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Fetal Head Compression: Its Possible Role in Neurologic Inj.ry

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Open j.urnal of Obstetrics and Gynecology 2024年第1期14卷 124-143页

作者： barry S. Schifrin Brian j. Koos Wayne R. Cohen Department of Obstetrics and Gynecology The Western University of Health Sciences Pomona USA The David Geffen School of Medicine at UCLA Los Angeles USA The University of Arizona College of Medicine Tucson USA

It is widely assumed that fetal ischemic brain inj.ry during labor derives almost exclusively from severe, systemic hypoxemia with marked neonatal depression and acidemia. Severe asphyxia, however, is one of several causes of perinatal neurological inj.ry and may not be the most common;most neonates diagnosed with hypoxic-ischemic encephalopathy do not have evidence of severe asphyxia. Sepsis, direct brain trauma, and drug or toxin exposure account for some cases, while mechanical forces of labor and delivery that increase fetal intracranial pressure sufficiently to impair brain perfusion may also contribute. Because of bony compliance and mobile suture lines, the fetal skull changes shape and redistributes cerebrospinal fluid during labor according to constraints imposed by contractions, and bony and soft tissue elements of the birth canal as the head descends. These accommodations, including the increase in intracranial pressure, are adaptive and necessary for efficient descent of the head while safeguarding cerebral blood flow. Autonomic reflexes mediated through central receptors normally provide ample protection of the brain from the considerable pressure exerted on the skull. On occasion, those forces, which are transmitted intracranially, may overcome the various adaptive anatomical, cardiovascular, metabolic, and neurological mechanisms that maintain cerebral perfusion and oxygen availability, resulting in ischemic brain inj.ry. Accepting the notion of a potentially adverse impact of fetal head compression suggests that avoidance of excessive uterine activity and of relentless pushing without steady progress in descent may offer protection for the fetal brain during parturition. Excessive head compression should be considered in the differential diagnosis of ischemic encephalopathy.

关键词： Fetal Brain Inj.ry Fetal Head Compression Ischemic Encephalopathy Neonatal Encephalopathy

Investigation of HCAR2 antagonists as a potential strategy to modulate bovine leukocytes

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j.urnal of Animal Science and Biotechnology 2024年第4期15卷 1567-1577页

作者： Laman K.Mamedova Kirby C.Krogstad Paiton O.McDonald Laxman Pokhrel Duy H.Hua Evan C.Titgemeyer barry j.Bradford Department of Animal Science Michigan State UniversityEast LansingMichigan 48824USA Department of Animal Sciences and Industry Kansas State UniversityManhattanKS 66506USA Comparative Medicine and Integrative Biology East LansingMI 48824USA Department of Chemistry Kansas State UniversityManhattanKS 66506USA

Background Dairy cows experiencing ketosis after calving suffer greater disease incidence and are at greater risk of leaving the herd. In vitro administration of beta-hydroxybutyric acid(BHBA;the primary blood ketone) has inhibitory effects on the function of bovine leukocytes. BHBA is a ligand of HCAR2 and the activation of these receptors promotes an anti-inflammatory response which may be related with immunosuppression observed in transition dairy cattle. The obj.ctive of this study was to identify and test antagonists for HCAR2 in bovine immune cells cultured with *** We observed expression of HCAR2 at the protein level within lymphocytes, monocytes, and granulocytes. The proportion of cells expressing HCAR2 tended to be greater in mid-lactation compared to early lactation cows;the increase was a result of increased proportion of T and B cells expressing HCAR2. Stimulation of HCAR2 with niacin or BHBA promoted Ca^(2+) mobilization in neutrophils and mononuclear cells. Mononuclear cells treated with BHBA had diminished intracellular Ca^(2+) responses when HCAR2 was knocked down by si RNA silencing, indicating Ca^(2+) mobilization was mediated by HCAR2 signaling. Two candidate antagonists for HCAR2, synthesized from niacin(NA-1 and NA-5), were tested;monocytes and neutrophils pre-treated with NA-1 and NA-5 had reduced Ca^(2+) mobilization after incubation with BHBA. Furthermore, NA-5 but not NA-1 prevented BHBA-associated reductions in cyclic *** We demonstrated that HCAR2 is present on bovine leukocytes and has greater expression later in lactation. We confirmed that BHBA and niacin derived HCAR2 antagonists alter bovine leukocyte activity. Our results demonstrate that both BHBA and niacin affect bovine leukocyte Ca^(2+) mobilization in a HCAR2-dependent manner.

关键词： Flow cytometry GPR109A HM74A Ketosis

Cell-cell interactions and communication dynamics in lung fibrosis

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Chinese Medical j.urnal Pulmonary and Critical Care Medicine 2024年第2期2卷 63-71页

作者： Ting Xie j.urong Liang barry Stripp Paul W.Noble Division of Pulmonary and Critical Care Medicine Department of MedicineWomen’s Guild Lung InstituteCedars-Sinai Medical CenterLos AngelesCA 90048USA

Cell-cell interactions are essential components of coordinated cell function in lung *** diseases involve altered cell-cell interactions and communication between different cell types,as well as between subsets of cells of the same *** identification and understanding of intercellular signaling in lung fibrosis offer insights into the molecular mechanisms underlying these interactions and their implications in the development and progression of lung fibrosis.A comprehensive cell atlas of the human lung,established with the facilita-tion of single-cell RNA transcriptomic analysis,has enabled the inference of intercellular communications using ligand-receptor *** this review,we provide a comprehensive overview of the modified cell-cell commu-nications in lung *** highlight the intricate interactions among the maj.r cell types within the lung and their contributions to *** insights presented in this review will contribute to a better understand-ing of the molecular mechanisms underlying lung fibrosis and may guide future research efforts in developing targeted therapies for this debilitating disease.

关键词： Cell–cell interaction Lung fibrosis Lung homeostasis Targeted therapies

THIGEMINAL MECHANISMS OF OROFACIAL PAIN

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神经解剖学杂志 2001年第B7期17卷 35-36页

作者： barry j. SESSLE Department of Physiology Faculty of Dentistry University of Toronto Canada BDS BSc MDS PhD FRSC

Difficulties with the diagnosis and management of acute and chronic pain conditions stem largely from uncertainties of the aetiology or pathogenesis of the conditions. Recent studies have provided some important new insights into the peripheral and central processes underlying pain, and this presentation will review some of the recent advances in our knowledge of the neural processes involved in pain of the orofacial region.

关键词：口面部疼痛机制三叉神经中枢损伤感受器

A History of Fischer-Tropsch Wax Upgrading at BP-from Catalyst Screening Studies to Full Scale Demonstration in Alaska

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j.urnal of Natural Gas Chemistry 2006年第1期15卷 1-10页

作者： j.hn P. Collins j.ep j. H. M. Font Freide barry Nay BP Exploration America Inc. BP Exploration Operating Company

Conversion of Fischer-Tropsch wax into high quality synthetic crude or finished transportation fuels such as premium diesel has been studied over the past 15 years within BP. Catalyst screening and selection was carried out in dedicated micro-reactors and pilot plants, whose designs are critical to the performance selection. Variation in catalyst composition and defining the gas to oil feed ratios with the operating temperature are a few of the parameters studied. Product selection and maximizing diesel yield combined with stability （catalyst life） were the ultimate drivers. The selected catalyst was then tested under commercial conditions in a dedicated 300 barrel per day demonstration plant. The products were also tested in engines to assess their combustion characteristics.

关键词： Fischer-Tropsch wax upgrading hydrocracking synthetic crude diesel naphtha engine emission

Unifying the Software Process Spectrum

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软件学报 2006年第4期17卷 649-657页

作者： Mingshu Li barry W. Boehm Leon j. Osterweil State Key Lab of Computer Science and Lab. for Internet Software Technologies Institute of Software at Chinese Academy of Sciences Beijing 100080 China University of Southern California CA 90089-0781 USA University of Massachusetts Amherst Amherst MA 01003 USA

Software Process Workshop (SPW 2005) was held in Beij.ng on May 25-27, 2005. This paper introduces the motivation of organizing such a workshop, as well as its theme and paper gathering and review; and summarizes the main content and insights of 11 keynote speeches, 30 regular papers in five sessions of “Process Content”, “Process Tools and Metrics”, “Process Management”, “Process Representation and Analysis”, and “Experience Reports”, 8 software development support tools demonstration, and the ending panel “Where Are We Now? Where Should We Go Next?”.

关键词：软件处理微处理宏处理过程表征

Histone Acetylation, VERNALIZATION INSENSITIVE 3, FLOWERING LOCUS C, and the Vernalization Response

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Molecular Plant 2009年第4期2卷 724-737页

作者： Donna M. Bond Elizabeth S. Dennis barry j. Pogson E. j.an Finnegan CSIRO Plant Industry Canberra Australia ARC Centre of Excellence in Plant Energy Biology School of Biochemistry and Molecular Biology Australian National University Canberra Australia

The quantitative induction of VIN3 by low temperatures is required for PRC2 repression of FLC and promotion of flowering （vernalization） in Arabidopsis. Histone acetylation, a chromatin modification commonly associated with gene transcription, increased on VIN3 chromatin in two spatially and temporally distinct phases in response to low temperatures. During short-term cold exposure, histone H3 acetylation at the transcription start site rapidly increased, implying that it is required for VlN3 induction. Subsequent changes in histone H3 and H4 acetylation occurred following continued VIN3 transcription during prolonged cold exposure. Members of the SAGA-like transcriptional adaptor complex, including the histone acetyltransferase GCNS, which induces expression of the cold acclimation pathway genes, do not regulate VlN3 induction during cold exposure, indicating that the cold acclimation pathway and the cold-induction of VlN3 are regulated by different transcriptional mechanisms. Mutations in the other 11 histone acetyltransferase genes did not affect VlN3 induction. However, nicotinamide, a histone deacetyiase inhibitor, induced VIN3 and altered histone acetylation at the VIN3 locus. VIN3 induction was proportional to the length of nicotinamide treatment, which was associated with an early-flowering phenotype and repression of FLC. However, unlike vernalization, the repression of FLC was independent of VIN3 activity. Nicotinamide treatment did not cause a change in the expression of any genes in the autonomous pathway or members of the PRC2 complex, the well characterized repressors of FLC. Our data suggest that FLC is repressed via a novel pathway involving the SIR2 class of histone deacetylases.

关键词： Cold acclimation histone acetyltransferase histone deacetylase SIR2 nicotinamide.

Transcriptional Control of SET DOMAIN GROUP 8 and CAROTENOID ISOMERASE during Arabidopsis Development

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Molecular Plant 2010年第1期3卷 174-191页

作者： Christopher I. Cazzonelli Andrea C. Roberts Melanie E. Carmody barry j. Pogson Australian Research Council Centre of Excellence in Plant Energy Biology Research School of Biology The Australian National University Canberra ACT0200 Australia

Carotenoids are pigments required for photosynthesis, photoprotection and the production of carotenoid- derived hormones such as ABA and strigolactones. The carotenoid biosynthetic pathway bifurcates after lycopene to produce epsilon- and beta-carotenoids and this branch is critical for determining carotenoid composition. Here, we show how the branch point can be regulated by the chromatin-modifying histone methyltransferase, Set Domain Group 8 （SDG8） targeting the carotenoid isomerase （CRTISO）. SDG8 is required to maintain permissive expression of CRTISO during seedling development, in leaves, shoot apex, and some floral organs. The CRTISO and SDG8 promoters show overlapping tissue-specific patterns of reporter gene activity. Interestingly, CRTISO showed atypical reporter gene expression in terms of greater variability between different lines compared to the Cauliflower Mosaic Virus 35S promoter （CaMV35s） and ~LCY promoters, potentially due to chromosomal position effects. Regulation of the CRTISO promoter was dependent in part upon the presence or absence of SDG8. Knockouts of SDG8 （carotenoid and chloroplast regulation （ccrl）） and CRTISO （ccr2） result in altered carotenoid composition and this could be restored in ccr2 using the CaMV35s or CRTISO promoters. In contrast, varying degrees of GUS expression and carotenoid complementation by CRTISO overexpression using CaMV35S or CRTISO promoters in the ccrl background demonstrated that both the CRTISO promoter and open reading frame are necessary for SDG8-mediated expression of CRTISO.

关键词： Photosynthesis secondary metabolism--terpenoids, isoprenoids, and carotenoids chloroplast biology epigenetics gene expression gene regulation.

Robustness Assessment and Adaptive FDI for Car Engine

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International j.urnal of Automation and computing 2008年第2期5卷 109-118页

作者： Mahavir Singh Sangha j.barry Gomm Control Systems Research Group School of EngineeringLiverpool John Moores University

A new on-line fault detection and isolation （FDI） scheme proposed for engines using an adaptive neural network classifier is evaluated for a wide range of operational modes to check the robustness of the scheme in this paper. The neural classifier is adaptive to cope with the significant parameter uncertainty, disturbances, and environment changes. The developed scheme is capable of diagnosing faults in on-line mode and the FDI for the closed-loop system with can be directly implemented in an on-board crankshaft speed feedback is investigated by diagnosis system （hardware）. The robustness of testing it for a wide range of operational modes including robustness against fixed and sinusoidal throttle angle inputs, change in load, change in an engine parameter, and all these changes occurring at the same time. The evaluations are performed using a mean value engine model （MVEM）, which is a widely used benchmark model for engine control system and FDI system design. The simulation results confirm the robustness of the proposed method for various uncertainties and disturbances.

关键词： On-board fault diagnosis automotive engines adaptive neural networks (ANNs) fault classification robustness assessment