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61.
Francesco Cenni Simon-Henri Schless Lynn Bar-On Guy Molenaers Anja Van Campenhout Erwin Aertbeliën Herman Bruyninckx Britta Hanssen Kaat Desloovere 《Ultrasound in medicine & biology》2018,44(1):110-118
A clinically feasible method to reliably estimate muscle–tendon unit (MTU) lengths could provide essential diagnostic and treatment planning information. A 3-D freehand ultrasound (3-DfUS) method was previously validated for extracting in vivo medial gastrocnemius (MG) lengths, although the processing time can be considered substantial for the clinical environment. This investigation analyzed a quicker and simpler method using the US transducer as a spatial pointer (US-PaP), where the within-session reliability of extracting the muscle–tendon unit (MTU) and tendon lengths are estimated. MG MTU lengths were extracted in a group of 14 healthy adults using both 3-DfUS and US-PaP. Two consecutive acquisitions were performed per participant, and the data processed by two researchers independently. The intra-class correlation coefficients were above 0.97, and the standard error of measurements below 3.6?mm (1.5%). This investigation proposes that the simplified US-PaP method is a viable alternative for estimating MG MTU lengths. 相似文献
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63.
Background
Schistosomiasis affects the reproductive health of women. Described sequelae are ectopic pregnancy, infertility, abortion, and cervical lesions and symptoms mimicking cervical cancer and STIs. There are indications that cervical schistosomiasis lesions could become co-factors for viral infection such as HIV and HPV. 相似文献64.
Viola Oertel-Knöchel Britta Reinke Richard Feddern Annika Knake Christian Knöchel David Prvulovic Fabian Fußer Tarik Karakaya Deborah Loellgen Christine Freitag Johannes Pantel David E.J. Linden 《Journal of affective disorders》2013
Background
Episodic memory deficits affect the majority of patients with bipolar disorder (BD).Aims
The study investigates episodic memory performance through different approaches, including behavioural measures, physiological parameters, and the underlying functional activation patterns with functional neuroimaging (fMRI).Methods
26 Remitted BD patients and a matched group of healthy controls underwent a verbal episodic memory test together with monitored autonomic response, psychopathological ratings and functional magnetic resonance imaging (fMRI) during the verbal episodic memory test.Results
Compared to healthy controls, BD patients performed significantly worse during the episodic memory task. The results further indicate that verbal episodic memory deficits in BD are associated with abnormal functional activity patterns in frontal, occipital and limbic regions, and an increase in stress parameters.Limitations
We aimed to minimise sample heterogeneity by setting clear criteria for remission, based on the scores of a depression (BDI II) and mania scale (BRMAS) and on the DSM IV criteria. However, our patients were not symptom-free and scored higher on BDI II scores than the control group.Conclusions
The results are of interest for the treatment of cognitive symptoms in BD patients, as persistent cognitive impairment may hamper full rehabilitation. 相似文献65.
Satyan S. Kalkunte Stefan Neubeck Wendy E. Norris Shi-Bin Cheng Stefan Kostadinov Dang Vu Hoang Aftab Ahmed Ferdinand von Eggeling Zahir Shaikh James Padbury Goran Berg Anders Olofsson Udo R. Markert Surendra Sharma 《The American journal of pathology》2013,183(5):1425-1436
Preeclampsia is a major pregnancy complication with potential short- and long-term consequences for both mother and fetus. Understanding its pathogenesis and causative biomarkers is likely to yield insights for prediction and treatment. Herein, we provide evidence that transthyretin, a transporter of thyroxine and retinol, is aggregated in preeclampsia and is present at reduced levels in sera of preeclamptic women, as detected by proteomic screen. We demonstrate that transthyretin aggregates form deposits in preeclampsia placental tissue and cause apoptosis. By using in vitro approaches and a humanized mouse model, we provide evidence for a causal link between dysregulated transthyretin and preeclampsia. Native transthyretin inhibits all preeclampsia-like features in the humanized mouse model, including new-onset proteinuria, increased blood pressure, glomerular endotheliosis, and production of anti-angiogenic factors. Our findings suggest that a focus on transthyretin structure and function is a novel strategy to understand and combat preeclampsia.Preeclampsia occurs in 5% to 8% of pregnancies worldwide and is a major cause of fetal and maternal morbidity and mortality.1–3 It is a heterogeneous disease with varied presentations from mild self-limited hypertension and proteinuria to severe forms with significant end-organ dysfunction and HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets).3 Although the cause of preeclampsia and its appropriate treatment remain elusive, this syndrome has been proposed to reflect at least two stages of complications during pregnancy. These begin with preclinical manifestations at the maternal-fetal interface, followed by systemic clinical symptoms.1,2 Hypertension, proteinuria, and edema, with a variable degree of fetal growth restriction, are the cardinal features of preeclampsia.3 Because the placenta is the nutritional and immunological gateway to normal fetal development and pregnancy outcome, placenta-related events are believed to be central to the pathogenesis of this disease. Evidence exists for the release of disease-initiating molecules into maternal circulation that triggers the clinical symptoms.1,4 Placental and systemic anomalies reflected by circulating placental debris, inflammation, impaired remodeling of spiral arteries, placental hypoxia/ischemia, excess production of anti-angiogenic factors [soluble fms-like tyrosine kinase-1 (sFlt-1)], and soluble endoglin (sEng), and angiotensin receptor autoantibodies have all emerged as contributors to the pathophysiological characteristics of preeclampsia.2,4–14Preeclampsia has remained enigmatic because of lack of well-defined etiology and animal models. Although normal mice do not develop preeclampsia spontaneously, mouse models have been judged to be particularly useful to uterine diseases and pregnancy complications because many similarities in female reproduction and placentation have been identified between the two species.15 Moreover, their tractable genetics provide an effective way to probe mechanisms more deeply than many other species.15–17 We recently showed that sera from preeclamptic women could function as a source of novel causative factors that induced hypertension, proteinuria, and kidney pathological characteristics, as well as intrauterine growth restriction (IUGR), in IL-10−/− mice in a pregnancy-specific manner.18 IL-10 functions as a potent vascular and anti-inflammatory cytokine and has been shown to be present at significantly reduced levels in preeclampsia placental tissue.19,20 Preeclampsia serum (PES) was found to disrupt endovascular cross talk between trophoblasts and endothelial cells and to induce placental hypoxia and excess production of sFlt-1 and sEng,18 soluble factors known to precipitate maternal symptoms.21,22 These results from our serum-based humanized mouse model suggest that the pathophysiological characteristics of preeclampsia are more complex than previously thought and are likely to involve interactions and dysregulation of multiple factors. By using serum proteomic screening by surface-enhanced laser-desorption ionization-time-of-flight (SELDI-TOF), our results suggest that PES contains a reduced abundance of transthyretin, a plasma transport protein for the thyroid hormone, thyroxine, and retinol-binding protein.23 More important, transthyretin has been widely studied for its role in amyloid diseases associated with protein misfolding and aggregation, resulting in deposits of toxic, fibrillar aggregates in specific organs.24–26 Dysregulated or reduced transthyretin has also been implicated in Alzheimer disease, and overexpression of a wild-type human transthyretin transgene has been shown to ameliorate the disease in the transgenic murine model of human Alzheimer disease.27,28 Transthyretin in its native form assumes a homotetrameric quaternary configuration (approximately 14 kDa per monomer). Post-translational modifications of the monomer result in detection of several isoforms.29 Circulating transthyretin is also a validated marker of malnutrition and has a putative role in oocyte maturation and inflammation.30–32 Although the presence of transthyretin during implantation in mice and in the placenta and trophoblasts in humans has been reported,33,34 its functional role in normal pregnancy or adverse pregnancy outcomes has not been recognized. We hypothesize that transthyretin in preeclampsia is structurally and functionally dysregulated and contributes to the onset of this serious pregnancy complication. Herein, we present complementary in vitro and in vivo approaches, which show that endogenously altered transthyretin is a preeclampsia-causing agent and that native transthyretin has the ability to block the onset of preeclampsia-like features. 相似文献
66.
Parameswari Govindarajan Thaqif Khassawna Marian Kampschulte Wolfgang Böcker Britta Huerter Lutz Dürselen Miriam Faulenbach Christian Heiss 《International journal of experimental pathology》2013,94(6):387-398
Osteoporosis is one of the deleterious side effects of long-term glucocorticoid therapy. Since the condition is particularly aggressive in postmenopausal women who are on steroid therapy, in this study we have attempted to analyse the combined effect of glucocorticoid (dexamethasone) treatment and cessation of oestrogen on rat bone. The dual aim was to generate osteoporotic bone status in a short time scale and to characterise the combination of glucocorticoid–postmenopausal osteoporotic conditions. Sprague Dawley rats (N = 42) were grouped randomly into three groups: untreated control, sham-operated and ovariectomized–steroid (OVX-Steroid) rats. Control animals were euthanized with no treatment [Month 0 (M0)], while sham and OVX-Steroid rats were monitored up to 1 month (M1) and 3 months (M3) post laparotomy/post OVX-Steroid treatment. Histology, dual-energy X-ray absorptiometry (DXA), micro-computed tomography (micro-CT), and biomechanical and mRNA expression analysis of collagenous, non-collagenous matrix proteins and osteoclast markers were examined. The study indicated enhanced osteoclastogenesis and significantly lower bone mineral density (BMD) in the OVX-Steroid rats with Z-scores below −2.5, reduced torsional strength, reduced bone volume (BV/TV%), significantly enhanced trabecular separation (Tb.S), and less trabecular number (Tb.N) compared with sham rats. Osteoclast markers, cathepsin K and MMP 9 were upregulated along with Col1α1 and biglycan with no significant expression variation in fibronectin, MMP 14, LRP-5, Car II and TNC. These results show higher bone turnover with enhanced bone resorption accompanied with reduced torsional strength in OVX-Steroid rats; and these changes were attained within a short timeframe. This could be a useful model which mimics human postmenopausal osteoporosis that is associated with steroid therapy and could prove of value both in disease diagnosis and for testing generating and testing biological agents which could be used in treatment. 相似文献
67.
Angela Huttner Alice Bricheux Carianne J.M. Buurmeijer-van Dijk Matthew Harvey Alison Holmes Britta Lassmann Valéry Lavergne Alexandra Mailles Marc Mendelson Nicolas Muller Maurizio Sanguinetti Cynthia Sears Chrysanthi Skevaki Uzma Syed Salandra Thomas Talia H. Swartz Talia H. Swartz 《Clinical microbiology and infection》2021,27(5):704-707
BackgroundThough women increasingly make up the majority of medical-school and other science graduates, they remain a minority in academic biomedical settings, where they are less likely to hold leadership positions or be awarded research funding. A major factor is the career breaks that women disproportionately take to see to familial duties. They experience a related, but overlooked, hurdle upon their return: they are often too old to be eligible for ‘early-career researcher’ grants and ‘career-development’ awards, which are stepping stones to leadership positions in many institutions and which determine the demographics of their hierarchies for decades to come. Though age limits are imposed to protect young applicants from more experienced seniors, they have an unintended side effect of excluding returning workers, still disproportionately women, from the running.MethodsIn this joint effort by the European Society of Clinical Microbiology and Infectious Diseases, the Federation of European Microbiological Societies, the Infectious Disease Society of America, the International Society for Infectious Diseases and the Swiss Society for Infectious Diseases, we invited all European Congress of Clinical Microbiology and Infectious Diseases-affiliated medical societies and funding bodies to participate in a survey on current ‘early-career’ application restrictions and measures taken to provide protections for career breaks.RecommendationsThe following simple consensus recommendations are geared to funding bodies, academic societies and other organizations for the fair handling of eligibility for early-career awards: 1. Apply a professional, not physiological, age limit to applicants. 2. State clearly in the award announcement that career breaks will be factored into applicants' evaluations such that: ? Time absent is time extended: for every full-time equivalent of career break taken, the same full-time equivalent will be extended to the professional age limit. ? Opportunity costs will also be taken into account: people who take career breaks risk additional opportunity costs, with work that they did before the career break often being forgotten or poorly documented, particularly in bibliometric accounting. Although there is no standardized metric to measure additional opportunity costs, organizations should (a) keep in mind their existence when judging applicants' submissions, and (b) note clearly in the award announcement that opportunity costs of career breaks are also taken into account. 3. State clearly that further considerations can be undertaken, using more individualized criteria that are specific to the applicant population and the award in question.The working group welcomes feedback so that these recommendations can be improved and updated as needed. 相似文献
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69.
Jessica Langella Britta Magnuson Matthew D. Finkelman Robert Amato 《Journal of endodontics》2021,47(4):566-571
IntroductionThe spread of coronavirus disease 2019 (COVID-19) in the spring of 2020 resulted in the temporary suspension of elective dental procedures and clinical dental education in academic institutions. This study describes the use of the Tufts University School of Dental Medicine emergency dental clinic during the peak surge in COVID-19 cases in Massachusetts, highlighting the number of endodontic emergencies.MethodsAggregate data from clinical encounters and call records to an emergency triage phone line from March 30 through May 8, 2020, were used to describe the characteristics of dental emergencies, clinical encounters, and procedures performed.ResultsA total of 466 patient interactions occurred during this period, resulting in 199 patients advised by phone and 267 clinical encounters. The most common dental emergencies were severe dental pain from pulpal inflammation (27.7% of clinical encounters) followed by a surgical postoperative visit (13.1%). The most frequent procedures were extractions (13.9% of clinical encounters) and surgical follow-up (13.5%); 50.2% of the clinical encounters were categorized as aerosol generating, and 86.1% of encounters would have required treatment in a hospital emergency department if dental care was not available. There were no known transmissions of severe acute respiratory syndrome coronavirus-2 among clinic providers, patients, or staff during this period.ConclusionsThese results highlight the importance of endodontic diagnosis and treatment in the provision of emergency dental care during a pandemic and demonstrate that dental treatment can be provided in a manner that minimizes the risk of viral transmission, maintaining continuity of care for a large patient population. 相似文献
70.
Shirley K. Knauer Britta Unruhe Sarah Karczewski Rouven Hecht Verena Fetz Carolin Bier Sandra Friedl Barbara Wollenberg Ralph Pries Negusse Habtemichael Ulf‐Rüdiger Heinrich Roland H. Stauber 《Human mutation》2013,34(2):395-404
Survivin (BIRC5) is an acknowledged cancer therapy‐resistance factor and overexpressed in head and neck squamous cell carcinomas (HNSCC). Driven by its nuclear export signal (NES), Survivin shuttles between the nucleus and the cytoplasm, and is detectable in both cellular compartments in tumor biopsies. Although predominantly nuclear Survivin is considered a favorable prognostic disease marker for HNSCC patients, the underlying molecular mechanisms are not resolved. Hence, we performed immunohistochemical and mutational analyses using laser capture microdissection on HNSCC biopsies from patients displaying high levels of nuclear Survivin. We found somatic BIRC5 mutations, c.278T>C (p.Phe93Ser), c.292C>T (p.Leu98Phe), and c.288A>G (silent), in tumor cells, but not in corresponding normal tissues. Comprehensive functional characterization of the Survivin mutants by ectopic expression and microinjection experiments revealed that p.Phe93Ser, but not p.Leu98Phe inactivated Survivin's NES, resulted in a predominantly nuclear protein, and attenuated Survivin's dual cytoprotective activity against chemoradiation‐induced apoptosis. Notably, in xenotransplantation studies, HNSCC cells containing the p.Phe93Ser mutation responded significantly better to cisplatin‐based chemotherapy. Collectively, our results underline the disease relevance of Survivin's nucleocytoplasmic transport, and provide first evidence that genetic inactivation of Survivin's NES may account for predominantly nuclear Survivin and increased therapy response in cancer patients. 相似文献