid ratio observed after ethanol intake may be due to the increased NADH/NAD+ ratio on the class-I ADH.