Early detection of plant stress from changes in distributions of chlorophyll a fluorescence parameters measured with fluorescence imaging.

In this work, we used barley leaves suffering from a stress, for measurements of chlorophyll a fluorescence with an imaging fluorometer. We compared selected fluorescence parameters (FP) determined from the measurements of control (no stress) and afterwards stressed sample by classical statistical comparison (Mann-Whitney test) and by statistical comparison of shapes of distributions of the FPs (two-sample Smirnov test). We have found that there exist examples where statistically significant difference is not revealed using the classical statistical comparison (for given critical level), but statistically significant difference is revealed using comparisons of distributions (for the same critical level).

The polyphasic chlorophyll a fluorescence rise measured under high intensity of exciting light.

Chlorophyll a fluorescence rise caused by illumination of photosynthetic samples by high intensity of exciting light, the O-J-I-P (O-I-I-P) transient, is reviewed here. First, basic information about chlorophyll a fluorescence is given, followed by a description of instrumental set-ups, nomenclature of the transient, and samples used for the measurements. The review mainly focuses on the explanation of particular steps of the transient based on experimental and theoretical results, published since a last review on chlorophyll a fluorescence induction [Lazár D (1999) Biochimica et Biophysica Acta 1412, 1-28].

High-Temperature Induced Chlorophyll Fluorescence Rise in Plants at 40-50 degrees C: Experimental and Theoretical Approach.

We studied the temperature dependence of chlorophyll fluorescence intensity in barley leaves under weak and actinic light excitation during linear heating from room temperature to 50 degrees C. The heat-induced fluorescence rise usually appearing at around 40-50 degrees C under weak light excitation was also found in leaves treated with 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU) or hydroxylamine (NH(2)OH). However, simultaneous treatment with both these compounds caused a disappearance of the fluorescence rise.

Rare forms of peripheral arterial embolism: review of 11 cases.

The purpose of this study was to present 11 patients operated on owing to rare forms of peripheral arterial embolism at the Institute for Cardiovascular Diseases of the Serbian Clinical Center over a period of 20 years. Three patients were operated on owing to a foreign body embolism, two owing to a septic embolism, three owing to emboli that originated from malignant tissues, two owing to an embolization from cardiac myxoma, and one owing to an embolism from a myxomatous atrial septal defect. The preoperative evaluation included clinical examination, laboratory findings, and electrocardiography; in the majority of cases, ultrasonography and angiography were performed.

Experimental and theoretical studies on the excess capacity of Photosystem II.

It has been recently suggested that compensatory changes in Photosystem II (PS II) electron turnover rates can protect photosynthesis from photoinhibition [Behrenfeld et al. (1998) Photosynth Res 58: 259-268]. We have further explored this feature of PS II using a rate electrode for simultaneous measurements of the steady-state rate of oxygen evolution and the oxygen flash yield depending on the background irradiance in both control and photoinhibited algal cells of Chlorella Böhm.

Thermoluminescence and fluorescence study of changes in Photosystem II photochemistry in desiccating barley leaves.

An effect of desiccation (a decrease of relative water content from 97% to 10% within 35 h) on Photosystem II was studied in barley leaf segments (Hordeum vulgare L. cv. Akcent) using chlorophyll a fluorescence and thermoluminescence (TL).

Determination of the antenna heterogeneity of Photosystem II by direct simultaneous fitting of several fluorescence rise curves measured with DCMU at different light intensities.

Several methods for determination of the antenna heterogeneity of Photosystem II from fluorescence rise curves measured with DCMU have been developed so far. Using these methods, two, three or four types of Photosystem II with respect to the antenna heterogeneity were determined. However, the accuracy of some of these methods is under debate.

Do cystometric findings predict the results of intravesical hyaluronic acid in women with interstitial cystitis?

Introduction And Objectives: According to National Institute of Health (NIH) criteria, a bladder capacity of less than 350 cc is an automatic exclusion for a diagnosis of Interstitial Cystitis (IC). In the present study, patients, showing symptoms of IC and with bladder capacities of <350 and >/=350 cc were tested as to their response to a intravesical hyaluronic acid therapy.

Methods: The study included 48 patients with clinical symptoms of IC and a positive 0.

p53 tumoral supressor gene expression and significance in endometrial cancer.

p53 tumoral suppressor gene is the most frequent mutant gene identified till now in human neoplasias. Conformational transformations induced by these genes are associated with the stabilization of the p53 gene product and with the accumulation of the mutant protein in the malignant cells nuclei, in quantities which can be immunohistochemically detected. The goal of this paper is to immunohistochemically exam p53 protein expression in 15 patients with primary endometrial carcinomas, using anti-p53 monoclonal antibody (DO7), antibody which can detect the savage form and the mutant form of p53 protein.

Prognostic significance of c-erbB2 protein in endometrial cancer.

The human protooncogene c-erbB2, also known as HER-2/neu is sited on 17q21 chromosome and codifies a transmembranous glycoprotein of 185 KD, named c-erbB2 protein, with tyrosin-kinasic activity and homologue from molecular point of view with the epidermal growth factor receptor (EGFR). In order to detect the tissular expression of c-erbB2 protein, tissular samples from 10 patients with primary endometrial cancer were immmunohistochemically processed. C-erbB2 immunostaining using c-erbB2 (21N) antiserum marked the cellular membranes and, occasionally, the cytoplasma of the tumoral cells.

A theoretical study on effect of the initial redox state of cytochrome b559 on maximal chlorophyll fluorescence level (F(M)): implications for photoinhibition of photosystem II.

In this work, we extended the reversible radical pair model which describes energy utilization and electron transfer up to the first quinone electron acceptor (Q(A)) in photosystem II (PSII), by redox reactions involving cytochrome (cyt) b559. In the model, cyt b559 accepts electrons from the reduced primary electron acceptor in PSII, pheophytin, and donates electrons to the oxidized primary electron donor in PSII (P680+). Theoretical simulations of chlorophyll fluorescence rise based on the model show that the maximal fluorescence, F(M), increases with an increasing amount of initially reduced cyt b559.

Structure-activity relationships in 4- and 5-androstene: 3beta-acetoxy-17-methyl-17-oxo-16,17-seco-5-androstene-16-carbonitrile and 17-methyl-3,17-dioxo-16,17-seco-4-androstene-16-carbonitrile.

The title compounds, C22H31NO3 and C20H27NO2, have similar conformations except in the molecular geometry and the bonding of two of the rings. These differences lead to marked differences in the biological activities of these compounds. Molecules of both compounds are linked by weak C-H.

Accurate intraoperative localization of spinal dural arteriovenous fistulae with embolization coil: technical note.

Spinal dural arteriovenous fistulae represent a potentially curable cause of a progressive myelopathy and therefore should be treated aggressively by either endovascular or surgical methods. In the surgical treatment of these lesions, intraoperative radiographic localization of the site of the fistula can be problematic. We describe an endovascular technique in which radiopaque microcoils are placed in the major feeding artery(ies) after completion of spinal angiography, which then provides a marker that is easily visualized with intraoperative x-rays, allowing effective localization of the site of the fistula.

[Cyclodextrins implications in drugs control and analysis].

The discovery and development of substances require new forms at a level which was considered satisfactory a few years ago. The research on secondary effects and drugs optimizations to new pharmaceutical forms. So, we can speak about the inclusion complexes.

Synthesis, structure, and screening of estrogenic and antiestrogenic activity of new 3,17-substituted-16,17-seco-estratriene derivatives.

The starting compound for synthesis of new 16,17-seco-estratriene derivatives was 3-benzyloxy-17-hydroxy-16,17-secoestra-1,3,5(10)-triene-16-nitrile (1b), obtained from estrone in several synthetic steps. 17-Tosyl, -chloro-, bromo-, and -iodo- derivatives 2b, 4b, 5b, and 6b were prepared directly from secocyanoalcohol 1b, while the 17-fluoro-derivative 3b was obtained from tosylate 2b in the reaction with tetrabutyl ammonium fluoride. The corresponding 3-hydroxy derivatives of these compounds were produced by action of hydrogen in presence of Pd/C, except the 3-hydroxy-17-iodo derivative 6a, which was obtained from 3-hydroxy-17-tosyloxy derivative 2a.

Synthesis, X-ray crystal structures and biological activity of 16-amino-17-substituted-D-homo steroid derivatives.

D-Homo derivatives in the androstane and estrane series, 12-19, were synthesized by a fragmentation-cyclization reaction of 16-oximino-17-hydroxy-17-substituted derivatives 3-9, or by cyclization of the corresponding D-seco derivatives 20-26. The structures were confirmed by X-ray analysis of compounds 12 and 16. Preliminary assessment of inhibitory effects of D-homo derivatives from androstane series towards aromatase, 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD), 17 alpha-hydroxylase/C17-20 lyase (P450c17) and 17 beta-HSD indicated much lower inhibitory potential compared to previously tested activity of another type of D-modified steroids, namely D-seco derivatives.

High-resolution magnetic resonance imaging is a noninvasive method of observing injury and recovery in the peripheral nervous system.

Objective: Noninvasive observation of degenerating and regenerating peripheral nerves could improve the diagnosis and treatment of nerve injuries. We constructed a novel phased-array radiofrequency coil to permit magnetic resonance imaging (MRI) observation of the sciatic nerve and its target muscles in rats after injury.

Methods: Adult male Lewis rats underwent either crushing (n = 18) or cutting and capping (n = 17) of their right sciatic nerves and then underwent serial MRI.

Hemorrhagic complications of intracranial pressure monitors in children.

Intracranial pressure (ICP) monitoring plays a valuable role in the management of head injuries and other causes of raised ICP in the pediatric population. The purpose of this study was to investigate the incidence of hemorrhage after ICP monitor insertion, and to classify these complications in a clinically relevant manner. Hospital charts of 431 children (ages 0-16 years) admitted to a level I trauma center over a 2-year period were reviewed and 112 patients (134 insertions) who underwent intraparenchymal ICP monitoring were identified.

Chlorophyll a fluorescence rise induced by high light illumination of dark-adapted plant tissue studied by means of a model of photosystem II and considering photosystem II heterogeneity.

Chlorophyll a fluorescence rise (FLR) measured in vivo in dark-adapted plant tissue immediately after the onset of high light continuous illumination shows complex O-K-J-I-P transient. The steps typically appear at about 400 micros (K), 2 ms (J), 30 ms (I), and 200 - 500 ms (P) and a transient decrease of fluorescence to local minima (dips D) can be observed after the K, J, and I steps. As the FLR reflects a function of photosystem II (PSII) and to more understand the FLR, a PSII reactions model was formulated comprising equilibrium of excited states among all light harvesting and reaction centre pigments and P680, reversible radical pair formation and the donor and acceptor side functions.

Comparison of homoeologous group-6 short arm physical maps of wheat and barley reveals a similar distribution of recombinogenic and gene-rich regions.

Eighty two new loci, mapped with 51 DNA clones, were added to the earlier deletion maps of the homoeologous group-6 short arms of hexaploid wheat ( Triticum aestivum L. em Thell., 2n = 6 x = 42, AABBDD).

D-Secoestrone derivatives. VI. 17 beta-Benzyl-17 alpha-hydroxy-3-methoxyestra-1,3,5(10)-trien-16-one.

The title molecule, C(26)H(30)O(3), shows a novel chemical rearrangement of the substituents at position 17, i.e. an alpha-orientation of the hydroxy group and a beta-orientation of the bulky benzyl moiety.

D-Secoestrone derivatives. V1. 3-Methoxy-17-oxo-17-phenyl-16,17-secoestra-1,3,5(10)-triene-16-nitrile and 17-hydroxy-3-methoxy-17-phenyl-16,17-secoestra-1,3,5(10)-triene-16-nitrile.

The two title 16,17-secoestrone derivatives, 3-methoxy-17-oxo-17-phenyl-16,17-secoestra-1,3,5(10)-triene-16-nitrile, C(25)H(27)NO(2), (I) (17-oxo substituent), and 17-hydroxy-3-methoxy-17-phenyl-16,17-secoestra-1,3,5(10)-triene-16-nitrile, C(25)H(29)NO(2), (II) (17-hydroxy substituent), have quite different conformations in the solid state. These conformational differences can be minimized by molecular mechanics calculations. Thus, the remarkable difference in the biological activity of the two compounds, e.

Acceleration of recovery after injury to the peripheral nervous system using ultrasound and other therapeutic modalities.

Taken together, these studies show the promise of various therapeutic modalities for the noninvasive treatment of peripheral nerve injury. Further progress on these promising methods requires determining the biologic mechanisms responsible for the ability of these modalities to enhance peripheral nerve recovery. Necessary investigations include validation or refutation of the hypothesis that these therapies act on various aspects of the natural healing process.

Analgesia elicited by OFQ/nociceptin and its fragments from the amygdala in rats.

The heptadecapeptide, orphanin FQ/nociceptin (OFQ/N), binds with high affinity to the ORL-1/KOR-3 opioid receptor clone, yet binds poorly with traditional opioid receptors. OFQ/N has a complex functional profile with relation to nociceptive processing, displaying pro-nociceptive properties in some studies, acting as an inhibitor of stress-induced analgesia in others, yet producing both spinal and supraspinal antinociceptive actions in other studies. Among the intracerebral sites at which OFQ/N might produce one or more of these actions is the amygdala which has been intimately implicated in both antinociceptive and stress-related responses.