Publications by authors named "Hong-Wei Dong"

75 Publications

Organization of the inputs and outputs of the mouse superior colliculus.

Nat Commun 2021 06 28;12(1):4004. Epub 2021 Jun 28.

Stevens Neuroimaging and Informatics Institute, Laboratory of Neuro Imaging, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.

The superior colliculus (SC) receives diverse and robust cortical inputs to drive a range of cognitive and sensorimotor behaviors. However, it remains unclear how descending cortical input arising from higher-order associative areas coordinate with SC sensorimotor networks to influence its outputs. Here, we construct a comprehensive map of all cortico-tectal projections and identify four collicular zones with differential cortical inputs: medial (SC.m), centromedial (SC.cm), centrolateral (SC.cl) and lateral (SC.l). Further, we delineate the distinctive brain-wide input/output organization of each collicular zone, assemble multiple parallel cortico-tecto-thalamic subnetworks, and identify the somatotopic map in the SC that displays distinguishable spatial properties from the somatotopic maps in the neocortex and basal ganglia. Finally, we characterize interactions between those cortico-tecto-thalamic and cortico-basal ganglia-thalamic subnetworks. This study provides a structural basis for understanding how SC is involved in integrating different sensory modalities, translating sensory information to motor command, and coordinating different actions in goal-directed behaviors.
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http://dx.doi.org/10.1038/s41467-021-24241-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8239028PMC
June 2021

High Blood Cytomegalovirus Load Suggests Cytomegalovirus Retinitis in HIV/AIDS Patients: A Cross-Sectional Study.

Ocul Immunol Inflamm 2021 Jun 14:1-5. Epub 2021 Jun 14.

Beijing Tongren Eye Center, Beijing Key Laboratory of Intraocular Tumor Diagnosis and Treatment, Beijing Ophthalmology and Visual Sciences Key Lab, Beijing Tongren Hospital, Capital Medical University, Beijing, China.

: To clarify the cut off value of blood CMV load to indicate CMV retinitis and its relationships with ocular features. Patients were divided into non-CMV and CMV retinitis groups. A logistic regression model was applied to estimate the association of each variable with CMV retinitis. Spearman correlation was used to estimate the correlation between the blood and aqueous CMV load. Blood CMV load higher than 4log (OR, 6.897; CI: 2.813-16.910; < .001) was the major predictor of CMV retinitis. Blood CMV load wasn't different between the initial and early stage ( = .066). No correlation was observed between the blood and aqueous CMV load ( = .083, r = 0.228). Blood CMV load higher than 4log is an important predictor for CMV retinitis in HIV/AIDS patients, but it couldn't indicate the ocular features. Ophthalmologic screening is still necessary.: CMV: Cytomegalovirus; CMVR: Cytomegalovirus retinitis; HIV: Human Immunodeficiency Virus; AIDS: Acquired Immune Deficiency Syndrome; ART: Antiretroviral therapy; EOD: End-organ diseases; PCR: Polymerase Chain Reaction; OR: Odds Ratio; CI: 95% Confidence Interval; IQR: Interquartile range.
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http://dx.doi.org/10.1080/09273948.2021.1905857DOI Listing
June 2021

Clinical efficacy of laser therapy in the prevention of retinal detachment in patients with acquired immunodeficiency syndrome and cytomegalovirus retinitis.

Quant Imaging Med Surg 2021 Jun;11(6):2634-2641

Beijing Tongren Eye Center, Beijing Key Laboratory of Intraocular Tumor Diagnosis and Treatment, Beijing Ophthalmology & Visual Sciences Key Lab, Medical Artificial Intelligence Research and Verification Key Laboratory of the Ministry of Industry and Information Technology, Beijing Tongren Hospital, Capital Medical University, Beijing, China.

Background: The aim of the present study was to evaluate the clinical efficacy of laser therapy in the prevention of retinal detachment in patients with acquired immunodeficiency syndrome (AIDS) and cytomegalovirus retinitis (CMVR).

Methods: A total of 96 eyes from 80 patients with AIDS and CMVR who received anticytomegalovirus (anti-CMV) treatment in the ophthalmology and infection centers of Beijing YouAn Hospital, between June 2016 and August 2018 were retrospectively investigated. The patients were randomly divided into a nonlaser group (50 eyes from 43 patients), who were treated with anti-CMV therapy, and a laser group (46 eyes from 37 patients), who were treated with a fundus laser method to close the retinopathy area after commencing the maintenance stage of anti-CMV treatment. Both groups were followed up for 24 months. The safety of laser therapy was observed, and the efficacy of the therapy was determined by evaluating the incidence of retinal detachment.

Results: The percentage of retinal detachment in the nonlaser group was 24% compared with 6.5% in the laser group (P=0.018). There was no significant difference between the two groups in the number of CD4 T cells, the load of human immunodeficiency virus, or the time between the detachment and the end of the induction period. After laser therapy, 39.13% of patients exhibited keratic precipitates (KP), 30.43% had anterior chamber flare (±), 50% had anterior chamber flare (+), and 19.57% had anterior chamber flare (++). Intraocular pressure (IOP) increased in 3 eyes within 2 weeks of laser therapy. The retinal pigment reaction was not obvious in 8 eyes.

Conclusions: The use of laser therapy in the main maintenance period of anti-CMV treatment can effectively reduce the incidence of retinal detachment in patients with AIDS and CMVR, and the therapy is safe and reliable.
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http://dx.doi.org/10.21037/qims-20-990DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8107343PMC
June 2021

Clinical Features of Ocular Pathology in Patients with Acquired Immunodeficiency Syndrome and Syphilis.

Adv Ther 2021 06 21;38(6):3362-3372. Epub 2021 May 21.

Beijing Tongren Eye Center, Beijing key Laboratory of Intraocular Tumor Diagnosis and Treatment, Beijing Ophthalmology and Visual Sciences Key Lab, Medical Artificial Intelligence Research and Verification Key Laboratory of the Ministry of Industry and Information Technology, Beijing Tongren Hospital, Capital Medical University, No.1 Dongjiaomin Lane, Dongcheng District, Beijing, 100730, China.

Introduction: The present study aimed to analyze the clinical features of ocular pathology in patients with acquired immunodeficiency syndrome (AIDS) combined with syphilis.

Methods: A total of 129 patients with AIDS and syphilis who first visited the Department of Ophthalmology in Beijing YouAn Hospital between 2012 and 2019 were included in the study. All patients underwent ophthalmologic examinations, such as best-corrected visual acuity (BCVA), slit lamp, intraocular pressure, dilated fundus examination, and color fundus photography as well as systemic examinations related to AIDS and syphilis. The patients were divided into four groups according to fundus disease: a normal fundi group, an HIV-related microvascular retinopathy (MVR) group, a cytomegalovirus retinitis (CMVR) group, and a syphilis-related retinopathy group.

Results: The incidence of fundus disease was 70.7%. There were 36 patients with normal fundi (29.3%), 40 with HIV-related MVR (31.0%), 25 with CMVR (19.4%) (including 11 cases of CMVR with syphilis-related retinopathy), 26 (20.2%) with syphilis-related retinopathy, 1 (0.78%) case with acute retinal necrosis, and 1 (0.78%) case with PORN. The median blood CD4 + T-cell count in the syphilis-associated retinopathy group was 357.5 cells/μl, which was significantly higher than in the other groups; this difference was statistically significant. In the CMVR group, 11 cases with concomitant syphilis-associated retinopathy had lower BCVA and 10 (90.9%) had active inflammatory manifestations in the anterior segment.

Conclusion: The incidence of ocular pathology was high in patients co-infected with AIDS and syphilis, which might manifest in a variety of ocular manifestations; some patients may also have multiple ocular changes, which should be given great clinical attention.
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http://dx.doi.org/10.1007/s12325-021-01755-1DOI Listing
June 2021

Connectivity characterization of the mouse basolateral amygdalar complex.

Nat Commun 2021 05 17;12(1):2859. Epub 2021 May 17.

Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA.

The basolateral amygdalar complex (BLA) is implicated in behaviors ranging from fear acquisition to addiction. Optogenetic methods have enabled the association of circuit-specific functions to uniquely connected BLA cell types. Thus, a systematic and detailed connectivity profile of BLA projection neurons to inform granular, cell type-specific interrogations is warranted. Here, we apply machine-learning based computational and informatics analysis techniques to the results of circuit-tracing experiments to create a foundational, comprehensive BLA connectivity map. The analyses identify three distinct domains within the anterior BLA (BLAa) that house target-specific projection neurons with distinguishable morphological features. We identify brain-wide targets of projection neurons in the three BLAa domains, as well as in the posterior BLA, ventral BLA, posterior basomedial, and lateral amygdalar nuclei. Inputs to each nucleus also are identified via retrograde tracing. The data suggests that connectionally unique, domain-specific BLAa neurons are associated with distinct behavior networks.
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http://dx.doi.org/10.1038/s41467-021-22915-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8129205PMC
May 2021

Effect of Anti-CMV Therapy at Different Stages on Retinal Detachment in Patients with AIDS and CMVR.

Adv Ther 2021 05 17;38(5):2294-2301. Epub 2021 Mar 17.

Beijing Tongren Eye Center, Beijing Key Laboratory of Intraocular Tumor Diagnosis and Treatment, Beijing Ophthalmology and Visual Sciences Key Lab, Medical Artificial Intelligence Research and Verification Key Laboratory of the Ministry of Industry and Information Technology, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China.

Introduction: The present study aimed to investigate the effect of anti-cytomegalovirus (anti-CMV) therapy at different stages on retinal detachment in patients with acquired immunodeficiency syndrome (AIDS) and cytomegalovirus retinitis (CMVR).

Methods: Ninety-seven patients with AIDS and CMVR diagnosed and treated at the Ophthalmology and Infection Center of Beijing You'an Hospital, affiliated with Capital Medical University, from November 2017 to January 2020 were retrospectively analyzed. Of the 138 eyes included, 30 eyes with concomitant retinal detachment were enrolled as the study subjects. The eyes with retinal detachment were divided into a pre-induction group, an intra-induction group, and a post-induction group of anti-CMV therapy. The occurrence and characteristics of retinal detachment at different stages of anti-CMV therapy were observed.

Results: Retinal detachment occurred in 30 of the 138 eyes of 97 patients, with an incidence of retinal detachment of 21.74%. Retinal detachment occurred in eight eyes in the pre-induction group, with an incidence of 26.67%, and in four eyes in the intra-induction group, with an incidence of 13.33%. The difference in incidence between the two groups was statistically significant (P = 0.000). Retinal detachment occurred in 18 eyes in the post-induction group, with an incidence of 60%. The difference in incidence between the intra-induction group and the post-induction group was statistically significant (P = 0.001).

Conclusion: The incidence of retinal detachment at the intra-induction stages of anti-CMV therapy was lower than that at the pre-induction stage, and retinal detachment during the anti-CMV therapy predominantly occurred after the end of the induction stage.
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http://dx.doi.org/10.1007/s12325-021-01674-1DOI Listing
May 2021

Homologous laminar organization of the mouse and human subiculum.

Sci Rep 2021 Feb 12;11(1):3729. Epub 2021 Feb 12.

USC Stevens Neuroimaging and Informatics Institute, Laboratory of Neuro Imaging (LONI), Keck School of Medicine of University of Southern California, Los Angeles, CA, 90033, USA.

The subiculum is the major output component of the hippocampal formation and one of the major brain structures most affected by Alzheimer's disease. Our previous work revealed a hidden laminar architecture within the mouse subiculum. However, the rotation of the hippocampal longitudinal axis across species makes it unclear how the laminar organization is represented in human subiculum. Using in situ hybridization data from the Allen Human Brain Atlas, we demonstrate that the human subiculum also contains complementary laminar gene expression patterns similar to the mouse. In addition, we provide evidence that the molecular domain boundaries in human subiculum correspond to microstructural differences observed in high resolution MRI and fiber density imaging. Finally, we show both similarities and differences in the gene expression profile of subiculum pyramidal cells within homologous lamina. Overall, we present a new 3D model of the anatomical organization of human subiculum and its evolution from the mouse.
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http://dx.doi.org/10.1038/s41598-021-81362-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7881248PMC
February 2021

Utility of Ultra-Wide-Field Imaging for Screening of AIDS-Related Cytomegalovirus Retinitis.

Ophthalmologica 2020 Oct 29. Epub 2020 Oct 29.

Purpose: To explore the potential use of ultra-wide-field (UWF) imaging for screening of cytomegalovirus retinitis (CMVR) in AIDS patients.

Methods: Ninety-four patients whose CD4 count was below 200 cells/μl were enrolled in a prospective study. Each patient underwent UWF imaging and indirect ophthalmoscopy. The main outcome measures were the concordance and detection rates of these two approaches and the sensitivity and specificity of UWF imaging.

Results: Twenty-seven eyes in 18 patients were diagnosed with CMVR by the indirect ophthalmoscopy. UWF imaging missed the diagnosis in one eye because of a zone 3 CMVR lesion. The UWF image showed several CMVR patterns and locations: hemorrhagic necrotizing lesion, granular lesion, frosted branch angiitis, and optic neuropathy lesion. The concordance of the two approaches was excellent for diagnosis of CMVR, classification of CMVR pattern, and location of CMVR. The detection rates of UWF imaging and indirect ophthalmoscopy were 14.0% (26/186; 95% CI, 0.089-0.190) and 14.5% (27/186; 95% CI, 0.094-0.196), respectively (p = 1.000). The sensitivity and specificity of UWF imaging were 96.3% and 100%, respectively.

Conclusions: UWF imaging is capable of documentation of different CMVR lesions and AIDS-related CMVR screening when examination by an ophthalmologist is not available.
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http://dx.doi.org/10.1159/000512634DOI Listing
October 2020

Detection of neurophysiological features in female R255X MeCP2 mutation mice.

Neurobiol Dis 2020 11 12;145:105083. Epub 2020 Sep 12.

Department of Pediatrics, Division of Neurology, Vanderbilt University Medical Center, Nashville, TN 37212, USA; Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN 37203, USA. Electronic address:

Rett syndrome (RTT) is a severe neurodevelopmental disorder (NDD) that is nearly always caused by loss of function mutations in Methyl-CpG-binding Protein 2 (MECP2) and shares many clinical features with other NDD. Genetic restoration of Mecp2 in symptomatic mice lacking MeCP2 expression can reverse symptoms, providing hope that disease modifying therapies can be identified for RTT. Effective and rapid clinical trial completion relies on well-defined clinical outcome measures and robust biomarkers of treatment responses. Studies on other NDD have found evidence of differences in neurophysiological measures that correlate with disease severity. However, currently there are no well-validated biomarkers in RTT to predict disease prognosis or treatment responses. To address this, we characterized neurophysiological features in a mouse model of RTT containing a knock-in nonsense mutation (p.R255X) in the Mecp2 locus. We found a variety of changes in heterozygous female Mecp2 mice including age-related changes in sleep/wake architecture, alterations in baseline EEG power, increased incidence of spontaneous epileptiform discharges, and changes in auditory evoked potentials. Furthermore, we identified association of some neurophysiological features with disease severity. These findings provide a set of potential non-invasive and translatable biomarkers that can be utilized in preclinical therapy trials in animal models of RTT and eventually within the context of clinical trials.
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http://dx.doi.org/10.1016/j.nbd.2020.105083DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7572861PMC
November 2020

Brainwide Genetic Sparse Cell Labeling to Illuminate the Morphology of Neurons and Glia with Cre-Dependent MORF Mice.

Neuron 2020 10 13;108(1):111-127.e6. Epub 2020 Aug 13.

Center for Neurobehavioral Genetics, Jane and Terry Semel Institute for Neuroscience and Human Behavior, and Department of Psychiatry and Biobehavioral Sciences, Brain Research Institute, David Geffen School of Medicine at University of California, Los Angeles, Los Angeles, CA 90095, USA. Electronic address:

Cajal recognized that the elaborate shape of neurons is fundamental to their function in the brain. However, there are no simple and generalizable genetic methods to study neuronal or glial cell morphology in the mammalian brain. Here, we describe four mouse lines conferring Cre-dependent sparse cell labeling based on mononucleotide repeat frameshift (MORF) as a stochastic translational switch. Notably, the optimized MORF3 mice, with a membrane-bound multivalent immunoreporter, confer Cre-dependent sparse and bright labeling of thousands of neurons, astrocytes, or microglia in each brain, revealing their intricate morphologies. MORF3 mice are compatible with imaging in tissue-cleared thick brain sections and with immuno-EM. An analysis of 151 MORF3-labeled developing retinal horizontal cells reveals novel morphological cell clusters and axonal maturation patterns. Our study demonstrates a conceptually novel, simple, generalizable, and scalable mouse genetic solution to sparsely label and illuminate the morphology of genetically defined neurons and glia in the mammalian brain.
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http://dx.doi.org/10.1016/j.neuron.2020.07.019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7572760PMC
October 2020

An open access mouse brain flatmap and upgraded rat and human brain flatmaps based on current reference atlases.

J Comp Neurol 2021 02 19;529(3):576-594. Epub 2020 Jul 19.

Center for Integrated Connectomics (CIC), Keck School of Medicine of University of Southern California, University of Southern California Stevens Neuroimaging and Informatics Institute, Los Angeles, California, USA.

Here we present a flatmap of the mouse central nervous system (CNS) (brain) and substantially enhanced flatmaps of the rat and human brain. Also included are enhanced representations of nervous system white matter tracts, ganglia, and nerves, and an enhanced series of 10 flatmaps showing different stages of rat brain development. The adult mouse and rat brain flatmaps provide layered diagrammatic representation of CNS divisions, according to their arrangement in corresponding reference atlases: Brain Maps 4.0 (BM4, rat) (Swanson, The Journal of Comparative Neurology, 2018, 526, 935-943), and the first version of the Allen Reference Atlas (mouse) (Dong, The Allen reference atlas, (book + CD-ROM): A digital color brain atlas of the C57BL/6J male mouse, 2007). To facilitate comparative analysis, both flatmaps are scaled equally, and the divisional hierarchy of gray matter follows a topographic arrangement used in BM4. Also included with the mouse and rat brain flatmaps are cerebral cortex atlas level contours based on the reference atlases, and direct graphical and tabular comparison of regional parcellation. To encourage use of the brain flatmaps, they were designed and organized, with supporting reference tables, for ease-of-use and to be amenable to computational applications. We demonstrate how they can be adapted to represent novel parcellations resulting from experimental data, and we provide a proof-of-concept for how they could form the basis of a web-based graphical data viewer and analysis platform. The mouse, rat, and human brain flatmap vector graphics files (Adobe Reader/Acrobat viewable and Adobe Illustrator editable) and supporting tables are provided open access; they constitute a broadly applicable neuroscience toolbox resource for researchers seeking to map and perform comparative analysis of brain data.
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http://dx.doi.org/10.1002/cne.24966DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7721992PMC
February 2021

Beta-ionone-inhibited proliferation of breast cancer cells by inhibited COX-2 activity.

Arch Toxicol 2019 10 10;93(10):2993-3003. Epub 2019 Sep 10.

Department of Clinical Laboratory, The Forth Affiliated Hospital of Harbin Medical University, 37 YiYuan Street, NanGang District, Harbin, 150001, People's Republic of China.

As one of the isoprenoids and widely derived from many fruits and vegetables, β-ionone (BI) has a potent inhibitory proliferation of cancer cells in vitro and in vivo. However, its exact mechanism is still uncompleted understood and needs to be further verified. Cyclooxygenase-2 (COX-2), as a potential target of cancer chemoprevention, has been played pivotal roles in proliferation of tumor cells and carcinogenesis. Thus, the objective of present study was to determine that BI inhibited the activity of COX-2 in breast cancer and related to cancer cell models. Cell proliferation, DNA synthesis, the distribution of cell cycle, apoptosis induction and the expression of P38-MAPK protein were determined in MCF-7 cells by methylene blue, H-thymidine (TdR) incorporation, flow cytometry, TUNEL and Western blotting assays. Quinone reductase (QR) activity was determined in murine hepatoma Hepa1c1c7 cells by enzyme-linked immunosorbent assay (ELISA). The expression of COX-2 in a phorbol-12-myristate-13-acetate (PMA)-induced cell model and mammary tumor tissues was examined by Western blotting and immunohistochemistry. The results showed that BI significantly inhibited cell proliferation and DNA synthesis, arrested the distribution of cell cycle at the S phase or decreased proteins related to cell cycle such as cyclin D1 and CDK4, induced apoptosis and increased the expression of p-P38 in MCF-7 cells. BI at low doses (< 50 μmol/L) significantly increased QR activity, decreased the expression of COX-2 protein and prostaglandin E2 (PEG2) release in cell models. In addition, BI also significantly decreased the expression of COX-2 protein in rat mammary tumor tissues. Therefore, our findings indicate that BI possesses inhibitory proliferation of breast cancer cells through down-regulation of COX-2 activity.
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http://dx.doi.org/10.1007/s00204-019-02550-2DOI Listing
October 2019

Effect of individualized therapy for AIDS patients with cytomegalovirus retinitis in intravitreal ganciclovir injections.

Int J Ophthalmol 2019 18;12(8):1351-1355. Epub 2019 Aug 18.

Beijing Tongren Eye Center, Beijing Key Laboratory of Intraocular Tumor Diagnosis and Treatment, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing Tong Ren Hospital, Capital Medical University, Beijing 100730, China.

The effect of intravitreal ganciclovir injection combined with intravenous infusion on acquired immune deficiency syndrome (AIDS) patients with cytomegalovirus retinitis (CMVR) was investigated. A total of 32 eyes in 23 AIDS patients diagnosed as CMVR from 2017 to 2018 were included in the retrospective study. All patients underwent induction therapy by using intravenous drip of the anti-cytomegalovirus (CMV) agent ganciclovir (5 mg/kg ) combined with intravitreal ganciclovir injection (3 mg/time, 2 times/wk). The visual acuity, fundus photographs, lesion location, and number of intravitreal injections were observed preoperatively and postoperatively. Totally 14 eyes were cured during induction therapy. The number of injections [4.13 (2 to 6)] in CMVR patients with peripherally fundus lesions were significantly lower than those with central lesions [4.89 (2 to 6)]. The individualized therapy of intravitreal ganciclovir injections for AIDS patients with CMVR can effectively reduce the numbers of intravitreal injections.
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http://dx.doi.org/10.18240/ijo.2019.08.19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6694063PMC
August 2019

Reproductive toxicity of perchlorate in rats.

Food Chem Toxicol 2019 Jun 13;128:212-222. Epub 2019 Apr 13.

Harbin Medical University Library, 194 XueFu Road, NanGang District, Harbin, 150081, People's Republic of China. Electronic address:

Perchlorate, as an oxidizer, has many applications such as explosives and pyrotechnics, especially in rocket propellants and missile motors. Because it was found in water including wells and drinking water in the US, its effect on human health was being noted. However, the reproductive toxic effect on perchlorate is still unclear. In present study, the effects of repeated exposure to perchlorate on reproductive toxicity were evaluated in Wistar rats. The rats were treated orally with perchlorate at doses of 0.05, 1.00 or 10.00 mg/kg body weight (b.w.) daily for 8 weeks. The levels of T and T hormones in the rat serum were detected by radioimmunoassay kit. The indexes of reproduction, percentage of organ in body weight (%) and frequency of abnormal sperm cells were also analyzed in this study. DNA damage in testicular cells was evaluated by Comet assay. The levels of MDA, GSH and SOD were examined in testicle tissues of rats by ELISA. The expression of c-fos and fas protein was examined in testicle tissues by immunohistochemistry. The results showed that perchlorate did not affect the body weight of rats. Perchlorate also significantly decreased indexes of live birth and weaning in the groups of 1.00 and 10.00 mg/kg, and viability index only in the 10.00 mg/kg group (P < 0.05). Perchlorate also significantly decreased the serum level of T in male rats of 1.00 and 10.00 mg/kg groups, increased the rate of sperm abnormality (10.00 mg/kg), potentially caused DNA damage in testicular cells and altered the status of oxidative stress in male rats. In addition, because of the increase in the expression of fas and c-fos protein in testicle tissues, perchlorate could induce apoptosis in spermatogenesis. Thus, these findings indicate that perchlorate could cause DNA damage in testicular tissues and reduce testicular spermatogenic ability, resulting in reproductive toxicity.
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http://dx.doi.org/10.1016/j.fct.2019.04.014DOI Listing
June 2019

Precise segmentation of densely interweaving neuron clusters using G-Cut.

Nat Commun 2019 04 4;10(1):1549. Epub 2019 Apr 4.

Center for Integrative Connectomics, USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, 90095, USA.

Characterizing the precise three-dimensional morphology and anatomical context of neurons is crucial for neuronal cell type classification and circuitry mapping. Recent advances in tissue clearing techniques and microscopy make it possible to obtain image stacks of intact, interweaving neuron clusters in brain tissues. As most current 3D neuronal morphology reconstruction methods are only applicable to single neurons, it remains challenging to reconstruct these clusters digitally. To advance the state of the art beyond these challenges, we propose a fast and robust method named G-Cut that is able to automatically segment individual neurons from an interweaving neuron cluster. Across various densely interconnected neuron clusters, G-Cut achieves significantly higher accuracies than other state-of-the-art algorithms. G-Cut is intended as a robust component in a high throughput informatics pipeline for large-scale brain mapping projects.
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http://dx.doi.org/10.1038/s41467-019-09515-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6449501PMC
April 2019

Extrastriate connectivity of the mouse dorsal lateral geniculate thalamic nucleus.

J Comp Neurol 2019 05 4;527(9):1419-1442. Epub 2019 Feb 4.

USC Stevens Neuroimaging and Informatics Institute, Center for Integrative Connectomics, Keck School of Medicine of University of Southern California, Los Angeles, California.

The mammalian visual system is one of the most well-studied brain systems. Visual information from the retina is relayed to the dorsal lateral geniculate nucleus of the thalamus (LGd). The LGd then projects topographically to primary visual cortex (VISp) to mediate visual perception. In this view, the VISp is a critical network hub where visual information must traverse LGd-VISp circuits to reach higher order "extrastriate" visual cortices, which surround the VISp on its medial and lateral borders. However, decades of conflicting reports in a variety of mammals support or refute the existence of extrastriate LGd connections that can bypass the VISp. Here, we provide evidence of bidirectional extrastriate connectivity with the mouse LGd. Using small, discrete coinjections of anterograde and retrograde tracers within the thalamus and cortex, our cross-validated approach identified bidirectional connectivity between LGd and extrastriate visual cortices. We find robust reciprocal connectivity of the medial extrastriate regions with LGd neurons distributed along the "ventral strip" border with the intergeniculate leaflet. In contrast, LGd input to lateral extrastriate regions is sparse, but lateral extrastriate regions return stronger descending projections to localized LGd areas. We show further evidence that axons from lateral extrastriate regions can overlap onto medial extrastriate-projecting LGd neurons in the ventral strip, providing a putative subcortical LGd pathway for communication between medial and lateral extrastriate regions. Overall, our findings support the existence of extrastriate LGd circuits and provide novel understanding of LGd organization in rodent visual system.
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http://dx.doi.org/10.1002/cne.24627DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6992387PMC
May 2019

Integration of gene expression and brain-wide connectivity reveals the multiscale organization of mouse hippocampal networks.

Nat Neurosci 2018 11 8;21(11):1628-1643. Epub 2018 Oct 8.

University of Southern California Stevens Neuroimaging and Informatics Institute, Center for Integrated Connectomics (CIC), Keck School of Medicine of University of Southern California, Los Angeles, CA, USA.

Understanding the organization of the hippocampus is fundamental to understanding brain function related to learning, memory, emotions, and diseases such as Alzheimer's disease. Physiological studies in humans and rodents have suggested that there is both structural and functional heterogeneity along the longitudinal axis of the hippocampus. However, the recent discovery of discrete gene expression domains in the mouse hippocampus has provided the opportunity to re-evaluate hippocampal connectivity. To integrate mouse hippocampal gene expression and connectivity, we mapped the distribution of distinct gene expression patterns in mouse hippocampus and subiculum to create the Hippocampus Gene Expression Atlas (HGEA). Notably, previously unknown subiculum gene expression patterns revealed a hidden laminar organization. Guided by the HGEA, we constructed the most detailed hippocampal connectome available using Mouse Connectome Project ( http://www.mouseconnectome.org ) tract tracing data. Our results define the hippocampus' multiscale network organization and elucidate each subnetwork's unique brain-wide connectivity patterns.
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http://dx.doi.org/10.1038/s41593-018-0241-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6398347PMC
November 2018

Input-output organization of the mouse claustrum.

J Comp Neurol 2018 10 25;526(15):2428-2443. Epub 2018 Sep 25.

Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, California.

Progress in determining the precise organization and function of the claustrum (CLA) has been hindered by the difficulty in reliably targeting these neurons. To overcome this, we used a projection-based targeting strategy to selectively label CLA principal neurons. Combined with adeno-associated virus (AAV) and monosynaptic rabies tracing techniques, we systematically examined the pre-synaptic input and axonal output of this structure. We found that CLA neurons projecting to retrosplenial cortex (RSP) collateralize extensively to innervate a variety of higher-order cortical regions. No subcortical labeling was found, with the exception of sparse terminals in the basolateral amygdala (BLA). This pattern of output was similar to cingulate- and visual cortex-projecting CLA neurons, suggesting a common targeting scheme among these projection-defined populations. Rabies virus tracing directly demonstrated widespread synaptic inputs to RSP-projecting CLA neurons from both cortical and subcortical areas. The strongest inputs arose from classically defined limbic regions, including medial prefrontal cortex, anterior cingulate, BLA, ventral hippocampus, and neuromodulatory systems such as the dorsal raphe and cholinergic basal forebrain. These results suggest that the CLA may integrate information related to the emotional salience of stimuli and may globally modulate cortical state by broadcasting its output uniformly across a variety of higher cognitive centers.
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http://dx.doi.org/10.1002/cne.24502DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6196111PMC
October 2018

Activation of Group II Metabotropic Glutamate Receptors Suppresses Excitability of Mouse Main Olfactory Bulb External Tufted and Mitral Cells.

Front Cell Neurosci 2017 17;11:436. Epub 2018 Jan 17.

Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, United States.

Metabotropic glutamate receptors (mGluRs) are abundantly expressed in the rodent main olfactory bulb. The function of Group I mGluRs has been investigated in a number of studies, while the actions of Group II mGluRs, which include the mGluR2 and mGluR3 subtypes, have been less well explored. Here, we used electrophysiological approaches in mouse olfactory bulb slices to investigate how Group II mGluR activation and inactivation modifies the activity of external tufted (ET) and mitral cells. The Group II mGluR agonist DCG-IV was found to directly and uniformly reduce the spontaneous discharge of ET and mitral cells. The inhibitory effect of DCG-IV was absent in mitral cells with truncated apical dendrites, indicating a glomerular site of action. DCG-IV did not influence olfactory nerve-evoked monosynaptic responses in ET or mitral cells, indicating that Group II mGluRs do not presynaptically modulate glutamate release from olfactory nerve terminals. In contrast, DCG-IV suppressed polysynaptic responses in periglomerular cells evoked by olfactory nerve stimulation. DCG-IV also inhibited glutamate release from ET cells, and suppressed the spontaneous and olfactory nerve-evoked long-lasting depolarization in mitral cells. Applied alone, Group II receptor antagonists were without effect, suggesting that basal activation of these receptors is nil. These findings suggest that Group II mGluRs inhibit ET and mitral cell activity and further dampen intraglomerular excitatory circuits by suppressing glutamate release.
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http://dx.doi.org/10.3389/fncel.2017.00436DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5776129PMC
January 2018

Comparative analysis of cytomegalovirus retinitis and microvascular retinopathy in patients with acquired immunodeficiency syndrome.

Int J Ophthalmol 2017 18;10(9):1396-1401. Epub 2017 Sep 18.

Beijing Tongren Eye Center, Beijing Key Laboratory of Intraocular Tumor Diagnosis and Treatment, Beijing Ophthalmology and Visual Sciences Key Lab, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.

Aim: To compare the clinical manifestation of cytomegalovirus (CMV) retinitis and microvascular retinopathy (MVR) in patients with acquired immunodeficiency syndrome (AIDS) in China.

Methods: A total of 93 consecutive patients with AIDS, including 41 cases of CMV retinitis and 52 cases of MVR were retrospectively reviewed. Highly active antiretroviral therapy (HAART) status was recorded. HIV and CMV immunoassay were also tested. CD4+ T-lymphocyte count and blood CMV-DNA test were performed in all patients. Aqueous humor CMV-DNA test was completed in 39 patients. Ophthalmological examinations including best corrected visual acuity (BCVA, by International Standard Vision Chart), intraocular pressure (IOP), slit-lamp biomicroscopy, indirect ophthalmoscopy were performed.

Results: In MVR group, the anterior segment examination was normal in all patients with a mean BCVA of 0.93±0.13. Blood CMV-DNA was 0 (0, 269 000) and 42 patients (80.77%) did not receive HAART. In CMV retinitis group, 13 patients (31.71%) had anterior segment abnormality. The mean BCVA was 0.64±0.35 and blood CMV-DNA was 3470 (0, 1 450 000). Nineteen patients (46.34%) had not received HAART. MVR group and CMV retinitis group the positive rates of aqueous CMV-DNA were 0 and 50%, respectively. Two patients with MVR progressed to CMV retinitis during the follow-up period.

Conclusion: In comparison of CMV, patients with MVR have relatively mild visual function impairment. Careful ophthalmological examination and close follow-up are mandatory, especially for patients who have systemic complications, positive CMV-DNA test and without received HAART.
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http://dx.doi.org/10.18240/ijo.2017.09.11DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5596225PMC
September 2017

[Nitrous Oxide Emissions and Its Influencing Factors from an Agricultural Headwater Ditch During a Maize Season in the Hilly Area of Central Sichuan Basin].

Huan Jing Ke Xue 2017 May;38(5):2074-2083

Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China.

Agricultural headwater ditches, the important locations for retaining and transforming nitrogen derived from the adjacent farmlands, have been regarded as the potential source of nitrous oxide (NO) emission. In this study, NO emissions from a typical agricultural ditch in the Hilly Area of Central Sichuan Basin, were observed by closed static chamber-GC technique during the maize season (rainy season), from June to the end of September. During the study period, cumulative NO emissions in the sediment-water interface without vegetation (NV) and the ditch ecosystem with natural vegetation (V) were 0.07 and 0.43 kg·hm, respectively. Meanwhile, the mean NO flux from the agricultural headwater ditch ecosystem[14.7 μg·(m·h)] was comparable to the magnitude of direct NO flux from the maize cropland in this region. Nitrate concentration in the overlying water could be the main factor governing NO emission from the ditch, especially in the rainy season. The existence of vegetation increased the indirect NO emission factor (V:0.05% .NV:0.01%). The indirect NO emission factor from this field investigation was much lower than the default value proposed by the Intergovernmental Panel on Climate Change (IPCC, 2006) for assessing indirect agricultural NO emissions. More attention should be paid to measurements to reduce uncertainty of NO estimation calculated by only applying the default value for emission factor from the IPCC.
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http://dx.doi.org/10.13227/j.hjkx.201611163DOI Listing
May 2017

Aniline Induces Oxidative Stress and Apoptosis of Primary Cultured Hepatocytes.

Int J Environ Res Public Health 2016 11 30;13(12). Epub 2016 Nov 30.

Department of Occupational Health, College of Public Health, Harbin Medical University, Harbin 150086, China.

The toxicity and carcinogenicity of aniline in humans and animals have been well documented. However, the molecular mechanism involved in aniline-induced liver toxicity and carcinogenesis remains unclear. In our research, primary cultured hepatocytes were exposed to aniline (0, 1.25, 2.50, 5.0 and 10.0 μg/mL) for 24 h in the presence or absence of -acetyl-l-cysteine (NAC). Levels of reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH), activities of superoxide dismutase (SOD) and catalase (CAT), mitochondrial membrane potential, DNA damage, cell viability, and apoptosis were detected. Levels of ROS and MDA were significantly increased and levels of GSH and CAT, activity of SOD, and mitochondrial membrane potential in hepatocytes were significantly decreased by aniline compared with the negative control group. The tail moment and DNA content of the tail in exposed groups were significantly higher than those in the negative control group. Cell viability was reduced and apoptotic death was induced by aniline in a concentration-dependent manner. The phenomena of ROS generation, oxidative damage, loss of mitochondrial membrane potential, DNA damage and apoptosis could be prevented if ROS inhibitor NAC was added. ROS generation is involved in the loss of mitochondrial membrane potential and DNA injury, which may play a role in aniline-induced apoptosis in hepatocytes. Our study provides insight into the mechanism of aniline-induced toxicity and apoptosis of hepatocytes.
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http://dx.doi.org/10.3390/ijerph13121188DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5201329PMC
November 2016

Activation of β-noradrenergic receptors enhances rhythmic bursting in mouse olfactory bulb external tufted cells.

J Neurophysiol 2016 12 14;116(6):2604-2614. Epub 2016 Sep 14.

Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, Tennessee.

The main olfactory bulb (MOB) receives a rich noradrenergic innervation from the nucleus locus coeruleus. Despite the well-documented role of norepinephrine and β-adrenergic receptors in neonatal odor preference learning, identified cellular physiological actions of β-receptors in the MOB have remained elusive. β-Receptors are expressed at relatively high levels in the MOB glomeruli, the location of external tufted (ET) cells that exert an excitatory drive on mitral and other cell types. The present study investigated the effects of β-receptor activation on the excitability of ET cells with patch-clamp electrophysiology in mature mouse MOB slices. Isoproterenol and selective β-, but not β-, receptor agonists were found to enhance two key intrinsic currents involved in ET burst initiation: persistent sodium (I) and hyperpolarization-activated inward (I) currents. Together, the positive modulation of these currents increased the frequency and strength of ET cell rhythmic bursting. Rodent sniff frequency and locus coeruleus neuronal firing increase in response to novel stimuli or environments. The increase in ET excitability by β-receptor activation may better enable ET cell rhythmic bursting, and hence glomerular network activity, to pace faster sniff rates during heightened norepinephrine release associated with arousal.
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http://dx.doi.org/10.1152/jn.00034.2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5133314PMC
December 2016

The mouse cortico-striatal projectome.

Nat Neurosci 2016 08 20;19(8):1100-14. Epub 2016 Jun 20.

USC Stevens Neuroimaging and Informatics Institute, Laboratory of Neuro Imaging (LONI), Keck School of Medicine of University of Southern California, Los Angeles, California, USA.

Different cortical areas are organized into distinct intracortical subnetworks. The manner in which descending pathways from the entire cortex interact subcortically as a network remains unclear. We developed an open-access comprehensive mesoscale mouse cortico-striatal projectome: a detailed connectivity projection map from the entire cerebral cortex to the dorsal striatum or caudoputamen (CP) in rodents. On the basis of these projections, we used new computational neuroanatomical tools to identify 29 distinct functional striatal domains. Furthermore, we characterized different cortico-striatal networks and how they reconfigure across the rostral-caudal extent of the CP. The workflow was also applied to select cortico-striatal connections in two different mouse models of disconnection syndromes to demonstrate its utility for characterizing circuitry-specific connectopathies. Together, our results provide the structural basis for studying the functional diversity of the dorsal striatum and disruptions of cortico-basal ganglia networks across a broad range of disorders.
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http://dx.doi.org/10.1038/nn.4332DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5564682PMC
August 2016

High-resolution characterization of a PACAP-EGFP transgenic mouse model for mapping PACAP-expressing neurons.

J Comp Neurol 2016 12 3;524(18):3827-3848. Epub 2016 Jun 3.

Department of Psychiatry, University of California, Los Angeles, USA 90095.

Pituitary adenylate cyclase-activating polypeptide (PACAP, gene name Adcyap1) regulates a wide variety of neurological and physiological functions, including metabolism and cognition, and plays roles in of multiple forms of stress. Because of its preferential expression in nerve fibers, it has often been difficult to trace and identify the endogenous sources of the peptide in specific populations of neurons. Here, we introduce a transgenic mouse line that harbors in its genome a bacterial artificial chromosome containing an enhanced green fluorescent protein (EGFP) expression cassette inserted upstream of the PACAP ATG translation initiation codon. Analysis of expression in brain sections of these mice using a GFP antibody reveals EGFP expression in distinct neuronal perikarya and dendritic arbors in several major brain regions previously reported to express PACAP from using a variety of approaches, including radioimmunoassay, in situ hybridization, and immunohistochemistry with and without colchicine. EGFP expression in neuronal perikarya was modulated in a manner similar to PACAP gene expression in motor neurons after peripheral axotomy in the ipsilateral facial motor nucleus in the brainstem, providing an example in which the transgene undergoes proper regulation in vivo. These mice and the high-resolution map obtained are expected to be useful in understanding the anatomical patterns of PACAP expression and its plasticity in the mouse. J. Comp. Neurol. 524:3827-3848, 2016. © 2016 Wiley Periodicals, Inc.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5063673PMC
http://dx.doi.org/10.1002/cne.24035DOI Listing
December 2016

[Root shape changes of impacted upper central incisor before and after orthodontic traction].

Shanghai Kou Qiang Yi Xue 2016 Feb;25(1):72-6

Research Institute of Pediatric Dentistry, Tongji University. Shanghai 200032, China.

Purpose: Changes of root shape of impacted upper central incisor before and after orthodontic traction were observed with dental cone-beam CT(CBCT), the timing for traction of impacted upper central incisor was investigated.

Methods: Ten impacted maxillary central incisors were diagnosed via panoramic radiograph. CBCT images were taken preoperatively for accurate localization. Following combined treatment of dental surgery and orthodontic traction, ten impacted maxillary central incisors were guided out and aligned well. Final treatment results and the root development status were evaluated via CBCT.

Results: Ten impacted maxillary central incisors were tracted to normal position. CBCT images before and after treatment showed that the root of impacted incisors with completed root apex had no change in shape, while the root of impacted incisors with uncompleted root apex developed continually with obviously improved shape and length.

Conclusions: Optimistic results can be achieved if the traction of impacted upper central incisor is carried out before root development completed.
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February 2016

BAMS2 workspace: a comprehensive and versatile neuroinformatic platform for collating and processing neuroanatomical connections.

J Comp Neurol 2014 Oct 12;522(14):3160-76. Epub 2014 Apr 12.

Department of Biological Sciences, University of Southern California, Los Angeles, California, 90089.

We describe a novel neuroinformatic platform, the BAMS2 Workspace (http://brancusi1.usc.edu), designed for storing and processing information on gray matter region axonal connections. This de novo constructed module allows registered users to collate their data directly by using a simple and versatile visual interface. It also allows construction and analysis of sets of connections associated with gray matter region nomenclatures from any designated species. The Workspace includes a set of tools allowing the display of data in matrix and networks formats and the uploading of processed information in visual, PDF, CSV, and Excel formats. Finally, the Workspace can be accessed anonymously by third-party systems to create individualized connectivity networks. All features of the BAMS2 Workspace are described in detail and are demonstrated with connectivity reports collated in BAMS and associated with the rat sensory-motor cortex, medial frontal cortex, and amygdalar regions.
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http://dx.doi.org/10.1002/cne.23592DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4107155PMC
October 2014

Neural networks of the mouse neocortex.

Cell 2014 Feb;156(5):1096-111

Institute for Neuroimaging and Informatics, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA 90032, USA; Department of Neurology, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA 90032, USA. Electronic address:

Numerous studies have examined the neuronal inputs and outputs of many areas within the mammalian cerebral cortex, but how these areas are organized into neural networks that communicate across the entire cortex is unclear. Over 600 labeled neuronal pathways acquired from tracer injections placed across the entire mouse neocortex enabled us to generate a cortical connectivity atlas. A total of 240 intracortical connections were manually reconstructed within a common neuroanatomic framework, forming a cortico-cortical connectivity map that facilitates comparison of connections from different cortical targets. Connectivity matrices were generated to provide an overview of all intracortical connections and subnetwork clusterings. The connectivity matrices and cortical map revealed that the entire cortex is organized into four somatic sensorimotor, two medial, and two lateral subnetworks that display unique topologies and can interact through select cortical areas. Together, these data provide a resource that can be used to further investigate cortical networks and their corresponding functions.
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http://dx.doi.org/10.1016/j.cell.2014.02.023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4169118PMC
February 2014

High-throughput extraction of β-carotene from Blakeslea trispora based on a newly developed setup.

Biotechnol Appl Biochem 2014 Jul-Aug;61(4):446-52. Epub 2014 Apr 21.

State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.

Rapid and efficient extraction of bioactive compounds from biomass for sample analysis presents one of the major challenges in high-productive strain screening and bioprocess development. In this work, a high-throughput method based on a new setup was developed for the extraction of β-carotene from Blakeslea trispora. After the cell was completely disrupted by high-throughput machinery grinding, β-carotene was completely extracted by chloroform and dimethylsulfoxide (1:1, v/v). According to the experimental results, the newly developed high-throughput extraction (HTPE) method could simultaneously process 96 samples within 30 Min, and only 5-mL solvent was used for each sample. The sufficient extraction of β-carotene by the HTPE method, which was confirmed by the conventional reference extraction method, further demonstrated that the newly developed HTPE method was more efficient and economical than the methods developed previously for the extraction of β-carotene.
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http://dx.doi.org/10.1002/bab.1178DOI Listing
April 2017

Activation of group I metabotropic glutamate receptors enhances persistent sodium current and rhythmic bursting in main olfactory bulb external tufted cells.

J Neurophysiol 2014 Feb 13;111(3):641-7. Epub 2013 Nov 13.

Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, Tennessee.

Rhythmically bursting olfactory bulb external tufted (ET) cells are thought to play a key role in synchronizing glomerular network activity to respiratory-driven sensory input. Whereas spontaneous bursting in these cells is intrinsically generated by interplay of several voltage-dependent currents, bursting strength and frequency can be modified by local intrinsic and centrifugal synaptic input. Activation of metabotropic glutamate receptors (mGluRs) engages a calcium-dependent cation current (I(CAN)) that increases rhythmic bursting, but mGluRs may also modulate intrinsic mechanisms involved in bursting. Here, we used patch-clamp electrophysiology in rat olfactory bulb slices to investigate whether mGluRs modulate two key intrinsic currents involved in ET cell burst initiation: persistent sodium (I(NaP)) and hyperpolarization-activated cation (Ih) currents. Using a BAPTA-based internal solution to block I(CAN), we found that the mGluR1/5 agonist DHPG enhanced I(NaP) but did not alter Ih. I(NaP) enhancement consisted of increased current at membrane potentials between -60 and -50 mV and a hyperpolarizing shift in activation threshold. Both effects would be predicted to shorten the interburst interval. In agreement, DHPG modestly depolarized (∼3.5 mV) ET cells and increased burst frequency without effect on other major burst parameters. This increase was inversely proportional to the basal burst rate such that slower ET cells exhibited the largest increases. This may enable ET cells with slow intrinsic burst rates to pace with faster sniff rates. Taken with other findings, these results indicate that multiple neurotransmitter mechanisms are engaged to fine-tune rhythmic ET cell bursting to context- and state-dependent changes in sniffing frequency.
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http://dx.doi.org/10.1152/jn.00696.2013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3921410PMC
February 2014
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