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Globally, hepatitis B virus infection is one of the major causes of chronic liver diseases, apart from hepatitis C virus infection and alcohol abuse. The structure and genetic organization of HBV as well as the natural course and global burden of HBV infection are known in great detail. These advances have been successfully translated into important clinical applications, such as the sensitive and specific diagnosis, therapy and prevention of the hepatitis B virus-associated liver diseases, including liver cirrhosis and hepatocellular carcinoma. While it is possible to successfully prevent hepatitis B by vaccination, treatment of chronic HBV infection is more difficult than hepatitis C virus infection because it rarely eliminates the virus and makes an indefinite therapy necessary in most cases. Therefore, the World Health Organization goal of hepatitis B virus elimination by 2030 poses a major challenge to the medical community as well as to the health care authorities and requires their commitment to coordinated global interventions.

OBJECTIVE. The purpose of this study was to prospectively evaluate, using software support, the feasibility and the quantitative and qualitative image quality parameters of a tube voltage-tailored contrast medium (CM) application protocol for patient-specific injection during coronary CT angiography (CCTA). SUBJECTS AND METHODS. In the Voltage-Based Contrast Media Adaptation in Coronary Computed Tomography Angiography (VOLCANIC-CTA) study, a single-center trial, 120 patients referred for CCTA were prospectively assigned to a tube voltage-tailored CM injection protocol. Automated tube voltage levels were selected in 10-kV intervals and ranged from 70 to 130 kV, and the iodine delivery rate (IDR) was adapted to the tube voltage level using dedicated software. The administered CM volume (370 mg I/mL) ranged from 33 mL at 70 kV (IDR, 0.7 g I/s) to 65 mL at 130 kV (IDR, 1.7 g I/s). Attenuation was measured in the aorta and coronary arteries to calculate quantitative signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), and 5-point scales were used to evaluate overall image quality. Radiation metrics were also assessed and compared among the protocols. RESULTS. The mean age of the study patients was 62.5 ± 11.9 (SD) years. Image quality was rated as diagnostic in all patients. Contrast attenuation peaked at 70 kV (p < 0.001), whereas SNR and CNR parameters showed no significant differences between tube voltage levels (p ≥ 0.085). Additionally, no significant differences in subjective image quality parameters were found among the different protocols (p ≥ 0.139). The lowest radiation dose values were observed in the group assigned to the 70-kV protocol, which had a median radiation effective dose of 2.0 mSv (p < 0.001). CONCLUSION. The proposed tube voltage-tailored injection protocol allows individualized scanning of patients undergoing CCTA and significantly reduces CM and radiation dose while maintaining a high diagnostic image quality.

Hyperhidrosis, the medical term for excessive sweating beyond physiological need, is a condition with serious emotional and social consequences for affected patients. Symptoms usually appear in focal areas such as the feet, hands, axillae and face. Non-surgical treatment options such as topical antiperspirants or systemic medications are usually offered as a first step of treatment, although these therapies are often ineffective, especially in severe and intolerable cases of hyperhidrosis. In the treatment algorithm for patients suffering from hyperhidrosis, surgical thoracoscopic sympathicotomy offers a permanent solution, which is particularly effective in the treatment of palmar hyperhidrosis and facial blushing. In this review, we describe the current status of thoracoscopic sympathicotomy for palmar hyperhidrosis and facial blushing. In addition, we share the specific treatment approach, technique and results of our Hyperhidrosis Expert Center. Last, we share recommendations to ensure an effective, reproducible and safe application of single-port thoracoscopic sympathicotomy for palmar hyperhidrosis and facial blushing, based on our extensive experience.

With the recognition that carbonate reservoir rocks commonly contain a significant microporosity component (pore sizes ∼1 μm), there has been an ongoing effort to understand how this affects hydrocarbon recovery. This work reports x-ray microtomography (XMT) and nuclear magnetic resonance (NMR) data on two characteristic rock types. One is micropore dominated, and the other exhibits mixed-pore sizes. Several new techniques are introduced to accommodate investigation of full-sized core-plug samples having preserved wettability and to perform such studies with native fluids. First, the uses of high-field NMR techniques are demonstrated to determine porosity, overall oil and water content, and how these fluids are distributed between micro- and macropores. It is found that microporosity values agree with those obtained by optical (total pore system) analysis. Second, the use of xenon gas to tag the native oil phase for XMT imaging is demonstrated, showing how this helps determine contributions from pores that are smaller than the instrument resolution. Finally, a new method that uses NMR measurements of oil and water saturations to constrain the image analysis is demonstrated. The analysis shows the extent to which oil recovery occurs from the different pore systems. In both rock types, oil in the macroporosity is preferentially swept. Nevertheless, in agreement with a recent theory, oil recovery from the microporosity is significant. For the 70% microporosity sample, approximately one-third of the total oil recovery comes from the micropores, a factor that agrees well with theory.

In general, modeling oil-recovery is a challenging problem involving detailed fluid flow calculations with required structural details that challenge current experimental resolution. Recent laboratory experiments on mixed micro- and macro-pore suggest that there is a systematic relationship between remaining oil saturation (ROS) and the fraction of micro-pores. Working with experimental measurements of the pores obtained from X-ray tomography and mercury intrusion capillary pressure porosimetry, we define a digital rock model exemplifying the key structural elements of these carbonate grainstones. We then test two fluid-flow models: invasion percolation model and effective medium model. Although invasion percolation identifies the important impact of macro-pore percolation on permeability, it does not describe the dependence of ROS on micro-pore percentage. We thus modified the effective medium model by introducing a single-parameter descriptor, reff. Oil from pores r ≥ reff is fully removed, while for the remaining pores with r eff, their contribution is scaled by (r/reff)2. Applying this straightforward physics to pore size distributions for the mixed-pore grainstones reproduces the experimental ROS dependence.

To evaluate a new contrast media (CM) injection system in patients undergoing coronary computed tomography angiography (CCTA).Seventy-one consecutive patients (33 men and 38 women, mean age 59.0 ± 14.5 years) who underwent CCTA between February and April 2019 using the CT injection system MEDRAD Stellant FLEX (Bayer) were included retrospectively in this single-center study. Quantitative and qualitative image quality parameters were assessed, and the injection system's usability and operational efficiency were evaluated. Results were compared with a matched control group.All examinations were rated as diagnostic. Usability and operational efficiency of the new injector were rated higher than that of the standard injector system, and no significant differences were found for quantitative and qualitative image quality parameters compared with the control group (Software-based injection facilitates individualized CM application while maintaining high image quality standards in CCTA. Diagnostic accuracy analysis was not performed, but as image quality analysis showed no significant differences, no discrepancies regarding this issue are expected.This study demonstrates that the MEDRAD Stellant FLEX CT injection system allows for consistent high-quality CCTA scanning with increased usability and operational efficiency.

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. The major etiologies and risk factors for the development of HCC are well defined and some of the multiple steps involved in hepatocarcinogenesis have been elucidated in recent years. Despite these scientific advances and the implementation of measures for the early detection of HCC in patients at risk, patient survival has not significantly improved during the last three decades. This is due to the advanced stage of the disease at the time of clinical presentation and the limited therapeutic options. The therapeutic options fall into several categories: (i) surgical interventions including tumor resection and liver transplantation, (ii) percutaneous interventions including ethanol injection and radiofrequency thermal ablation, (iii) transarterial interventions including embolization, chemoembolization and selective internal radiotherapy, (iv) external radiation therapy and (v) systemic strategies with cytotoxic agents and molecularly targeted therapies as well as immunotherapies. These therapeutic strategies have been evaluated in part in randomized controlled clinical trials that are the basis for actual therapeutic recommendations. While surgery, percutaneous and transarterial interventions are effective in patients with limited disease (1-3 lesions

Enterococcus faecium (E. faecium) has emerged as one of today's leading causes of health care-associated infections that is difficult to treat with the available antibiotics. These pathogens produce capsular polysaccharides on the cell surface which play a significant role in adhesion, virulence and evasion. Therefore, we aimed at the identification and characterization of bacterial polysaccharide antigens which are central for the development of vaccine-based prophylactic approaches. The crude cell wall-associated polysaccharides from E. faecium, its mutant and complemented strains were purified and analyzed by a primary antibody raised against lipoteichoic acid (LTA) and diheteroglycan (DHG). The resistant E. faecium strains presumably possess novel capsular polysaccharides that allow them to avoid the evasion from opsonic killing. The E. faecium U0317 strain was very well opsonized by anti-U0317 (~95%), an antibody against the whole bacterial cell. The deletion mutant showed a significantly increased susceptibility to opsonophagocytic killing (90-95%) against the penicillin binding protein (anti-PBP-5). By comparison, in a mouse urinary tract and rat endocarditis infection model, respectively, there were no significant differences in virulence. In this study we explored the biological role of the capsule of E. faecium. Our findings showed that the U0317 strain is not only sensitive to anti-LTA but also to antibodies against other enterococcal surface proteins. Our findings demonstrate that polysaccharides capsule mediated-resistance to opsonophagocytosis. We also found that the capsular polysaccharides do not play an important role in bacterial virulence in urinary tract and infective endocarditis in vivo models.

Carbonate reservoirs are often comprised of a heterogeneous pore system within a matrix of variably distributed minerals including anhydrite, dolomite, and calcite. When describing carbonate thin sections, it is routine to assign relative abundance levels to each of these components, which are qualitative to semi-quantitative (e.g. point-counting) and vary greatly depending on the petrographer. Over the past few decades, image analysis has gained wide use among petrographers, however, thin section characterization using this technique has been primarily limited to the pore space due to the difficulty associated with optical recognition beyond the blue-dyed epoxy associated with the pores. Here, we present a new method of computerized object-based image segmentation (Quantitative Digital Petrography: QDP) that relies on a predefined rule set to enable rapid, automated thin section quantification with only minor human interaction. We have developed a novel work flow that automatically isolates the sample on a high-resolution (i.e.

Until recently, human microbiology was based on the identification of single microbes, such as bacteria, fungi and viruses, frequently isolated from patients with acute or chronic infections. Novel culture-independent molecular biochemical analyses (genomics, transcriptomics, proteomics, metabolomics) allow today to detect and classify the diverse microorganisms in a given ecosystem (microbiota), such as the gastrointestinal tract, the skin, the airway system, the urogenital tract and others, and to assess all genomes in these ecosystems (microbiome) as well as their gene products. These analyses revealed that each individual has its own microbiota that plays a role in health and disease. In addition, they greatly contributed to the recent advances in the understanding of the pathogenesis of a wide range of human diseases. It is to be expected that these new insights will translate into diagnostic, therapeutic and preventive measures in the context of personalized/ precision medicine.

Background and aim Non-invasive markers are essential to assess the progression of chronic liver diseases to fibrosis/ cirrhosis and the effectiveness of therapeutic strategies. The aim of this study was to evaluate the ability of non-invasive markers to identify significant fibrosis, severe fibrosis, and cirrhosis in patients with autoimmune hepatitis (AIH). Methods Seventy-six patients with AIH were enrolled in the study and analyzed for the following parameters of liver fibrosis: Fibrosis 4 score (FIB-4), aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio (AAR), AST to platelet count ratio (APRI), and platelet count to spleen diameter (PC/SD) ratio. All patients underwent liver biopsy. The diagnostic accuracy of tests was evaluated by the area under the receiver operating characteristic curve (AUROC). Results Among the 76 AIH patients, 55 (72.3%) had significant fibrosis (≥ F2), 37 (48.7%) had severe fibrosis (≥ F3), and 29 (38.2%) had cirrhosis (F4). PC/SD ratio (AUROC = 0.840) was superior to AAR (AUROC = 0.756), FIB-4 (AUROC = 0.702), and APRI (AUROC = 0.626) in discriminating between mild and significant fibrosis (≥ F2). The AUROCs of PC/SD ratio, FIB-4, AAR, and APRI were 0.884, 0.742, 0.731, and 0.707, respectively, for severe fibrosis (≥ F3); 0.968, 0.795, 0.744, and 0.723, respectively, for cirrhosis (F4). PC/SD ratio correctly identified 85.1% of patients with severe fibrosis, and 89.6% of patients with cirrhosis. Conclusions PC/SD ratio proved to be a simple non-invasive tool to correctly identify AIH patients with severe fibrosis and cirrhosis, thereby reducing the need for a liver biopsy in these patients.

We report the first direct measurements of methane density in shale gas using small-angle neutron scattering. At a constant pressure, the density of methane in the inorganic pores is similar to the gas bulk density of the system conditions. In contrast, the methane density is 2.1 ± 0.2 times greater in the organic mesopores. Classical density functional theory calculations show that this excess density in the organic pores persists to elevated temperatures, typical of shale gas reservoir conditions, providing new insight into the hydrocarbon storage mechanisms within these reservoirs.

The pore size distribution and architecture in gas shales were studied using a combination of small-angle neutron scattering (SANS), mercury injection capillary pressure (MICP), and helium ion microscopy (HIM). SANS analysis shows that the pore size population is not a power-law distribution across many length scales, typical of sedimentary rocks, but contains an anomalous population of pores on-the-order ∼2 nm, housed primarily in the organic matter. A model is presented showing how a “foamy porosity” with such a characteristic size is a direct result of diagenetic evolution of kerogen. Cross-linking of the kerogen combined with phase separation of gas/oil, leads to arrested coarsening with a length scale set by the cross-length density. These pore populations determined by the scattering model are directly supported by HIM images. Pore connectivity determined through pore-size-to-pore-throat analysis, suggests that interpore connections are also distinct from typical sedimentary rocks. The pore/throat r...

Until recently, human microbiology was based on the identification of single microbes, such as bacteria, fungi and viruses, frequently isolated from patients with acute or chronic infections. Novel culture-independent molecular biochemical analyses (genomics, transcriptomics, proteomics, metabolomics) allow today to detect and classify the diverse microorganisms in a given ecosystem (microbiota), such as the gastrointestinal tract, the skin, the airway system, the urogenital tract and others, and to assess all genomes in these ecosystems (microbiome) as well as their gene products. These analyses revealed that each individual has its own microbiota that plays a role in health and disease. In addition, they greatly contributed to the recent advances in the understanding of the pathogenesis of a wide range of human diseases. It is to be expected that these new insights will translate into diagnostic, therapeutic and preventive measures in the context of personalized/precision medicine.