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A personal narrative is presented which explores the author's experience of being a missionary doctor in Liberia.

Background: Decision support systems (DSSs) for suggesting optimal treatments for individual patients with low back pain (LBP) are currently insufficiently accurate for clinical application. Most of the input provided to train these systems is based on patient-reported outcome measures. However, with the appearance of electronic health records (EHRs), additional qualitative data on reasons for referrals and patients' goals become available for DSSs. Currently, no decision support tools cover a wide range of biopsychosocial factors, including referral letter information to help clinicians triage patients to the optimal LBP treatment., Objective: The objective of this study was to investigate the added value of including qualitative data from EHRs and referral letters to the accuracy of a quantitative DSS for patients with LBP., Methods: A retrospective study was conducted in a clinical cohort of Dutch patients with LBP. Patients filled out a baseline questionnaire about demographics, pain, disability, work status, quality of life, medication, psychosocial functioning, comorbidity, history, and duration of pain. Referral reasons and patient requests for help (patient goals) were extracted via natural language processing (NLP) and enriched in the data set. For decision support, these data were considered independent factors for triage to neurosurgery, anesthesiology, rehabilitation, or minimal intervention. Support vector machine, k-nearest neighbor, and multilayer perceptron models were trained for 2 conditions: with and without consideration of the referral letter content. The models' accuracies were evaluated via F1-scores, and confusion matrices were used to predict the treatment path (out of 4 paths) with and without additional referral parameters., Results: Data from 1608 patients were evaluated. The evaluation indicated that 2 referral reasons from the referral letters (for anesthesiology and rehabilitation intervention) increased the F1-score accuracy by up to 19.5% for triaging. The confusion matrices confirmed the results., Conclusions: This study indicates that data enriching by adding NLP-based extraction of the content of referral letters increases the model accuracy of DSSs in suggesting optimal treatments for individual patients with LBP. Overall model accuracies were considered low and insufficient for clinical application., (©Sebastian Fudickar, Carsten Bantel, Jannik Spieker, Heinrich Töpfer, Patrick Stegeman, Henrica R Schiphorst Preuper, Michiel F Reneman, André P Wolff, Remko Soer. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 30.01.2024.)

Aims: Aim of the current study was to describe the prevalence, incidence, and severity of diabetes mellitus type 2 (T2D) in a cohort of older men and women aged 60 years and above over the course of on average 7 years, since longitudinal data on this topic are scarce for this age group in Germany., Methods: Baseline data of 1671 participants of the Berlin Aging Study II (BASE-II; 68.8 ± 3.7 years) and follow-up data assessed 7.4 ± 1.5 years later were analysed. The BASE-II is an exploratory, observational study on cross-sectional and longitudinal data of an older population. T2D was diagnosed based on self-report, antidiabetic medication use and laboratory parameters. T2D severity was determined by the diabetes complications severity index (DCSI). Prognostic capacity of laboratory parameters was evaluated., Results: The proportion of participants with T2D increased from 12.9% (37.3% women) at baseline to 17.1% (41.1% women) with 74 incident cases and 22.2% not being aware of the disease at follow-up. The incidence rate is 10.7 new T2D diagnoses per 1000 person-years. More than half of the 41 newly identified incident T2D cases were diagnosed solely by the 2 h-plasma glucose test (OGTT) and diagnosis based on OGTT as the only criterion among incident cases was found more frequently in women (p = 0.028). T2D severity expressed by the DCSI significantly increased from baseline to follow-up (mean DCSI 1.1 ± 1.2 vs. 2.0 ± 1.8; range 0-5 vs. 0-6). Cardiovascular complications had the highest impact (43.2% at baseline and 67.6% at follow-up)., Conclusions: A comprehensive picture of T2D with respect to prevalence, incidence, and severity in older people of the Berlin Aging Study II is provided., (© 2023 The Authors. Diabetic Medicine published by John Wiley & Sons Ltd on behalf of Diabetes UK.)

Background: Patients with Type 2 diabetes mellitus (T2D) are at risk for micro- and macrovascular complications. Implementable risk scores are needed to improve targeted prevention for patients that are particularly susceptible to complications. The epigenetic clock estimates an individual's biological age using DNA methylation profiles., Methods: In this study, we examined older adults of the Berlin Aging Study II that were reexamined on average 7.4 years after baseline assessment as part of the GendAge study. DNA methylation age (DNAmA) and its deviation from chronological age DNAmA acceleration (DNAmAA) were calculated with the 7-CpG clock (available at both timepoints, n = 1,071), Horvath's clock, Hannum's clock, PhenoAge and GrimAge (available at follow-up only, n = 1,067). T2D associated complications were assessed with the Diabetes Complications Severity Index (DCSI)., Results: We report on a statistically significant association between oral glucose tolerance test results and Hannum and PhenoAge DNAmAA. PhenoAge was also associated with fasting glucose. In contrast, we found no cross-sectional association after covariate adjustment between DNAmAA and a diagnosis of T2D. However, longitudinal analyses showed that every additional year of 7-CpG DNAmAA at baseline increased the odds for developing one or more additional complications or worsening of an already existing complication during the follow-up period by 11% in male participants with T2D. This association persisted after covariate adjustment (OR = 1.11, p = 0.045, n = 56)., Conclusion: Although our results remain to be independently validated, this study shows promising evidence of utility of the 7-CpG clock in identifying patients with diabetes who are at high risk for developing complications., (© 2023. The Author(s).)

There is ample evidence that cholinergic actions affect the health status of bones in vertebrates including man. Nicotine smoking, but also exposure to pesticides or medical drugs point to the significance of cholinergic effects on bone status, as reviewed here in Introduction. Then, we outline processes of endochondral ossification, and review respective cholinergic actions. In Results, we briefly summarize our in vivo and in vitro studies on bone development of chick and mouse [1,2], including (i) expressions of cholinergic components (AChE, BChE, ChAT) in chick embryo, (ii) characterisation of defects during skeletogenesis in prenatal ChE knockout mice, (iii) loss-of-function experiments with beads soaked in cholinergic components and implanted into chicken limb buds, and finally (iv) we use an in vitro mesenchymal 3D-micromass model that mimics cartilage and bone formation, which also had revealed complex crosstalks between cholinergic, radiation and inflammatory mechanisms [3]. In Discussion, we evaluate non-cholinergic actions of cholinesterases during bone formation by considering: (i) how cholinesterases could function in adhesive mechanisms; (ii) whether and how cholinesterases can form bone-regulatory complexes with alkaline phosphatase (ALP) and/or ECM components, which could regulate cell division, migration and adhesion. We conclude that cholinergic actions in bone development are driven mainly by classic cholinergic, but non-neural cycles (e.g., by acetylcholine); in addition, both cholinesterases can exert distinct ACh-independent roles. Considering their tremendous medical impact, these results bring forward novel research directions that deserve to be pursued., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Most components of the cholinergic system are detected in skeletogenic cell types in vitro, yet the function of this system in skeletogenesis remains unclear. Here, we analyzed endochondral ossification in mutant murine fetuses, in which genes of the rate-limiting cholinergic enzymes acetyl- (AChE), or butyrylcholinesterase (BChE), or both were deleted (called here A-B+, A+B-, A-B-, respectively). In all mutant embryos bone growth and cartilage remodeling into mineralizing bone were accelerated, as revealed by Alcian blue (A-blu) and Alizarin red (A-red) staining. In A+B- and A-B- onset of mineralization was observed before E13.5, about 2 days earlier than in wild type and A-B+ mice. In all mutants between E18.5 to birth A-blu staining disappeared from epiphyses prematurely. Instead, A-blu+ cells were dislocated into diaphyses, most pronounced so in A-B- mutants, indicating additive effects of both missing ChEs in A-B- mutant mice. The remodeling effects were supported by in situ hybridization (ISH) experiments performed on cryosections from A-B- mice, in which Ihh, Runx2, MMP-13, ALP, Col-II and Col-X were considerably decreased, or had disappeared between E18.5 and P0. With a second approach, we applied an improved in vitro micromass model from chicken limb buds that allowed histological distinction between areas of cartilage, apoptosis and mineralization. When treated with the AChE inhibitor BW284c51, or with nicotine, there was decrease in cartilage and accelerated mineralization, suggesting that these effects were mediated through nicotinic receptors (α7-nAChR). We conclude that due to absence of either one or both cholinesterases in KO mice, or inhibition of AChE in chicken micromass cultures, there is increase in cholinergic signalling, which leads to increased chondroblast production and premature mineralization, at the expense of incomplete chondrogenic differentiation. This emphasizes the importance of cholinergic signalling in cartilage and bone formation., Competing Interests: The authors have declared that no competing interests exist.

Formation of the vertebrate limb presents an excellent model to analyze a non-neuronal cholinergic system (NNCS). Here, we first analyzed the expression of acetylcholinesterase (AChE) by IHC and of choline acetyltransferase (ChAT) by ISH in developing embryonic chicken limbs (stages HH17-37). AChE outlined formation of bones, being strongest at their distal tips, and later also marked areas of cell death. At onset, AChE and ChAT were elevated in two organizing centers of the limb anlage, the apical ectodermal ridge (AER) and zone of polarizing activity (ZPA), respectively. Thereby ChAT was expressed shortly after AChE, thus strongly supporting a leading role of AChE in limb formation. Then, we conducted loss-of-function studies via unilateral implantation of beads into chicken limb anlagen, which were soaked in cholinergic components. After varying periods, the formation of cartilage matrix and of mineralizing bones was followed by Alcian blue (AB) and Alizarin red (AR) stainings, respectively. Both acetylcholine (ACh)- and ChAT-soaked beads accelerated bone formation in ovo. Notably, inhibition of AChE by BW284c51, or by the monoclonal antibody MAB304 delayed cartilage formation. Since bead inhibition of BChE was mostly ineffective, an ACh-independent action during BW284c51 and MAB304 inhibition was indicated, which possibly could be due to an enzymatic side activity of AChE. In conclusion, skeletogenesis in chick is regulated by an ACh-dependent cholinergic system, but to some extent also by an ACh-independent aspect of the AChE protein., Competing Interests: The authors have declared that no competing interests exist.

Allergic contact dermatitis is a delayed T-cell mediated allergic response associated with relevant social and economic impacts. Animal experiments (e.g. the local lymph node assay) are still supplying most of the data used to assess the sensitization potential of new chemicals. However, the 7th amendment to the EU Cosmetic Directive have introduced a testing ban for cosmetic ingredients after March 2013. We have developed and optimized a stable and reproducible in vitro protocol based on human peripheral blood monocyte derived dendritic cells to assess the sensitization potential of chemicals. To evaluate the transferability and the predictivity of this PBMDCs based test protocol, a ring study was organized with five laboratories using seven chemicals with a known sensitization potential (one none-sensitizer and six sensitizers, including one pro-hapten). The results indicated that this optimized test protocol could be successfully transferred to all participating laboratories and allowed a correct assessment of the sensitization potential of the tested set of chemicals. This should allow a wider acceptance of PBMDCs as a reliable test system for the detection of human skin sensitizers and the inclusion of this protocol in the toolbox of in vitro methods for the evaluation of the skin sensitization potential of chemicals., (Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Allergic contact dermatitis is a delayed T-cell mediated allergic response associated with relevant social and economic impacts. Animal experiments (e.g. the local lymph node assay) are still supplying most of the data used to assess the sensitization potential of new chemicals. However, the 7th amendment to the EU Cosmetic Directive will introduce a testing ban for cosmetic ingredients after 2013. In vitro alternative methods are thus being actively developed. Although promising results have been obtained with cell lines, their reduced functionality and inherent genomic instability led us to reinvestigate the use of peripheral blood monocyte-derived dendritic cells (PBMDCs) for the establishment of a reliable in vitro sensitization test. To solve the issues associated with the use of primary cells, the culture and exposure conditions (cytokine concentrations, incubation time, readout, pooled vs. single donors and cytotoxicity) were re-assessed and optimized. Here we propose a stable and reproducible protocol based on PBMDCs. This should allow a wider acceptance of PBMDCs as a reliable test system for the detection of human skin sensitizers and the inclusion of this protocol in an integrated testing strategy., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

The long-acting antibiotic tulathromycin is on the marked for treatment of pulmonary infection of cattle, swine and horses. To measure disposition and distribution of tulathromycin in foals, a high throughput method was developed for horse plasma (calibration range: 0.006-0.8 microg/mL) and broncho-alveolar cells (calibration range: 0.1-4.0 microg/10(9)cells) using tandem mass spectrometry. Tulathromycin was extracted from plasma and broncho-alveolar fluid using cation exchange cartridges with acetonitrile/ammonia (95:5, v/v). The chromatography was performed isocratically with a mobile phase consisting of 5 mM ammonium formiate buffer/acetonitrile (30:70, v/v). The mass spectrometer operated in selected ion mode with atmospheric pressure chemical ionization to monitor the respective MH+ ions m/z 577.3 for tulathromycin and m/z 679.3 for the internal standard roxithromycin. All quality parameters fulfilled the international criteria for bioanalytical method validation and were successfully applied to the determination of tulathromycin in plasma of foals and broncho-alveolar cells. In foals, tulathromycin after intramuscular administration was rapidly absorbed, widely distributed and slowly eliminated. It cumulated manifold in broncho-alveolar cells.

The immunogenicity, tolerability and interchangeability of two hepatitis A vaccines, Vaqta (Merck and Co.) and Havrix (SmithKline) were studied in a randomized, crossover, controlled clinical trial. Vaccine was administered to 201 volunteers at 0 and 26 weeks in one of four vaccine regimens: Havrix-Havrix; Havrix-Vaqta; Vaqta-Havrix or Vaqta-Vaqta. Seroconversion rates (>/=10 mIU/ml) for those whose first dose was Vaqta or Havrix, respectively, were: 41/96 (43%) versus 30/95 (32%) (P=0.15) at 2 weeks and 91/98 (93%) versus 84/97 (87%) (P=0.43) at 4 weeks, and 100% at 26 weeks. Geometric mean concentrations (GMC) of total antibody to hepatitis A virus (anti-HAV) for Vaqta and Havrix were 189 and 114 mIU/ml (P=0.011) at 4 weeks and 234 and 136 mIU/ml (P<0.001) at 26 weeks. At 30 weeks, the GMC after two doses of Havrix was 2612 mIU/ml compared with 5497 after two doses of Vaqta (P<0.001). The GMC in the Havrix-Vaqta group was 5672 mIU/ml compared with 3077 mIU/ml in the Vaqta-Havrix group (P<0.001). Less than half of vaccine recipients reported tenderness or pain. In this study, seroconversion rates of the two vaccines were similar. Vaqta produces significantly higher anti-HAV antibody than Havrix. Crossover immunization is well tolerated and results in high antibody concentrations, especially when Vaqta is the booster dose. The significance of higher anti-HAV antibody concentrations in terms of long-term protection is unknown.

Susceptibility of New World waterfowl to the Lake Andes strain of duck plague virus (DPV) was assessed by intramuscular inoculation of adult muscovies (Cairina moschata), mallards (Anas platyrhynchos), Canada geese (Branta canadensis), wood ducks (Aix sponsa), redheads (Aythya americana), gadwalls (Anas strepera), blue-winged teal (Anas discors), and pintails (Anas acuta). The relative virulence of DPV strains isolated from five United States and one Canadian location was established in muscovies, mallards, and Canada geese. Differences in DPV strain virulence were detected by formation of plaques in cell culture. Two strains that consistently formed plaques killed adult mallards while non-plaque forming strains killed hatchling but not adult mallards. Based on mortality after exposure to the Lake Andes strain, blue-winged teal, then wood ducks and redheads were highly susceptible, muscovies and gadwalls moderately susceptible, mallards and Canada geese less susceptible, and pintails the least susceptible. Mean death times were significantly (P < 0.01) different between adult muscovies (4.5 days) versus mallards and Canada geese (5.8 days each). Mean death time of the virulent Lake Andes and Minnesota strains were shorter (P < 0.05) than for the other four, less virulent DPV strains. Four of the less virulent strains killed hatchling but not adult mallards. Susceptibility to mortality was dependent upon age and route of inoculation. The intramuscular route of inoculation required the least amount of virus to kill mallard and muscovy ducks, the intranasal and conjunctival routes required more virus, and the oral route the most virus. This study was conducted from 1974 to 1977 between the months of September and April, with the exception of two titrations conducted in early May at the University of Wisconsin Department of Veterinary Science and the Charmany research facility of the University of Wisconsin-Madison.

Herpesvirus sylvilagus was inoculated into five cottontail rabbits (Sylvilagus floridanus) at various stages of pregnancy; they subsequently had litters in the laboratory. Three other cottontails chronically infected with the virus were bred and bore young in large outdoor pens. Thirty-four living neonates and dead fetuses were weighed, measured and aseptically necropsied. A total of 31 liver, spleen and kidney samples, 16 lymph node, 28 heart and 10 brain samples were collected and processed for inoculation into rabbit kidney cell cultures to attempt virus isolation. Virus was not detected in the 147 tissue samples tested. Pre-conception viremias ranged from 10-21 plaque-forming units per 0.5 ml. Virus isolation was attempted from 26 oral and lacrymal, 23 genital, nine urine and fecal, and four milk and male ejaculate samples from eight infected rabbits. Virus was recovered from two salivary samples from the same rabbit. Triamcinolone acetonide administered daily for four days to five rabbits did not stimulate excretion of virus.

A serologic survey of a wild cottontail rabbit (Sylvilagus floridanus) population in southern Wisconsin was conducted from November-March, 1971-72 and November-April, 1972-73, to determine prevalence of antibody against Herpesvirus sylvilagus. Flea burdens on each live-trapped cottontail were quantified by species. All but six of the 5029 fleas collected were Cediopsylla simplex. No correlation was found between flea infestation and viral antibody. Of 101 cottontail rabbits trapped, only six had specific antibody as determined by plaque neutralization in rabbit kidney cell culture. Three of the six developed antibody between January and March of the trapping season. Blood samples from 46 captured rabbits were negative for virus.

The vector potential of the rabbit flea (Cediopsylla simplex) and a mosquito (Aedes triseriatus) was investigated for Herpesvirus sylvilagus transmission among cottontail rabbits (Sylvilagus floridanus). Twelve groups of 12-50 fleas were fed on three viremic cottontails for 2-21 days before transfer to 12 susceptible rabbits. Standard interrupted feeding trials employed five groups of 6-12 mosquitoes, two viremic donor cottontails anf five healthy recipients. No evidence of virus was detected from recipients' blood nor did they develop specific antibody. Virus acquisition and persistence in the insects was evaluated by attempting to recover the virus from 19 pools of mosquitoes engorged on viremic blood and 36 pools of engorged fleas or those living on viremic hosts for 1-21 days. Results were negative.