Hepatitis C Virus Capsid Protein and Intracellular Lipids Interplay and its Association With Hepatic Steatosis

Background:

Hepatitis C Virus (HCV) is a major causative agent for chronic liver disease worldwide. Hepatic steatosis is a frequent histological feature in patients with chronic HCV. Both host and viral factors are involved in steatosis development. It results from uncontrolled growth of cytoplasmic lipid droplets (LDs) in hepatocytes. LDs are intracellular organelles playing key role in the HCV life cycle. HCV core protein localizes at the LD surface and this localization is crucial for virion production.

Objectives:

We explored in vitro interplay of core and LDs to investigate the role of core in steatosis.

Materials and Methods:

Core expression vectors were transfected in Huh-7 cells. The effect of core protein on LDs content and distribution in the cells was monitored by confocal microscopy. Cells were treated with oleic acid to analyze the effect of increased intracellular LDs on core expression. Core protein expression was monitored by western blot analysis.

Results:

Core expression altered the intracellular lipid metabolism, which resulted in a change in LDs morphology. Core LDs interaction was required for this effect since the mutation of two prolines (P138A, P143A), which impair LDs localization, had no impact on LDs morphology. Conversely, oleic acid induced intracellular LD content resulted in increased core expression.

Conclusions:

Core-LDs interaction may be an underlying molecular mechanism to induce liver steatosis in patients with HCV infection. This interaction is also crucial for efficient viral replication and persistence in infected cells. Steatosis can also interfere with efficient standard interferon therapy treatment. Management of steatosis should be considered along with standard care for achieving higher sustained virological response (SVR) in patients receiving interferon regimen.     

Human tooth germ stem cell response to calcium-silicate based endodontic cements

Objective

The aim of this study was to compare the cytotoxic effects of endodontic cements on human tooth germ stem cells (hTGSCs). MTA Fillapex, a mineral trioxide aggregate (MTA)-based, salicylate resin containing root canal sealer, was compared with iRoot SP, a bioceramic sealer, and AH Plus Jet, an epoxy resin-based root canal sealer.

Material and Methods

To evaluate cytotoxicity, all materials were packed into Teflon rings (4 mmµ3 mm) and co-cultured with hTGSCs with the aid of 24-well Transwell permeable supports, which had a pore size of 0.4 µm. Coverslips were coated with MTA Fillapex, iRoot SP and AH Plus Jet and each coverslip was placed onto the bottom of one well of a six-well plate for scanning electron microscopy (SEM) analysis. Before the cytotoxicity and SEM analysis, all samples were stored at 37ºC and at 95% humidity and 5% CO₂ for 24 hours to set. The cellular viability was analyzed using MTS test (3-(4,5-dimethyl-thiazol-2-yl)-5-(3-carboxy-methoxy-phenyl)-2-(4-sulfo-phenyl)-2H-tetrazolium). The cytotoxic effects and SEM visualization of the tested materials were analyzed at 24-hour, 72-hour, one-week and two-week periods.

Results

On the 1^st day, only MTA Fillapex caused cytotoxicity compared to negative control (NC) group (p<0.008). No significant difference was observed between the other tested materials at this period (p>0.05). After 14 days of incubation with the test materials, MTA Fillapex exhibited significantly higher cytotoxicity compared with iRoot SP, AH Plus Jet and the NC group (P<0.008). In the SEM analysis, the highest levels of cell attachment were observed for iRoot SP and the control group. After 24 hours, MTA Fillapex reduced the number of cells attached to the surface.

Conclusions

Within the limitations of this study, sealers exerted different cytotoxic effects on hTGSCs. Although all materials have exerted cellular toxicity, iRoot SP and AH Plus Jet may promote better attachment to hTGSCs.     

Delayed occurrence of spinal arachnoiditis following a caudal block

Abstract

Context

Spinal arachnoiditis is a rare disease caused by fibrosis and adhesion of the arachnoid membrane due to chronic inflammation. The causes of arachnoiditis are infection, spinal surgery, intraspinal injection of steroid or myelography dye, and spinal anesthesia.

Method

Case report.

Findings

A 60-year-old woman presented with progressive weakness and sensory change of both legs and urinary symptoms. She had received a single caudal block 6 months before symptom onset. Magnetic resonance imaging of the thoraco-lumbar spine showed an intradural extramedullary tumor at the T5–T7 level. She underwent laminectomy and tumor resection. The pathological finding was arachnoiditis. After surgery, a rehabilitation program of strengthening exercises of both lower extremities and gait training was started. At 2-month follow-up, she was able to walk with orthoses and performed daily activities with minimal assistance.

Conclusion

Symptoms of spinal arachnoiditis occurred 6 months after a single caudal block in this woman. Clinicians should be aware of this possible delayed complication.     

Insights from Expanded Adverse Childhood Experiences Screening in a Hospital-Based Outpatient Psychiatry Service

Adverse childhood experiences (ACEs) are associated with poor mental health in adulthood. Comprehensive prevalence data encompassing all 10 ACE questionnaire items has not previously been described in a hospital-based outpatient psychiatric clinic. This study assessed the prevalence of 10 ACEs in such a clinic and correlated ACEs with indicators of case severity. For 252 patients newly evaluated in an urban clinic, a retrospective chart review was completed and data was collected on ACE questionnaire responses, psychiatric, substance-related, and medical diagnoses, psychiatric hospitalizations, suicide attempts, and suicide and violence risk. Patients in the clinic had an average of 3.4 ACEs, higher than national community sample averages of 1.6. The percentages of patients with at least one, two, and four ACEs were 82% (n?=?207), 68% (n?=?172), and 42% (n?=?106) respectively (compared with 61%, 38%, and 15% nationally). ACEs had statistically significant correlations with an increased number of psychiatric diagnoses, substance use disorders, medical illnesses, suicide attempts, and suicide risk level. This study demonstrated that patients seeking psychiatric care from a hospital-based outpatient clinic are likely to be traumatized to a degree far exceeding what is typical in the general population. While a high prevalence of ACEs in a psychiatric population is an expected finding given the literature to date, this is the first study presenting data on the prevalence of ACEs in such a hospital-based community clinic. Additionally this study reinforces prior research correlating childhood adversity and case severity.

     

Hip surgery and its evidence base: progress over a decade?

Background

The burden of traumatic and elective hip surgery is set to grow. With an increasing number of techniques and implants against the background of an aging population, the emphasis on evidence-based treatment has never been greater. The purpose of this study was to assess changes in the levels of evidence in the hip literature over a decade.

Materials and methods

Articles pertaining to hip surgery from the years 2000 and 2010 in Hip International, Journal of Arthroplasty, Journal of Bone and Joint Surgery and The Bone and Joint Journal were analysed. Articles were ranked by a five-point level of evidence scale and by type of study, according to guidelines from the Centre for Evidence-based Medicine.

Results

531 articles were analysed from 48 countries. The kappa value for the inter-observer reliability showed excellent agreement between the reviewers for study type (κ = 0.956, P < 0.01) and for levels of evidence (κ = 0.772, P < 0.01). Between 2000 and 2010, the overall percentage of high-level evidence (levels I and II) studies more than doubled (12 to 31 %, P < 0.001). The most frequent study type was therapeutic; the USA and UK were the largest producers of published work in these journals, with contributions from other countries increasing markedly over the decade.

Conclusions

There has been a significant increase in high levels of evidence in hip surgery over a decade (P < 0.001). We recommend that all orthopaedic journals consider implementing compulsory declaration by authors of the level of evidence to help enhance quality of evidence.

Level of evidence

Level 2: economic and decision analysis.

     

The influence of MCAT and GPA preadmission academic metrics on interview scores

Medical school admissions interviews are used to assess applicants’ nonacademic characteristics as advocated by the Association of American Medical Colleges’ Advancing Holistic Review Initiative. The objective of this study is to determine whether academic metrics continue to significantly influence interviewers’ scores in holistic processes by blinding interviewers to applicants’ undergraduate grade point averages (uGPA) and Medical College Admission Test (MCAT). This study examines academic and demographic predictors of interview scores for two applicant cohorts at the University of Michigan Medical School. In 2012, interviewers were provided applicants’ uGPA and MCAT scores; in 2013, these academic metrics were withheld from interviewers’ files. Hierarchical regression analysis was conducted to examine the influence of academic and demographic variables on overall cohort interview scores. When interviewers were provided uGPA and MCAT scores, academic metrics explained more variation in interview scores (7.9%) than when interviewers were blinded to these metrics (4.1%). Further analysis showed a statistically significant interaction between cohort and uGPA, indicating that the association between uGPA and interview scores was significantly stronger for the 2012 unblinded cohort compared to the 2013 blinded cohort (β = .573, P < .05). By contrast, MCAT scores had no interactive effects on interviewer scores. While MCAT scores accounted for some variation in interview scores for both cohorts, only access to uGPA significantly influenced interviewers’ scores when looking at interaction effects. Withholding academic metrics from interviewers’ files may promote assessment of nonacademic characteristics independently from academic metrics.