Neural responses of OCD patients towards disorder-relevant, generally disgust-inducing and fear-inducing pictures

This functional magnetic resonance imaging study investigated the disgust- and fear-reactivity of patients suffering from obsessive-compulsive disorder (OCD). Ten OCD patients were scanned while viewing blocks of pictures showing OCD triggers from their personal environment and OCD-irrelevant disgust-inducing, fear-inducing and neutral scenes. Afterwards, the patients rated the intensity of the induced disgust, fear and OCD symptoms. The responses were compared with those of 10 healthy control subjects. The disorder-relevant pictures provoked intense OCD symptoms in the clinical group associated with increased activation in the bilateral prefrontal cortex, the left insula, the right supramarginal gyrus, the left caudate nucleus and the right thalamus. The patients gave higher disgust and fear ratings than the controls for all aversive picture categories. Neural responses towards the disorder-irrelevant disgusting and fear-inducing material included more pronounced insula activation in patients than controls. Summarizing, photos of individual OCD-triggers are an effective means of symptom provocation and activation of the fronto-striato-thalamo-parietal network. The increased insular reactivity of OCD patients during all aversive picture conditions might mirror their susceptibility to experience negative somatic states.

Gender differences in the processing of disgust- and fear-inducing pictures: an fMRI study

We examined whether males and females differ in the intensity and laterality of their hemodynamic responses towards visual disgust and fear stimuli. Forty-one female, and 51 male subjects viewed disgust-inducing, fear-inducing and neutral pictures in an fMRI block design. Self-report data indicated that the target emotions had been elicited successfully with women responding stronger than men. While viewing the fear pictures, which depicted attacks by humans or animals, men exhibited greater activation in the bilateral amygdala and the left fusiform gyrus than women. This response pattern may reflect greater attention from males to cues of aggression in their environment. Further, the lateralization of brain activation was comparable in the two genders during both aversive picture conditions.

Single-spin asymmetries in semi-inclusive deep-inelastic scattering on a transversely polarized hydrogen target

Single-spin asymmetries for semi-inclusive electroproduction of charged pions in deep-inelastic scattering of positrons are measured for the first time with transverse target polarization. The asymmetry depends on the azimuthal angles of both the pion (phi) and the target spin axis (phi(S)) about the virtual-photon direction and relative to the lepton scattering plane. The extracted Fourier component sin((phi+phi(S))(pi)(UT) is a signal of the previously unmeasured quark transversity distribution, in conjunction with the Collins fragmentation function, also unknown. The component sin((phi-phi(S)(pi)(UT) arises from a correlation between the transverse polarization of the target nucleon and the intrinsic transverse momentum of quarks, as represented by the previously unmeasured Sivers distribution function. Evidence for both signals is observed, but the Sivers asymmetry may be affected by exclusive vector meson production.

Prophylactic SSRI during interferon alpha re-therapy in patients with chronic hepatitis C and a history of interferon-induced depression

Only limited data are available on selective serotonin re-uptake inhibitor (SSRI) prophylaxis for antiviral re-treatment in hepatitis C patients with previous interferon-induced major depressive episodes. Therefore, we investigated the efficacy and safety of secondary SSRI prophylaxis in these patients. In a prospective and longitudinal study, repeated psychometric testing (Hospital Anxiety and Depression Scale) was performed before, during, and after antiviral re-treatment. Chronic hepatitis C virus (HCV)-infected patients, who had been psychometrically monitored during an unsuccessful previous antiviral therapy, and had developed major depression were included. Interferon re-therapy with SSRI prophylaxis was started (n = 8). The reference group was comprised of HCV patients without a history of interferon-associated depression and also a group who were previously unsuccessfully treated with interferon and were re-treated without SSRI prophylaxis (n = 9). All patients receiving SSRI prophylaxis were able to complete interferon re-therapy as scheduled. As in the first therapeutic course, depression scores were significantly elevated during re-treatment also (P < 0.001). Depression scores were significantly lower (P =0.036) during interferon re-therapy with SSRI prophylaxis. Reference group subjects showed similar depression scores during first therapy and re-therapy (P > 0.05). In conclusion, hepatitis C patients with a history of interferon-induced major depression can be successfully re-treated with peginterferon/ribavirin and concomitant SSRI prophylaxis. In these patients, SSRI prophylaxis is safe and efficacious and should be considered, if antiviral re-therapy is indicated.

Heart failure, platelet activation and inhibition of the renin-angiotensin-aldosterone system

Heart failure is a highly prevalent disease in aging western populations, associated with a substantially increased risk of thromboembolic events, not only in severe but even in mild to moderate stages. This can partly be attributed to concomitant atrial fibrillation, a well-known risk factor for stroke, as well as a "hypercoagulable state" including formation of intraventricular thrombi. Left ventricular dysfunction results in decreased cardiac output, pulmonary congestion and neurohumoral activation with marked stimulation of the renin-angiotensin-aldosterone system. Besides its contribution to progressive left ventricular remodelling, activation of the renin-angiotensin-aldosterone system is enhanced in the development of vascular endothelial dysfunction in heart failure, resulting in decreased nitric oxide bioavailability. Nitric oxide, however, controls vascular tone and inhibits platelet activation. Enhanced platelet activation has recently been described in patients with heart failure in sinus rhythm. This article summarises the potential contribution to platelet activation of vascular endothelial dysfunction and reduced formation of the platelet inhibitor nitric oxide, which increase further the risk for thromboembolic events in heart failure. Beneficial modulation of cardiac remodelling, left ventricular function, neurohumoral activation, endothelial dysfunction and platelet activation can be achieved by inhibition of the renin-angiotensin-aldosterone system.

Hemodynamic effects of negative emotional pictures - a test-retest analysis

We investigated subjective and hemodynamic responses towards disgust-inducing, fear-inducing, and neutral pictures in a functional magnetic resonance imaging study. Within an interval of 1 week, 24 male subjects underwent the same block design twice in order to analyze possible response changes to the repeated picture presentation. The results showed that disgust-inducing and fear-inducing scenes provoked a similar activation pattern in comparison to neutral scenes. This included the thalamus, primary and secondary visual fields, the amygdala, the hippocampus, and various regions of the prefrontal cortex. During the retest, the affective ratings hardly changed. In contrast, most of the previously observed brain activations disappeared, with the exception of the temporo-occipital activation. An additional analysis, which compared the emotion-related activation patterns during the two presentations, showed that the responses to the fear-inducing pictures were more stable than the responses to the disgust-inducing ones.

[Requirements and recommendations for performing endosonographies]

For improvement of quality the working group of the Society of Gastroenterology in Nordrhein-Westfalen (Germany) was engaged with the questions, which apparative, personal and training conditions for endoscopic ultrasound are useful. The following proposals were preliminarily presented at the annual Congress of the DGVS (German Society of Digestive and Metabolic Diseases) 2001. They are thought to be subject of discussion for guidelines to be elaborated by this national society.

Generalized parton distributions from lattice QCD

We perform a quenched lattice calculation of the first moment of twist-two generalized parton distribution functions of the proton, and assess the total quark (spin and orbital angular momentum) contribution to the spin of the proton.

Flavor decomposition of the sea-quark helicity distributions in the nucleon from semiinclusive deep inelastic scattering

Double-spin asymmetries of semiinclusive cross sections for the production of identified pions and kaons have been measured in deep inelastic scattering of polarized positrons on a polarized deuterium target. Five helicity distributions including those for three sea quark flavors were extracted from these data together with reanalyzed previous data for identified pions from a hydrogen target. These distributions are consistent with zero for all three sea flavors. A recently predicted flavor asymmetry in the polarization of the light quark sea appears to be disfavored by the data.

[Risk factors of premature birth and their significance for prevention and health promotion--an analysis based on the BabyCare Program]

In this report: Preterm birth will be characterized as a so far widely neglected public health problem in Germany. Actual evidence with respect to epidemiological and intervention knowledge will be summarized. Objectives, methods and routines of the BabyCare program will be presented. Associations between main risk factors and preterm birth will be calculated. Considerable deficiencies in nutritional habits and in micro nutritional intake will be summarized. And conclusions will be derived for future additional focussed actions in the prevention of preterm birth and other important complications in pregnancy within the program and for additional interventions in health policy which are imperative. It will be shown that the rate of preterm birth can be reduced and there is a high probability for further reduction by additional and targeted interventions in smoking, stress and especially nutrition.

Ekelempfindlichkeit: ein Vulnerabilitätsfaktor für essgestörtes Verhalten

Zusammenfassung. Theoretischer Hintergrund: Eine erhöhte Ekelempfindlichkeit wird als Vulnerabilitätsfaktor für Essstörungen diskutiert. Fragestellung: Gibt es einen Zusammenhang zwischen habituellen und aktuellen Ekelreaktionen von Frauen und deren Neigung zu essgestörtem Verhalten? Methode: Ausprägungen von 85 Frauen in einem Essstörungs-Inventar (ESI, Diehl & Staufenbiel, 1994 ) und einem Fragebogen zur Erfassung der Ekelempfindlichkeit (FEE, Schienle et al., 2002 ) wurden korreliert. Außerdem wurden die emotionalen Einstufungen für Bilder der Kategorien “Ekel“, “Angst“ und “Neutral“ mit den ESI-Werten korreliert. Ergebnisse: Die Korrelation zwischen ESI und FEE betrug r = .41; positive Zusammenhänge ergaben sich auch zwischen ESI-Werten und Ekeleinstufungen der Ekel- (r = .34), Angst- (r = .33) und Neutralbilder (r = .41). Schlussfolgerung: Dieses Ergebnis weist auf die mögliche Rolle einer verstärkten Ekelneigung für die Entstehung und Aufrechterhaltung von Essstörungen hin.

Geometric scaling in inclusive eA reactions and nonlinear perturbative QCD

We report on geometric scaling in inclusive eA scattering data from the NMC and E665 experiments. This scaling and nuclear shadowing follows the pattern expected from nonlinear perturbative QCD for zero impact parameter at sufficiently small x(bj) and is compatible with geometric scaling in ep.

[Sentinel lymph node excision (SLNE) and positron emission tomography in the staging of stage I-II melanoma patients]

BACKGROUND AND OBJECTIVE

Sentinel lymph node excision (SLNE) and positron emission tomography (PET) were evaluated in the staging of 51 Stage I and II melanoma patients (staged according to the guidelines of the German Dermatological Society).

PATIENTS/METHODS AND RESULTS

Tumor thickness ranged from 1.0 mm to 6.0 mm (median: 1.5 mm; mean: 2.07 mm). At least one sentinel lymph node (SLN) was excised in all patients; 80 SLN were excised from 69 lymphatic drainage areas. Positive SLN were detected in 6 patients (11.8%). Additional positive lymph nodes were not detected in any of these patients in the following complete lymph node dissection of the affected lymph node basin. Preoperative PET was performed in 40 patients and did not detect any of the micrometastases that were subsequently found by SLNE. During the follow up of 7-40 months (mean 21.9 months) 3 patients experienced tumor progression; 2 of 3 had a positive SLN.

CONCLUSIONS

According to the current literature SLNE is recommended in primary tumors greater than 1 mm thickness. PET cannot be expected to give additional information in the staging of stage I-II patients.

Evidence for quark-hadron duality in the proton spin asymmetry A1

Spin-dependent lepton-nucleon scattering data have been used to investigate the validity of the concept of quark-hadron duality for the spin asymmetry A1. Longitudinally polarized positrons were scattered off a longitudinally polarized hydrogen target for values of Q2 between 1.2 and 12 GeV2 and values of W2 between 1 and 4 GeV2. The average double-spin asymmetry in the nucleon resonance region is found to agree with that measured in deep-inelastic scattering at the same values of the Bjorken scaling variable x. This finding implies that the description of A1 in terms of quark degrees of freedom is valid also in the nucleon resonance region for values of Q2 above 1.6 GeV2.

Exclusive annihilation pp-->gammagamma in a generalized Parton picture

Exclusive proton-antiproton annihilation into two photons at large s ( approximately 10 GeV2) and /t/,/u/ approximately s can be described by a generalized parton picture analogous to the "soft mechanism" in wide-angle real Compton scattering. The two photons are emitted in the annihilation of a single fast quark and antiquark. The matrix element describing the transition of the pp system to a qq pair can be related to the timelike proton elastic form factors as well as to the quark/antiquark distributions measured in inclusive deep-inelastic scattering. The reaction could be studied with the proposed 1.5-15 GeV high-luminosity antiproton storage ring (HESR) at GSI.

Q2 dependence of nuclear transparency for exclusive rho0 production

Exclusive coherent and incoherent electroproduction of the rho(0) meson from 1H and 14N targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to the lifetime of hadronic fluctuations of the virtual photon, and squared four-momentum of the virtual photon (-Q2). The ratio of 14N to 1H cross sections per nucleon, called nuclear transparency, was found to increase (decrease) with increasing l(c) for coherent (incoherent) rho(0) electroproduction. For fixed l(c), a rise of nuclear transparency with Q2 is observed for both coherent and incoherent rho(0) production, which is in agreement with theoretical calculations of color transparency.

Disgust Processing in Phobia of Blood-Injection-Injury

Abstract An elevated disgust sensitivity (DS) is considered to be a vulnerability factor for the development of a blood-injection-injury (BII) phobia. Within the present functional Magnetic Resonance Imaging (fMRI) study, 12 female BII phobics were scanned while viewing alternating blocks of 40 disgust-inducing, 40 fear-inducing, and 40 affectively neutral pictures. Each block lasted 60s and was repeated six times during the experiment. All scenes were phobia-irrelevant. Afterwards, the subjects gave affective ratings for the pictures and described their DS on a self-report measure for different areas (e.g., poor hygiene, unusual food, death/deformation). The responses were compared with those of 12 nonphobic females. The BII phobics showed a stronger occipital activation within the right cuneus and lingual gyrus during the first viewing of the disgusting pictures. Aside from this finding, which could be interpreted as reflecting increased attention, there was little evidence for a generally elevated DS in BII phobia. On the DS questionnaire, the patients had indicated a greater reactivity only for disorder-relevant contents (death/deformation). Further, both groups gave similar disgust ratings for the pictures and showed comparable brain-dynamic responses over all blocks of the disgust condition, which included the activation of both amygdalae and the left inferior frontal gyrus.

Exclusive photoproduction of hard dijets and magnetic susceptibility of the QCD vacuum

We argue that coherent production of hard dijets by linearly polarized real photons can provide direct evidence for chirality violation in hard processes, the first measurement of the magnetic susceptibility of the quark condensate and the photon distribution amplitude. It can also serve as a sensitive probe of the generalized gluon parton distribution. Numerical calculations are presented for HERA kinematics.

High-altitude pulmonary edema: potential protection by red wine

High-altitude pulmonary edema (HAPE) is the predominant cause of death due to high-altitude illness. At first sight, the observation that mountaineers regularly consume red wine in order to "feel better" seems to be paradoxical because, especially at higher altitudes, alcohol consumption could be detrimental. In this article, we review the potential mechanisms by which the components of red wine may beneficially affect the development of HAPE.

DATA SYNTHESIS

The underlying cause of HAPE is the altitude-related reduction in barometric pressure, which leads to a decrease in partial pressure of oxygen in the alveolae and subsequently in the pulmonary capillaries and arterial system. Two cellular mechanisms have been described, both of which increase pulmonary vascular tone: enhanced endothelin 1 production and the increased generation of reactive oxygen species. Recent evidence has indicated that some of the compounds of red wine suppress endothelin 1 gene expression, and the anti-oxidative properties of red wine have been previously reported.

CONCLUSION

This article briefly summarises the pathophysiological cellular events leading to HAPE and describes the potential mechanisms by which the ingredients of red wine may have a beneficial effect.

Cronin effect in hadron production off nuclei

Recent data from RHIC for high- pT hadrons raised again the long-standing problem of quantitatively understanding the Cronin effect, i.e., nuclear enhancement of high- pT hadrons. All existing models for the Cronin effect rely on a fit to the data to be explained. We develop a phenomenological description based on the light-cone QCD-dipole approach which allows one to explain data without fitting to them and to provide predictions for pA collisions at RHIC and LHC. We point out that the underlying mechanism drastically changes with energy, from incoherent production of high- pT hadrons on different nucleons at low energies, to an entirely coherent process at very high energies.

Paroxetine for the treatment of interferon-alpha-induced depression in chronic hepatitis C

BACKGROUND

Psychiatric side-effects may require dose reduction or premature discontinuation of interferon therapy in chronic hepatitis C. New strategies are needed in order to prevent the premature termination of interferon therapy.

AIM

To evaluate prospectively the efficacy and tolerability of antidepressant therapy (paroxetine, a selective serotonin reuptake inhibitor) in patients with chronic hepatitis C treated with interferon-alpha who have developed interferon-induced major depression.

METHODS

A sub-group of 14 individuals from 121 consecutively treated hepatitis C patients developed substance-induced major depression without suicidal ideation during interferon-alpha treatment. The individuals in this sub-group received paroxetine after the occurrence of depression (20 mg daily until termination of interferon therapy). Diagnostic scores for depression (and anger-hostility) were obtained in a repeated measures design (Hospital Anxiety and Depression Scale and Symptom Checklist 90 Items Revised).

RESULTS

Eleven of the 14 patients (78.6%) with interferon-induced major depression were able to complete interferon-alpha therapy as scheduled under concomitant paroxetine treatment (three dropouts: insufficient improvement of depression, occurrence of epileptic seizures, paroxetine-induced nausea/dizziness). Within 4 weeks after the start of paroxetine medication, depression scores declined significantly in all patients.

CONCLUSIONS

Our data suggest that concomitant therapy with paroxetine is an effective way to treat interferon-induced depression in patients with chronic hepatitis C.

Messenger ribonucleic acid levels of interleukin-1 beta, interleukin-6 and interleukin-8 in the lower uterine segment increased significantly at final cervical dilatation during term parturition, while those of tumor necrosis factor alpha remained unchanged

OBJECTIVE

To investigate the content of tumor necrosis factor alpha, interleukin-1 beta, interleukin-6 and interleukin-8 messenger ribonucleic acid (mRNA) in the lower uterine segment during term parturition.

STUDY DESIGN

mRNA extracts from the lower uterine segment obtained from 53 women undergoing non-elective caesarean section at term were analyzed by semi-quantitative reverse transcriptase polymerase chain reaction. The patients were grouped according to cervical dilatation (less than 2 cm, n=18; 2 to less than 4 cm, n=13; 4-6 cm, n=7; more than 6 cm, n=15) at the time of caesarean section.

RESULTS

Interleukin-1 beta and interleukin-8 mRNA-contents at more than 6 cm cervical dilation were significantly higher than at less than 2 cm. The levels of interleukin-6 were already significantly increased in the 4-6 cm group, while the tumor necrosis factor alpha ribonucleic acid content did not change during parturition.

CONCLUSION

The process of cervical dilatation during parturition at term is associated with an increased expression of interleukin-1 beta, interleukin-6 and interleukin-8 mRNA in the lower uterine segment. These findings support the theory that the activation of the inflammatory network plays an important role in the progress of cervical dilatation.

mARVCF cellular localisation and binding to cadherins is influenced by the cellular context but not by alternative splicing

ARVCF, a member of the catenin family, is thought to contribute to the morphoregulatory function of the cadherin-catenin complex. Recently, we reported the isolation and characterisation of murine ARVCF (mARVCF), particularly its interaction with M-cadherin. Here, we describe the identification of novel mARVCF isoforms that arise by alternative splicing. At the N-terminus, alternative splicing results in the inclusion or omission of a coiled-coil region probably important for protein-protein interactions. At the C-terminus, four isoforms also differ by domains potentially important for selective protein-protein interaction. The eight putative mARVCF isoforms were expressed as EGFP-fusion proteins in six different cell lines that exhibit a distinct pattern of cadherins. Apparently, binding of the mARVCF isoforms to M-, N-, or E-cadherin is generally unaffected by their altered N- and C-termini, as revealed by the MOM recruitment assay. However, mARVCF isoforms reproducibly exhibit differential localisation in distinct cellular environments. For example, mARVCF isoforms are unable to colocalise with N-cadherin in EJ28 carcinoma cells but do so in HeLa cells. Our results suggest that the subcellular localisation of mARVCF may be determined not only by the presence or absence of an appropriate interaction partner, in this case cadherins, but also by the cellular context.

Formation of glucoside conjugates during biotransformation of dibenzofuran by Penicillium canescens SBUG-M 1139

Penicillium canescens oxidises dibenzofuran (DBF) to produce monohydroxylated derivatives and other more hydrophilic metabolites. These substances are water-soluble but unstable in organic solvents such as ethyl acetate, acetone or dichloromethane. Both extraction with ethyl acetate and enzymatic treatment of the aqueous culture filtrate with beta-glucuronidase led to decay of the hydrophilic metabolites and indicated these products to be glycoside conjugates. The glycosyl residue was identified as glucose both by liquid chromatography and by the use of glucose oxidase. The conjugate pattern formed was the same in type and amount, independent of the carbon source used for cultivation of the fungus. Clearly, DBF transformation in P canescens occurred in two phases: first the conversion to 2-, 3-, and 4-hydroxydibenzofuran (phase I), followed by the formation of the corresponding glucosyl conjugates (phase II). In contrast, 2,3-dihydroxydibenzofuran added to the cultures was transformed by ring cleavage producing a muconic acid-like dead-end product.

Compliance with therapy in patients with chronic hepatitis C: associations with psychiatric symptoms, interpersonal problems, and mode of acquisition

Tolerance of interferon-a therapy for hepatitis C is often poor and medication is expensive. Compliance with diagnostic procedures and, even more important, with medical treatment is obviously critical to minimize the rate of dropouts and to maximize cost efficiency. Moreover, a good concordance with scheduled follow-ups is important for early recognition and treatment of interferon-associated side effects. Therefore, we investigated psychiatric symptoms, interpersonal problems, different modes of acquisition, and sociodemographic factors in HCV-infected patients as possible predictor variables of good versus poor compliance. In a longitudinal study, 74 patients with chronic hepatitis C (CHC) who fulfilled the criteria for treatment with interferon (IFN)-alpha-2b with or without ribavirin were investigated prospectively to identify those at risk for poor compliance during IFN medication. To assess predictive factors, we used both IIP-C (Inventory of Interpersonal Problems) and SCL-90-R (Symptom Check List 90 Items Revised) as psychometric instruments. Sociodemographic and somatic variables as well as compliance during IFN therapy were also evaluated. Poor compliance before or during medication was demonstrated by 23% (N = 17) of HCV patients. Sociodemographic factors and mode of acquisition, particularly former intravenous drug (IVD) abuse were not significantly linked with compliance. Logistic regression analysis demonstrated that the subgroup of patients with compliance problems was best identified by both pretherapeutic psychiatric symptoms and interpersonal problems. Predictive value was best and significant for anger-hostility (P = 0.009), intrusive (P = 0.014), depression (P = 0.015), and phobic anxiety (P = 0.049). Adopting this statistical prediction model, sensitivity was 47.1%, but specificity reached 98.3%. In total, 86.5% of cases were classified correctly. In situations of unclear indication for IFN therapy, psychological variables assessment of before the beginning of treatment may represent an additional decision-making factor.

Calorons and localization of quark eigenvectors in lattice QCD

We analyze the localization properties for eigenvectors of the Dirac operator in quenched lattice QCD in the vicinity of the deconfinement phase transition. Studying the characteristic differences between the Z3 sectors above the critical temperature T(c), we find indications for the presence of calorons.

Factors affecting mass transfer limited biodegradation in saturated porous media

Microbial degradation rates in the subsurface are not only limited by the physiological capacity of the organisms, but also by inefficient supply of nutrients to the microbes. Although mass transfer limitation of biodegradation in the subsurface has been postulated for years, experimental evidence is still scarce. In the column experiments described here, diffusive transport of 4-nitroanisole from the bulk solution to cells of Rhodococcus opacus strain AS2 immobilized on glass beads or sand appeared to be responsible for the slow transformation rates observed. Assuming steady state, we applied a coupled transformation/transport equation to these data (Best equation) and apparent bead-related mass transfer coefficients were found to increase in proportion to the surface area covered with bacteria. This implies that mass transfer coefficients for individual cells remained constant. In an idealized oligotrophic environment where cells are only loosely clustered and do not shield each other, we would therefore expect biodegradation rates to be independent from the longitudinal distribution of the total biomass along a given flow path. Moreover, apparent mass transfer coefficients increased with the grain size of the column fillings, but did not change upon varying the flow rate. With a limiting external transport step, overall transformation fluxes do not become saturated at concentrations as low as predicted for Michaelis-Menten-type kinetics. Mass transfer limitation thus offers a justification for the common assumption that biodegradation rates in the subsurface follow first order kinetics in a wide concentration range.

Auxin-induced elongation of short maize coleoptile segments is supported by 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one

Endogenous extractable factors associated with auxin action in plant tissues were investigated, especially their effects on elongation of 1-mm coleoptile segments of maize (Zea mays L.), in the presence of saturating 10 microM indole-3-acetic acid (IAA). The relative growth response, to auxin alone, was much smaller in segments shorter than 2-3 mm compared to 10-mm segments. Fusicoccin-induced elongation, however, was less affected by shortening the segments. A reduced auxin response may result from the depletion through cut surfaces of a substance required for IAA-mediated growth. Sucrose, phenolics like flavonoids, and vitamins were ruled out as the causal factors. A partially purified methanol extract of maize coleoptiles supported longterm, auxin-controlled elongation. The active material was also found among substances bleeding from scrubbed maize coleoptiles. The active factor from maize was further purified by HPLC and characterised by the UV spectrum and its pH shift. This factor was identified as 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) by mass spectroscopy. Activity tests confirmed that pure DIMBOA from other sources sustained auxin-induced elongation of short maize coleoptile segments. However, DIMBOA only partially restored the activity lost from short segments. This indicates that an additional factor, other than DIMBOA, is required. Extracts from Avena or Cucurbita did not contain the factor DIMBOA; it was active on maize elongation, but not on Avena coleoptiles or Cucurbita hypocotyls. This narrow specificity and the lack of DIMBOA action in short-term tests with maize indicate that DIMBOA is not the general auxin cofactor but may specifically "spare" the co-auxin in maize.

Towards a solution of the charmonium production controversy: k( perpendicular) factorization versus color-octet mechanism

The cross section of chi(cJ) hadroproduction is calculated in the k( perpendicular)-factorization approach. We find a significant contribution of the chi(c1) state due to non-applicability of the Landau-Yang theorem because of off-shell gluons. The results are in agreement with data and, in contrast to the collinear factorization, show a dominance of the color-singlet part and a strong suppression of the color octet contribution. Our results could therefore lead to a solution of the long-standing controversy between the color-singlet model and the color-octet mechanism.

Determination of the aerobic biodegradability of polymeric material in aquatic batch tests

Results of an international ring-test of two laboratory methods are presented for investigating the biodegradability of organic polymeric test materials in aquatic test systems based on respirometry and the evolution of carbon dioxide. These methods are developed further from the well-known standardized biodegradation tests ISO 9408 (1999) and ISO 9439 (1999), which have been successfully used for many years. The most important improvements are the extension of the test period up to six months, the increase of the buffer capacity and nutrient supply of the inorganic medium, an optimization of the inoculation, and optionally, the possibility of a carbon balance. A ring test, organized by the International Biodeterioration Research Group (IBRG), was run using a poly(,-caprolactone)-starch blend and an aliphatic-aromatic co-polyester as test materials and a microcrystalline cellulose powder as a reference material. The test results and the experience gained by the participants showed that the methods are suitable and practicable. The test methods have been meanwhile established as standards ISO 14851 (1999) and ISO 14852 (1999).

An effective and safe protocol involving zidovudine and caesarean section to reduce vertical transmission of HIV-1 infection

OBJECTIVE

To investigate zidovudine prophylaxis with caesarean section to reduce mother-to-infant HIV transmission.

INTERVENTIONS

Elective caesarean section before labour, usually at 36-38 weeks of gestation, plus a short oral course of zidovudine, normally starting at week 32, intravenous zidovudine before caesarean section and for 10 days for the neonate (the reduced Berlin regimen).

RESULTS

Of 179 mother-infant pairs 104 received no antiretroviral prophylaxis or therapy (control group), 48 received the reduced Berlin prophylaxis regimen, 18 received combination therapy and nine received only part of the prophylaxis regimen. Of the antiretroviral group, 68 were delivered by elective caesarean section. The HIV transmission rate was zero in the antiretroviral group [95% confidence interval (CI) 0-4.7] and 12.6% (6.4-19.0) in the control group. The reduction in vertical transmission was 90% for the Berlin regimen, with an 80 and 70% reduction in risk associated with antiretroviral treatment and caesarean section, respectively. Maternal CD4 cell count but not viral load had some confounding effect on the reduction in risk attributed to caesarean section and the prophylactic regimen. Neonatal haematological abnormalities associated with antiretroviral intervention lasted for up to 7 weeks. Weight and length, although significantly lower at birth, were normal by 6-8 weeks.

CONCLUSION

A much reduced three-arm regimen of zidovudine prophylaxis in combination with caesarean section before labour is highly effective in reducing the risk of vertical HIV transmission and is safe for the infant.

Emotional state, coping styles, and somatic variables in patients with chronic hepatitis C

The authors in a cross-sectional study examined 113 patients with chronic hepatitis C (CHC) without widely progressed or decompensated liver disease. The patients were investigated for emotional state (depression, anxiety, coping styles) and somatic/sociodemographic variables. A high percentage of patients had positive scores for depression (22.4%) and anxiety (15.2%). Mode of acquisition (e.g., former drug abuse) and histological grade of liver damage had no significant influence on emotional state or coping strategies. Older patients (> or = 50 years) were significantly more depressed (P = 0.024). Patients with a recently diagnosed CHC (> 4 weeks, < 6 months) had significantly lower scores for depression (P = 0.003) and anxiety (P = 0.001) than the subgroup with a time interval since initial diagnosis of more than 5 years. Recently diagnosed CHC patients also showed the highest levels of problem-solving behavior. Patients who were advised not to undergo an interferon therapy were significantly more depressed (P = 0.001) and anxious (P = 0.028). Older patients with CHC and patients with a long period since CHC diagnosis or who were advised not to undergo interferon therapy should be carefully and regularly assessed for depression, anxiety, and inappropriate coping styles.

Antigen presentation in extracellular matrix: interactions of T cells with dendritic cells are dynamic, short lived, and sequential

Cognate interactions of naive T cells with antigen-presenting dendritic cells require physical cell-cell contacts leading to signal induction and T cell activation. Using a three-dimensional collagen matrix videomicroscopy model for ovalbumin peptide-specific activation of murine and oxidative mitogenesis of human T cells, we show that T cells maintain vigorous migration upon cognate interactions to DC (dendritic cell), continuously crawl across the DC surface, and rapidly detach (median within 6-12 min). These dynamic and short-lived encounters favor sequential contacts with the same or other DC and trigger calcium influx, upregulation of activation markers, T blast formation, and proliferation. We conclude that a tissue environment supports the accumulation of sequential signals, implicating a numeric or "digital" control mechanism for an ongoing primary immune response.

Evidence for a single-spin azimuthal asymmetry in semi-inclusive pion electroproduction

Single-spin asymmetries for semi-inclusive pion production in deep-inelastic scattering have been measured for the first time. A significant target-spin asymmetry of the distribution in the azimuthal angle straight phi of the pion relative to the lepton scattering plane was formed for pi(+) electroproduction on a longitudinally polarized hydrogen target. The corresponding analyzing power in the sinstraight phi moment of the cross section is 0.022+/-0.005+/-0.003. This result can be interpreted as the effect of terms in the cross section involving chiral-odd spin distribution functions in combination with a chiral-odd fragmentation function that is sensitive to the transverse polarization of the fragmenting quark.

Synthesis of novel donor mimetics of UDP-Gal, UDP-GlcNAc, and UDP-GalNAc as potential transferase inhibitors

For the enzymatic transfer of galactose, N-acetylglucosamine, and N-acetylgalactosamine, UDP-Gal (1), UDP-GlcNAc (2), and UDP-GalNAc (3) are employed, and UDP serves as a feedback inhibitor. In this paper the synthesis of the novel UDP-sugar analogues 4, 5, and 6 as potential transferase inhibitors is described. Compounds 4-6 feature C-glycosidic hydroxymethylene linkages between the sugar and nucleoside moieties in contrast to the anomeric oxygens in the natural derivatives 1-3.

The disposition of 14C-labeled tacrolimus after intravenous and oral administration in healthy human subjects

Tacrolimus is a macrolide lactone with potent immunosuppressive properties. It has been shown in clinical studies to prevent allograft rejection. The pharmacokinetics of tacrolimus in healthy subjects and transplant patients has been described in earlier studies using immunoassay methods; however, detailed information on the absorption, distribution, metabolism, and excretion of tacrolimus using a radiolabeled drug is lacking. The objective of the present study was to characterize the disposition of tacrolimus after single i.v. (0.01 mg/kg) and oral (0.05 mg/kg) administration of 14C-labeled drug in six healthy subjects. Tacrolimus was absorbed rapidly after oral dosing with a mean Cmax and Tmax of 42 ng/ml and 1 h, respectively. The oral bioavailability was about 20%. After i.v. and oral dosing, most of the administered dose was recovered in feces, suggesting that bile is the principal route of elimination. Urinary excretion accounted for less than 3% of total administered dose. In systemic circulation, unchanged parent compound accounted for nearly all the radioactivity; however, less than 0.5% of unchanged drug was detectable in feces and urine. The excretion of the metabolites was formation-rate-limited. The mean total body clearance at 37.5 ml/min was equivalent to about 3% of the liver blood flow. Renal clearance was less than 1% of the total body clearance. The mean elimination half-life was 44 h.

[Psychoeducational-psychotherapeutic treatment of schizophrenic patients and their caregivers. II. Supplementary findings at a 2-year follow-up]

In this study we investigated whether, in conjunction with neuroleptics, a psychoeducational and cognitively oriented treatment for schizophrenic outpatients and their key-persons can improve the course of schizophrenic illness within a 2-year follow-up. This prospective randomized study covered a total of 191 schizophrenic patients (according to DSM-III-R) and comprised a psychoeducational training and cognitive psychotherapy for patients and counseling for their key persons in various combinations. Patients were examined before, immediately after and 2 years after the end of the intervention. Patients in the treatment groups reduced their overall psychopathology and their attention deficit. For patients receiving all three treatment conditions, there was a relevant preventive effect with regard to the rehospitalization rate appearing during the second year of the follow-up. We conclude that in the mid-term, a combination of psychoeducational and cognitively oriented therapy for patients and their keypersons can improve the course of schizophrenic illness.

Expression of pyruvate kinase M2 in preneoplastic hepatic foci of N-nitrosomorpholine-treated rats

The expression of the pyruvate kinase (PK) isoenzymes L and M2 was analysed in the livers of rats treated with the hepatocarcinogenic agent N-nitrosomorpholine (NNM) in the drinking water. In control animals L-PK expression was restricted to liver parenchymal cells, whereas M2-PK was detected in bile duct epithelial, blood vessel wall, endothelial and Kupffer cells. In rats treated with NNM proliferating oval cells were consistently L-PK negative and M2-PK positive, while the ductal cells of cholangiofibroses were clearly L-PK positive and coexpressed M2-PK. However, no morphological differentiation of ductal cells into hepatocyte-like cells was observed. In the clear and acidophilic cell foci storing glycogen in excess strong staining for L-PK was observed. In glycogen-poor foci induced by NNM a shift from L-PK to M2-PK expression takes place.