Abdominal Superficial Subcutaneous Fat

OBJECTIVE: Unlike visceral adipose tissue (VAT), the association between subcutaneous adipose tissue (SAT) and obesity-related morbidity is controversial. In patients with type 2 diabetes, we assessed whether this variability can be explained by a putative favorable, distinct association between abdominal superficial SAT (SSAT) (absolute amount or its proportion) and cardiometabolic parameters. RESEARCH DESIGN AND METHODS: We performed abdominal magnetic resonance imaging (MRI) in 73 patients with diabetes (mean age 58 years, 83% were men) and cross-sectionally analyzed fat distribution at S1-L5, L5-L4, and L3-L2 levels. Patients completed food frequency questionnaires, and subgroups had 24-h ambulatory blood pressure monitoring and 24-h ambulatory electrocardiography. RESULTS: Women had higher %SSAT (37 vs. 23% in men; P < 0.001) despite a similar mean waist circumference. Fasting plasma glucose (P = 0.046) and HbA1c (P = 0.006) were both lower with increased tertile of absolute SSAT. In regression models adjusted for age, waist circumference, and classes of medical treatments used in this patient population, increased %SSAT was significantly associated with decreased HbA1c (β = −0.317; P = 0.013), decreased daytime ambulatory blood pressure (β = −0.426; P = 0.008), and increased HDL cholesterol (β = 0.257; P = 0.042). In contrast, increased percent of deep SAT (DSAT) was associated with increased HbA1c (β = 0.266; P = 0.040) and poorer heart rate variability parameters (P = 0.030). Although total fat and energy intake were not correlated with fat tissue distribution, increased intake of trans fat tended to be associated with total SAT (r = 0.228; P = 0.05) and DSAT (r = 0.20; P = 0.093), but not with SSAT. CONCLUSIONS: Abdominal SAT is composed of two subdepots that associate differently with cardiometabolic parameters. Higher absolute and relative distribution of fat in abdominal SSAT may signify beneficial cardiometabolic effects in patients with type 2 diabetes

Uncoupling the Trade-Off between Somatic Proteostasis and Reproduction in Caenorhabditis elegans Models of Polyglutamine Diseases

Caenorhabditis elegans somatic protein homeostasis (proteostasis) is actively remodeled at the onset of reproduction. This proteostatic collapse is regulated cell-nonautonomously by signals from the reproductive system that transmit the commitment to reproduction to somatic cells. Here, we asked whether the link between the reproductive system and somatic proteostasis could be uncoupled by activating downstream effectors in the gonadal longevity cascade. Specifically, we examined whether over-expression of lipl-4 (lipl-4(oe)), a target gene of the gonadal longevity pathway, or increase in arachidonic acid (AA) levels, associated with lipl-4(oe), modulated proteostasis and reproduction. We found that lipl-4(oe) rescued somatic proteostasis and postponed the onset of aggregation and toxicity in C. elegans models of polyglutamine (polyQ) diseases. However, lipl-4(oe) also disrupted fatty acid transport into developing oocytes and reduced reproductive success. In contrast, diet supplementation of AA recapitulated lipl-4(oe)-mediated proteostasis enhancement in wild type animals but did not affect the reproductive system. Thus, the gonadal longevity pathway mediates a trade-off between somatic maintenance and reproduction, in part by regulating the expression of genes, such as lipl-4, with inverse effects on somatic maintenance and reproduction. We propose that AA could uncouple such germline to soma crosstalk, with beneficial implications protein misfolding diseases

Single Surgeon versus Co-Surgeons in Primary Total Joint Arthroplasty: Does “Two Is Better than One” Apply to Surgeons?

Background: As the demand for total joint arthroplasties (TJA) increases steadily, so does the pressure to train future surgeons and, at the same time, achieve optimal outcomes. We aimed to identify differences in operative times and short-term surgical outcomes of TJAs performed by co-surgeons versus a single attending surgeon. Methods: A retrospective analysis of 597 TJAs, including 239 total hip arthroplasties (THAs) and 358 total knee arthroplasties (TKAs) was conducted. All operations were performed by one of four fellowship-trained attending surgeons as the primary surgeon. The assisting surgeons were either attendings or residents. Results: In 51% of THA and in 38% of TKA, two attending surgeons were scrubbed in. An additional scrubbed-in attending was not found to be beneficial in terms of surgical time reduction or need for revision surgeries within the postoperative year. This was also true for THAs and for TKAs separately. An attending co-surgeon was associated with a longer hospital stay (p = 0.028). Surgeries performed by fewer surgeons were associated with a shorter surgical time (p = 0.036) and an increased need for blood transfusion (p = 0.033). Neither the rate of intraoperative complications nor revisions differed between groups, regardless of the number of attending surgeons scrubbed in or the total number of surgeons. Conclusion: A surgical team comprised of more than a single attending surgeon in TJAs was not found to reduce surgical time, while the participation of residents was not related with worse patient outcomes

F-18 FDG PET differentiation of benign from malignant chondroid neoplasms: a systematic review of the literature

Discriminating among benign chondroid tumors, low-grade chondrosarcomas, and grade 2/3 chondrosarcomas is frequently difficult with standard imaging modalities. We systematically reviewed the literature to determine the performance of PET-CT in making this distinction. A systematic review was performed identifying 811 PubMed- and Embase-indexed articles containing combinations of "chondrosarcoma," "enchondroma," "chondroid," "cartilage" and "PET/CT," "PET," "positron." Eight articles including 166 lesions were included. Age, gender, tumor size, histologic grade, and SUVmax values were extracted for individual lesions when possible and otherwise recorded as aggregated data. Comparisons in SUVmax among benign, low-grade, and intermediate-/high-grade chondroid neoplasms were made. Individual SUVs were available for 101 lesions; 65 additional lesions were reported as aggregated data. There were 101 malignant and 65 benign tumors. Benign tumors were seen more frequently in females (p = 0.04, Fischer's exact test), but malignancy was not associated with age or lesion size. SUVmax was lower for benign (1.6 ± 0.7) than malignant tumors (4.4 ± 2.5) (p < 0.0001, t-test). SUVmax was lower for grade 0/1 (2.0 ± 0.7) than grade 2/3 (6.0 ± 3.2) (p < 0.0001, t-test). Increasing SUVmax correlated with higher grade chondroid tumors (Spearman's rank, ρ = 0.78). SUVmax ≥4.4 was 99% specific for grade 2/3 chondrosarcoma. SUVmax correlates with histologic grade in intraosseous chondroid neoplasms; very low SUVmax supports a diagnosis of benign tumor, while elevated SUVmax is suggestive of higher grade chondrosarcoma

Denosumab treatment for giant-cell tumor of bone: a systematic review of the literature

Denosumab is a human monoclonal antibody (mAb) that specifically inhibits tumor-associated bone lysis through the RANKL pathway and has been used as neoadjuvant therapy for giant-cell tumor of bone (GCTB) in surgical as well as non-surgical cases. The purpose of this systematic review of the literature, therefore, is to investigate: (1) demographic characteristics of patients affected by GCTBs treated with denosumab and the clinical impact, as well as, possible complications associated with its use (2) oncological outcomes in terms of local recurrence rate (LRR) and development of lung metastasis, and (3) characteristics of its treatment effect in terms of clinical, radiological, and histological response.A systematic review of the literature was conducted using PubMed, EMBASE, and COCHRANE search including the following terms and Boolean operators: “Denosumab” AND “primary bone tumor”, “denosumab” AND “giant cell tumor”, “denosumab” AND “treatment”, and finally, “denosumab” AND “giant cell tumor” AND “treatment” since 2000. After applying inclusion and exclusion criteria, a total of 19 articles were included. The quality of the included studies was assessed using STROBE for the assessment of observational studies.A total of 1095 patients were included across all 19 studies. Across all the studies included, there were 615 females and 480 males. The mean patient age was 33.7 ± 8.3 years when starting the denosumab treatment. The pooled weighted local recurrence rate was 9% (95% CI 6–12%) and the pooled weighted metastases rate was 3% (95% CI 1–7%). The most common adverse event was fatigue and muscular pain. Radiologic response was estimated to occur in 66–100% of the patients. A significant reduction in pain under denosumab treatment was reported in seven studies and additional improvement in function and mobility was reported by several authors. Only two studies reported musculoskeletal tumor society (MSTS) scores which were better after denosumab treatment.The use of denosumab as an adjuvant treatment of GCTB has shown a positive but variable histological response with consistent radiological changes and several types of adverse effects. There is a positive clinical response in terms of pain relief with decrease on the morbidity of surgical procedures to be performed. Finally, oncological outcomes are disparate with neither effect on metastatic disease nor local recurrence rates.IV

Biocompatibility of a Marine Collagen-Based Scaffold In Vitro and In Vivo

Scaffold material is essential in providing mechanical support to tissue, allowing stem cells to improve their function in the healing and repair of trauma sites and tissue regeneration. The scaffold aids cell organization in the damaged tissue. It serves and allows bio mimicking the mechanical and biological properties of the target tissue and facilitates cell proliferation and differentiation at the regeneration site. In this study, the developed and assayed bio-composite made of unique collagen fibers and alginate hydrogel supports the function of cells around the implanted material. We used an in vivo rat model to study the scaffold effects when transplanted subcutaneously and as an augment for tendon repair. Animals&rsquo; well-being was measured by their weight and daily activity post scaffold transplantation during their recovery. At the end of the experiment, the bio-composite was histologically examined, and the surrounding tissues around the implant were evaluated for inflammation reaction and scarring tissue. In the histology, the formation of granulation tissue and fibroblasts that were part of the inclusion process of the implanted material were noted. At the transplanted sites, inflammatory cells, such as plasma cells, macrophages, and giant cells, were also observed as expected at this time point post transplantation. This study demonstrated not only the collagen-alginate device biocompatibility, with no cytotoxic effects on the analyzed rats, but also that the 3D structure enables cell migration and new blood vessel formation needed for tissue repair. Overall, the results of the current study proved for the first time that the implantable scaffold for long-term confirms the well-being of these rats and is correspondence to biocompatibility ISO standards and can be further developed for medical devices application

The effect of patient body mass index and sex on the magnification factor during pre-operative templating for total hip arthroplasty

Introduction: Pre-operative templating prior to hip arthroplasty has traditionally used implant-company-provided acetates, which assumed a magnification factor between 115% and 120%. In recent years, pre-operative planning has been performed with digital calibration devices, in order to calculate the magnification factor. However, these devices are not without their limitations and are not readily available at many institutions. As previous reports suggest a wide range of magnification factors, the determination of an optimal magnification factor is currently unclear. We investigated the relationship between obesity and gender on the magnification factor in order to improve the accuracy of pre-operative templating. Patients and methods: Ninety-seven consecutive pre-operative calibrated pelvic radiographs using the KingMark calibration were analyzed using the TraumaCad templating software. The magnification factor calculated by the software was considered the true magnification factor and analysis was made in order to assess the effect of sex and body mass index (BMI) on the magnification factor. A linear regression analysis was utilized to create a predictive model for optimal magnification factor value. Results: Magnification factor was significantly affected by sex (male, 120.0% vs. female 121.2%, p < 0.01) and by categorized BMI (obese 121.8% vs. non-obese 119.9%, p < 0.001). A positive linear association was found between BMI and the magnification factor (r = 0.544). The magnification factor was significantly different between the following sub-groups: obese female, non-obese female, obese male, and non-obese male (p < 0.001). When applying the model formulated by the linear regression analysis, the calculated magnification factor was within 2% of the true magnification factor for the majority of patients (n = 83, 85.6%). Conclusions: BMI and gender have a significant effect on the magnification factor. Future determination of the magnification factor should consider the influence of these variables in order to improve the accuracy of pre-operative templating in THA