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81.
Gotthardt M Welcke U Brandt D Tontsch D Barth PJ Schaefer J Hoeffken H Joseph K 《Clinical nuclear medicine》2000,25(6):414-420
Erdheim-Chester disease (ECD) is a rare disorder that has been reported fewer than 60 times in the literature. Although clinical findings seem to be specific at first sight, histologic classification remains unclear. It has not been decided whether ECD is part of the spectrum of histiocytoses or whether it may be a lipid storage disorder or even a primary macrophage cell disorder, although it does show a distinct histologic pattern. However, the clinical appearance alone shows several typical features, rendering the diagnosis very probable if present. This article illustrates the importance of bone scanning in ECD, because the scintigraphic pattern of involved skeletal sites may in themselves lead to the diagnosis. Several differential diagnoses are considered. The importance of bone scintigraphy as an imaging method in patients with an unclear diagnosis is discussed, as exemplary in ECD, as is its role for the detection of sites of skeletal involvement in other diseases. 相似文献
82.
83.
William P Howlett Sarah J Urasa Venance P Maro Richard W Walker Kajiru G Kilonzo Patrick J Howlett Marieke CJ Dekker 《African health sciences》2022,22(1):269
BackgroundThe burden of neurological disorders is large and altered by the HIV epidemic.ObjectivesWe describe the pattern of neurological disorders and their association with HIV infection in adult patients attending a consultant hospital in Northern Tanzania.MethodsIn this prospective cross-sectional study, we collected data on adult neurological referrals over a 6-year period between 2007–13. The odds of HIV infection, across neurological categories adjusted for age and sex, was calculated.ResultsOf 2037 participants, 54.8% were male and 45.2% were female. The median age of participants was 43 years. The results for HIV screening were available for 992/2037 (48.7%) patients, of whom 306 (30.8%) were seropositive. The most frequent neurological disorders were cerebrovascular disease (19.9%), paraplegia (13.6%), and peripheral neuropathies (8%). Taken together CNS infection accounted for 278/2037 (13.6%). The adjusted odds (aOR) of HIV infection was highest amongst infections; brain abscesses (aOR 107, 95% CI 35.1–470.4) and meningitis/encephalitis (aOR 40.1, 95% CI 13.6–172.9), but also raised in cerebrovascular disease, paraplegia, peripheral neuropathies, cranial nerve palsies, seizures, cerebllar disorders, movement disorders, motor neuron disease and headache.ConclusionThe main pattern of neurological disorders in Northern Tanzania is presented. The odds of HIV infection was highest in CNS infections and in a wide range of non-communicable neurological disorders. 相似文献
84.
Valerie J. Flaherman Amy S. Ginsburg Victoria Nankabirwa Augusto Braima da Sa Alvaro MedelHerrero Eric Schaefer Srijana Dongol Akina Shrestha Imran Nisar Muddassir Altaf Khushboo Liaquat Benazir Baloch Najeeb Rahman Yasir Shafiq Shabina Ariff Fyezah Jehan Susan B. Roberts 《Maternal & child nutrition》2022,18(4)
In low‐ and middle‐income countries (LMIC), growth impairment is common; however, the trajectory of growth over the course of the first month has not been well characterised. To describe newborn growth trajectory and predictors of growth impairment, we assessed growth frequently over the first 30 days among infants born ≥2000 g in Guinea‐Bissau, Nepal, Pakistan and Uganda. In this cohort of 741 infants, the mean birth weight was 3036 ± 424 g. For 721 (98%) infants, weight loss occurred for a median of 2 days (interquartile range, 1–4) following birth until weight nadir was reached 5.9 ± 4.3% below birth weight. At 30 days of age, the mean weight was 3934 ± 592 g. The prevalence of being underweight at 30 days ranged from 5% in Uganda to 31% in Pakistan. Of those underweight at 30 days of age, 56 (59%) had not been low birth weight (LBW), and 48 (50%) had reached weight nadir subsequent to 4 days of age. Male sex (relative risk [RR] 2.73 [1.58, 3.57]), LBW (RR 6.41 [4.67, 8.81]), maternal primiparity (1.74 [1.20, 2.51]) and reaching weight nadir subsequent to 4 days of age (RR 5.03 [3.46, 7.31]) were highly predictive of being underweight at 30 days of age. In this LMIC cohort, country of birth, male sex, LBW and maternal primiparity increased the risk of impaired growth, as did the modifiable factor of delayed initiation of growth. Interventions tailored to infants with modifiable risk factors could reduce the burden of growth impairment in LMIC. 相似文献
85.
Swagatha Ghosh Sayan Mondal Keerti Yadav Shantanu Aggarwal Wayne F. Schaefer Chandrabhas Narayana Ramaswamy Subramanian 《RSC advances》2022,12(31):20296
Biliverdin IX-alpha (BV), a tetrapyrrole, is found ubiquitously in most living organisms. It functions as a metabolite, pigment, and signaling compound. While BV is known to bind to diverse protein families such as heme-metabolizing enzymes and phytochromes, not many BV-bound lipocalins (ubiquitous, small lipid-binding proteins) have been studied. The molecular basis of binding and conformational selectivity of BV in lipocalins remains unexplained. Sandercyanin (SFP)–BV complex is a blue lipocalin protein present in the mucus of the Canadian walleye (Stizostedion vitreum). In this study, we present the structures and binding modes of BV to SFP. Using a combination of designed site-directed mutations, X-ray crystallography, UV/VIS, and resonance Raman spectroscopy, we have identified multiple conformations of BV that are stabilized in the binding pocket of SFP. In complex with the protein, these conformers generate varied spectroscopic signatures both in their absorption and fluorescence spectra. We show that despite no covalent anchor, structural heterogeneity of the chromophore is primarily driven by the D-ring pyrrole of BV. Our work shows how conformational promiscuity of BV is correlated to the rearrangement of amino acids in the protein matrix leading to modulation of spectral properties.Biliverdin IX-alpha undergoes rotation around the D-ring pyrrole and displays a broad far-red absorbance on binding to monomeric Sandercyanin variant (orange) compared to the wild-type tetrameric protein (cyan). 相似文献
86.
Ricard Navins Giovanni Oriolo Igor Horrillo Myriam Cavero Bruno Aouizerate Martin Schaefer Lucile Capuron J Javier Meana Rocio Martin-Santos 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2022,25(6):468
BackgroundThe relationship between antidepressant response and glial, inflammatory, and metabolic markers is poorly understood in depression. This study assessed the ability of biological markers to predict antidepressant response in major depressive disorder (MDD).MethodsWe included 31 MDD outpatients treated with escitalopram or sertraline for 8 consecutive weeks. The Montgomery-Åsberg Depression Rating Scale (MADRS) was administered at baseline and at week 4 and 8 of treatment. Concomitantly, blood samples were collected for the determination of serum S100B, C-reactive protein (CRP), and high-density lipoprotein cholesterol (HDL)-C levels. Treatment response was defined as ≥50% improvement in the MADRS score from baseline to either week 4 or 8. Variables associated with treatment response were included in a linear regression model as predictors of treatment response.ResultsTwenty-seven patients (87%) completed 8 weeks of treatment; 74% and 63% were responders at week 4 and 8, respectively. High S100B and low HDL-C levels at baseline were associated with better treatment response at both time points. Low CRP levels were correlated with better response at week 4. Multivariate analysis showed that high baseline S100B levels and low baseline HDL-C levels were good predictors of treatment response at week 4 (R2 = 0.457, P = .001), while S100B was at week 8 (R2 = 0.239, P = .011). Importantly, baseline S100B and HDL-C levels were not associated with depression severity and did not change over time with clinical improvement.ConclusionsSerum S100B levels appear to be a useful biomarker of antidepressant response in MDD even when considering inflammatory and metabolic markers. 相似文献
87.
W L Cullinan E Erdos R Schaefer M E Tekieli 《Journal of speech and hearing research》1977,20(4):742-751
Recent findings indicate that the presence of formant transitions aids the perception of the order of stimuli in repeating sequences of vowels or consonant-vowel (CV) syllables. In this study, 12 listeners reported the perceived order of four vowels or CVs in repeating sequences. Stimuli ranged in duration from 75 to 300 msec in 25-msec steps. Four stimulus sequences were used (1) varying vowels (Vv), (2) CVs with varying consonants but a constant vowel (CvVc), (3) CVs with a constant consonant but varying vowels (CcVv), (4) CVs with consonants and vowels varying (CvVv). Percentage of correct identification of order was significantly higher and mean threshold duration significantly lower for the CvVv and CvVc conditions than for the Vv condition. Mean number of sequences per response was significantly smaller for the CvVv condition than for the other conditions. Threshold durations ranged from 100 msec for the CvVv sequences to 135 msec for the Vv sequences. Ordering performance was nearly perfect for stimulus durations of about 225 to 250 msec. The results support the hypothesis that as stimuli in repeating sequences more closely resemble connected speech, listeners can more easily correctly identify the order of the stimuli. 相似文献
88.
Dozent Dr. Hans Schaefer 《Journal of molecular medicine (Berlin, Germany)》1941,20(9):209-212
Ohne ZusammenfassungNach einem Vortrag, gehalten am 10. Dezember 1940 vor der Medizinischen Gesellschaft in Gießen. 相似文献
89.
90.
C. Rousselle J.N. Ormsby B. Schaefer A. Lampen T. Platzek K. Hirsch-Ernst M. Warholm A. Oskarsson P.J. Nielsen M.L. Holmer C. Emond 《Regulatory toxicology and pharmacology : RTP》2013,65(1):7-11
The French Agency for Food, Environmental and Occupational Health and Safety (Anses) hosted a two-day workshop on Endocrine Disruptors: Exposure and Potential Impact on Consumers Health, bringing together participants from international organizations, academia, research institutes and from German, Swedish, Danish and French governmental agencies. The main objective of the workshop was to share knowledge and experiences on endocrine disruptors (ED) exposure and potential impact on consumers’ health, to identify current risk assessment practices and knowledge gaps and issue recommendations on research needs and future collaboration. The following topics were reviewed: (1) Definition of ED, (2) endpoints to be considered for Risk assessment (RA) of ED, (3) non-monotonic dose response curves, (4) studies to be considered for RA (regulatory versus academic studies), (5) point of departure and uncertainty factors, (6) exposure assessment, (7) regulatory issues related to ED. The opinions expressed during this workshop reflect day-to-day experiences from scientists, regulators, researchers, and others from many different countries in the fields of risk assessment, and were regarded by the attendees as an important basis for further discussions. Accordingly, the participants underlined the need for more exchange in the future to share experiences and improve the methodology related to risk assessment for endocrine disrupters. 相似文献