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1.
Diabet Med ; 37(8): 1357-1366, 2020 08.
Article in English | MEDLINE | ID: mdl-31808578

ABSTRACT

AIMS: To assess fidelity of the Healthier You: NHS Diabetes Prevention Programme (NHS-DPP), a behavioural intervention for people in England at high risk of developing type 2 diabetes, to the specified programme features. METHODS: Document analysis of the NHS-DPP programme specification, including National Institute for Health and Care Excellence (NICE) PH38 diabetes prevention guidance. This was compared with the intervention design (framework response documents and programme manuals) from all four independent providers delivering the NHS-DPP. Documents were coded using the Template for Intervention Description and Replication framework (describing service parameters) and the Behaviour Change Technique Taxonomy v1. RESULTS: Providers demonstrated good fidelity to service parameters of the NHS-DPP. The NHS-DPP specification indicated 19 unique behaviour change techniques. Framework responses for the four providers contained between 24 and 32 distinct behaviour change techniques, and programme manuals contained between 23 and 45 distinct behaviour change techniques, indicating variation in behaviour change content between providers' intervention documents. Thus, each provider planned to deliver 74% of the unique behaviour change techniques specified, and a large amount of behaviour change content not mandated. CONCLUSIONS: There is good fidelity to the specified service parameters of the NHS-DPP; however, the four providers planned to deliver approximately three-quarters of behaviour change techniques specified by the NHS-DPP. Given that behaviour change techniques are the 'active ingredients' of interventions, and some of these techniques in the programme manuals may be missed in practice, this highlights possible limitations with fidelity to the NHS-DPP programme specification at the intervention design stage.


Subject(s)
Diabetes Mellitus, Type 2/prevention & control , Program Evaluation , Psychosocial Intervention/standards , Behavior Therapy/standards , England , Humans , State Medicine , United Kingdom
2.
Br J Sports Med ; 51(1): 12-19, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27697939

ABSTRACT

OBJECTIVE: To assess the relationships between golf and health. DESIGN: Scoping review. DATA SOURCES: Published and unpublished reports of any age or language, identified by searching electronic databases, platforms, reference lists, websites and from consulting experts. REVIEW METHODS: A 3-step search strategy identified relevant published primary and secondary studies as well as grey literature. Identified studies were screened for final inclusion. Data were extracted using a standardised tool, to form (1) a descriptive analysis and (2) a thematic summary. RESULTS AND DISCUSSION: 4944 records were identified with an initial search. 301 studies met criteria for the scoping review. Golf can provide moderate intensity physical activity and is associated with physical health benefits that include improved cardiovascular, respiratory and metabolic profiles, and improved wellness. There is limited evidence related to golf and mental health. The incidence of golfing injury is moderate, with back injuries the most frequent. Accidental head injuries are rare, but can have serious consequences. CONCLUSIONS: Practitioners and policymakers can be encouraged to support more people to play golf, due to associated improved physical health and mental well-being, and a potential contribution to increased life expectancy. Injuries and illnesses associated with golf have been identified, and risk reduction strategies are warranted. Further research priorities include systematic reviews to further explore the cause and effect nature of the relationships described. Research characterising golf's contribution to muscular strengthening, balance and falls prevention as well as further assessing the associations and effects between golf and mental health are also indicated.


Subject(s)
Golf/physiology , Health Status , Back Injuries/epidemiology , Craniocerebral Trauma/epidemiology , Exercise , Golf/injuries , Humans , Mental Health
3.
Eur Radiol ; 26(10): 3752-9, 2016 Oct.
Article in English | MEDLINE | ID: mdl-26792428

ABSTRACT

OBJECTIVES: This work evaluates rapid magnetic resonance projection hydrography (PH) based amniotic fluid volume (AFV) estimates against established routine ultrasound single deepest vertical pocket (SDVP) and amniotic fluid index (AFI) measurements, in utero at 28-32 weeks gestation. Manual multi-section planimetry (MSP) based measurement of AFV is used as a proxy reference standard. METHODS: Thirty-five women with a healthy singleton pregnancy (20-41 years) attending routine antenatal ultrasound were recruited. SDVP and AFI were measured using ultrasound, with same day MRI assessing AFV with PH and MSP. The relationships between the respective techniques were assessed using linear regression analysis and Bland-Altman method comparison statistics. RESULTS: When comparing estimated AFV, a highly significant relationship was observed between PH and the reference standard MSP (R(2) = 0.802, p < 0.001). For the US measurements, SDVP measurement related most closely to amniotic fluid volume, (R(2) = 0.470, p < 0.001), with AFI demonstrating a weaker relationship (R(2) = 0.208, p = 0.007). CONCLUSION: This study shows that rapid MRI based PH measurement is a better predictor of AFV, relating more closely to our proxy standard than established US techniques. Although larger validation studies across a range of gestational ages are required this approach could form part of MR fetal assessment, particularly where poly- or oligohydramnios is suspected. KEY POINTS: • MR projection hydrography can be used to estimate amniotic fluid volume. • MR projection hydrography relies on the T2w signal from amniotic fluid. • Amniotic fluid volume (AFV) is more accurately assessed than with ultrasound.


Subject(s)
Amniotic Fluid/diagnostic imaging , Magnetic Resonance Imaging/methods , Prenatal Diagnosis/methods , Adult , Female , Gestational Age , Humans , Observer Variation , Pregnancy , Ultrasonography, Prenatal , Young Adult
4.
Br J Sports Med ; 50(11): 647-50, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27130924

ABSTRACT

INTRODUCTION: Golf is a sport played in 206 countries worldwide by over 50 million people. It is possible that participation in golf, which is a form of physical activity, may be associated with effects on longevity, the cardiovascular, metabolic and musculoskeletal systems, as well as on mental health and well-being. We outline our scoping review protocol to examine the relationships and effects of golf on physical and mental health. METHODS AND ANALYSIS: Best practice methodological frameworks suggested by Arksey and O'Malley, Levac et al and the Joanna Briggs Institute will serve as our guide, providing clarity and rigour. A scoping review provides a framework to (1) map the key concepts and evidence, (2) summarise and disseminate existing research findings to practitioners and policymakers and (3) identify gaps in the existing research. A three-step search strategy will identify reviews as well as original research, published and grey literature. An initial search will identify suitable search terms, followed by a search using keyword and index terms. Two reviewers will independently screen identified studies for final inclusion. DISSEMINATION: We will map key concepts and evidence, and disseminate existing research findings to practitioners and policymakers through peer-reviewed and non-peer reviewed publications, conferences and in-person communications. We will identify priorities for further study. This method may prove useful to examine the relationships and effects of other sports on health.


Subject(s)
Golf/psychology , Mental Health , Research Design , Databases, Factual , Humans
5.
Br J Sports Med ; 52(6): 413-414, 2018 Mar.
Article in English | MEDLINE | ID: mdl-27660371
6.
Br J Sports Med ; 51(1): 20-21, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27697934
7.
Clin Radiol ; 66(11): 1049-54, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21763645

ABSTRACT

AIM: To document the timing of the appearance of the radiological features of fracture healing in a group of infants in which the date of injury was known and to assess the degree of interobserver agreement. MATERIALS AND METHODS: Three paediatric radiologists independently assessed 161 images of 37 long bone fractures in 31 patients aged 0-44 months. The following features were assessed: soft-tissue swelling, subperiosteal new bone formation (SPNBF), definition of fracture line, presence or absence of callus, whether callus was well or ill defined, and the presence of endosteal callus. RESULTS: Agreement between observers was only moderate for all discriminators except SPNBF. SPNBF was invariably seen after 11 days but was uncommon before this time even in the very young. In one case SPNBF was seen at 4 days. CONCLUSION: With the exception of SPNBF, the criteria relied on to date fractures are either not reproducible or are poor discriminators of fracture age.


Subject(s)
Femoral Fractures/diagnostic imaging , Fracture Healing , Humeral Fractures/diagnostic imaging , Radius Fractures/diagnostic imaging , Tibial Fractures/diagnostic imaging , Ulna Fractures/diagnostic imaging , Child, Preschool , Female , Femoral Fractures/physiopathology , Humans , Humeral Fractures/physiopathology , Infant , Infant, Newborn , Male , Observer Variation , Radiography , Radius Fractures/physiopathology , Retrospective Studies , Tibial Fractures/physiopathology , Time Factors , Ulna Fractures/physiopathology
9.
Reprod Toxicol ; 93: 199-210, 2020 04.
Article in English | MEDLINE | ID: mdl-32126282

ABSTRACT

The framework for developmental toxicity testing has remained largely unchanged for over 50 years and although it remains invaluable in assessing potential risks in pregnancy, knowledge gaps exist, and some outcomes do not necessarily correlate with clinical experience. Advances in omics, in silico approaches and alternative assays are providing opportunities to enhance our understanding of embryo-fetal development and the prediction of potential risks associated with the use of medicines in pregnancy. A workshop organised by the Medicines and Healthcare products Regulatory Agency (MHRA), "Predicting the Safety of Medicines in Pregnancy - a New Era?", was attended by delegates representing regulatory authorities, academia, industry, patients, funding bodies and software developers to consider how to improve the quality of and access to nonclinical developmental toxicity data and how to use this data to better predict the safety of medicines in human pregnancy. The workshop delegates concluded that based on comparative data to date alternative methodologies are currently no more predictive than conventional methods and not qualified for use in regulatory submissions. To advance the development and qualification of alternative methodologies, there is a requirement for better coordinated multidisciplinary cross-sector interactions coupled with data sharing. Furthermore, a better understanding of human developmental biology and the incorporation of this knowledge into the development of alternative methodologies is essential to enhance the prediction of adverse outcomes for human development. The output of the workshop was a series of recommendations aimed at supporting multidisciplinary efforts to develop and validate these alternative methodologies.


Subject(s)
Drug-Related Side Effects and Adverse Reactions , Maternal-Fetal Exchange , Adverse Outcome Pathways , Animal Testing Alternatives , Animals , Drug Evaluation, Preclinical , Drug and Narcotic Control , Female , Humans , Pregnancy , Quantitative Structure-Activity Relationship , Toxicity Tests
10.
J Cell Biol ; 147(3): 645-58, 1999 Nov 01.
Article in English | MEDLINE | ID: mdl-10545507

ABSTRACT

Duchenne muscular dystrophy is a fatal muscle disease that is often associated with cognitive impairment. Accordingly, dystrophin is found at the muscle sarcolemma and at postsynaptic sites in neurons. In muscle, dystrophin forms part of a membrane-spanning complex, the dystrophin-associated protein complex (DPC). Whereas the composition of the DPC in muscle is well documented, the existence of a similar complex in brain remains largely unknown. To determine the composition of DPC-like complexes in brain, we have examined the molecular associations and distribution of the dystrobrevins, a widely expressed family of dystrophin-associated proteins, some of which are components of the muscle DPC. beta-Dystrobrevin is found in neurons and is highly enriched in postsynaptic densities (PSDs). Furthermore, beta-dystrobrevin forms a specific complex with dystrophin and syntrophin. By contrast, alpha-dystrobrevin-1 is found in perivascular astrocytes and Bergmann glia, and is not PSD-enriched. alpha-Dystrobrevin-1 is associated with Dp71, utrophin, and syntrophin. In the brains of mice that lack dystrophin and Dp71, the dystrobrevin-syntrophin complexes are still formed, whereas in dystrophin-deficient muscle, the assembly of the DPC is disrupted. Thus, despite the similarity in primary sequence, alpha- and beta-dystrobrevin are differentially distributed in the brain where they form separate DPC-like complexes.


Subject(s)
Dystrophin-Associated Proteins , Dystrophin/metabolism , Membrane Proteins/metabolism , Neuroglia/metabolism , Neurons/metabolism , Amino Acid Sequence , Animals , Brain/cytology , Brain/metabolism , Cytoskeletal Proteins/metabolism , Dystrophin/analogs & derivatives , Dystrophin/deficiency , Dystrophin/genetics , Gene Deletion , Immune Sera/immunology , Membrane Proteins/deficiency , Membrane Proteins/genetics , Membrane Proteins/immunology , Mice , Mice, Transgenic , Molecular Sequence Data , Muscle Proteins/metabolism , Muscular Dystrophy, Duchenne/metabolism , Nerve Tissue Proteins/metabolism , Neurons/cytology , Protein Binding , Protein Isoforms/deficiency , Protein Isoforms/genetics , Protein Isoforms/immunology , Protein Isoforms/metabolism , Rats , Solubility , Synaptosomes/metabolism , Utrophin
11.
Neuroscience ; 153(4): 1190-201, 2008 Jun 02.
Article in English | MEDLINE | ID: mdl-18455884

ABSTRACT

The mammalian cerebellum is composed of a highly reproducible array of transverse zones, each of which is subdivided into parasagittal stripes. By using a combination of Purkinje cell antigenic markers and afferent tracing, four transverse zones have been identified: the anterior zone (AZ: approximately lobules I-V), the central zone (CZ: approximately lobules VI-VII), the posterior zone (PZ: approximately lobules VIII-dorsal IX) and the nodular zone (NZ: approximately ventral lobule IX+lobule X). Neurofilament-associated antigen (NAA) is an epitope recognized by a monoclonal antibody, which is expressed strongly in association with neurofilaments. During perinatal cerebellar development, anti-NAA immunocytochemistry reveals novel features of cerebellar organization. In particular, the CZ is reproducibly subdivided into anterior and posterior components. Between embryonic day 17 and postnatal day 7 NAA immunoreactivity is expressed selectively by a parallel fiber bundle that is restricted to lobule VII, thereby distinguishing the CZ anterior (lobules VIa, b) from the CZ posterior (lobule VII). The novel restriction boundary at lobule VII/VIII, which is also reflected in the morphology of the external granular layer and aligns with a gap in the developing Purkinje cell layer, precedes the morphological appearance of the posterior superior fissure between lobules VIb and VII. In addition, afferent axons to the CZ terminate in an array of parasagittal stripes that is probably a specific climbing fiber projection. Thus, the transverse zone architecture of the mouse cerebellum is more complex than had previously been appreciated.


Subject(s)
Cerebellum/anatomy & histology , Gene Expression Regulation, Developmental/physiology , Nerve Tissue Proteins/metabolism , Neurofilament Proteins/metabolism , Animals , Animals, Newborn , Body Patterning/physiology , Calbindins , Cerebellum/embryology , Cerebellum/growth & development , Embryo, Mammalian , Epitopes/genetics , Epitopes/metabolism , Eye Proteins/metabolism , Homeodomain Proteins/metabolism , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nerve Tissue Proteins/genetics , Neuropeptides/metabolism , PAX6 Transcription Factor , Paired Box Transcription Factors/metabolism , Purkinje Cells/metabolism , Repressor Proteins/metabolism , S100 Calcium Binding Protein G/metabolism
13.
Neuroscience ; 150(4): 863-79, 2007 Dec 19.
Article in English | MEDLINE | ID: mdl-18031938

ABSTRACT

Subventricular zone (SVZ)-derived adult neurospheres express two ectonucleotidases, nucleoside triphosphate diphosphohydrolase 2 (NTPDase2) and tissue non-specific alkaline phosphatase (TNAP). Agonists of the nucleotide receptors P2Y(1) and P2Y(2) as well as adenosine augment growth factor-mediated progenitor cell proliferation. NTPDase2 converts ATP and UTP to ADP and UDP, respectively, which are all P2Y receptor agonists. TNAP hydrolyzes nucleoside triphosphates and diphosphates and produces the P1 receptor agonist adenosine. In the SVZ, NTPDase2 is specifically expressed by type B cells. In order to further scrutinize the association of key molecules of the purinergic signaling pathway with neurogenic regions, we analyzed the expression of TNAP at the lateral ventricles of the adult and developing mouse brain. In the adult brain, TNAP was expressed by type B, type A and at least subsets of type C cells of the SVZ and throughout the rostral migratory stream. Almost 100% of the proliferating, Ki-67-positive cells of the adult SVZ stained for TNAP, supporting the notion of a ubiquitous association of TNAP with SVZ progenitors. In contrast, NTPDase2-positive progenitors of the dentate gyrus were TNAP-negative. Essentially all cells of the telencephalic vesicle at embryonic day (E) 14 revealed TNAP activity, including doublecortin-positive neuroblasts. During further embryonic development, enhanced TNAP activity became restricted to cells of the ventricular and SVZ. In contrast to TNAP, NTPDase2 was first expressed in the SVZ perinatally, in association with TNAP-positive SVZ border cells. During later development, NTPDase2-positive cells disappeared from the ventricular surface and began to form sheaths around clusters of subventricular doublecortin-positive cells, apparently transforming into type B cells. Our results identify TNAP and NTPDase2 as novel markers for subsets of progenitors in the adult and developing mouse brain. They further support the notion that signaling via extracellular nucleotides and nucleosides contributes to embryonic and adult neurogenesis.


Subject(s)
Adenosine Triphosphatases/metabolism , Cell Differentiation/physiology , Cell Proliferation , Lateral Ventricles/cytology , Nucleoside-Triphosphatase/metabolism , Stem Cells/physiology , Alkaline Phosphatase/metabolism , Animals , Animals, Newborn , Brain/cytology , Brain/embryology , Brain/growth & development , Doublecortin Domain Proteins , Embryo, Mammalian , Excitatory Amino Acid Transporter 1 , Female , Gene Expression Regulation, Developmental , Ki-67 Antigen/metabolism , Lateral Ventricles/embryology , Lateral Ventricles/growth & development , Mice , Microtubule-Associated Proteins/metabolism , Nerve Tissue Proteins/metabolism , Neuropeptides/metabolism , Pregnancy
14.
Technol Cancer Res Treat ; 5(4): 337-41, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16866564

ABSTRACT

As evidenced by the success of PET-CT, there are many benefits from combining imaging modalities into a single scanner. The combination of PET and MR offers potential advantages over PET-CT, including improved soft tissue contrast, access to the multiplicity of contrast mechanisms available to MR, simultaneous imaging and fast MR sequences for motion correction. In addition, PET-MR is more suitable than PET-CT for cancer screening due to the elimination of the radiation dose from CT. A key issue associated with combining PET and MR is the fact that the performance of the photomultiplier tubes (PMTs) used in conventional PET detectors is degraded in the magnetic field required for MR. Two approaches have been adopted to circumvent that issue: retention of conventional, magnetic field-sensitive PMT-based PET detectors by modification of other features of the MR or PET system, or the use of new, magnetic field-insensitive devices in the PET detectors including avalanche photo-diodes (APDs) and silicon photomultipliers (SiPMs). Taking the former approach, we are assembling a modified microPET Focus 120 within a gap in a novel, 1T superconducting magnet. The PMTs are located in a low magnetic field (approximately 30mT) through a combination of magnet design and the use of fiber optic 'bundles'. Two main features of the modified PET system have been tested, namely the effect of using long fiber optic bundles in the PET detector, and the impact of magnetic field upon the performance of the position sensitive PMTs. The design of a modified microPET-MR system for small animal imaging is completed, and assembly and testing is underway.


Subject(s)
Brain/pathology , Magnetic Resonance Imaging/methods , Positron-Emission Tomography/instrumentation , Positron-Emission Tomography/methods , Animals , Electromagnetic Fields , Equipment Design , Image Enhancement , Image Interpretation, Computer-Assisted/methods , Magnetics , Mice , Phantoms, Imaging , Subtraction Technique
15.
Placenta ; 43: 35-40, 2016 07.
Article in English | MEDLINE | ID: mdl-27324097

ABSTRACT

OBJECTIVE: The aim of this work was to evaluate whether the uterine arteries (UtA) could be identified and their flow profiles measured during a fetal MRI examination. A comparison was performed against same day sonographic Doppler assessment. METHODS: 35 normal, healthy, singleton pregnancies at 28-32 weeks gestation underwent routine Doppler examination, followed by MRI examination. The resistivity index (RI) and pulsatility index (PI) of the left and right UtA were measured using phase contrast MRI. Bland Altman statistics were used to compare MRI and ultrasound results. RESULTS: Sixty-nine comparable vessels were analysed. Six vessels were excluded due to artefact or technical error. Bland-Altman analysis demonstrated the ultrasound indices were comparable, although systematically lower than the MRI indices; Right UtA RI bias -0.03 (95% limits of agreement (LOA) -0.27 to +0.20), and left UtA RI bias -0.06 (95% LOA -0.26 to +0.14); Right UtA PI bias -0.06 (95% LOA -0.50 to +0.38), Left UtA PI bias -0.11 (95% LOA -0.54 to +0.32). The inter-rater agreement for the MRI derived PI and RI analysis was good. CONCLUSION: This study demonstrates that in the majority of early third trimester pregnancies, the uterine arteries can be identified, and their flow profiles measured using MRI, and that the derived PI and RI values are comparable with Doppler ultrasound values.


Subject(s)
Magnetic Resonance Imaging , Pregnancy Trimester, Third/physiology , Ultrasonography, Doppler , Uterine Artery/diagnostic imaging , Vascular Resistance/physiology , Female , Humans , Pregnancy , Pulsatile Flow/physiology , Uterine Artery/physiology
16.
J Neurosci ; 21(16): 6195-205, 2001 Aug 15.
Article in English | MEDLINE | ID: mdl-11487642

ABSTRACT

During late gestational and early postnatal development, proliferating cells in the subventricular zones of the lateral ventricles (SVZ) migrate into the gray and white matter of the forebrain and differentiate into astrocytes and oligodendrocytes. Because the cellular composition and structure of the neonatal SVZ is poorly understood, we performed a differential display PCR screen to identify genes preferentially expressed therein. One highly expressed gene encoded aldolase C. We used a specific monoclonal antibody, aldolase C/zebrin II (ALDC/ZII), in combination with markers of glial lineage and proliferation, to characterize the cells that express this gene. In the neonatal SVZ, ALDC/ZII-positive cells, which are generally polygonal and display several processes, have a nonuniform spatial distribution. They do not express vimentin, GFAP, or NG2. A subset of ALDC/ZII-positive cells incorporates bromodeoxyuridine, but progenitors identified by beta-galactosidase expression after infection with recombinant BAG virus do not show ALDC/ZII immunoreactivity. Outside of the SVZ, beta-galactosidase-positive/ALDC/ZII-positive cells have an astrocytic phenotype, suggesting that immunoreactivity was acquired after exit from the SVZ. These studies demonstrate that the neonatal SVZ is composed of different populations of cells that can be characterized by their antigenic phenotype, their proliferative capacity, and their spatial distributions. Nonrandom distributions of different cell types within the SVZ may permit the formation of microenvironments that stimulate the production of cells with specific potentials at appropriate points in development. Analysis of ALDC/ZII expression by astrocyte lineage cells in the neonatal cerebral cortex and white matter may reveal insights into the phenotype and behavior of undifferentiated astrocyte progenitors.


Subject(s)
Astrocytes/metabolism , Fructose-Bisphosphate Aldolase/biosynthesis , Nerve Tissue Proteins/biosynthesis , Prosencephalon/metabolism , Animals , Animals, Newborn , Antibody Specificity , Antigens, Differentiation/biosynthesis , Astrocytes/classification , Astrocytes/cytology , Bromodeoxyuridine/metabolism , Cell Count , Cell Differentiation , Cell Division , Cell Lineage , Cell Movement , Cells, Cultured , Fructose-Bisphosphate Aldolase/genetics , Gene Expression Profiling , Lateral Ventricles/chemistry , Lateral Ventricles/cytology , Lateral Ventricles/metabolism , Nerve Tissue Proteins/genetics , Oligodendroglia/cytology , Oligodendroglia/metabolism , Organ Specificity , Phenotype , Prosencephalon/chemistry , Prosencephalon/cytology , RNA, Messenger/biosynthesis , Rats , Stem Cells/cytology , Stem Cells/metabolism
17.
J Mol Biol ; 175(2): 195-212, 1984 May 15.
Article in English | MEDLINE | ID: mdl-6726809

ABSTRACT

The thermodynamics of melting of bacteriophage T4 lysozyme and four of its mutants have been measured by van't Hoff methods. The effect of pH has been explored and utilized to obtain the dependence of the enthalpy on temperature as suggested by Privalov and co-workers. The enthalpy change is a steep linear function of temperature. delta Cp is large and constant within experimental error. Changes in delta Hu are as large as 30% for a single point mutation. Changes in enthalpy are largely compensated by changes in entropy. Changes in stability, as measured by the free energy of unfolding, are smaller than those of delta H, but are very large in a relative sense, since delta G is very much smaller than delta H. Origins of the destabilization caused by mutations are discussed.


Subject(s)
Muramidase , Mutation , T-Phages/enzymology , Amino Acid Sequence , Circular Dichroism , Hydrogen-Ion Concentration , Muramidase/genetics , Protein Denaturation , T-Phages/genetics , Thermodynamics
18.
J Cereb Blood Flow Metab ; 18(4): 376-85, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9538902

ABSTRACT

Postnatal rats at 7 and 21 days of age were subjected to unilateral hypoxia-ischemia (H/I) by right carotid artery ligation followed by 1.5 to 2 hours of hypoxia (8% oxygen). Brains were frozen at specific intervals of recovery from 0 to 24 hours. Western blots of samples of right and left forebrain were immunodeveloped with a monoclonal antibody specific for ubiquitin, RHUb1. An elevation of ubiquitin conjugate levels in the right compared with the left forebrain of 7-day-old animals was detectable immediately following H/I and increased by close to 60% of control level within 1 hour of recovery. The conjugate immunoreactivity remained at this level for 6 hours but had declined to control levels by 24 hours of recovery. No such increase was observed in response to hypoxia alone. Similar changes were observed in samples from the 21-day-old rat brain. However, the elevation of ubiquitin conjugate levels was of slower onset and persisted longer than observed for the 7-day-old animals. Immunocytochemical studies of brain fixed by immersion in formaldehyde/acetone/methanol showed that ubiquitin-like immunoreactivity was increased in the right, but not left, cerebral cortex and hippocampus of animals subjected to H/I. The data suggest that elevated ubiquitination may represent a neuroprotective response to H/I.


Subject(s)
Brain Ischemia/metabolism , Hypoxia, Brain/metabolism , Prosencephalon/metabolism , Ubiquitins/metabolism , Age Factors , Animals , Animals, Newborn , Animals, Suckling , Antibodies, Monoclonal/immunology , Blotting, Western , Immunoenzyme Techniques , Nerve Tissue Proteins/metabolism , Oxidative Stress , Protein Processing, Post-Translational , Rats , Rats, Wistar , Tissue Fixation , Ubiquitins/immunology
19.
J Comp Neurol ; 256(1): 29-41, 1987 Feb 01.
Article in English | MEDLINE | ID: mdl-3546410

ABSTRACT

Both anatomical and physiological mapping methods have revealed that the mammalian cerebellar cortex consists of a family of parasagittal bands of cells, each band with its own pattern of afferent and efferent axons. Monoclonal antibody mabQ113 recognizes an unknown polypeptide antigen that is confined to a subset of rat cerebellar Purkinje cells. Immunoreactive cells are arranged into parasagittal bands extending throughout the vermis and hemispheres. Expression of the Q113 epitope by individual Purkinje cells may not be all-or-nothing, since the bands tend to be more strongly stained in the vermis than the hemispheres. The band display is symmetrical about the midline and reproducible from individual to individual. Whole-mount immunocytochemistry and serial reconstruction reveal a median band of mabQ113+ Purkinje cells adjacent to the midline (P1+) and six other positive bands disposed symmetrically at either side (P2+ to P7+). Bands are distinct throughout most of the cortex but tend to fuse ventrally and caudally. There are two sources of interindividual differences. Firstly, most animals express supernumerary "satellite" bands in the vermis. Satellite bands are usually only one cell wide, are not bilaterally symmetrical, and differ in position and number from individual to individual. Secondly, the precise position of an individual band can differ, perhaps according to the variable cortical lobulation, for example, the position of P4+ in lobules VIII/IX and P6+ in lobule VII. While a scheme of parasagittal bands is a good description of the vermian organization, the distribution of mabQ113+ and mabQ113- Purkinje cells in the hemispheres may be better described as a checkerboard of antigenic patches.


Subject(s)
Antibodies, Monoclonal , Cerebellar Cortex/immunology , Purkinje Cells/immunology , Animals , Cerebellar Cortex/cytology , Female , Immunoenzyme Techniques , Mice , Mice, Inbred BALB C , Purkinje Cells/cytology , Rats , Rats, Inbred Lew
20.
J Comp Neurol ; 359(2): 197-212, 1995 Aug 21.
Article in English | MEDLINE | ID: mdl-7499524

ABSTRACT

Many mossy fiber afferent projections to the rat cerebellar cortex terminate in parasagittal bands. In particular, the anterior lobe vermis of the cerebellum contains alternating bands of mossy fibers from the spinal cord and external cuneate nuclei. The cerebellar cortical efferents, the Purkinje cells, are also organized in parasagittal bands. These can be revealed by immunochemical staining for the antigen zebrin II, which is selectively expressed by bands of Purkinje cells. In some cases, the boundaries between mossy fiber terminal fields align with identified transitions between zebrin+/- sets of Purkinje cells, whereas others are located within apparently homogeneous Purkinje cell compartments. Two theories can explain the terminal-field topography: In one view, mossy fiber terminals segregate during development, because growth cones from different sources compete for common territory. Alternatively, mossy fiber growth cones directly recognize chemically distinct target territories, and activity-dependent mechanisms play only minor roles. To explore these issues, two sets of experiments were performed. First, the terminal-field map of the neonatal spinocerebellar projection was compared to the Purkinje cell compartmentation as revealed by anticalbindin immunocytochemistry. Second, subsets of spinocerebellar mossy fiber afferents were ablated early in postnatal development, and the consequences for the neighboring cuneocerebellar terminal fields were mapped in the adult with reference to the zebrin II+/- compartments. These experiments revealed no evidence that competitive interactions constrain the mossy fiber terminal-field distribution but, rather, suggest that the organization of the mossy fiber projections follows the compartmentation of the Purkinje cells.


Subject(s)
Brain Mapping , Cell Compartmentation , Cerebellar Cortex/ultrastructure , Nerve Fibers/physiology , Purkinje Cells/ultrastructure , Analysis of Variance , Animals , Animals, Newborn , Calbindins , Cerebellar Cortex/growth & development , Immunohistochemistry , Nerve Tissue Proteins/analysis , Rats , Rats, Sprague-Dawley , S100 Calcium Binding Protein G/analysis
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