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Background: Primary progressive aphasia (PPA) and conditions that overlap with it can be accompanied by motor speech disorders. Recognition and understanding of motor speech disorders can contribute to a fuller clinical understanding of PPA and its management as well as its localisation and underlying pathology.

Aims: To review the types of motor speech disorders that may occur with PPA, its primary variants, and its overlap syndromes (progressive supranuclear palsy syndrome, corticobasal syndrome, motor neuron disease), as well as with primary progressive apraxia of speech.

Main Contribution: The review should assist clinicians’ and researchers’ understanding of the relationship between motor speech disorders and PPA and its major variants. It also highlights the importance of recognising neurodegenerative apraxia of speech as a condition that can occur with little or no evidence of aphasia.

Conclusion: Motor speech disorders can occur with PPA. Their recognition can contribute to clinical diagnosis and management of PPA and to understanding and predicting the localisation and pathology associated with PPA variants and conditions that can overlap with them.  相似文献   
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Most patients who die after traumatic brain injury (TBI) show evidence of ischemic brain damage. Nevertheless, it has proven difficult to demonstrate cerebral ischemia in TBI patients. After TBI, both global and localized changes in cerebral blood flow (CBF) are observed, depending on the extent of diffuse brain swelling and the size and location of contusions and hematoma. These changes vary considerably over time, with most TBI patients showing reduced CBF during the first 12 hours after injury, then hyperperfusion, and in some patients vasospasms before CBF eventually normalizes. This apparent neurovascular uncoupling has been ascribed to mitochondrial dysfunction, hindered oxygen diffusion into tissue, or microthrombosis. Capillary compression by astrocytic endfeet swelling is observed in biopsies acquired from TBI patients. In animal models, elevated intracranial pressure compresses capillaries, causing redistribution of capillary flows into patterns argued to cause functional shunting of oxygenated blood through the capillary bed. We used a biophysical model of oxygen transport in tissue to examine how capillary flow disturbances may contribute to the profound changes in CBF after TBI. The analysis suggests that elevated capillary transit time heterogeneity can cause critical reductions in oxygen availability in the absence of ‘classic'' ischemia. We discuss diagnostic and therapeutic consequences of these predictions.  相似文献   
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Regression calibration provides a way to obtain unbiased estimators of fixed effects in regression models when one or more predictors are measured with error. Recent development of measurement error methods has focused on models that include interaction terms between measured‐with‐error predictors, and separately, methods for estimation in models that account for correlated data. In this work, we derive explicit and novel forms of regression calibration estimators and associated asymptotic variances for longitudinal models that include interaction terms, when data from instrumental and unbiased surrogate variables are available but not the actual predictors of interest. The longitudinal data are fit using linear mixed models that contain random intercepts and account for serial correlation and unequally spaced observations. The motivating application involves a longitudinal study of exposure to two pollutants (predictors) – outdoor fine particulate matter and cigarette smoke – and their association in interactive form with levels of a biomarker of inflammation, leukotriene E4 (LTE 4, outcome) in asthmatic children. Because the exposure concentrations could not be directly observed, we used measurements from a fixed outdoor monitor and urinary cotinine concentrations as instrumental variables, and we used concentrations of fine ambient particulate matter and cigarette smoke measured with error by personal monitors as unbiased surrogate variables. We applied the derived regression calibration methods to estimate coefficients of the unobserved predictors and their interaction, allowing for direct comparison of toxicity of the different pollutants. We used simulations to verify accuracy of inferential methods based on asymptotic theory. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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BACKGROUND Cholesteryl ester storage disease(CESD)is a rare genetic disease.Its symptoms and severity are highly variable.CESD is a systemic disease that can lead to the accumulation of fat and inflammation in the liver,as well as gastrointestinal and cardiovascular disease.The majority of patients require liver transplantation due to decompensated cirrhosis.Enzyme replacement therapy has been approved based on a randomized trial.Our study aims to clinically and genetically evaluate two siblings with CESD who underwent liver transplantation,as well as their first-degree family members.CASE SUMMARY The siblings were compound heterozygous for the missense variant in LIPA exon 8,c.894G>A,(p.Gln298Gln)and a single base pair deletion,c.482del(p.Asn161Ilefs*19).Analyses of single nucleotide polymorphisms showed variants with an increased risk of fatty liver disease and fibrosis for both patients.Clinically,both patients show signs of recurrence of CESD in the liver after transplantation and additional gastrointestinal and cardiovascular signs of CESD.Three family members who were LIPA heterozygous had a lysosomal acid lipase activity below the reference value.One of these carriers,a seven-year-old boy,was found to have severe dyslipidemia and was subsequently treated with statins.CONCLUSION Our study underlines that CESD is a multi-organ disease,the progression of which may occur post-liver transplantation.Our findings underline the need for monitoring of complications and assessment of possible further treatment.  相似文献   
107.
Six months after a Comprehensive Abortion Care project was implemented in Phu-San Hospital, the main maternity hospital in Hai Phòng, northern Viet Nam, a study of quality of abortion services was carried out. The study explored the interaction between providers and women seeking abortion and how cultural values influenced quality of care. A quantitative and qualitative approach was employed: a three-part structured survey with 748 women before and after they had an abortion, 20 in-depth interviews with women just after abortion, seven informal interviews with health care staff and 100 participant observations. Both the women and the staff equated quality of care mainly with improved technical performance of abortion. Insufficient knowledge and skills had a negative impact on provision of information and good quality counselling in relation to understanding and uptake of contraception, treating reproductive tract infection and preventing post-abortion infection. To further improve abortion care in hospitals such as Phu-San, training programmes are needed that integrate counselling and clinical skills and address the cultural factors that hinder health staff and women from interacting in an equitable manner. A supportive supervisory system that holds health staff accountable for conducting high quality information and counselling sessions should also be established.  相似文献   
108.
OBJECTIVES: To evaluate the effect of estrogen replacement therapy or soy isoflavones supplement on endothelium-dependent relaxation in vitro and gene expression of endothelial nitric oxide synthase (eNOS) in cerebral arteries in a rabbit model of human hypercholesterolemia. STUDY DESIGN: Thirty-six female ovariectomized Watanabe heritable hyperlipidemic (WHHL) rabbits were randomised to treatment with 17beta-estradiol (17beta-E(2)), SoyLife 150 or control for 16 weeks. Ring segments of basilar artery (BA) and posterior cerebral artery (PCA) were mounted in myographs for isometric tension recordings. Concentration response curves to carbamylcholine chloride, sodium nitroprusside (SNP) and l-NAME were evaluated after precontraction with potassium. Total RNA was extracted, reverse transcribed and eNOS quantitated by real-time polymerase chain reaction (real-time PCR). RESULTS: Plasma cholesterol was significantly higher at termination in the SoyLife group (P<0.0001), whereas low-density lipoprotein (LDL) cholesterol was comparable in all treatment groups. Neither treatment influenced the endothelium-dependent responses to carbamylcholine chloride or l-NAME or the endothelium-independent response to SNP in any of the arteries. Correspondingly, eNOS mRNA was similarly expressed in all treatment groups in both arteries. CONCLUSIONS: Improvement of cerebral endothelial function by estrogen or soy isoflavones in ovariectomized WHHL rabbits is not supported by the present data. The findings may be unique to the WHHL rabbit in which the hypocholesterolemic effect of estrogens mediated by upregulation of liver LDL receptors is excluded.  相似文献   
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Estimates of the prevalence of congenital heart defects (CHD) have been published over many years and from many regions. As they are based on different definitions of which cases to include in the CHD prevalence, published prevalence estimates vary substantially. With the increasing use of echocardiography in neonatal intensive care, a patent ductus arteriosus (PDA) or flow over the atrial septum will often be visible. These findings may be coded as CHD at discharge and in this way falsely increase the CHD prevalence in the population. There are several purposes for which population‐based data on CHD may be used: etiology, planning of treatment, or obtain information on outcome, including mortality. For etiology studies, it is important to include terminations of pregnancy as well as all births with CHD. For mortality studies in live births, inclusion of preterm born infants with PDA will increase overall mortality of CHD. The Danish Register of Congenital Heart Disease is based on hospital discharge diagnoses and diagnoses from outpatient visits. To increase the validity of these data, extensive data cleaning has been carried out based on record review and knowledge on the discharge coding practice. We include PDA and atrial septal defects as CHD cases if these defects are still open 2 months after birth. International consensus on how to define CHD would improve the validity and comparability of epidemiological studies on CHD.  相似文献   
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