A comparison of two different team models for treatment of diabetes mellitus in primary care

The importance of the nurse's role in the management of patients with type 2 diabetes has long since been emphasized. The aim of this study was to test the hypothesis that a structured organization of type 2 diabetes care, with a diabetes nurse working more independently of the general practitioner, has a significant impact on the patient's self-management and quality of care. The test consisted of 394 registered patients, all with an onset of diabetes mellitus occurring after the age of 34, at two primary health care (PHC) districts in Blekinge county in South Sweden. During one year all consultations for both doctors and nurses were analysed, and a structured telephone survey was carried out involving 364 patients who were 84 years or younger. A comparison between the two PHC centres was made regarding quality of care, frequency of consultation, patients' knowledge of their disease, and patients' self-management. The results showed that organizing care of type 2 diabetes in a structured way encourages better metabolic control in spite of less use of oral medication, and among the patients a greater knowledge of their disease and a more active self-management thus favouring implementation of local guidelines. Also, a difference was found in the patients' choice of contact with doctor or nurse regarding their diabetes and even other causes, which shifted the balance from doctor to nurse. This study provides support for organizing type 2 diabetes care in a structured way to increase the quality of care.

Associations of Fc epsilon R1-beta polymorphisms with immunoglobin E antibody responses to common inhalant allergens in a rural population

BACKGROUND

Polymorphisms within the beta subunit of the high-affinity receptor for IgE (Fc epsilon R1-beta ) on chromosome 11q13 have been related to atopy and asthma and the lymphotoxin alpha (LT alpha) gene on chromosome 6 is implicated in asthma.

OBJECTIVE

To elucidate the association of polymorphisms in the Fc epsilon R1-beta and LT alpha genes to IgE responses and asthma in a family-orientated rural population.

METHODS

A total of 461 adult farmers, who participated in an epidemiological follow-up study on respiratory symptoms among farmers on the Swedish island of Gotland, were examined. The traits assessed included serum total IgE, IgE antibody responses to 21 common inhalant allergens and asthma.

RESULTS

The 237G mutation was only detected in seven persons. Atopy was found to be associated with the RsaI-ex7 AB-genotype (OR = 1.9; P = 0.04). The RsaI-ex7 B allele had a significant influence on IgE responses to pollens and dust mites (OR = 5.5; P = 0.03 and OR = 5.2; P = 0.049, respectively). The influence of this allele was stronger when the association towards single dust mite species (Lepidoglyphus destructor) was estimated (OR = 7.1, P = 0.03) and the association increased even more when the major allergen of L. destructor (rLep d 2) was analysed (OR = 11.2, P = 0.02). These associations were independent of sex, age and smoking, and the estimates of RsaI-in2 independent of RsaI-ex7. RsaI-in2, RsaI-ex7 and LT alpha genotypes were unassociated with total serum IgE. No significant difference in the distribution of RsaI-in2, RsaI-ex7 and LT alpha genotypes was found among subjects with atopy or asthma compared to healthy controls.

CONCLUSION

This study supports the notion that polymorphisms in the Fc epsilon R1-beta gene have significant effects on IgE responsiveness. Secondly, dust mites in rural populations influence the expression of genes on chromosome 11q13.

Fewer bacterial relapses after oral treatment with norfloxacin than with ceftibuten in acute pyelonephritis initially treated with intravenous cefuroxime

This double-blind, multicentre study was performed at nine centres on a total of 171 patients who presented with fever (> 38.5 degrees C) and signs of acute pyelonephritis. All were initially treated with intravenous cefuroxime. After 2-3 d, when the fever had subsided and urinary culture had revealed growth of Gram-negative bacteria ( > 10(7) colony-forming units per litre), treatment was changed to oral administration of ceftibuten 200 mg b.i.d. or norfloxacin 400 mg b.i.d. for 10 d. The patients were followed for signs of bacterial or clinical relapse 7-14 d after the end of treatment. The initial clinical and bacteriological cure was excellent in both groups, but there were significantly fewer bacterial relapses after oral treatment with norfloxacin than with ceftibuten in acute febrile pyelonephritis initially treated with intravenous cefuroxime. The causal strain was eradicated in 75% of patients (73% of males, 76% of females) in the ceftibuten group and in 89% of patients (94% of males, 85% of females) in the norfloxacin group. The relative frequency of eradication was 0.84 (p < 0.05; 95%, confidence interval 0.74-0.97). Adverse events were reported by 47% of the patients in the ceftibuten group and by 38% in the norfloxacin group. This difference was not significant, but diarrhoea or loose stools occurred more frequently in the ceftibuten group.

An ELISA for recombinant Lepidoglyphus destructor, Lep d 2, and the monitoring of exposure to dust mite allergens in farming households

BACKGROUND

Exposure to indoor allergens, such as dust mites, has been recognized as a risk factor for sensitization and symptoms.

OBJECTIVE

To develop a two-site ELISA for the determination of Lep d 2 in the reservoir, to measure dust mite allergen exposure (Lep d 2, Der p 1, Der f 1 and Der 2) in farm households, and to investigate whether exposure to these allergens is associated with sensitization, asthma and rhinoconjunctivitis.

METHODS

Monoclonal antibodies to recombinant (r)Lep d 2 were produced with standard hybridoma technique. Dust samples from 393 households were analysed for allergen content by two-site ELISA methods.

RESULTS

A two-site Lep d 2 ELISA was developed with a detection limit of 0.09 microg/g. The assay was highly reproducible and levels of Lep d 2 showed a strong correlation with the number of Lepidoglyphus mites (r(s): 0.7; P = 0.0002). Lep d 2 was detected in 20% of the homes; levels ranged from 0.09 to 1.7 microg/g of dust. Der p 1 was recorded in 59% of the samples, ranging from 0.055 to 139 microg/g, and Der f 1 and Der 2 in 40% and 50% of the samples, ranging from 0.055 to 24.5 microg/g and 24.3 microg/g, respectively. Dermatophagoides allergens were significantly higher in mattresses than in carpets (P < 0.0001), but this difference was not observed with Lep d 2. A strong relationship between immunoglobulin (Ig)E to rLep d 2 and asthma (OR = 10.4) and rhinoconjunctivitis (OR = 7.5) was seen. Furthermore, sensitization to D. pteronyssinus was significantly associated with asthma (OR: 13.7) and rhinoconjunctivitis (OR: 5.7).

CONCLUSION

When assessing mite allergen exposure in rural homes, not only the Der p 1, Der f 1 and Der 2 allergens, but also the Lep d 2 allergen should be taken into consideration.

Tanzanian midwives' views on becoming a good resource and support person for postpartum women

OBJECTIVES

to explore midwives' views in relation to the provision of systematic postpartum care.

DESIGN

qualitative focus group study using grounded theory approach.

SETTING

Dar es Salaam, Tanzania.

PARTICIPANTS

49 nurse/midwives in five focus group discussions, each having 9-11 participants.

FINDINGS

eight categories were identified: 'reflecting', 'getting ready', 'defining abilities', 'networking', 'integrating', 'balancing', 'dealing with reality', and 'caring'. The identified core category that integrated and encapsulated all other categories was 'becoming a good resource and support person for postpartum woman'. The mediating factors found to have potential for influencing how a midwife can function in order to become a good resource and support person were: a) the structure and approach in maternal and child health services, b) midwives' knowledge, attitude and skills, c) informal sources of knowledge to parents, and d) cultural beliefs and practices.

CONCLUSION

the findings of this study provide an understanding of the way midwives feel and think about the provision of postpartum care. The findings demonstrate that midwives need support in their efforts to achieve what they consider necessary for postpartum care. Interventions for educating and supporting midwives should be targeted at enabling them to deal with all the factors that influence their role and help them to identify and use better strategies to provide quality care.

Structure of DNA polymerase delta from Saccharomyces cerevisiae

DNA polymerase delta (Pol delta) from Saccharomyces cerevisiae consists of three subunits, Pol3 (125 kDa), Pol31 (55 kDa), and Pol32 (40 kDa), present at a 1:1:1 stoichiometry in purified preparations. Previously, based on gel filtration studies of Pol delta, we suggested that the enzyme may be a dimer of catalytic cores, with dimerization mediated by the Pol32 subunit (Burgers, P. M., and Gerik, K. J. (1998) J. Biol. Chem. 273, 19756-19762). We now report on extensive gel filtration, glycerol gradient sedimentation, and analytical equilibrium centrifugation studies of Pol delta and of several subassemblies of Pol delta. The hydrodynamic parameters of these assemblies indicate that (i) Pol32 is a rod-shaped protein with a frictional ratio f/f(0) = 2.22; (ii) any complex containing Pol32 also has an extremely asymmetric shape; (iii) the results of these studies are independent of concentration (varied between 0.1-20 microm); (iv) all complexes are monomeric under the conditions studied (up to 20 microm). Moreover, a two-hybrid analysis of the Pol32 subunit did not detect a Pol32-Pol32 interaction in vivo. Therefore, we conclude that the assembly structure of Pol delta is that of a monomer.

Outpatient parenteral antibiotic therapy in patients with haematological malignancies. A pilot study of an early discharge strategy

The objectives of this study were to estimate the feasibility of a self-administration outpatient parenteral antibiotic therapy (OPAT) model. to record the complication rate and to estimate patient acceptance during the OPAT period in patients with acute leukaemia (AL) or aggressive non-Hodgkin lymphoma (NHL). Patients were trained to administer the antibiotic infusions themselves, via their central venous access device, according to a checklist and step-by-step instructions. Study-specific questionnaires were used to evaluate patient acceptance. Eleven patients [AL (n=8) and NHL (n=3), median age 51 years, range 29-661 participated in the education programme and subsequent OPAT during ten episodes of documented infection and six episodes of fever of unknown aetiology. All patients had assessment of the infectious episode and initial parenteral antibiotic therapy in the hospital before they continued self-administration at home. The median education time was 3 h (range 0.75-4.5). The patients could stay at home for 4 days (median, range; 1-12) with ongoing intravenous antibiotic therapy instead of being hospitalised. None of the patients developed recurrent fever. All patients reported that OPAT was of great value and they would favour OPAT again during subsequent antibiotic therapy. In conclusion, the results of this pilot series suggest that OPAT, in this setting, is a safe alternative during the last days of an episode of fever / infection. All patients were satisfied overall, and none was readmitted.

Effects of the levonorgestrel-releasing intrauterine system on proliferation and apoptosis in the endometrium

BACKGROUND

The levonorgestrel-releasing intrauterine system (LNg-IUS) has been shown to be effective in the management of menorrhagia. In order to evaluate the effects of LNg-IUS on endometrial proliferation and apoptosis, proliferating cell nuclear antigen (PCNA) expression, apoptosis, Fas and Bcl-2 protein expression in the endometrium were determined at the early proliferative phase of the menstrual cycle before and 3 months after LNg-IUS insertion.

METHODS

PCNA, Fas and Bcl-2 protein expression were analysed using an avidin-biotin immunoperoxidase method. Apoptosis was assessed by the terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick-end labelling (TUNEL) method.

RESULTS

PCNA, immunolocalized both in the nuclei of endometrial glands and stroma was less abundant 3 months after insertion (P < 0.05). Bcl-2 protein, immunolocalized in the cytoplasm of endometrial glands but not in the stroma, became scanty 3 months after insertion. Fas antigen, immunolocalized only in endometrial glands before insertion, became prominent in both endometrial glands and stroma 3 months after insertion. The apoptosis-positive rate of the nuclei in both endometrial glands and stroma was significantly higher 3 months after insertion relative to that before insertion (P < 0.05).

CONCLUSIONS

LNg-IUS resulted in a decrease in endometrial proliferation and an increase in apoptosis in endometrial glands and stroma. The increase in apoptosis associated with increased Fas antigen expression and decreased Bcl-2 protein expression in the endometrium may be one of the underlying molecular mechanisms by which LNg-IUS insertion causes the atrophic change of the endometrium.

Fear and social isolation as consequences of tuberculosis in VietNam: a gender analysis

SETTING

The study was conducted in four districts in different regions of Vietnam.

OBJECTIVE

To describe the socio-economic consequences of tuberculosis (TB) in Vietnam with special reference to gender differentials concerning social stigma and isolation.

DESIGN

Sixteen focus group discussions were carried out with men and women, TB patients and non-TB participants. Data was analysed using modified grounded theory technique.

RESULTS

Generally, the participants had good knowledge about TB. However, knowledge and practice were not closely related in the sense that most non-TB participants perceived that TB can be successfully cured, while patients were seriously shocked when they were told that they had TB. Male patients often worried about economic-related problems, while female patients worried about social consequences of the disease. Both in the family and the community, isolation could be subtle, but it could also be obvious and had a tendency to continue much longer than medically justified.

CONCLUSION

Information on stigma and isolation due to TB and gender differences is important for understanding patient dynamics and its effects on the disease. Tuberculosis control programmes need better understanding of the gender differences in attitudes and beliefs to improve case-detection and treatment outcome.

A hypoallergenic derivative of the major allergen of the dust mite Lepidoglyphus destructor, Lep d 2.6Cys, induces less IgE reactivity and cellular response in the skin than recombinant Lep d 2

BACKGROUND

The major allergen of the dust mite Lepidoglyphus destructor, Lep d 2, has been produced as a recombinant allergen (rLep d 2) with IgE reactivity both in vivo and in vitro. A modified form of rLep d 2 (rLep d 2.6Cys) obtained by site-directed mutagenesis has been shown to have a reduced IgE reactivity in vitro. In this study we have compared the ability of rLep d 2 and rLep d 2.6Cys to elicit positive skin prick tests and cellular responses among L. destructor-sensitized subjects.

METHODS

Seventeen subjects were skin prick-tested with rLep d 2, rLep d 2.6Cys, histamine and negative controls and 17-20 h later skin biopsy specimens were taken from the skin prick-tested sites. The biopsy specimens were stained immunohistochemically for EG2+, CD3+, CD1a+, mast cell tryptase+, and IgE+ cells. Dermal cell infiltrates were judged in hematoxylin and eosin staining. Total IgE and allergen-specific IgE were determined by CAP-RAST.

RESULTS

Compared to rLep d 2, rLep d 2.6Cys induced significantly smaller and fewer skin prick test reactions (p < 0.001) and dermal cell infiltrates (p < 0.05). Further, rLep d 2.6Cys induced fewer EG2+ cells (p < 0.001) but more tryptase+ cells (p < 0.05) than rLep d 2. A positive RAST to rLep d 2 was obtained for 88.2% of the subjects, while only 35.2% displayed a positive RAST to rLep d 2.6Cys.

CONCLUSION

This study demonstrates that rLep d 2.6Cys is less able to evoke IgE-mediated reactions and cellular responses, as measured both in skin and in serum, than rLep d 2. In the future this hypoallergenic derivative may be a promising candidate molecule for immunotherapy of L. destructor-allergic patients.

Two new male contraceptives exert their effects by depleting germ cells prematurely from the testis

The three currently available male contraceptive approaches are 1) the barrier method such as the condom, 2) hormonal methods by disrupting the pituitary-testicular axis so as to impair spermatogenesis, and 3) immunological methods by preparing vaccines against male-specific antigens. We hereby describe an alternative approach in which attachments of developing germ cells onto the seminiferous epithelium are disrupted, thereby inducing their premature release into the tubular lumen. This in turn leads to infertility. A panel of analogues based on the core structure of 1-(2,4-dichlorobenzyl)-indazole-3-carboxylic acid was synthesized. These compounds were subjected to an in vivo screening assay assessing their effects in inducing the expression of testin, a testicular marker whose expression correlates with the integrity of Sertoli-germ cell junctions. An induction of testin expression in the testis signifies a disruption of Sertoli-germ cell junctions that is followed by depletion of germ cells from the seminiferous epithelium. Two compounds, namely 1-(2,4-dichlorobenzyl)-indazole-3-carbohydrazide (AF-2364) and 1-(2,4-dichlorobenzyl)-indazole-3-acrylic acid (AF-2785), were identified that caused detachment of germ cells, in particular round and elongated spermatids, from the epithelium inducing their premature release into the tubular lumen as confirmed by histological analysis. Adult rats receiving several oral doses of either one of these compounds became infertile within 3-7 wk after the epididymal sperm reserve was exhausted. Depending on the dosing of the administered compound, rats became infertile for 4-14 wk before their fertility gradually bounced back, illustrating the reversibility and efficacy of these new compounds. Also, these compounds did not appear to impair the hypothalamus-pituitary-testicular axis because the serum levels of LH, FSH, and testosterone of the treated animals did not change significantly when compared to control rats. In addition, results of serum microchemistry illustrate that liver and kidney function was not affected in animals treated with both compounds.

Allergenic cross-reactivity between the nematode Anisakis simplex and the dust mites Acarus siro, Lepidoglyphus destructor, Tyrophagus putrescentiae, and Dermatophagoides pteronyssinus

BACKGROUND

The nematode Anisakis simplex is a common parasite on fish and other seafood. It is considered to be a food allergen and to induce IgE-mediated reactions. Allergenic cross-reactivity between A. simplex and other nematodes has been reported, as has cross-reactivity with arthropods: red mosquito larvae and German cockroach. We have here studied the allergenic relationship between A. simplex and four different dust-mite species.

METHODS

Serum samples collected from 69 farmers allergic to dust mites were analyzed for IgE to A. simplex by CAP FEIA. Allergenic cross-reactivity between A. simplex and dust mites was studied in two of the sera by CAP FEIA and immunoblotting inhibition.

RESULTS

We found that 14/69 farmers had detectable levels of IgE antibodies to A. simplex. The IgE response in CAP FEIA to A. simplex was inhibited to various degrees in the two studied sera by extracts of the dust mites Acarus siro, Lepidoglyphus destructor, Tyrophagus putrescentiae, and Dermatophagoides pteronyssinus. In the reverse inhibition experiment, extract of A. simplex inhibited the response in both sera to A. siro and T. putrescentiae, but not to L. destructor. The IgE binding to D. pteronyssinus was inhibited in one of the two sera. In blotting inhibition experiments, the IgE binding to several allergens in A. simplex was inhibited by each of the four mite extracts, especially by A. siro and T. putrescentiae, which completely inhibited the IgE binding to several allergens.

CONCLUSION

The results show allergenic cross-reactivity between several allergens in A. simplex and four dust-mite species. The clinical significance of this cross-reactivity remains to be evaluated.

Interactions between the Werner syndrome helicase and DNA polymerase delta specifically facilitate copying of tetraplex and hairpin structures of the d(CGG)n trinucleotide repeat sequence

Werner syndrome (WS) is an inherited disorder characterized by premature aging and genomic instability. The protein encoded by the WS gene, WRN, possesses intrinsic 3' --> 5' DNA helicase and 3' --> 5' DNA exonuclease activities. WRN helicase resolves alternate DNA structures including tetraplex and triplex DNA, and Holliday junctions. Thus, one function of WRN may be to unwind secondary structures that impede cellular DNA transactions. We report here that hairpin and G'2 bimolecular tetraplex structures of the fragile X expanded sequence, d(CGG)(n), effectively impede synthesis by three eukaryotic replicative DNA polymerases (pol): pol alpha, pol delta, and pol epsilon. The constraints imposed on pol delta-catalyzed synthesis are relieved, however, by WRN; WRN facilitates pol delta to traverse these template secondary structures to synthesize full-length DNA products. The alleviatory effect of WRN is limited to pol delta; neither pol alpha nor pol epsilon can traverse template d(CGG)(n) hairpin and tetraplex structures in the presence of WRN. Alleviation of pausing by pol delta is observed with Escherichia coli RecQ but not with UvrD helicase, suggesting a concerted action of RecQ helicases and pol delta. Our findings suggest a possible role of WRN in rescuing pol delta-mediated replication at forks stalled by unusual DNA secondary structures.

Roles of yeast DNA polymerases delta and zeta and of Rev1 in the bypass of abasic sites

Abasic (AP) sites are one of the most frequently formed lesions in DNA, and they present a strong block to continued synthesis by the replicative DNA machinery. Here we show efficient bypass of an AP site by the combined action of yeast DNA polymerases delta and zeta. In this reaction, Poldelta inserts an A nucleotide opposite the AP site, and Polzeta subsequently extends from the inserted nucleotide. Consistent with these observations, sequence analyses of mutations in the yeast CAN1s gene indicate that A is the nucleotide inserted most often opposite AP sites. The nucleotides C, G, and T are also incorporated, but much less frequently. Enzymes such as Rev1 and Poleta may contribute to the insertion of these other nucleotides; the predominant role of Rev1 in AP bypass, however, is likely to be structural. Steady-state kinetic analyses show that Polzeta is highly inefficient in incorporating nucleotides opposite the AP site, but it efficiently extends from nucleotides, particularly an A, inserted opposite this lesion. Thus, in eukaryotes, bypass of an AP site requires the sequential action of two DNA polymerases, wherein the extension step depends solely upon Polzeta, but the insertion step can be quite varied, involving not only the predominant action of the replicative DNA polymerase, Poldelta, but also the less prominent role of various translesion synthesis polymerases.

Effects of an experimental infection with Actinobacillus pleuropneumoniae on the interferon-alpha and interleukin-6 producing capacity of porcine peripheral blood mononuclear cells stimulated with bacteria, virus or plasmid DNA

The effect of a bacterial infection on interferon-alpha (IFN-alpha) and interleukin-6 (IL-6) production by porcine cells was studied in specific pathogen-free (SPF) pigs, infected intranasally with Actinobacillus pleuropneumoniae serotype 2. Three experimental groups of five pigs were used: infected non-treated pigs, infected pigs that were treated with enrofloxacin at disease onset, and non-infected, non-treated control pigs. Blood samples were collected from all pigs on the day of infection and on days 1, 4, 7, 13 and 17 post-infection. Sera were analysed for presence of antibodies to A. pleuropneumoniae and for the cytokines IL-6 and IFN-alpha. Ability to produce these cytokines was tested in vitro using whole blood cultures stimulated with inactivated virus (Aujeszky's disease virus infected porcine kidney cells (ADV/PK-15)), inactivated bacteria (A. pleuropneumoniae) or bacterial plasmid (pcDNA3). All cytokine inducers were used neat or pre-incubated with the transfectious agent lipofectin. IL-6 appeared in the serum of all infected non-treated animals but no IFN-alpha was found in the serum of any of the experimental pigs. Accordingly, the bacteria induced a substantial IL-6 but hardly any IFN-alpha production when tested in vitro. However, following incubation with lipofectin, the inactivated bacteria as well as pcDNA3 became efficient inducers of IFN-alpha in whole blood cultures. The increased IFN-alpha production, previously recorded in vitro during the acute phase of infection with A. pleuropneumoniae, was confirmed using lipofected plasmid DNA and it was indicated that leukocytes obtained from infected but apparently cured animals also exhibited an increased production of IFN-alpha. Thus, even mild/sub-clinical bacterial infections may affect cytokine production in pigs.

[The Gothenburg study of women and alcohol: low occurrence of abuse--increase appears to have abated]

Prevalence of alcohol dependence and abuse (ADA) was determined in a cohort of women selected by stratified random sampling from the general population in Gothenburg. A questionnaire was administered to 3,130 women and 399 were interviewed. Questions were asked about social background, living conditions, family and working life. Volume and frequency of alcohol intake were recorded, and diagnoses were made according to DSM-III. We found that the one-year prevalence of ADA was 1.5 percent and the life time prevalence 3.3 percent. In a follow-up five years after base-line, the prevalence of ADA was unchanged, while indicators of high alcohol consumption and high episodic drinking showed reduced levels of problem drinking.

Cross-reactivity studies of a new group 2 allergen from the dust mite Glycyphagus domesticus, Gly d 2, and group 2 allergens from Dermatophagoides pteronyssinus, Lepidoglyphus destructor, and Tyrophagus putrescentiae with recombinant allergens

BACKGROUND

Dust mites are important inducers of allergic disease. Group 2 allergens are recognized as major allergens in several mite species, including Dermatophagoides pteronyssinus, Lepidoglyphus destructor, and Tyrophagus putrescentiae. No allergens have thus far been characterized on the molecular level from the dust mite Glycyphagus domesticus.

OBJECTIVE

We sought to examine the cross-reactivity among group 2 allergens of G domesticus, L destructor, T putrescentiae, and D pteronyssinus.

METHODS

A group 2 allergen from G domesticus, Gly d 2, was cloned and expressed as a recombinant protein. Cross-reactivity between Gly d 2 and 3 other group 2 allergens, Lep d 2, Tyr p 2, and Der p 2, was studied by using individual sera and a serum pool RAST-positive to G domesticus, L destructor, T putrescentiae, and D pteronyssinus. Recombinant allergens were used as inhibitors of IgE binding in immunoblotting experiments. Molecular modeling on the basis of the Der p 2 structure was carried out for Gly d 2, Lep d 2, and Tyr p 2.

RESULTS

Two cDNAs encoding isoforms of Gly d 2 were isolated, but only the Gly d 2.02 isoform was used in this study. Sixteen of 17 subjects had IgE to Gly d 2. The protein sequence of Gly d 2 revealed 79% identity to Lep d 2 and 46% and 41% identity to Tyr p 2 and Der p 2, respectively. Extensive cross-reactivity was demonstrated among Gly d 2, Lep d 2, and Tyr p 2, but little cross-reactivity was found between these allergens and Der p 2. According to the tertiary structure of Der p 2 and 3-dimensional models of Gly d 2, Lep d 2, and Tyr p 2, differences reside mainly in surface-exposed residues.

CONCLUSION

Gly d 2 showed high sequence homology to Lep d 2. Cross-reactivity was observed between Gly d 2, Lep d 2, and Tyr p 2, but only limited cross-reactivity was demonstrated between these 3 allergens and Der p 2.

Effects of N-acetylcysteine on pulmonary macrophage activity after intestinal ischemia and reperfusion in rats / with invited commentaries

BACKGROUND/AIMS

Intestinal ischemia and reperfusion (I/R) is considered to be a critical and triggering event in the development of distal organ dysfunction after a variety of insults. It appears that activated leukocytes, especially polymorphonuclear granulocytes (PMNs), and reactive oxygen species are important mediators in the process. In the present study, the aim was to evaluate the behavior of pulmonary macrophages, acute lung injury and pulmonary endothelial permeability after intestinal I/R, together with potential alterations in pulmonary endothelial and epithelial ultrastructure and cellular membrane system integrity.

METHODS

Intestinal ischemia for 40 min was followed by reperfusion for 12 h in the rat. Macrophage uptake of radiolabeled bacteria, levels of pulmonary blood content assessed by radiolabeled red blood cells and pulmonary endothelial permeability of radiolabeled albumin, as well as pulmonary endothelial and epithelial ultrastructure and cellular membrane system integrity by the use of scanning electron microscopy and a tracer was evaluated after 12 h reperfusion. Treatment with the free radical scavenger N-acetylcysteine (NAC) administered prior to reperfusion was evaluated.

RESULTS

Overactivation of pulmonary macrophages was noted after intestinal I/R, as was a significant decrease in pulmonary blood content. No increase in pulmonary albumin leakage or increase in pulmonary water content was found after intestinal I/R as compared to controls. Treatment with NAC prevented against intestinal I/R-induced overactivation of pulmonary macrophages and a decrease in pulmonary blood content.

CONCLUSION

Reactive oxygen species may be involved in the regulation of pulmonary macrophage function and pulmonary circulation after intestinal I/R.

A new class of symmetric bisbenzimidazole-based DNA minor groove-binding agents showing antitumor activity

The synthesis and evaluation of the novel head-to-head bisbenzimidazole compound 2,2-bis[4'-(3' '-dimethylamino-1' '-propyloxy)phenyl]-5,5-bi-1H-benzimidazole is described. An X-ray crystallographic study of a complex with the DNA dodecanucleotide sequence d(CGCGAATTCGCG) shows the compound bound in the A/T minor groove region of a B-DNA duplex and that the head-to-head bisbenzimidazole motif hydrogen-bonds to the edges of all four consecutive A:T base pairs. The compound showed potent growth inhibition with a mean IC(50) across an ovarian carcinoma cell line panel of 0.31 microM, with no significant cross-resistance in two acquired cisplatin-resistant cell lines and a low level of cross-resistance in the P-glycoprotein overexpressing acquired doxorubicin-resistant cell line. Studies with the hollow fiber assay and in vivo tumor xenografts showed some evidence of antitumor activity.

The plasmid pcDNA3 differentially induces production of interferon-alpha and interleukin-6 in cultures of porcine leukocytes

An adjuvant effect of invertebrate DNA has been attributed to its relative high frequency of unmethylated CpG dinucleotides. Here we describe the interferon-alpha (IFN-alpha) and interleukin-6 (IL-6) inducing properties of a commonly used eukaryotic expression vector, pcDNA3, in porcine leukocytes. The magnitude of the cytokine response was compared to that induced by the synthetic ds RNA analogue poly(I):poly(C), inactivated preparations of Aujeszky's disease virus (ADV) and the Gram-negative bacteria Actinobacillus pleuropneumoniae. The plasmid, as well as poly(I):poly(C), required lipofectin to induce IFN-alpha production whereas both preparations induced IL-6 irrespective of preincubation with lipofectin. However, the nucleic acid-induced levels of IL-6 were low compared to those induced by A. pleuropneumoniae. The IFN-alpha response elicited by pcDNA3 in the presence of lipofectin was as high as, or higher than that induced by ADV. Interestingly, also A. pleuropneumoniae induced a substantial production of IFN-alpha when preincubated with lipofectin. Plasmid expression was not necessary for induction of IFN-alpha. Furthermore, the IFN-alpha inducing capacity of pcDNA3 was not reduced when the two predicted immunostimulatory sequences 5'AACGTT3' were deleted. Nor did the ability of the plasmid to induce IFN-alpha production decrease when the ampicillin resistance (ampR) gene was replaced with the kanamycin resistance (kanR) gene. However, methylation of all cytidines in CpG dinucleotides of pcDNA3 abolished the IFN-alpha inducing capacity. These in vitro results indicate an immunomodulatory role of bacterial DNA also in the pig. Unmethylated CpG dinucleotides are crucial for induction of IFN-alpha by the plasmid, but other CpG motifs than those within the 5'AACGTT3' sequences of the ampR gene contribute to this induction in porcine cells.

Crystal structure of saccharopine reductase from Magnaporthe grisea, an enzyme of the alpha-aminoadipate pathway of lysine biosynthesis

BACKGROUND

The biosynthesis of the essential amino acid lysine in higher fungi and cyanobacteria occurs via the alpha-aminoadipate pathway, which is completely different from the lysine biosynthetic pathway found in plants and bacteria. The penultimate reaction in the alpha-aminoadipate pathway is catalysed by NADPH-dependent saccharopine reductase. We set out to determine the structure of this enzyme as a first step in exploring the structural biology of fungal lysine biosynthesis.

RESULTS

We have determined the three-dimensional structure of saccharopine reductase from the plant pathogen Magnaporthe grisea in its apo form to 2.0 A resolution and as a ternary complex with NADPH and saccharopine to 2.1 A resolution. Saccharopine reductase is a homodimer, and each subunit consists of three domains, which are not consecutive in amino acid sequence. Domain I contains a variant of the Rossmann fold that binds NADPH. Domain II folds into a mixed seven-stranded beta sheet flanked by alpha helices and is involved in substrate binding and dimer formation. Domain III is all-helical. The structure analysis of the ternary complex reveals a large movement of domain III upon ligand binding. The active site is positioned in a cleft between the NADPH-binding domain and the second alpha/beta domain. Saccharopine is tightly bound to the enzyme via a number of hydrogen bonds to invariant amino acid residues.

CONCLUSIONS

On the basis of the structure of the ternary complex of saccharopine reductase, an enzymatic mechanism is proposed that includes the formation of a Schiff base as a key intermediate. Despite the lack of overall sequence homology, the fold of saccharopine reductase is similar to that observed in some enzymes of the diaminopimelate pathway of lysine biosynthesis in bacteria. These structural similarities suggest an evolutionary relationship between two different major families of amino acid biosynthetic pathway, the glutamate and aspartate families.