Consumption of aquatic subsidies by soil invertebrates in coastal ecosystems

Routes of aquatic allochthonous inputs (aquatic subsidies) to detrital food webs are studied, as is the effect of aquatic subsidies on the functional and taxonomic structure of soil invertebrate communities in coastal ecosystems. The study took place in the coastal zone of an oxbow lake of the Pra River in the Oka Reserve. The results indicate a strong dependence of soil animals in the coastal habitats on aquatic subsidies. Isotopic analysis shows that aquatic resources enter soil food webs not only via predators feeding on flying insects or aquatic prey, but also via saprophages decomposing organic debris of aquatic origin. The contribution of aquatic subsidies to the energy balance of soil invertebrates decreases rapidly with increasing distance from the lake. The fraction of aquatic carbon in tissues of collembolans and saprophages is negligible already a few meters from the water edge. The dependence of predatory invertebrates on aquatic resources can be traced at somewhat greater distance (tens of meters).     

Spinoreticular neurons that receive group III input are inhibited by MLR stimulation.

In decerebrate paralyzed cats, we examined the responses of 18 spinoreticular neurons to electrical stimulation of the mesencephalic locomotor region. The activity of each of the spinoreticular neurons was recorded extracellularly from laminae IV through VI of the L(7) and S(1) spinal cord. In addition, each of the 18 spinoreticular neurons received group III afferent input from the tibial nerve. Spinoreticular projections were established for each of 18 neurons by antidromic invasion of the ventro lateral medulla at the P11 though P14 levels. The onset latencies and current thresholds for antidromic invasion from the ventro lateral medulla averaged 15.0 +/- 3.8 ms and 117 +/- 11 microA, respectively. Electrical stimulation of the mesencephalic locomotor region attenuated the spontaneous activity or the responses of each of the spinoreticular neurons to tibial nerve stimulation at currents that recruited group III afferents. Our data support the notion that thin-fiber muscle afferent input to the ventrolateral medulla is gated by a central command to exercise.     

Ultrastructural and functional changes in the myocardium and coronary vessels after massive blood loss

The ultrastructure of cardiomyocytes and circulatory bed has been compared to transmembrane cAMP-dependent Ca2+ transport in experiments on the hearts of 14 dogs immediately after massive blood loss. The results an hour after non-compensatory hemorrhage have shown extra- and intracellular myocardial edema, central destruction of sarcomers, steep increase in the volume of agranular sarcomplasmic reticulum and T-system, different degree of damage of other organoids, and also disturbances in the ultrastructure of venous capillary and postcapillary section. The biochemical techniques used have shown a decrease in Ca2+ transporting ability of sarcolemma due to its AMP-dependent regulation of cardiomyocytes. Excessive Ca2+ storage in cytosole promoted the appearance of "constriction bands" in myofibrils.     

The effect of Mg 2+ ions on the properties of various strains of Yersinia pestis

The strains of Yersinia pestis that restrict their growth on the media deficient for Mg2+ ions at 37 degrees C have been found. The bacterial cell lysis is registered under these conditions. The effect of Yersinia pestis own plasmids on the level of growth restriction in the absence of Mg2+ ions has been studied. The phenomenon is not connected with the presence of the plasmid determining Ca2(+)-dependence. The presence of 6Md plasmid coding for pesticinogenicity increased the frequency of colony formation, while the heavy plasmid determining the production of "mouse" toxin favoured the increase in growth restriction on Mg2(+)-less media. The clones growing under the latter conditions acquire the rearrangements in the DNA of the plasmid coding for the "mouse" toxin.     

Effects of ovariectomy on the composition of fatty acids of phospholipids in Java macaques with cholestasis

Bilateral ovariectomy carried out in Java macaques with simultaneous dosed ligation of common bile duct distally to duodenum in order to induce acalculous hepato-cholecystitis, does not alter the lithogenic index of the bile. Phospholipids present in enterohepatic organs and tissues (hepatocytes, enterocytes, chyme, blood and bile) of gonadectomized animals with hepato-cholecystitis acquire a specific fatty acid pattern which is characterized by prevailing palmitic, stearic and oleic acids, unaffected level of arachidonic acid and traces of essential linoleic acid.     

Effect of immobilization stress on the gonadotropic function of the hypophysis in male hamadryas baboons (Papio hamadryas)

The plasma levels of luteinizing hormone (LH) and testosterone were studied in intact and castrated male baboons exposed to 2- and 10-hour periods of immobilization. Presented data have shown that immobilization stress induced a marked decrease in LH concentration both in intact and castrated monkeys. Changes in LH concentration positively correlated with plasma levels of testosterone only during the experimental procedures. During three days after immobilization there was a sharp dissociation in the dynamics of testosterone levels remained low and LH returned to normal values. We can suggest that it is not absolute LH level that is responsible for the changes in testosterone secretion during the immobilization stress.     

Cytotoxic Effects of the Selective Ligands of Membrane Progesterone Receptors in Human Pancreatic Adenocarcinoma Cells BxPC3

Biochemistry (Moscow) - Progesterone and its synthetic analogues act on cells through different types of receptors, affecting proliferation and apoptosis. These compounds exert their effect through...     

Inner Nuclear Layer Thickening Is Inversley Proportional to Retinal Ganglion Cell Loss in Optic Neuritis

Aim

To examine the relationship between retinal ganglion cell loss and changes in the inner nuclear layer (INL) in optic neuritis (ON).

Methods

36 multiple sclerosis (MS) patients with a history of ON and 36 age and sex-matched controls underwent Optical Coherence Tomography. The paramacular retinal nerve fiber layer (RNFL), combined ganglion cell and inner plexiform layers (GCL/IPL) and inner nuclear layer (INL) thickness were measured at 36 points around the fovea. To remove inter-subject variability, the difference in thickness of each layer between the ON and fellow eye of each patient was calculated. A topographic analysis was conducted.

Results

The INL of the ON patients was thicker than the controls (42.9µm versus 39.6µm, p=0.002). ON patients also had a thinner RNFL (27.8µm versus 32.2µm, p<0.001) and GCL/IPL (69.3µm versus 98.1µm, p<0.001). Among the controls, there was no correlation between RNFL and GCL/IPL as well as RNFL and INL, but a positive correlation was seen between GCL/IPL and INL (r=0.65, p<0.001). In the ON group, there was a positive correlation between RNFL and GCL/IPL (r=0.80, p<0.001) but a negative correlation between RNFL and INL (r=-0.61, p<0.001) as well as GCL/IPL and INL (r=-0.44, p=0.007). The negative correlation between GCL/IPL and INL strengthened in the ON group when inter-subject variability was removed (r=-0.75, p<0.001). Microcysts within the INL were present in 5 ON patients, mainly in the superior and infero-nasal paramacular regions. While patients with microcysts lay at the far end of the correlation curve between GCL/IPL and INL (i.e. larger INL and smaller GCL/IPL compared to other patients), their exclusion did not affect the correlation (r= -0.76, p<0.001).

Conclusions

INL enlargement in MS-related ON is associated with the severity of GCL loss. This is a continuous relationship and patients with INL microcysts may represent the extreme end of the scale.