Color Analysis of Merkel Cell Carcinoma: A Comparative Study with Cherry Angiomas, Hemangiomas, Basal Cell Carcinomas, and Squamous Cell Carcinomas.

Merkel cell carcinoma (MCC) is recognized as one of the most malignant skin tumors. Its rarity might explain the limited exploration of digital color studies in this area. The objective of this study was to delineate color alterations in MCCs compared to benign lesions resembling MCC, such as cherry angiomas and hemangiomas, along with other non-melanoma skin cancer lesions like basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), utilizing computer-aided digital color analysis. This was a retrospective study where clinical images of the color of the lesion and adjacent normal skin from 11 patients with primary MCC, 11 patients with cherry angiomas, 12 patients with hemangiomas, and 12 patients with BCC/SCC (totaling 46 patients) were analyzed using the RGB (red, green, and blue) and the CIE Lab color system. The Lab color system aided in estimating the Individual Typology Angle (ITA) change in the skin, and these results are documented in this study. It was demonstrated that the estimation of color components can assist in the differential diagnosis of these types of lesions because there were significant differences in color parameters between MCC and other categories of skin lesions such as hemangiomas, common skin carcinomas, and cherry hemangiomas. Significant differences in values were observed in the blue color of RGB (p = 0.003) and the b* parameter of Lab color (p < 0.0001) of MCC versus cherry angiomas. Similarly, the mean a* value of Merkel cell carcinoma (MCC) compared to basal cell carcinoma and squamous cell carcinoma showed a statistically significant difference (p < 0.0001). Larger prospective studies are warranted to further validate the clinical application of these findings.

Biomechanical explanation of W-plasty effectiveness using a finite element method approach.

The finite element method has often been used to assist analyzing local flaps in terms of deformation and stress measurements as it takes into account complex skin properties. We, herein, present an isotropic two-dimensional finite element skin model applied to the W-plasty method to demonstrate that the good outcomes of W-plasty should be attributed to the geometry itself, as it generates lower stresses. The skin was modeled as a two-dimensional (2D) planar geometry. The model was created and solved as a plane stress problem. The model was based on simulation of the loading and stitching of W-plasties of various angles. Each central triangular flap was segmented in nine triangular elements. The stitching was modeled with one suture at the top of each triangular flap with the center of the opposite corner. X- and Y-axis stresses and shearing stresses Txy in the elements involved in the broken stitching line, show lower stresses than the elements behind the stitching line. Interestingly, in the triangular flaps, the stresses were clearly lower than those of their neighboring areas. The maximum compressive stresses in the 2D model we used, correspond to the dog ears. We conclude that the effectiveness of W-plasty should be attributed not only to the scar orientation in relation to the relaxed tension skin lines but also to the special design of the triangular flaps used. This finding assists the general understanding of the method and should be taken into account by the clinician during flap designing.

A Six-Year Retrospective Study of Microbiological Characteristics and Antimicrobial Resistance in Specimens from a Tertiary Hospital's Surgical Ward.

Surgery has revolutionized the practice of medicine by allowing the treatment of conditions amenable to conservative medical management with some of them pathophysiologically involving the prevalence of pathogenic microorganisms. On the other hand, infections such as surgical site infections or urinary tract infections may complicate patients hospitalized in surgical wards leading to considerable morbidity, mortality, and increased healthcare-associated costs. The aim of this study was to present the microbiological characteristics and antimicrobial resistance of all isolates identified in microbiological specimens from a surgical ward of a tertiary hospital in Greece during a six-year period. Only specimens that yielded at least one microorganism were included in the analysis. In total, 1459 strains in 789 positive cultures were isolated. The most common sample sent to the microbiology department was pus from surgical wounds. The most common pathogens among all 1459 strains isolated were Enterobacterales at 33% (n = 482), however, the most common genus was Enterococcus at 22.3% (n = 326). Antimicrobial resistance against third-generation cephalosporins was 23% (n = 111/482) among Enterobacterales, while, the rate of vancomycin-resistant enterococci (VRE) was 18.5% (n = 60/324) among Enterococcus species and was increasing in the last years of the study. Antimicrobial resistance of Acinetobacter baumannii to carbapenems was 68.8% (n = 11/16), which was lower than the corresponding rate in other wards in Greece. The antimicrobial resistance rates noted herein raise questions regarding the appropriateness of currently suggested antimicrobials in guidelines and imply that a revision could be required. Practicing clinicians should always be aware of local microbiological data that allow the selection of appropriate antimicrobials for the management of infections. Finally, the increasing rates of VRE noted herein mandate further actions from the point of infection control and antimicrobial stewardship.

Comparative activities of ampicillin and teicoplanin against Enterococcus faecalis isolates.

BACKGROUND: Enterococcus faecalis remains one of the most common pathogens causing infection in surgical patients. Our goal was to evaluate the antibiotic resistance of E. faecalis, causing infections in a surgical clinic, against two antibacterial drugs, ampicillin and teicoplanin. One commonly administered in the past for such infections, ampicillin, and another newer, teicoplanin, which demonstrated exceptionally good efficacy. METHODS: Data from 1882 isolates were retrieved from the microbiology department database during two 5-year periods. Standard biochemical methods were employed for the identification of the isolates. The prevalence of E. faecalis among patients with clinical evidence of infection in a surgical oncology ward was assessed. Confidence interval (CI) as well as standard error (SE) were calculated. Moreover, the annual incidence of E. faecalis infections in this surgical ward was recorded. The susceptibility of E. faecalis to ampicillin and teicoplanin was studied and compared using Fisher's exact test. RESULTS AND CONCLUSION: Results showed that the incidence of E. faecalis infections in the surgical clinic was increasing. Ampicillin, in the later year period, was not statistically different from teicoplanin in treating E. faecalis infections. Consequently, ampicillin seems currently to be an effective antibiotic against such infections that could be used as empiric therapy.

Computer-aided clinical image analysis as a predictor of sentinel lymph node positivity in cutaneous melanoma.

BACKGROUND: Delays in sentinel lymph node (SLN) biopsy may affect the positivity of non-SLNs. For these reasons, effort is being directed at obtaining reliable information regarding SLN positivity prior to surgical excision. However, the existing tools, e.g., dermoscopy, do not recognize statistically significant predictive criteria for SLN positivity in melanomas. AIM: To investigate the possible association of computer-assisted objectively obtained color, color texture, sharpness and geometry variables with SLN positivity. METHODS: We retrospectively reviewed and analyzed the computerized medical records of all patients diagnosed with cutaneous melanoma in a tertiary hospital in Germany during a 3-year period. The study included patients with histologically confirmed melanomas with Breslow > 0.75 mm who underwent lesion excision and SLN biopsy during the study period and who had clinical images shot with a digital camera and a handheld ruler aligned beside the lesion. RESULTS: Ninety-nine patients with an equal number of lesions met the inclusion criteria and were included in the analysis. Overall mean (± standard deviation) age was 66 (15) years. The study group consisted of 20 patients with tumor-positive SLN (SLN+) biopsy, who were compared to 79 patients with tumor-negative SLN biopsy specimen (control group). The two groups differed significantly in terms of age (61 years vs 68 years) and histological subtype, with the SLN+ patients being younger and presenting more often with nodular or secondary nodular tumors (P < 0.05). The study group patients showed significantly higher eccentricity (i.e. distance between color and geometrical midpoint) as well as higher sharpness (i.e. these lesions were more discrete from the surrounding normal skin, P < 0.05). Regarding color variables, SLN+ patients demonstrated higher range in all four color intensities (gray, red, green, blue) and significantly higher skewness in three color intensities (gray, red, blue), P < 0.05. Color texture variables, i.e. lacunarity, were comparable in both groups. CONCLUSION: SLN+ patients demonstrated significantly higher eccentricity, higher sharpness, higher range in all four color intensities (gray, red, green, blue) and significantly higher skewness in three color intensities (gray, red, blue). Further prospective studies are needed to better understand the effectiveness of clinical image processing in SLN+ melanoma patients.

MAGE: An Open-Source Tool for Meta-Analysis of Gene Expression Studies.

MAGE (Meta-Analysis of Gene Expression) is a Python open-source software package designed to perform meta-analysis and functional enrichment analysis of gene expression data. We incorporate standard methods for the meta-analysis of gene expression studies, bootstrap standard errors, corrections for multiple testing, and meta-analysis of multiple outcomes. Importantly, the MAGE toolkit includes additional features for the conversion of probes to gene identifiers, and for conducting functional enrichment analysis, with annotated results, of statistically significant enriched terms in several formats. Along with the tool itself, a web-based infrastructure was also developed to support the features of this package.

Computer-aided clinical image analysis for non-invasive assessment of tumor thickness in cutaneous melanoma.

OBJECTIVE: Computerized clinical image analysis is shown to improve diagnostic accuracy for cutaneous melanoma but its effectiveness in preoperative assessment of melanoma thickness has not been studied. The aim of this study, is to explore how melanoma thickness correlates with computer-assisted objectively obtained color and geometric variables. All patients diagnosed with cutaneous melanoma with available clinical images prior to tumor excision were included in the study. All images underwent digital processing with an automated non-commercial software. The software provided measurements for geometrical variables, i.e., overall lesion surface, maximum diameter, perimeter, circularity, eccentricity, mean radius, as well as for color variables, i.e., range, standard deviation, coefficient of variation and skewness in the red, green, and blue color space. RESULTS: One hundred fifty-six lesions were included in the final analysis. The mean tumor thickness was 1.84 mm (range 0.2-25). Melanoma thickness was strongly correlated with overall surface area, maximum diameter, perimeter and mean lesion radius. Thickness was moderately correlated with eccentricity, green color and blue color. We conclude that geometrical and color parameters, as objectively extracted by computer-aided clinical image processing, may correlate with tumor thickness in patients with cutaneous melanoma. However, these correlations are not strong enough to reliably predict tumor thickness.

Apocrine and eccrine hidrocystomas: a clinicopathological study.

INTRODUCTION: Eccrine and apocrine hidrocystomas are uncommon, benign, cystic proliferations of the sweat glands usually located on the head and neck area. OBJECTIVES: To describe the key clinical and histopathological characteristics of a large series of hidrocystomas in Greece to improve diagnostic accuracy, and to perform a historical review of the medical term hidrocystoma. METHODS: A case series of 22 hidrocystomas from 20 consecutive patients treated with surgery at University Hospital of Heraklion in Crete, Greece, from January 1, 1998 to January 1, 2020 was performed along with a comprehensive historical literature review of the term hidrocystoma and its corresponding term hydatis from ancient Greek literature to the present. Data were obtained from medical records. All patients had a histopathologically confirmed diagnosis of hidrocystoma. Formalin-fixed paraffin-embedded (FFPE) sections of 22 tumors of the 20 consecutive patients were retrieved from the pathology laboratory archive and stained for SMA, p63, and GCDFP-15 with immunochemistry and periodic acid-Schiff (PAS) histochemical stain. RESULTS: Overall, 22 hidrocystomas (11 apocrine and 11 eccrine hidrocystomas) surgically excised from 20 patients were included in this study. Of the 20 patients, 10 (50%) were male and 10 (50%) were female, with a mean age of 56 ± 15 years. Hidrocystomas commonly occurred on the eyelids (73%), inner canthus (9%), eyebrow (4.5%), neck (4.5%), nose (4.5%), and ear (4.5%). All apocrine hidrocystomas stained positive for SMA, GCDFP-15, CAM 5.2, PAS, and PAS-D. No recurrence was observed. CONCLUSIONS: Here we have presented the clinicopathological characteristics of the largest case series of hidrocystomas in Europe and the Mediterranean region. Only apocrine hidrocystomas stained positive for SMA, GCDFP-15, CAM 5.2, PAS, and PAS-D.

A statistical analysis for RF-EMF exposure levels in sensitive land use: A novel study in Greek primary and secondary education schools.

BACKGROUND: The increasing popularity of mobile phones and the expansion of network infrastructure in Greece have given rise to public concerns about potential adverse health effects on sensitive groups, such as children, from long-term radio-frequency (RF) electromagnetic fields (EMFs) exposure. According to Greek law the RF limit values for sensitive land use (schools, hospitals, etc) have been set to 60% of those recommended by EU standard and 70% for the general population. AIMS: The objective of this study is to estimate mean RF-EMF exposure levels of Greek primary and secondary edu-cation schools located in urban environments. METHODS: In selecting the minimum sample size we observed that the variance of the random variable was unknown, as there has been no similar previous study in Greece with schools as the target population. For this reason, a pilot study was conducted in 65 schools in order to estimate the standard deviation of the population and use that value to calculate the minimum sample size. Using a random machine num-ber generator contracted in R based on pseudo-random number algorithms, we obtained a sample of 492 schools in order to estimate the mean value for RF-EMF radiation sources in the 27 MHz-3GHz range in schools within urban environments in Greece. RESULTS: We have performed the appropriate hypothesis test to get that there is sufficient evidence at the α = 0.05 level to conclude that the mean value for RF-EMF radiation sources in the 27 MHz-3GHz range, in schools within urban environments in Greece, is equal to 0.42 V/m, also a 95% confidence interval for the mean value is (0.4024, 0.4395)] with central value equal to the sample mean 0.4209. CONCLUSION: In conclusion, the exposure level in the locations tested are both below 60% of the highest limit set by ICNIRP (International Commision on Non-Ionizing Radiation Protection) regarding sensitive land use.