Glycosylation site Asn168 is important for slow in vivo clearance of recombinant human diamine oxidase heparin-binding motif mutants

Elevated plasma and tissues histamine concentrations can cause severe symptoms in mast cell activation syndrome, mastocytosis or anaphylaxis. Endogenous and recombinant human diamine oxidase (rhDAO) can rapidly and completely degrade histamine, and administration of rhDAO represents a promising new treatment approach for diseases with excess histamine release from activated mast cells. We recently generated heparin-binding motif mutants of rhDAO with considerably increased in vivo half-lives in rodents compared with the rapidly cleared wildtype protein. Herein, we characterize the role of an evolutionary recently added glycosylation site asparagine 168 in the in vivo clearance and the influence of an unusually solvent accessible free cysteine 123 on the oligomerization of diamine oxidase (DAO). Mutation of the unpaired cysteine 123 strongly reduced oligomerization without influence on enzymatic DAO activity and in vivo clearance. Recombinant hDAO produced in ExpiCHO-S™ cells showed a 15-fold reduction in the percentage of glycans with terminal sialic acid at Asn168 compared with Chinese hamster ovary (CHO)-K1 cells. Capping with sialic acid was also strongly reduced at the other glycosylation sites. The high abundance of terminal mannose and N-acetylglucosamine residues in the four glycans expressed in ExpiCHO-S™ cells compared with CHO-K1 cells resulted in rapid in vivo clearance. Mutation of Asn168 or sialidase treatment also significantly increased clearance. Intact N-glycans at Asn168 seem to protect DAO from rapid clearance in rodents. Full processing of all glycoforms is critical for preserving the improved in vivo half-life characteristics of the rhDAO heparin-binding motif mutants.

Prevalence and time course of arrhythmia-induced cardiomyopathy in patients with newly diagnosed heart failure and concomitant tachyarrhythmia – the TACHY-HF pilot trial

Background

Arrhythmias may often be a result of heart failure, but they can also cause left-ventricular systolic dysfunction (LVSD), thereby presenting as arrhythmia-induced cardiomyopathy (AIC). AIC-diagnosis is established retrospectively when LVSD normalizes or improves significantly over time following rhythm restoration. However, the prevalence and most importantly the time course of this relevant disease remain unclear and hence merit investigation to enable the correct diagnosis.

Purpose

Therefore, our aim was to evaluate a) the occurrence of AIC in this clinical relevant cohort of patients with newly diagnosed and otherwise unexplainable LVSD and concomitant tachycardia and b) the time needed to fulfill the diagnostic criteria of AIC in order to facilitate a diagnostic algorithm.

Method

We prospectively screened patients hospitalized for newly diagnosed and otherwise unexplainable LVSD (i.e. left ventricular ejection fraction (LVEF) <50%) and coexisting tachyarrhythmia (atrial fibrillation/flutter + heart rate (HR) >100/min) in 3 cardiological centers. Coronary angiography and cardiac magnetic resonance imaging were performed to exclude other causes for LVSD. Patients underwent a rhythm control strategy in accordance to the local clinical pathways. LVEF was assessed by echocardiography at presentation and at follow-up (FU) visits after 2, 4, and 6 months. Patients who lost sinus rhythm (SR) during FU were excluded. Patients with any increase of ≥15% in absolute EF or an EF ≥50% with an improvement of ≥10% after 6 months of FU were assigned to the AIC-group, which is a common definition of AIC. All others were assigned to an idiopathic DCM-group as final comparator.

Results

68 patients were eligible, 18 of them were excluded: 1 lost to follow-up, 1 PCI, 2 COVID-19, 1 diagnosed cancer, 1 withdraw consent and 12 lost SR. Thus, our sample consists of a total of 50 patients. At presentation, mean±SD HR was 121±17/min. After rhythm therapy, HR normalized (67±10/min) and LVEF increased in both groups, see fig. 1. Surprisingly, only 9 patients did not fulfill the AIC-criteria in this specific collective resulting in a prevalence of 82% (95%-CI: 68% – 92%). This high prevalence of AIC underlines the importance of the disease. 2 and 4 months after rhythm intervention, 58% and 73% of patients fulfilled AIC-criteria (fig. 2). The sensitivity for detection of AIC by echocardiographic LVEF-measurement at months 2 and 4 of FU was 65% and 86% with a specificity of 100%, emphasizing that a FU of 6 months is necessary to certainly distinguish between AIC and idiopathic DCM.

Conclusion

The prevalence of AIC in patients with newly diagnosed and otherwise unexplainable LVSD with concomitant tachycardia is 82%. Analysis of the time course of AIC clearly suggests that the final diagnosis cannot be established before 6 months after successful rhythm restoration. These results may help to improve diagnosis of AIC in daily clinical practice.

Funding Acknowledgement

Type of funding sources: None.

Heparin-binding motif mutations of human diamine oxidase allow the development of a first-in-class histamine-degrading biopharmaceutical

Background

Excessive plasma histamine concentrations cause symptoms in mast cell activation syndrome, mastocytosis, or anaphylaxis. Anti-histamines are often insufficiently efficacious. Human diamine oxidase (hDAO) can rapidly degrade histamine and therefore represents a promising new treatment strategy for conditions with pathological histamine concentrations.

Methods

Positively charged amino acids of the heparin-binding motif of hDAO were replaced with polar serine or threonine residues. Binding to heparin and heparan sulfate, cellular internalization and clearance in rodents were examined.

Results

Recombinant hDAO is rapidly cleared from the circulation in rats and mice. After mutation of the heparin-binding motif, binding to heparin and heparan sulfate was strongly reduced. The double mutant rhDAO-R568S/R571T showed minimal cellular uptake. The short α-distribution half-life of the wildtype protein was eliminated, and the clearance was significantly reduced in rodents.

Conclusions

The successful decrease in plasma clearance of rhDAO by mutations of the heparin-binding motif with unchanged histamine-degrading activity represents the first step towards the development of rhDAO as a first-in-class biopharmaceutical to effectively treat diseases characterized by excessive histamine concentrations in plasma and tissues.

Funding

Austrian Science Fund (FWF) Hertha Firnberg program grant T1135 (EG); Sigrid Juselius Foundation, Medicinska Understödsförening Liv och Hälsa rft (TAS and SeV).

Human diamine oxidase cellular binding and internalization in vitro and rapid clearance in vivo are not mediated by N-glycans but by heparan sulfate proteoglycan interactions

Human diamine oxidase (hDAO) rapidly inactivates histamine by deamination. No pharmacokinetic data are available to better understand its potential as a new therapeutic modality for diseases with excess local and systemic histamine, like anaphylaxis, urticaria or mastocytosis. After intravenous administration of recombinant hDAO to rats and mice, more than 90% of the dose disappeared from the plasma pool within 10 min. Human DAO did not only bind to various endothelial and epithelial cell lines in vitro, but was also unexpectedly internalized and visible in granule-like structures. The uptake of rhDAO into cells was dependent on neither the asialoglycoprotein-receptor (ASGP-R) nor the mannose receptor (MR) recognizing terminal galactose or mannose residues, respectively. Competition experiments with ASGP-R and MR ligands did not block internalization in vitro or rapid clearance in vivo. The lack of involvement of N-glycans was confirmed by testing various glycosylation mutants. High but not low molecular weight heparin strongly reduced the internalization of rhDAO in HepG2 cells and HUVECs. Human DAO was readily internalized by CHO-K1 cells, but not by the glycosaminoglycan- and heparan sulfate-deficient CHO cell lines pgsA-745 and pgsD-677, respectively. A docked heparin hexasaccharide interacted well with the predicted heparin binding site 568RFKRKLPK575. These results strongly imply that rhDAO clearance in vivo and cellular uptake in vitro is independent of N-glycan interactions with the classical clearance receptors ASGP-R and MR, but is mediated by binding to heparan sulfate proteoglycans followed by internalization via an unknown receptor.

Simple, sensitive and specific quantification of diamine oxidase activity in complex matrices using newly discovered fluorophores derived from natural substrates

Objective

To measure diamine oxidase (DAO) activity with high sensitivity in complex matrices like plasma or tissue extracts radioactive putrescine or horseradish peroxidase (HRP)/hydrogen peroxide (H₂O₂) coupling must be used. The use of radioactive material should be avoided and HRP/H₂O₂ coupling is compromised by antioxidants.

Methods and results

Condensation of ortho-aminobenzaldehyde (oABA) with delta-1-pyrroline and delta-1-piperideine, the autocyclization products of the DAO-oxidized natural substrates putrescine and cadaverine, generates new quinazoline fluorophores with absorption and excitation maxima of 430 and 460 nm, respectively, and peak emission at 620 nm. Fluorescent-based detection limits are 20–40 times lower compared to absorption measurements. This assay can be used to measure DAO activity in human plasma after spiking recombinant human (rh)DAO, in rat plasma after intravenous rhDAO administration, in pregnancy plasma and in tissue extracts of DAO wild-type and knock-out mice. Using rat plasma the correlation between rhDAO activity and ELISA data is 99%. Human and rat plasma without DAO spiking and tissue extracts from DAO knock-out mice showed stable and low fluorescence in the presence of high substrate concentrations.

Conclusions

Incubation of DAO with the natural substrates putrescine and cadaverine and oABA generates novel fluorophores increasing the detection limit compared to absorption measurements at least tenfold. This simple, sensitive and specific assay allows the non-radioactive quantification of DAO activity in complex matrices like plasma and tissue extracts without interference by antioxidants.

Electronic supplementary material

The online version of this article (10.1007/s00011-020-01359-5) contains supplementary material, which is available to authorized users.

Predictors for delayed linguistic skills in very preterm infants

BACKGROUND

Preterm-born children are at higher risk for impaired linguistic abilities than are their term-born peers. The aim of the current study was to determine early predictors for delayed linguistic skills in very preterm-born preschool children.

METHODS

Between January 2005 and November 2010 all very preterm infants born at < 32 weeks gestation in Tyrol were prospectively enrolled (n = 421); 248 of them had a detailed examination at the age of five years including cognitive assessment (Wechsler Preschool and Primary Scale of Intelligence, third edition (WPPSI-III) or Snijders-Oomen Nonverbal Intelligence Tests (SON-R)) as well as a screening test for language skills (Bielefelder screening for early diagnosis of reading problems and weak spelling (BISC)). The association between pre-and postnatal factors and poor performance on the BISC assessment was analyzed by means of logistic regression analysis.

RESULTS

Of the 248 children 79 (31.8%) showed delayed literacy precursor skills. Male sex, gestational age, retinopathy of prematurity (ROP) grades 3-4 and low maternal education were predictive for delayed linguistic skills at 5 years of age in the multivariate analysis.

CONCLUSION

This study identified predictors for delayed literacy precursor skills. These data support the finding that in very preterm infants pre-and perinatal as well as sociodemographic factors account for linguistic skills in the preschool period.

Impact assessment of tail-vein injection in mice using a modified anaesthesia induction chamber versus a common restrainer without anaesthesia

Intravenous (IV) administration in mice is predominantly performed via the lateral tail veins. The technique requires adequate training before it can be used safely and routinely. A novel anaesthesia induction chamber has been developed to simplify the treatment and to facilitate IV injection in mice, particularly for untrained personnel. We have assessed the benefits of the chamber in refining IV injection in isoflurane-anaesthetized mice in direct comparison with the common restrainer method on conscious animals. The body weight, nesting behaviour and concentrations of faecal corticosterone metabolites were taken as indicative of distress induced by the various procedures. The results suggest that both methods of tail-vein injection induce similar levels of momentary stress in the animals, revealed by a short-term increase in the levels of stress hormone metabolites in faeces. A temporary reduction of body weight was observed after IV injection under isoflurane anaesthesia but not for conscious mice injected in the common restrainer. We conclude that the severity of tail-vein injection in mice is 'mild' for both methods. There was no evidence that refining the procedure by using isoflurane anaesthesia in the induction chamber was associated with any benefit.

Bulimia from a gynecological view: hormonal changes

Gynecological problems are one of the most frequent somatic complications of eating disorders. The purpose of the present study was to assess the role of improper eating habits in the aetiology of menstrual disturbances, anovulation and hormonal related changes. Bulimia nervosa is the focus of attention since amenorrhea is considered a diagnostic criterium in anorexia nervosa. Subjects of the BITE (Bulimia Investigation Test, Edinburgh) test who were infertile were studied (n = 58) In the studied population there were 6 cases of clinical and 8 cases of subclinical bulimia nervosa. Symptoms and severity subscales of the BITE test significantly correlated with body mass index (p = 0.003). All 14 patients suffering from clinical and subclinical bulimia nervosa had pathologically low FSH and LH hormone levels. In those with clinical bulimia nervosa (n = 6) we diagnosed 4 cases of multicystic ovary (MCO) and in the eating disorder not otherwise specified (EDNOS) group (n = 22) there were 2 cases of MCO and 5 cases of polycystic ovary syndrome (PCOS). The results suggest that unsatisfactory nutrition (binges and "crash diet") in bulimia nervosa results in hormonal dysfunction, menstrual disturbances and infertility. The authors question the necessity for immediately estrogen replacement: they consider the reversibility of the hormonal status by early treatment of eating disorders is more appropriate. Excessive use of hormonal contraceptives in therapy has to be questioned.

Increased aldosterone levels in a model of type 2 diabetes mellitus

BACKGROUND

Aldosterone is an important mediator of cardiovascular and renal remodeling. Type II diabetes mellitus leads to renal and cardiac end organ damage. We investigated the renin-angiotensin-aldosterone system in a model of type 2 diabetes mellitus with known diabetic nephropathy and cardiac remodeling, the Zucker Diabetic Fatty rat with and without ACE-inhibition (ZDF and ZDF+ACE-I) and its control, the Zucker Lean (ZDL) rat.

METHODS

Male animals were studied from an age of 7-24 weeks. At ages 7, 14, 17, 20, and 23 weeks, urinary excretion of aldosterone-glucuronide and potassium was assessed. ACE-inhibition with ramipril was started orally at week 13 (1 mg/kg/d). At the end of the study rats were sacrificed and plasma aldosterone concentration and plasma renin activity were measured. Aldosterone synthase (CYP11B2) mRNA expression in the adrenals, kidney, heart and adipose tissue was assessed by real-time PCR. Urinary albumin excretion as marker for diabetic nephropathy was measured in metabolic cages and correlated to aldosterone.

RESULTS

Plasma aldosterone concentration and aldosterone-glucuronide was significantly elevated in ZDF rats, and significantly reduced by ACE-inhibiton. In contrast, plasma renin activity was significantly reduced in ZDF rats and normalized by ACE-inhibition. The urinary aldosterone correlated significantly to albuminuria. Adrenal CYP11B2 expression was not significantly higher in ZDF rats. CYP11B2 mRNA was not detected in the kidney, heart and adipose tissue.

CONCLUSION

In ZDF rats, urinary and plasma aldosterone levels were elevated despite reduced plasma renin activity. The reversible effect of ACE-inhibition shows that the up-regulation of aldosterone must be dependent of the renin-angiotensin-system in this type II diabetes model. The correlation between aldosterone and diabetic nephropathy suggests a clinical relevance of this observation.

In-vitro-Untersuchung der Mikrostruktur von handelsüblichen ophthalmologischen Suspensionen mittels HRT-II Rostock Cornea Modul

BACKGROUND

To investigate the particles of commercially used ophthalmic suspensions with the HRT II Rostock Cornea Module and to compare them with particle parameters given in the literature.

METHODS

Software-aided analysis was carried out for the suspensions brinzolamide 1%, betaxolol HCl 0.25%, dexamethasone phosphate 0.1% and prednisolone acetate 0.5%, including measurements of length, area and circumference and calculation of ellipticity and shape factor (SF).

RESULTS

Particle characteristics (SF and ellipticity) of different suspensions demonstrated that the particles are not spherical. Significant aggregation affinity of prednisolone acetate particles was observed.

CONCLUSION

Exact and reproducible in vitro microstructural examination of ophthalmic suspensions was possible due to the high resolution of the HRT II Rostock Cornea Module.

Exanthema and acute anuric renal failure

A 15-year-old girl with a history of Kawasaki disease was admitted to our nephrological department due to acute renal failure. Despite antibiotic therapy because of fever and the symptoms of a pharyngitis in the last few days, the girl showed persisting fever and developed arthralgias, an exanthema and a rising serum creatinine as well as anuria. A wide variety of differential diagnoses has to be thought of because of the history of the Kawasaki disease (symptoms like fever, pharyngitis, exanthema and arthralgia), i.e. hemolytic-uremic syndrome, vasculitis, ascending infection, postinfection glomerulonephritis. In consideration of etiologically unclear "rapidly progressive renal failure" with anuria and thrombocytopenia an immediate renal biopsy was done and revealed a severe drug induced acute interstitial nephritis. Due to this diagnosis we treated the patient with corticosteroids. Within 4 weeks serum creatinine declined to 1.8 mg/dl but did not normalize.

Konfokale In-vivo-Hornhautmikroskopie nach Keratoplastik

BACKGROUND

Seven eyes with clear grafts after penetrating keratoplasty were examined with in vivo confocal corneal microscopy in 1999. Our aim was the confocal microscopic investigation of the subclinical changes in clear grafts after long-term follow-up.

METHODS

The preoperative diagnoses were keratoconus (two), granular corneal dystrophy (two), pseudophakic bullous keratopathy due to ACL (two), and corneal ulcer (one). The epithelium, corneal nerves, keratocytes of the anterior and posterior stroma, and endothelium were evaluated with confocal microscopy.

RESULTS

Mean density of basal epithelial cells was 3928+/-378 cells/mm(2) at 15 months and 3284+/-565 cells/mm(2) at 66 months postoperatively. At 15 months the keratocyte density was 750+/-113 cells/mm(2) in the anterior stroma and 601+/-98 cells/mm(2) in the posterior stroma, at 66 months 383+/-53 cells/mm(2) in the anterior stroma and 411+/-98 cells/mm(2) in the posterior stroma. Endothelial cell density decreased from 1719+/-576 cells/mm(2) (15 months) to 965+/-272 cells/mm(2) (66 months).

CONCLUSIONS

In the follow-up period a significant decrease of keratocyte and endothelial cell density was detectable with confocal microscopy. The clinical importance of our findings must be clarified with further examinations on more patients.

[Unilateral ptosis in the background of unilateral corneal arcus lipoides -- a case report]

BACKGROUND

Arcus lipoides corneae is a common bilateral degenerative disorder with ageing but only rarely occurs unilaterally. Clinically visible cream-coloured ring-shaped corneal opacities are caused by excessive lipoid deposits in the corneal stroma. Our aim is to discuss theoretical aspects of the possible impact and pathomechanism of unilateral ptosis in unilateral arcus lipoides.

CASE REPORT

The authors report the case of a 70-year-old female patient who was treated for chronic pancreatitis and hyperlipoproteinemia. She had congenital ptosis on the left side, and an arcus lipoides corneae in her left eye. The patient underwent extracapsular cataract extraction, and irregular high-grade astigmatism developed. An irregularity of the wound healing was apparent from the keratometric values, which decreased after removal of the corneal sutures.

CONCLUSION

The known etiological factors of unilateral arcus lipoides, like contralateral stenosis of the internal carotid artery, traumatic or iatrogenic hypotony, chronic iridocyclitis of the eye were absent in our patient.

Obstacles in the diagnosis and treatment of syphilitic amyotrophy

The authors describe a case of syphilitic amyotrophy in a 37-year-old man presenting with subacute progressive painless weakness in the right arm. Syphilitic amyotrophy is still an existing differential diagnosis of painless and progressive weakness. The authors explore potential obstacles in the diagnostic workup and finding of adequate therapy.

Further phenols and polyacetylenes from the rhizomes of Atractylodes lancea and their anti-inflammatory activity

From the rhizomes of Atractylodes lancea, 2-[(2'E)-3',7'-dimethyl-2',6'-octadienyl]-4-methoxy-6-methylphenol (1) was isolated as a new natural product. The compound showed strong inhibitory effects on 5-lipoxygenase (5-LOX) and cyclooxygenase-1 (COX-1), but exhibited only weak antioxidative activities [IC50 = 0.1 microM (5-LOX), 2 microM (COX-1), 9 microM (PMN/FMLP), 28 microM (PMNIOZ)]. Moreover, five new acetylenes were isolated and elucidated as (3Z,5E,11E)-tridecatriene-7,9-diynyl-1-O-(E)-ferulate (2), erythro-(1,3Z,11E)-tridecatriene-7,9-diyne-5,6-diyl diacetate (3), (1Z)-atractylodin (4), (1Z)-atractylodinol (5), (1Z)-acetylatractylodinol (6) plus the known (4E,6E,12E)-tetradecatriene-8,10-diyne-1,3-diyl diacetate (7). Among the acetylenes, only 2 showed strong inhibition of 5-LOX and COX-1 activity (IC50 (5-LOX) = 3 microM, IC50 (COX-1) = 1 microM). In addition, the fatty acids linoleic acid, oleic acid and palmitic acid with previously established 5-LOX-/COX-1 inhibitory actions were identified as major constituents of the n-hexane extract and thus seem to contribute to the plant's in vitro activity.

Inhibitory effects of maesanin and analogs on arachidonic acid metabolizing enzymes

The substituted 1,4-benzoquinone, maesanin (1), is a potent 5-lipoxygenase (5-LO) inhibitor present in the fruit of Maesa lanceolata Forssk. Thirteen natural, synthetic, semisynthetic, and microbially transformed analogs of 1 were tested for their in vitro inhibition of 5-lipoxygenase (5-LO) and cyclooxygenase-1 (COX-1). Maesanin was the most active 5-LO inhibitor. All other analogs were inactive or less active than the natural products as 5-LO inhibitors. None of the tested compounds was strongly active in the COX-1 inhibition assay.

[The combined effect of psychotherapy and fluoxetine on obesity]

Obesity as psychosomatic disease is a mass phenomenon. The number of obese males (BMI > 30) became doubled in the last ten years. In the etiology of obesity play an important role the reactive obesity. In the background of "yo-yo syndrome" often could be found depression, or other psychotic disorder. The low self-esteem, body dissatisfaction, tension, anxiety disorders is well-known in a slimming diet. Obese subjects (n = 29) who were admitted on their request with a view to losing weight were examined (Hamilton Depressive Scala, Hamilton Anxietas Scala, Eating Attitude Test) Physical Conditioning and internal Medicine Department of National Sports Medicine Institute, Budapest. Among obesities with mild and severe depression as treatment of somatic complications was used fluoxetine, in severe cases and depression with severe anxiety was associated with supportive or cognitive-behavioral treatment. The prevalence of binge eating disorders were at 57% and bulimia nervosa was at 3% in using population (n = 29). Decreasing of anxiety and grade of depression significantly correlated with body mass index (p < 0.023, F = 1.997, p < 0.034, F = 3.131). The treatment of fluoxetine significantly correlated with body mass index (T1: p < 0.023, T2: p < 0.03, T3: p < 0.004). The patients indicated their well being as fluoxetine reduced eating, satiety and lower binges.

Eating disorders and depression in Hungarian women with menstrual disorders and infertility

Menstrual disorders are among the most frequent somatic complications and symptoms of eating disorders. This study was designed to assess the prevalence of eating disorders connected to menstrual disorders of a non-organic origin in women at two gynecological out-patient departments. We performed a survey via questionnaires (ANIS: Anorexia Nervosa Inventory Scale; BCDS: Bulimic Cognitive Distortions Scale; BITE: Bulimia Investigation Test, Edinburgh; EDI: Eating Disorders Inventory; BDI: Beck Depression Inventory). Among 75 women tested we found a prevalence figure of 4% for anorexia nervosa (AN) and 12% for bulimia nervosa (BN). The total prevalence of clinical and subclinical eating disorders syndromes was 44%. The prevalence of depression was 64% for all respondents, whilst severe depression accounted for 11%. This study demonstrates the (relatively) higher frequency of bulimia nervosa in Hungary, compared with other countries.

5-Methylflavasperone and rhamnetin from Guiera senegalensis and their antioxidative and 5-lipoxygenase inhibitory activity

From the methylene chloride extract of the leaves of Guiera senegalensis a novel naphthopyran, 5-methylflavasperone (5,8,10-trimethoxy-2-methyl-4 H-naphtho[1,2-b]pyran-4-one), as well as rhamnetin were isolated. Rhamnetin showed a strong inhibitory activity on 5-lipoxygenase from porcine leucocytes with an IC50 value of 0.7 microM whereas 5-methylflavasperone revealed only a weak inhibitory activity (IC50 > 200 microM). In the deoxyribose assay both compounds exerted similar antiradicalar effects (IC50 15.8 and 16.7 microM, respectively). In another assay only rhamnetin inhibited peroxidation of phospholipid liposomes (IC50 = 2.4 microM). For 5-methylflavasperone no dose dependent inhibition could be observed.

Antimicrobial activity of Pelargonium essential oils added to a quiche filling as a model food system

Eight essential oils obtained by steam distillation from the scented leaves of Pelargonium species and cultivars were added at 250, 500 and 1000 ppm to a quiche filling, inoculated with either Saccharomyces ludwigii or Zygosaccharomyces bailii (at 10(8) cfu g-1), Salmonella enteriditis or Listeria innocua (at 10(9) cfu g-1). The quiche fillings were then kept at 25 degrees C for 24 h and the residual number of micro-organisms determined using the pour plate technique. There was an effective antimicrobial activity by the Pelargonium essential oils at 250 ppm, comparable with that of commercial thyme oil, an excellent antimicrobial agent, against Saccharomyces ludwigii and Zygosaccharomyces bailii, and a lesser inhibition compared with commercial thyme against Salm, enteriditis. There was a greater diversity of activity against L. innocua, which was in some cases more effective than commercial thyme oil. At 500 ppm, there was a greatly increased inhibition of microbial growth using the Pelargonium essential oils, which was comparable with that of commercial thyme, clove, geranium and coriander oils. As there is no evidence for the toxicity of any of these novel Pelargonium oils, and their odour does not make the delicately flavoured quiche filling unpalatable, there is a strong potential for their use in food processing.

5-Lipoxygenase and cyclooxygenase-1 inhibitory active compounds from Atractylodes lancea

Lipophilic extracts of Atractylodes lancea rhizomes exhibited potent inhibitory activities in 5-lipoxygenase [IC50 (5-LOX) = 2.9 micrograms/mL (n-hexane extract)] and cyclooxygenase-1 [IC50 (COX-1) = 30.5 micrograms/mL (n-hexane extract)] enzymatic assays. Bioactivity-guided fractionation of the n-hexane extract led to the isolation of a new compound atractylochromene (1), a potent inhibitor in both test systems [IC50 (5-LOX) = 0.6 microM, IC50 (COX-1) = 3.3 microM]. Also obtained was 2-[(2E)-3,7-dimethyl-2,6-octadienyl]-6-methyl-2,5-cyclohexadiene-1 ,4-dione (2), which showed a selective inhibitory activity against 5-LOX [IC50 (5-LOX) 0.2 microM, IC50 (COX-1) 64.3 microM]. The sesquiterpene atractylon (3) and the coumarin osthol (4) turned out to be moderate but selective 5-lipoxygenase inhibitors. Atractylenolides I (5), II (6), and III (7) showed no significant inhibitory effects for either enzyme. Structures were established by spectral data interpretation.

[Prevalence of menstrual and eating disorders among infertile women]

Menstrual disorders are among the most frequent somatic complications and symptoms of eating disorders. Since 1972 amenorrhea has been registered among the diagnostic criteria of anorexia nervosa (AN). Although such a criterion is not essential for establishing a case of bulimia nervosa (BN), international research has, on several occasions, described menstruational disorders (in 95% of the cases) and amenorrhea (in 20% of the cases). This study was designed to assess the prevalence of eating disorders connected to menstruational disturbances having no organic causes. Our method was the following: the test was carried out via questionnaires (ANIS, BCDS, BITE, EDI, BDI) completed by patients of endocrine surgery of two gynecological out-patient wards. We have found the following (n = 75) prevalence figures: AN: 4%, BN: 12% while the total prevalence of clinical and subclinical eating disorder syndromes was at 44%. Our findings, are in line with other international findings.

[The female athletes' triad: eating disorders, amenorrhea, osteoporosis]

The study provides a summary of the most important features of eating disorders, amenorrhoea and osteoporosis jointly called the female athletes' triad. Considering the seriousness of the various symptoms, different branches of sport are affected to a different degree, which could be explained by the predispositioning risk factors being featured differently. The weight of the problem is indicated by the fact that eating disorders in female athletes show a 15-62%, while amenorrhea a 3.4-66% prevalence. There is no similar comprehensive figure concerning osteoporosis. Though various studies make the connection unambiguous, there can be no doubt about the urgency of further tests with respect to screening, therapy and prevention, as well.

Crystallization of bovine adrenodoxin reductase in a new unit cell and its crystallographic characterization

Plate-like crystals of adrenodoxin reductase from bovine adrenocortical mitochondria were obtained in a new modification. The crystals belong to the monoclinic space group C2 with cell parameters a = 85.94 A, b = 62.64 A, c = 128.55 A and beta = 99.8 degrees. There are two molecules in the asymmetric unit. The crystals diffract to better than 3.0 A resolution at 4 degrees C.

Diagnostic problems in nodular regenerative hyperplasia (nodular transformation) of the liver. Review of the literature and report of two cases

Nodular regenerative hyperplasia (NRH) is a rare lesion of the liver associated with portal hypertension in more than half of patients. We present two cases demonstrating complications and diagnostic problems of NRH and review the pathogenesis, clinical, radiologic, and pathologic features of 240 cases in the literature. Patient 1 died from variceal bleeding as a complication of NRH. Patient 2 presented with ascites. Sonographic, computed-tomographic and magnetic resonance findings did not differ from liver cirrhosis. Three needle biopsies showed nonspecific reactive hepatitis. Wedge liver biopsy provided the correct diagnosis of NRH and a shunt operation was performed. Non-Hodgkin's lymphoma (centroblastic type) was diagnosed three years after NRH. At present there is no clinical or radiologic evidence of progression of NRH in this patient. The diagnosis of NRH cannot be made without histologic examination. Correct diagnosis is difficult in percutaneous needle biopsy. Therefore, laparoscopically guided liver biopsy or wedge biopsy is often necessary for diagnosis. NRH should be included in the differential diagnosis of portal hypertension. Portal diversion can be considered.

Pulsatile non-Newtonian blood flow in three-dimensional carotid bifurcation models: a numerical study of flow phenomena under different bifurcation angles

Flow and stress patterns in human carotid artery bifurcation models, which differ in the bifurcation angle, are analysed numerically under physiologically relevant flow conditions. The governing Navier-Stokes equations describing pulsatile, three-dimensional flow of an incompressible non-Newtonian fluid are approximated using a pressure correction finite element method, which has been developed recently. The non-Newtonian behaviour of blood is modelled using Casson's relation, based on measured dynamic viscosity. The study concentrates on flow and stress characteristics in the carotid sinus. The results show that the complex flow in the sinus is affected by the angle variation. The magnitude of reversed flow, the extension of the recirculation zone in the outer sinus region and the duration of flow separation during the pulse cycle as well as the resulting wall shear stress are clearly different in the small angle and in the large angle bifurcation. The haemodynamic phenomena, which are important in atherogenesis, are more pronounced in the large angle bifurcation.

Pulsatile non-Newtonian flow characteristics in a three-dimensional human carotid bifurcation model

Numerical analysis of flow phenomena and wall shear stresses in the human carotid artery bifurcation has been carried out using a three-dimensional geometrical model. The primary aim of this study is the detailed discussion of non-Newtonian flow velocity and wall shear stress during the pulse cycle. A comparison of non-Newtonian and Newtonian results is also presented. The applied non-Newtonian behavior of blood is based on measured dynamic viscosity. In the foreground of discussion are the flow characteristics in the carotid sinus. The investigation shows complex flow patterns especially in the carotid sinus where flow separation occurs at the outer wall throughout the systolic deceleration phase. The changing sign of the velocity near the outer sinus wall results in oscillating shear stress during the pulse cycle. At the outer wall of the sinus at maximum diameter level the shear stress ranges from -1.92 N/m2 to 1.22 N/m2 with a time-averaged value of 0.04 N/m2. At the inner wall of the sinus at maximum diameter level the shear stress range is from 1.16 N/m2 to 4.18 N/m2 with a mean of 1.97 N/m2. The comparison of non-Newtonian and Newtonian results indicates unchanged flow phenomena and rather minor differences in the basic flow characteristics.

Three-dimensional numerical analysis of pulsatile flow and wall shear stress in the carotid artery bifurcation

To analyse the pulsatile flow field and the mechanical stresses in a three-dimensional carotid artery bifurcation model, computer simulation is applied. The approximation of the Navier-Stokes equations uses a pressure correction finite element method. Numerical results are presented for axial and secondary flow velocity and wall shear stresses with special emphasis on the fluid dynamics in the carotid sinus. This region is of major interest because it is affected preferentially by lesions. Detailed local flow studies as carried out here should lead to a further insight into the mechanisms of atherogenesis. The flow conditions used in the study were chosen according to Ku et al. (Arteriosclerosis 5, 293-302, 1985). The results of this numerical analysis agree in the essential features with their experimental results.

Numerical flow studies in human carotid artery bifurcations: basic discussion of the geometric factor in atherogenesis

In this study fluid dynamic variables are analysed numerically in different human carotid artery bifurcation models in order to clarify the geometric factor in carotid bifurcation atherogenesis. The geometric variations describe healthy human carotid bifurcation anatomy and concern the shape of the carotid sinus and the angle between the branches. The flow conditions remain unchanged. The governing Navier--Stokes equations describing incompressible, pulsatile, three-dimensional viscous flow are approximated using a pressure correction finite element procedure which has been developed for time-consuming, three-dimensional, time-dependent viscous flow problems. The study concentrates on flow velocity, on detailed analysis of flow separation and flow recirculation, and on wall shear stress distribution. The results show that the extension and the location of the recirculation zone in the sinus as well as the duration of separated flow during the pulse cycle are affected by the geometrical variations. In view of the significance of the reversed flow zones and of the accompanied low shear regions in atherogenesis the geometry-dependent flow separation characteristics in the sinus is of substantial interest.

Pulsatile non-Newtonian blood flow simulation through a bifurcation with an aneurysm

Blood flow is analysed by means of computer simulation in an idealized arterial bifurcation model which is pathologically altered by a saccular aneurysm. The theoretical study of the flow pattern and the paths of fluid particles is carried out under pulsatile Newtonian and non-Newtonian flow conditions. The governing equations are solved numerically with the use of the finite element method. The results show the disturbed blood flow in the bifurcation and the relatively low intra-aneurysmal flow circulation. In addition to the study of basic flow patterns in the segment, a comparison of non-Newtonian and Newtonian results is carried out. This comparison proves that for the considered large artery model under physiological flow conditions where the yield number is relatively low there is no essential difference in the results.

[Problems of the stone-free gallbladder, a report on 276 cholecystectomies]

Different kinds of disease of the gallbladder without stones are demonstrated. The indication for cholecystectomy is given by anamnesis, radiological findings and the exact exploration of the adjoining organs. There is made a difference between absolute and relative indications. Among 6,311 cholecystectomies there are 276 gallbladders without stones (4.37%). The results of postoperative controls are reported, more than 76% of the patients are absolutely free, 16% are relatively free of complaints.

[Endoscopic manometry in the common bile duct]

Reproducible results were obtained by endoscopic transpapillary pressure measurements with the help of a constantly perfused catheter. Manometric measurements were performed in 51 patients without any premedication. 14 patients with a normal biliary system were compared with 17 patients after cholecystectomy, 14 patients with stones in the common bile duct and 6 patients after papillotomy. Although there were significant differences in the diameter of the common bile duct in the four groups, only the papillotomized patients demonstrated a distinct change of the pressure in the bile duct. In these patients almost no pressure gradient existed between the biliary ducts and the duodenum. On the other hand, there was an increase in intraluminal pressure in the 2 patients with papillary stenosis. Endoscopic manometric measurements in the common bile duct are indicated to obtain reliable data on stenosis of the papilla duodeni, insufficient papillotomy or recurrent stenosis.