Acute Care Utilization and Costs Up to 4 Years After Index Sleeve Gastrectomy or Roux-en-Y Gastric Bypass: A National Claims-based Study.

OBJECTIVE: To compare acute care utilization and costs following sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB). SUMMARY BACKGROUND DATA: Comparing postbariatric emergency department (ED) and inpatient care use patterns could assist with procedure choice and provide insights about complication risk. METHODS: We used a national insurance claims database to identify adults undergoing SG and RYGB between 2008 and 2016. Patients were matched on age, sex, calendar-time, diabetes, and baseline acute care use. We used adjusted Cox proportional hazards to compare acute care utilization and 2-part logistic regression models to compare annual associated costs (odds of any cost, and odds of high costs, defined as ≥80th percentile), between SG and RYGB, overall and within several clinical categories. RESULTS: The matched cohort included 4263 SG and 4520 RYGB patients. Up to 4 years after surgery, SG patients had slightly lower risk of ED visits [adjusted hazard ratio (aHR): 0.90; 95% confidence interval (CI): 0.85,0.96] and inpatient stays (aHR: 0.80; 95% CI: 0.73,0.88), especially for events associated with digestive-system diagnoses (ED aHR: 0.68; 95% CI: 0.62,0.75; inpatient aHR: 0.61; 95% CI: 0.53,0.72). SG patients also had lower odds of high ED and high total acute costs (eg, year-1 acute costs adjusted odds ratio (aOR) 0.77; 95% CI: 0.66,0.90) in early follow-up. However, observed cost differences decreased by years 3 and 4 (eg, year-4 acute care costs aOR 1.10; 95% CI: 0.92,1.31). CONCLUSIONS: SG may have fewer complications requiring emergency care and hospitalization, especially as related to digestive system disease. However, any acute care cost advantages of SG may wane over time.

Impact on Cardiovascular Health of Using Phentermine/Topiramate in Combination With Laparoscopic Sleeve Gastrectomy in Super Obesity.

INTRODUCTION: Management of patients with BMI≥50 kg/m2 is challenging. In previous work, pre and postoperative pharmacotherapy with phentermine/topiramate plus laparoscopic sleeve gastrectomy (PT + SG) promoted greater weight loss than sleeve gastrectomy (SG) alone at 24 mo postoperatively. This current secondary analysis studied the impact of PT + SG on blood pressure (BP), heart rate, and antihypertensive usage. METHODS: Patients with BMI≥50 kg/m2 planning to have SG (n = 13) were recruited from 2014 to 2016, at an academic medical center in Winston-Salem, North Carolina, for this open-label trial. Participants took phentermine/topiramate (PT; 7.5/46-15/92 mg/d) for ≥3 mo preoperatively and 24 mo postoperatively. The control group (n = 40) underwent SG during the same time frame. We used mixed models for BP and heart rate to compare PT + SG versus SG alone over time, adjusted for age, sex, and initial BP. RESULTS: By 24 mo postoperatively the model adjusted changes in systolic blood pressure/diastolic blood pressure (SBP/DBP) (mm Hg) were -24.44 (-34.46,-14.43)/-28.60 (-40.74,-16.46) in the PT + SG group versus -11.81 (-17.58,-6.05)/-13.89 (-21.32,-6.46) in the control group (SBP P = 0.02; DBP P = 0.03). At baseline 8 (61.5%) participants in the PT + SG arm and 22 (55.0%) in the control group used antihypertensives. Excluding patients lost to follow-up (n = 3), by 24 mo postoperatively, none of the PT + SG participants were on antihypertensives compared to 14 (41.2%) in the control group (P = 0.01). CONCLUSIONS: Patients with BMI≥50 kg/m2 treated with PT + SG had greater improvement in BP with no use of antihypertensive medication at 24 mo postoperatively versus SG alone, where 41% continued medication use. Larger trials are required to evaluate this.

Cyclometallated Palladium(II) Complexes: An Approach to the First Dinuclear Bis(iminophosphorane)phosphane-[C,N,S] Metallacycle.

Treatment of bis(iminophosphorane)phosphane ligands 2a-2e with Li2PdCl4 gave a set of novel diphosphane-derived complexes bearing two metallacycle rings, each one enclosing a P=N double bond: the unprecedented bis(iminophosphorane)phosphane-[C,N,S] palladacycles. In the case of the ligand derived from bis(diphenylphosphino)methane, 2a, both the single and the double palladacycle complexes were obtained. Reaction of 3a with bis(diphenylphosphino)ethane did not yield the expected product with the diphosphane bonded to both palladium atoms, but rather the novel coordination compound 5. The crystal structures of 3c and 5 are described.

Comparative Effectiveness of Vertical Sleeve Gastrectomy Versus Roux-en-Y Gastric Bypass for Diabetes Treatment: A Claims-based Cohort Study.

OBJECTIVE: The aim of the study was to compare diabetes outcomes following vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB). BACKGROUND: There are few comparative studies on diabetes outcomes after VSG and RYGB. METHODS: We used a US-wide commercial insurance claims database to identify adults with diabetes undergoing VSG or RYGB in 2010 to 2016. We matched patients on baseline insulin use, total diabetes medication burden, age, presence of diabetes complications, and follow-up duration, and used adjusted Cox proportional hazards models to compare diabetes medication discontinuation between procedures. We used difference-in-differences analyses to compare changes in medication use intensity up to 2 years after surgery. RESULTS: The matched cohort included 1111 VSG and 922 RYGB patients: 16% were younger than 40 years, 11% were 60 years or older, 67% were women, 67% had a body mass index of 40 kg/m2 or higher, and 23% were on insulin at the time of surgery. Thirteen percent were lost to follow-up at 1 year, and 30% at 2 years after surgery. Patients with VSG were less likely than matched RYGB patients to discontinue all diabetes medications (hazard ratio 0.80, 95% confidence interval 0.72-0.88). Although both groups had substantial decreases in medication use after surgery, RYGB patients had an 86% (32%, 140%) lower total diabetes medication dose than VSG by the second half of postoperative year 2. CONCLUSIONS: In a large claims-based, nationwide cohort of bariatric patients with diabetes, those undergoing RYGB were more likely to come off all medications than those undergoing VSG. Patients with diabetes should consider this potential benefit of RYGB when making informed decisions about obesity treatments.

Flapless immediate implant placement and provisionalization in periodontal patients: A retrospective consecutive case-series study of single-tooth sites with dehiscence-type osseous defects.

OBJECTIVE: To assess the clinical outcomes of flapless, immediate implant placement with simultaneous augmentation of dehiscence defects and immediate provisional restoration. MATERIALS AND METHODS: Retrospective evaluation of 40 periodontal patients who received a flapless immediate implant for single-tooth replacement with simultaneous augmentation of dehiscence defects and immediate provisional restoration, at follow-up periods ranging from 1 year minimum to 7 years maximum. Dehiscence defects were augmented using autogenous bone grafts and/or deproteinized bovine bone mineral, and autogenous or allogeneic connective tissue grafts. The following aspects were evaluated: clinical success (Clinical Oral Implants Research, 8, 1997, 161), crestal bone loss (calibrated digital periapical X-rays) and aesthetics (Pink Esthetic Score, PES). Additionally, a questionnaire was devised to obtain patient's subjective evaluation. RESULTS: A 98.3% (95% CI: 91%-99%) success rate was observed. At 8 weeks, mean bone loss was 0.47 mm (n = 39); between 8 weeks and 1 year, this va lue attained 0.24 mm and between years 1 and 5 years 0.06 mm (n = 9). The evaluated PES in 37 single-tooth implants was 12.4, with PES = 7 (aesthetic failures) in two cases, and aesthetic outcomes were excellent (PES ≥ 12) in 29 cases (78.4%). When compared with the contralateral tooth, a recession under 1 mm was observed in 78% of cases. The patient's subjective satisfaction value ranged from 98% to 100%. CONCLUSION: This type of minimally invasive treatment of alveoli with buccal plate deficiencies delivers, in the hands of an experienced clinician, a high clinical and aesthetic success percentage being rated by patients as satisfactory. Clinicians should be aware that 1-2 mm comparative recession could be observed.

Refractory Gastroparesis Following Duodenal Switch Treated With Laparoscopic Subtotal Gastrectomy With Roux-en-Y Reconstruction.

Gastroparesis following duodenal switch (DS) is a known but rare complication. Typically, patients are managed with prokinetic agents, with pyloromyotomy being the first-line surgical therapy. The literature is sparse regarding how to manage patients whose symptoms remain refractory to these first-line therapies. We present a patient who experienced gastroparesis following DS, who fell into this category. Her symptoms of prandial pain and regurgitation remained resistant to medical management and pyloromyotomy. She was successfully treated with subtotal gastrectomy with Roux-en-Y reconstruction with resolution of these symptoms. The literature suggests that bypassing or resecting the pylorus and removing overstretched aperistaltic gastric muscle could be the mechanism behind this treatment's effectiveness.

Comparison of health care costs following sleeve gastrectomy versus Roux-en-Y gastric bypass among patients with type 2 diabetes.

OBJECTIVE: The objective of this study was to compare the impact of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) on overall and diabetes-specific health care costs among patients with type 2 diabetes. METHODS: This retrospective cohort study examined patients with type 2 diabetes after SG and RYGB using data from Optum's deidentified Clinformatics® Data Mart database. The matched study group included 9608 patients who underwent SG or RYGB and were enrolled between 2007 and 2019. The primary outcomes assessed were overall and diabetes-specific health care costs. RESULTS: Health care costs associated with type 2 diabetes declined substantially in the first few years following both SG and RYGB. RYGB was associated with a larger decrease in pharmacy costs, as well as type 2 diabetes-specific office and laboratory costs. SG was associated with lower total health care costs in the first three follow-up periods and lower acute care costs in the first 2 years after surgery. CONCLUSIONS: In this nationwide study, patients with type 2 diabetes at baseline undergoing RYGB appear to experience a reduced need for ambulatory type 2 diabetes monitoring and reduced requirements for antidiabetes medication but, despite this, did not experience an overall medical cost-benefit in the first few years after RYGB versus SG.

Enhancement of Li/S Battery Performance by a Modified Reduced Graphene Oxide Carbon Host Decorated with MoO3.

Electrochemical energy storage systems based on sulfur and lithium can theoretically deliver high energy with the further benefit of low cost. However, the working mechanism of this device involves the dissolution of sulfur to high-molecular weight lithium polysulfides (LiPs with general formula Li2Sn, n≥4) in the electrolyte during the discharge process. Therefore, the resulting migration of partially dissociated LiPs by diffusion or under the effect of the electric field to the lithium anode, activates an internal shuttle mechanism, reduces the active material and in general leads to loss of performance and cycling stability. These drawbacks poses challenges to the commercialization of Li/S cells in the short term. In this study, we report on the decoration of reduced graphene oxide with MoO3 particles to enhance interactions with LiPs and retain sulfur at the cathode side. The combination of experiments and density functional theory calculations demonstrated improvements in binding interactions between the cathode and sulfur species, enhancing the cycling stability of the Li/S cells.

Outcompeting GC for the detection of legacy chlorinated pesticides: online-SPE UPLC APCI/MSMS detection of endosulfans at part per trillion levels.

Endosulfan, the last remaining organochlorine pesticide, has been the subject of a number of international regulations and restriction/banning action plans worldwide. Occurrence of endosulfan residues in South Florida environments has been widely described in the literature for more than two decades. This work describes a selective, sensitive, and fast online solid-phase extraction (SPE) method coupled with liquid chromatography separation and tandem mass spectrometry (LC-MS/MS) for the determination of endosulfan isomers and endosulfan sulfate in water samples at low part per trillion levels with very little sample preparation. A negative atmospheric pressure chemical ionization source was carefully optimized to produce reproducible spectra of the target compounds with no adduct ion formation. Selected reaction monitoring transitions were monitored and quantitation was performed against a per-deuterated internal standard ß-endosulfan (d4). The automated online SPE clean-up was performed using only 20 mL of untreated water sample prior to LC-MS/MS analysis. The method was capable of separating and quantifying endosulfan within a 24-min run using acetonitrile and water as mobile phases and presenting statistically calculated method detection limits of 3, 10, and 7 ng/L for endosulfan sulfate, α-endosulfan, and ß-endosulfan, respectively. In addition, a QuEChERS method was successfully developed and applied for endosulfan determination in sediments/soils, floating and submerged algal mats, and small fish. Minimal matrix effects were observed in all matrices analyzed and recoveries for all analytes ranged from 50-144 %. The developed methodology was applied to monitor the occurrence and to assess the potential transport of endosulfan in the Loveland Slough watershed, an area adjacent to Everglades National Park showing long-term contamination with endosulfans.

Concentration of trace metals in sediments and soils from protected lands in south Florida: background levels and risk evaluation.

A comprehensive environmental evaluation was completed on 20 metals: two reference metals (Fe, Al) and several minor trace metals (As, Ba, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn) for surface soils and sediments collected from 50 sites in Everglades National Park (ENP), the coastal fringes of Biscayne National Park (BNP), and Big Cypress National Preserve. Samples were prepared by acid digestion (EPA3050) and analyzed by ICP/MS detection (EPA6020). Although no widespread contamination was detected across the two parks and one preserve, there were some specific areas where metal concentrations exceeded Florida's ecological thresholds, suggesting that some metals were of concern. A screening-level evaluation based on a proposed effect index grouped trace metals by their potential for causing negligible, possible, and probable effects on the biota. For example, Cu in BNP and Cr and Pb in ENP were considered of concern because their adverse effect likelihood to biota was assessed as probable; consequently, these trace metals were selected for further risk characterization. Also, stations were ranked based on a proposed overall contamination index that showed that: site BB10 in BNP and sites E3 and E5 in ENP had the highest scores. The first site was located in a marina in BNP, and the other two sites were along the eastern boundary of ENP adjacent to current or former agricultural lands. An assessment tool for south Florida protected lands was developed for evaluating impacts from on-going Everglades restoration projects and to assist State and Federal agencies with resource management. The tool consists of enrichment plots and statistically derived background concentrations based on soil/sediment data collected from the two national parks and one preserve. Finally, an equally accurate but much simplified approach is offered for developing enrichment plots for other environmental settings.

Endoscopic Ultrasound-Guided Gastro-gastrostomy Using Lumen Apposing Metal Stent for Management of High-Grade Gastric Outlet Obstruction Secondary to Vertical Banded Gastroplasty.

Vertical banded gastroplasty (VBG) is associated with an increased risk of pouch stricture secondary to narrowing of the banded gastroplasty outlet. We describe a case of a 60-year-old male with stage 4 small cell lung cancer presenting with recurrent gastric outlet obstruction secondary to stenosis at the site of VBG. Given a prior history of failed standard endoscopic maneuvers including balloon dilation and steroid injection, the decision was made to create an endoscopic ultrasound-guided gastro-gastrostomy using lumen opposing metal stent. The patient did well post procedure and was able to tolerate a soft mechanical diet within 24 h. He was subsequently discharged to hospice for his advanced metastatic disease.

Strategies to reduce the onset of sleeve gastrectomy associated bone loss (STRONG BONES): Trial design and methods.

Background: Despite recognized improvements in obesity-related comorbidities, mounting evidence implicates surgical weight loss in the onset of skeletal fragility. Sleeve gastrectomy (SG) is the most commonly performed bariatric procedure and is associated with 3-7% axial bone loss in the year following surgery. Bisphosphonates are FDA-approved medications for the prevention and treatment of age-related bone loss and may represent a strategy to reduce bone loss following SG surgery. Methods: The Strategies to Reduce the Onset of Sleeve Gastrectomy Associated Bone Loss (STRONG BONES) trial (NCT04922333) is designed to definitively test whether monthly administration of the bisphosphonate, risedronate, for six months can effectively counter SG-associated bone loss. Approximately 120 middle-aged and older (≥40 years) SG patients will be randomized to six months of risedronate or placebo treatment, with skeletal outcomes assessed at baseline, six, and 12-months post-surgery. The primary outcome of the trial is 12-month change in total hip areal bone mineral density (aBMD), measured by dual energy x-ray absorptiometry (DXA). This will be complemented by DXA-acquired aBMD assessment at other skeletal sites and quantitative computed tomography (QCT) derived changes in bone quality. Change in muscle mass and function will also be assessed, as well as biomarkers of bone health, turnover, and crosstalk, providing mechanistic insight into intervention-related changes to the bone-muscle unit. Discussion: Results from the STRONG BONES trial have the potential to influence current clinical practice by determining the ability of bisphosphonate use to mitigate bone loss and concomitant fracture risk in middle-aged and older SG patients.

Ceramic/metal biocidal nanocomposites for bone-related applications.

Hydroxyapatite/silver nanocomposites have been designed and synthesized as an engineering material for biomedical applications. The hydroxyapatite matrix was synthesized by a sol-gel method and, subsequently, the Ag nanoparticles were deposited by heterogeneous precipitation followed by two different reduction routes: thermal or chemical. Both sets were studied and compared and, in all cases, the metal nanoparticles appear perfectly isolated and attached to the surface of the hydroxyapatite. The average metal particle size is below 10 nm, allowing an important contact surface between silver and the microorganisms. The antimicrobial behavior against common bacteria showed a high effectiveness, well above the commercial level, as well as against yeast, in the case of the chemically reduced sample. Due to the nanocomposite microstructure, only a negligible portion of metal was released to the lixiviated liquid after the biocide tests, minimizing the risk of toxicity. These nanocomposites offer a solution to the infections on the surface of implants, one of the main problems in reaching a suitable level of osseointegration.

Lithium aluminosilicate reinforced with carbon nanofiber and alumina for controlled-thermal-expansion materials.

Materials with a very low or tailored thermal expansion have many applications ranging from cookware to the aerospace industry. Among others, lithium aluminosilicates (LAS) are the most studied family with low and negative thermal expansion coefficients. However, LAS materials are electrical insulators and have poor mechanical properties. Nanocomposites using LAS as a matrix are promising in many applications where special properties are achieved by the addition of one or two more phases. The main scope of this work is to study the sinterability of carbon nanofiber (CNFs)/LAS and CNFs/alumina/LAS nanocomposites, and to adjust the ratio among components for obtaining a near-zero or tailored thermal expansion. Spark plasma sintering of nanocomposites, consisting of commercial CNFs and alumina powders and an ad hoc synthesized ß-eucryptite phase, is proposed as a solution to improving mechanical and electrical properties compared with the LAS ceramics obtained under the same conditions. X-ray diffraction results on phase compositions and microstructure are discussed together with dilatometry data obtained in a wide temperature range (-150 to 450 °C). The use of a ceramic LAS phase makes it possible to design a nanocomposite with a very low or tailored thermal expansion coefficient and exceptional electrical and mechanical properties.

3D photogrammetry as a tool for studying erosive processes at a Roman coastal site: the case of the Roman fish-salting plant at Sobreira (Vigo, Spain).

Rising sea levels, along with other biological and human factors, have increased erosion rates at a number of important sites located along the Atlantic coastline. Project GaltFish implemented a series of contingency measures to record some of these sites before they degraded further or totally disappeared. This process involved detailed photogrammetric recording of some of the sites under threat over a set period of time. One of the sites selected for this project was Sobreira (Vigo, Galicia): a Roman fish-salting factory which was partially destroyed by building activity in the 1980s and the remains of which are under threat from marine erosion and human action. In order to study the site, two photogrammetric models were created to examine the effect of erosive processes across the course of one year. The results illustrate that photogrammetry is an efficient tool for recording and analysing the issue of erosion. The data compiled helped in designing additional action in the factory, which was subject to a rescue excavation to record and help protect the site from further damage. This paper presents the results of this project, as well as the methodology used to produce the models, the data generated and their analysis. It is argued that the methodology can be used to collect and analyse data from other sites, and that this data could inform the political/administrative decision-making processes which concern the future management and preservation of archaeological sites under threat.

Comparison of Ambulatory Health Care Costs and Use Associated With Roux-en-Y Gastric Bypass vs Sleeve Gastrectomy.

Importance: Studies comparing contemporary bariatric surgical types could facilitate procedure selection for patients interested in reducing their frequency of health care visits and reliance on prescription drugs. Objective: To compare the association of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) with ambulatory health care costs and use for as long as 4 years after surgery. Design, Setting, and Participants: This comparative effectiveness study, which included patients undergoing bariatric surgery who were aged 18 to 64 years with at least 24 months of enrollment data before surgery and 12 months of enrollment data after surgery, used a retrospective interrupted time series with a comparison group. Data represent insurance claims dated January 2006 to June 2017, with analyses completed in September 2021. Data were collected from US commercial and Medicare Advantage claims database. Cohorts were matched on characteristics including baseline body mass index category, diabetes status, baseline ambulatory care costs, region of the United States, and year of surgery. Exposures: SG or RYGB, based on procedure codes. Main Outcomes and Measures: Annual ambulatory health care costs, and subtypes of cost and use including prescriptions, office visits, laboratory encounters, and radiology. Results: Matched cohorts included 3049 patients who underwent SG and 3251 patients who underwent RYGB, with a mean (SD) age of 45.2 (10.0) years; 4820 (77%) were women. Full follow-up was 37% for SG (514 patients) and 38% for RYGB (643 patients) among those eligible for 4-year follow-up. There were no significant differences between SG and RYGB in total ambulatory costs, office visit costs, or radiology costs in all follow-up years. Patients who underwent SG had significantly higher prescription costs than those who underwent RYGB bypass in year 4 ($852.8 per patient per year; 95% CI: $395.6-$1310.0 per patient per year) with more cardiometabolic medication fills in each year (eg, year 4: 42.5%; 95% CI, 13.7%-71.2%). In contrast, early after surgery, patients who underwent SG had relatively fewer specialist visits (eg, year 1: -7.2%; 95% CI, -14.3% to -0.2%) and lower laboratory costs (eg, year 1: -$118.9 per patient per year; 95% CI, -$220.2 to -$17.5 per patient per year). Conclusions and Relevance: Despite clinical studies showing greater weight loss and comorbidity improvement with RYGB vs SG, this study found no difference in total ambulatory costs for as long as 4 years after SG and RYGB. These findings may reflect the trade-off between greater improvements in cardiometabolic health and additional surgery-related care among patients undergoing RYGB. Studies with longer follow-up time could determine whether greater sustained weight loss from RYGB eventually results in lower costs compared with SG.

Outcomes After Laparoscopic Cholecystectomy in Hyperkinetic Biliary Dyskinesia.

BACKGROUND: Biliary dyskinesia (BD) is a poorly understood functional gallbladder disorder. Diagnosis is made with abdominal pain and an intact gallbladder without signs of anatomical obstruction on imaging or pathology. Our aim was to assess whether laparoscopic cholecystectomy (LC) resolves hyperkinetic BD symptoms. METHODS: Records of patients ≥18 years of age, who underwent LC by four surgeons at a tertiary care center between 2012 and 2020, were retrospectively reviewed. Patients were excluded if they had a documented gallbladder ejection fraction (GBEF) <80% or had biliary stones or sludge on pathology or imaging. Demographic information, HIDA results, preoperative testing, operative details, gallbladder pathology, and symptom status at follow-up were collected from electronic medical records. Improvement in BD symptoms was assessed using McNemar's test. Risk differences with standard errors were employed to estimate percent reduction in symptoms. RESULTS: Ninety-eight patients met inclusion criteria. Of those who presented for follow-up (n = 91), 92.3% (n = 84) reported partial or complete resolution of symptoms. Preoperative symptoms, including back pain (16.7%, 95% CI: [7.9%, 25.5%]; P < .0001), epigastric pain (31.1% [21.3%, 41.3%]; P < .0001), nausea (56.7% [45.0%, 65.8%]; P < .0001), RUQ pain (57.8% [46.1%, 66.9%]; P < .0001), and vomiting (27.8% [18.4%, 37.7%]; P < .0001) showed significant improvement after LC. Chronic cholecystitis and/or cholesterolosis were present on pathology in 79.8% of gallbladders. DISCUSSION: Our study currently represents the largest cohort of patients with hyperkinetic BD. Laparoscopic cholecystectomy appears to result in resolution of symptoms for this clinical entity.

Non-contrasted computed tomography for the accurate measurement of liver steatosis in obese patients.

BACKGROUND: Hepatic macrosteatosis (HMS) is prevalent among high BMI patients, but a lack of validation of non-invasive measures of liver fat hampers non-alcoholic liver disease (NAFLD) investigation in general. Recent work suggests BMI adjusted, non-contrasted computed tomography (nc-CT) attenuation data (Hounsfield units) reflects liver fat accumulation in a normal weight population. However, this and other CT-based HMS studies have only approximated macrosteatosis (%) histologically, but have not validated findings with chemical liver triglyceride (TG) concentrations (mg/gram protein). Also, all previous CT based steatosis studies excluded high BMI subjects, whose habitus may affect properties of the scan. We hypothesized that in high BMI patients nc-CT attenuation measurements expressed in Hounsfield units (HU) accurately estimate liver triglyceride concentrations as well as histological macrosteatosis. METHODS: With informed consent, 15 patients underwent nc-CT scan of the abdomen prior to weight loss surgery with intraoperative wedge and core needle liver biopsy. Mean left lobe nc-CT Hounsfield units (CT(L)), liver TG (mg/g Pr), HMS (%), BMI (kg/m(2)), liver-spleen index (CT(L/S) = hepatic HU/splenic HU), and liver-spleen difference (CT(L-S) = hepatic HU - splenic HU) were a priori outcomes. RESULTS: In 15 patients (11 female) with a BMI of 44.4 ± 1.1 (mean ± SEM), CT(L/S), CT(L-S), and CT(L) measures were significantly associated with liver TG concentrations (r = -0.80, P < 0.001; r = -0.80, P < 0.001; and r = -0.71, P < 0.01, respectively; Table 1). Macrosteatosis (%) and liver triglyceride concentration were positively associated (r = 0.83; P < 0.0001). BMI did not correlate strongly to liver triglyceride (r = 0.44, P = NS). CONCLUSION: Estimates of liver fat obtained by nc- CT scans (esp. CT(L/S), CT(L-S)) correlate to chemical measurement of liver triglyceride concentrations, suggesting non-contrasted CT may be a suitable non-invasive "gold standard" for hepatic steatosis quantification in these patients.

Whey-Derived Porous Carbon Scaffolds for Bone Tissue Engineering.

Porous carbon structures derived from whey powders are described and evaluated as potential scaffolds in bone tissue engineering. These materials have a porosity between 48% and 58%, with a hierarchical pore size distribution ranging from 1 to 400 micrometres. Compressive strength and elastic modulus are outstanding for such a porous material, being up to three times better than those of traditional HA or TCP scaffolds with similar porosities. They also present non-cytotoxic and bioactive behavior, due to their carbon-based composition that also includes some residual mineral salts content.