Genes differentially expressed between pathogenic and non-pathogenic Entamoeba histolytica clones influence pathogenicity-associated phenotypes by multiple mechanisms.

Recently, two genes involved in amoebic liver abscess formation in a mouse model were identified by their differential expression of non-pathogenic (A1np) and pathogenic (B2p) clones of the Entamoeba histolytica isolate HM:1-IMSS. While overexpression of a gene encoding the metallopeptidase EhMP8-2 reduces the virulence of the pathogenic clone B2p, overexpression of the gene ehi_127670 (ehhp127), encoding a hypothetical protein, increases the virulence of the non-pathogenic clone A1np, while silencing this gene in the pathogenic B2p reduces virulence. To understand the role of both molecules in determining the pathogenicity of E. histolytica, silencing, and overexpression transfectants were characterized in detail. Silencing of ehmp8-2, of the homologous gene ehmp8-1, or both in non-pathogenic A1np trophozoites significantly altered the transcript levels of 347, 216, and 58 genes, respectively. This strong change in the expression profiles caused by the silencing of ehmp8-1 and ehmp8-2 implies that these peptidases regulate the expression of numerous genes. Consequently, numerous phenotypic characteristics, including cytopathic, hemolytic, and cysteine peptidase activity, were altered in response to their silencing. Silencing of ehhp127 in pathogenic B2p trophozoites did not affect the expression of other genes, whereas its overexpression in non-pathogenic A1np trophozoites results in an altered expression of approximately 140 genes. EhHP127 is important for trophozoite motility, as its silencing reduces, while its overexpression enhances movement activity. Interestingly, the specific silencing of ehhp127 also significantly affects cytopathic, cysteine peptidase, and hemolytic activities. All three molecules characterized in this study, namely EhMP8-1, EhMP8-2, and EhHP127, are present in amoeba vesicles. The results show that ehmp8-2 and ehhp127 are not only differentially expressed between pathogenic and non-pathogenic amoebae, but that they also significantly affect amoeba pathogenicity-associated phenotypes by completely different mechanisms. This observation suggests that the regulation of amoeba pathogenicity is achieved by a complex network of molecular mechanisms rather than by single factors.

[The Impact of Parenthood, Support, and Short-Term Contracts on Work-Family Conflict of Female and Male Residents' Career]. / Der Einfluss von Elternstatus, erlebter Unterstützung und Befristung auf das Belastungserleben und die Karriereentwicklung von Ärztinnen und Ärzten am Ende der Weiterbildung.

BACKGROUND: Work factors and work-family interference play an important role in physicians leaving clinical practice. OBJECTIVES: The purpose of this study was to examine residents' work-family conflict and family-work conflict in association with parental status, perceived support, and short-term contracts. MATERIAL AND METHODS: Data acquisition was carried out within the multi-centric and prospective "KarMed" study in Germany at the end of the postgraduate training in 2016 (N=433). The Work-Family Conflict and Family-Work Conflict scales were used. Further independent variables were gender, parental status, short-term contracts, and perceived support from partner. Results Female physicians with children interrupted postgraduate training five times more often then female physicians without children and 18 times more often than male physicians with children. Female as well as male physicians with children showed greater family-work conflicts, and female physicians without children scored higher on work-family conflict. Male physicians did not show significant results on work-family conflict. Neither short-term contracts nor perceived support from the partner had a significant influence on work-family or family work conflict. CONCLUSIONS: There is a need to reduce work-family conflicts and their associated factors in female resident physicians.

Diagnosis and management of postrefractive surgery ectasia.

Postrefractive surgery ectasia is a serious, sight-threatening complication seen after the following procedures: laser in situ keratomileusis, photorefractive keratectomy, small-incision lenticule extraction, radial keratotomy, and/or arcuate keratotomy. Specific risk factors may include age, corneal thickness, degree of refractive error, corneal topographic changes including irregular astigmatism, percent tissue ablation, and residual stromal bed. Biomarkers may be a new option to help indicate who is at greatest risk for ectasia. Visual aids including spectacles or contacts lenses are often required to achieve optimal vision. Collagen crosslinking is the only treatment believed to stop progression of ectasia and prevent keratoplasty. Other surgical options may include topography-guided phototherapeutic keratectomy and intrastromal corneal ring segments. Ultimately, an "ounce of prevention is a pound of cure," so careful preoperative screening and ultimately offering the safest and most effective treatments for patients is arguably the most important job of the refractive surgeon.

[Analysis of career and life satisfaction of women residents with children during their postgraduate training compared to male colleagues: A longitudinal analysis as part of the KarMed study]. / Berufsverlaufs- und Lebenszufriedenheit von Ärztinnen in fachärztlicher Weiterbildung mit Kindern im Vergleich zu ihren männlichen Kollegen ­ Eine longitudinale Untersuchung im Rahmen der KarMed-Studie.

OBJECTIVE: Former results of the KarMed study revealed a significant decrease in the career satisfaction of female physicians with children in the course of their postgraduate training compared to male physicians with children. Yet, female physicians with children showed the highest scores on satisfaction with life at the fourth year of postgraduate training. The present study evaluates whether the different courses of career satisfaction and life satisfaction of female physicians compared to male physicians are caused by parental status. METHODS: Data were collected in the course of the KarMed study (2008-2016). A cross-lagged panel design was used to analyze data from T2 to T5. RESULTS: The results indicate an inverse association of career satisfaction with life satisfaction. Women physicians with a low level of career satisfaction were more likely to have children than those with a higher career satisfaction. Furthermore, we found a causal effect of parental status on career satisfaction in male physicians. For female physicians, yet not for male physicians, life satisfaction predicts the parental status. CONCLUSIONS: The structural improvement in postgraduate training needs to be adjusted in terms of parental status. Prospective studies should take medical leave during pregnancy as well as parental leave of male medical residents into account.

An Alcohol Dehydrogenase 3 (ADH3) from Entamoeba histolytica Is Involved in the Detoxification of Toxic Aldehydes.

Recently, a putative alcohol dehydrogenase 3, termed EhADH3B of the Entamoeba histolytica isolate HM-1:IMSS was identified, which is expressed at higher levels in non-pathogenic than in pathogenic amoebae and whose overexpression reduces the virulence of pathogenic amoebae. In an in silico analysis performed in this study, we assigned EhADH3B to a four-member ADH3 family, with ehadh3b present as a duplicate (ehadh3ba/ehadh3bb). In long-term laboratory cultures a mutation was identified at position 496 of ehadh3ba, which codes for a stop codon, which was not the case for amoebae isolated from human stool samples. When using transfectants that overexpress or silence ehadh3bb, we found no or little effect on growth, size, erythrophagocytosis, motility, hemolytic or cysteine peptidase activity. Biochemical characterization of the recombinant EhADH3Bb revealed that this protein forms a dimer containing Ni2+ or Zn2+ as a co-factor and that the enzyme converts acetaldehyde and formaldehyde in the presence of NADPH. A catalytic activity based on alcohols as substrates was not detected. Based on the results, we postulate that EhADH3Bb can reduce free acetaldehyde released by hydrolysis from bifunctional acetaldehyde/alcohol dehydrogenase-bound thiohemiacetal and that it is involved in detoxification of toxic aldehydes produced by the host or the gut microbiota.

Burnout is associated with work-family conflict and gratification crisis among German resident physicians.

BACKGROUND: Studies investigating the longitudinal predictive value of burnout on both effort-reward imbalance (within the working place) and work-family conflict (between work and private life) in residents are lacking. Former cross-sectional studies showed an association of effort-reward imbalance and work family conflict with an elevated burnout risk in physicians. METHODS: Data acquisition was carried out within the multi-centric, longitudinal, and prospective "KarMed" study in Germany from 2009 until 2016. Yearly surveys including validated scales: the Maslach Burnout Inventory with its three subscales (emotional exhaustion, personal accomplishment, depersonalisation), the Work-Family Conflict Scale, and the Effort-Reward Imbalance Inventory. Further independent variables were gender and parental status.The analyses were based on general linear models and general linear mixed models with repeated measures designs. RESULTS: Significant time-fixed effects were found for all three subscales of the Maslach Burnout Inventory, with gender effects on the subscales emotional exhaustion and depersonalisation. The parental status had no significant effect on burnout. All estimated means for burnout during 6 years of post-graduate training were higher when work-family conflict and gratification crisis were taken into account. Personal accomplishment increased continuously over time as well showing neither gender differences nor influences by the parental status. CONCLUSIONS: Personal accomplishments might act as a buffer compensating to some extent for the physicians' stress experience. Given that burnout may be associated with poor patient care, there is a need to reduce burnout rates and their associated factors in resident physicians.

[Burnout and Gratification Crises in Female and Male Physicians during Postgraduate Medical Education in Germany - A Longitudinal Study]. / Burnout und Gratifikationskrisen im Längsschnitt bei Ärztinnen und Ärzten während der fachärztlichen Weiterbildung in Deutschland.

Several studies have demonstrated high work related stress and burnout symptoms in physicians. The study examined the longitudinal relationships of burnout and gratification crisis during 6 years of postgraduate medical education, controlled for gender and parental status. Data acquisition was carried out within the KarMed-study. Administered were the Maslach Burnout Inventory (MBI-HSS (MP)) (MBI) and the Effort-Reward-Imbalance (ERI). The analyses focused on general linear models and general linear mixed models with repeated measure designs. The amount of burnout perceived at the beginning of the postgraduate medical education is highly associated with the perceived amount of burnout at the end. Gratification crisis were significant for one subscale of the MBI (emotional exhaustion), yet not for personal accomplishment nor depersonalization. Significant time effects were found on all 3 subscales of the MBI, with gender effects on the subscales emotional exaustion and depersonalization. Having kids did not have significant effects, controlled for all measurement points of burnout as well as for gratification crisis. Theoretical implications and practical consequences for doctors, as well as the limitations of the study, are discussed.

[Longitudinal evaluation of female and male medical residents' career satisfaction]. / Longitudinale Untersuchung der Berufsverlaufszufriedenheit von Ärztinnen und Ärzten in der Facharztweiterbildung.

OBJECTIVE: Evaluation of longitudinal data of German medical residents' career satisfaction and its dependency on perceived delays in obtaining the degree as a medical specialist, as well as postgraduate training quality, controlled for gender, parental status, and specialty choice. METHODS: Data was collected within the KarMed study. The first data collection (T0) was conducted in 2008/2009 at the end of the practical year. Hierarchical linear models and path analysis were used to analyse longitudinal associations after three and five years (T3 to T5). RESULTS: A positive residents' career satisfaction had a small causal effect on the training quality. A delay in obtaining the degree as a medical specialist had a small negative effect on residents' career satisfaction. A high residents' career satisfaction was negatively associated with a delay in training. Gender predicted the career satisfaction of physicians with children. The career satisfaction of female physicians with children decreased significantly in the course of their postgraduate training compared to male physicians with children. The speciality choice had no significant impact on residents' career satisfaction. CONCLUSION: Residents who were satisfied with their job subjectively rated the quality of postgraduate training conditions more positively. The anticipated delays in obtaining the degree as a medical specialist and the residents' career satisfaction were reciprocally related. The improvement of career satisfaction in female physicians with children needs special attention in the future.

[What is Known About the Real Length of Postgraduate Medical Education in Germany?] / Was wissen wir über die reale Dauer der ärztlichen Weiterbildung in Deutschland?

OBJECTIVE: This study examines the real length of postgraduate medical education in Germany. The regulations define minimal time periods in months for each discipline. We especially analyze the differences between minimum and real length, as well as the percentages of interrupting or dropping out physicians by gender. METHODS: Within the KarMed study, annual postal surveys were sent to graduates of seven medical faculties in Germany from their last year of undergraduate education until after six years of postgraduate training. The return rate at baseline was 48 % (n = 1012) and the 5 surveys after baseline reached rates of 85 % and more. Descriptive statistics were used for analyses. RESULTS: Half of the residents did not finish within the minimum time period. This proportion was higher among women (65 %) then men (43 %); among women with child/children this proportion reached 91 %. Female residents expecting a prolongation estimated an average time period of 19.6 months (SD = 14.7), male residents of 11.5 months (SD = 8.6).Female residents named problems in relation to children as the most important factor. Half of the reasons given by male residents (and 31 % of those given by females) are related to organizational and curricular problems of postgraduate education. CONCLUSION: Effective measures are needed to reduce the problem of continuation of postgraduate education in the course of getting/having children and/or to promote the return to training in the hospital. For this, curricular and organizational measures, e. g. rotation plans and better possibilities for part-time training, should be offered.

Use of Topical Insulin to Treat Refractory Neurotrophic Corneal Ulcers.

PURPOSE: To report the clinical course of 6 patients with refractory neurotrophic corneal ulcers that were treated with topical insulin drops. METHODS: Retrospective chart review of patients who had neurotrophic corneal ulcers or epithelial defects refractory to standard medical and surgical treatment. Insulin drops, prepared by mixing regular insulin in artificial tears with a polyethylene glycol and propylene glycol base at a concentration of 1 unit per milliliter, were prescribed 2 to 3 times daily. RESULTS: Six patients, aged 2 to 73 years, developed neurotrophic corneal ulcers refractory to a range of medical and surgical treatments, including bandage contact lens, amniotic membrane grafting, and permanent tarsorrhaphy. Each patient was administered topical insulin drops with complete corneal reepithelialization within 7 to 25 days. CONCLUSIONS: Topical insulin may be a simple and effective treatment for refractory neurotrophic corneal ulcers. Further study is required to determine the clinical efficacy and side effect profile of insulin drops.

Safety and efficacy of autologous serum eye drop for treatment of dry eyes in graft-versus-host disease.

PURPOSE: To evaluate the treatment of autologous serum eye drops (ASED) on dry eyes in patients with graft-versus-host disease (GVHD). METHODS: A retrospective chart review of 35 patients with a history of ocular GVHD following hematopoietic stem cell transplantation that used ASED to alleviate dry eye symptoms was performed. Patients were categorized into three different groups. If patients had available ophthalmic data before and after starting treatment was group 1 (n = 14), had available ophthalmic data after starting treatment in group 2 (n = 10) and had available ophthalmic data before treatment or did not have any data after starting treatment in group 3 (n = 11). Data were collected on patient's age, gender, primary diagnosis, visual acuity and fluorescein corneal staining were collected on individual eyes in order to evaluate the efficacy of the ASED on alleviating dry eye-related signs and symptoms. RESULTS: No adverse ocular effect from the ASED was found in our series (except one fungal keratitis). All patients reported either improvement (55%) or stability (45%) in their ocular symptoms upon the use of ASED. In patients with available data before and after starting treatment, the corneal staining score improved by a median of 1 (p = 0.003) and the LogMAR visual acuity had a non-significant improvement. CONCLUSION: In our study, ASED used by patients with ocular GVHD were both safe and effective. ASED should be considered in patients with GVHD who suffer from dry eyes.

Patient satisfaction and clinical outcomes with laser refractive surgery performed by surgeons in training.

PURPOSE: To evaluate the refractive error quality of life (RQL) improvement, patient satisfaction, and clinical results of laser refractive surgery performed by residents or fellows. SETTING: Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, USA. DESIGN: Case series. METHODS: This study reviewed the clinical results of consecutive refractive surgery cases performed between March 2010 and February 2012 by ophthalmology residents or fellows. One-year postoperative analysis of the RQL and patient satisfaction in a subgroup of patients was completed using the National Eye Institute Refractive Error Correction Quality of Life-42 instrument (NEI RQL-42), and a comparison with NEI published normative data and post-refractive data was performed. RESULTS: Data were obtained from 138 eyes that had laser in situ keratomileusis and 4 eyes that had photorefractive keratectomy. The 1-year postoperative analysis of the RQL and patient satisfaction was completed in 34 patients. After 6 months postoperatively, the mean uncorrected distance visual acuity was 0.01 logMAR (95% confidence interval [CI], -0.012 to 0.023). The mean postoperative residual refractive error spherical equivalent was -0.20 diopter (D) (95% CI, -0.26 to -0.13). No eye lost corrected distance visual acuity. Equivalent or better satisfaction in the RQL was found in all but 1 of the 13 scale scores of the NEI RQL-42 compared with previously published NEI data. CONCLUSIONS: Laser refractive surgery performed by residents and fellows showed high patient satisfaction and an improved RQL 1-year postoperatively. Clinical outcomes validated the safety and efficacy of refractive surgery performed by surgeons in training. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.