Medicine and medical sciences in Africa.

The year 2014 is an important year because it will mark the 25th Anniversary of the founding of the African Association of Physiological Sciences (AAPS) and initial talks to launch the International Society for Pathophysiology (ISP). Both these organizations had a foothold in Finland and both occurred during the IUPS Centennial Celebration Congress in 1989. The congress was hosted by the Finnish Physiological Society in Helsinki, Finland in July 1989. For both organizations, Prof OsmoHänninen was instrumental in the launching and inauguration of AAPS and also to initiate the creation of ISP. In order to celebrate the 25th Anniversaries of both organizations it was decided to hold the ISP2014 congress on the African soil. Hence in 2004, at the 4th international congress of AAPS held in Morocco, Wail Benjeloun.the then secretary general of AAPS, submitted successfully a bid to host ISP2014 in Morocco. Following the inauguration of AAPS in Helsinki, the 1st Congress of AAPS was held in Nairobi, Kenya in 1992 where the Constitution of AAPS was drawn up. The Constitution was adopted at the 2nd congress of AAPS in Durban, South Africa in 1997. Following this congress, the next congress, as scheduled, was held in Pretoria, South Africa in 2000. The last congress (6th) of AAPS was held on 1-5 September 2012 in Ismailia, Egypt. This was an historical congress because of many reasons and amongst these was the appointment of Anthony B. Ebeigbe, Department of Physiology, University of Benin, Nigeria as its first Editor-in-Chief of its official journal, the Journal of the African association of Physiological Sciences (JAAPS). He successfully published the first issue in June 2013, as mandated in Ismailia. The World's medicine has its initial root in Africa and in fact it was in Memphis, Egypt as early as 2700 BC. During the Ptulomaic period the seat of medicine was in Alexandria, Egypt and Medical knowledge then spread to the Greeks 330 BC. Many western medical scientists acknowledge learning medicine and anatomy form the Egyptian experts. The University of Al Karaouine, in Fez, Morocco, Africa is considered the oldest continuously operating university in the world and has been a center of learning for more than 1,000 years. Medicine in Africa has been acknowledged by many authoritarians to be well developed, long before its development in Greece and other European Countries. Almost every African country has medical and medical sciences societies and associations. According the WHO, African journals online (AJOL) as the worlds largest collection of peer-reviewed journals. It is also believed that Africa will play a major role in Sciences in the future, and in fact one of the Worlds leading palaeo-anthropologist was a South African.

Coenzyme Q(10) and selenium in statin-associated myopathy treatment.

The objective of this study was to evaluate the possible benefits of coenzyme Q10 and selenium supplementation administered to patients with statin-associated myopathy (SAM). Sixty eligible patients entered the pilot study. Laboratory examination (CoQ10, selenium, creatin kinase) and intensity of SAM (visual scale) were performed at baseline, after 1 month, and at the end of study at month 3. Plasma levels of CoQ10 increased from 0.81 ± 0.39 to 3.31 ± 1.72 µmol/L in the active group of patients treated by CoQ10, compared with the placebo (p = 0.001). Also, the symptoms of SAM significantly improved in the active group (p < 0.001): the intensity of muscle pain decreased from 6.7 ± 1.72 to 3.2 ± 2.1 (p < 0.01, -53.4 ± 28.2%); muscle weakness decreased from 7.0 ± 1.63 to 2.8 ± 2.34 (p < 0.01, -60 ± 24.0%); muscle cramps decreased from 5.33 ± 2.06 to 1.86 ± 2.42, p < 0.01, -65 ± 28%); tiredness decreased from the initial 6.7 ± 1.34 to 1.2 ± 1.32 (p < 0.01, -82 ± 22%). We did not observe any significant changes in the placebo group. In conclusion, supplementation of statin-treated patients with CoQ10 resulted in a decrease in the symptoms of SAM, both in absolute numbers and intensity. Additional selenium supplementation was not associated with any statistically significant decrease of SAM. However, it is not possible to draw any definite conclusions, even though this study was carried out in double-blind fashion, because it involved a small number of patients.

Gaseous CO2 signal initiates growth of butyric-acid-producing Clostridium butyricum in both pure culture and mixed cultures with Lactobacillus brevis.

Microbial strains produce numerous volatile substances in the anaerobic conditions of the human intestines. The availability of CO(2) is known to be a prerequisite for bacterial growth in general. In experiments with anaerobic Lactobacillus brevis and Clostridium butyricum bacteria in the Portable Microbial Enrichment Unit (PMEU) it was shown that these strains interact; this interaction being mediated by CO(2) emission. CO(2) promoted clostridial growth in pure cultures and mixed cultures with lactobacilli. The growth of C. butyricum in pure cultures was much delayed or did not start at all without CO(2) from outside. Conversely, the onset of growth was provoked by a short (15 min) CO(2) burst. In mixed cultures the presence of lactobacilli in equal numbers speeded up the onset of clostridial growth by 10 h. If C. butyricum cultures designated as PMEU 1, 2, and 3 in cultivation syringes were chained by connecting the gas flow thereby allowing the volatiles of the preceding syringe culture to bubble to the next one, the growth started in 20, 10, or 6 h, respectively. This effect of gaseous emissions from other cultures speeding up the bacterial growth initiation was abolished if the gas was passed through sodium hydroxide to remove the CO(2). The positive contribution of lactobacilli to the growth of butyric-acid-producing clostridia documented in this simulation experiment with PMEU has in vivo implications and indicates molecular communication between the species. CO(2) is a necessary signal for the growth of clostridia, and lactobacilli can promote clostridial growth in mixed cultures where both bacteria grow well with mutual benefit.

Synthesis of some Mannich bases with dimethylamine and their hydrazones and evaluation of their cytotoxicity against Jurkat cells.

1-Aryl-3-dimethylamino-1-propanone hydrochlorides type mono Mannich bases, D series, and corresponding hydrazone derivatives, K series, were synthesized and their cytotoxicity was tested against Jurkat cells (transformed human T-lymphocytes). The aryl part was changed as phenyl in D1 and K1, 4-methylphenyl in D2 and K2, 4-methoxyphenyl in D3 and K3, 4-hydroxyphenyl in D4 and K4, 4-chlorophenyl in D5 and K5, 3-methoxyphenyl in D6 and K6, 4-fluorophenyl in D7 and K7, 4-bromophenyl in D8 and K8, 3-hydroxyphenyl in D9 and K9, and 2-acetylthiophene in D10 and K10. Of the compounds synthesized, K2, K3, K5, K6, K7, K8, K9, and K10 are reported for the first time. Cytotoxic activities of the D and K series were compared with each other to see alterations in bioactivity depending on the chemical structures in Jurkat cells. Cytotoxicities of the compounds synthesized were also compared with the reference compound, 5-fluorouracil (CAS 148-82-3). Mono Mannich bases, D1 (3.60 times), D2 (4.45 times), D3 (2.46 times), D4 (3.52 times), D5 (5.18 times), D6 (3.20 times), D7 (3.23 times), D8 (3.95 times), D9 (3.36 times) and D10 (3.99 times) had 2.46-5.18 times higher cytotoxic potency than the reference compound 5-fluorouracil against Jurkat cells, while hydrazones K1 (4.92 times), K2 (4.65 times), K3 (6.04 times), K4 (6.34 times), K5 (4.67 times), K6 (5.12 times), K7 (5.39 times), K8 (8.31 times), K9 (4.65 times) and K10 (8.65 times) had 4.65-8.65 times higher cytotoxic potency than the reference compound 5-fluorouracil against the same cell line. On the other hand, hydrazone compounds K1 (1.37 times), K3 (2.46 times), K4 (1.80 times), K6 (1.60 times), K7 (1.67 times), K8 (2.11 times), K9 (1.38 times), and K10 (2.17 times) had 1.37-2.46 times higher cytotoxic potency than their corresponding mono Mannich bases. The results of this study suggest that hydrazones were better compounds compared with the corresponding mono Mannich bases in terms of cytotoxicity, and they may serve as model compounds to develop new cytotoxic agents for further studies.

Involuntary human hand movements due to FM radio waves in a moving van.

Finland TRACT Involuntary movements of hands in a moving van on a public road were studied to clarify the possible role of frequency modulated radio waves on driving. The signals were measured in a direct 2 km test segment of an international road during repeated drives to both directions. Test subjects (n=4) had an ability to sense radio frequency field intensity variations of the environment. They were sitting in a minivan with arm movement detectors in their hands. A potentiometer was used to register the hand movements to a computer which simultaneously collected data on the amplitude of the RF signal of the local FM tower 30 km distance at a frequency of about 100 MHz. Involuntary hand movements of the test subjects correlated with electromagnetic field, i.e. FM radio wave intensity measured. They reacted also on the place of a geomagnetic anomaly crossing the road, which was found on the basis of these recordings and confirmed by the public geological maps of the area.In conclusion, RF irradiation seems to affect the human hand reflexes of sensitive persons in a moving van along a normal public road which may have significance in traffic safety.

Electromagnetic irradiation exposure and its bioindication--an overview.

Man made electromagnetic irradiation and fields cover now the globe due to the recent extensive propagation of mobile telephony. The increased load affects animals and also plants. Especially birds have been studied. Humans are also sensitive. They are good bioindicators as epidemiological methods are available. Humans can also report symptoms which cannot be directly measured with presently available technologies. The nonionizing irradiation can as the ionizing one break the DNA, damage proteins, even increase the blood brain barrier permeability, disturb the night rest, cause fatigue and hormonal disturbances. An increase of the tumours of human head has been described in correlation with the long-term mobile phone use and on that side more exposed. The regulations covering mobile telephony are already about two decades old and need re-evaluation. The multitude of irradiation and the interaction of the different wavelength exposures, i.e., frequency sensitivity is poorly known at present. We should not forget the comparative studies of different species especially those which rely in their lives on electromagnetic orientation physiology. Some countries have issued warnings on the exposures of children. The producers of mobile technology have recently warned the users not to keep those devices in active stage in skin contact.

FM-radio and TV tower signals can cause spontaneous hand movements near moving RF reflector.

For testing human sensitivity to radio frequency (RF) standing waves a movable reflecting wall was constructed. Radio waves from the radio-TV tower reflected back and formed a standing wave near the reflector. When the reflector was moved, the position of the maximums of the standing waves changed and the electromagnetic intensity changed in the body of the standing test subject. The computer with an AD-converter registered the signals of the hand movement transducer and the RF-meter with 100MHz dipole antennas. A total of 29 adults of different ages were tested. There were 9 persons whose hand movement graphs included features like the RF-meter. Six showed responses that did not correlate with the RF-meter. There were also 14 persons who did not react at all. Sensitive persons seem to react to crossing standing waves of the FM-radio or TV broadcasting signals.

Exercise training with dietary counselling increases mitochondrial chaperone expression in middle-aged subjects with impaired glucose tolerance.

BACKGROUND: Insulin resistance and diabetes are associated with increased oxidative stress and impairment of cellular defence systems. Our purpose was to investigate the interaction between glucose metabolism, antioxidative capacity and heat shock protein (HSP) defence in different skeletal muscle phenotypes among middle-aged obese subjects during a long-term exercise and dietary intervention. As a sub-study of the Finnish Diabetes Prevention Study (DPS), 22 persons with impaired glucose tolerance (IGT) taking part in the intervention volunteered to give samples from the vastus lateralis muscle. Subjects were divided into two sub-groups (IGTslow and IGTfast) on the basis of their baseline myosin heavy chain profile. Glucose metabolism, oxidative stress and HSP expressions were measured before and after the 2-year intervention. RESULTS: Exercise training, combined with dietary counselling, increased the expression of mitochondrial chaperones HSP60 and glucose-regulated protein 75 (GRP75) in the vastus lateralis muscle in the IGTslow group and that of HSP60 in the IGTfast group. In cytoplasmic chaperones HSP72 or HSP90 no changes took place. In the IGTslow group, a significant positive correlation between the increased muscle content of HSP60 and the oxygen radical absorbing capacity values and, in the IGTfast group, between the improved VO2max value and the increased protein expression of GRP75 were found. Serum uric acid concentrations decreased in both sub-groups and serum protein carbonyl concentrations decreased in the IGTfast group. CONCLUSION: The 2-year intervention up-regulated mitochondrial HSP expressions in middle-aged subjects with impaired glucose tolerance. These improvements, however, were not correlated directly with enhanced glucose tolerance.

Daily running promotes spatial learning and memory in rats.

Previous studies on exercise have shown that physical activity improves learning and memory. Present study was performed to determine the effects of acute, chronic and continuous exercise with different periods on spatial learning and memory recorded as the latency and length of swim path in the Morris water maze testing in subsequent 8 days. Four rat groups were included as follows: (1) group C, controls which did not exercise; (2) group A, 30 days treadmill running before and 8 days during the Morris water maze testing period; (3) group B, 30 days exercise before the Morris water maze testing period only; (4) group D, 8 days exercise only during the Morris water maze testing period. The results showed that chronic (30 days) and continuous (during 8 days of Morris water maze testing days) treadmill training produced a significant enhancement in spatial learning and memory which was indicated by decreases in path length and latency to reach the platform in the Morris water maze test (p<0.05). The benefits in these tests were lost in 3 days, if the daily running session was abandoned. In group D with acute treadmill running (8 days exercise only) the difference between the group A disappeared in 1 week and benefit seemed to be obtained in comparison with the controls without running program. In conclusion the chronic and daily running exercises promoted learning and memory in Morris water maze, but the benefits were lost in few days without daily running sessions in adult rats.

Effectiveness of traditional bone setting in chronic neck pain: randomized clinical trial.

OBJECTIVE: This study evaluates the effectiveness of traditional bone setting (TBS) in chronic neck pain (cNP) compared with conventional physiotherapy (PT) and massage (M). METHODS: This was a randomized clinical trial. Working-aged employed subjects with cNP (n = 105; 37 men and 68 women; mean age, 41.5 years) were randomized into TBS, PT, and M groups. Follow-up times were 1, 6, and 12 months after the treatments. Neck pain intensity (visual analog scale), perceived disability (Neck Disability Index [NDI]), and neck spine mobility measurements were used as outcomes. Global assessment was evaluated by the subjects (scale from -1 to +10). Data were analyzed using time (pre and post) by group (TBS, PT and M), 2- way analysis of variance for repeated measures. RESULTS: Neck pain decreased and NDI scores improved in all groups 1 month after the treatment (P < .001). The improvement of NDI and persons' satisfaction were significantly better after TBS. Neck spine mobility in rotation movements tended to improve significantly better and the frons-knee distance improved more after TBS. One year later, both NDI and neck pain were significantly better after TBS than in reference groups. A significant improvement was reported by 40% to 45.5% of subjects in the PT and M groups and by 68.6% in the TBS group. Bone setters' ability to communicate and to interact with patients was evaluated significantly higher. In the TBS group, the number of sick days was minimal as was the use of painkillers during 1-year follow-up compared to that in the reference groups. CONCLUSIONS: Traditional bone setting, which is a soft manual mobilization technique focusing on the muscles, joints, and ligaments, appears to be effective in cNP. Two thirds of subjects experienced it as beneficial, and it seems to be able to improve disability and pain in patients with cNP. Subjective and partially objective benefits of TBS were found in those patients more than after other interventions, and the effects lasted at least for 1 year.

Effect of aerobic fitness on the physiological stress responses at work.

OBJECTIVES: The aim of the present study was to examine the effects of aerobic fitness on physiological stress responses experienced by teachers during working hours. MATERIALS AND METHODS: Twenty-six healthy female and male teachers aged 33-62 years participated in the study. The ratings of perceived stress visual analogue scale (VAS), and the measurement of physiological responses (norepinephrine, epinephrine, cortisol, diastolic and systolic blood pressure, heart rate (HR), and trapezius muscle activity by electromyography (EMG), were determined. Predicted maximal oxygen uptake (VO(2)max) was measured using the submaximal bicycle ergometer test. The predicted VO(2)max was standardized for age using residuals of linear regression analyses. RESULTS: Static EMG activity, HR and VAS were associated with aerobic fitness in teachers. CONCLUSIONS: The results suggest that a higher level of aerobic fitness may reduce muscle tension, HR and perceived work stress in teachers.

Postoperative relieve of abnormal vasoregulation in carpal tunnel syndrome.

OBJECTIVE: To study the skin temperature changes as a sign of altered blood flow regulation due to abnormal sympathetic nerve function in carpal tunnel syndrome (CTS) and the efficacy of carpal tunnel release (CTR) operation in the alleviation of those signs and other symptoms of CTS. SUBJECTS AND METHODS: Forty-one healthy hands (n=41) of 22 volunteers and 22 hands (n=22) with clinically diagnosed carpal tunnel syndrome of 16 patients were examined. A series of infrared photos of the hands of each subject were taken and stored by using digital infrared thermography (DIRT) before and 6 months after the CTR. The temperatures of the finger tips from digit 1 (D1) to digit 5 (D5), the center point of thenar (Th) and hypothenar (Ht) eminences were measured, the median nerve index (MI=(D1-D2)+(D1-D3)+(D2-D3)) and the temperature differences between the median and the ulnar nerve distribution area (MED.ULN=(D1-D5)+(D2-D5)+(D3-D5)+(Th-Ht)) were calculated. Absolute values were used when calculating the temperature differences between different points. RESULTS: All the CTS patients were released from the CTS symptoms, i.e. numbness and pain after the operation, and the results of nerve conduction studies (NCS) were all back to normal. The MI and MED.ULN in CTS hands were significantly smaller before CTR compared to those of healthy control subjects (MI: p<0.001, MED.ULN: p<0.005), and those after CTR (p<0.005 for both parameters). The results also showed that all finger tips of the affected hand including those innervated by the ulnar nerve were cooler before but warmer after the operation. Before the operation, the non-CTS hands of the CTS patients, were also colder (although the difference was not significant) than the healthy control subjects but approached the same level after the CTR operation of the CTS hands. CONCLUSION: The results of DIRT measurements suggest that the blood flow regulation in CTS is abnormal possibly because of disturbed sympathetic vasomotor regulation and that the circulation gets normal together with the alleviation of the other symptoms of CTS as recorded 6 months after CTR operation.

Dynamic surface electromyographic responses in chronic low back pain treated by traditional bone setting and conventional physical therapy.

OBJECTIVE: This study compared the dynamic surface electromyographic (EMG) activities of back muscles and pain before and after traditional bone setting and physical therapy. METHODS: This study was a prospective clinical trial that compared surface EMG dynamic activities after traditional bone setting and physical therapy. Sixty-one patients (mean age, 41 years) with nonspecific low back pain were randomized into two subgroups by treatment. The patients underwent a dynamic EMG evaluation for which they were asked to stand and then bend forward as far as possible, stay fully flexed, and return to standing. A flexion-relaxation ratio was calculated by comparing maximal EMG activity while flexing with the average EMG activity in full flexion. Concentric (maximal EMG activity during extension) and eccentric (maximal EMG activity during flexion) ratios were also used in the analyses. RESULTS: Disability, depression, and visual analog scale scores decreased significantly after both treatments. The concentric ratio increased statistically in both groups after the treatments. The study failed to show a significant association between experienced back pain and EMG parameters. CONCLUSIONS: Both treatments seem to have a positive influence on back muscle function by improving muscle symmetry; however, the treatments had no effect on the flexion-relaxation phenomenon after 1 month. Active back exercise at home together with rehabilitation treatments might be effective and improve function for patients with chronic low back pain.

Daily running promotes spatial learning and memory in rats.

Previous studies have shown that physical activity improves learning and memory. Present study was performed to determine the effects of acute, chronic and continuous exercise with different periods on spatial learning and memory recorded as the latency and length of swim path in the Morris water maze testing in subsequent 8 days. Four rat groups were included as follows: 1- Group C (controls which did not exercise). 2- Group A (30 days treadmill running before and 8 days during the Morris water maze testing period). 3- Group B (30 days exercise before the Morris water maze testing period only) and 4- Group D (8 days exercise only during the Morris water maze testing period). The results showed that chronic (30 days) and continuous (during 8 days of Morris water maze testing days) treadmill training produced a significant enhancement in spatial learning and memory which was indicated by decreases in path length and latency to reach the platform in the Morris water maze test (p < 0.05). The benefits in these tests were lost in three days, if the daily running session was abandoned. In group D with acute treadmill running (8 days exercise only) the difference between the Group A disappeared in one week and benefit seemed to be obtained in comparison with the controls without running program. In conclusion the chronic and daily running exercises promoted learning and memory in Morris water maze, but the benefits were lost in few days without daily running sessions in adult rats. Key pointsDaily running influence on spatial memory.The velocity of learning can be influenced by running activity.Path length is important parameter for measuring the speed of learning.

Excessive texting in pathophysiology of first carpometacarpal joint arthritis.

A Case with isolated pain and swelling at the base of the left thumb is reported. The problem had lasted for 2 years, and it was getting worse with increasing pain also at the base of the right thumb. The X-ray showed a subluxation and an arthritis of the first CMCJ was diagnosed in left hand. An excision arthroplasty was successfully carried out. The excessive mobile phone use with active texting had been probably the main cause of the problem. Many, especially youngsters use their phones to text and play games a lot. The purpose of this report is to make the researchers and practitioners aware of this problem and to encourage them to record these cases that may be common in future.

Heat shock protein 60 response to exercise in diabetes: effects of alpha-lipoic acid supplementation.

The pathophysiology of diabetes includes oxidative stress and impaired heat shock protein (HSP) expression. We studied the effects of alpha-lipoic acid (LA) supplementation for 8 weeks and acute exercise on HSP60 expression and the oxidative stress marker 4-hydroxynonenal adducts (4-HNE) in streptozotocin-induced diabetic (SID) and nondiabetic control rats. Diabetes was associated with decreased HSP60 in the heart and increased levels of HSP60 and 4-HNE in the liver. LA increased HSP60 in the liver of control and diabetic rats and decreased 4-HNE in the liver and heart. Acute exercise increased liver 4-HNE, which was offset by LA. In conclusion, diabetes induced oxidative stress and impaired myocardial HSP60 expression, while LA partially offsets these alterations in a tissue-specific manner.

Plantar infrared thermography measurements and low back pain intensity.

OBJECTIVE: To study the skin temperature disorders in low back pain (LBP) patients compared with reference persons without LBP and to evaluate the relationship between pain intensity and other clinical signs and temperature abnormalities. METHODS: Sixty-five patients with unilateral chronic LBP with or without referred nonradicular leg pain (29 men and 36 women; age range, 30-51 years) and 20 reference persons without LBP (7 men and 13 women; age range, 30-49 years) participated in this study. The pain level was recorded by the use of a visual analog scale (0-100). Questionnaires and a series of spinal mobility tests (the modified Schober, straight leg-raising test, finger-floor distance, side bending) were used. Thermographic images of the low back area and legs (anterior, lateral, and posterior surfaces and the plantar surfaces of feet) were taken with an infrared video camera. RESULTS: The temperature changes in the plantar surface correlated with LBP intensity. The pain levels differed in the groups with the different types of temperature changes. There were significant lower extremity regional skin temperature alterations (at least 1 regional interside difference more than 0.3 degrees C) in most cases both in LBP patients and in reference persons, but plantar interside temperature difference was significantly higher in LBP patients. CONCLUSION: Temperature changes of the plantar surface seem to be connected with LBP intensity. Temperature measurements may be useful as an adjunctive physiological test in the evaluation and documentation of autonomic dysfunction in LBP patients.

Treadmill running reverses retention deficit induced by morphine.

Human and animal studies have suggested that exercise has benefits overall health and cognitive function. The aim of this study was to investigate the effect of treadmill running on passive avoidance learning and memory deficit in morphine-treated rats. The passive avoidance learning was measured in different time intervals (1, 2 and 24 h as well as 1 week and 1 month). Four groups of rats were included as follows: control, morphine-treated, exercised-saline and exercised-morphine-treated group. The electrical foot shock and treadmill training (2 h at a speed of 5 m/min for 10 days) were applied for all the groups. The data obtained was analyzed using unpaired Students t-test and ANOVA test with group as the independent variable, and performance in each session (avoidances and crossings) as the dependent variables. The results show that the total time staying in dark box was decreased in exercised-saline and exercised-morphine-treated rats by treadmill running (P<0.05). The avoidance learning was significantly reduced in morphine-treated group as indicated by the increased total time of staying in the dark box compared with the control group (P<0.05). We could conclude that exercise increased the delay time of entry to the dark electrical foot shock box, suggesting that morphine impaired the short-term memory and learning and this was reversed by the treadmill running.

Responses of the autonomic nervous system during periods of perceived high and low work stress in younger and older female teachers.

The aim of this study was to examine the response of the autonomic nervous system in younger (mean age 31 yrs, n=14) and older (mean age 54 yrs, n=14) healthy female teachers during work periods of perceived high and low stress. In the younger participants, heart rate, cortisol excretion rate and psychosomatic symptoms were significantly higher during the high work stress period. The older participants experienced no decrease in their heart rate and cortisol excretion during the low stress period and they exhibited no significant decrease in blood pressure after the work in the evening during both periods. It may be concluded that the recovery from the stress in the older teachers was insufficient particularly in view of their elevated diastolic blood pressure during the low work stress period. Ergonomic and individually tailored measures in terms of work time control, specific relaxation techniques, and a part-time retirement may improve the stress management of older teachers.

Reactions to cold exposure emphasize the need for weather protection in prehospital care: an experimental study.

INTRODUCTION: Exposure to cold temperature is a serious but often neglected problem in prehospital care. It not only is an uncomfortable, subjective experience, but it also can cause severe disturbances in vital functions, gradually leading to hypothermia. OBJECTIVE: The aim of this study was to examine healthy subjects' physiological and subjective reactions to cold exposure (30 minutes at -5 degrees C in the a climatic chamber) while they were lying in a protective covering. METHODS: Healthy volunteers (n = 20) participated in the experiment, which consisted of a 10-minute stabilization period of vital functions at room temperature (23 degrees C), 30 minutes of cold exposure (-5 degrees C), and a 30-minute recovery period at room temperature. Subjects lay supinely in protective covering during the entire experiment. Skin temperatures, oxygen saturation, pulse rates, pulse wave amplitude in the middle finger, and surface electromyography (EMG) activity of the major pectoral muscle were recorded continuously during the test. Before and immediately after the cold exposure, tympanic membrane temperatures were measured. In addition, subjects were asked to estimate cold using a standard scale. RESULTS: During the cold exposure, the decrease in tympanic membrane temperature was not significant. The pulse wave amplitude in the finger decreased sharply upon entering the cold chamber. Skin temperatures, especially of the fingers and toes, decreased during the cold exposure. There were no clear signs of shivering in electromyographic recordings. Subjective cold feelings followed decreasing skin temperatures. Skin temperatures did not return quickly. Even 30 minutes after the exposure, all the skin temperatures still had not returned to normal levels. However, subjective cold feeling was relieved immediately. CONCLUSIONS: Cold exposure provoked immediate protective vasoconstriction in the peripheral compartment, which caused linear decreases of local skin temperatures. This probably was triggered from the unprotected face and upper respiratory areas.