Electrophysiology of bull spermatozoa : Correlations with motility

The bioelectric characterization of bull spermatozoa was based on the establishment of a standard, for comparison with cells subjected to manipulation of the ionic environment. In addition to potassium and sodium, chloride concentration was also found to have an effect on bull spermatozoa membrane potential and motility. The chloride effect on potential was similar in magnitude to that of sodium but smaller than that of potassium. Potential difference in potassium, sodium and chloride supplemented media was related to the amplitude of the flagellar wave.     

Satellite tracking a wide-ranging endangered vulture species to target conservation actions in the Middle East and East Africa

Vultures comprise the most endangered avian foraging guild (obligate scavengers) and their loss from ecosystems can trigger trophic cascades, mesopredator release, and human rabies epidemics, indicating their keystone species status. Vultures’ extremely large home ranges, which often cross international borders of countries that have differing laws and capacity for wildlife conservation, makes conserving them challenging. However, satellite-tracking data can be used to identify habitat preferences and critical sites to target conservation actions. We tracked 16 Egyptian Vultures, Neophron percnopterus, in the Middle East and East Africa. We used dynamic Brownian bridge movement models to calculate home ranges and core-use areas, and we analyzed habitat use in a resource selection framework. Combined summer and winter ranges (99% utilization distributions) of all birds covered 209,800 and 274,300 km², respectively. However, the core-use areas (50% utilization distributions) in the summer and winter ranges, accounted for only 0.4–1.1% of this area (900 and 3100 km², respectively). These core-use areas are where the home ranges of multiple individuals overlapped and/or where individuals spent a lot of time, such as feeding and roosting sites, and are places where conservation actions could focus. Resource selection models predicted Egyptian Vulture occurrence throughout little-studied parts of the species’ range in the Middle East and East Africa, and revealed strong selection for proximity to highways, power distribution lines, and towns. While providing roosts (e.g. power pylons) and food (e.g. garbage dumps), anthropogenic features may also function as ecological traps by increasing exposure to electrocution and dietary toxins.     

Breeding site selection by bearded vulture (Gypaetus barbatus) and Eurasian griffon (Gyps fulvus) in the Caucasus

Occupied and unoccupied sites of bearded vulture Gypaetus barbatus and Eurasian griffon Gyps fulvus were located in the Caucasus (mainly Georgia). Habitat variables related to nest-site characteristics, climate, terrain, human disturbance and food availability were used to construct predictive models of vulture breeding site selection by using a geographic information system (GIS), logistic regression and Bayesian statistical inference. The probability of bearded vulture occupancy of a cliff ledge that was safe from climatic adversity, human disturbance and predation was positively correlated with the following variables measured within a 20-km radius of the ledge: mean elevation, mean slope, the percentage of open areas, mean distance to roads, number of globally threatened wild goats Capra cylindricornis, C. caucasica and C. aegargus , and annual biomass of dead livestock. The probability of such a cliff ledge being occupied by Eurasian griffon was negatively correlated with annual rainfall at the ledge and positively correlated with the percentage of open areas and annual biomass of dead livestock within 20 km of the ledge. Provided that GIS coverage of the habitat variables is available, these models can be of help in various areas of the Caucasus and elsewhere to predict possible nest occurrence areas, and highlight sites where vultures may occur in the future if the population grows because of conservation or other activities.     

Plant virus infection development as affected by heavy metal stress

The work was focused on the investigation of possible dependencies between the development of viral infection in plants and the presence of high heavy metal concentrations in soil. Field experiments have been conducted in order to study the development of systemic tobacco mosaic virus (TMV) infection in Lycopersicon esculentum L. cv. Miliana plants under effect of separate salts of heavy metals Cu, Zn and Pb deposited in soil. As it is shown, simultaneous effect of viral infection and heavy metals in tenfold maximum permissible concentration leads to decrease of total chlorophyll content in experiment plants mainly due to the degradation of chlorophyll a. The reduction of chlorophyll concentration under the combined influence of both stress factors was more serious comparing to the separate effect of every single factor. Plants' treatment with toxic concentrations of lead and zinc leaded to slight delay in the development of systemic TMV infection together with more than twofold increase of virus content in plants that may be an evidence of synergism between these heavy metal's and virus' effects. Contrary, copper although decreased total chlorophyll content but showed protective properties and significantly reduced amount of virus in plants.     

Predictors of success in hypertensives treated with biofeedback-assisted relaxation

This paper describes differences in response in seventeen patients with essential hypertension who participated in a treatment program consisting of electromyograph biofeedback assisted relaxation training. Responders were found to have higher treatment values of urinary and plasma cortisol, Trait Anxiety and forehead muscle tension compared to treatment failures. Responders also sustained greater decreases in plasma, and urinary cortisol after treatment. These data are discussed in light of the ability to predict which hypertensive patients may be most benefitted by a relaxation based treatment.We would like to thank Dr. Charles Spielberger for his permission to use the State-Trait Anxiety Inventory. We thank Michael Robinson for assistance with statistical analysis.     

Racial and gender effects on the relaxation response: Implications for the development of hypertension

This study was designed to explore the effect of race and gender on the forehead muscle tension and finger temperature response to biofeedback-assisted relaxation training in individuals with normal blood pressure. Forty-five subjects—18 Black and 27 White, 25 males and 20 females—participated in eight sessions of autogenic relaxation training and thermal biofeedback. Multivariate analysis of variance of the variables measured at baseline (systolic BP, diastolic BP, sodium excretion, anxiety) was significant for gender. Univariate analysis showed males different from females in DBP, Na⁺ excretion, and trait anxiety. Pretest values of muscle tension were similar by gender, but pretest temperatures were lower in males than females. Repeated measures ANOVA for muscle tension showed a significant effect of period. For temperature, a significant effect of period, gender, and gender × period was observed. Males increased temperature more than females. There was no effect of history of hypertension on the relaxation response. Multiple regression performed on change in muscle tension and change in temperature showed that pretest muscle tension predicted change in muscle tension. Four variables contributed to the variance in change in temperature: pretest temperature, sodium excretion, and state and trait anxiety.     

A provisional model to predict blood pressure response to biofeedback-assisted relaxation

Blood pressure (BP) response to biofeedback-assisted relaxation is not uniform among hypertensive individuals. The purpose of this exploratory study was to determine if selected psychophysiological variables could be used to identify individuals able to lower blood pressure using biofeedback-assisted relaxation. Responders were defined using a preset criterion of 5 mm Hg or greater decrease in mean arterial pressure. A logistic regression model derived from five variables (heart rate, finger temperature, forehead muscle tension, plasma renin response to furosemide, and mean arterial pressure response to furosemide) provided significant predictive power for BP response, exhibiting a sensitivity of 84.6% and a specificity of 80.0%. With future validation, the proposed model may provide useful information to identify patients likely to benefit from biofeedback-assisted relaxation.     

Sustained effects of biofeedback-assisted relaxation therapy in essential hypertension.

The usefulness of biofeedback-assisted relaxation as an adjunct or substitute for pharmacotherapy in essential hypertension can be enhanced if the effects are shown to persist after formal treatment has ended. Patients with essential hypertension successfully treated with biofeedback-assisted relaxation were recalled for follow-up yearly after the termination of treatment. Twenty-six of 40 patients met the BP criterion for success. At one-, two-, and three-year follow-up, 31%, 38%, and 27% of the successful completers continued to meet the criterion for success. The pretreatment-posttreatment decreases in BP were accompanied by decreases in forehead muscle tension and urinary cortisol. Forehead muscle tension, urinary cortisol, and anxiety levels were significantly lower than pretreatment one year after the end of treatment. Self-report data were used to assess continued relaxation practice. No relationship was found between practice and any other dependent measure. It appears that some patients trained in biofeedback-assisted relaxation can maintain lowered blood pressure, muscle tension, anxiety, and cortisol levels over the long term; however, the role of relaxation practice in maintaining these lowered levels remains unclear.     

Effects of group relaxation training and thermal biofeedback on blood pressure and related physiological and psychological variables in essential hypertension

One hundred and one patients, 70 experimental and 31 controls, with a diagnosis of essential hypertension, were examined for the effects of group relaxation training and thermal biofeedback on blood pressure and on other psychophysiologic measures: heart rate, forehead muscle tension, finger temperature, depression, anxiety, plasma aldosterone, plasma renin activity, and plasma and urinary cortisol. Eighty percent of the participants were medicated. Treatment yielded a short-term success rate, defined as a decrease in mean arterial pressure of 5 mm Hg, of 49% in the experimental group. Other significant short-term changes included a reduction of forehead muscle tension, state anxiety, plasma aldosterone, and increased finger temperature. Follow-up measurements were made approximately 10 months after treatment in 36 patients, 51% of the treatment completers. Twenty of the 36 were short-term treatment failures, while 16 were treatment succeeders. Thirty-seven percent of the short-term succeeders continued to meet blood pressure criterion at follow-up. In short-term succeeders, continued practice of relaxation may influence long-term maintenance of decreased blood pressure. It is suggested that group relaxation training can be beneficial for short-term and long-term adjunctive treatment of essential hypertension in selected individuals.I greatly appreciate the assistance of Minda Sogocio, Judy Stewart, and Kay Gerstenmaier from the Toledo Health Department, and Ilona Jurek, Carrie Wakai, and Robert Spain from the Medical College of Ohio at Toledo. This research was supported by a grant to A. McGrady through the Hypertension Control Program of the City of Toledo Health Department, from the Ohio Department of Health.     

Effects of Wellness Programs in Family Medicine

The objective of this research was to determine the effects of wellness programs on quality of life and utilization in an academic family medicine practice in two small controlled studies. One offered stress management and problem solving; the second offered a broader wellness intervention. Outcome measures consisted of scores on the Beck Anxiety Inventory, Hamilton Depression Inventory, CES-D (depression), Health Related Quality of Life, SF-12, and the number of office visits in 6 months. Subjects were randomly assigned to intervention or control groups. Statistical analysis compared pre-test and post-test values of the dependent variables between groups. In study one, where the focus was on relaxation, significant differences between groups were observed in anxiety at post-test (p < .03); the intervention group had lower anxiety levels. In study two which had a more general focus, significant group differences were found in days of poor mental health and number of days of depressed mood; the intervention group had fewer days of poor mental health (p < .05) and depression (p < .05) at post-test. No differences were found in utilization in either study. Based on the results of this research, short term wellness programs can be implemented in family practice and are effective in improving quality of life, but not in deceasing utilization in family practice patients. Matching the design of the program to specific patient needs may increase retention and effectiveness.