Novel harmine derivatives as potent acetylcholinesterase and amyloid beta aggregation dual inhibitors for management of Alzheimer's disease.

In this study, a series of potential ligands for the treatment of AD were synthesised and characterised as novel harmine derivatives modified at position 9 with benzyl piperazinyl. In vitro studies revealed that the majority of the derivatives exhibited moderate to potent inhibition against hAChE and Aß1 - 42 aggregation. Notably, compounds 13 and 17d displayed potent drug - likeness and ADMET properties, demonstrating remarkable inhibitory activities towards AChE (IC50 = 58.76 nM and 89.38 nM, respectively) as well as Aß aggregation (IC50 = 9.31 µM and 13.82 µM, respectively). More importantly, compounds 13 and 17d showed exceptional neuroprotective effects against Aß1 - 42-induced SH - SY5Y damage, while maintaining low toxicity in SH - SY5Y cells. Further exploration of the mechanism through kinetic studies and molecular modelling confirmed that compound 13 could interact with both the CAS and the PAS of AChE. These findings suggested that harmine derivatives hold great potential as dual - targeted candidates for treating AD.

Preparing Biochars from Cow Hair Waste Produced in a Tannery for Dye Wastewater Treatment.

A large amount of cow hair solid waste is produced in leather production, and a reasonable treatment should be developed to reduce the pollution. In this study, cow hair waste was utilized as the carbon precursor, and N2 was determined to be the most appropriate atmosphere for biochar preparation. We performed a comparison of the properties of biochars that were prepared with different methods, including direct pyrolysis, KOH activation, and the MgO template method. The characterization results show that the highest specific surface area reaches 1753.075 m2/g. Subsequently, the keratin that was extracted from cow hair and purified was used to prepare a biochar with the MgO template method, obtaining an orderly sponge structure. The biochar from cow hair waste was further used to absorb direct blue dye wastewater, and its adsorption capacity reached 1477 mg/g after 10 h with a high efficiency of regeneration. This study successfully utilized keratin-containing hair waste and provides a new source for synthesizing carbon materials for dye wastewater treatment.

Mechanisms of hyperventilation-induced lung injuries in neonatal rats.

BACKGROUND: The aim of this study was to investigate the mechanism of early inflammatory injury in neonatal ventilator-induced lung injuries (VILI). METHODS: Newborn rats were randomly assigned to groups and administrated mechanical ventilation with different tidal volumes. Morphological changes in lung tissues were observed, and the levels of interleukin-6 (IL-6), cysteinyl leukotriene mRNA (CysLT1 mRNA), and nuclear factor-κB mRNA (NF-κBp65 mRNA) in lung tissues were analyzed. RESULTS: The ventilation groups exhibited different degrees of inflammatory cell infiltration, which was aggravated as the tidal volume and ventilation time increased. The IL-6 levels of the hyperventilation 5H, conventional ventilation 5H, hyperventilation 3H, control, and normal lung-tissue group were 785.33±39.06, 701.6±33.65, 686.65±46.85, 637.63±40.55, and 635.02±65.78 pg/g, respectively. Hyperventilation increased the levels of IL-6 and NF-κBp65 mRNA as the ventilation time increased, and IL-6 was positively correlated with NF-κBp65 mRNA levels (r=0.72, P<0.01). Longer hyperventilation periods upregulate the level of CysLT1 mRNA. CysLT1 mRNA/GAPDH of the hyperventilation 5H group was 2.14±1.45 (P<0.01). CONCLUSIONS: Mechanical ventilation with a large tidal volume can cause VILI, characterized at an early stage by inflammatory responses and particularly by the increased secretion and invasion of inflammatory cytokines and inflammatory cells. The activation of the NF-κB-IL-6 signaling pathway was an important mechanism for the initiation of VILI. Additionally, CysLT1 was involved in the inflammatory VILI damage, and its upregulation occurred later than that of IL-6.

Improving characteristics of biochar produced from collagen-containing solid wastes based on protease application in leather production.

Preparation of biochar from industrial solid wastes is receiving increasing attention in recent years. In this paper, alkaline protease, neutral protease and collagenolytic protease are used in preliminary steps of leather production, which are expected to replace the traditional chemical agents while preserving quality of the finished leather. The protease application has remarkable positive influence towards characteristics of biochar prepared by collagen-containing solid wastes produced in preliminary steps. The enzymatic action time should be more than 3 h for complete permeation and catalysis, and the diameters of treated collagen fibers were in the range of 10 to 20 nm. The micro-cracks occurring on collagen fibers would have an obviously impact on the formation of biochar. The application of proteases reduce the pollution of traditional production through replacing traditional polluted chemicals, and the characteristics of biochars are obviously improved with good surface area and high carbon content approximately 70%. Its surface area can reach 967 m2/g. These biochars contain oxygen-containing functional groups, and the oxygen content of biochars are all over 20%. The enzyme application in leather production are effective to the properties of biochars prepared by collagen-containing solid wastes. This research can serve as a basis for the preparation of biochar derived from of natural bio-wastes thereby promoting the development of biomaterials.

A novel unhairing enzyme produced by heterologous expression of keratinase gene (kerT) in Bacillus subtilis.

To promote enzymatic unhairing for leather production, a new unhairing enzyme is developed. The Keratinase (kerT) gene, which is amplified from B. amyloliquefaciens TCCC11319 by PCR, is expressed in B. subtilis WB600. The recombinant KerT reduces the collagenolytic protease content as well as improving the keratinase content effectively. Therefore, the improved keratinase leads to the obviously unhairing effect, whereas the low collagenolytic protease ensures the integrity of collagen fibers in hide. It represents, the leather grain surface isn't destroyed thereby the value of finished leather can be maintained. In addition, by analyzing the properties of KerT, tits activity isn't inhibited with Na+, K+ and Ca2+ which are commonly used in leather production. The freeze-dried fermentation broth can be used directly as unhairing enzyme without addition of traditional sulfide chemicals. By evaluating the properties of unhaired hide, the results show that the collagen degradation ability of this new unhairing enzyme is slightly and it does not cause any adverse effects on the leather quality. Besides, this unhairing enzyme doesn't further degrade collagen in the time range of 8 h to 24 h, thus it is safely and easy-control in actual production. In conclusion, the enzymatic unhairing method with recombinant KerT has the potential to be more sustainable and efficient alternative than current sulphur-lime method, and it does not require the further purification thereby saving the cost.

Intracerebroventricular streptozotocin-induced Alzheimer's disease-like sleep disorders in rats: Role of the GABAergic system in the parabrachial complex.

AIM: Sleep disorders are common in Alzheimer's disease (AD) and assumed to directly influence cognitive function and disease progression. This study evaluated sleep characteristics in a rat model of AD that was induced by intracerebroventricular streptozotocin (STZ) administration and assessed the possible underlying mechanisms. METHODS: Cognition ability was assessed in the Morris water maze in rats. Sleep parameters were analyzed by electroencephalographic and electromyographic recordings. Neuronal activity in brain areas that regulate sleep-wake states was evaluated by double-staining immunohistochemistry. High-performance liquid chromatography with electrochemical detection was used to detect neurotransmitter levels. RESULTS: Fourteen days after the STZ injection, the rats exhibited sleep disorders that were similar to those in AD patients, reflected by a significant increase in wakefulness and decreases in nonrapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. The c-Fos expression analysis indicated that neuronal activity and the number of neurons in the dorsal raphe nucleus and locus coeruleus decreased in STZ-injected rats. In the ventrolateral preoptic nucleus (VLPO), the activity of γ-aminobutyric acid (GABA) neurons was suppressed. In the arousal-driving parabrachial nucleus (PBN), GABAergic activity was suppressed, whereas glutamatergic activity was promoted. The neurotransmitter analysis revealed a reduction in GABA in the VLPO and PBN and elevation of glutamate in the PBN. A direct injection of the GABAA receptor antagonist bicuculline in the PBN in normal rats induced a similar pattern of sleep disorder as in STZ-injected rats. A microinjection of GABA in the PBN improved sleep disorders that were induced by STZ. CONCLUSION: These results suggest that the reduction in GABAergic inhibition in the PBN and VLPO may be involved in sleep disorders that are induced by STZ. Our novel findings encourage further studies that investigate mechanisms of sleep regulation in sporadic AD.

Dysfunction of GABAergic neurons in the parafacial zone mediates sleep disturbances in a streptozotocin-induced rat model of sporadic Alzheimer's disease.

Sleep disturbances are prevalent among patients with Alzheimer's disease (AD) and often precede the onset and progression of dementia. However, there are no reliable animal models for investigating sleep disturbances in patients with sporadic AD (sAD), which accounts for more than 90% of all AD cases. In the present study, we characterize the sleep/wake cycles and explore a potential mechanism underlying sleep disturbance in a rat model of sAD induced via intracerebroventricular (icv) injection of streptozotocin (STZ). STZ-icv rats exhibited progressive decreases in slow wave sleep (SWS) during the light phase and throughout the light/dark cycle beginning from 7 days after STZ-icv. Additionally, increased wakefulness and decreased rapid-eye-movement (REM) and non-REM (NREM) sleep were observed from 14 days after STZ-icv. Beginning on day 7, STZ-icv rats exhibited significant decreases in delta (0.5-4.0 Hz) power accompanied by increased power in the beta (12-30 Hz) and low gamma bands (30-50 Hz) during NREM sleep, resembling deficits in sleep quality observed in patients with AD. Immunohistochemical staining revealed a significant reduction in the ratio of c-Fos-positive GABAergic neurons in the parafacial zone (PZ) beginning from day 7 after STZ-icv. These results suggest that the STZ-icv rat model is useful for evaluating sleep disturbances associated with AD, and implicate the dysregulation of GABAergic neuronal activity in the PZ is associated with sleep disturbance induced by STZ.

Tenuifolin, a saponin derived from Radix Polygalae, exhibits sleep-enhancing effects in mice.

BACKGROUND: Radix Polygalae, the dried root of Polygala tenuifolia, has been extensively used as a traditional Chinese medicine for promoting intelligence and tranquilization. Polygalasaponins extracted from the root of P. tenuifolia possess evident anxiolytic and sedative-hypnotic activities. Previous studies have reported that tenuifolin was a major constituent of polygalasaponins. PURPOSE: The currently study aims to investigate the hypnotic effect and possible mechanism of tenuifolin in freely moving mice. DESIGN/METHODS: The hypnotic effects of tenuifolin (20, 40 and 80mg/kg, p.o.) were assessed by electroencephalographic (EEG) and electromyographic (EMG) analysis. Double-staining immunohistochemistry test was performed to evaluate the neuronal activity of sleep-wake regulating brain areas. High performance liquid chromatograph- electrochemical detection (HPLC-ECD) and ultrafast liquid chromatography-mass spectrometry (UFLC-MS) were used for the detection of neurotransmitters. Locomotor activity was measured by Open-field Test. RESULTS: Tenuifolin at doses of 40 and 80mg/kg (p.o.) significantly prolonged the total sleep time by increasing the amount of non-rapid eye movement (NREM) and rapid eye movement (REM) sleep, associated with the significant increase in the bouts of episodes respectively. After administration of tenuifolin, the cortical EEG power spectral densities during NREM and REM sleep were similar to that of natural sleep (vehicle) and thus compatible with physiological sleep. Double-immunohistochemistry staining test showed that tenuifolin increased the c-Fos positive ratios of GABAergic NREM sleep-promoting neurons in ventrolateral preoptic area (VLPO), cholinergic REM sleep-promoting neurons in laterodorsal tegmental area (LDT) and pontomesencephalic tegmental area (PPT) and decreased the c-Fos positive ratios in wake-promoting neurons (locus coeruleus (LC) and perifornical area (Pef)). Neurotransmitter detections revealed that tenuifolin significantly reduced the noradrenaline (NA) levels in LC, VLPO, PPT and LDT, elevated the GABA levels in VLPO, LC and Pef and increased the acetylcholine (Ach) levels in LDT and PPT. In addition, tenuifolin did not cause any change to locomotor activity. CONCLUSION: Taken together, these results provide the first experimental evidence of the significant sleep-enhancing effect of tenuifolin in mice. This effect appears to be mediated, at least in part, by the activation of GABAergic systems and/or by the inhibition of noradrenergic systems. Moreover, this study adds new scientific evidence and highlights the therapeutic potential of the medicinal plant P. tenuifolia in the development of phytomedicines with hypnotic properties.

Tetrandrine, an alkaloid from S. tetrandra exhibits anti-hypertensive and sleep-enhancing effects in SHR via different mechanisms.

BACKGROUND: Sleep disorders have been found to be associated with hypertension in both cross-sectional and longitudinal epidemiological studies. Tetrandrine, a major component of Stephania tetrandra, is well known as an antihypertensive agent. The anti-hypertension mechanism mainly relies on its L-type calcium channel blocking property. In the previous study, tetrandrine revealed both anti-hypertension and hypnotic effects in spontaneously hypertensive rats (SHRs). PURPOSE: This study aims to elucidate whether the antihypertensive mechanism of tetrandrine in SHRs is relevant to its hypnotic effect. DESIGN/METHODS: Sleep-wake behavior of the SHRs was detected by electroencephalography (EEG) and electromyography (EMG) recordings. Blood pressure was measured by noninvasive blood pressure tail cuff test. Immunohistochemistry was performed to evaluate the noradrenergic neuronal activity. The level of norepinephrine (NE) was detected by HPLC-ECD. RESULTS: Amlodipine (100mg/kg, i.g.), the well-known L-type Ca2+ channel blockers (CCBs) exhibited remarkable antihypertensive activities in SHRs, but did not show effects on sleep of SHRs. Tetrandrine (30 and 60mg/kg/day, i.g.) significantly suppressed blood pressure of SHRs. Meanwhile, tetrandrine (60mg/kg/day, i.g.) remarkably increased non-rapid eye movement sleep (NREMS) time, bouts and mean duration. The hypnotic effect of tetrandrine was potentiated by prazosin (0.5mg/kg, i.p.) but attenuated by yohimbine (2mg/kg, i.p.). Administration of tetrandrine (60mg/kg/day, i.g.) not only significantly decreased c-Fos positive ratio of noradrenergic neurons in the locus coeruleus (LC), but also significantly decrease NE in the endogenous sleep-wake regulating pathways including LC, hypothalamus and ventrolateral preoptic nucleus (VLPO). CONCLUSION: In spite of a good potency in blocking L-type Ca2+ channel, the hypnotic effects of tetrandrine may be related to its suppressing effects on the noradrenergic system other than to block calcium channels. As a multi-targets drug, tetrandrine might be favorable to the hypertension patients who suffered poor sleep.

Ca(2+) in the dorsal raphe nucleus promotes wakefulness via endogenous sleep-wake regulating pathway in the rats.

Serotonergic neurons in the dorsal raphe nucleus (DRN) are involved in the control of sleep-wake states. Our previous studies have indicated that calcium (Ca(2+)) modulation in the DRN plays an important role in rapid-eye-movement sleep (REMS) and non-REMS (NREMS) regulation during pentobarbital hypnosis. The present study investigated the effects of Ca(2+) in the DRN on sleep-wake regulation and the related neuronal mechanism in freely moving rats. Our results showed that microinjection of CaCl2 (25 or 50 nmol) in the DRN promoted wakefulness and suppressed NREMS including slow wave sleep and REMS in freely moving rats. Application of CaCl2 (25 or 50 nmol) in the DRN significantly increased serotonin in the DRN and hypothalamus, and noradrenaline in the locus coeruleus and hypothalamus. Immunohistochemistry study indicated that application of CaCl2 (25 or 50 nmol) in the DRN significantly increased c-Fos expression ratio in wake-promoting neurons including serotonergic neurons in the DRN, noradrenergic neurons in the locus coeruleus, and orxinergic neurons in the perifornical nucleus, but decreased c-Fos expression ratio of GABAergic sleep-promoting neurons in the ventrolateral preoptic nucleus. These results suggest that Ca(2+) in the DRN exert arousal effects via up-regulating serotonergic functions in the endogenous sleep-wake regulating pathways.

Mechanisms Underlying Footshock and Psychological Stress-Induced Abrupt Awakening From Posttraumatic "Nightmares".

BACKGROUND: Posttraumatic nightmares are a highly prevalent and distressing symptom of posttraumatic stress disorder (PTSD), but have been the subject of limited phenomenological investigations. METHODS: We utilized a communication box to establish PTSD symptoms in rats through exposure to footshock stress (FS) and psychological stress (PS). The immunohistochemical test and high-performance liquid chromatography with electrochemical detection were used to detect the activity and monoamine levels in the rats' arousal systems. RESULTS: Twenty-one days after traumatic stress, 14.17% of FS and 12.5% of PS rats exhibited startled awakening, and the same rats showed hyperfunction of the locus coeruleus/noradrenergic system and hypofunction of the perifornical nucleus/orexinergic system. Changes in serotonin levels in the dorsal raphe nucleus showed opposite trends in the FS and PS rats that were startled awake. No differences were found in other sleep/arousal systems. CONCLUSION: These results suggest that different clinically therapeutic strategies should be considered to treat different trauma-induced posttraumatic nightmares.

Phosphorylation of CaMKII in the rat dorsal raphe nucleus plays an important role in sleep-wake regulation.

The Ca(2+) modulation in the dorsal raphe nucleus (DRN) plays an important role in sleep-wake regulation. Calmodulin-dependent kinase II (CaMKII) is an important signal-transducing molecule that is activated by Ca(2+) . This study investigated the effects of intracellular Ca(2+) /CaMKII signaling in the DRN on sleep-wake states in rats. Maximum and minimum CaMKII phosphorylation was detected at Zeitgeber time 21 (ZT 21; wakefulness state) and ZT 3 (sleep state), respectively, across the light-dark rhythm in the DRN in rats. Six-hour sleep deprivation significantly reduced CaMKII phosphorylation in the DRN. Microinjection of the CAMKII activation inhibitor KN-93 (5 or 10 nmol) into the DRN suppressed wakefulness and enhanced rapid-eye-movement sleep (REMS) and non-REM sleep (NREMS). Application of a high dose of KN-93 (10 nmol) increased slow-wave sleep (SWS) time, SWS bouts, the mean duration of SWS, the percentage of SWS relative to total sleep, and delta power density during NREMS. Microinjection of CaCl2 (50 nmol) in the DRN increased CaMKII phosphorylation and decreased NREMS, SWS, and REMS. KN-93 abolished the inhibitory effects of CaCl2 on NREMS, SWS, and REMS. These data indicate a novel wake-promoting and sleep-suppressing role for the Ca(2+) /CaMKII signaling pathway in DRN neurons. We propose that the intracellular Ca(2+) /CaMKII signaling in the dorsal raphe nucleus (DRN) plays wake-promoting and sleep-suppressing role in rats. Intra-DRN application of KN-93 (CaMKII activation inhibitor) suppressed wakefulness and enhanced rapid-eye-movement sleep (REMS) and non-REMS (NREMS). Intra-DRN application of CaCl2 attenuated REMS and NREMS. We think these findings should provide a novel cellular and molecular mechanism of sleep-wake regulation.

Different neural circuitry is involved in physiological and psychological stress-induced PTSD-like "nightmares" in rats.

Posttraumatic nightmares are a core component of posttraumatic stress disorder (PTSD) and mechanistically linked to the development and maintenance of this disorder, but little is known about their mechanism. We utilized a communication box to establish an animal model of physiological stress (foot-shock [FS]) and psychological stress (PS) to mimic the direct suffering and witnessing of traumatic events. Twenty-one days after traumatic stress, some of the experimental animals presented startled awakening (i.e., were startled awake by a supposed "nightmare") with different electroencephalographic spectra features. Our neuroanatomical results showed that the secondary somatosensory cortex and primary auditory cortex may play an important role in remote traumatic memory retrieval in FS "nightmare" (FSN) rats, whereas the temporal association cortex may play an important role in PS "nightmare" (PSN) rats. The FSN and PSN groups possessed common emotion evocation circuits, including activation of the amygdala and inactivation of the infralimbic prefrontal cortex and ventral anterior cingulate cortex. The decreased activity of the granular and dysgranular insular cortex was only observed in PSN rats. The present results imply that different types of stress may cause PTSD-like "nightmares" in rodents and identified the possible neurocircuitry of memory retrieval and emotion evocation.

Involvement of adrenoceptors, dopamine receptors and AMPA receptors in antidepressant-like action of 7-O-ethylfangchinoline in mice.

AIM: 7-O-ethylfangchinoline (YH-200) is a bisbenzylisoquinoline derivative. The aim of this study was to investigate the antidepressant-like action and underlying mechanisms of YH-200 in mice. METHODS: Mice were treated with YH-200 (15, 30, and 60 mg/kg, ig) or tetrandrine (30 and 60 mg/kg, ig) before conducting forced swimming test (FST), tail suspension test (TST), or open field test (OFT). RESULTS: YH-200 (60 mg/kg) significantly decreased the immobility time in both FST and TST, and prolonged the latency to immobility in FST. YH-200 (60 mg/kg) was more potent than the natural bisbenzylisoquinoline alkaloid tetrandrine (60 mg/kg) in FST. Pretreatment with α1-adrenoceptor antagonist prazosin (1 mg/kg), ß-adrenoceptor antagonist propranolol (2 mg/kg), dopamine D1/D5 receptor antagonist SCH23390 (0.05 mg/kg), dopamine D2/D3 receptor antagonist haloperidol (0.2 mg/kg) or AMPA receptor antagonist NBQX (10 mg/kg) prevented the antidepressant-like action of YH-200 (60 mg/kg) in FST. In contrast, pretreatment with α2 adrenoceptor antagonist yohimbine (1 mg/kg) augmented the antidepressant-like action of YH-200 (30 mg/kg) in FST. Chronic administration of YH-200 (30 and 60 mg/kg for 14 d) did not produce drug tolerance; instead its antidepressant-like action was strengthened. Chronic administration of YH-200 did not affect the body weight of mice compared to control mice. CONCLUSION: YH-200 exerts its antidepressant-like action in mice via acting at multi-targets, including α1, α2 and ß-adrenoceptors, D1/D5 and D2 /D3 receptors, as well as AMPA receptors.

[Rosiglitazone improves learning and memory impairment of 3 x Tg mice].

This study is to investigate the protective effect of rosiglitazone (RSG) against learning and memory impairment of APP/PS1/tau transgenic mice. AD mice model was replicated by using 6-month APP/PS1/tau transgenic mice. The learning and memory ability of mice was evaluated by Morris water maze and Western blotting assays was applied to measure the phosphorylation and O-glycosylation of Tau and neurofilaments (NFs) protein. The results demonstrated that RSG could reverse the learning and memory deficits of 3 x Tg mice significantly. It was also found that RSG could suppress the hyperphosphorylation of Tau and NFs protein levels and increase the glycosylation expression of Tau and NFs proteins in 3 x Tg mice brain. Together, RSG ameliorates cognitive impairments of 3 x Tg mice via the alleviation of the hyperphosphorylated Tau and NFs proteins burden in the brain.

The neuroprotection of liraglutide on Alzheimer-like learning and memory impairment by modulating the hyperphosphorylation of tau and neurofilament proteins and insulin signaling pathways in mice.

The aim of this study was to investigate the effect of liraglutide on Alzheimer-like learning and memory impairment in mice, which were intracerebroventricularly (i.c.v.) injected with streptozotocin (STZ). Twenty-four mice were randomly divided into three groups: control (CON), AD model (STZ), and liraglutide-treated (LIR). The results show that both hyperphosphorylated tau and neurofilament proteins had deceased protein glycosylation and the tau bound to microtubules was lower in the STZ group compared to the CON group. The expression of JNK phosphorylation was higher and the number of Fluoro-Jade-B-positive degenerative neurons was increased in the STZ group as compared to both the CON and liraglutide groups. Escape latency in the STZ group was longer than that in both the CON and LIR groups, while the number of hidden platform crossings in path length was less than that in the other two groups. Liraglutide decreased the hyperphosphorylation levels of tau and neurofilament proteins, increased protein O-glycosylation, increased tau bound to microtubules, and also significantly improved the learning and memory ability of the mice. These results suggest that the effects of liraglutide on decreasing the hyperphosphorylation of tau and neurofilament proteins by enhancing O-glycosylation of neuronal cytoskeleton protein, improving the JNK and ERK signaling pathway, and reducing neural degeneration may be related to its protective effects on AD-like learning and memory impairment induced by i.c.v. injection of STZ. Our results indicate that GLP-1 analogs represent a novel treatment strategy for Alzheimer's disease.

[An epidemiological survey of attention deficit hyperactivity disorder in school-age children in Shenzhen].

OBJECTIVE: To investigate the prevalence of attention deficit hyperactivity disorder (ADHD) and behavior problems among school-age children in Shenzhen City of Guangdong. METHODS: A total of 10553 students in Grades 1-6 from different primary schools in Shenzhen City were assessed by Conners Parent Symptom Questionnaire (PSQ) and Conners Teacher Rating Scale (TRS). Children showing abnormalities according to PSQ or TRS were further assessed according to the diagnostic standard for ADHD as laid out in the diagnostic and statistical manual for mental disorders- 4th edition (DSM-Ⅳ). RESULTS: A total of 8193 PSQ and TRS assessments were completed. The children were aged from 7 to 13 years. The total prevalence rate was 7.60% by PSQ and 5.59 % by TRS. Four hundred and forty-two children were diagnosed having ADHD by DSM-Ⅳ, with a prevalence rate of 5.39%. There were significant differences in the prevalence rate of ADHD among children aged 7 to 13 years (χ2=21.613, P<0.05). In children aged 7 to 9 years, the prevalence rate was higher (above 6%). The prevalence rate of ADHD in boys was significantly higher than in girls (6.65% vs 3.12%; P<0.05). Impulsion and hyperactivity (79.6%), learning (60.6%) and conduct disorders (52.0%) were the main behavioral problems in children with ADHD. The prevalence of learning disorders was higher in girls than in boys. Conclusions The prevalence rate of ADHD in children from primary schools in Shenzhen City is 5.39%, and it is higher in children aged 7 to 9 years. Boys have a higher prevalence rates of ADHD than girls. Impulsion and hyperactivity, learning and conduct disorders are common problems in children with ADHD.

[Examination of cerebral electrical admittance plethysmogram in healthy newborns].

OBJECTIVE: Cerebral electrical admittance plethysmography is a novel noninvasive technique for evaluating cerebral hemodynamics. This study aimed to measure the reference values of cerebral electrical admittance plethysmogram in healthy newborns. METHODS: Bilateral cerebral electrical admittance plethysmography was performed in 40 healthy newborns. RESULTS: The values of various indexes of cerebral electrical admittance plethysmogram in 40 newborns were obtained by this technique. The index of Admittance Differential Loop (ADL) I+II at the third and fourth days after birth was significantly higher than that at the first day of life (P < 0.05). There were significant differences in the index of ADL I+II and the ratio of Hs to b-S (Hs/ b-S) among different birth weight groups (P < 0.05). No significant differences were found in all the indexes of cerebral electrical admittance plethysmogram between the left and right brain of newborns. Gender and parturition mode had also no effects on these indexes. CONCLUSIONS: The research reported the reference values of cerebral electrical admittance plethysmogram in healthy newborns. The postnatal age and birth weight are influencing factors for the cerebral electrical admittance plethysmogram.