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1.
Midwifery ; 63: 33-38, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29777966

ABSTRACT

OBJECTIVE: The current study uses two antipodal social science theories, the rational choice theory and the habitus theory, and applies these to describe how women choose between intraclinical (i.e., hospital-run birth clinics) and extraclinical (i.e., midwife-led birth centres or home births) delivery places. DESIGN, SETTING, PARTICIPANTS, MEASUREMENTS: Data were collected in a cross-sectional questionnaire-based survey among 189 women. A list of 22 determinants, conceptualized to capture the two theoretical concepts, were rated on a 7-point Likert scale with 1 = unimportant to 7 = very important. The analytic method was structural equation modelling. A model was built, in which the rational choice theory and the habitus theory as latent variables predicted the choice of delivery place. FINDINGS: With regards to the choice of delivery place, 89.3% of the women wanted an intraclinical and 10.7% an extraclinical delivery place at the time of their last child's birth. Significant differences between women with a choice of an intraclinical or extraclinical delivery place were found for 14 of the 22 determinants. In the structural equation model, rational choice theory determinants predicted a choice of intraclinical delivery and habitus theory determinants predicted a choice of extraclinical delivery. KEY CONCLUSIONS: The two theories had diametrically opposed effects on the choice of delivery place. Women are more likely to decide on intraclinical delivery when arguments such as high medical standards, positive evaluations, or good advanced information are rated important. In contrast, women are more likely to decide on extraclinical delivery when factors such as family atmosphere during birth, friendliness of health care professionals, or consideration of the woman's interests are deemed important. IMPLICATIONS FOR PRACTICE: A practical implication of our study is that intraclinical deliveries may be promoted by providing comprehensive information, data and facts on various delivery-related issues, while extraclinical deliveries may be fostered by healthcare professionals tailoring personal or social beliefs, attitudes and opinions. Our study advocates that legislation and policy- and decision-makers should support different delivery place options in order to accommodate the choices and preferences of different women. The study demonstrates the usefulness of theory for describing and explaining a complex decision-making process, here the choice of delivery place.


Subject(s)
Choice Behavior , Decision Making , Labor, Obstetric/psychology , Adult , Cross-Sectional Studies , Female , Home Childbirth/psychology , Home Childbirth/statistics & numerical data , Humans , Obstetrics and Gynecology Department, Hospital/statistics & numerical data , Pregnancy , Surveys and Questionnaires
2.
Dalton Trans ; 45(42): 16789-16798, 2016 Oct 25.
Article in English | MEDLINE | ID: mdl-27778000

ABSTRACT

Catalytic hydrodefluorination of perfluoroallylbenzene with Cp2TiH in THF is unselective and yields a variety of previously unknown compounds, predominantly activated in the allylic position. Several different mechanisms have been examined in detail using solvent corrected (THF) DFT(M06-2X) calculations for the archetypal perfluorinated olefin perfluoropropene and perfluoroallylbenzene: (a) single electron transfer, (b) hydrometallation/fluoride elimination, (c) σ-bond metathesis (allylic or vinylic), and (d) nucleophilic vinylic substitution (SNV, w/o Ti-F contacts in the TS). SNV is shown to be a competitive mechanism to hydrometallation and proceeds via ionic species from which F-elimination is facile and unselective leading to low selectivity in polar solvents. Subsequent experiments show that selectivity can be increased in a non-polar solvent.

3.
Chem Asian J ; 11(21): 3062-3071, 2016 Nov 07.
Article in English | MEDLINE | ID: mdl-27529467

ABSTRACT

Several functionalized and non-functionalized perfluoroarenes were catalytically transformed into their para-hydrodefluorinated products by using catalytic amounts of titanocene difluoride and stoichiometric amounts diphenylsilane. Turnover numbers of up to 93 were observed. Solution density functional theory calculations at the M06-2X/TZ(PCM)//M06-2X/TZ(PCM) level of theory provided insight into the mechanism of TiIII -catalyzed aromatic hydrodefluorination. Two different substrate approaches, with a Ti-F interaction (pathway A) and without a Ti-F interaction (pathway B), are possible. Pathway A leads to a σ-bond metathesis transition state, whereas pathway B proceeds by means of a two-step mechanism through a syn-hydrometalation intermediate or through a Meisenheimer intermediate. Both pathways are competitive over a broad range of substrates.

4.
Chemistry ; 22(27): 9305-10, 2016 Jun 27.
Article in English | MEDLINE | ID: mdl-27257786

ABSTRACT

Despite their instability in ethereal solvents, organotitanium hydride catalysts are successfully employed in catalysis at moderate to high temperatures (110 °C), even in the presence of alcohols. It is shown computationally (bond dissociation energy (BDE) analysis and energetic profile for regeneration) and experimentally (EPR studies and kinetic studies), with the specific example of hydrodefluorination (HDF), that despite the long standing belief, regeneration of Ti-H bonds from Ti-F bonds using silanes is endergonic. The resulting low concentration of Ti-H species is crucial for the catalytic stability of those systems. The resting state in the catalysis is a Ti-F species. The most promising silanes for regeneration are not the ones that have the strongest Si-F bond, but the ones that show the largest difference in Si-F and Si-H BDEs.

5.
J Neurosci ; 33(39): 15504-17, 2013 Sep 25.
Article in English | MEDLINE | ID: mdl-24068818

ABSTRACT

In the postsynaptic density of glutamatergic synapses, the discs large (DLG)-membrane-associated guanylate kinase (MAGUK) family of scaffolding proteins coordinates a multiplicity of signaling pathways to maintain and regulate synaptic transmission. Postsynaptic density-93 (PSD-93) is the most variable paralog in this family; it exists in six different N-terminal isoforms. Probably because of the structural and functional variability of these isoforms, the synaptic role of PSD-93 remains controversial. To accurately characterize the synaptic role of PSD-93, we quantified the expression of all six isoforms in the mouse hippocampus and examined them individually in hippocampal synapses. Using molecular manipulations, including overexpression, gene knockdown, PSD-93 knock-out mice combined with biochemical assays, and slice electrophysiology both in rat and mice, we demonstrate that PSD-93 is required at different developmental synaptic states to maintain the strength of excitatory synaptic transmission. This strength is differentially regulated by the six isoforms of PSD-93, including regulations of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor-active and inactive synapses, and activity-dependent modulations. Collectively, these results demonstrate that alternative combinations of N-terminal PSD-93 isoforms and DLG-MAGUK paralogs can fine-tune signaling scaffolds to adjust synaptic needs to regulate synaptic transmission.


Subject(s)
Guanylate Kinases/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/metabolism , Synaptic Transmission , Animals , Cells, Cultured , Gene Expression Regulation, Developmental , Guanylate Kinases/genetics , Hippocampus/cytology , Hippocampus/growth & development , Hippocampus/metabolism , Hippocampus/physiology , Intracellular Signaling Peptides and Proteins/genetics , Membrane Proteins/genetics , Mice , Neurons/metabolism , Neurons/physiology , Protein Isoforms/genetics , Protein Isoforms/metabolism , Rats , Rats, Wistar , Receptors, AMPA/genetics , Receptors, AMPA/metabolism , Transcription, Genetic
6.
Am J Pathol ; 183(2): 336-43, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23727348

ABSTRACT

Truncated forms of HER2, previously identified in subsets of HER2-positive breast cancer, originate from proteolytic extracellular domain (ECD) cleavage or alternative translation initiation. They lack ECD but may retain intracellular domain functionality, potentially associated with unfavorable prognosis, metastasis, and decreased sensitivity to antibody-based HER2-targeted therapy. To study the distribution of truncated HER2 in breast cancer, we detected loss of membrane-bound ECD independently of its molecular origin in paraffin sections, combining multispectral unmixing of chromogenic duplex IHC for HER2 ECD and intracellular domain with advanced image analysis. HER2 C-terminal fragment 611-transfected MCF7 and 4-aminophenylmercuric acetate-treated SKBR3 cell lines were used as controls. Applying a prototype work flow to whole sections, paired surgical resection/core needle biopsy samples, and paired samples from 69 patients of a phase 2 neoadjuvant clinical trial, we observed unexpected heterogeneity of ECD loss at the single-cell level, and in different areas of individual tumors, indicating that extent and localization of HER2 ECD loss add relevant information to averaging truncated HER2 across whole sections. We show acceptable run-to-run variation (coefficient of variation, <0.15), image analysis results in moderate agreement with conventional slide assessment (Cohen's κ = 0.59), and no obvious interference with previous HER2-ECD-targeted therapy. We conclude that duplex IHC and digital image processing extend current approaches of truncated HER2 detection.


Subject(s)
Breast Neoplasms/diagnosis , Receptor, ErbB-2/metabolism , Biopsy, Needle , Blotting, Western , Breast Neoplasms/therapy , Cell Line, Tumor , Chromogenic Compounds , Extracellular Space/metabolism , Feasibility Studies , Female , Humans , Image Processing, Computer-Assisted , Immunohistochemistry , Paraffin Embedding , Pilot Projects , Receptor, ErbB-2/antagonists & inhibitors
7.
J Pathol ; 229(4): 569-78, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23192518

ABSTRACT

Evaluation of specific lymphocyte subsets is important in understanding the microenvironment in cancer and holds promise as a prognostic parameter in invasive breast cancer. To address this, we used digital image analysis to integrate cell abundance, distance metrics, neighbourhood relationships and sample heterogeneity into comprehensive assessment of immune infiltrates. Lymphocyte and macrophage subpopulations were detected by chromogenic duplex immunohistochemistry for CD3/perforin and CD68/CD163 in samples of invasive breast cancer. The analysis workflow combined commercial and open-source software modules. We confirmed the accuracy of automated detection of cells with lymphoid morphology [concordance correlation coefficient (CCC), 0.92 for CD3(+) -T lymphocytes], whereas variable morphology limited automated classification of macrophages as distinct cellular objects (CCC, 0.43 for object-based detection; 0.79 for pixel-based area analysis). Using a supervised learning algorithm that clustered image areas according to lymphocyte abundance, grouping behaviour and distance to tumour cells, we identified recurrent infiltration patterns reflecting different grades of direct interaction between tumour and immune effector cells. The approach provided comprehensive visual and statistical assessment of the inflammatory tumour microenvironment and allowed quantitative estimation of heterogeneous immune cell distribution. Cases with dense lymphocytic infiltrates (8/33) contained up to 65% of areas in which observed distances between tumour and immune cells suggested a low chance of direct contact, indicating the presence of regions where tumour cells might be protected from immune attack. In contrast, cases with moderate (11/33) or low (14/33) lymphocyte density occasionally comprised areas of focally intense interaction, likely not to be captured by conventional scores. Our approach improves the conventional evaluation of immune cell density scores by translating objective distance metrics into reproducible, largely observer-independent interaction patterns.


Subject(s)
Image Processing, Computer-Assisted/methods , Inflammatory Breast Neoplasms/immunology , Macrophages/immunology , T-Lymphocytes/immunology , Tumor Microenvironment/immunology , Algorithms , Cluster Analysis , Female , Humans , Immunohistochemistry , Prognosis , Reproducibility of Results , Software
8.
Proc Natl Acad Sci U S A ; 109(40): E2717-25, 2012 Oct 02.
Article in English | MEDLINE | ID: mdl-23012412

ABSTRACT

Endocannabinoid signaling critically regulates emotional and motivational states via activation of cannabinoid receptor 1 (CB1) in the brain. The nucleus accumbens (NAc) functions to gate emotional and motivational responses. Although expression of CB1 in the NAc is low, manipulation of CB1 signaling within the NAc triggers robust emotional/motivational alterations related to drug addiction and other psychiatric disorders, and these effects cannot be exclusively attributed to CB1 located at afferents to the NAc. Rather, CB1-expressing neurons in the NAc, although sparse, appear to be critical for emotional and motivational responses. However, the cellular properties of these neurons remain largely unknown. Here, we generated a knock-in mouse line in which CB1-expressing neurons expressed the fluorescent protein td-Tomato (tdT). Using these mice, we demonstrated that tdT-positive neurons within the NAc were exclusively fast-spiking interneurons (FSIs). These FSIs were electrically coupled with each other, and thus may help synchronize populations/ensembles of NAc neurons. CB1-expressing FSIs also form GABAergic synapses on adjacent medium spiny neurons (MSNs), providing feed-forward inhibition of NAc output. Furthermore, the membrane excitability of tdT-positive FSIs in the NAc was up-regulated after withdrawal from cocaine exposure, an effect that might increase FSI-to-MSN inhibition. Taken together with our previous findings that the membrane excitability of NAc MSNs is decreased during cocaine withdrawal, the present findings suggest that the basal functional output of the NAc is inhibited during cocaine withdrawal by multiple mechanisms. As such, CB1-expressing FSIs are targeted by cocaine exposure to influence the overall functional output of the NAc.


Subject(s)
Cocaine , Interneurons/metabolism , Nucleus Accumbens/cytology , Receptor, Cannabinoid, CB1/metabolism , Signal Transduction/physiology , Substance Withdrawal Syndrome/physiopathology , Analysis of Variance , Animals , DNA Primers/genetics , Gene Knock-In Techniques , Immunohistochemistry , Male , Mice , Nucleus Accumbens/metabolism , Patch-Clamp Techniques , Receptor, Cannabinoid, CB1/genetics , Substance Withdrawal Syndrome/metabolism
9.
Chemistry ; 18(34): 10701-14, 2012 Aug 20.
Article in English | MEDLINE | ID: mdl-22777749

ABSTRACT

The hydrodefluorination (HDF) of fluoroalkenes in the presence of a variety of titanium catalysts was studied with respect to scope, selectivity, and mechanism. Optimization revealed that the catalyst requires low steric bulk and high electron density; secondary silanes serve as the preferred hydride source. A broad range of substrates yield partially fluorinated alkenes, such as previously unknown (Z)-1,2-(difluorovinyl)ferrocene. Mechanistic studies indicate a titanium(III) hydride as the active species, which forms a titanium(III) fluoride by H/F exchange with the substrate. The HDF step can follow both an insertion/elimination and a σ-bond metathesis mechanism; the E/Z selectivity is controlled by the substrate. The catalysts' ineffieciency towards fluoroallenes was rationalized by studying their reactivity towards Group 6 hydride complexes.

10.
Int J Cancer ; 131(7): 1621-32, 2012 Oct 01.
Article in English | MEDLINE | ID: mdl-22213219

ABSTRACT

The accuracy of common markers for PI3K/AKT and MAPK pathway activation in preclinical and clinical cancer biomarker studies depends on phosphoepitope stability and changes of phosphorylation under ischemia. Herein, we define conditions under which phosphoepitope-specific duplex immunohistochemistry (IHC) on formalin-fixed, paraffin-embedded tumor tissues reflects pathway activation in situ as accurately as possible, and identify activation patterns linked to mutational status, pathway dependency and tumor microenvironment in clinical tumor samples, cell culture and xenograft tissues. Systematically assessing robustness of pAKT, pERK1/2, pMEK1/2 and pmTOR detection and related markers in xenograft tissues exposed to ischemia, we show that control of preprocessing and ischemia times allows accurate interpretation of staining results. Phosphorylation patterns were then analyzed in 33 xenograft models and in 58 cases with breast cancer, including 21 paired samples of core-needle biopsies with corresponding mastectomy specimens, and 37 mastectomy samples obtained under rigorously controlled conditions minimizing ischemia time. Patterns of pAKT and pERK1/2 staining (predominant PI3K/AKT, predominant MAPK and concomitant activation) were associated with sensitivity to pathway inhibition and partially with the mutational status in cell lines and corresponding xenograft tumors. In contrast, no clear correlation between mutational status and staining patterns was observed in clinical breast cancer samples, suggesting that interaction with the human tumor microenvironment may interfere with the use of phosphoepitope-specific IHC as potential markers for pathway dependency. In contrast to core needle biopsies, surgically resected breast cancer samples showed evidence of severe signal changes comparable to those effects observed in xenograft tumors exposed to controlled ischemia.


Subject(s)
Cold Ischemia , Neoplasms/metabolism , Neoplasms/pathology , Signal Transduction , Tumor Microenvironment/immunology , Animals , Biopsy , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Line, Tumor , Female , Humans , Immunohistochemistry , Inflammation/immunology , Inflammation/pathology , Mice , Mice, SCID , Mitogen-Activated Protein Kinases/metabolism , Mutation , Neoplasms/genetics , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Transplantation, Heterologous
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