Is it possible to predict the severity of acute appendicitis? Reliability of predictive models based on easily available blood variables.

INTRODUCTION: Recent evidence confirms that the treatment of acute appendicitis is not necessarily surgical, and selected patients with uncomplicated appendicitis can benefit from a non-operative management. Unfortunately, no cost-effective test has been proven to be able to effectively predict the degree of appendicular inflammation as yet, therefore, patient selection is too often left to the personal choice of the emergency surgeon. Our paper aims to clarify if basic and readily available blood tests can give reliable prognostic information to build up predictive models to help the decision-making process. METHODS: Clinical notes of 2275 patients who underwent an appendicectomy with a presumptive diagnosis of acute appendicitis were reviewed, taking into consideration basic preoperative blood tests and histology reports on the surgical specimens. Variables were compared with univariate and multivariate analysis, and predictive models were created. RESULTS: 18.2% of patients had a negative appendicectomy, 9.6% had mucosal only inflammation, 53% had transmural inflammation and 19.2% had gangrenous appendicitis. A strong correlation was found between degree of inflammation and lymphocytes count and CRP/Albumin ratio, both at univariate and multivariate analysis. A predictive model to identify cases of gangrenous appendicitis was developed. CONCLUSION: Low lymphocyte count and high CRP/Albumin ratio combined into a predictive model may have a role in the selection of patients who deserve appendicectomy instead of non-operative management of acute appendicitis.

Is it Possible to Predict Non Sentinel Node Positivity on the Basis of mRNA Copy Numbers of CK19 Receptor in Breast Cancer?

AIMS: To determine if there is any correlation between the number of positive non-sentinel lymph nodes (NSLN) and the mRNA copy numbers of cytokeratin 19 receptor on one step nucleic acid amplification (OSNA) in the sentinel lymph node (SLN). METHODS: An 8-year retrospective study of consecutive patients who had primary surgery and sentinel node biopsy for breast cancer from January 2011 to December 2018 was carried out. All these patients had intra-operative analysis of sentinel lymph nodes by OSNA. Patients who had neoadjuvant chemotherapy or neoadjuvant endocrine therapy were excluded. RESULTS: There were 1159 patients with an age range of 24 to 90 years and a mean age of 63 years in this study. A total of 1324 SLNs were analyzed by OSNA. Macrometastasis was found in 120 patients and they underwent axillary lymph node dissection (ALND). A total of 2405 NSLNs were analyzed. Of the patients who had ALND, 51 (43%) patients had negative NSLNs and 69 (57%) had positive NSLNs. The mean mRNA copy numbers respectively for the 2 groups were 853,665 and 609,855. The difference between the means is not statistically significant (P = 0.82). Also the Receiver Operating Characteristic (ROC) Curve of the total CK-19 mRNA copy number for both groups-negative and positive NSLN were almost identical (Figure 3) indicating mRNA copy numbers cannot be used to discriminate between positive and negative non-sentinel lymph nodes. CONCLUSION: It is clear from our study that in patients who have ALND due to macromets on OSNA, there is no correlation between the total tumor load as represented by mRNA copy numbers and the likelihood of positive non-sentinel lymph nodes. We therefore cannot rely solely on the mRNA copy numbers to decide on ALND.

Construction of multifunctional fusion proteins with a laminin-derived short peptide to promote neural differentiation of mouse induced pluripotent stem cells.

There is growing interest in the functional roles of the extracellular matrix (ECM) in regulating the fate of pluripotent stem cells (PSCs). An artificially bioengineered ECM provides an excellent model for studying the molecular mechanisms underlying self-renewal and differentiation of PSCs, without multiple unknown and variable factors associated with natural substrates. Here, we have engineered multifunctional fusion proteins that are based on peptides from laminin, including p20, RGD, and elastin-like polypeptide (ELP), where laminin peptides work as cell adhesion molecules (CAMs) and ELP to promote anchorage. The functionality of these chimeric proteins, referred to as ERE-p20 and E-p20, was assessed by determining their ability to immobilize cells on a hydrophobic polystyrene surface, improve mouse induced pluripotent stem cells (miPSCs) attachment, and promote miPSC differentiation to neural progenitors. ERE-p20 and E-p20 proteins showed hydrophobic binding saturation to the polystyrene plates around 500 nM (2.39 µg/cm2 ) and 750 nM (2.27 µg/cm2 ) protein concentrations, respectively. The apparent maximum cell binding to ERE-p20 and E-p20 was approximately 81% and 73%, respectively, relative to gelatin. For neural precursors, neurite outgrowth was enhanced by the presence of RGD and p20 peptides. The expression levels of neuronal marker protein MAP2 were upregulated approximately 2.5-fold and threefold by ERE-p20 and E-p20, respectively, relative to laminin. Overall, we have shown that elastin-mimetic fusion proteins consisting of p20 with and without RGD peptides are able to induce neuronal differentiation. In conclusion, our newly designed bioengineered fusion proteins allow preparation of specific bioactive matrices or coating/scaffold for miPSCs differentiation.