In JoVE (1)

Other Publications (33)

Articles by Ke Zou in JoVE

 JoVE Biology

Using Microfluidic Devices to Measure Lifespan and Cellular Phenotypes in Single Budding Yeast Cells

1The State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, School of Physics, Peking University, 2Department of Biochemistry and Biophysics, University of California, San Francisco, 3Peking-Tsinghua Center for Life Sciences at Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University


JoVE 55412

Other articles by Ke Zou on PubMed

[Analysis on the SARS-CoV Genome of PUMC01 Isolate]

Zhongguo Yi Xue Ke Xue Yuan Xue Bao. Acta Academiae Medicinae Sinicae. Oct, 2003  |  Pubmed ID: 14650143

To perform variation and phylogenetics analysis on the SARS-CoV genome sequence (PUMC01) isolated in the Peking Union Medical College Hospital.

[cDNAs Cloning of SARS-CoV PUMC2 Viral Genome]

Zhongguo Yi Xue Ke Xue Yuan Xue Bao. Acta Academiae Medicinae Sinicae. Oct, 2003  |  Pubmed ID: 14650144

To get the cDNA clones which cover the whole genome of SARS-CoV PUMC2 strain.

[Cloning, Expression and Purification of SARS Coronavirus PUMC2 Strain Nucleocapsid Protein]

Zhongguo Yi Xue Ke Xue Yuan Xue Bao. Acta Academiae Medicinae Sinicae. Oct, 2003  |  Pubmed ID: 14650145

To clone, express and purify nucleocapsid protein from SARS coronavirus PUMC2 strain.

The Catalytically Active Domain in the A Subunit of Calcineurin

Biological Chemistry. Oct-Nov, 2003  |  Pubmed ID: 14669985

Calcineurin (CaN) is a heterodimer composed of a catalytic subunit A (CaNA) and a regulatory subunit B (CaNB). We report here an active truncated mutation of the rat CaNAdelta that contains only the catalytic domain (residues 1-347, also known as a/CaNA). The p-nitrophenyl phosphatase activity and protein phosphatase activity of a/CaNA were higher than that of CaNA. Both p-nitrophenyl phosphatase activity and protein phosphatase activity of a/CaNA were unaffected by CaM and the B-subunit; the B-subunit and CaM have relatively little effect on p-nitrophenyl phosphatase activity and a crucial effect on protein phosphatase activity of CaNA. Mn2+ and Ni2+ ions effeciently activated CaNA. The Km of a/CaNA was about 16 mM, and the k(cat) of a/CaNA was 10.03 s(-1) using pNPP as substrate. With RII peptide as a substrate, the Km of a/CaNA was about 21 microM and the k(cat) of a/CaNA was 0.51 s(-1). The optimum reaction temperature was about 45 degrees C, and the optimum reaction pH was about 7.2. Our results indicate that a/CaNA is the catalytic core of CaNA, and CaN and the B-subunit binding domain itself might play roles in the negative regulation of the phosphatase activity of CaN. The results provide the basis for future studies on the catalytic domain of CaN.

Hyaluronan Promotes Tumor Lymphangiogenesis and Intralymphantic Tumor Growth in Xenografts

Acta Biochimica Et Biophysica Sinica. Sep, 2005  |  Pubmed ID: 16143814

Hyaluronan (HA), a high molecular weight glycosaminoglycan in the extracellular matrix, has been implicated in the promotion of malignant phenotypes, including tumor angiogenesis. However, little is known about the effect of HA on tumor-associated lymphangiogenesis. In this study, mouse hepatocellular carcinoma Hca-F cells combined with or without HA were injected subcutaneously into C3H/Hej mice, then angiogenesis and lymphangiogenesis of implanted tumors were examined by immunostaining for platelet-endothelial cell adhesion molecule-1 and lymphatic vascular endothelial hyaluronan receptor-1 respectively. Interestingly, we found HA promotes tumor lymphangiogenesis and the occurrence of intratumoral lymphatic vessels, but has little effect on tumor angiogenesis. Moreover, HA also promotes intralymphatic tumor growth, although it is not sufficient to potentiate lymphatic metastasis. These results suggest that HA, which is elevated in most malignant tumor stroma, may also play a role in tumor progression by promoting lymphangiogenesis.

Downregulation of NFAT5 by RNA Interference Reduces Monoclonal Antibody Productivity of Hybridoma Cells

Cell Research. Mar, 2007  |  Pubmed ID: 17310218

Hybridoma cells display an increase in antibody productivity following exposure to hypertonic conditions. However, the underlying mechanism is not well understood. In the present study, we hypothesize that the nuclear factor of activated T cells 5 (NFAT5)/tonicity enhancer binding protein (TonEBP) functions to increase the antibody productivity of hybridoma cells. NFAT5 is an osmosensitive mammalian transcription factor. However, its ubiquitous expression in various organs that are not bathed in hypertonic milieu suggests that NFAT5 may also regulate cell growth and function under isotonic conditions. In this study, we examined the expression of NFAT5 in hybridoma cells by Western blot analysis, and found that it increased significantly in hypertonic medium. To further define the function of NFAT5 in hybridoma cells, RNA interference technique was used to downregulate the expression of NFAT5 in SGB-8 cells (a hybridoma cell line). In isotonic medium, antibody productivity of hybridoma cells was reduced by downregulation of NFAT5 while cell proliferation was not influenced. The results presented here demonstrate that NFAT5 not only plays an important role in osmotic stress response pathway in hybridoma cells but also is essential for optimal antibody productivity.

Pretreatment with Insulin Enhances Anticancer Functions of 5-fluorouracil in Human Esophageal and Colonic Cancer Cells

Acta Pharmacologica Sinica. May, 2007  |  Pubmed ID: 17439729

To investigate the effects of insulin on enhancing 5-fluorouracil (5-FU) anticancer functions and its mechanisms in the human esophageal cancer cell line (Eca 109) and human colonic cancer cell line (Ls-174-t).

Novel Tumor-associated Antigen of Hepatocellular Carcinoma Defined by Monoclonal Antibody E4-65

Acta Biochimica Et Biophysica Sinica. May, 2007  |  Pubmed ID: 17492133

A monoclonal antibody, E4-65, produced by immunizing mice with SMMC-7721 cells, a human hepatocellular carcinoma (HCC) cell line, was used to identify and characterize an unreported HCC-associated antigen. Indirect immunofluorescence studies showed that E4-65 antibody reacted with five out of eight HCC cell lines, but not with 10 non-HCC tumor cell lines or a normal liver cell line. Using immunohistochemical examination, E4-65 antigen was detected on the cell membranes and in the cytoplasm of human liver tumor tissues, but was not found in most other tumors, or normal adult or fetal tissues, except for a weakly positive reaction in tissues of the digestive system. Western blot analysis showed that E4-65 antibody bound to a 45 kDa protein in the human HCC cell line and tissue lysates. Enzyme treatment and lectin blotting did not detect the carbohydrate chain in E4-65 antigen. This HCC-associated protein represents a potentially useful target for diagnoses and immunotherapy of human HCC.

Identification of FMRP-associated MRNAs Using Yeast Three-hybrid System

American Journal of Medical Genetics. Part B, Neuropsychiatric Genetics : the Official Publication of the International Society of Psychiatric Genetics. Sep, 2008  |  Pubmed ID: 18163424

Fragile X syndrome, one of the most common forms of inherited mental retardation, results from the absence of the fragile X mental retardation protein (FMRP), which is encoded by the fragile X mental retardation gene 1 (FMR1). FMRP is an RNA-binding protein involved in translational regulation of targeted mRNAs. Identification of targeted mRNAs associated with FMRP is important to understand the function of FMRP and the pathogenic basis of the fragile X syndrome. Employing a yeast three-hybrid system and a human fetal hippocampus cDNA library, we identified 22 candidate target mRNAs, and 18 of them were confirmed to be associated with FMRP in vitro by gel retardation. Some of these mRNAs code for structural proteins, enzymes or proteins involved in cellular processes, especially in the development and function of neural system. To further investigate the role of FMRP in regulating targeted gene expression, we analyzed the expression profile of TXNRD1, one of the candidate mRNAs, after knocking down the expression of endogenous FMRP by siRNA. The results showed that endogenous TXNRD1 translation increased along with depletion of FMRP, which suggested FMRP negatively regulates TXNRD1 translation.

Alterations of White Matter Integrity in Adults with Major Depressive Disorder: a Magnetic Resonance Imaging Study

Journal of Psychiatry & Neuroscience : JPN. Nov, 2008  |  Pubmed ID: 18982175

The purpose of our study was to investigate alterations of white matter integrity in adults with major depressive disorder (MDD) using magnetic resonance imaging (MRI).

Magnetization Transfer Imaging Reveals the Brain Deficit in Patients with Treatment-refractory Depression

Journal of Affective Disorders. Oct, 2009  |  Pubmed ID: 19211150

Studies on treatment resistant depression (TRD) using advanced magnetic resonance imaging techniques are very limited.

[A Proton Magnetic Spectroscopy Research on Hippocampus Metabolisms in People with Suicide-attempted Depressions]

Sichuan Da Xue Xue Bao. Yi Xue Ban = Journal of Sichuan University. Medical Science Edition. Jan, 2009  |  Pubmed ID: 19292046

To investigate the metabolic features of hippocampus in people with suicide-attempted depressions.

Depressive Disorders: Focally Altered Cerebral Perfusion Measured with Arterial Spin-labeling MR Imaging

Radiology. May, 2009  |  Pubmed ID: 19401575

To assess focal cerebral perfusion in patients with refractory depressive disorder (RDD), patients with nonrefractory depressive disorder (NDD), and healthy control subjects by using arterial spin-labeling (ASL) magnetic resonance (MR) imaging.

[Brain Evoked Potentials in Patients with Depression or Anxiety]

Sichuan Da Xue Xue Bao. Yi Xue Ban = Journal of Sichuan University. Medical Science Edition. Jul, 2009  |  Pubmed ID: 19764579

To investigate the features and clinical implications of event related potential (ERP) and cognitive-processing in patients with depression, anxiety or both anxiety and depression

[The Mental Health of Children and Adolescents from Earthquake Affected Areas]

Sichuan Da Xue Xue Bao. Yi Xue Ban = Journal of Sichuan University. Medical Science Edition. Jul, 2009  |  Pubmed ID: 19764580

To examine the mental health status of 11-16 years old children exposed to the 5.12 WenChuan earthquake and to help develop post-traumatic psychological interventions.

Changes of Brain Morphometry in First-episode, Drug-naïve, Non-late-life Adult Patients with Major Depression: an Optimized Voxel-based Morphometry Study

Biological Psychiatry. Jan, 2010  |  Pubmed ID: 19897176

Previous structural imaging studies found evidence of brain morphometric changes in major depression (MD) patients, but they rarely excluded compounding effects of some important factors, such as medication and brain degeneration. This study sought to explore the brain morphometric changes of first-episode, drug-naïve, non-late-life adult MD patients with optimized voxel-based morphometry (VBM) method.

Mechanism for Current Saturation and Energy Dissipation in Graphene Transistors

Physical Review Letters. Jun, 2010  |  Pubmed ID: 20867258

From a combination of careful and detailed theoretical and experimental studies, we demonstrate that the Boltzmann theory including all scattering mechanisms gives an excellent account, with no adjustable parameters, of high electric field transport in single as well as double-oxide graphene transistors. We further show unambiguously that scattering from the substrate and superstrate surface optical phonons governs the high-field transport and heat dissipation over a wide range of experimentally relevant parameters. Models that neglect surface optical phonons altogether or treat them in a simple phenomenological manner are inadequate. We outline possible strategies for achieving higher current and complete saturation in graphene devices.

[Randomized Controlled Trial on Comorbid Anxiety and Depression Treated with Electroacupuncture Combined with RTMS]

Zhongguo Zhen Jiu = Chinese Acupuncture & Moxibustion. Apr, 2011  |  Pubmed ID: 21528592

To compare the efficacy differences between integrative therapy of electroacupuncture and repetitive transcranial magnetic stimulation (rTMS) and simple rTMS only in the treatment of comorbid anxiety and depression (CAD).

[Matching Analysis of Event Related Potentials in Patients with Bipolar Disorder]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Jun, 2011  |  Pubmed ID: 21774224

The present paper is to investigate the variation characteristics and clinical application of event related potentials (ERPs) in patients with bipolar disorder. A total of 70 patients with bipolar disorder, with 39 patients in manic phase and 31 patients in depressive phase, and 50 health volunteers were recruited in the case-control study. The ERPs, such as P300, MMN, CNV, P50, were recorded by the Nihon Kohden evoked potential instrument. Compared with the healthy volunteers' latency in the control group, the latency of MMN, CNV, N2, P3a, P3b was longer in the manic phase group; the latency of MMN, CNV, P3a and P3b were longer and the amplitude of CNV was lower in the depressive phase group. The S2/S1 value of P50 obviously increased among the manic phase patients. With manic phase or depression phase of bipolar disorder, the variation characteristics of ERPs were different. The features of ERP reflect the cognitive dysfunction and sensory gating impairment of patient's brain. The results provide neural electrophysiological basis for clinical diagnosis and therapy of bipolar disorder.

Molecular Phenotyping of Aging in Single Yeast Cells Using a Novel Microfluidic Device

Aging Cell. Aug, 2012  |  Pubmed ID: 22498653

Budding yeast has served as an important model organism for aging research, and previous genetic studies have led to the discovery of conserved genes/pathways that regulate lifespan across species. However, the molecular causes of aging and death remain elusive, because it is very difficult to directly observe the cellular and molecular events accompanying aging in single yeast cells by the traditional approach based on micromanipulation. We have developed a microfluidic system to track individual mother cells throughout their lifespan, allowing automated lifespan measurement and direct observation of cell cycle dynamics, cell/organelle morphologies, and various molecular markers. We found that aging of the wild-type cells is characterized by an increased general stress and a progressive lengthening of the cell cycle for the last few cell divisions; these features are much less apparent in the long-lived FOB1 deletion mutant. Following the fate of individual cells revealed that there are different forms of cell death that are characterized by different terminal cell morphologies, and associated with different levels of stress and lifespan. We have identified a molecular marker - the level of the expression of Hsp104, as a good predictor for the lifespan of individual cells. Our approach allows detailed molecular phenotyping of single cells in the process of aging and thus provides new insight into its mechanism.

Natural Killer T-cell Lymphoma Originating from the Orbit

Chinese Medical Journal. May, 2012  |  Pubmed ID: 22800846

Natural killer T-cell lymphoma (NKTL) is a malignant neoplasm which usually involves the nasal cavity or paranasal sinuses, while an orbit origin is extremely rare. Here we report the clinical, radiological and histopathologic features of a patient with NKTL originating from the orbit. We analyzed the clinical and radiologic records in the whole course of the disease. We also reviewed the morphology and immunohistochemistry of the neoplasm biopsy, including the presence of CD56, CD3 and cytotoxic molecules. This case demonstrated that nasal-type NKTL with a poor prognosis can originate from the orbit.

Insect-inspired High-speed Motion Vision System for Robot Control

Biological Cybernetics. Oct, 2012  |  Pubmed ID: 22864467

The mechanism for motion detection in a fly's vision system, known as the Reichardt correlator, suffers from a main shortcoming as a velocity estimator: low accuracy. To enable accurate velocity estimation, responses of the Reichardt correlator to image sequences are analyzed in this paper. An elaborated model with additional preprocessing modules is proposed. The relative error of velocity estimation is significantly reduced by establishing a real-time response-velocity lookup table based on the power spectrum analysis of the input signal. By exploiting the improved velocity estimation accuracy and the simple structure of the Reichardt correlator, a high-speed vision system of 1 kHz is designed and applied for robot yaw-angle control in real-time experiments. The experimental results demonstrate the potential and feasibility of applying insect-inspired motion detection to robot control.

Single Cell Analysis of Yeast Replicative Aging Using a New Generation of Microfluidic Device

PloS One. 2012  |  Pubmed ID: 23144860

A major limitation to yeast aging study has been the inability to track mother cells and observe molecular markers during the aging process. The traditional lifespan assay relies on manual micro-manipulation to remove daughter cells from the mother, which is laborious, time consuming, and does not allow long term tracking with high resolution microscopy. Recently, we have developed a microfluidic system capable of retaining mother cells in the microfluidic chambers while removing daughter cells automatically, making it possible to observe fluorescent reporters in single cells throughout their lifespan. Here we report the development of a new generation of microfluidic device that overcomes several limitations of the previous system, making it easier to fabricate and operate, and allowing functions not possible with the previous design. The basic unit of the device consists of microfluidic channels with pensile columns that can physically trap the mother cells while allowing the removal of daughter cells automatically by the flow of the fresh media. The whole microfluidic device contains multiple independent units operating in parallel, allowing simultaneous analysis of multiple strains. Using this system, we have reproduced the lifespan curves for the known long and short-lived mutants, demonstrating the power of the device for automated lifespan measurement. Following fluorescent reporters in single mother cells throughout their lifespan, we discovered a surprising change of expression of the translation elongation factor TEF2 during aging, suggesting altered translational control in aged mother cells. Utilizing the capability of the new device to trap mother-daughter pairs, we analyzed mother-daughter inheritance and found age dependent asymmetric partitioning of a general stress response reporter between mother and daughter cells.

A Case of Early Onset Parkinson's Disease After Major Stress

Neuropsychiatric Disease and Treatment. 2013  |  Pubmed ID: 23950648

A 38-year-old woman experienced sudden onset of rest tremor in the left forearm 1 week after learning that her deeply loved husband was involved in an affair. The patient was in good health and had no neurological disease or prior trauma. The surface electromyography results were consistent with features of the typical rest tremor, and the increased glucose metabolism in the putamen, seen on positron emission tomography scan, was consistent with the early stages of Parkinson's disease (PD). Furthermore, her trembling symptoms were relieved significantly after antiparkinsonian medications. For this patient, stress played an important role in the development of PD. The mechanism may have been the direct effects of numerous neurotransmitters or dopamine depletion after its massive release during severe stress. This case suggests that severe stress can worsen the neurological symptoms and prompted early onset of PD. It is the first case of PD occurring so early in life after exposure to major stress, and arouses our attention to the effects of stress on the nervous system.

[Study the Effects of Neuroplasticity on Major Depression Disorder in RTMS Combined with Antidepressant Treatments]

Sichuan Da Xue Xue Bao. Yi Xue Ban = Journal of Sichuan University. Medical Science Edition. Jul, 2013  |  Pubmed ID: 24059116

To explore the effects of neuroplasticity on major depression disorder (MDD) with event related potentials (ERPs) of mismatch negativity (MMN) and sensory gating potentials P50 for repetitive transcranial magnetic stimulation (rTMS) combined with antidepressant treatments.

Template-independent, in Situ Grown DNA Nanotail Enabling Label-free Femtomolar Chronocoulometric Detection of Nucleic Acids

Analytical Chemistry. Dec, 2014  |  Pubmed ID: 25369556

A routine electrochemical DNA (E-DNA) sensor requires either an exquisite design of conformation-switchable recognition probe that is critical to facilitate electron transfer at a sensing interface, or a template-dependent DNA amplification, which often involves designing prone-to-false "sticky ends" and labeling redox tags at one end of the signal probes. Here we report an in situ grown DNA nanotail (IGT)-mediated straightforward and template-free signal amplification strategy for highly sensitive and sequence-specific DNA detection. This novel electrochemical IGT (E-IGT) DNA sensor can quantify target nucleic acids in a label-free manner because the electrochemical signals are generated by chronocoulometric interrogation of redox [Ru(NH3)6](3+) that electrostatically and quantitatively binds to the negatively charged phosphate moieties in the electrode surface-attached DNA. By introduction of terminal deoxynucleoside transferase (TdT) to this sensor design, both the sensitivity and selectivity have been significantly enhanced. This DNA sensor achieves an impressive detection limit of 20 fM for a DNA sequence with 22 nucleotides, which is lower than that of an analogous optical DNA sensor by 2 orders of magnitude. More importantly, it exhibits excellent selectivity against even a single-base mismatched sequence. In addition, this novel DNA sensor presents reliable reusability and is capable of measuring target DNA in complex matrixes, such as undiluted human serum, with minimal interference. These advantages make our E-IGT sensor a promising contender in the E-DNA sensor family for medical diagnostics.

[Early Signs of Cognitive Impairment in Patients with Obstructive Sleep Apnea Hypopnea Syndrome: an Event-related Potential Study]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Aug, 2014  |  Pubmed ID: 25464805

This study seeks to explore the early signs of cognitive impairment in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). According to polysomnography, twenty patients diagnosed with OSAHS and twenty normal controls underwent event-related potential (ERP) examination including mismatch negativity (MMN) and P300. Compared with normal controls, OSAHS patients showed significantly prolonged latency of MMN and P300 at Cz. After controlling age and body mass index (BMI), MMN latency positively correlated with apnea hypopnea index (AHI), oxygen reduction index, stage N1 sleep and arousal index, while MMN latency negatively correlated with stage N3 sleep and mean blood oxygen saturation; and P300 latency positively related to AHI and oxygen reduction index; no relationships were found among MMN latency, MMN amplitude, P300 latency and P300 amplitude. These results suggest that the brain function of automatic processing and controlled processing aere impaired in OSAHS patients, and these dysfunction are correlated with nocturnal repeatedly hypoxemia and sleep structure disturbance.

[Early Signs of Cognitive Impairment in Patients with Obstructive Sleep Apnea Hypopnea Syndrome: an Event-related Potential Study]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi = Journal of Biomedical Engineering = Shengwu Yixue Gongchengxue Zazhi. Aug, 2014  |  Pubmed ID: 25508436

This study seeks to explore the early signs of cognitive impairment in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). According to polysomnography, twenty patients diagnosed with OSAHS and twenty normal controls underwent event-related potential (ERP) examination including mismatch negativity (MMN) and P300. Compared with normal controls, OSAHS patients showed significantly prolonged latency of MMN and P300 at Cz. After controlling age and body mass index (BMI), MMN latency positively correlated with apnea hypopnea index (AHI), oxygen reduction index, stage N1 sleep and arousal index, while MMN latency negatively correlated with stage N3 sleep and mean blood oxygen saturation; and P300 latency positively related to AHI and oxygen reduction index; no relationships were found among MMN latency, MMN amplitude, P300 latency and P300 amplitude. These results suggest that the brain function of automatic processing and controlled processing aere impaired in OSAHS patients, and these dysfunction are correlated with nocturnal repeatedly hypoxemia and sleep structure disturbance.

Abnormal Functional Connectivity Density in First-episode, Drug-naive Adult Patients with Major Depressive Disorder

Journal of Affective Disorders. Apr, 2016  |  Pubmed ID: 26826535

Previous studies have found evidence of brain functional connectivity (FC) changes with pre-selected region-of-interest (ROI) method in major depressive disorder (MDD). However, these studies could not completely exclude personal inequality when drawing ROIs manually and did not measure the total number of FC for each voxel. Here, we firstly applied functional connectivity density (FCD) mapping, a voxel-based analysis to locate the hubs with amount changes of FC between 22 first-episode, drug-naive adult MDD patients and 22 healthy control (HC) subjects. Both short-range (local) FCD and long-range (distal) FCD were measured. The relationships of FCD changes with Hamilton Depression Rating Scale (HAMD) scores and illness duration were also explored. Compared with the HC group, MDD patients showed significantly decreased short-range FCD in the left superior temporal gyrus (STG), the right orbital frontal cortex (OFC) and bilateral precuneus, while significantly decreased long-range FCD was found in bilateral middle occipital gyrus (MOG), superior occipital gyrus (SOG) and right calcarine. These results firstly demonstrated both local and distal alterations of connection amount at voxel level, and highlighted that the OFC, the precuneus, the STG and the visual cortex were important brain network hubs for first-episode, drug-naive adult MDD patients. Our findings were complementary for previous structural and functional studies in MDD patients, and provided new evidence of the dysfunction of connection hubs in the pathophysiology of MDD at voxel level.

Causal Connectivity Alterations of Cortical-subcortical Circuit Anchored on Reduced Hemodynamic Response Brain Regions in First-episode Drug-naïve Major Depressive Disorder

Scientific Reports. Feb, 2016  |  Pubmed ID: 26911651

Some efforts were done to investigate the disruption of brain causal connectivity networks involved in major depressive disorder (MDD) using Granger causality (GC) analysis. However, the homogenous hemodynamic response function (HRF) assumption over the brain may disturb the inference of temporal precedence. Here we applied a blind deconvolution approach to examine the altered HRF shape in first-episode, drug-naïve MDD patients. The regions with abnormal HRF shape in patients were chosen as seeds to detect the GC alterations in MDD. The results demonstrated significantly decreased magnitude of spontaneous hemodynamic response of the orbital frontal cortex (OFC) and the caudate nucleus (CAU) in MDD comparing to healthy controls, suggesting MDD patients likely had alterations in neurovascular coupling and cerebrovascular physiology in these two regions. GC mapping showed increased/decreased GC in OFC-/CAU centered networks in MDD. The outgoing GC values from OFC to anterior cingulate cortex and occipital regions were positively correlated with Hamilton Depression Scale (HAMD) scores, while the incoming GC from insula, middle and superior temporal gyrus to CAU were negatively correlated with HAMD scores of MDD. The abnormalities of directional connections in the cortico-subcortico-cerebellar network may lead to unbalanced integrating the emotional-related information for MDD, and further exacerbating depressive symptoms.

A Case of Behavioural Hyperventilation Associated with Severe Central Sleep Apnoea and Follow-up Management

Thorax. Jun, 2016  |  Pubmed ID: 27009945

A Global Characterization of the Translational and Transcriptional Programs Induced by Methionine Restriction Through Ribosome Profiling and RNA-seq

BMC Genomics. Feb, 2017  |  Pubmed ID: 28212626

Among twenty amino acids, methionine has a special role as it is coded by the translation initiation codon and methionyl-tRNAi (Met-tRNAi) is required for the assembly of the translation initiation complex. Thus methionine may play a special role in global gene regulation. Methionine has also been known to play important roles in cell growth, development, cancer, and aging. In this work, we characterize the translational and transcriptional programs induced by methionine restriction (MetR) and investigate the potential mechanisms through which methionine regulates gene expression, using the budding yeast S. cerevisiae as the model organism.

Different Frequency Repetitive Transcranial Magnetic Stimulation (rTMS) for Posttraumatic Stress Disorder (PTSD): A Systematic Review and Meta-analysis

Journal of Psychiatric Research. Feb, 2017  |  Pubmed ID: 28278422

Posttraumatic stress disorder (PTSD) is a psychiatric disorder. Repetitive transcranial magnetic stimulation (rTMS) has been found to be effective for treating PTSD, but whether different frequencies have different effects remains controversial. We conducted this systematic review and meta-analysis to address this question. We searched the literature for studies written in English or Chinese in 9 electronic databases from the databases' inception to August 1, 2016. Additional articles were identified from the reference lists of identified studies and from personal reference collections. Eighteen articles were included, and 11 were suitable for the meta-analysis (Combined sample size was 377 (217 in active rTMS groups, 160 in sham-controlled groups)). Low-frequency (LF) rTMS resulted in a significant reduction in the PTSD total score and the depression score (1. PTSD total score: pooled SMD, 0.92; CI, 0.11-1.72; 2. Depression: pooled SMD, 0.54; CI, 0.08-1.00). High-frequency (HF) rTMS showed the following results: 1. PTSD total score: pooled SMD, 3.24; CI, 2.24-4.25; 2. re-experiencing: pooled SMD, -1.77; CI, -2.49-(-1.04); 3. Avoidance: pooled SMD, -1.57; CI, -2.50-(-0.84); 4. hyperarousal: pooled SMD, -1.32; CI, -2.17-(-0.47); 5. depression: pooled SMD, 1.92; CI, 0.80-3.03; and 6. Anxiety: pooled SMD, 2.67; CI, 1.82-3.52. Therefore, both HF and LF rTMS can alleviate PTSD symptoms. Although the evidence is extremely limited, LF rTMS can reduce overall PTSD and depression symptoms. HF rTMS can improve the main and related symptoms of PTSD. However, additional research is needed to substantiate these findings.

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