The Outcome of Laparoscopic Versus Open Appendectomy in Childhood.

BACKGROUND: Appendectomy in children is performed either lapa - roscopically (LA) or by open surgery (OA). We studied whether, and how, the outcome is affected by the technique used and by the intraoperative conversion of LA to OA. METHODS: We analyzed routine data from children and adolescents in three age groups (1-5 years, 6-12 years, and 13-17 years) who were insured by the AOK statutory health insurance carrier in Germany and who underwent appendectomy in the period 2017-2019. General surgical complications and reoperations within 90 days were assessed with relevant indicators. Associations between the surgical technique and these indicators were studied with logistic regression. RESULTS: Of the 21 541 patients included in the study, general surgical complications were observed in 2.1% and reoperations in 1.8% overall. Broken down by age group, the corresponding figures were 5.4% and 4.4% (age 1 to 5), 2.5% and 1.8% (age 6 to 12), and 1.5% and 1.6% (age 13 to 17). The main risk factors for complications and reoperations were acute complicated appendicitis and conversion from LA to OA. Regression analysis revealed similar outcomes with OA compared to LA in the 1-to-5 age group, (odds ratios and 95% confidence intervals: 1.1 [0.6; 2.1] for general surgical complications and 1.5 [0.8; 2.7] for reoperations), but worse outcomes with OA in the other two age groups (age 6 to 12: 1.9 [1.2; 2.9] and 2.1 [1.5; 2.9]; age 13 to 17: 1.7 [1.0; 2.9] and 2.2 [1.4; 3.6]). When conversions were assigned to the LA group, the odds ratio (OA compared to LA) for reoperation across all age groups was 3.5 [2.8; 4.4] in patients with acute uncomplicated appendicitis and 4.2 [3.4; 5.3] in patients with complicated appendicitis. Complicated appendicitis also increased the rate of general surgical complications and the length of stay in hospital. CONCLUSION: Among children in the two older age groups, LA was followed by fewer general surgical complications and reoperations than OA. These differences were less pronounced when conversions were counted as belonging to the LA group. Children aged 1-5 appear to benefit the least from the lapa - roscopic technique.

Influence of COVID-19 confinement measures on appendectomies in Germany-a claims data analysis of 9797 patients.

PURPOSE: COVID-19 pandemic had multiple influences on the social, industrial, and medical situation in all affected countries. Measures of obligatory medical confinement were suspensions of scheduled non-emergent surgical procedures and outpatients' clinics as well as overall access restrictions to hospitals and medical practices. The aim of this retrospective study was to assess if the obligatory confinement (lockdown) had an effect on the number of appendectomies (during and after the period of lockdown). METHODS: This retrospective study was based on anonymized nationwide administrative claims data of the German Local General Sickness Fund (AOK). Patients admitted for diseases of the appendix (ICD-10: K35-K38) or abdominal and pelvic pain (ICD-10: R10) who underwent an appendectomy (OPS: 5-470) were included. The study period included 6 weeks of German lockdown (16 March-26 April 2020) as well as 6 weeks before (03 February-15 March 2020) and after (27 April-07 June 2020). These periods were compared to the respective one in 2018 and 2019. RESULTS: The overall number of appendectomies was significantly reduced during the lockdown time in 2020 compared to that in 2018 and 2019. This decrease affects only appendectomies due to acute simple (ICD-10: K35.30, K35.8) and non-acute appendicitis (ICD-10: K36-K38, R10). Numbers for appendectomies in acute complex appendicitis remained unchanged. Female patients and in the age group 1-18 years showed the strongest decrease in number of cases. CONCLUSION: The lockdown in Germany resulted in a decreased number of appendectomies. This affected mainly appendectomies in simple acute and non-acute appendicitis, but not complicated acute appendicitis. The study gives no evidence that the confinement measures resulted in a deterioration of medical care for appendicitis.

Rates of Complications After Appendectomy in Children and Adolescents: Pediatric Surgical Compared to General Surgical Hospitals.

BACKGROUND: Appendectomies in children and adolescents are performed in Germany in pediatric surgical (PS) or general surgical hospitals (GS). The aim of this study is to evaluate whether the surgery in a PS or GS hospital has an influence on the postoperative course after appendectomy in children and adolescents. MATERIALS AND METHODS: Nationwide routine data from children and adolescents aged 1-17 y insured by the Local Health Insurance Fund who underwent appendectomy between 2014 and 2016 were analyzed (cohort study). Descriptive statistics were calculated both overall and in the two groups (PS and GS). Patients were additionally examined by age (1-5, 6-12, and 13-17 y), treatment (laparoscopic, open surgical, and conversion), and appendicitis type (nonacute: K36/K37/K38/R10, acute simple: K35.30/K35.8, and acute complex: K35.2/K35.31/K35.32). The influence of surgeon specialization on 90-d secondary surgery and 90-d general complications was assessed by multiple logistic regression. RESULTS: Altogether, 25,065 patients who underwent surgery in 83 PS and 906 GS hospitals were included. Logistic regression analysis revealed that PS was associated with a reduced risk of interventions in the 1-5- and 6-12-y age groups (odds ratio: 0.44, 0.62). Acute complex appendicitis, comorbidities, and open surgery significantly increased the risk for reintervention. PS was associated with an increased risk for complications in the 13-17-y age group (odds ratio: 1.66). CONCLUSIONS: PS and GS hospitals provided safe appendectomies in children and adolescents with low reintervention and complication rates. PS hospitals demonstrated advantages for patients in the 1-5- and 6-12-y age groups and GS hospitals for patients 13-17 y.

[Quality Assurance Using Administrative/Routine Data for Cholelithiasis - Changes Over Time and Current Status]. / Qualitätssicherung mit Routinedaten bei Cholelithiasis ­ Veränderungen und aktueller Stand.

Quality assurance using administrative/routine data (QSR) is a relatively new measure to assess outcome quality. This approach is methodologically distinct from external quality assurance, as well as from quality assurance based upon registries. Since 2011, QSR for cholelithiasis within AOK patients has been overseen by the Scientific Institute of the AOK (WIdO). Following the introduction of an expert panel in 2013, numerous changes were put into place, whereby the indicator rates for transfusion/bleeding, various complications as well as the overall indicator were reduced. Interestingly, the risk adjusted quality differences between hospitals remained solid.

Diagnostic pathology of early systemic cancer: ERBB2 gene amplification in single disseminated cancer cells determines patient survival in operable esophageal cancer.

Early metastatic dissemination and evolution of disseminated cancer cells (DCCs) outside the primary tumor is one reason for the failure of adjuvant therapies because it generates molecular genotypes and phenotypes different from primary tumors, which still underlie therapy decisions. Since ERBB2 amplification in esophageal DCCs but not in primary tumor cells predict outcome, we aimed to establish an assay with diagnostic reliability for single DCCs or circulating tumor cells. For this, we evaluated copy number alterations of more than 600 single DCCs from multiple cancer types to define reference regions suitable for quantification of target regions, such as ERBB2. We then compared ERBB2 quantitative PCR (qPCR) measurements with fluorescent in situ hybridization (FISH) data of various breast cancer cell lines and identified the aberration-calling threshold. The method was applied to two independent cohorts of esophageal cancer patients from Hamburg (n = 59) and Düsseldorf (n = 53). We found a high correlation between the single cell qPCR assay and the standard FISH assay (R = 0.98) and significant associations between amplification and survival for both patient cohorts (Hamburg (HH), p = 0.033; Düsseldorf (D), p = 0.052; pooled HH + D, p = 0.002) when applied to DCCs of esophageal cancer patients. Detection of a single ERBB2-amplified DCC was the most important risk factor for death from esophageal cancer (relative risk = 4.22; 95% CI = 1.91-9.32; p < 0.001). In our study, we detected ERBB2-amplified cells in 7% of patients. These patients could benefit from anti-ERBB2 targeting therapies.

Early dissemination seeds metastasis in breast cancer.

Accumulating data suggest that metastatic dissemination often occurs early during tumour formation, but the mechanisms of early metastatic spread have not yet been addressed. Here, by studying metastasis in a HER2-driven mouse breast cancer model, we show that progesterone-induced signalling triggers migration of cancer cells from early lesions shortly after HER2 activation, but promotes proliferation in advanced primary tumour cells. The switch from migration to proliferation was regulated by increased HER2 expression and tumour-cell density involving microRNA-mediated progesterone receptor downregulation, and was reversible. Cells from early, low-density lesions displayed more stemness features, migrated more and founded more metastases than cells from dense, advanced tumours. Notably, we found that at least 80% of metastases were derived from early disseminated cancer cells. Karyotypic and phenotypic analysis of human disseminated cancer cells and primary tumours corroborated the relevance of these findings for human metastatic dissemination.

Molecular profiling of single Sca-1+/CD34+,- cells--the putative murine lung stem cells.

Murine bronchioalveolar stem cells play a key role in pulmonary epithelial maintenance and repair but their molecular profile is poorly described so far. In this study, we used antibodies directed against Sca-1 and CD34, two markers originally ascribed to pulmonary cells harboring regenerative potential, to isolate single putative stem cells from murine lung tissue. The mean detection rate of positive cells was 8 per 10(6) lung cells. We then isolated and globally amplified the mRNA of positive cells to analyze gene expression in single cells. The resulting amplicons were then used for molecular profiling by transcript specific polymerase chain reaction (PCR) and global gene expression analysis using microarrays. Single marker-positive cells displayed a striking heterogeneity for the expression of epithelial and mesenchymal transcripts on the single cell level. Nevertheless, they could be subdivided into two cell populations: Sca-1(+)/CD34(-) and Sca-1(+)/CD34(+) cells. In these subpopulations, transcripts of the epithelial marker Epcam (CD326) were exclusively detected in Sca-1(+)/CD34(-) cells (p = 0.03), whereas mRNA of the mesenchymal marker Pdgfrα (CD140a) was detected in both subpopulations and more frequently in Sca-1(+)/CD34(+) cells (p = 0.04). FACS analysis confirmed the existence of a Pdgfrα positive subpopulation within Epcam(+)/Sca-1(+)/CD34(-) epithelial cells. Gene expression analysis by microarray hybridization identified transcripts differentially expressed between the two cell types as well as between epithelial reference cells and Sca-1(+)/CD34(+) single cells, and selected transcripts were validated by quantitative PCR. Our results suggest a more mesenchymal commitment of Sca-1(+)/CD34(+) cells and a more epithelial commitment of Sca-1(+)/CD34(-) cells. In summary, the study shows that single cell analysis enables the identification of novel molecular markers in yet poorly characterized populations of rare cells. Our results could further improve our understanding of Sca-1(+)/CD34(+,-) cells in the biology of the murine lung.

The side population phenomenon enriches for designated adrenocortical progenitor cells in mice.

Somatic adrenal stem cells are believed to reside in the periphery of the adrenal cortex throughout life for organ maintenance. Herein, we used the side population (SP) phenomenon to enrich for these progenitors, which made up to 0.01-0.64% of the total cell count. Microarray analysis revealed an expression profile of SP cells, which clearly differed from that of non-SP cells. However, a promising adrenal specific stem cell marker could not be identified. In vitro, SP cells could be maintained in long-term culture, whereas non-SP cells did not proliferate. After 4 weeks of culturing, immunohistochemistry revealed the expression of steroidogenic enzymes such as 3ß-HSD, StAR, and P450SCC, suggesting spontaneous differentiation. Interestingly, the quantity of SP cells was significantly diminished in Pbx1 haploinsufficient mice, suggesting a stem cell deficit. By contrast, the subcapsular zone of ACTH-deficient Tpit(-/-) mice was significantly wider compared with wild-type adrenals (Tpit(-/-) 259±10.7 vs Tpit(+/-) 100±12.3%; P<0.01). Accordingly, the number of SP cells in these mice was significantly higher (Tpit(-/-) 0.45±0.16 vs Tpit(+/-) 0.13±0.04%; P<0.004). ACTH treatment of these animals reverted the subcapsular zone width and the SP fraction back to normal (130±10.2%; P=0.33 and 0.09%), providing indirect evidence for a stem cell 'arrest' in Tpit(-/-) mice and the role of ACTH in adrenocortical stem cell modulation and differentiation.

Genomic data integration using guided clustering.

MOTIVATION: In biomedical research transcriptomic, proteomic or metabolomic profiles of patient samples are often combined with genomic profiles from experiments in cell lines or animal models. Integrating experimental data with patient data is still a challenging task due to the lack of tailored statistical tools. RESULTS: Here we introduce guided clustering, a new data integration strategy that combines experimental and clinical high-throughput data. Guided clustering identifies sets of genes that stand out in experimental data while at the same time display coherent expression in clinical data. We report on two potential applications: The integration of clinical microarray data with (i) genome-wide chromatin immunoprecipitation assays and (ii) with cell perturbation assays. Unlike other analysis strategies, guided clustering does not analyze the two datasets sequentially but instead in a single joint analysis. In a simulation study and in several biological applications, guided clustering performs favorably when compared with sequential analysis approaches. AVAILABILITY: Guided clustering is available as a R-package from http://compdiag.uni-regensburg.de/software/guidedClustering.shtml. Documented R code of all our analysis is included in the Supplementary Materials. All newly generated data are available at the GEO database (GSE29700). CONTACT: rainer.spang@klinik.uni-regensburg.de SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Transcriptome asymmetry within mouse zygotes but not between early embryonic sister blastomeres.

Transcriptome regionalization is an essential polarity determinant among metazoans, directing embryonic axis formation during normal development. Although conservation of this principle in mammals is assumed, recent evidence is conflicting and it is not known whether transcriptome asymmetries exist within unfertilized mammalian eggs or between the respective cleavage products of early embryonic divisions. We here address this by comparing transcriptome profiles of paired single cells and sub-cellular structures obtained microsurgically from mouse oocytes and totipotent embryos. Paired microsurgical spindle and remnant samples from unfertilized metaphase II oocytes possessed distinguishable profiles. Fertilization produces a totipotent 1-cell embryo (zygote) and associated spindle-enriched second polar body whose paired profiles also differed, reflecting spindle transcript enrichment. However, there was no programmed transcriptome asymmetry between sister cells within 2- or 3-cell embryos. Accordingly, there is transcriptome asymmetry within mouse oocytes, but not between the sister blastomeres of early embryos. This work places constraints on pre-patterning in mammals and provides documentation correlating potency changes and transcriptome partitioning at the single-cell level.

JVirGel 2.0: computational prediction of proteomes separated via two-dimensional gel electrophoresis under consideration of membrane and secreted proteins.

MOTIVATION: After the publication of JVirGel 1.0 in 2003 we got many requests and suggestions from the proteomics community to further improve the performance of the software and to add additional useful new features. RESULTS: The integration of the PrediSi algorithm for the prediction of signal peptides for the Sec-dependent protein export into JVirGel 2.0 allows the exclusion of most exported preproteins from calculated proteomic maps and provides the basis for the calculation of Sec-based secretomes. A tool for the identification of transmembrane helices carrying proteins (JCaMelix) and the prediction of the corresponding membrane proteome was added. Finally, in order to directly compare experimental and calculated proteome data, a function to overlay and evaluate predicted and experimental two-dimensional gels was included. AVAILABILITY: JVirGel 2.0 is freely available as precompiled package for the installation on Windows or Linux operating systems. Furthermore, there is a completely platform-independent Java version available for download. Additionally, we provide a Java Server Pages based version of JVirGel 2.0 which can be operated in nearly all web browsers. All versions are accessible at http://www.jvirgel.de