Homodimeric monomethine cyanine dyes as fluorescent probes of biopolymers.

The fluorescence properties of newly synthesized homodimeric monomethine cyanine dyes in the presence of biopolymers are investigated. They do not fluoresce in TE buffer and bidistilled water but become strongly fluorescent (Q(F)=0.3-0.9) in the region 530-650 nm when bound to dsDNA and ssDNA. The detection limit of dsDNA is about 1.7 ng/ml. Some of dyes studied are able to distinguish between dsDNA and ssDNA, RNA, BSA in solution and gel electrophoresis. The influence of different factors (temperature, pH and viscosity of the medium, presence of histone) on the formation of the dye-biopolymer complexes is investigated. The results of steady-state and dynamic fluorescence measurements concerning the different types of binding between dyes and biopolymers show that the new dyes are applicable in molecular biology as highly sensitive fluorescence labels.

Sodium pyruvate infusions in patients with alcoholic liver disease. Preliminary report.

Pyruvate has been shown to benefit cellular energy metabolism and to reduce free radical formation. Concerning gastrointestinal side effects of orally administered sodium pyruvate, in this pilot study we investigated the therapeutic effectiveness of sodium pyruvate infusions in patients with alcoholic liver disease (ALD). Fifteen patients with ALD received sodium pyruvate infusions for: (1) 10 days (54-86.4 g pyruvate daily, 150-180 mg/min., 6-8 h); and (2) 15 days (50-54 g daily, 100 mg/min., 6 h). Sodium pyruvate treatment resulted in significantly decreased serum AST (p<0.03), ALT (p<0.03), AP (p<0.004), GGT (p<0.05), and total bilirubin (p<0.04). Improvement of liver function was also evident from the significantly decreased Combined Clinical and Laboratory Index (from 6.50+/-0.71, to 3.92+/-0.84, p<0.001), and Liver Damage Score (from 3.83+/-0.71 to 2.75+/-0.58, p<0.01). The two therapy schedules used showed similar results. Unchanged serum pyruvate, lactate, and glucose confirmed the good utilization of pyruvate. Tolerance of sodium pyruvate treatment was very good in 26.09% and good in 68.94% of the observations. Our results showed good therapeutic effectiveness and good tolerance of sodium pyruvate infusions in patients with ALD. This is possibly due to the rapid gain of ATP and GTP, required to redress defective cells, and to antioxidant action of pyruvate.

Hereditary motor and sensory neuropathy--Lom, a novel demyelinating neuropathy associated with deafness in gypsies. Clinical, electrophysiological and nerve biopsy findings.

A previously unrecognized neuropathy was identified in Bulgarian gypsies, and was designated hereditary motor and sensory neuropathy-Lom (HMSNL) after the town where the initial cases were found. It was subsequently identified in other gypsy communities. The disorder, which is of autosomal recessive inheritance, was mapped to chromosome 8q24. It begins consistently in the first decade of life with gait disorder followed by upper limb weakness in the second decade and, in most subjects, by deafness which is most often first noticed in the third decade. Sensory loss affecting all modalities is present, both this and the motor involvement predominating distally in the limbs. Skeletal deformity, particularly foot deformity, is frequent. Severely reduced motor nerve conduction velocity indicates a demyelinating basis, which was confirmed by nerve biopsy. The three younger patients biopsied showed a hypertrophic 'onion bulb' neuropathy. The hypertrophic changes were not evident in the oldest individual biopsied and it is likely that they had regressed secondarily to axon loss. In the eight cases in which brainstem auditory evoked potentials could be recorded, the results suggested demyelination in the eighth cranial nerve and also abnormal conduction in the central auditory pathways in the brainstem. As no myelin genes are known to be located at chromosome 8q24, the disorder may involve a gene for a novel myelin protein or be due to an abnormality of axon-Schwann cell signalling.

Gene mapping in Gypsies identifies a novel demyelinating neuropathy on chromosome 8q24.

Founder effect and linkage disequilibrium have been successfully exploited to map single gene disorders, and the study of isolated populations is emerging as a major approach to the investigation of genetically complex diseases. In the search for genetic isolates ranging from Pacific islands to Middle East deserts, the 10 million Gypsies resident in Europe have largely escaped the attention of geneticists. Because of their geographical ubiquity, lack of written history and the presumed social and cultural nature of their isolation, Gypsies are construed as not meeting the criteria for a well defined founder population. Gypsy society has a complex structure with subdivisions and stratifications that are incomprehensible to the surrounding populations. Marginalization by the health care systems in most countries results in a lack of information on causes of morbidity and mortality and little is known about hereditary disorders or the population genetic characteristics of Gypsies. This study is the first example of mapping a disease gene in endogamous Gypsy groups. Using lod score analysis and linkage disequilibrium, we have located a novel demyelinating neuropathy to a narrow interval on chromosome 8q24. We show that the disease, occurring in Gypsy groups of different identity and history of migrations, is caused by a single mutation whose origin predates the divergence of these groups.

Pharmacokinetic investigation with 125I labeled T-actemodulin (TAM).

The aim of the study was to label TAM with radioactive iodine and to follow its distribution in different organs of rats. T-actemodulin is a thymic hormone isolated from calf thymus by a new technology. TAM was labeled according to the method of Greenwood and Hunter. Two major peaks were observed on the gel chromatography: The first peak contained the labeled TAM; the second peak contained 125I which was not bound to the organic compound. Additional purification of the first peak was performed on a Sephadex G-75 column, and the eluate was designated as purified peak I. After a radioimmune testing it could be concluded that TAM was labeled successfully and the peak I contained 125I-TAM. Peak I, purified peak I and the peak II were applied to young male Wistar rats. The radioactivity of pancreas, kidney, spleen, adrenals, liver, thymus, bone marrow, testis and thyroid were measured after killing the animals 10 min, 60 min, and 24 h after the injections. The pharmacokinetic study showed that all organs, except for the thyroid have a higher affinity for labeled TAM than for the free 125I. Higher accumulation of labeled TAM was observed in the pancreas, kidney, adrenals and spleen. A specific uptake of labeled TAM in these organs can be suggested. Functional interrelations between thymus and pancreas, spleen, adrenals are discussed.

Immunohistochemical and electron microscope studies of rat islets of Langerhans one month after adult thymectomy.

Ultrastructural and quantitative immunocytochemical studies of rat pancreata were carried out 1 month after adult thymectomy. The proportions of insulin-, glucagon-, and somatostatin-immunoreactive cells in the pancreas were estimated on paraffin sections using the unlabelled peroxidase-antiperoxidase method. Relative islet volume, islet size and number were determined on hematoxylin and eosin stained sections. A moderate increase of the islet volume on account of size was found in the pancreas of the thymectomized rats. The proportion of insulin-immunoreactive cells was also elevated. Ultrastructural studies showed a rich supply of secretory granules in most beta-cells. Mixed beta-endocrine-acinar cells were often observed. Mitotic figures were found in single beta-cells. The blood glucose level was in the normal range. The findings suggest a moderate stimulation of beta-cell secretory activity after thymectomy which is not associated with elevated blood glucose levels.

Stress-induced changes in the cyclic nucleotide concentrations and phosphorylase activity in the myocardium.

Restraint stress was produced by immobilizing rats in supine position for 6, 12 and 24h. Control rats were deprived of food and water for the same time intervals. Concentrations of cyclic AMP and cyclic GMP and activity of glycogen phosphorylase were studied in the ventricle myocardium of the animals. The cAMP concentrations in the myocardium of immobilized rats were significantly lower after 6 and 12h, but were higher after 24 h compared with control values. The cyclic GMP concentrations showed the same tendency though the differences were not significant. The concentrations of cAMP and cGMP in both restrained and control rats increased in the 12-hour experiment but decreased in the 24-hour experiment as compared to the 6 h values. Phosphorylase "a" and total phosphorylase activities were higher after 12-hour immobilization, but were lower after 24-hour restraint compared with control group. In the 6-hour experiment there were no differences between restrained and control rat. The percentage of phosphorylase "a" of the total activity was equal in immobilized and control animals. time related changes were also observed in the phosphorylase activity. The present results suggest that cyclic nucleotides and glycogen phosphorylase may improve myocardial metabolism by diminution of energy consumption and activation of glycogenolysis under trees conditions.

Comparative studies on catecholamine content and glycogen phosphorylase activity in the myocardium of spontaneously hypertensive and normotensive rats.

Myocardial noradrenaline (NA) and adrenaline (A) concentrations as well as phosphorylase (PHOS) activity in spontaneously hypertensive (SHR) and normotensive Wistar (NWR) rats 1.5, 3, 6, 12 and 18 months of age were assayed. Myocardial hypertrophy as determined by the heart/body weight ratio in 1.5 month old SHR preceded the onset of hypertension. The arterial blood pressure (ABP) of SHR was significantly elevated from month 3 onward attaining a maximum level at month 12. The concentrations of A and NA, and activity of PHOS "a" in SHR were lower than in NWR between months 3 and 12. The differences were marked in SHR 3 months of age, and corresponded to the ABP changes. An age-dependent decrease in A, NA and PHOS "a" in SHR was observed. The data suggest a role of catecholamines in the development of cardiac hypertrophy via regulation of metabolism.

[Changes in the activity of glycogen phosphorylase in the rat myocardium after immobilization stress]. / Promeni v aktivnostta na glikogenfosforilazata v miokarda na plukhove sled imobilizatsionen stres.

Immobilization stress with duration of 6, 12 and 24 hours was induced in rats of Wistar strain. The rats of the control group were without food and water for the same periods of time. The active form a of glycogen phosphorylase, total enzymic activity a-b and the percentage of the active form of the total enzymic activity in the myocardium of the left ventricle, right ventricle and intraventricular septum were determined. There were no statistically significant differences in the activity of phosphorylase a and in the total enzymic activity between the control and experimental animals on the sixth hour since the onset of the study. The activity of both forms of the enzyme in the right ventricle and septum was higher in comparison with that of the control animals after 12 hours of immobilization. The enzymic activity was reduced in comparison with that of the control animals after 24 hours of immobilization. It could be assumed that metabolic adaptive mechanism of the cardiac muscle improve conditions for formation of energy from carbohydrate sources.

Ischaemia-induced changes in the phosphorylase activity in different parts of the cardiac conduction system.

The phosphorylase specific activity was lowered in total ischaemia in all examined parts of the myocardium and the conduction system of the heart. Sixty-minute ischaemia had a considerable effect on glycogen degradation in right bundle branch and in the working myocardium, however, its glycogenolytic effect on the AV-node and penetrating bundle of His was insignificant. Phosphorylase "a" evaluated as a percentage of the total phosphorylase activity decreased in the working myocardium and increased in the AV-node during ischaemia. The data obtained support the hypothesis according to which conductive tissue is more resistant to ischaemia than the working myocardium. The results serve evidence that the right bundle branch is more susceptible to metabolic damage caused by ischaemia than the AV-node and penetrating bundle of His.

[Effect of thymectomy on the functional activity of the thyroid gland in rats]. / Vliianie na timektomiiata vurkhu funktsionalnata aktivnost na shchitovidnata zhleza na plukhove.

The authors examined the functional state of the thyroid gland of rats after thymectomy. The dynamics of incorporation of radioactivity I131 in the gland was examined on the 2,20 and 90th day after the operation. There was increased incorporation of the radioisotope in the thyroid giant at the early stages of the experimental period. A reduced incorporation and delayed excretion was observed in the distant periods. Changes in the activity of the thyroid gland were accepted as a manifestation of the existing functional link between the thymus and thyroid gland.

[Participation of cyclic-3',5'-adenosine monophosphate in the pathogenesis of myocardial hypertrophy in experimental hypertension]. / Uchastie na tsiklichniia 3', 5', adenozinomonofosfat v patogenezata na miokardnata khipertrofiia pri eksperimentalnata khipertoniia.

The authors examined the concentration of cAMP in the myocardium of rats with experimental hypertension during various periods after modeling of the process. The changes in the values of cyclic nucleotide corresponded to the dynamics of the development of the arterial hypertension. There was na increase of the level of cAMP in the myocardium on the third day after modeling of hypertension, accompanying the initial elevation of the arterial pressure. The maximal values of cAMP were established on the 30th day, which corresponded to the maximal development of hypertension. Cyclic 3,5-adenomonophosphate began to diminish parallel to the lowering of the arterial pressure during the chronic phase 90th day. The obtained results give a possibility to discuss the participation of cAMP in the pathogenesis of myocardial hypertension, occurring in experimental hypertension.

[Changes in renal enzyme activity in rats with experimental hypertension]. / Promeni v enzimnata aktivnost na bubretsite pri eksperimentalna khipertoniia u plukhove

The study was carried out on rats of the Wistar strain with experiments hypertension by the method of Selye, modified by Kolarova. These authors examined the activity of the enzymes of protein metabolism (GOT, GPT, AP), of glycolysis (ALD, LDH, alpha-HBDH) and of the citric cycle (MDH) in the left and right kidney at various intervals after modeling the process (3th, 15th, 30th and 90th day). The activity of the enzymes of the glycolytic chain and the cycle of Krebs in the left kidney was lowered at all stages of the experiment. Transaminase activity diminished progressively. Such a dynamics revealed the activity of adenosine phosphate as well. The activity of all examined enzymes of the right kidney showed phase changes-after initial elevation on the third day there was a lowering at the later stages of the experiment. The altered activity off the left kidney was connected with the disturbed vascularization with subsequent metabolic changes. The changes in the enzymic activity in the right kidney were assumed as a consequence of the occurred adaptive hyperfunction.