Taxonomic distribution and origins of the extended LHC (light-harvesting complex) antenna protein superfamily

Background  

The extended light-harvesting complex (LHC) protein superfamily is a centerpiece of eukaryotic photosynthesis, comprising the LHC family and several families involved in photoprotection, like the LHC-like and the photosystem II subunit S (PSBS). The evolution of this complex superfamily has long remained elusive, partially due to previously missing families.     

COMPARISON OF THE BEHAVIOUR OF A SOLUBLE AND A MEMBRANE-BOUND ENZYME IN TRANSECTED PERIPHERAL NERVES

Phosphoglucoisomerase (PGI), a soluble enzyme, and AChE, a membrane-bound enzyme were studied in transected peroneal nerves of dog and in isolated segments of these nerves. Although activities of both enzymes increased at the ends of transected nerves, marked differences in their behaviour were observed. The increment in AChE activity was much sharper than that of PGI and continued to grow with time whereas the increase in PGI developed fully within the initial hours after transection and did not change thereafter. In an isolated nerve segment AChE accumulated at both ends with a concomitant decrease in the middle part, whereas changes in PGI activity appeared only in the terminal parts, the rest of the nerve remaining at the normal level. The terminal increase of PGI did not, contrary to that of AChE, depend on the length of the isolated segment. The changes in PGI activity may be features of a local peritraumatic reaction whereas those of AChE indicate involvement of the whole segment along which the enzyme containing organelles are transported.     

Localization of neurosecretion in the nervous system of Catenulida (Turbellaria)

Summary The nervous system of the most primitive fresh-water Turbellaria of the order Catenulida was investigated. Neurosecretory cells were found to occur in it. These cells have a structure similar to that of nerve cells, they only differ by the presence of neurosecretion granules and a more developed golgi complex. In the simplest Catenulida,Stenostomun, neurosecretory granules are found both in the brain cells and in the trunks in the nerve fibres where they are rather randomly distributed. Another representative of this family, the more highly organizedCatenula, exhibits specialized brain and nerve trunk regions containing neurosecretion granules. This work was supported in part by the Committee on Cytobiology of the Polish Academy of Sciences     

Prototypic sequences for human repetitive DNA

Summary We report a collection of 53 prototypic sequences representing known families of repetitive elements from the human genome. The prototypic sequences are either consensus sequences or selected examples of repetitive sequences. The collection includes: prototypes for high and medium reiteration frequency interspersed repeats, long terminal repeats of endogenous retroviruses, alphoid repeats, telomere-associated repeats, and some miscellaneous repeats. The collection is annotated and available electronically.[/ap ]Offprint requests to: J. Jurka     

Effect of angiotensin II and norepinephrine on release of prostaglandins E2 and I2 by the perfused rat mesenteric artery

Prostaglandin E₂ (PGE₂) and 6 keto-PGF_1α, the stable metabolite of prostacyclin (PGI₂), have been measured in the effluent of perfused rat mesenteric arteries by the use of a sensitive and specific radioimmunoadday (RIA) method. The PGE₂ and 6-keto-PGF_1α were continuousyl released by the unstimulated mesenteric artery over a period of 145 min. After 100 min of perfusion the release of PGE₂ and 6-keto-PGF_1α was 4.5 ± 8.4 pg/min and 254 ± 75 pg.min respectively, which is in accord with the general belief that PGI₂ is the major PG synthesized by arterial tissue. Angiotensin II (AII) 5 ng/ml) induced an increased of PGE₂ and 6-keto-PGF_1α release without changing the perfusion pressure. The effect of norepinephrine (NE) injections on release of PGs depended on the duration of the stabilization period. The changes of perfusion pressure induced by NE were not related to changes in release of PGs. Thus, it seems that the increase of PG release induced by AII and NE was due to a direct effect of the drugs on the vascular wall. This may represent an important modulating mechanism in the regulation of vascular tone.     

The effect of new non-cross resistant antitumour agents on the energy state of human erythrocytes

Multidrug resistance (MDR) of tumour cells is related to the overexpression of ATP-dependent pumps responsible for the active efflux of antitumour agents out of resistant cells. Benzoperimidine and anthrapyridone compounds exhibit comparable cytotoxic activity against sensitive and MDR tumour cells. They diffuse extremely rapidly across the plasma membrane and render the ATP-dependent efflux inefficient. Such uptake could disturb an energy metabolism of normal cells possessing an elevated level of ATP-dependent proteins, especially erythrocytes having a high level of the MRP1, MRP4 and MRP5 proteins. In this study the effect of five antitumour agents: benzoperimidine (BP1), anthrapyridones (CO1, CO7) and reference drugs used in the clinic: doxorubicin (DOX) and pirarubicin (PIRA), on the energetic state in human erythrocytes has been examined. These compounds have various types of structure and kinetics of cellular uptake (slow--DOX, CO7, moderate--PIRA, fast--BP1, CO1) resulting in their different ability to saturate ATP-dependent transporters. The energetic state of erythrocytes was examined by determination of purine nucleotide contents (ATP, ADP, AMP), NAD(+) and values of adenylate energy charge (AEC) using an HPLC method. It was found that the level of nucleotides as well as the AEC value of erythrocytes were not changed during 24 h of incubation with these agents independently of their structure and ability to saturate ATP-dependent pumps. This is a very promising result in view of their potential use in the clinic as antitumour drugs against multidrug resistant cancers.     

Synthesis,receptor binding studies,optical spectroscopic and in silico structural characterization of morphiceptin analogs with cis‐4‐amino‐L‐proline residues

Three novel morphiceptin analogs, in which Pro in position 2 and/or 4 was replaced by cis‐4‐aminoproline connected with the preceding amino acid through the primary amino group, were synthesized. The opioid receptor affinities, functional assay results, enzymatic degradation studies and experimental and in silico structural analysis of such analogs are presented. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.     

Effect of Garlic Supplementation on Erythrocytes Antioxidant Parameters, Lipid Peroxidation, and Atherosclerotic Plaque Formation Process in Oxidized Oil-Fed Rabbits

Effect of garlic supplementation on blood antioxidant status, lipid peroxidation, and coronary plaque formation process was investigated in oxidized oil-fed rabbits. Eighteen adult male mixed European rabbits were given a balanced diet (21 g% protein, 34 g% fat, 45 g% carbohydrate), which contained isocaloristic addition of nonoxidized or oxidized rapeseed oil in the presence and absence of garlic. The experiment lasted 24 weeks. At the beginning and every 6 weeks, rabbits were weighed, and blood was taken. To evaluate the antioxidant status of the rabbits, erythrocytes malondialdehyde (MDA) concentration, total superoxide dismutase (t-SOD), and glutathione peroxidase (GPX) activations were determined. After the experiment was completed, aortas were dissected for histological examinations. Changes in the contents of the above parameters and histological examinations showed that oxidized rapeseed, oil administered to rabbits, caused the development of atherosclerotic changes and disturbed antioxidant status. The addition of garlic in such diets inhibited atherosclerotic changes in the aorta wall, and it is related to the homeostatic activity of antioxidative enzymes and lipid peroxidation.     

Completion total thyroidectomy in children with differentiated thyroid cancer

INTRODUCTION: The optimal surgical treatment of children with differentiated thyroid cancer remains an important point of discussion. Especially the need for completion operation is questioned in young patients. Our objective was to examine the rate of residual neoplastic disease after non radical initial operation. MATERIAL AND METHODS: From the 235 children diagnosed with differentiated thyroid cancer, 131 (56%) needed completion operation due to incomplete primary surgery. Completion operation involved thyroid bed, lymph nodes or both respectively in 91 (39%), 13 (6%) and 27 (11%) cases. Risk factors responsible for residual disease were evaluated by means of logistic regression analysis. RESULTS: Residual disease was detected in 46 (35%) of reoperated children (25% in thyroid bed and 85% in lymph node of lateral neck compartment). Sex and age did not influence the risk of residual disease in thyroid bed or lymph nodes. Papillary type of cancer and multifocality increased risk of residual disease in thyroid bed respectively by the factor of 15 (95% CI: 2-125) and 2.3 (95% CI: 1.2-4.4). Infiltration of thyroid capsule did not correlate with the risk of residual disease. Lymph node metastases in primary operation increased risk of residual disease by the factor of 16 (95% CI: 1.2-245). Histopathology, multifocality of primary tumour or infiltration of lymph node capsule did not influence the risk of residual disease in lymph nodes of lateral neck compartment. CONCLUSIONS: In children with differentiated thyroid cancer residual disease is diagnosed in about 1/3 of non radically operated cases. This high incidence justifies completion operations. The risk of residual disease is significantly increased in papillary thyroid cancer, multifocal tumours and cases with lymph node metastases.