Factors associated with improved survival among young adult melanoma patients despite a greater incidence of sentinel lymph node metastasis

INTRODUCTION: We sought to evaluate the factors that affect sentinel lymph node (SLN) metastasis and survival among young melanoma patients (< or =30 y). METHODS: The Sunbelt Melanoma Trial is a multi-institutional prospective randomized trial of patients aged 18 to 70 y. Statistical analyses were performed to determine if patients < or =30 y of age had a significantly different outcome in terms of SLN metastasis, disease-free survival (DFS), and overall survival (OS) compared to older patients. RESULTS: The median age of the 3031 patients in this study was 50 y (range 18 to 77 y); the 315 patients (10.4%) < or =30 y old were compared with those >30 y old. Of the 1944 patients with follow-up, the median follow-up was 48 mo. On univariate analysis, younger patients were more often female (54.7% versus 40.9%, P < 0.0005), with tumors <4 mm thick (94.9% versus 89.4%, P = 0.001) without ulceration (80.3% versus 70.9%, P < 0.0005) or evidence of regression (93.8% versus 87.8%, P = 0.003), and were less likely to have lentigo maligna (0.0% versus 2.6%) or acral lentiginous (0.4% versus 3.1%, P < 0.0005) subtype. Patient age < or =30 was associated with SLN metastasis on univariate (24.6% versus 19.7%, P = 0.05) and multivariate (OR = 1.77, 95% CI = 1.26-2.49, P = 0.001) analyses. With a median follow-up of 48 mo, younger patients had a significantly improved 5-y DFS (86.2% versus 79.1%, P = 0.036) and OS (89.9% versus 80.1%, P = 0.010). On multivariable Cox regression analysis, however, age group was not a significant independent prognostic factor affecting DFS or OS. CONCLUSION: Despite a higher rate of SLN metastasis, patients < or =30 y old do not have a worse survival attributable to a more favorable clinicopathologic profile.     

A method for dry extracting large volumes of fine particulate matter from bulk soil samples

A significant part of ambient dust consists of fine particles derived from natural soils. Because many toxic constituents are concentrated in the smallest particle fractions, and because these small particulates are the most easily inhaled, the fine-particle fraction of soil (PM10 and smaller) is what presents the greatest health concern. Assessing the potential risk of a soil requires examining its chemical content, its biological and mineralogical composition, its sedimentological characteristics, detailed data on grain size distribution, and other information. This analysis requires a relatively large mass of appropriate size fraction(s), obtained by dry extraction. Most methods for extracting fine particulates from soil collect only small amounts of sediment, or use wet extraction. This paper describes the Soil Fine Particle Extractor, a setup for dry extracting large volumes (dozens of grams and more) of fine particulate matter (PM10 and smaller) from bulk soil samples. Separation takes place in two steps. Primary separation in a cylindrical separator 70?cm high and 40?cm in diameter removes all coarse particles from the sample. The remaining sediment then flows through a 200?cm long and 7?cm diameter inclined elutriator connected to a three-engine vacuum cleaner. The setup allows extraction of different size fractions depending on the adjustment of the control parameters (suction rate, length, diameter and inclination of the elutriator, thickness of the sediment layer drawn in by the system). The article presents examples of extractions from soil collected in loess and desert environments, ranging from PM2.5 to PM10. It also evaluates the efficiency of the technique by investigating the extraction efficiency for a large number of particle sizes, varying from 0.1 to 70???m. Extraction occurs most efficiently for particles between 1 and 10???m, with an optimum around 5???m.     

Rinderpest Virus Sequestration and Use in Posteradication Era

After the 2011 declaration of rinderpest disease eradication, we surveyed 150 countries about rinderpest virus stocks. Forty-four laboratories in 35 countries held laboratory-attenuated strains, field strains, or diagnostic samples. Vaccine and reagent production and laboratory experiments continued. Rigorous standards are necessary to ensure that stocks are kept under safe conditions.     

Immunoglobulin free light chains and solitary plasmacytoma of bone

An abnormal serum immunoglobulin free light chain (FLC) ratio at diagnosis may identify risk of progression to myeloma in patients with solitary bone plasmacytoma (SBP). In the cohort of 116 patients, 43 have progressed to myeloma, with a median time to progression of 1.8 years. The FLC ratio was determined in all 116 patients on serum collected at time of diagnosis and was abnormal in 54 patients (47%). An abnormal FLC ratio was associated with a higher risk of progression to myeloma (P = .039). The risk of progression at 5 years was 44% in patients with an abnormal serum FLC ratio at diagnosis compared with 26% in those with a normal FLC ratio. One to 2 years following diagnosis, a persistent serum M protein level of 5 g/L (0.5 g/dL) or higher was an additional risk factor for progression. A risk stratification model was constructed using the 2 variables of FLC ratio and M protein level: patients with a normal FLC ratio at baseline and M protein level less than 5 g/L (0.5 g/dL) at 1 to 2 years following diagnosis (low risk, n = 31); with either risk factor abnormal (intermediate risk, n = 26); and with both an abnormal FLC ratio and M protein level of 5 g/L (0.5 g/dL) or higher (high risk, n = 18). The corresponding progression rates at 5 years were significantly different in the low, intermediate, and high groups: 13%, 26%, and 62%, respectively (P < .001).     

Similar risk of complete revision for infection with single-dose versus multiple-dose antibiotic prophylaxis in primary arthroplasty of the hip and knee: results of an observational cohort study in the Dutch Arthroplasty Register in 242,179 patients

Background and purpose — The optimal type and duration of antibiotic prophylaxis for primary arthroplasty of the hip and knee are subject to debate. We compared the risk of complete revision (obtained by a 1- or 2-stage procedure) for periprosthetic joint infection (PJI) after primary total hip or knee arthroplasty between patients receiving a single dose of prophylactic antibiotics and patients receiving multiple doses of antibiotics for prevention of PJI.Patients and methods — A cohort of 130,712 primary total hip and 111,467 knee arthroplasties performed between 2011 and 2015 in the Netherlands was analyzed. We linked data from the Dutch arthroplasty register to a survey collected across all Dutch institutions on hospital-level antibiotic prophylaxis policy. We used restricted cubic spline Poisson models adjusted for hospital clustering to compare the risk of revision for infection according to type and duration of antibiotic prophylaxis received.Results — For total hip arthroplasties, the rates of revision for infection were 31/10,000 person-years (95% CI 28–35), 39 (25–59), and 23 (15–34) in the groups that received multiple doses of cefazolin, multiple doses of cefuroxime, and a single dose of cefazolin, respectively. The rates for knee arthroplasties were 27/10,000 person-years (95% CI 24–31), 40 (24–62), and 24 (16–36). Similar risk of complete revision for infection among antibiotic prophylaxis regimens was found when adjusting for confounders.Interpretation — In a large observational cohort we found no apparent association between the type or duration of antibiotic prophylaxis and the risk of complete revision for infection. This does question whether there is any advantage to the use of prolonged antibiotic prophylaxis beyond a single dose.

Annually around 1 million patients receive a total hip or total knee prosthesis in the United States and over 190,000 hip and knee replacements are performed in England and Wales (Maradit et al. 2015, National Joint Registry for England and Wales 2018). The incidences of prosthetic replacement of the hip and knee are expected to increase (Kurtz et al. 2014). Prosthetic joint infection (PJI) following total hip or knee arthroplasty and the treatment thereof are catastrophic for patients and pose tremendous costs to healthcare systems (Poultsides et al. 2010, Zmistowski et al. 2013, Moore et al. 2015). Perioperative antibiotic prophylaxis remains an effective method of reducing the risk of PJI (Illingworth et al. 2013, Thornley et al. 2015). The type and duration of antibiotic prophylaxis are subject to debate.Both single-dose and multiple-dose antibiotic prophylaxis regimens have been advocated with comparable results (Thornley et al. 2015, Tan et al. 2019). The recommendations provided by the Second International Consensus Meeting of the MusculoSkeletal Infection Society (MSIS) and the European Bone and Joint Infection Society (EBJIS) advise that antibiotic prophylaxis should be administered 30–60 minutes before incision and discontinued within 24 hours after surgery (Hansen et al. 2014, Parvizi and Gehrke 2018). Large variation in prophylaxis regimens has been observed in the United Kingdom (Hickson et al. 2015). The Dutch national orthopedic association advises administration of antibiotic prophylaxis using a first- or second-generation cephalosporin starting 30–60 minutes preoperatively and discontinuing the antibiotic prophylaxis within 24 hours (Swierstra et al. 2009, Nederlandse Orthopaedische Vereniging 2018). The World Health Organization and, in the USA, the Centers for Disease Control and Prevention (CDC) recommend against the use of postoperative continuation of antibiotic prophylaxis and advocate for a single dose of antibiotics delivered preoperatively (Berrios-Torres et al. 2017). This recommendation is vehemently challenged by the American Association of Hip and Knee Surgeons and the International Consensus Meeting, which encourage their members to proceed with the current common practice of multiple-dose antibiotic prophylaxis protocols until more evidence is available (Yates 2018).We compared the risk of complete revision for infection in the 1st year following primary hip and knee arthroplasty according to the perioperatively administered antibiotic prophylaxis regimen by using data from the Dutch Arthroplasty Register (LROI).