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http://www.webmedcentral.com/images/Header_Logo.giftext/html2012-03-26T12:36:34+01:00http://www.webmedcentral.com/Dr. John SmythiesThe Functional Anatomy of the Claustrum: The Net That Binds.
http://www.webmedcentral.com/article_view/3182
Crick and Koch suggested in 2005 that the claustrum might be engaged in sensory binding operations related to consciousness. This might involve, they suggested, widespread waves of information traveling within the claustrum that might depend on networks of gap-junction linked neurons, which were especially sensitive to the timing of inputs. But they did not suggest any specific system to do this. The purpose of this present paper is to suggest what this mechanism might be. The basic thesis is that the claustrum is a spike coincidence–detecting device, constructed of large number of small simple identical nerve nets. These function as GABA-modulated ‘AND gates’ that convert the separate packets of unbound information in its inputs into an efferent signal that carries the binding information essential for consciousness and other brain functions. This function may also be relevant to processing of synchronized oscillation by the claustrum. Different anatomical regions of the claustrum may exert this function for sensory binding, computation of the significance of reinforcement in a complex environment, and other higher brain functions. We also suggest the outlines of a mechanism by which the cortex may process this input from the claustrum. We review the manner in which this hypothesis explains the present data. There is at present no other detailed hypothesis in this field.Key words: Claustrum, consciousness, binding, coincidence detection, AND gate, GABAergic interneurons, gap-junction linked networks, salvinorin A.text/html2012-09-15T17:26:38+01:00http://www.webmedcentral.com/Prof. Lester IngberInfluence of Macrocolumnar EEG on Ca Waves
http://www.webmedcentral.com/article_view/3701
A “smoking gun” for explicit top-down neocortical mechanisms that directly drive bottom-up processes that describe memory, attention, etc. The top-down mechanism considered are macrocolumnar EEG firings in neocortex, as described by a statistical mechanics of neocortical interactions (SMNI), developed as a magnetic vector potential A. The bottom-up process considered are Ca2+ waves prominent in synaptic and extracellar processes that are considered to greatly influence neuronal firings. Here, the complimentary effects are considered, i.e., the influence of A on Ca2+ momentum, p. The canonical momentum of a charged particle in an electromagnetic field, ?= p + qA (SI units), is calculated, where the charge of Ca2+ is q = 2e, e is the magnitude of the charge of an electron, valid in both classical and quantum mechanics. It is shown that A is large enough to influence p. This suggests that, instead of the common assumption that Ca2+ waves contribute to neuronal activity, they may in fact at times be caused by the influence of A of larger-scale EEG.text/html2012-11-01T14:36:23+01:00http://www.webmedcentral.com/Dr. Toshifumi KumaiSynchronization Among Endplate Potential Oscillations in Jaw Closing Muscles
http://www.webmedcentral.com/article_view/3800
Surface electromyograms (EMGs) in tooth clenching were recorded in a monopolar manner from paired anterior temporalis and masseter muscles of six subjects. The EPP (endplate potential) component was extracted from raw EMGs of the muscles using a digital filter. The component showed two phases, early slow wave and following oscillation. From the deflection pattern of the early EPP, the location of neuromuscular junction of the masseter muscle could be estimated at its inferior portion, and that of the anterior temporalis muscle near the temple. Frequencies of EPP oscillations for the muscles were around 30Hz, and the oscillation showed synchronization among the ipsilateral and contralateral temporalis and masseter muscles, suggesting the existence of a neural mechanism integrating sensory signals of different roots. The frequencies for non-preferred sided clenching tended to be lower than those for preferred sided clenching of subjects. This led us to conjecture that abnormal tremors in humans would be the result of a decline of the frequency of the EPP oscillation. It is concluded that the contraction of jaw closing muscles is regulated in an oscillating fashion of the EPP, and that the cooperative work among the muscles is controlled by synchronizing the oscillations.text/html2012-12-06T14:23:36+01:00http://www.webmedcentral.com/Dr. Akio HiuraChanges in Response Behaviors to Noxious Heat and Mechanical Stimuli After Carrageenan-induced Inflammation in Mice Treated with Capsaicin 2 or 15 days After Birth
http://www.webmedcentral.com/article_view/3727
The aim of the present study was to investigate the cause of normal response behaviors to noxious heat despite the marked loss of small neurons in the dorsal root ganglion (DRG) as a result of neonatal capsaicin treatment. Capsaicin (50 mg/kg) was injected subcutaneously (s.c.) into mice on either day P2 or P15; control mice received a vehicle injection. Twenty days after the capsaicin injection, 2% carrageenan (20 µL) was injected into the right hind paw of each animal. Twenty-four hours after the carrageenan injection, behavioral tests using noxious heat stimuli (NHS; Hargreaves method) and noxious mechanical stimuli (NMS; von Frey method) were performed using the control and capsaicin-treated mice. Pre-carrageenan measurements were used as the baseline values for each group. After the experiments, the mice were perfused with a mixture of 4% paraformaldehyde and 0.2% picric acid in a 0.1-M phosphate buffer (pH 7.4). The L4 and L5 DRGs were extracted, sectioned using a cryostat, and immunostained using a TRPV1 antibody and reacted with isolectin IB4. The P2 capsaicin-injected mice exhibited a marked increase in their analgesic responses to NHS, compared with both their baseline values and the respective control mice. Both the capsaicin-treated and control animals exhibited significant hyperalgesia in response to NMS. Naturally, the control P15 mice exhibited a shorter response time to NHS than their baseline values, while the capsaicin-injected P15 mice exhibited increased algesia comparable to the baseline values of the control. The capsaicin-injected mice also exhibited algesia in response to NMS. The number of TRPV1-immunoreactive (ir) small neurons decreased by 90% in the P2 capsaicin-injected mice and 45% in the P15 capsaicin-injected mice, whereas an increase in IB4-positive neurons was seen in both the P2 and P15 capsaicin-injected mice. In association with the decrease in larger neurons, the numbers of smaller neurons were increased in both P2 and P15 capsaicin-injected mice. TRPV1-ir small neurons are closely correlated with inflammatory heat pain perception, suggesting the enhancement of an unknown acute noxious heat sensor in the present study. The present findings indicate that noxious mechanical stimuli can be sensed despite the presence or absence of TRPV1-ir or IB4-positive neurons.text/html2014-01-23T05:18:49+01:00http://www.webmedcentral.com/Prof. Rajnish K SinghalSalivary Aβ-40, Aβ-42, IGF-I, IGF-II, Alpha Amylase, IL-1β, and TNF-alpha in Alzheimer\'s Disease: A Useful Diagnostic Tool
http://www.webmedcentral.com/article_view/4440
A very significant challenge in Alzheimer's disease today is the discovery of suitable technologies for detection of the disease that are easy to use, cost effective and non-invasive. In this study we demonstrate that saliva biomarkers are a suitable option for detection of the disease. Accordingly, we collected saliva samples by three different methods from age and gender matched Alzheimer's patients and normal healthy subjects. Salivary Aβ-40, Aβ-42, IGF-I, IGF-II, alpha amylase, IL-1β, and TNF-alpha levels were analyzed. Of the three methods, passive drooling was found to be the best saliva collection method for analysis of biomarkers of Alzheimer's disease. There were significant differences in the salivary biomarkers evaluated between patients and controls. Additional results from our studies confirm that Aβ-40, Aβ-42, IGF-I, IGF-II, alpha amylase, IL-1β, and TNF-alpha are appropriate diagnostic biomarkers for Alzheimer's disease.
Key words: Saliva, Alzheimer's disease, biomarkers
text/html2015-11-09T04:24:29+01:00http://www.webmedcentral.com/Prof. Uner TanGait Analysis in Uner Tan Syndrome Cases with Key symptoms of Quadrupedal Locomotion, Mental Impairment, and Dysarthric or No Speech
http://www.webmedcentral.com/article_view/5016
Introduction: Uner Tan syndrome (UTS) consists of quadrupedal locomotion (QL), impaired intelligence and dysarthric or no speech. Previously, I described the walk of cases with UTS as diagonal sequence (DS) because of ipsilateral limb interference, mostly observed in nonhuman primates with DS QL. The only gait analysis performed for UTS were a few cases with lateral sequence (LS) QL. The current work presents a gait analysis of UTS in more families. Childs [3] described this man as follows:
Methods: Hip and knee angles during quadrupedal standing were measured in UTS cases, healthy controls with requested QL, and nonhuman primates. Limb phases were assessed from video footages, as the percent of the hind limb's stride durations.
Results: UTS cases and nonhuman primates exhibited quadrupedal standing with straight legs nearly perpendicular to the ground. Healthy individuals could not walk quadrupedally like UTS cases. They could perform QL only with flexed legs. UTS cases and healthy individuals with free (flexed-leg) QL used predominantly lateral sequence-diagonal couplet (LSDC) walks. Terrestrial primates preferred DS gaits. The healthy individuals with free QL were similar to arboreal primates in quadrupedal posture.
Conclusions: Although these results do not seem to support the thesis of locomotor evolution in reverse, nobody knows with certainty who our ancestors were or how they walked, and so the possibility of UTS as an example for the ancestral reappearance of QL in human beings cannot be positively excluded. This locomotor evolution in reverse was supported by experimental evidence, which proved reverse evolution as a scientific fact.text/html2015-11-10T08:43:08+01:00http://www.webmedcentral.com/Prof. Uner TanGait Analysis in Uner Tan Syndrome Cases with Key Symptoms of Quadrupedal Locomotion, Mental Impairment, and Dysarthric or No Speech
http://www.webmedcentral.com/article_view/5017
Introduction: Uner Tan syndrome (UTS) consists of quadrupedal locomotion (QL), impaired intelligence and dysarthric or no speech. Previously, I described the walk of cases with UTS as diagonal sequence (DS) because of ipsilateral limb interference, mostly observed in nonhuman primates with DS QL. The only gait analysis performed for UTS were a few cases with lateral sequence (LS) QL. The current work presents a gait analysis of UTS in more families.
Methods: Hip and knee angles during quadrupedal standing were measured in UTS cases, healthy controls with requested QL, and nonhuman primates. Limb phases were assessed from video footages, as the percent of the hind limb’s stride durations.
Results: UTS cases and nonhuman primates exhibited quadrupedal standing with straight legs nearly perpendicular to the ground. Healthy individuals could not walk quadrupedally like UTS cases. They could perform QL only with flexed legs. UTS cases and healthy individuals with free (flexed-leg) QL used predominantly lateral sequence-diagonal couplet (LSDC) walks. Terrestrial primates preferred DS gaits. The healthy individuals with free QL were similar to arboreal primates in quadrupedal posture.
Conclusions: Although these results do not seem to support the thesis of locomotor evolution in reverse, nobody knows with certainty who our ancestors were or how they walked, and so the possibility of UTS as an example for the ancestral reappearance of QL in human beings cannot be positively excluded. This locomotor evolution in reverse was supported by experimental evidence, which proved reverse evolution as a scientific fact.text/html2015-12-10T10:51:45+01:00http://www.webmedcentral.com/Prof. Uner TanQuadrupedal Locomotor Characteristics of Uner Tan Syndrome Cases, Healthy Humans, and Nonhuman Primates in Evolutionary Perspectives
http://www.webmedcentral.com/article_view/5032
08 December 2015
Dear Editor:
I would like to submit my paper entitled “Quadrupedal Locomotor Characteristics of Uner Tan Syndrome Cases, Healthy Humans, and Nonhuman Primates in Evolutionary Perspectives, for possible publication in the Journal of WebmedCentral). This is a revised version of my article appeared in WMC (Tan U. Gait Analysis in Uner Tan Syndrome Cases with Key Symptoms of Quadrupedal Locomotion, Mental Impairment, and Dysarthric or No Speech. WebmedCentral NEUROSCIENCES 2015;6(11):WMC005017), revised according to the Reviewer’s comments.
Uner Tan syndrome was first identified in 2005 as a unique syndrome characterized by the habitual use of quadrupedal locomotion, severe truncal ataxia, dysarthric or no speech, and severely impaired intellectual abilities. No quantitative gait analysis was carried on these cases until 2014, when the QL was characterized by others as lateral sequence similar to healthy human adults, but in a small sample size from only one family. The submitted work included a representative sample size from 10 families hitherto discovered in Turkey, and reports a new quantitative gait analysis of Uner Tan syndrome cases, healthy human infants, healthy human individuals and nonhuman primates. It addresses the fact that UTS cases walk with straight rather than flexed legs, and the results show that while the QL is mostly lateral sequence, there are similarities in gait characteristics with terrestrial primate locomotion, whereas the QL in healthy individuals had similarities with arboreal primate locomotion. These findings have implications in the evolution of bipedal locomotion in human beings and in the quadrupedal locomotion in UTS cases.
I hope this revised version of my article will meet with your approval.
Yours faithfully,
Prof. Dr. Uner Tan, M.D., Ph.D.
Honorary member of the Turkish Academy of Sciences, Ankara, Turkey
E-mail: unertan37@yahoo.com