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The aim of the research was to examine the influence of orchidectomy on the elasticity and wall structure of the abdominal aorta in male rats and to check whether camelina oil treatment has an effect on aorta wall characteristics in orchidectomized rats. Forty 2-month-old male Wistar rats were used in the experiment: 10 animals underwent a sham testis repositioning operation (SHO) and 30 rats were orchidectomized (ORX). After the convalescence period, the SHO and ORX1 rats were given physiological saline intragastrically for 8 weeks; simultaneously, the other rats received camelina oil at the dose of 5 g/kg/b.w. (ORX2) or 9 g/kg/b.w. (ORX3) once a day. At the end of experiment, the animals were euthanized and fragments of the aorta were sampled for elasticity measurement and for histomorphometric and immunohistochemistry analysis. Orchidectomy caused a significant increase in the thickness of the total wall and its particular layers, mean intensity of elastin fluorescence in the tunica intima-media, and the volume of collagen I in tunica adventitia of the abdominal aorta in comparison to the other groups. The mean intensity of collagen I fluorescence in the tunica adventitia and tunica intima-media was significantly lower in the aorta of the orchidectomized rats. The values of the histomorphometric parameters of animals receiving camelina oil were lower than in the ORX1 group and higher than in the SHO rats. The values of the other parameters analyzed after the camelina oil treatment were similar to those in the SHO rats. In conclusion, our study showed that orchidectomy induced changes in the abdominal aorta wall characteristic for aging. Supplementation with camelina oil prevents negative consequences in the vessel wall structure in males with impaired endocrine function.

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The subject of the experimental research supported with numerical simulations presented in this paper is an analog electrical circuit representing the ring of unidirectionally coupled single-well Duffing oscillators. The research is concentrated on the existence of the stable three-frequency quasiperiodic attractor in this system. It is shown that such solution can be robustly stable in a wide range of parameters of the system under consideration in spite of a parameter mismatch which is unavoidable during experiment.

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We describe general characteristics of the Hodgkin-Huxley neuron's response to a periodic train of short current pulses with Gaussian noise. The deterministic neuron is bistable for antiresonant frequencies. When the stimuli arrive at the resonant frequency the firing rate is a continuous function of the current amplitude I(0) and scales as (I(0)-I(th))(1/2), characteristic of a saddle-node bifurcation at the threshold I(th). Intervals of continuous irregular response alternate with integer mode-locked regions with bistable excitation edge. There is an even-all multimodal transition between the 2 : 1 and 3 : 1 states in the vicinity of the main resonance, which is analogous to the odd-all transition discovered earlier in the high-frequency regime. For I(0)

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The experimental data of Takahashi [Physica D 43, 318 (1990)], on the response of squid giant axons stimulated by periodic sequence of short current pulses is interpreted within the Hodgkin-Huxley model. The minimum of the firing rate as a function of the stimulus amplitude I0 in the high-frequency regime is due to the multimodal transition. Below this singular point only odd multiples of the driving period remain and the system is sensitive to noise. The coefficient of variation has a maximum and the firing rate has a minimum as a function of the noise intensity, which is an indication of the stochastic coherence antiresonance. The model calculations reproduce the frequency of occurrence of the most common modes in the vicinity of the transition. A linear relation of output frequency vs I0 above the transition is also confirmed.

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We study the response of a Hodgkin-Huxley neuron stimulated by a periodic sequence of conductance pulses arriving through the synapse in the high-frequency regime. In addition to the usual excitation threshold there is a smooth crossover from the firing to the silent regime for increasing pulse amplitude gsyn. The amplitude of the voltage spikes decreases approximately linearly with gsyn. In some regions of parameter space the response is irregular, probably chaotic. In the chaotic regime between the mode-locked regions 3:1 and 2:1 near the lower excitation threshold, the output interspike interval histogram (ISIH) undergoes a sharp transition. If the driving period is below the critical value, TT* even multiples of Ti also appear in the histogram, starting from the largest values. Near T* the ISIH scales logarithmically on both sides of the transition. The coefficient of variation of ISIH has a cusp singularity at T*. The average response period has a maximum slightly above T*. Near the excitation threshold in the chaotic regime the average firing rate rises sublinearly from frequencies of order 1 Hz.

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AIM: The aim of the investigation was to assess the effects of the resistive inspiratory muscle training (IMT) in elite male rowers. METHODS: Fifteen senior rowers were assayed for the maximal inspiratory mouth pressure (PImax) and maximal oxygen uptake (VO2max), and then randomized into two groups: the control and the experimental group. The latter athletes, in addition to basic training, were subjected to the 11-week IMT consisting of a series of 30 inspiratory efforts performed twice a day. Athletes from the control group did only the basic training. RESULTS: No significant relations were detected between the initial values of PImax and the VO2max value. After 6 weeks of IMT the PImax values increased by 20+/-10% (P < 0.05), whereas the final improvement (after 11 weeks of IMT) equaled to 34+/-19% (P < 0.05). In the control group, the final increase equaled to 4+/-9% and was statistically insignificant. Compared to the values obtained at the end of IMT, 14 weeks after cessation of the training PImax insignificantly decreased in the experimental group by 10+/-9%, but the measured values were still significantly higher than before the commencement of IMT. CONCLUSION: The data obtained corroborate the observations that in well-trained athletes the introduction of the principle of incremental inspiratory resistance allows to improve methodically the inspiratory muscles' strength. Once the essential period of IMT has been completed, the training volume should be reduced in order to secure the attained level of the inspiratory muscles' strength.

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PURPOSE: To present a case of choroidal neovascularization associated with sympathetic ophthalmia successfully treated with photocoagulation. DESIGN: Interventional case report. METHODS: A 41-year-old man with a history of penetrating injury right eye, as well as sympathetic ophthalmia left eye, developed a classic choroidal neovascular membrane that threatened the center of the fovea. RESULTS: The patient was treated with argon laser photocoagulation. He has maintained stable visual acuity without evidence of recurrence of the membrane with 4 years' follow-up. CONCLUSION: Thermal laser should be considered as a treatment option in cases of choroidal neovascularization associated with sympathetic ophthalmia.

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PURPOSE: To report unusual fundus findings in two cases of melanoma-associated retinopathy. METHODS: Observational case reports. The histories of two patients with melanoma-associated retinopathy were reviewed. Sera from both patients were examined for antibodies against retinal bipolar cells. Immunofluorescence was performed on cryostat sections of unfixed normal human retinas. Sera and IgG from both patients were tested against a known melanoma-associated retinopathy patient as well as a control subject. RESULTS: Our patients had metastatic, cutaneous melanoma and a clinical syndrome consistent with melanoma-associated retinopathy. Both patients had serum antibodies that were reactive against retinal bipolar cells. They had unusual fundus changes not previously described in association with melanoma-associated retinopathy. One patient also developed vitiligo. CONCLUSION: Patients with metastatic cutaneous melanoma and melanoma-associated retinopathy may present unusual fundus lesions that may be caused by autoimmunity which is part of the clinical picture of melanoma-associated retinopathy or metastatic melanoma.

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Twelve girls who trained in rowing were examined twice a year for 4 years. Their initial age was 11.7 +/- (SD) 0.2 yrs. Control groups consisted of 13 girls age 11.5 +/- 0.3 yrs and 18 girls age 14.4 +/- 0.3 yrs examined simultaneously with trained girls in the first and last year of the study, respectively. The examination involved basic anthropometry, estimation of sexual maturation (Tanner scale), 2-day food records, measurements of resting metabolic rate, energy expenditure following glucose ingestion (50 g), and determinations of blood glucose and plasma insulin concentrations prior to and 2 hrs after glucose load. Body mass, height, and fat content were slightly greater in trained girls. None of the subjects reported disturbances in menstrual function, and the age of menarche was similar for all. Both trained and untrained girls reported similar daily energy intake closer to the lower limit or slightly below the estimates of energy requirements for adolescents. Resting metabolic rate calculated per kg of total body mass or lean body mass was lower in trained girls, while the thermogenic effect of glucose was greater. Plasma insulin concentrations measured 2 hrs after glucose ingestion were lower in trained girls. The results suggest that in circumpubertal girls, increased physical activity leads to energy conservation at rest in postabsorptive state and a tendency toward enhancement of food-induced thermogenesis.

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The new immunosuppressive and anti-inflammatory agents have been searched in a group of the synthetic L-cysteine and 3-acetyl-thiazolidine-4-carboxylic acid derivatives. Synthesis of 17 compounds is reported.

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