The ability of Hepascore to predict liver fibrosis in chronic liver disease: A meta-analysis

Background & Aims: Hepascore is a serum model that was developed to assess the severity of liver fibrosis. It has been well validated in common causes of chronic liver disease. This study performed a meta-analysis to evaluate the pooled diagnostic performance of Hepascore and to compare it for different aetiologies of chronic liver disease. Methods: Two reviewers searched electronic databases from October 2005 to September 2015 for studies that evaluated the diagnostic performance of Hepascore for liver fibrosis in chronic liver disease. Results: 21 studies were included. The AUROC was adjusted according to the distribution of fibrosis stages. The mean adjusted AUROC was 0.83 (95%CI, 0.81-0.85) for significant fibrosis, 0.89 (95%CI, 0.85-0.92) for advance fibrosis and 0.93 (95%CI, 0.91-0.95) for cirrhosis. A cut point of 0.50-0.55 achieved a summary sensitivity of 70% and a summary specificity of 79% to predict significant fibrosis. A cut point of 0.50-0.61 had a summary sensitivity of 81% and a summary specificity of 74% to predict advanced fibrosis. A cut point of 0.80-0.84 had a summary sensitivity of 72% and a summary specificity of 0.88% to predict cirrhosis. The accuracy of Hepascore was similar among all disease aetiologies for the prediction of cirrhosis. However, Hepascore had better diagnostic ability for significant and advanced fibrosis in chronic hepatitis C, chronic hepatitis B and alcoholic liver disease than for non-alcoholic fatty liver disease and HIV co-infected viral hepatitis. Conclusions: Hepascore is a clinically useful measure of liver fibrosis in patients with common causes of chronic liver disease

A role for NRAGE in NF-κB activation through the non-canonical BMP pathway

<p>Abstract</p> <p>Background</p> <p>Previous studies have linked neurotrophin receptor-interacting MAGE protein to the bone morphogenic protein signaling pathway and its effect on p38 mediated apoptosis of neural progenitor cells via the XIAP-Tak1-Tab1 complex. Its effect on NF-κB has yet to be explored.</p> <p>Results</p> <p>Herein we report that NRAGE, via the same XIAP-Tak1-Tab1 complex, is required for the phosphorylation of IKK -α/β and subsequent transcriptional activation of the p65 subunit of NF-κB. Ablation of endogenous NRAGE by siRNA inhibited NF-κB pathway activation, while ablation of Tak1 and Tab1 by morpholino inhibited overexpression of NRAGE from activating NF-κB. Finally, cytokine profiling of an NRAGE over-expressing stable line revealed the expression of macrophage migration inhibitory factor.</p> <p>Conclusion</p> <p>Modulation of NRAGE expression revealed novel roles in regulating NF-κB activity in the non-canonical bone morphogenic protein signaling pathway. The expression of macrophage migration inhibitory factor by bone morphogenic protein -4 reveals novel crosstalk between an immune cytokine and a developmental pathway.</p

Phosphoryl Transfer Step in the C-terminal Src Kinase Controls Src Recognition

All members of the Src family of nonreceptor protein tyrosine kinases are phosphorylated and subsequently down-regulated by the C-terminal Src kinase, Csk. Although the recognition of Src protein substrates is essential for a diverse set of signaling events linked to cellular growth and differentiation, the factors controlling this critical protein-protein interaction are not well known. To understand how Csk recognizes Src, the chemical/physical events that modulate apparent substrate affinity and turnover were investigated. Src is phosphorylated in a biphasic manner in rapid quench flow experiments, suggesting that the phosphoryl transfer step is fast and highly favorable and does not limit overall turnover. As opposed to other kinase-substrate pairs, turnover is not limited by the physical release of ADP based on stopped-flow fluorescence and catalytic trapping experiments, suggesting that other steps control net phosphorylation. The Kd for Src is considerably larger than the Km based on single turnover kinetic and equilibrium sedimentation experiments. Taken together, the data are consistent with a mechanism whereby Csk achieves a low Km for the substrate Src, not by stabilizing protein-protein interactions but rather by facilitating a fast phosphoryl transfer step. In this manner, the phosphoryl transfer step functions as a chemical clamp facilitating substrate recognition

Mouse cytomegalovirus-experienced ILC1s acquire a memory response dependent on the viral glycoprotein m12.

Innate lymphoid cells (ILCs) are tissue-resident sentinels that are essential for early host protection from pathogens at initial sites of infection. However, whether pathogen-derived antigens directly modulate the responses of tissue-resident ILCs has remained unclear. In the present study, it was found that liver-resident type 1 ILCs (ILC1s) expanded locally and persisted after the resolution of infection with mouse cytomegalovirus (MCMV). ILC1s acquired stable transcriptional, epigenetic and phenotypic changes a month after the resolution of MCMV infection, and showed an enhanced protective effector response to secondary challenge with MCMV consistent with a memory lymphocyte response. Memory ILC1 responses were dependent on the MCMV-encoded glycoprotein m12, and were independent of bystander activation by proinflammatory cytokines after heterologous infection. Thus, liver ILC1s acquire adaptive features in an MCMV-specific manner

Intra-Domain Cross-Talk Regulates Serine-Arginine Protein Kinase 1-Dependent Phosphorylation and Splicing Function of Transformer 2β1

Transformer 2β1 (Tra2β1) is a splicing effector protein composed of a core RNA recognition motif flanked by two arginine-serine-rich (RS) domains, RS1 and RS2. Although Tra2β1-dependent splicing is regulated by phosphorylation, very little is known about how protein kinases phosphorylate these two RS domains. We now show that the serine-arginine protein kinase-1 (SRPK1) is a regulator of Tra2β1 and promotes exon inclusion in the survival motor neuron gene 2 (SMN2). To understand how SRPK1 phosphorylates this splicing factor, we performed mass spectrometric and kinetic experiments. We found that SRPK1 specifically phosphorylates 21 serines in RS1, a process facilitated by a docking groove in the kinase domain. Although SRPK1 readily phosphorylates RS2 in a splice variant lacking the N-terminal RS domain (Tra2β3), RS1 blocks phosphorylation of these serines in the full-length Tra2β1. Thus, RS2 serves two new functions. First, RS2 positively regulates binding of the central RNA recognition motif to an exonic splicing enhancer sequence, a phenomenon reversed by SRPK1 phosphorylation on RS1. Second, RS2 enhances ligand exchange in the SRPK1 active site allowing highly efficient Tra2β1 phosphorylation. These studies demonstrate that SRPK1 is a regulator of Tra2β1 splicing function and that the individual RS domains engage in considerable cross-talk, assuming novel functions with regard to RNA binding, splicing, and SRPK1 catalysis

Pre- and post- prandial appetite hormone levels in normal weight and severely obese women

<p>Abstract</p> <p>Background</p> <p>Appetite is affected by many factors including the hormones leptin, ghrelin and adiponectin. Ghrelin stimulates hunger, leptin promotes satiety, and adiponectin affects insulin response. This study was designed to test whether the pre- and postprandial response of key appetite hormones differs in normal weight (NW) and severely obese (SO) women.</p> <p>Methods</p> <p>Twenty three women ages 25–50 were recruited for this study including 10 NW (BMI = 23.1 ± 1.3 kg/m²) and 13 SO (BMI = 44.5 ± 7.1 kg/m²). The study was conducted in a hospital-based clinical research centre. Following a 12-hour fast, participants had a baseline blood draw, consumed a moderately high carbohydrate meal (60% carbohydrate, 20% protein, 20% fat) based on body weight. Postprandially, participants had six blood samples drawn at 0, 15, 30, 60, 90, and 120 minutes. Primary measures included pre- and post-prandial total ghrelin, leptin, adiponectin and insulin. A repeated measures general linear model was used to evaluate the hormone changes by group and time (significance p ≤ 0.05).</p> <p>Results</p> <p>There were significant differences between the NW and the SO for all hormones in the preprandial fasting state. The postprandial responses between the SO versus NW revealed: higher leptin (p < 0.0001), lower adiponectin (p = 0.04), trend for lower ghrelin (p = 0.06) and insulin was not different (p = 0.26). Postprandial responses over time between the SO versus NW: higher leptin (p < 0.001), lower ghrelin and adiponectin (p = 0.004, p = 0.015, respectively), and trend for higher insulin (p = 0.06).</p> <p>Conclusion</p> <p>This study indicates that significant differences in both pre- and selected post- prandial levels of leptin, ghrelin, adiponectin and insulin exist between NW and SO women. Improving our understanding of the biochemical mechanisms accounting for these differences in appetite hormones among individuals with varying body size and adiposity should aid in the development of future therapies to prevent and treat obesity.</p

The Feasibility of the Use of Video Capture, Feedback Process in the Obstetrics and Gynecology Residents

The Feasibility of the use of Video Capture, Feedback Process in the Obstetrics and Gynecology Residents Sean Adams Martin A. Martino, MD; Joseph E. Patruno, MD; Timothy M. Pellini, MD Abstract Educating a resident and proving that he is capable of consistently performing a procedure is a difficult task. This is vastly important for the patients safety. One of the key parts of becoming a quality surgeon is technical skill. To assess the technical skills of the obstetrics and gynecology residents, myself and four other students performed a video capture, feedback process using a product called SimCapture. This process involved us video recording four different types of surgeries performed by residents. After each case, the resident and attending participated in a feedback process to review the strengths and weaknesses of the resident for that particular case. The feasibility of the process is very significant in helping determine if this method is effective and if it should be used in the future. Often times, we planned on recording a case for our data in which something went wrong such as a resident who didn’t operate at all or a change in the operating room (OR) schedule we were not made aware of. This caused us to miss quite a few cases that we planned on recording. Nurses, attendings, and residents were slightly skeptical about our study initially, but over time they became more comfortable with us recording the surgeries. The consistent issues and obstacles forced us to be very proactive and flexible. Ultimately, we were successful in collecting the research we wanted. Background Becoming an expert surgeon is a long and difficult process including many years of medical school and residency. This calls for thousands of hours of learning information, practicing on simulators, and performing surgeries with an attending surgeon. It is important that the attending surgeon mentors and assists the resident(1). The education of these residents must be maximized for the purpose of patient safety. While there are many factors in determining a surgeons abilities, technical skill is the most related to the outcome of the patient (2). Evaluating the technical skill of residents is an especially challenging subject. An educational program called FLS (The Fundamentals of Laproscopic Surgery) was developed to improve the knowledge and technical skills of residents (3). A study done by three Washington D.C hospitals compared the FLS examination scores of residents to their objective OR skill evaluations (3). The results showed a clear relationship as residents with higher FLS scores also received better evaluations in the OR (3). The FLS test includes a written section to express knowledge of laproscopic surgery as well as skills tests on box trainers (3). Another way to evaluate the technical skill of surgeons is through video analysis. A study done by the Michigan Bariatric Surgery Collaborative (MBSC) had 20 surgeons submit a video of themselves performing a laproscopic gastric bypass (2). The skills of these surgeons were then evaluated by blinded surgeons and rated on a 1 to 5 scale. These scores were then compared to the outcomes of surgeries done by the same 20 surgeons on around 10,000 patients (2). The results showed that the top quartile of scores were related to lower complication rates (2). The bottom quartile were related to higher complication rates (2). The use of videotape assessment is a very effective way for residency programs to improve the technical skill of residents through feedback. It is also a way to determine whether or not their residents are competent performing certain surgical procedures. If hospitals are considering a form of video taping and feedback process, it is important that they know the feasibility of the process. How accepting were the residents and attending surgeons to the process? Were participating in the debriefing after? Was the process overcrowding the OR? Was it difficult to record the cases? A type of video recording technology called SimCapture was purchased by the Lehigh Valley Hospital for the purpose of recording residents. The technology includes a software programmed into a laptop computer that then allows you to record surgeries from a webcam. The data recorded on the webcam and through connection to the endoscopic tower is then stored on the software for further analysis. Purpose The purpose of my project is to determine the feasibility of a video capture, feedback process that will be used to improve and calculate the technical skill of obstetrics and gynecology residents at the Lehigh Valley Hospital. The video capture, feedback process involves recording the surgeries performed by a number of different residents. The attending surgeons will provide feedback based on their real time analysis of the residents performance. The videotapes of each case will be sent out to blinded experts for analysis using the same evaluation forms that were completed by the attending surgeon and resident that were present at the case. In the future, the recorded surgeries could also be used to build a portfolio for each resident to show their competency performing certain procedures. My complete focus will be on determining the degree of how convenient a video capture, feedback process can be done. Methods For our data collection, we recorded the obstetrics and gynecology residents performing four different types of surgeries. These different surgeries included C section, Hysteroscopy, Robotic Hysterectomy, and Laparoscopic tubal ligation (BTL). Our exact methods for recording the surgeries varied slightly depending on the case. The residents varied in experience from first through fourth year. The fourth year residents would often do large portions of the cases while the less experienced residents did less. The night before the cases, we would look at the OR schedule and plan out the cases we were going to record the next day. A group of two scholars would show up about a half hour before the first surgery. At this time they would find the resident and attending for the case to introduce themselves, tell them about the project, and ask them to participate in a debrief session following the case. The scholars would then enter into the OR to set up the technology. The computer with the Sim Capture program is connected to the endoscopic tower using the appropriate adaptors. This allows us to get an internal view of the patient. A camera attached to an extension chord is mounted on top of an IV pole using a clamp and then angled toward the incision made on the patient. For C sections, there is no endoscopic tower used. For robotic hysterectomy cases, we record the resident’s hands when using the robot instead of the incisions. One scholar then logs into the SimCapture program and runs a new session. To run the session, they have to input information such as the resident number, name of scholar operating the system, and the type of surgery. Once everything is set up, both scholars leave the OR until the patient is all ready to be operated on. Upon re-entering the OR, the scholar working the laptop then starts recording once time out is called. Every time the resident stops or starts operating, an annotation is made in the video tape. The scholar who is not working the SimCapture program fills out the form which keeps track of each time the attending teaches the resident. That scholar also completes the feasibility form which notes if the resident, attending, and other staff were understanding of our study as well as any problems that occurred. Once the surgery is completed, recording is stopped and both scholars disassemble the equipment. After leaving the OR; both scholars, the resident, and the attending participate in a short debriefing session. In this debriefing session, the attending and resident each complete the appropriate OPRS and milestone forms. The resident then discusses what he thought he did well and also what could be improved. The attending follows up with his feedback. Once the debriefing is completed, the scholars then plug all the forms into the SimCapture program and discuss the case. Results Figure 1: Number of cases recorded for each procedure Procedure Number of cases recorded Hysteroscopy 11 Robotic Hysterectomy 8 C section 17 BTL 3 Total 39 Figure 2: Percentage of cases recorded Percentage of Cases Recorded Recorded Missed Total Percent Recorded 39 25 64 61% Figure 4: Summary of feasibility form Average time to set up equipment 5.7 min Average time to disassemble equipment 3.2 min Average time to debrief 3.6 min Percent of cases where debrief occurred 61% Percent of cases where resident was receptive to process 97% Percent of cases where attending was receptive to process 95% Percent of cases where OR staff was receptive to process 97% Conclusion / discussion After about six weeks of collecting data, we were able to record 39 cases as shown in figure 1. You can see in figure 2 that we did miss quite a few of the cases that we had planned on recording. Our 61% success rate had to do with the number of issues and obstacles that occurred throughout the process. Some of the obstacles included technology issues, resident not operating, changes in the OR schedule, surgeon preference, and patient preference. Figure 3 allows you to see the breakdown of how often certain issues occurred in the 25 cases we missed. As we became more comfortable with our video capture feedback process, the issues became less and less frequent. Some of the initial technology issues included delays in the camera feed, one camera not working at all, SimCaptu re not picking up the camera and tower feeds, and not having the correct adaptor to connect the program into the tower. We sorted out almost all of these issues in the first few weeks. Experience also allowed us to perform the process more efficiently, including setting up the equipment. Over time, we had developed a consistent system to record cases and stay out of the way of the staff. This allowed our process to gain acceptance by attendings, residents, and OR staff. After performing a number of cases, they became more comfortable with us recording the cases in the OR. Figure 4 shows a summary of the results for the feasibility forms we completed for each case. One of the other key difficulties of our process was getting the resident and attendings to participate in the debriefing after the case. This is shown by the fact that only 61% of the cases had debriefings. The attendings, residents, or both of them were often needed elsewhere and had little time after the cases.Throughout the 6 weeks, we were forced to make quite and few innovations and be flexible with our process. For example, we needed to purchase an adaptor that would allow us to connect the SimCapture program into the endoscopic tower. Often times, the nurses and OR staff got very nervous about all the wires that we were bringing into the OR. We often had to be innovative by attaching the camera to the IV pole to get a good angle and laying a mat over all the wires. Even with all these issues, we were able to record a very good amount of cases over the 6 week period. This shows that a video capture, feedback process using a system such as SimCapture can be very effective in evaluating the technical skills of residents. References Levy, B. (2012). Experience Counts. American College of Obstetricians and Gynecologists, 119(4), 693-694. Birkmeyer, J. (2013, October 10). Surgical Skill and Complication Rates after Bariatric Surgery. www.nejm.org. 3. Antosh, D. (2012, December 8). Blinded Assessment of Operative Performance After Fundamentals of Laparoscopic Surgery in Gynecology Training. www.jmig.org

Substrate-Specific Reorganization of the Conformational Ensemble of CSK Implicates Novel Modes of Kinase Function

Protein kinases use ATP as a phosphoryl donor for the posttranslational modification of signaling targets. It is generally thought that the binding of this nucleotide induces conformational changes leading to closed, more compact forms of the kinase domain that ideally orient active-site residues for efficient catalysis. The kinase domain is oftentimes flanked by additional ligand binding domains that up- or down-regulate catalytic function. C-terminal Src kinase (Csk) is a multidomain tyrosine kinase that is up-regulated by N-terminal SH2 and SH3 domains. Although the X-ray structure of Csk suggests the enzyme is compact, X-ray scattering studies indicate that the enzyme possesses both compact and open conformational forms in solution. Here, we investigated whether interactions with the ATP analog AMP-PNP and ADP can shift the conformational ensemble of Csk in solution using a combination of small angle x-ray scattering and molecular dynamics simulations. We find that binding of AMP-PNP shifts the ensemble towards more extended rather than more compact conformations. Binding of ADP further shifts the ensemble towards extended conformations, including highly extended conformations not adopted by the apo protein, nor by the AMP-PNP bound protein. These ensembles indicate that any compaction of the kinase domain induced by nucleotide binding does not extend to the overall multi-domain architecture. Instead, assembly of an ATP-bound kinase domain generates further extended forms of Csk that may have relevance for kinase scaffolding and Src regulation in the cell

Dynamics of genotype-specific HPV clearance and reinfection in rural Ghana may compromise HPV screening approaches

Persistent Human Papillomavirus (HPV) infection is a prerequisite for cervical cancer development. Few studies investigated clearance of high-risk HPV in low-and-middle-income countries. Our study investigated HPV clearance and persistence over four years in women from North Tongu District, Ghana. In 2010/2011, cervical swabs of 500 patients were collected and HPV genotyped (nested multiplex PCR) in Accra, Ghana. In 2014, 104 women who previously tested positive for high-risk HPV and remained untreated were re-tested for HPV. Cytobrush samples were genotyped (GP5+/6+ PCR & Luminex-MPG readout) in Berlin, Germany. Positively tested patients underwent colposcopy and treatment if indicated. Of 104 women, who tested high-risk HPV+ in 2010/2011, seven (6,7%; 95%CI: 2.7-13.4%) had ≥1 persistent high-risk-infection after ~4 years (mean age 39 years). Ninety-seven (93,3%; 95%CI: 86.6-97.3%) had cleared the original infection, while 22 (21.2%; 95%CI: 13.8-30.3%) had acquired new high-risk infections with other genotypes. Persistent types found were HPV 16, 18, 35, 39, 51, 52, 58, and 68. Among those patients, one case of CIN2 (HPV 68) and one micro-invasive cervical cancer (HPV 16) were detected. This longitudinal observational data suggest that single HPV screening rounds may lead to over-referral. Including type-specific HPV re-testing or additional triage methods could help reduce follow-up rates