Biomedical subjects

Uner Tan

Publications and source records attributed to Uner Tan.

At least 19 recordsLinked to original sources

PubMed2006

The mechanism of acupuncture and clinical applications.

This study presents the result of the studies explaining the effects of acupuncture on various systems and symptoms. It has been determined that endomorphin-1, beta endorphin, encephalin, and serotonin levels increase in plasma and brain tissue through acupuncture application. It has been observed that the increases of endomorphin-1, beta endorphin, encephalin, serotonin, and dopamine cause analgesia, sedation, and recovery in motor functions. They also have immunomodulator effects on the immune system and lipolithic effects on metabolism. Because of these effects, acupuncture is used in the treatment of pain syndrome illnesses such as migraine, fibromyalgia, osteoarthritis, and trigeminal neuralgia; of gastrointestinal disorders such as disturbance at gastrointestinal motility and gastritis; of psychological illnesses such as depression, anxiety, and panic attack; and in rehabilitation from hemiplegia and obesity.

Acupuncture↗

PubMed2006

The treatment of obesity by acupuncture.

The present study is an investigation of the results of the studies on the effects of acupuncture application therapy on obesity. It has been reported that acupuncture application in obesity treatment is effective in procuring weight loss. It can affect appetite, intestinal motility, and metabolism, as well as emotional factors such as stress. Increases in neural activity in the ventromedial nuclei of the hypothalamus, in tone in the smooth muscle of the stomach and in levels of enkephalin, beta endorphin, and serotonin in plasma and brain tissue have also been observed with the application of acupuncture. It has been observed that acupuncture application to obese people increases excitability of the satiety center in the ventromedial nuclei of the hypothalamus. Acupuncture stimulates the auricular branch of the vagal nerve and raises serotonin levels. Both of these activities have been shown to increase tone in the smooth muscle of the stomach, thus suppressing appetite. Among other things, serotonin enhances intestinal motility. It also controls stress and depression via endorphin and dopamine production. In addition to these effects, it is thought that the increase in plasma levels of beta endorphin after acupuncture application can contribute to the body weight loss in obese people by mobilizing the body energy depots through lipolithic effect.

Acupuncture Therapy↗

PubMed2006

Middle-finger reflex.

A new reflex is described: middle-finger extensor reflex elicited by percussion of tendon insertion of musculus extensor digitorum communis in forearm. Following percussion using a reflex hammer, two EMG responses from the belly of the muscle were recorded: a short latency monosynaptic reflex with a latency of 31.4 +/- 1.5 ms (M1), and a long-latency middle-finger reflex with a mean latency of 64.8 +/- 6.31 ms (M2), the former being a monosynaptic extensor reflex, and the latter belonging to a spino-cortico-spinal reflex circuitry. It was suggested that the middle-finger extensor reflex elicited by radial nerve afferents and efferents (C7-C8) would be of clinical and theoretical importance.

Afferent Pathways↗

PubMed2006

A new syndrome with quadrupedal gait, primitive speech, and severe mental retardation as a live model for human evolution.

The author has discovered a new syndrome with quadrupedal gait, flexed head and body, primitive speech, severe mental retardation, and mild cerebellar signs with a disturbed conscious experience. This syndrome was exhibited by 5 of 19 children from a consanguineous family. The pedigree demonstrated a typical autosomal-recessive inheritance. The genetic nature of this syndrome suggests a backward stage in human evolution, which is most probably caused by a genetic mutation, rendering, in turn, the transition from quadrupedality to bipedality. This would then be consistent with theories of punctuated evolution. On the other hand, the extensor motor system causing a resistance of the body against the gravity may actually be subjected to evolutionary forces. This new syndrome may be used as a live model for human evolution. An accompanying video clip for this article is available as a downloadable file accompanying the official online version of International Journal of Neuroscience. To access it, click on the issue link for 116(3), then select this article. A download option appears at the bottom of this abstract.

Adolescent↗

PubMed2006

Long-term effects of mild exercise on intraocular pressure in athletes and sedentary subjects.

The long-term effects of acute submaximal exercise on intraocular pressures (IOPs) of right-and left-eyes and recovery times to basement levels of IOP in postexercise periods in sedentary and physically fit subjects were investigated. Twenty-five sedentary and 24 physically fit subjects, ranging in age 17 to 22 years, participated. Intraocular pressures were measured by a pneumotonometer. Measurements were taken in the morning at about nine (at rest) and immediately, 30 min and 2 h after acute submaximal exercise. In sedentary subjects, IOPs of both right- and left-eyes decreased immediate after exercise, but, these decreases in both eyes continued 30 min and 2 h after exercise. In physically fit subjects, IOPs of both right- and left-eyes increased immediate after exercise, but decreased after 30 min exercise compared to basement levels, and this decrease continued 2 h after exercise. Acute submaximal exercise decreased IOPs of right and left eyes over a period 2 h in sedentary and physically fit subjects. IOP reducing after exercise was different between right- and left-eyes in sedentary subjects. These results suggest that exercise can be used in ocular hypertension treatment.

Adolescent↗

PubMed2006

Effect of acute submaximal exercise on intraocular pressure in athletes and sedentary subjects.

The existing literature is controversial regarding the relationship between physical fitness and intraocular pressure (IOP). Therefore, the effects of acute submaximal exercise on IOP were compared in athletes and sedentary subjects. Acute exercise increased IOP in male athletes, but had no effect in sedentary men. Also, it decreased IOP in sedentary women, but had no effect in female athletes. Sex and physical fitness both were significant factors influencing the changes in IOP due to exercise. These results suggest that acute dynamic exercise is useful to decrease IOP in sedentary women, but not in male athletes. These results may help glaucoma screeners.

Adolescent↗

PubMed2006

Evidence for "Unertan Syndrome" and the evolution of the human mind.

A new family exhibiting "Unertan Sydnrome" was discovered. The pedigree analysis showed marriages between relatives. This family was similar to the first one (see Tan, 2006a), providing a firm evidence for the new syndrome. The affected children showed habitual quadrupedal walking gait, that is, they walked on wrists and feet with straight legs and arms. Their heads and bodies were mildly flexed; they exhibited mild cerebellar signs, and severe mental retardation. The pedigree demonstrated a typical autosomal-recessive inheritance. The genetic nature of this syndrome suggests a backward stage in human evolution (devolution), which would be consistent with theories of punctuated evolution. The results reflected a new theory on the evolution of human beings. That is, the evolution of humans would in fact be the evolution of the extensor motor system, responsible for upright posture, against the gravitational forces. This would be coupled with the emergence of the human mind, which can be considered a reflexion of the human motor system, in accord with the psychomotor theory (see Tan, 2005a). The most important characteristic of the newly emerged human mind was the resistance against gravitational forces. This was the resistive mind, the origins of human creativity.

Abnormalities, Multiple↗

PubMed2006

Evidence for "Uner Tan Syndrome" as a human model for reverse evolution.

"Uner Tan Syndrome" was further studied in a second family. There was no cerebellar atrophy, except a mild vermial atrophy in MRI scans of the affected individuals. This is not, however, the pathogenesis of the "Uner Tan Syndrome", since in the first and second families there were bipedal men exhibiting very similar MRI scans. The second family may also be considered a live model for reverse evolution in human beings. The present work provided evidence for a reverse evolution: (i) quadrupedality; (ii) primitive mental abilities including language; (iii) curved fingers during wrist-walking of the quadrupedal woman; (iv) arm to leg ratios being close to those of the human-like apes. The quadrupedal individuals were raised in separate places, so that they could not imitate each other, excluding the socio-cultural factors contributing to the habitual quadrupedal gait. The results are consistent with the single gene theory, suggesting a single gene controlling multiple behavioral traits, and the psychomotor theory, and a co-evolution of the human mind, an emergent property of the motor system expressed by human language.

Adult↗

PubMed2005

Relationship between eye dominance and pattern electroretinograms in normal human subjects.

The authors conducted a study in 100 non-smoker healthy normal human subjects to find a relationship between eye dominance and macular function as tested by using transient stimulus and electroretinography. Eye preference procedure was carried out using two reference points and pattern electroretinograms (PERGs) were recorded using black and white checks, each check subtending 23'. Trace averager was retriggered every 300 milliseconds (ms) with data collection time of 150 ms. The difference in PERG P50 amplitudes between right and left eyes was analyzed using Student's t test. There was no significant difference in PERG P50 amplitudes between the right and left eye dominant subjects as well as no significant differences between the right and left eyes in right eye dominants and left eye dominants, but in the left-eye dominant group the left eye PERG P50 amplitudes were significantly higher in females than males. Although pattern-reversal visual evoked potentials of healthy subjects provide electrophysiological evidence of lateralization in the nervous system, sensory eye dominance seems to have no correlation with macular function.

Adult↗

PubMed2005

Hand preference in Turkish population.

The distribution of hand preference (self report) was studied in siblings and their parents originating from all parts of Turkey (N = 22,461). In total sample and siblings, there were significantly more right-handed women than men, and significantly more left-handed men than women--no significant sex difference for parents' handedness. The relative number for the right-handed parents significantly exceeded that for the right-handed siblings; the relative number for the left-handed siblings significantly exceeded that for the left-handed parents. It was concluded that there may be a sex difference in hand preference, but being only about 1% more left-handed men, and only about 1% more right-handed women; the right-handedness in new generation (siblings) is less than that in old generation (parents), due to freeing from cultural pressures against the left-hand use in everyday activities.

Adolescent↗

PubMed2005

Correlations between nonverbal intelligence and nerve conduction velocities in right-handed male and female subjects.

A neurological theory of intelligence suggesting a direct correlation between nerve conduction velocity and psychometric intelligence was tested. Cattell's Culture Fair Intelligence Test was used to asses the nonverbal intelligence (IQ) of subjects. The motor median nerve conduction velocity from right hand of males was positively correlated with IQ. In subjects with no familial sinistrality (FS-), the motor ulnar-nerve conduction velocity from the right and left hands of males negatively correlated with IQ; there were inverse correlations between IQ and nerve conduction velocity (motor median nerve from right, sensory median nerve from right and left) in females. In subjects with familial sinistrality (FS+), IQ directly correlated with nerve conduction velocity from motor median (right and left), sensory median (right), and motor ulnar (right) nerves, but only in males. The speed hypothesis and neurological theory of intelligence were not supported by these results, which, in contrast, emphasized the importance of sex and familial sinistrality in any theory of intelligence.

Adolescent↗

PubMed2005

Effects of exercise on visual evoked potentials.

The aim of this study was to investigate the effects of acute or habitual exercise on visual evoked potentials (VEP). The study group consisted of 9 female and 7 male volleyball players and the control group contained 9 female and 7 male students who were not involved in any sportive activity. The N75, P100, and N145 latency and amplitudes were measured before and after exercise. Intragroup comparison was made to evaluate the acute effects and intergroup comparison for the chronic effects of exercise. Significant differences were noted between athletes and the sedentary subjects in terms of pre-exercise left-N145 latencies and amplitudes and left -P100 amplitudes. Right-eye N145 latencies of inactive female subjects obtained before and after exercise were also statistically different. The results suggest that acute and habitual exercise affects the VEP responses independent from the body temperature and other physiological parameters. Small sized pre-exercise P100 amplitudes in the athletes can be attributed to the effect of rapid visual-activity-demanding sports on the central nervous system. Visual evoked potentials maybe used as neurophysiological criteria in defining the performance of an athlete.

Adult↗

PubMed2004

Second to fourth digit ratio and hand skill in Austrian children.

Prenatal exposure to testosterone is thought to promote the development of the right-hemisphere and increase the incidence of sinistrality. A direct test of this hypothesis has previously been problematic because of the difficulty of indirectly assessing prenatal sex steroid exposure. Evidence now suggests that the ratio between the length of the second and fourth digits (2D:4D) is related to prenatal testosterone exposure. We tested whether digit ratio is related to the degree of hand skill such that low 2D:4D (indicating high levels of testosterone in utero) may be correlated with enhanced left-hand performance. In right-handed children, high 2D:4D correlated with improved right-hand skill and low 2D:4D correlated with enhanced left-hand skill. Correlations were found to be similar for girls and for boys. Since low 2D:4D has been previously reported to be associated with faster left-hand speed compared to right in Afro-Caribbean children with very low mean 2D:4D, the present finding in a Caucasian population with high mean 2D:4D suggests that a tendency of improved left-hand performance due to prenatal testosterone may be found across ethnic groups.

Austria↗

PubMed2004

N-terminal heterogenicity of amyloid protein examined in Alzheimer's disease.

Alzheimer's disease is the major cause of dementia in humans. The affected brain shows characteristic abnormal filamentous proteins that accumulate intracellularly as neurofibrillary tangles, and extracellularly as senile plaques, as well as in cerebral blood vessels. The extracellular deposits are an amyloid protein, which is highly insoluble. In our study, we intended to show that the N-terminus of amyloid A4 protein can change in length and sequence in Alzheimer's disease, and possibly in other dementias.

Alzheimer Disease↗

PubMed2004

Sleep quality and immune functions in rheumatoid arthritis patients with and without major depression.

The purpose of this study was to determine the discriminative factors between rheumatoid arthritis (RA) patients with and without major depression (MD). We assessed subjective sleep quality, pain, and cell-mediated immune functions in RA patients with (n = 20) and without (n = 20) MD by using Pittsburgh Sleep Quality Index (PSQI), visual analogue scale (VAS), and fluorescein isothiocyanat (FITC) labeled CD3, CD4, CD8, CDI9, CD45, CD56, and HLADR T monoclonal antibodies by flow cytometry. We found that the RA patients with MD had significantly higher pain level, poorer sleep equality, higher HDRS points, and higher HLADR T cell level than those without MD; and that these variables are discriminant factors between patient groups. These findings suggest that the RA patients with MD may be differentiated from those without MD by using VAS, PSQI, and HLADR levels; that these variables correctly classify the depressed and non depressed groups up to an accuracy level of 96.8%.

Adolescent↗

PubMed2003

Early diagnosis of diabetic neuropathy using double-shock stimulation of peripheral nerves.

OBJECTIVE: The purpose of this study was to determine the changes in the amplitudes of a sensory nerve action potential (NAP) to a conditioning stimulus given prior to a test stimulus at 2-8 ms intervals in healthy subjects and patients with diabetes mellitus with no clinical signs of neuropathy and normal nerve conduction velocities (NCVs), to be able to diagnose peripheral neuropathy at its very early stages. METHODS: NAPs in the superficial branch of the radial nerve were recorded in healthy subjects (28 women and 7 men) and type II diabetes patients without neuropathy (22 women and 12 men). Radial nerve was first stimulated with a single shock and then with double shocks at intervals of 2, 3, 4, 5, 6, 7, and 8 ms; NAP amplitudes and NAP1/NAP2 ratios were calculated in normals and diabetics. NCVs were within the normal ranges (>50 m/s) in all subjects. RESULTS: Of the independent variables--group (control, patient), sex (male, female), and hand (right, left)--only group significantly influenced NAP amplitude; mean NAP amplitude (single shock) was significantly lower in patients than controls. NAP1/NAP2 ratios were slightly below one (facilitation) in controls; it was above one at 1-8 ms stimulus intervals (inhibition) in diabetics, which was strongest at smallest intervals, gradually decreasing, and almost disappearing as the stimulus interval approached 8 ms. CONCLUSIONS: Using double-shock stimuli, an early diagnosis of peripheral neuropathy would be possible in diabetics without clinical signs of peripheral neuropathy and exhibiting no slowing in NCV.

Action Potentials↗

PubMed2003

A simple chaotic neuron model: stochastic behavior of neural networks.

We have briefly reviewed the occurrence of the post-synaptic potentials between neurons, the relationship between EEG and neuron dynamics, as well as methods of signal analysis. We propose a simple stochastic model representing electrical activity of neuronal systems. The model is constructed using the Monte Carlo simulation technique. The results yielded EEG-like signals with their phase portraits in three-dimensional space. The Lyapunov exponent was positive, indicating chaotic behavior. The correlation of the EEG-like signals was.92, smaller than those reported by others. It was concluded that this neuron model may provide valuable clues about the dynamic behavior of neural systems.

Electroencephalography↗

PubMed2003

Differential contributions of right and left brains to paw skill in right- and left-pawed female rats.

Paw preference and paw frequency was studied in female rats. Paw preference was assessed using a modified version of food reaching task in quadrupedal position. Of 68 rats, 56 (82.4%) were right-handed, 7 (10.3%) were left-handed, and 5 (7.4%) were mixed-handed. There were significantly more right-handers than left-handers. The distribution of right minus left (L) paw reach (R + L = 50) was not U-shaped, it was J-shaped like in humans. Estrus cycle was a significant factor influencing the right-paw entry scores: most of left-handers were in estrus and proestrus, most of left -handers were in estrus, and most of mixed-handers were in postestrus. In right- and non-right- handers, the frequency of right-paw usage (right-hand skill) increased linearly with testing days, but the frequency of left-hand usage (left-hand skill) did not show significant changes with the successive testing days. Controlling for body weight and estrus only accentuated these results. It was concluded that distribution of hand preference in rats is J-shaped and there is a right-sided population bias in handedness in rats like in humans. The results suggested that motor learning in paw skill is mainly involved the left brain in right- and mixed-handed rats, not the right brain: only the left brain has the inbuilt capacity for motor learning in female rats. Such an asymmetric cognitive control in an animal model may have a major impact in many aspects of biology in respect to normal functioning, superior talents, and disease (see Geschwind, 1985).

Animals↗