Light-induced reversible reorganizations in closed Type II reaction centre complexes: physiological roles and physical mechanisms.

The purpose of this review is to outline our understanding of the nature, mechanism and physiological significance of light-induced reversible reorganizations in closed Type II reaction centre (RC) complexes. In the so-called 'closed' state, purple bacterial RC (bRC) and photosystem II (PSII) RC complexes are incapable of generating additional stable charge separation. Yet, upon continued excitation they display well-discernible changes in their photophysical and photochemical parameters. Substantial stabilization of their charge-separated states has been thoroughly documented-uncovering light-induced reorganizations in closed RCs and revealing their physiological importance in gradually optimizing the operation of the photosynthetic machinery during the dark-to-light transition. A range of subtle light-induced conformational changes has indeed been detected experimentally in different laboratories using different bRC and PSII-containing preparations. In general, the presently available data strongly suggest similar structural dynamics of closed bRC and PSII RC complexes, and similar physical mechanisms, in which dielectric relaxation processes and structural memory effects of proteins are proposed to play important roles.

Gender may have an influence on the relationship between Functional Movement Screen scores and gait parameters in elite junior athletes - A pilot study.

Aims The aim of this study was to examine the effects of gender on the relationship between Functional Movement Screen (FMS) and treadmill-based gait parameters. Methods Twenty elite junior athletes (10 women and 10 men) performed the FMS tests and gait analysis at a fixed speed. Between-gender differences were calculated for the relationship between FMS test scores and gait parameters, such as foot rotation, step length, and length of gait line. Results Gender did not affect the relationship between FMS and treadmill-based gait parameters. The nature of correlations between FMS test scores and gait parameters was different in women and men. Furthermore, different FMS test scores predicted different gait parameters in female and male athletes. FMS asymmetry and movement asymmetries measured by treadmill-based gait parameters did not correlate in either gender. Conclusion There were no interactions between FMS, gait parameters, and gender; however, correlation analyses support the idea that strength and conditioning coaches need to pay attention not only to how to score but also how to correctly use FMS.

Adipokines as atherothrombotic risk factors in obese subjects: Associations with haemostatic markers and common carotid wall thickness.

BACKGROUND AND AIMS: Some crucial associations between obesity-related altered adipokine levels and the main factors of atherosclerotic, atherothrombotic processes are not fully known. We analysed the relationships of classic adipokines, namely leptin, resistin, adiponectin, tumour necrosis factor-alpha (TNF-α), interleukin 6 (IL-6) with the markers of platelet activation, including mean platelet volume (MPV), platelet surface/soluble P-selectin, platelet-derived microparticles (PMPs), the parameters of coagulation abnormalities and common carotid intima-media thickness (IMT) in obese patients with or without atherosclerotic comorbidities in comparison to age- and sex-matched controls. METHODS AND RESULTS: We enrolled 154 obese individuals, including 98 suffering from atherosclerotic concomitant conditions, 56 free of atherosclerotic comorbidities and 62 healthy controls. Plasma levels of leptin, resistin, adiponectin, TNF-α, IL-6, soluble P-selectin, and plasminogen activator inhibitor-1 antigen (PAI-1 ag) were analysed by ELISA. Platelet surface P-selectin and PMPs were measured by flow cytometry. IMT was detected by ultrasonography. Adipokines were closely associated with markers of platelet hyperactivity, hypercoagulability, hypofibrinolysis and IMT. Significant independent associations were found between leptin and platelet count (p < 0.0001), MPV (p = 0.019), PMPs (p < 0.0001), fibrinogen (p = 0.001), factor VIII (FVIII) activity (p = 0.035); adiponectin and PAI-1 ag (p = 0.035); resistin and soluble P-selectin (p = 0.002); TNF-α and PAI-1 ag (p < 0.0001); and IL-6 and fibrinogen (p = 0.011). Finally, leptin (p = 0.0005), adiponectin (p = 0.019), IL-6 (p = 0.001), MPV (p = 0.0003), PMP (p = 0.008), and FVIII activity (p = 0.043) were independent predictors of IMT. CONCLUSION: Overall, we suggest that in obese subjects altered adipokine levels play a key role in common carotid atherosclerosis both directly and through haemostatic parameters.

Variants in the CNR1 gene predispose to headache with nausea in the presence of life stress.

One of the main effects of the endocannabinoid system in the brain is stress adaptation with presynaptic endocannabinoid receptor 1 (CB1 receptors) playing a major role. In the present study, we investigated whether the effect of the CB1 receptor coding CNR1 gene on migraine and its symptoms is conditional on life stress. In a cross-sectional European population (n = 2426), recruited from Manchester and Budapest, we used the ID-Migraine questionnaire for migraine screening, the Life Threatening Experiences questionnaire to measure recent negative life events (RLE), and covered the CNR1 gene with 11 SNPs. The main genetic effects and the CNR1 × RLE interaction with age and sex as covariates were tested. None of the SNPs showed main genetic effects on possible migraine or its symptoms, but 5 SNPs showed nominally significant interaction with RLE on headache with nausea using logistic regression models. The effect of rs806366 remained significant after correction for multiple testing and replicated in the subpopulations. This effect was independent from depression- and anxiety-related phenotypes. In addition, a Bayesian systems-based analysis demonstrated that in the development of headache with nausea all SNPs were more relevant with higher a posteriori probability in those who experienced recent life stress. In summary, the CNR1 gene in interaction with life stress increased the risk of headache with nausea suggesting a specific pathological mechanism to develop migraine, and indicating that a subgroup of migraine patients, who suffer from life stress triggered migraine with frequent nausea, may benefit from therapies that increase the endocannabinoid tone.

An investigation of rainwater tanks quality and sediment dynamics.

Rainwater tanks are being introduced into urban areas in Australia to supplement centralised potable supply systems. A pilot scale tank study and a full-scale field tank study found that heavy metal concentrations in water samples taken from the tank's supply point can, in some cases, exceed levels recommended by guidelines. Both studies also found very high concentrations of heavy metals in the sediments accumulated at the base of rainwater tanks. Laboratory experiments are underway to investigate sediment transport processes within a full-scale tank. Preliminary results demonstrate the effect of sediment resuspension on the quality of water released from the tank outlet. Improved tank designs that reduce sediment resuspension and mitigate impacts on water quality are the focus of future work.

Carotid artery auscultation--anachronism or useful screening procedure?

Carotid bruits are supposed to indicate the presence of high-grade common carotid or extracranial internal carotid artery stenosis in a large proportion of patients. Using a stethoscope, we prospectively auscultated 273 carotid arteries of 145 patients blinded to the results of a complete extracranial and intracranial Doppler investigation including extracranial color-coded duplex ultrasound. Fifty-four arteries showed stenosis of > or = 50%-99%, or occlusion of the extracranial internal or the common carotid artery. In 25 of these arteries, a bruit was present. In 9 out of 16 patients with extracranial stenosis from 70%-99%, a bruit was detected. In one additional patient with a middle-grade external carotid artery stenosis, a bruit was also present. In seven additional patients, a bruit was present in the absence of any carotid artery stenosis, cardiac vitium or goiter. The sensitivity of carotid auscultation for the detection of a 70%-99% stenosis of the common or extracranial internal carotid artery was 56% and specificity was 91%. The positive predictive value of a bruit found during carotid auscultation was 27%, and the negative predictive value of a normal auscultation was 97%. Carotid auscultation is a useful screening procedure in the detection of carotid stenosis or occlusion, but requires confirmation by carotid ultrasound.

Transcranial Doppler monitoring in hypertensive patients during physical exercise.

PURPOSE: To evaluate the diagnostic value of a combined method, i.e. ergometer cycling with continuous bilateral transcranial Doppler monitoring (TCD) to detect cerebral hemodynamic abnormalities in recently diagnosed hypertensive patients. METHODS: 30 neurologically symptom-free, nontreated patients with essential hypertension and 30 age- and sex-matched controls were studied. Carotid ultrasound, resting ECG and blood parameters were investigated. Cycling ergometry was performed according to the WHO protocol. Blood pressure, heart rate, end-tidal CO2 (etCO2) and bilateral middle cerebral artery (MCA) blood flow velocity (MV) were monitored. RESULTS: At rest, MV in the MCA did not differ significantly between controls and hypertensive subjects. MV continuously increased in controls until the end of loading whereas a plateau was reached at 4 min in hypertensive subjects. During 6 min of cycling, the time course of absolute values of MV in the MCA and that of the changes in the ratio of mean velocity/end-tidal CO2 (DeltaMV/DeltaetCO2) differed significantly between hypertensive subjects and controls (p = 0.03 and p = 0.02, respectively). CONCLUSION: Ergometer cycling combined with TCD revealed altered vasoreactivity, therefore this may be a sensitive method for the detection of early hemodynamic impairment in nontreated hypertensive subjects.

[T gamma-lymphoproliferative disease]. / T gamma-lymphoproliferatív betegség.

The case of a rare type of T-cell malignant lymphomas, clinically with a relatively favorable course, a T gamma-lymphoproliferative disease (T gamma-cell chronic lymphocytic leukaemia) was presented. The cytomorphological, cytochemical, immuncytochemical and cytogenetical markers and functional tests of the peripheral blood lymphocytes from the patient were tested. The leukaemic cells with light- and electron microscopy showed the so called LGL (large granular lymphocyte) morphology with multifocal reactions of acid hydrolase enzymes. These cells also expressed IgG-Fc-receptor, CD 8 monoclonal antibody positivity and a monoclonally rearranged T-cell receptor gen expression. Functionally the patient's lymphocytes developed a blastic response to the T-cell mitogen Concanavalin A (ConA), they suppressed the immunoglobulin production of B-lymphocytes in co-cultures and had a normal NK-activity but decreased ADCC values. The patient was diagnosed by blood, bone marrow and lymph node examination and does not need any therapy. This case was published because of it's diagnostic, immunological and prognostical interests.

[Gene rearrangement in leukemia]. / Génátrendezödés leukaemiákban.

In this report we summarize our experiences based on the gene rearrangement study of 111 leukaemic patients of different kind. The lymphocyte DNA of the patients was studied for rearrangement of the immunoglobulin light chain constant-, the heavy chain joining- and the T cell receptor beta chain constant region. Our data have well supplemented the results of the monoclonal antibody experiments. In 33 cases the DNA study was in good agreement with the immunological data. In 42 our data helped in gave different results, immunological results. In 11 cases evaluating the DNA and immunological data indicating the necessity of further investigation. The results were inconclusive in 25 cases. As a conclusion we consider the gene rearrangement study to be useful for diagnostic purposes.

Bigenotypic and biphenotypic appearance of immunoglobulin light chains in 1 of 3 non-Hodgkin's lymphoma xenografts.

Chromosomal analysis of three human non-Hodgkin's lymphoma (NHL) xenografts revealed common extra 14q+ segment and other individual clonal markers without involvement of immunoglobulin light-chain regions. Two NHL xenografts (HT 58 and HT 130) showed restricted lambda light chain expression and deleted kappa and rearranged lambda genes. However, in HT 117 both kappa and lambda chains were present on the cell surface, and both light chain genes showed rearranged alleles. This unique phenomenon could have resulted from either disturbed regulation of isotype exclusion or from the malignant transformation of light chain 'uncommitted' B cells.

Clinical value of cytomorphologic, immunologic and cytogenetic investigations of acute leukaemias.

The valuability of immunophenotyping of acute myeloid and lymphoid leukaemias in comparison to morphological and cytochemical classification were approached in 56 cases. In the case of acute myeloid leukaemias the immunophenotyping by monoclonal antibodies CD14, CD13, CD33 was less informative concerning the subtypes of the disease. The clinical diagnosis can be achieved on the basis of cytochemical investigation alone. In contrast, the diagnosis of lymphoid leukaemias requires all information obtained by immunophenotyping by a series of monoclonal antibodies CD3, CD2, CD4, CD8, CD1, CD19, CD20, CD21 and CD10. On the other hand, the monoclonal antibodies are essential in differentiation of the very immature myeloid and lymphoid leukaemias. This is of great importance from the clinical point of view for determining the therapy. Molecular genetic studies based on the characterisation of the state of gene rearrangement of immunoglobulin and T-cell receptor beta chains have basic importance in the confirmation of the result of immunophenotyping and in the determination of leukaemias of unknown origin.

[Hygienic-bacteriological examinations in station restaurants (author's transl)]. / Hygienisch-bakteriologische Untersuchungen in Bahnhofsrestaurants.

In four station restaurants (West station, East station, South station, Kelenföld station) microbiological examinations were carried out in conjunction with the inspection of the hygienic conditions. The microflora of the washed and dried drinking glasses and plates as well as the smocks of the kitchen staff were examined. Intestinal bacteria, chromogenic bacteria and pathogenic staphylococci were found in numerous crockery samples. Therefore, it is necessary either to improve the effectiveness of the cleaning process or to prolong the drying of the crockery by heat. Numerous species, such as intestinal bacteria, chromogenic bacteria liable to cause food-decomposition were found in the kitchen staff's smocks, sometimes even in great quantities. To reliably determine the microbiological limit values for smocks and other textiles, a great number of examinations are still necessary. The smocks of the staff handling pre-cooked meals, cold meals or pastries must also be microbiologically clean.--The medical activity in the areas mentioned proved also beneficial to the training in hygiene.

The role of alkalication in formation and decomposition of myosin-ATP complex.

The dependence of kinetic constants Km, V(k2) and k1 of myosin-ATPase on the species and concentration of alkali cations and on temperature was investigated. The value of Vvaries with the ionic radius of different alkali cations. The curve has a maximum at 1.33 A at the ionic radius of potassium. The detailed analysis of the cation dependence of the kinetics of the ATPose reaction shows that both formation and decomposition of the complex are affected by the cation present.