Can thickness of subcutaneous fat tissue limit emergency percutaneous cricothyrotomy?

Background Needle cricothyrotomy is a method of maintaining airways in emergency situations. One of identified factors that can make this procedure difficult to perform is ‘difficult neck anatomy’ or short obese neck. Due to the growing problem of obesity, we decided to estimate feasibility of needle cricothyrotomy by measuring the thickness of neck fat tissue in the population. Evaluation of this method is important because it is the only method that can be legally performed by paramedics in Poland. The aim of the study was to estimate feasibility of needle cricoidectomy by evaluating the percentage of population in which the thickness of subcutaneous fat tissue could potentially limit or complicate such a procedure. Methods In this retrospective study we reviewed CT scans of the neck from a database at the Department of Radiology, University Hospital in Cracow. 550 CT scans met inclusion criteria: age of patient over 18 years old, lack of any lesions altering anatomy of measured region of neck, the first CT scan of patient. 50.36% of patients were women. Median age was 61 years (range 18 – 93). The distance from the skin surface at the level of the lower edge of the thyroid cartilage to the cricothyroid ligament (surface - ligament distance, SLD) was measured. Statistical analysis of the data was performed using R software (R version 4.0.3). Results Median SLD was 1.41 (1.01 - 2.04). Subcutaneous fat tissue was thicker than maximal depth of application of cricothyrotomy (3cm) device in 31 patients (5.64%). Conclusions Performing needle cricothyrotomy may be limited in a considerable percentage of population (5.64%).

Vascularization of Microvascular Fragment Isolates from Visceral and Subcutaneous Adipose Tissue of Mice

Background: Adipose tissue-derived microvascular fragments (MVF) represent effective vascularization units for tissue engineering. Most experimental studies in rodents exclusively use epididymal adipose tissue as a visceral fat source for MVF isolation. However, in future clinical practice, MVF may be rather isolated from liposuctioned subcutaneous fat tissue of patients. Therefore, we herein compared the vascularization characteristics of MVF isolates from visceral and subcutaneous fat tissue of murine origin. Methods: MVF isolates were generated from visceral and subcutaneous fat tissue of donor mice using two different enzymatic procedures. For in vivo analyses, the MVF isolates were seeded onto collagen-glycosaminoglycan scaffolds and implanted into full-thickness skin defects within dorsal skinfold chambers of recipient mice. Results: By means of the two isolation procedures, we isolated a higher number of MVF from visceral fat tissue when compared to subcutaneous fat tissue, while their length distribution, viability and cellular composition were comparable in both groups. Intravital fluorescence microscopy as well as histological and immunohistochemical analyses revealed a significantly reduced vascularization of implanted scaffolds seeded with subcutaneous MVF isolates when compared to implants seeded with visceral MVF isolates. Light and scanning electron microscopy showed that this was due to high amounts of undigested connective tissue within the subcutaneous MVF isolates, which clogged the scaffold pores and prevented the interconnection of individual MVF into new microvascular networks. Conclusion: These findings indicate the need for improved protocols to generate connective tissue-free MVF isolates from subcutaneous fat tissue for future translational studies.

Association of the ratio of visceral-to-subcutaneous fat volume with renal function among patients with primary aldosteronism

Patients with primary aldosteronism have a higher risk of chronic kidney disease. Visceral fat tissue is hypothesized to stimulate the adrenal glands to overproduce aldosterone, and aldosterone promotes visceral fat tissue to produce inflammatory cytokines. However, it is unclear whether the volume of accumulated visceral fat tissue is associated with renal impairment among patients with hyperaldosteronism. We conducted a single-center cross-sectional study to assess the association between the estimated glomerular filtration rate and the ratio of the visceral-to-subcutaneous fat volume calculated by computed tomography. One hundred eighty patients with primary aldosteronism were enrolled. The mean ± SD age was 52.7 ± 11.0 years, and 60.0% were women. The ratio of visceral-to-subcutaneous fat volume was highly correlated with the estimated glomerular filtration rate (r = 0.49, p < 0.001). In multiple linear regression models, the ratio of visceral-to-subcutaneous fat tissue volume was significantly associated with the estimated glomerular filtration rate (estimates: −4.56 mL/min/1.73 m² per 1-SD), and there was an interaction effect between the plasma aldosterone concentration and the ratio of visceral-to-subcutaneous fat volume (p < 0.05). The group with a higher plasma aldosterone concentration exhibited a steeper decline in eGFR than the lower plasma aldosterone concentration group when the ratio increased. The ratio of visceral-to-subcutaneous fat tissue volume was an independent risk factor for renal dysfunction. This association increased in the presence of a high plasma aldosterone concentration. Clinicians should pay attention to the ratio of visceral-to-subcutaneous fat tissue volume and encourage primary aldosteronism patients to improve their lifestyle in addition to treating renin-aldosterone activity.

Epigenetic modifications underlie the differential adipogenic potential of preadipocytes derived from human subcutaneous fat tissue

Aim: Ceiling culture-derived preadipocytes (ccdPAs) and adipose-derived stem cells (ASCs) can be harvested from human subcutaneous fat tissue using the specific gravity method. Both cell types possess a similar spindle shape without lipid droplets. We previously reported that ccdPAs have a higher adipogenic potential than ASCs, even after a 7-week culture. We performed a genome-wide epigenetic analysis to examine the mechanisms contributing to the adipogenic potential differences between ccdPAs and ASCs. Materials and Methods: Methylation analysis of cytosines followed by guanine (CpG) using a 450K BeadChip was performed on human ccdPAs and ASCs isolated from three metabolically healthy females. Chromatin immunoprecipitation sequencing (ChIP-seq) was performed to evaluate trimethylation at lysine 4 of histone 3 (H3K4me3). Results: Unsupervised machine learning using t-distributed stochastic neighbor embedding (tSNE) to interpret 450,000-dimensional methylation assay data showed that the cells were divided into ASC and ccdPA groups. In KEGG pathway analysis of 1,543 genes with differential promoter CpG methylation, the peroxisome proliferator-activated receptor (PPAR) and adipocytokine signaling pathways ranked in the top 10 pathways. In the PPAR gamma gene, H3K4me3 peak levels were higher in ccdPAs than in ASCs, whereas promoter CpG methylation levels were significantly lower in ccdPAs than in ASCs. Similar differences in promoter CpG methylation were also seen in the fatty acid-binding protein 4 (FABP4) and leptin genes. Conclusion: We analyzed the epigenetic status of adipogenesis-related genes as a potential mechanism underlying the differences in adipogenic differentiation capability between ASCs and ccdPAs.

POS0422 PANNICULITIS AS A MANIFESTATION OF AN AUTOIMMUNE/AUTOINFLAMMATORY DISEASE

Background:ASIA syndrome or Schonfeld syndrome is an autoimmune/inflammatory condition induced by adjuvants in genetically susceptible individuals with the development of rheumatic diseases (RD), multiple sclerosis, sarcoidosis, and others.Objectives:to characterize the symptoms of panniculitis (Pn) associated with ASIA-syndromeMethods:Within 7 years, ASIA syndrome was diagnosed in 12 women, average age 37.2±7.4, with a referral diagnosis of “Erythema Nodosum” or “Panniculitis”. The duration of the disease was 16.7±3.9 months. In addition to general clinical study, the serum concentration of α-1 antitrypsin, amylase, lipase, ferritin, creatine phosphokinase (CPK), immunological parameters (ANP-Hep2, dsDNA, C3 and C4, CRP, ANCA, Scl-70, antibodies to cardiolipins G and M), computed tomography of the chest organs, pathomorphological and immunohistochemical examination of a biopsy specimen of skin with subcutaneous fat tissue (SFA) from the affected areas.Results:The development of ASIA syndrome was preceded by gluteoplasty using propantriol-1,2,3 (in 4 patients), liposuction (2), biorevitalization with hyaluronic acid (2) and endoprosthetics with breast implants (2), bone metal construction (1) and mesh hernioplasty (1). The clinical picture of Pn was characterized by generalized red-purple painful (VAS pain 55.8±17.3 mm) subcutaneous indurations on the upper limbs and trunk (in 100% of cases), face (16.6%) and lower limbs (33.3%), with ulceration and oily fluid leakage (58.6%). The saucer symptom was recorded in 83.3% of the observed patients. In 66.6% of cases, fever and articular syndrome were observed, in 41.6% – myasthenic syndrome and lymphadenopathy, in 8.3% – xerophthalmia, keratoconjunctivitis dry, xerostomia and recurrent parotitis. In blood tests, leukopenia (up to 2.0x109/l) was identified in 33.3% of patients, a significant increase in the level of creatinine phosphakinase – in 16,6%, a two or more times increase in ESR and CRP – in 100%. All patients demonstrated immunological changes. The morphological picture of the skin and SFA in 75% of cases resembled lobular Pn, in 8.3% – tumor lymphocytes with the immunophenotype of cytotoxic T-lymphocytes: CD3+, CD8+ were detected. The results obtained allowed confirming RD in 8 patients: systemic lupus erythematosus and idiopathic lobular panniculitis in 2 patients (respectively) and 1 in dermatomyositis, systemic scleroderma of Sjogren’s disease, mixed connective tissue disease. One case was diagnosed with sarcoidosis and T-cell lymphoma. In 2 patients after the liposuction procedure the course of Pn was reversible.Conclusion:Diagnosis of Pn associated with ASIA syndrome is a complex task that requires a multidisciplinary approach to verify the diagnosis and treatment tactics.Disclosure of Interests:None declared

Imaging findings of cutaneous angiosarcoma of the scalp: Comparison with cutaneous squamous cell carcinoma

Purpose This study aimed to evaluate imaging findings of cutaneous angiosarcoma (cAS) of the scalp compared with those of cutaneous squamous cell carcinoma (cSCC). Methods This study included 15 patients with primary cAS and 10 with primary cSCC of the scalp. Seven patients with cAS and eight with cSCC underwent magnetic resonance imaging, and 11 patients with cAS and eight with cSCC underwent 18F-fluorodeoxyglucose–positron emission tomography/computed tomography imaging. Imaging findings for both pathologies were retrospectively reviewed and compared. Results All 15 cAS cases were elevated lesions with an obtuse angle, invading the subcutaneous fat tissue. Multiple lesions were observed in only five cAS cases (33%) and no cSCC cases. Maximum diameter-to-height ratio was significantly higher in cAS than in cSCC (3.3 ± 1.0 versus 2.3 ± 0.6; p < 0.01). On T2-weighted images, intratumoral hypointensity (86% versus 13%; p < 0.01) and mixed hyper- and hypointensity (71% versus 0%; p < 0.01) were observed more frequently in cAS than in cSCC. No significant differences were observed between cAS and cSCC regarding flow void (29% versus 25%; p = 0.656). Maximum standardized uptake values were marginally significantly lower in cAS than in cSCC (5.6 ± 3.1 versus 10.5 ± 6.6; p = 0.078). Conclusions Cases of cAS of the scalp always exhibited flat elevated lesions with invasion of the subcutaneous fat tissue. Compared with cSCC, intratumoral hypointensity and mixed hyper- and hypointensity on T2-weighted images were more frequent in cAS. These findings will help with the differential diagnosis of cAS.

Lupus mastitis

Lupus mastitis Systemic lupus erythematosus (SLE) infrequently presents itself as lupus panniculitis. In lupus panniculitis the subcutaneous fat tissue is involved in the inflammatory process. Lupus mastitis is again a rare variant of lupus panniculitis, probably caused by an immune-mediated inflammatory process. In literature on the topic we can find 30 cases of lupus mastitis in men and women. Lupus mastitis may present like a breast lesion suspected to be malignant, clinically and radiologically. In the differential diagnosis we consider inflammatory breast cancer, subcutaneous panniculitis-like T-cell lymphoma (SPTL) and diabetes mastopathy. With a medical history of SLE and signs of inflammation of the skin above the lesion however, a diagnosis of lupus mastopathy is more presumable. Medical treatment seems more indicated in lupus mastitis, because delayed healing after surgical procedures is often reported. Even though methylprednisolone and chloroquine give clinical improvement, they need to be repeated often because of a high risk of relapse.

Effect of 8-Week Endurance Training on the Content of Mtor and SREBP1 Proteins in Subcutaneous Fat Tissue in Obese Type 2 Diabetic Male Sprague-Dawley Rats

Introduction: The mTOR and SREBP1 proteins play an important role important in the regulation and metabolism of adipose tissue that can be activated through the mTORC1 pathway. The purpose of the present study was to investigate the effect of 8 weeks endurance training on the content of mTOR and SREBP1 proteins in subcutaneous fat tissue in obese type 2 diabetic male Sprague-Dawley rats. Methods: In this experimental study, 16 three-month-old Sprague-Dawley rats with a mean weight of 300±20 g were selected. After diabetic induction with Streptozotocin and Nicotinamide, rats were randomly assigned to two groups, diabetic training (n=8) and diabetic control (n=8). The training group trained for 4 days a week in accordance with the training program for 8 weeks, while the control group did not have any training program. The independent t-test in SPSS software ver. 19 was used to analyze the data. Results: There was a significant increase in the content of mTOR (p<0.0001) and SREBP1 (p<0.0001) proteins in the training group compared to control; The control group weight increased (p<0.003) and training group (p<0.002) significantly decreased at the end of the eighth week compared to the first week. The blood glucose increased in the control group (p<0.001) and decreased in the exercise group (p<0.0001) in the eighth week compared to the first week. Conclusion: Endurance training can adjust the weight, blood glucose and proteins content of mTOR and SREBP1; Therefore, endurance training can be an important factor in controlling and regulating fat tissue metabolism; this type of training can be effective for obese subjects with type 2 diabetes.