Photon Counting Computed Tomography with the Radiation Dose of a Chest X-Ray: Feasibility and Diagnostic Yield.

INTRODUCTION: Photon counting (PC) detectors allow a reduction of the radiation dose in CT. Chest X-ray (CXR) is known to have a low sensitivity and specificity for detection of pneumonic infiltrates. The aims were to establish an ultra-low-dose CT (ULD-CT) protocol at a PC-CT with the radiation dose comparable to the dose of a CXR and to evaluate its clinical yield in patients with suspicion of pneumonia. METHODS: A ULD-CT protocol was established with the aim to meet the radiation dose of a CXR. In this retrospective study, all adult patients who received a ULD-CT of the chest with suspected pneumonia were included. Radiation exposure of ULD-CT and CXR was calculated. The clinical significance (new diagnosis, change of therapy, additional findings) and limitations were evaluated by a radiologist and a pulmonologist considering previous CXR and clinical data. RESULTS: Twenty-seven patients (70% male, mean age 68 years) were included. With our ULD-CT protocol, the radiation dose of a CXR could be reached (mean radiation exposure 0.11 mSv). With ULD-CT, the diagnosis changed in 11 patients (41%), there were relevant additional findings in 4 patients (15%), an infiltrate (particularly fungal infiltrate under immunosuppression) could be ruled out with certainty in 10 patients (37%), and the therapy changed in 10 patients (37%). Two patients required an additional CT with contrast medium to rule out a pulmonary embolism or pleural empyema. CONCLUSIONS: With ULD-CT, the radiation dose of a CXR could be reached while the clinical impact is higher with change in diagnosis in 41%.

Drug Safety Profiles of Geriatric Patients Referred to Consultation Psychiatry in the Emergency Department-A Retrospective Cohort Study.

OBJECTIVE: Geriatric patients account for a significant proportion of the collective treated by psychiatric consultation service in hospitals. In the Emergency Department (ED), psychotropic drugs are frequently recommended, notwithstanding their extensive side-effect profiles. This study sought to investigate medication safety of geriatric patients referred to psychiatric consultation service in the ED. METHODS: Medication lists of 60 patients from the general internal medicine and trauma surgery EDs referred to psychiatric consultation service were analyzed. Utilizing PRISCUS list and Fit fOR The Aged (FORTA) classification, prescriptions of potentially inappropriate medications (PIMs) were assessed. RESULTS: 84 drugs were newly prescribed following psychiatric consultations. The total number of drugs per patient was 5.4 ± 4.2 before psychiatric consultation and 6.5 ± 4.2 thereafter (p < .001). 22.6 % of the newly recommended drugs were PIMs according to the PRISCUS list, while 54.8 % were designated as therapeutic alternatives to PIMs. 54.8 % and 20.2 % of the newly recommended drugs were FORTA category C and D drugs, respectively. An average of 1.2 ± 1.7 drug-drug interactions (DDIs) existed before psychiatric consultation and 1.3 ± 1.9 DDIs thereafter (p = .08). CONCLUSION: The majority of newly recommended drugs by psychiatric consultation service in the ED were designated as suitable therapeutic alternatives to PIMs according to the PRISCUS list, but had comparatively unfavorable ratings according to the FORTA classification, demonstrating discrepancies between these two PIM classification systems. Physicians delivering psychiatric consultation services in the ED should not solely rely on one PIM classification system.

[Raw meat, lots of problems: rare infection in a patient after mechanical valve replacement and liver transplantation]. / Rohes Fleisch, viele Probleme: seltene Infektion bei einem Patienten nach mechanischem Klappenersatz und Lebertransplantation.

We report about a 43-year-old man who presented to the emergency department in septic shock with nonspecific gastrointestinal symptoms. Sonography and computed tomography (CT) could not identify the location of the infection in the patient who had undergone liver transplantation and has a mechanical mitral valve. Blood cultures were positive for Listeria monocytogenes. Transesophageal echocardiography showed prosthetic endocarditis. The findings regressed markedly under ampicillin.

Myeloid-derived growth factor (C19orf10) mediates cardiac repair following myocardial infarction.

Paracrine-acting proteins are emerging as a central mechanism by which bone marrow cell-based therapies improve tissue repair and heart function after myocardial infarction (MI). We carried out a bioinformatic secretome analysis in bone marrow cells from patients with acute MI to identify novel secreted proteins with therapeutic potential. Functional screens revealed a secreted protein encoded by an open reading frame on chromosome 19 (C19orf10) that promotes cardiac myocyte survival and angiogenesis. We show that bone marrow-derived monocytes and macrophages produce this protein endogenously to protect and repair the heart after MI, and we named it myeloid-derived growth factor (MYDGF). Whereas Mydgf-deficient mice develop larger infarct scars and more severe contractile dysfunction compared to wild-type mice, treatment with recombinant Mydgf reduces scar size and contractile dysfunction after MI. This study is the first to assign a biological function to MYDGF, and it may serve as a prototypical example for the development of protein-based therapies for ischemic tissue repair.

Role of increased guanosine triphosphate cyclohydrolase-1 expression and tetrahydrobiopterin levels upon T cell activation.

Tetrahydrobiopterin (BH(4)) is an essential co-factor for the nitric-oxide (NO) synthases, and in its absence these enzymes produce superoxide (O(2)(·-)) rather than NO. The rate-limiting enzyme for BH(4) production is guanosine triphosphate cyclohydrolase-1 (GTPCH-1). Because endogenously produced NO affects T cell function, we sought to determine whether antigen stimulation affected T cell GTPCH-1 expression and ultimately BH(4) levels. Resting T cells had minimal expression of inducible NOS (NOS2), endothelial NOS (NOS3), and GTPCH-1 protein and nearly undetectable levels of BH(4). Anti-CD3 stimulation of T cells robustly stimulated the coordinated expression of NOS2, NOS3, and GTPCH-1 and markedly increased both GTPCH-1 activity and T cell BH(4) levels. The newly expressed GTPCH-1 was phosphorylated on serine 72 and pharmacological inhibition of casein kinase II reduced GTPCH-1 phosphorylation and blunted the increase in T cell BH(4). Inhibition of GTPCH-1 with diaminohydroxypyrimidine (1 mmol/liter) prevented T cell BH(4) accumulation, reduced NO production, and increased T cell O(2)(·-) production, due to both NOS2 and NOS3 uncoupling. GTPCH-1 inhibition also promoted TH(2) polarization in memory CD4 cells. Ovalbumin immunization of mice transgenic for an ovalbumin receptor (OT-II mice) confirmed a marked increase in T cell BH(4) in vivo. These studies identify a previously unidentified consequence of T cell activation, promoting BH(4) levels, NO production, and modulating T cell cytokine production.

Conditional transgenic expression of fibroblast growth factor 9 in the adult mouse heart reduces heart failure mortality after myocardial infarction.

BACKGROUND: Fibroblast growth factor 9 (FGF9) is secreted from bone marrow cells, which have been shown to improve systolic function after myocardial infarction (MI) in a clinical trial. FGF9 promotes cardiac vascularization during embryonic development but is only weakly expressed in the adult heart. METHODS AND RESULTS: We used a tetracycline-responsive binary transgene system based on the α-myosin heavy chain promoter to test whether conditional expression of FGF9 in the adult myocardium supports adaptation after MI. In sham-operated mice, transgenic FGF9 stimulated left ventricular hypertrophy with microvessel expansion and preserved systolic and diastolic function. After coronary artery ligation, transgenic FGF9 enhanced hypertrophy of the noninfarcted left ventricular myocardium with increased microvessel density, reduced interstitial fibrosis, attenuated fetal gene expression, and improved systolic function. Heart failure mortality after MI was markedly reduced by transgenic FGF9, whereas rupture rates were not affected. Adenoviral FGF9 gene transfer after MI similarly promoted left ventricular hypertrophy with improved systolic function and reduced heart failure mortality. Mechanistically, FGF9 stimulated proliferation and network formation of endothelial cells but induced no direct hypertrophic effects in neonatal or adult rat cardiomyocytes in vitro. FGF9-stimulated endothelial cell supernatants, however, induced cardiomyocyte hypertrophy via paracrine release of bone morphogenetic protein 6. In accord with this observation, expression of bone morphogenetic protein 6 and phosphorylation of its downstream targets SMAD1/5 were increased in the myocardium of FGF9 transgenic mice. CONCLUSIONS: Conditional expression of FGF9 promotes myocardial vascularization and hypertrophy with enhanced systolic function and reduced heart failure mortality after MI. These observations suggest a previously unrecognized therapeutic potential for FGF9 after MI.