Biomedical subjects

Desheng Wang

Publications and source records attributed to Desheng Wang.

9 recordsLinked to original sources

PubMed2006

Numerical generation of hyperspherical harmonics for tetra-atomic systems.

A numerical generation method of hyperspherical harmonics for tetra-atomic systems, in terms of row-orthonormal hyperspherical coordinates-a hyper-radius and eight angles-is presented. The nine-dimensional coordinate space is split into three three-dimensional spaces, the physical rotation, kinematic rotation, and kinematic invariant spaces. The eight-angle principal-axes-of-inertia hyperspherical harmonics are expanded in Wigner rotation matrices for the physical and kinematic rotation angles. The remaining two-angle harmonics defined in kinematic invariant space are expanded in a basis of trigonometric functions, and the diagonalization of the kinetic energy operator in this basis provides highly accurate harmonics. This trigonometric basis is chosen to provide a mathematically exact and finite expansion for the harmonics. Individually, each basis function does not satisfy appropriate boundary conditions at the poles of the kinetic energy operator; however, the numerically generated linear combination of these functions which constitutes the harmonic does. The size of this basis is minimized using the symmetries of the system, in particular, internal symmetries, involving different sets of coordinates in nine-dimensional space corresponding to the same physical configuration.

Journal Article↗

PubMed2006

Characteristics of IA currents in adult rabbit cerebellar Purkinje cells.

Classical conditioning the rabbit nictitating membrane involves changes in synaptic and intrinsic membrane properties of cerebellar Purkinje cell dendrites, and a 4-aminopyridine (4-AP)-sensitive potassium channel underlies these membrane properties. We characterized I(A) currents in adult, rabbit Purkinje cells to determine whether I(A) is the target channel involved in learning. Whole-cell recordings of Purkinje cell somas and dendrites revealed a fast activating and inactivating current with half maximal activation at -27.08 +/- 3.48 mV and -25.51 +/- 1.15 mV in somas and dendrites, respectively; half maximal inactivation at -58.91 +/- 2.34 mV and -49.90 +/- 2.58 mV; and a recovery time constant of 22.81 +/- 1.92 ms and 16.60 +/- 4.26 ms. Outside-out patch recordings from cerebellar Purkinje cell somas confirmed these 4-AP-sensitive currents with half maximal activation at -13.85 +/- 1.17 mV and half maximal inactivation at -55.07 +/- 5.54 mV. More importantly, there was an overlap of activation and incomplete inactivation at potentials from -60 to -40 mV, suggesting a "window" current that was responsible for subthreshold variations of membrane potential and might underlie conditioning-specific increases in Purkinje cell excitability. The potassium current was inhibited by 4-AP and by Heteropodatoxin, a specific blocker of Kv4.2 and Kv4.3 channels, but not by Stromatoxin, a blocker of Kv4.2 channels. Mouse monoclonal antibody labeling identified both Kv4.3 and Kv4.2 subunits in the granule cell layer but only Kv4.3 subunits in the molecular layer. This is the first demonstration of A-type currents in adult, rabbit Purkinje cells that may play a role in regulating membrane potential and firing frequency and comprise the target channel mediating conditioning-specific changes of excitability in rabbit Purkinje cell dendrites.

Animals↗

PubMed2006

Effects of 4-aminopyridine on classical conditioning of the rabbit (Oryctolagus cuniculus) nictitating membrane response.

A large body of data suggests that potassium channels may play an important role in learning and memory. Previous in-vitro research in a number of species including Hermissenda and the rabbit suggests that a 4-aminopyridine-sensitive transient potassium channel may be involved in classical conditioning. We investigated the effects of in-vivo 4-aminopyridine administration (0.5 mg/kg) on classical conditioning of the rabbit nictitating membrane response using a battery of tests designed to assess the associative, sensory, and motor contributors of 4-aminopyridine to responding. 4-Aminopyridine enhanced both classical conditioning and conditioning-specific reflex modification compared with a saline vehicle control, and these effects had several nonassociative components including an increase in the frequency of responding to both the conditioned and the unconditioned stimuli, suggesting a sensitizing effect of the drug. Although 4-aminopyridine can have peripheral effects, it may also modify cerebellar excitability or hippocampal neurotransmitter balance resulting in heightened responsiveness to stimulation.

4-Aminopyridine↗

PubMed2005

Conditioning-specific reflex modification of rabbit (Oryctolagus cuniculus) heart rate.

Conditioning-specific reflex modification (CRM) describes changes in rabbit (Oryctolagus cuniculus) nictitating membrane responses (NMR) to an unconditioned stimulus (US) when the US is tested by itself after pairings of tone and electrodermal stimulation. Although CRM has been replicated, it is unclear whether it occurs in response systems other than that of the NMR. The authors report that CRM of rabbit heart rate (HR) can occur following HR conditioning. A US that elicits HR acceleration before conditioning can elicit HR deceleration after conditioning. The rabbits' electrocardiograms showed both HR conditioning and HR CRM were correlated with an increased PQ interval--an index of parasympathetic function mediated by the vagus. The data suggest conditioned HR deceleration can generalize from conditioned stimulus to US as a function of conditioning.

Animals↗

PubMed2004

Beta-fibrinogen promoter -455 G/A (HaeIII) polymorphism prediction of plasma fibrinogen but not of ischemic cerebrovascular disease.

OBJECTIVE: The -455 G/A (HaeIII) polymorphism of beta-fibrinogen gene influences levels of plasma fibrinogen. We further investigated whether it influences the risk of ischemic cerebrovascular disease. METHODS: We accumulated 134 acute ischemic cerebrovascular disease (ICVD) cases and compared their -455 G/A status with a control group (n = 166). The beta-fibrinogen gene -455 G/A polymorphism was analyzed for all subjects by PCR-RFLP with the restrictive enzyme HaeIII. RESULTS: Plasma fibrinogen was higher in AA homozygous participants (341 mg/dL) than in participants carrying the G allele: GA (290 mg/dL), GG (298 mg/dL) in the control group. Plasma fibrinogen was also higher in AA homozygous patients (353 mg/dL) than in cases carrying the G allele: GA (287 mg/dL), GG (302 mg/dL) in the ICVD group. However, there was no significant association between beta-fibrinogen gene -455 G/A polymorphism and ICVD group. CONCLUSIONS: Although a small effect cannot be excluded, beta-fibrinogen gene -455 G/A polymorphism is an independent predictor of plasma fibrinogen, but not of ischemic cerebrovascular disease.

Alleles↗

PubMed2003

Videomimicography: the standards of normal revised.

BACKGROUND: Studies aiming to objectively evaluate facial movements have focused on the technique of measurement, whereas the most pertinent measurements of basic facial movements have not been well characterized. OBJECTIVE: To determine the best normal measures of 5 basic facial movements in healthy patients. METHODS: In 5 healthy subjects, 11 facial landmarks were placed on the face, and 5 movements (forehead lift, eye closure, nose wrinkling, lip puckering, and smiling) with maximal contraction force were requested. Each subject repeated each movement 3 times, and the entire session was repeated on 4 different days. No specific immobilization of the head was performed. The session was filmed with a digital camera, and the frames with maximal movement were selected. Measurements were performed with Osiris public domain image analysis software. For each measure, the change from rest was computed. Intersubject and intrasubject variability were determined by a multivariate analysis of variance. RESULTS: In all movements, surface changes (mean +/- SD) were higher than distance changes. For forehead lifting and eye closure, the best measure was the eye surface changes of 13% +/- 5% and -32% +/- 9%, respectively. For nasal wrinkling, lip puckering, and smiling, the best measures were the paranasal area (change, -28% +/- 9%), upper lip area (change, -23% +/- 8%), and mouth area (change, 63% +/- 21%), respectively. Most distance changes were below 10%. Same-day repeatability variation was below 15%, and day-to-day repeatability variation was below 7%. In healthy subjects, more than 80% of the total variation was accounted for by the intersubject variability. CONCLUSIONS: Videomimicography is a simple and objective linear measurement system based on facial surface changes. The measures exhibit good reliability.

Adult↗

PubMed2003

Postinfectious encephalitis (21 cases appended).

OBJECTIVE: To report 21 cases of postinfectious encephatitis according to ICD-NA, postinfectious/parainfectious encephalitis is an independent disease. METHODS: Using the uniform criteria provided by The Council of State and Territorial Epidemiologists (CSTE) and Centers for Disease Control and Prevention (CDC), we diagnosed postinfectious encephalitis among patients admitted to The First Hospital of Harbin Medical University and analyzed the characteristics of these cases. RESULTS: All the patients had histories of preceding infection, and most of them suffered from mental and conscious disorders. Adrenocortical hormone was effective. CONCLUSIONS: Postinfectious encephalitis is an independent disease. According to this article, about 10% patients with encephalitis admitted to our hospital are postinfectious.

Adolescent↗

PubMed2002

[Effect of local mild hypothermia on treatment of acute intracerebral hemorrhage, a clinical study].

OBJECTIVE: To observe the effect of local mild hypothermia on treatment of acute intracerebral hemorrhage. METHODS: Forty patients with acute intracerebral hemorrhage were matched according to age and state of illness at a ratio of one to one and then randomly divided into two groups of 20 patients: routine group (dehydrant, antihypertensive agent, etc were given) and hypothermia group (in addition to the general treatment, controllable semiconductor brain-protecting freezer was used to produce local hyperthermia at temperature of 6 degrees C for 48 hours). Immediately after admission and one week and 2 weeks after treatment cranium CT was conducted and the volume of cerebral edema was calculated by Tada's formula. RESULTS: There was no significant difference in the volume of edema and scores according to European Stroke Scale between the two groups at admission (P > 0.05). The volumes of edema one week and 2 weeks after therapy were 17.4 +/- 6.2 and 13.1 +/- 5.8 milliliter respectively in hypothermia group, both significantly lower than those in the routine group (33.8 +/- 16.0 and 22.4 +/- 12.2 milliliter respectively, P < 0.05). The scores according to European Stroke Scale one week and 2 weeks after therapy were 62.1 +/- 10.8 and 70.3 +/- 10.7 in hypothermia group, both significantly higher than those in the routine group (52.8 +/- 10.9 and 60.5 +/- 10.9 respectively, P < 0.05). No side effect caused by local hyperthermia was observed during the therapy. CONCLUSION: A safe and reliable treatment, local mild hypothermia combined with routine therapy is effective in protecting the brain of patients with intracerebral hemorrhage.

Adult↗

PubMed2002

[Epidemiological survey on epilepsy among rural populations in five provinces in China].

OBJECTIVE: To investigate the prevalence of epilepsy and its treatment gap in rural areas of China. METHODS: A door-to-door epidemiological survey on epilepsy was conducted among 55616 rural residents in 5 counties, each in a province (Heilongjiang, Ningxia, Shanxi, Henan, and Jiangsu) selected by random cluster sampling. All people diagnosed or suspected as epileptic during the screening phase were rechecked by neurologists. RESULTS: A definite diagnosis of epilepsy was made among 387 people with a prevalence rate 7.0 per thousand (age-adjusted rate 6.8 per thousand). The prevalence of active epilepsy was 4.6 per thousand, and the incidence of epilepsy was 28.8/100 000. Of the people with epilepsy, 40.6% had not been treated, 35.4% were treated irregularly. The treatment gap of active epilepsy was 62.6%. CONCLUSION: The prevalence of epilepsy in the rural areas in China was much higher than it was reported previously. About two thirds of the patients with epilepsy has not received regular treatment. A rational intervention strategy should be developed as soon as possible.

Adolescent↗