Publications by authors named "Yu-Hong Gao"

16 Publications

  • Page 1 of 1

Disrupted Small-world Networks are Associated with Decreased Vigilant Attention after Total Sleep Deprivation.

Neuroscience 2021 09 19;471:51-60. Epub 2021 Jul 19.

Department of Neurology, The Second Medical Center, Sleep Medicine Research Center, National Clinical Research Centre for Geriatric Diseases, Chinese PLA General Hospital, Beijing 100853, China; School of Medicine, Nankai University, Tianjin 300071, China. Electronic address:

Sleep deprivation critically affects vigilant attention. Previous neuroimaging studies have revealed altered inter-regional functional connectivity after sleep deprivation, which may disrupt topological properties of brain functional networks. However, little is known about alterations in the topology of intrinsic connectivity and its involvement in attention performance after sleep deprivation. In the current study, we investigated the topological properties of brain networks derived from resting-state functional magnetic resonance imaging of 26 healthy men in rested wakefulness (RW) state and after 36 h of total sleep deprivation (TSD). In the predefined sparsity threshold range, both global and nodal network properties were evaluated based on graph theory analysis. Vigilant attention was assessed using the psychomotor vigilance test (PVT) before and after TSD. Furthermore, Pearson's correlation analyses were conducted to explore the association between altered network properties and changed PVT performance after TSD. At the global level, the brain functional networks in the TSD state showed a significantly lower small-world coefficient than RW, with decreased global efficiency. At the nodal level, the altered regions were selectively distributed in frontoparietal networks, sensorimotor networks, temporal regions, and salience networks. More specifically, the altered clustering coefficient in the posterior superior temporal sulcus (pSTS) and insula, and altered local efficiency in pSTS were further associated with PVT performance after TSD. Our results suggest that the topological properties of brain functional networks are disrupted, and aberrant topology of temporal networks and salience networks may act as neural signatures underlying the vigilant attention impairments after TSD.
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http://dx.doi.org/10.1016/j.neuroscience.2021.07.010DOI Listing
September 2021

Altered insula-prefrontal functional connectivity correlates to decreased vigilant attention after total sleep deprivation.

Sleep Med 2021 08 5;84:187-194. Epub 2021 Jun 5.

Department of Neurology, The Second Medical Center, Sleep Medicine Research Center, National Clinical Research Centre for Geriatric Diseases, Chinese PLA General Hospital, Beijing, 100853, China; School of Medicine, Nankai University, Tianjin, 300071, China. Electronic address:

Background: Sleep deprivation can robustly affect vigilant attention. The insula is a key hub of the salience network that mediates shifting attention between endogenous and exogenous states. However, little is known regarding the involvement of insular functional connectivity in impaired vigilant attention after total sleep deprivation (TSD). The purpose of this study is to explore the alterations in insular functional connectivity and its association with vigilant attention performance following TSD.

Methods: Twenty-six adult men were enrolled in the study. Participants underwent two counterbalanced resting-state functional magnetic resonance imaging (rs-fMRI) scans, once in rested wakefulness (RW) and once after 36 h of TSD. Seed-based functional connectivity analysis was performed using rs-fMRI data for the left and right insula. The vigilant attention was measured using a psychomotor vigilance test (PVT). Furthermore, Pearson correlation analysis was conducted to investigate the relationship between altered insular functional connectivity and PVT performance.

Results: Compared to RW, enhanced functional connectivity was observed between the insula and prefrontal cortex and anterior cingulate cortex, while reduced functional connectivity was observed between the insula and temporal, parietal, and occipital regions following TSD. Moreover, altered insular functional connectivity with the prefrontal cortex, ie superior frontal gyrus and middle frontal gyrus, and inferior temporal gyrus was correlated with PVT performance after TSD.

Conclusion: Our results suggest that insular coupling with the prefrontal cortex and inferior temporal gyrus may act as neural indicators for vigilant attention impairment, which further reveals the critical role of the salience network in cognitive decline following TSD.
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http://dx.doi.org/10.1016/j.sleep.2021.05.037DOI Listing
August 2021

Altered functional connectivity between the nucleus basalis of Meynert and anterior cingulate cortex is associated with declined attentional performance after total sleep deprivation.

Behav Brain Res 2021 Jul 25;409:113321. Epub 2021 Apr 25.

School of Medicine, Nankai University, Tianjin, 300071, China; Department of Neurology, The Secondary Medical Center, Sleep Medicine Research Center, National Clinical Research Centre for Geriatric Diseases, Chinese PLA General Hospital, Beijing, 100853, China. Electronic address:

Background: Sleep deprivation can markedly influence vigilant attention. The nucleus basalis of Meynert (NBM), the main source of cholinergic projections to the cortex, plays an important role in wakefulness maintenance and attention control. However, the involvement of NBM in attentional impairments after total sleep deprivation (TSD) has yet to be established. The purpose of this study is to investigate the alterations in NBM functional connectivity and its association with the attentional performance following TSD.

Methods: Thirty healthy adult males were recruited in the study. Participants underwent two resting-state functional magnetic resonance imaging (rs-fMRI) scans, once in rested wakefulness (RW) and once after 36 h of TSD. Seed-based functional connectivity analysis was performed using rs-fMRI data for the left and right NBM. The vigilant attention was measured using a psychomotor vigilance test (PVT). Furthermore, Pearson correlation analysis was conducted to investigate the relationship between altered NBM functional connectivity and changed PVT performance after TSD.

Results: Compared to RW, enhanced functional connectivity was observed between right NBM and bilateral thalamus and cingulate cortex, while reduced functional connectivity was observed between left NBM and right superior parietal lobule following TSD. Moreover, altered NBM functional connectivity with the left anterior cingulate cortex was negatively correlated with PVT performance after TSD.

Conclusion: Our results suggest that the disrupted NBM-related cholinergic circuit highlights an important role in attentional performance after TSD. The enhanced NBM functional connectivity with the anterior cingulate cortex may act as neural signatures for attentional deficits induced by sleep deprivation.
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http://dx.doi.org/10.1016/j.bbr.2021.113321DOI Listing
July 2021

Relation of Decreased Functional Connectivity Between Left Thalamus and Left Inferior Frontal Gyrus to Emotion Changes Following Acute Sleep Deprivation.

Front Neurol 2021 26;12:642411. Epub 2021 Feb 26.

Department of Neurology, Secondary Medical Center, National Clinical Research Center for Geriatric Disease, Chinese PLA General Hospital, Beijing, China.

The thalamus is a key node for sleep-wake pathway gate switching during acute sleep deprivation (ASD), and studies have shown that it plays a certain role in emotion changes. However, there are no studies on the association between the thalamus and emotion changes in ASD. In this study, we used resting-state functional magnetic resonance imaging (R-fMRI) to explore whether changes in the functional connections between the thalamus and other brain regions are related to emotion changes and further explored the function of the thalamus under total ASD conditions. Thirty healthy, right-handed adult men underwent emotional assessment according to the Profile of Mood States Scale and R-fMRI scans before and after ASD. The correlations between changes in functional connectivity between the thalamus and other brain regions and emotion changes were then studied. Positive emotions and psychomotor performance were reduced, and negative emotions were increased following ASD. The functional connections between the left thalamus and left middle temporal gyrus, left inferior frontal gyrus, right thalamus, right inferior temporal gyrus, left middle temporal pole gyrus, right calcarine, left cuneus, left rectus and left medial superior frontal gyrus were significantly altered. Decreased functional connectivity between left thalamus and left inferior frontal gyrus related to emotion changes following ASD. This study finds that functional changes in the thalamus are associated with emotion changes during ASD, suggesting that the left thalamus probably plays an essential role in emotion changes under ASD conditions.
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http://dx.doi.org/10.3389/fneur.2021.642411DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7952868PMC
February 2021

[Effects of water and nitrogen coupling on grain yield formation and nitrogen accumulation, transportation of oil flax in dryland].

Ying Yong Sheng Tai Xue Bao 2020 Mar;31(3):909-918

College of Agronomy, Gansu Agricultural University/Gansu Provincial Key Laboratory of Arid Land Crop Science, Lanzhou 730070, China.

A completely random split zone experiment with irrigation as main plots and nitrogen application rate as sub-plots was carried out to examine the optimal water-nitrogen coupling mode for oil flax planting in dryland. There were three irrigation levels, no irrigation (0 m·hm, I), irrigation at 1200 m·hm(I) and at 1800 m·hm(I); and three nitrogen application rates, no nitrogen (0 kg N·hm, N), 60 kg·N hm(N) and 120 kg·N hm(N). We investigated nitrogen accumulation content at different growth stages, nitrogen transport characteristics after anthesis, grain yield and nitrogen utilization efficiency of oil flax. Results showed that the coupling effects of water and nitrogen application on nitrogen uptake in different organs, nitrogen accumulation during different growth stages and grain yield of dry land oil flax varied greatly. Under no irrigation, nitrogen application was beneficial to stem nitrogen absorption at anthesis and maturity stages, but 120 kg N·hm inhibited it at different irrigation levels. At the 1200 m·hm(I) irrigation level, foliar nitrogen content at anthesis stage increased first and then decreased with increasing nitrogen rates, and N increased foliar nitrogen content by 11.0% and 28.9% respectively compared with N and N. At the 1800 m·hm(I) irrigation level, nitrogen application increased foliar nitrogen content at maturity stage, with that in N and N treatments being 39.7% and 26.9% higher than N, respectively. The effects of water-nitrogen coupling on nitrogen accumulation in different growth stages of oil flax was mainly shown after budding stage. Under the same irrigation level, N promoted and N inhibited nitrogen accumulation in each stage after budding. Nitrogen application increased nitrogen transport rate and contribution rate of leaves and stems under I and I. The coupling of I and N significantly increased the number of effective capsules per plant and grain yield of oil flax (6.6%-22.8%), which was a suitable water-nitrogen coupling management mode in this area.
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http://dx.doi.org/10.13287/j.1001-9332.202003.028DOI Listing
March 2020

[Responses of water consumption characteristics and grain yield of maize to different nitrogen form ratios with full film mulching on double ridges and planting in furrows].

Ying Yong Sheng Tai Xue Bao 2019 Oct;30(10):3426-3434

Gansu Provincial Key Laboratory of Arid Land Crop / College of Agronomy, Gansu Agricultural University, Lanzhou 730070, China.

To optimize the effects of nitrate (NO-N) to ammonium (NH-N) ratios on water consumption characteristics, grain yield and water use efficiency (WUE) of maize under full film mulching on double ridges, a field experiment was conducted at semi-arid Loess Plateau of Gansu Province, China during 2015 to 2017 cropping seasons. The treatments with different ratios of NO-N to NH-N included: N (1:0), N (1:1), N (1:3) and N (3:1). The results showed that different NO-N/NH-N ratios had significant impacts on soil water storage in 0-200 cm soil layer. Treatment N had the lowest soil water storage. Treatment N significantly increased total water consumption by 2.9%, 1.9% and 0.9% in 2015, and 2.3%, 1.4%, and 2.2% in 2017, compared with N, N and N treatments, respectively. Compared with the other treatments, treatment N increased grain yield by 3.3%-9.9%, 3.5%-24.2% and 8.3%-36.1% and improved WUE by 1.6%-6.8%, 4.9%-21.8%, and 6.6%-32.9% in 2015, 2016 and 2017, respectively. Treatment N had the highest partial productivity of nitrogen fertilizer, followed by N, N and N, respectively. We recommended treatment N as the best nitrate and ammonium ratio to improve water use efficiency, N partial productivity, and grain yield of maize in arid and semi-arid Loess Plateau.
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http://dx.doi.org/10.13287/j.1001-9332.201910.025DOI Listing
October 2019

Effects of different mulching modes on soil nitrate concentration and grain yield of Linum usitatissimum in dry land.

Ying Yong Sheng Tai Xue Bao 2018 Oct;29(10):3283-3292

Gansu Provincial Key Laboratory of Arid Land Crop/College of Agronomy, Gansu Agricultural University, Lanzhou 730070, China.

To investigate soil NO-N dynamics and yield increasing effect of mulching planting for Linum usitatissimum (oil flax) in semi-arid Loess Plateau, we examined the effects of three mul-ching modes (whole field plastic mulching and micro ridges with soil cover and bunch-seeding; whole field plastic mulching with soil cover and bunch-seeding; and straw mulching with strips) on seed yield and distribution of soil NO-N during the main growth periods of oil flax, with the conventional planting model as control (CK) in 2015 and 2016. Results showed that the average yield under mulching modes was increased by 56.1% (2015) and 22.7% (2016). The treatment of whole field plastic mulching with soil cover and bunch-seeding had the highest grain yield. Mulching treatments significantly increased soil water content. Soil water content was increased first and then reduced in the whole growth stage of oil flax. The soil NO-N content was gradually decreased during the oil flax growth process. In both years, NO-N content in 0-40 cm soil depth under mul-ching treatments were increased by 3.1%-18.6% (2015) and 5.1%-16.4% (2016) at budding stage of oil flax, respectively. The whole field plastic mulching with soil cover and bunch-seeding treatment showed the larges increases across all treatments. In 2015, NO-N accumulation in 0-100 cm soil depth between the flowering and maturity stages of oil flax were increased by 10.2%-22.2% and 8.6%-21.4%, respectively. Especially during the more rainfall period of maturity stage, NO-N accumulation in 0-40 cm soil depth was significantly enhanced by 3.3%-4.9% than that in 40-100 cm soil depth. It indicated that more rainfall could slow down the migration of NO-N to the lower layer under the mulching modes in the maturity stage. In 2016, high temperature and drought at late growth stages had a great influence on oil flax growth. The NO-N accumulation in 0-100 cm soil depth at the maturity stage was increased by 6.6%-18.0%. There was significant correlation between NO-N content and grain yield during the main growth stages of oil flax. In conclusion, the whole field plastic mulching with soil cover and bunch-seeding treatment was the most appropriate way of oil flax production in arid and semi-arid area.
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http://dx.doi.org/10.13287/j.1001-9332.201810.022DOI Listing
October 2018

Three new diphenyl ether derivatives from the fermentation products of an endophytic fungus Phomopsis fukushii.

J Asian Nat Prod Res 2019 Apr 17;21(4):316-322. Epub 2018 Jan 17.

c Key Laboratory of Tobacco Chemistry of Yunnan Province , China Tobacco Yunnan Industrial Co., Ltd , Kunming 650231 , China.

Three new diphenyl ethers (1-3), together with four known isopentylated diphenyl ethers derivatives (4-7), were isolated from the fermentation products of an endophytic fungus Phomopsis fukushii. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1-3 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. The results revealed that compounds 1 and 2 showed strong inhibitions with inhibition zone diameters (IZD) of 20.2 ± 2.5 mm and 17.9 ± 2.2 mm, respectively. Compound 3 also showed good inhibition with IZD 15.2 ± 1.8 mm. The IZD data of compound 1 is close to that of positive control with IZD 21.9 ± 2.1 mm.
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http://dx.doi.org/10.1080/10286020.2017.1421177DOI Listing
April 2019

Selenium Deficiency Affects the mRNA Expression of Inflammatory Factors and Selenoprotein Genes in the Kidneys of Broiler Chicks.

Biol Trace Elem Res 2016 May 23;171(1):201-7. Epub 2015 Sep 23.

College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China.

The aim of this study was to investigate the influence of Se deficiency on the transcription of inflammatory factors and selenoprotein genes in the kidneys of broiler chicks. One hundred fifty 1-day-old broiler chicks were randomly assigned to two groups fed with either a low-Se diet (L group, 0.033 mg/kg Se) or an adequate Se diet (C group, 0.2 mg/kg Se). The levels of uric acid (UA) and creatinine (Cr) in the serum and the mRNA levels of 6 inflammatory factors and 25 selenoprotein genes in the kidneys were measured as the clinical signs of Se deficiency occurred at 20 days old. The results indicated that the contents of UA and Cr in the serum increased in L group (p < 0.05), and the mRNA levels of the inflammatory factors (NF-κB, iNOS, COX-2, and TNF-α) increased in L group (p < 0.05). Meanwhile, the mRNA levels of PTGEs and HO-1 were not changed. In addition, 25 selenoprotein transcripts displayed ubiquitous expression in the kidneys of the chicks. The mRNA levels of 14 selenoprotein genes (Dio1, Dio2, GPx3, Sepp1, SelH, SelI, SelK, Sepn1, SelO, SelW, Sep15, SelT, SelU, and SelS) decreased, and 9 selenoprotein genes (GPx1, GPx2, GPx4, SelPb, Txnrd1, Txnrd2, Txnrd3, SPS2, and SelM) increased in L group (p < 0.05), but the Dio3 and Sepx1 mRNA levels did not change. The results indicated that Se deficiency resulted in kidney dysfunction, activation of the NF-κB pathway, and a change in selenoprotein gene expression. The changes of inflammatory factor and selenoprotein gene expression levels were directly related to the abnormal renal functions induced by Se deficiency.
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http://dx.doi.org/10.1007/s12011-015-0512-3DOI Listing
May 2016

Xanthone derivatives from the fermentation products of an endophytic fungus Phomopsis sp.

Fitoterapia 2013 Dec 13;91:189-193. Epub 2013 Sep 13.

Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission & Ministry of Education, Yunnan University of Nationalities, Kunming 650031, PR China. Electronic address:

Three new xanthones, 1,5-dihydroxy-3-hydroxyethyl-6-methoxycarbonylxanthone (1), 1-hydroxy-5- methoxy-3-hydroxyethyl-6-methoxycarbonylxanthone (2), and 1-hydroxy-3-hydroxyethyl- 8-ethoxycarbonylxanthone (3), along with seven known xanthones (4-10) were isolated from the fermentation products of an endophytic fungus Phomopsis sp.. Their structures were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques. Compounds 1-10 were also tested for their cytotoxicity against five human tumor cell lines (NB4, A549, SHSY5Y, PC3, and MCF7) by MTT method using paclitaxel as positive control. Compounds 1 and 3 showed cytotoxicity against A549 cell lines with IC50 values of 3.6 and 2.5 μM, respectively. In addition, 1 was cytotoxic to MCF7 cells with IC50 value of 2.7 μM.
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http://dx.doi.org/10.1016/j.fitote.2013.09.004DOI Listing
December 2013

Effect of oxygen free radicals and nitric oxide on apoptosis of immune organ induced by selenium deficiency in chickens.

Biometals 2013 Apr 26;26(2):355-65. Epub 2013 Feb 26.

Department of Veterinary Medicine, Northeast Agricultural University, 59 Mucai street, Harbin, 150030, People's Republic of China.

Selenium is an essential element with antioxidant roles in immune regulation, but there is little understanding of how Se acts in apoptosis in the immune organs of birds. The aim of study was to evaluate the influence of Se deficiency on oxygen free radicals, NO and apoptosis in immune organ of chickens. 160 1-day-old chickens were randomly assigned to two groups of 80 each and were fed on a low-Se diet (0.032 mg/kg Se) or a control diet (0.282 mg/kg Se), respectively. OFR production in blood was determined on days 30, 45, 60 and 75, respectively. The iNOS-NO system activity in immune organ (thymus, spleen, bursa of fabricius) was identified by NO content and NOS activity assay on days 30, 45, 60 and 75, respectively. Apoptosis was measured by DNA ladder analysis, ultrastructural observations, TdT-mediated dUTP nick end labeling TUNEL assay and flow cytometric analysis of apoptotic DNA. The transcription of factor-associated suicide, caspase-3 mRNA was tested by fluorescence quantitative PCR. The results showed that OFR production, NO and inducible NO synthases (iNOS) activity in the low-Se group were significantly increased (p < 0.05) than in the control group. In addition, apoptosis was observed in chicken immune organ in the low-Se group. The degree and the number of apoptotic cells rose in a time-dependent manner. The expression of Fas and caspase-3 mRNA increased (p < 0.05) than in the control group. It indicated that the oxidative stress and NO played a causative role in the apoptosis of immune tissues induced by selenium deficiency.
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http://dx.doi.org/10.1007/s10534-013-9612-8DOI Listing
April 2013

[Analysis of facial far-infrared thermogram of patients with acute facial neuritis].

Zhong Xi Yi Jie He Xue Bao 2011 Nov;9(11):1221-5

Department of Acupuncture and Moxibustion, Chinese PLA General Hospital, Beijing 100853, China.

Objective: In order to provide an objective observational index for facial neuritis, the authors monitored the changes of facial far-infrared thermogram in patients with acute facial neuritis.

Methods: A total of 23 patients with acute facial neuritis were enrolled from Department of Acupuncture and Moxibustion, Chinese PLA General Hospital. Another 21 healthy participants were selected as the control group. Focal plane thermal imaging system (thermal sensitivity 0.05 degrees centigrade) was applied to collect facial far-infrared thermogram. Temperature differences in the thermogram of both sides of the cheeks, inner canthus, supraorbitals and forehead of the same patient were compared separately and statistically and analyzed by software provided by the imaging system.

Results: Results of far-infrared thermography of the patients displayed obvious temperature differences ranging from 0.01 to 0.26 degrees centigrade between two sides of the cheeks, inner canthus, supraorbitals and forehead areas. In the control group, far-infrared thermogram showed that there were no obvious temperature differences between two sides of the cheeks, inner canthus, supraorbitals and forehead. There were significant differences in temperature difference in the four monitoring areas between the two groups (P<0.01). Among the 23 patients, there were 14 patients with congestive change, 7 with ischemic change and 2 with both congestive and ischemic changes.

Conclusion: The facial far-infrared thermogram of patients with acute facial neuritis is characterized mainly by congestive changes. Far-infrared thermography can objectively reflect the changes of blood-supply status in patients with facial neuritis.
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http://dx.doi.org/10.3736/jcim20111110DOI Listing
November 2011

[SEM observation on leaf epidermis of different Ephedra species].

Zhongguo Zhong Yao Za Zhi 2007 Sep;32(18):1854-7

College of Life Sciences & Technology, Gansu Agricultural University, Lanzhou 730070, China.

Objective: Characters of stem epidermis, leaf epidermis and stoma could be used as important microcosmic morphological characteristic when inheritance trend is studied in Ephedra breeding and identification.

Method: The stomatic density, stoma major axis and mimor axis, stomatic morphylogy, characters of leaf and stem epidermis of 6 Ephedra plants' stems were examined by SEM.

Result: The stomatic density and characteristic of leaf epidermis and stem epidermis in six Ephedra species was differenc, there were no obvious morphological differences in stoma shape and size. The guard cells were covered with heavy cuticle and sunken stomata, which were the typical characteristics of xerophytes. The stomas of leaf lower epidermis were oblong or hexagon, but the stomas of steam epidermis were narrowed-oblong or dumbbell-shape, they all belonged to anomalous type.

Conclusion: The stoma type and characters of Ephedra plants is stable and conservative, there was no obvious morphological differences in stoma shape and size between species, so it is difficult to distinguish different species by the variance of stomas, but that can be applyed to distinguish Ephedra from others at plant taxonomy.
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September 2007

[Studies on quantitative structure-retention relationships for sulfides on stationary phases of different polarities].

Se Pu 2002 Sep;20(5):415-8

College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.

Multiple linear regression (MLR) based on forward stepwise multiple regression techniques was used for predicting gas chromatographic retention index of sulfides after calculating their quantum-chemical parameters. The correlative quantitative model between the retention index (IR) of sulfides on four stationary phases of different polarities and their quantum chemical parameters was built. The results proved the strong predictive power of the models. The root-mean-square error (RMS) of the regression equation was less than 4%.
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September 2002

[Sustainment of hepatocyte function with mixed cellular co-encapsulation].

Zhonghua Yi Xue Za Zhi 2005 Sep;85(35):2481-6

Department of Stem Cell Biology, Institute of Transfusion Medicine, Beijing 100850, China.

Objective: To evaluate the effects of mixed microcapsules of hepatocytes mixed with hepatocytes, transgenic hepatic stellate cell strain (HGF/CFSC), and/or bone marrow derived Thy-1(+) beta(2)M(-) cells (BDTCs) to sustain liver function.

Methods: Three kinds of microcapsules containing hepatocytes, hepatocytes + CFSC/HGFs, or hepatocyte + CFSC/HGF + BDTC were prepared and cultured in conditioned culture fluids. The morphology of the microcapsules and the encapsulated cells were observed by microscopy. The supernatant was collected regularly to detect the secretion of albumin and urea. Forty Wistar rats underwent 90% hepatectomization to establish acute liver failure model. Six hours after the operation the rats were randomly divided into 4 groups to be intraperitoneally injected with one of the 3 kinds of microcapsules containing 3.5 x 10(7) hepatocytes as experimental groups (Groups II, III, and IV) or injected with blank microcapsule as control group. The behaviors of the rats were observed daily. Blood was collected from the eyeball at different time points to detect relevant biochemical indicators. Twenty-one and 42 days after the operation the rats were killed. Abdominal lavage was performed to collect the microcapsules to undergo microscopy. Liver specimens were colleted to undergo pathological examination.

Results: Severe liver failure occurred in the rats transplanted with blank microcapsules. Most of the rats in Groups II, III, and IV began to eat within 20 hours after hepatectomization. Nine of the 10 rats in the control group died within 48 hours after hepatectomization. Nine of the 10 rats of Group II survived a long time. All the rats in Groups III and IV survived till the end of experiment. In comparison with the supernatant of Group II, the contents of albumin and urea in the supernatants of Groups III and IV were significantly higher (all P < 0.01). The liver function indicators, ALT, AST, lactic dehydrogenase, and albumin worsened since one day after the operation. Five days after the transplantation of microcapsule, the above indicators showed remarkable improvement, and recovered to normal 7 days after. Twenty-one and 42 days after the transplantation regeneration was seen and edema was reduced in the livers in Groups II, III, and IV. Twenty-one days after the transplantation most of the microcapsules were still free in the peritoneal cavity in Group II. In Group III, most of the microcapsules aggregated around the portal vein, fibrosis at the surface of microcapsule to a certain degree was seen and surviving hepatocytes could be found inside the capsules 21 days after. Forty-two days after, vascularization of microcapsules was seen in Groups III and IV, especially in the latter group.

Conclusion: Mature hepatocyte, transgenic liver nonparenchymal cells and/or BMSCs co-encapsulate transplantation effectively improve acute liver failure. The microenvironment created by CFSC/HGF and/or BDTC is propitious to the maintenance of capsulated hepatocytes' function and longevity.
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September 2005

[Patterns of spasmodic dysphonia and botulinum toxin injections].

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2005 Apr;40(4):253-7

Department of Otorhinolaryngology Head Neck Surgery, Beijing Tongren Hospital, Capital University of Medical Sciences, Beijing 100730, China.

Objective: To investigate the patterns of spasmodic dysphonia and the outcome treated with botulinum toxin A injections.

Methods: All subjects were studied with acoustic analysis, laryngostroboscopy and laryngeal electromyography (EMG) including motor unit potential measure (MUP), recruitment pattern analysis and evoked electromyography. All the patients with spasmodic dysphonia were received botulinum toxin A (BOTOX) injections in each affected muscles and mostly under electromyographic guidance.

Results: Among 22 cases of spasmodic dysphonia, 18 cases of adductor dysphonic patients have strained, strangled voice with intermittent breaks in speech as a consequence of hyperadduction and spasm of the vocal folds during phonation. Two patients had synchronous pharyngeal, lingual and velar tremor. Amplitudes of MUP of thyroarytenoid muscle (TA) were greater in patients group than in normal group (P < 0.01); The recruitment activity was increased and the amplitudes were greater than normal group (700-2500 microV) and the duration of activity of the TA during phonation was also notably greater in patients group than in normal group. Four cases of abductor dysphonic patients have a breathy, effortful hypophonic voice with abrupt termination of voicing. Amplitudes of MUP of posterior cricoarytenoid muscle (PCA) in patients group were increased up to 374 to 538 microV. The recruitment activity was increased and the amplitude was greater than normal(3000-5000 microV). In the adductor dysphonic group, patients who were treated with unilateral toxin injection had good results with 2.5 U or more. The average onset of toxin effect in all adductor dysphonic patients was at 6 hours to 2 days (1.4+/-0. 8) days (x +/- s), with a peak effect at 2 weeks and the follow-up EMG showed fibrillation potentials or electric silence in injected muscle. Duration of benefit was 8 to 24 weeks (15.2 +/- 4.9) weeks. The side-effect of toxin injection were including breathy voice or occasional dysphagia and aspiration. The patients with abductor spasms were less well controlled after PCA injections.

Conclusions: Spasmodic dysphonia was regarded as a neuromuscular diseases, so its diagnosis, classification, treatment and follow-up should depend on not only clinical manifestation but also EMG. Presently, for controlling the dystonic symptoms, the most effective therapy for most of those patients is local BOTOX injections. Repeated injections are required to have a stable results.
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April 2005
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