Effect of iron chloride (III) on hematological status of the Planorbarius corneus (Mollusca: Gastropoda: Bulinidae) in normal snails and during infection with trematode parthenites

The effect of three ferric chloride concentrations (100, 200, 300 mg/l) on the acid-alkaline balance of haemolymph and haemoglobin content in Planorbarius corneus under normal conditions and in the case of infection with parthenites and larvae of Echinoparichium aconiatum was examined. In the medium with an effective concentration of ferric chloride, all snail specimens proved to have acidified haemolymph, by 40-50% in infected samples and 80-85% in uninfected ones. Statistically reliable differences in the haemoglobin content in the haemolymph of infected and uninfected specimens between the control and test media were absent, that proves a weak toxic effect of ferric ions on P. corneus.     

A new species of Tigriopus (Copepoda, Harpacticoida, Harpacticidae) from Thailand with the description of its naupliar development

Both genders of Tigriopus thailandensis sp. nov. are described from a laboratory stock raised from individuals collected from the seaweed Enteromorpha clathrata in Thailand (Bangsaen Beach, Chonburi Province). Tigriopus thailandensis sp. nov. shares with its closest relative T. japonicus Mori, 1932 two setae on the third exopodal segment of leg 4 while other congeners bear 3 inner setae. However, allobasis and exopod of antenna in both genders are much more slender and elongate than in T. japonicus. All six naupliar stages of T. thailandensis are described from the offspring of isolated females. In comparison with nauplii of T. japonicus, T. thailandensis nauplii are characterized by the following: a smaller body size throughout the naupliar phase; first antennular segment without seta, second antennular segment with only one small seta plus two longer setae; third antennular segment with additional spinules from naupliar stage II onwards; antenna bears three small spinules on the terminal exopodal segment; one additional seta on the anterior surface of the antennary basis, tubular endopod of antenna with one tiny seta midlength at naupliar stage III that increases in size; mandibular basis with several spinules on anterior surface; mandibular coxa with one spinulose seta that is smooth in T. japonicus.     

Vibration-Induced Frontal Postural Reactions in Humans Standing on Unstable Supports of Various Types

The authors studied the influence of the direction of support stability the vibration-induced frontal postural reactions of healthy humans during unilateral vibration of three lateral muscles, namely, the long peroneal muscle, tensor muscle of fascia lata, and abdominal external oblique muscle. The subjects stood on a movable blotter- shaped support. Its base was cylindrical or spheric; its height was 24 cm, and its base radius was 40 cm. The platform turn angle and sagittal and frontal horizontal shift of the upper part of the subjects' bodies were recorded. Reacting to vibrations, the subjects tilted their bodies contralaterally to the vibrated muscle, irrespective of the support type. These reactions were strongest when the subjects stood on a stable support and were weakest when the support was unstable. The reaction values were also influenced by the distance between the vibrated muscle and general center of gravity of the body. As a rule, all other things being equal, vibration-induced reaction strengthened when the stimulated muscle was closer to the center of gravity. The authors concluded that vibration-induced frontal reactions of a standing human depend on the support properties and reflect the features of the participation of the lateral muscles in the standing posture regulation. The information received from the lateral muscular receptors by the control system may be used in different manners, depending on the internal body–support interaction model formed by the CNS.     

DNA synthesis in connective tissue elements of regenerating skin under the influence of thyrocalcitonin and hypoxia

The influence of TCT on the proliferation activity of the connective tissue elements of the regenerating skin in normal and lowered partial oxygen tension was studied by means of H3-thymidin autoradiography. Continuous saturation of the organism with exogenous TCT is characterized by an increase in the count of cells during the S-period of mitotic cycle, the DNA synthesis intensification, and a considerable decrease in the number of silver grains over the nuclei in the course of the 24-hour observation period; this can testify to the acceleration of the cell passage of mitotic cycle stages in normal and low partial oxygen tension in hypoxia.