Search

Sphingolipids are a heterogeneous class of lipids and essential components of the plasma membrane and plasma lipoproteins. Studies have shown that plasma deoxysphingolipid (DSL), a newly identified sphingolipid class, is increased in diabetic patients and associated with diabetic neuropathy. However, it remains unknown if there is a causal relationship between plasma DSL increase and diabetic neuropathy. Since matrix metalloproteinases (MMPs) play an important role in diabetic neuropathy by degrading extracellular matrix in the peripheral nervous system, we investigated the effect of DSLs on the expression of MMPs and tissue inhibitor of metalloproteinase (TIMPs), and cytotoxicity in human Schwann cells. We quantified protein secretion, gene expression, and collagenase activity, and performed cytotoxicity assays. Results showed that DSLs upregulated MMP-1, downregulated TIMP-1, and induced cytotoxicity in Schwann cells. Furthermore, we quantified DSLs in VLDL, LDL, HDL2, and HDL3 isolated from type 2 diabetes mellitus (T2DM) patients with or without neuropathy. Interestingly, lipidomic analysis showed that only HDL2 isolated from T2DM patients with neuropathy contains significantly higher level of DSLs than that isolated from T2DM patients without neuropathy. Additionally, results showed that HDL2 isolated from T2DM patients with neuropathy was more potent than that isolated from T2DM patients without neuropathy in upregulating MMP-1, downregulating TIMP-1, and stimulating collagenase activity in Schwann cell. Taken together, this study demonstrated for the first time a potential causal relationship between DSLs and diabetic neuropathy and that DSL-containing HDL2 from T2DM patients with neuropathy was more potent than that from T2DM patients without neuropathy in stimulating collagenase activity.

BACKGROUND: To evaluate the comparative abilities of commercially available, viable, cellular bone allografts to promote posterolateral spinal fusion. METHODS: Human allografts containing live cells were implanted in the athymic rat model of posterolateral spine fusion. Three commercially available allogeneic cellular bone matrices (Trinity Evolution, Trinity ELITE and Osteocel Plus) were compared with syngeneic iliac crest bone as the control. All spines underwent radiographs, manual palpation, and micro–computed tomography (CT) analysis after excision at 6 weeks. Histological sections of randomly selected spines were subjected to semiquantitative histopathological scoring for bone formation. RESULTS: By manual palpation, posterolateral fusion was detected in 40% (6/15) of spines implanted with syngeneic bone, whereas spines implanted with Trinity Evolution and Trinity ELITE allografts yielded 71% (10/14) and 77% (10/13) fusion, respectively. Only 7% (1/14) of spines implanted with Osteocel Plus allografts were judged fused by manual palpation (statistically significantly less than ELITE, P < .0007, and Evolution, P < .0013). The mineralized cancellous bone component of the allografts confounded radiographic analysis, but Trinity Evolution (0.452 ± 0.064) and Trinity ELITE (0.536 ± 0.109) allografts produced statistically significantly higher bone fusion mass volumes measured by quantitative micro-CT than did syngeneic bone (0.292 ± 0.109, P < .0001 for ELITE and P < .003 for Evolution) and Osteocel Plus (0.258 ± 0.103, P < .0001). Semiquantitative histopathological scores supported these findings because the total bone and bone marrow scores reflected significantly better new bone and marrow formation in the Trinity groups than in the Osteocel Plus group. CONCLUSIONS: The Trinity Evolution and Trinity ELITE cellular bone allografts were more effective at creating posterolateral fusion than either the Osteocel Plus allografts or syngeneic bone in this animal model. CLINICAL RELEVANCE: The superior fusion rate of Trinity cellular bone allografts may lead to better clinical outcome of spinal fusion surgeries.

Objective This study was conducted to compare therapeutically relevant properties of platelet-rich plasma (PRP), a commonly used autologous intra-articular treatment for osteoarthritis (OA), with those of a novel placental tissue particulate, PTP-001, which is in development as a regulated biologic treatment for knee OA. Design Quantitative immunoassays were performed to determine the content of key growth/regulatory biofactors in PTP-001, and in leukocyte-rich (LR)-PRP or leukocyte-poor (LP)-PRP. An anti-inflammatory bioassay was used to evaluate the effects of each treatment on pro-inflammatory cytokine (tumor necrosis factor (TNF)-α) production in a macrophage cell culture system. Gene expression experiments were conducted using a co-culture system of human synoviocytes (pre-stimulated with interleukin (IL)-1β) and articular chondrocytes, with quantitative polymerase chain reaction analyses of the separate cellular compartments. Results The concentrations of several biofactors (e.g., basic fibroblast growth factor, tissue inhibitor of metalloproteases-3, interleukin-1 receptor antagonist) representative of diverse disease-relevant mechanisms of action were significantly higher for PTP-001 relative to LR-PRP or LP-PRP. PTP-001 and PRP preparations were able to reduce TNF-α production in macrophage cell cultures; however, greater variability was observed for PRP in comparison with PTP-001. In the chondrocyte/synoviocyte co-culture experiments, PTP-001 and LR-PRP (but not LP-PRP) significantly reduced chondrocyte MMP13 expression in cultures containing IL-1-pretreated synoviocytes. In addition, ADAMTS5 expression was reduced in the chondrocyte compartment following treatment with PTP-001 relative to PRP. Conclusion These findings support evidence of a potent, multifactorial mechanism of action for a consistently manufactured biologic (PTP-001), which may be of greater therapeutic benefit in comparison with more heterogeneous preparations of PRP which may be generated at the time of treatment.

Reduced anthelmintic efficacy in beef cattle has recently been documented at the national level. The objective of this study was to determine if anthelmintic resistance is present in Maryland beef cattle herds. For this study, the fecal egg count reduction (FECR) test was used to assess anthelmintic efficacy of composite samples. Between July and October 2020, anthelmintic efficacy was assessed for 17 groups of cattle across 14 individual farms in Maryland. Each test group consisted of 24 ± 6 calves or yearlings (< 16 months of age). Previous anthelmintic treatment history was used to assign each group to one of four commercially available anthelmintics: moxidectin (injectable), moxidectin (pour-on), doramectin, or fenbendazole. Prior to treatment, cattle were weighed to ensure appropriate dose according to the product label. Fecal samples were collected from all cattle within each group before and after (17 ± 5 d) treatment. Pre- and post-treatment samples were composited for each group on an equal-weight basis (10g per animal) and the number of eggs within the sample was determined using the 3-chambered McMaster technique. The mean FECR across all four anthelmintics was 60 ± 19% (mean ± 95% confidence interval), indicating that the anthelmintics tested in this study were largely ineffective. The FECR for the moxidectin injectable, moxidectin pour-on, doramectin, and fenbendazole treatments were 71 ± 38%, 47 ± 46%, 35 ± 88%, and 96 ± 18% (mean ± 95% confidence interval), respectively. Although these data indicate no statistically significant differences for efficacy among the four products tested, they do suggest that efficacy is highly variable across different anthelmintics and farms. Results also indicate that anthelmintic resistance exists on many cattle farms in Maryland. This study provides evidence that supports the need for more judicious anthelmintic use and alternative gastrointestinal parasite control measures in Maryland beef cattle herds.

Energy is often the most limiting nutrient in pasture diets. The effect of energy supplementation on the growth, health, and carcass traits of pasture-raised lambs was investigated. Seventy-nine Katahdin ram lambs were delivered to the Western Maryland Research & Education Center on June 15. After an 11-d acclimation period, lambs were allocated to two treatment groups based on age, weight, birth type, and FEC. Lambs in the PASTURE group (n = 40) rotationally grazed 2 ha of high quality, mixed pasture for 102 d. Lambs in the SUPPL group (n = 39) grazed similar pastures and were hand-fed a daily energy supplement (450 g of whole barley). The groups were handled bi-weekly to determine body weights, FAMACHA©, BCS, and dag scores. Individual fecal samples were collected upon arrival and at two additional time points. Lambs were ultrasound scanned on Sept 25 to determine carcass traits. Data were analyzed using the MIXED procedure of SAS, with statistical significance set at P ≤ 0.05. ADG varied considerably among weigh periods. Standard deviations were typically quite large, indicating wide variation in individual performance. Overall, the SUPPL lambs had higher ADG (P < 0.01), more backfat (P < 0.03), and higher BCS (P < 0.01) than the PASTURE lambs. There were no statistical differences in starting weight, ending weight, and loin depth. While internal parasites were not a problem during the study (only one lamb had a FAMACHA© score >4), PASTURE lambs had lower FEC (P < 0.05) on August 17 (240 ± 81 vs. 468 ± 80 epg). The value of additional gain (0.9 kg) would not have covered the cost of feed; however, four lambs were removed from the PASTURE group (due to death or failure to thrive) whereas only two lambs were removed from the SUPPL group. The study will be repeated in 2021 with similar lambs and protocol.

Introduction Cellular bone matrices (CBM) are allograft products that provide three components essential to new bone formation: an osteoconductive scaffold, extracellular growth factors for cell proliferation and differentiation, and viable cells with osteogenic potential. This is an emerging technology being applied to augment spinal fusion procedures as an alternative to autografts. Methods We aim to compare the ability of six commercially‐available human CBMs (Trinity ELITE®, ViviGen®, Cellentra®, Osteocel® Pro, Bio4® and Map3®) to form a stable spinal fusion using an athymic rat model of posterolateral fusion. Iliac crest bone from syngeneic rats was used as a control to approximate the human gold standard. The allografts were implanted at L4‐5 according to vendor specifications in male athymic rats, with 15 rats in each group. MicroCT scans were performed at 48 hours and 6 weeks post‐implantation. The rats were euthanized 6 weeks after surgery and the lumbar spines were harvested for X‐ray, manual palpation and histology analysis by blinded reviewers. Results By manual palpation, five of 15 rats of the syngeneic bone group were fused at 6 weeks. While Trinity ELITE had eight of 15 and Cellentra 11 of 15 rats with stable fusion, only 2 of 15 of ViviGen‐implanted spines were fused and zero of 15 of the Osteocel Pro, Bio4 and Map3 produced stable fusion. MicroCT analysis indicated that total bone volume increased from day 0 to week 6 for all groups except syngeneic bone group. Trinity ELITE (65%) and Cellentra (73%) had significantly greater bone volume increases over all other implants, which was consistent with the histological analysis. Conclusion Trinity ELITE and Cellentra were significantly better than other implants at forming new bone and achieving spinal fusion in this rat model at week 6. These results suggest that there may be large differences in the ability of different CBMs to elicit a successful fusion in the posterolateral spine., We aim to compare the ability of six commercially‐available human CBMs (Trinity ELITE, ViviGen, Cellentra, Osteocel Pro, Bio4 and Map3) to form a stable spinal fusion using an athymic rat model of posterolateral fusion. Our results showed that Trinity ELITE and Cellentra were significantly better than other implants at forming new bone and achieving spinal fusion in this rat model at week 6.

Sphingolipids are bioactive lipids associated with cellular membranes and plasma lipoproteins, and their synthesis and degradation are tightly regulated. We have previously determined that low plasma concentrations of certain ceramide species predict the development of nephropathy in diabetes patients with normal albumin excretion rates at baseline. Herein, we tested the hypothesis that altering the sphingolipid content of circulating lipoproteins can alter the metabolic and signaling pathways in podocytes, whose dysfunction leads to an impairment of glomerular filtration. Cultured human podocytes were treated with lipoproteins from healthy subjects enriched in vitro with C16 ceramide, or D-erythro 2-hydroxy C16 ceramide, a ceramide naturally found in skin. The RNA-Seq data demonstrated differential expression of genes regulating sphingolipid metabolism, sphingolipid signaling, and mTOR signaling pathways. A multiplex analysis of mTOR signaling pathway intermediates showed that the majority (eight) of the pathway phosphorylated proteins measured (eleven) were significantly downregulated in response to C16 ceramide-enriched HDL2 compared to HDL2 alone and hydroxy ceramide-enriched HDL2. In contrast, C16 ceramide-enriched HDL3 upregulated the phosphorylation of four intermediates in the mTOR pathway. These findings highlight a possible role for lipoprotein-associated sphingolipids in regulating metabolic and signaling pathways in podocytes and could lead to novel therapeutic targets in glomerular kidney diseases.

Gastro-intestinal parasites, especially Haemonchus contortus, limit the profitability and expansion of the meat goat industry in many states. The objective of the Western MD Pasture Based Meat Goat Production test was to evaluate the performance of meat goat bucklings (mostly Kiko and Kiko crosses), consuming a pasture-based diet, with natural exposure to gastro-intestinal parasites. From 2006–2016, the FAMACHA© system was used to determine need for deworming (scores of 4 and 5) in all kids. Therefore, goats were handled bi-weekly to determine body weights (BW), FAMACHA© scores (FAM) and fecal egg counts (FEC) in eggs per gram (epg), as well as other possible indicators of internal parasitism. Adjacent FAMACHA© scores were used to form 3 groups; kids not requiring treatment (FAM1; FAM 1 and 2), kids intermediate (FAM 3) and kids requiring treatment (FAM 5; FAM 4 and 5). Differences in mean log-transformed FEC (LFEC) and ADG were determined using the PROC MIXED procedure of SAS and included year, FAMACHA© score and FAMACHA© score by year interaction effects. There was an exponential increase in LFEC and decrease in ADG with increasing FAM score groups for most years of the test. LFEC were significantly different for FAM1, FAM3, and FAM5 groups (P

A pasture-based meat goat performance test was conducted at the University of Maryland’s Western Maryland Research & Education Center (39º 30’ N/77º 44’ W) from 2007–2016. The purpose of the test was to evaluate the performance of meat goat bucklings (mostly Kiko and Kiko crosses), consuming a pasture-based diet, with natural exposure to gastro-intestinal parasites. While on test, the goats were handled bi-weekly to determine body weights (BW), FAMACHA© scores (FAM) and body condition (BCS) scores. Coat condition (COAT), dag (DAG) and diarrhea scores (DISCO) and deworming frequency (TX) were also recorded from 2012–2016. Fecal samples were collected bi-weekly to determine individual fecal eggs counts (FEC; 2007–2016) and pooled samples were collected every 28 days for larvae ID (2009–2016). Data came from 811 meat goat kids representing 100 herds in 20 states. Residual correlations among log-transformed FEC (LFEC), FAMACHA© scores, BW, ADG, BCS, coat condition, dag and fecal consistency scores were determined. In addition, deworming frequency by year was determined by PROC FREQ in SAS. The predominant genera of gastrointestinal nematode cultured was Haemonchus contortus ranging from 70–95% over the 10-yrs. Overall, residual correlations (r) of FAMACHA scores with ADG (-0.15), LFEC (0.24), BCS (-0.09), COAT (-0.06), DAG (0.12) and DISCO (0.04) were significant (P

Webinars can be an effective teaching tool. In 2011, the MD Small Ruminant Extension Program initiated webinar short courses as a means of educating sheep and goat producers. Ten short courses, consisting of 2–6 webinars each, were held over a 6-year period: 1) Special topics (2016); 2) Pasture management (2015); 3) National Sheep Improvement Program (2015); 4) Health (2014); 5) Ethnic marketing (2013); 6) Breeding and genetics (2013); 7) Hoof health (2012); 8) Nutrition (2012); 9) Worms (2011); and 10) Ewe/Doe Management (2011). Short courses were promoted via newsletters, web sites, social media, and a listserv. Each webinar lasted for approximately 1 hour. Additional time was allotted for questions. Interaction was via a chat box. Most webinar participants logged in from their home computers. Some attended group meetings. Live participation ranged from 26 to 86. Total live participation was 3264. Participants were from numerous states, provinces, and countries. All webinars were recorded and converted to YouTube videos (in 2015). Accompanying PowerPoint presentations were uploaded to SlideShare. To date, YouTube and SlideShare views total 22,167 and 212,199, respectively. Follow-up surveys showed that 90–100% of webinar participants learned something new that they planned to apply to their small ruminant enterprises. On a scale of 1–10 participants rated the information presented in the webinars as useful (8.5–9.5), easy-to-understand (8.6–9.4), and interesting (8.8–9.5). On-average, webinars increased subject matter knowledge by 26%. Webinar short courses have proven to be an excellent tool for educating sheep and goat producers.

Summary Objective To assess collagen network alterations occurring with flow and other abnormalities of articular cartilage at medial femoral condyle (MFC) sites repaired with osteochondral autograft (OATS) after 6 and 12 months, using quantitative polarized light microscopy (qPLM) and other histopathological methods. Design The collagen network structure of articular cartilage of OATS-repaired defects and non-operated contralateral control sites were compared by qPLM analysis of parallelism index (PI), orientation angle ( α ) relative to the local tissue axes, and retardance ( Γ ) as a function of depth. qPLM parameter maps were also compared to ICRS and Modified O'Driscoll grades, and cell and matrix sub-scores, for sections stained with H&E and Safranin-O, and for Collagen-I and II. Results Relative to non-operated normal cartilage, OATS-repaired regions exhibited structural deterioration, with low PI and more horizontal α , and unique structural alteration in adjacent host cartilage: more aligned superficial zone, and reoriented deep zone lateral to the graft, and matrix disorganization in cartilage overhanging the graft. Shifts in α and PI from normal site-specific values were correlated with histochemical abnormalities and co-localized with changes in cell organization/orientation, cloning, or loss, indicative of cartilage flow, remodeling, and deterioration, respectively. Conclusions qPLM reveals a number of unique localized alterations of the collagen network in both adjacent host and implanted cartilage in OATS-repaired defects, associated with abnormal chondrocyte organization. These alterations are consistent with mechanobiological processes and the direction and magnitude of cartilage strain.

Objective: The articular cartilage of autologous osteochondral grafts is typically different in structure and function from local host cartilage and thereby presents a remodeling challenge. The hypothesis of this study was that properties of the articular cartilage of trochlear autografts and adjacent femoral condyle are associated with the 3-dimensional (3-D) geometrical match between grafted and contralateral joints at 6 and 12 months after surgery. Design: Autografts were transferred unilaterally from the lateral trochlea (LT) to the medial femoral condyle (MFC) in adult Spanish goats. Operated and contralateral nonoperated joints were harvested at 6 and 12 months and analyzed by indentation testing, micro–computed tomography, and histology to compare 1) histological indices of repair, 2) 3-D structure (articular surface deviation, bone-cartilage interface deviation, cartilage thickness), 3) indentation stiffness, and 4) correlations between stiffness and 3-D structure. Results: Cartilage deterioration was present in grafts at 6 months and more severe at 12 months. Cartilage thickness and normalized stiffness of the operated MFC were lower than the nonoperated MFC within the graft and proximal adjacent host regions. Operated MFC articular surfaces were recessed relative to the nonoperated MFC and exhibited lower cartilage stiffness with increasing recession. Sites with large bone-cartilage interface deviations, both proud and recessed, were associated with recessed articular surfaces and low cartilage stiffness. Conclusion: The effectiveness of cartilage repair by osteochondral grafting is associated with the match of 3-D cartilage and bone geometry to the native osteochondral structure.

A number of osteoporotic patients under bisphosphonate treatment present persistent fragility fractures and bone loss despite good compliance. The objective of this 18-month prospective study was to investigate the effect of teriparatide [rhPTH(1–34)] in 25 female osteoporotics who were inadequate responders to oral bisphosphonates and to correlate microarchitectural changes in three consecutive iliac crest biopsies measured by micro-computed tomography (μCT) with bone mineral density (BMD) and bone serum markers. Scanned biopsies at baseline (M0), 6 months (M6), and 18 months (M18) demonstrated early significant (P

The US meat goat industry lags behind other livestock industries in the use of quantitative genetic evaluation. The Western Maryland Pasture-Based Meat Goat Performance Test was initiated in 2006 at the University of Maryland’s Western Maryland Research & Education Center (39º 30’ N/77º 44’ W). The purpose of the test was to identify genetically-superior meat goat bucks, especially those which exhibited resistance and resilience to internal parasites. From 2006–2016, 736 bucklings, of various breeds and crosses, were evaluated. One hundred producers from 20 states consigned one or bucks. Bi-weekly progress reports, summaries, and other information and data were shared via a blog (https://mdgoattest.blogspot.com), which has 218,346 cumulative page views from 523 blog posts. Many other programs were held in conjunction with the test, including sales, field days, youth programs, and carcass evaluation. Each year, top-performing bucks were identified and sold or retained for breeding, with 86% of consigners using the genetics from top-performing bucks in their breeding programs. Many more producers used the genetics from top-performing bucks by purchasing breeding stock and/or semen from consigners. Per survey data, consigning to the Maryland test improved the reputation of participating herds (80%), increased the demand and selling price for breeding stock (66–72%), and enabled the sale of semen from top-performers (38%). The test enabled participating producers to develop more parasite resistant herds (76%), improve the health and performance of their herds (73%), and improve their knowledge of parasite control (80%). The Western Maryland Pasture-Based Meat Goat Performance Test provided economic value to producers (71%), while contributing to the genetic improvement of the meat goat industry and serving as a valuable resource to producers.

Strontium ranelate (SR) is one therapeutic option for reducing risk of fracture in osteoporosis. The effects of SR treatment on hydroxyapatite (HA) previously altered by bisphosphonate (BP) administration remain to be established. Patients who have received long-term BP treatment and present with persistent high fracture risk are of particular interest. Paired iliac crest biopsies from 15 patients post-BP therapy were subjected to a baseline biopsy and a follow-up biopsy after treatment with 2 g SR day −1 after either 6 months ( n = 5) or 12 months ( n = 10). Dual energy X-ray absorptiometry scans, serum parameters and biochemical markers were obtained. Quantitative backscattered electron imaging and energy-dispersive X-ray analyses combined with micro-X-ray fluorescence determinations were performed to observe any mineralization changes. Static 2-D histomorphometry was carried out to evaluate cellular and structural indices. After 6 months of SR treatment, increases in osteoid surface and strontium content were observed, but no other indices showed significant change. After 12 months of SR treatment, there was a significant increase in bone volume and trabecular thickness, and further increases in strontium content and backscattered signal intensity. These structural changes were accompanied by increased numbers of osteoblasts and increased osteoid surface and volume. Additionally, low bone resorption, as measured by beta-cross-laps, and a low number of osteoclasts were observed. SR treatment led to increased strontium content within the BP–HA nanocomposites and to increased osteoid indices and bone volume, which is indicative of newly formed bone, while osteoclasts were still suppressed. These data points suggest that SR might be considered as a therapeutic option for patients following long-term BP treatment.

BACKGROUND CONTEXT Cellular bone matrices (CBM) are allograft products that combine demineralized bone with viable cancellous bone prepared to retain cells with skeletal tissue differentiation capabilities. Using an athymic rat model of posterolateral fusion, several commercially-available human CBMs were compared: Trinity ELITE (TEL; OrthoFix, Lewisville, TX, United States), ViviGen (VIV; DePuy Synthes, Raynham, MA, United States), Cellentra (CEL; Zimmer Biomet, Warsaw, IN, United States), Osteocel Pro (OCP; NuVasive, San Diego, CA, United States), Bio4 (BIO; Stryker, Kalamazoo, MI, United States) and map3 (MAP; RTI Surgical, Marquette, MI, United States). Iliac crest bone from syngeneic rats was used as a control to approximate the human gold standard. METHODS To allow for lot-to-lot variability, three different lots of each implant type were procured and each was used to implant five rats, for a total of 15 9-10 week old male rats per implant type. Each implant was stored, thawed, and prepared according to the manufacturer's instructions and all implantations occurred within the manufacturers’ time allowance for use after preparation. After anesthesia and preparation, a single posterior midline longitudinal skin and subcutaneous incision and bilateral longitudinal paraspinal myofascial incisions were made to expose the transverse processes and intertransverse membranes at the L4-5 level. The processes were decorticated and 0.3 cc of allograft implant or freshly harvested syngeneic iliac bone graft was placed bilaterally. Surgeons were blinded as to which implant was which. Incisions were closed with sutures to avoid any interference with in vivo animal microCT scans performed within 48 hours of surgery on all rats. The rats were euthanized 6 weeks after surgery and the lumbar spines harvested. A second microCT scan was taken and compared with the microCT taken at the time of implantation to assess fusion and bone remodeling. Stable fusion was also evaluated by manual palpation by three independent, blinded reviewers. MicroCT analysis was performed by an independent CRO (ImageIQ, Cleveland, OH, USA). All assessments were done by experienced evaluators blinded to the treatments. Anonymity of implant type was rigorously kept to avoid any bias. RESULTS By manual palpation, 5/15 (33%) rats of the syngeneic bone group were fused at 6 weeks. While TEL had 8/15 (53%) and CEL 11/15 (73%) rats with stable fusion, only 2/15 (13%) of VIV-implanted spines were fused and 0/15 (0%) of the OCP, BIO and MAP CBMs produced stable fusion. The TEL and CEL groups were significantly different from the other CBMs but not different from each other. MicroCT analysis indicated percentage increases in bone volume from the first measurement to the second for all groups, but only TEL and CEL had significant increases over the syngeneic bone control (TEL 65% and CEL 73% vs. syngeneic bone 21%, respectively). CONCLUSIONS Because the CBMs tested have distinct formulations and are likely processed differently, it is not surprising that the results would be different between the groups. While map3 has cells added at the time of surgery, the other CBMs are processed with cells adherent to the bone matrix. The claimed live cell and stem cell contents differ between products. Trinity ELITE and Cellentra were found to be significantly better than other implants at forming new bone and achieving fusion. The other CBMs did not produce greater bone formation than the control and were very poor at forming a solid fusion. These results suggest that there may be large differences in the ability of different CBMs to elicit a successful fusion in the posterolateral spine. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Osteoporosis is a common disease. In Germany, 25 % of men and women over 50 years of age, equivalent to 7.8 million people, suffer from osteoporosis, women more frequently than men. Besides there are a lot of other risk-factors for example long-term corticoid therapy. Fractures are the most important and expensive. The diagnosis is a combination of risk-factors, fractures and bone mineral density. Only 22 % of all patients suffering from osteoporosis get specific medication.

Interaction chromatography has been employed to validate that adsorption of poly[styrene-co-(4-bromostyrene)] (PBr(x) S) random copolymers, where x denotes the mole fraction of 4-bromostyrene (4-BrS) in PBr(x) S in solution depends on the average number of adsorptive segments, the type of adsorbing substrate, and on the co-monomer sequence distribution in PBr(x) S.

We study the effect of comonomer sequence distributions in random copolymers (RCPs) on RCP adsorption on flat impenetrable surfaces. RCP poly(styrene-co-4-bromostyrene) (PBrxS), where x denotes the mole fraction of 4-bromostryrene (4-BrS), is prepared by bromination of parent homopolystyrene. By varying the solvent quality during the bromination, either “truly random” (good solvent) or “random-blocky” (poor solvent) PBrxS RCPs are prepared. Adsorption studies of PBrxS from various solvents at silica surfaces reveal that the adsorption of PBrxS increases with (1) increasing blockiness of the macromolecule, (2) increasing content of 4-BrS in PBrxS, and (3) decreasing solvent quality. Additionally, the effect of comonomer sequence distribution on RCP adsorption is modeled in detail using a coarse-grained statistical mechanical model and fully atomistic simulations based on configurational-biased grand-canonical Monte Carlo (CB-GCMC) technique. The main result from the simulations can be summarized as follows...

Although Paget's disease of bone (PDB) is the second most common metabolic bone disease, to our knowledge, there is only one quantitative analysis on the histological and especially on the histomorphometric level. Therefore, the aim of this study was to analyze, on the basis of the Hamburg Bone Register, PBD in terms of incidence, skeletal distribution, malignant transformation, and histological and histomorphometric characteristics. Bone biopsies and patient files of 754 cases with histologically proven PDB were reviewed in a retrospective study. Quantitative static histomorphometry was performed on a representative subgroup of 247 biopsies derived from patients with manifestation of PDB at the iliac crest and compared with an age- and sex-matched control group. The peak incidence of PDB was between 70 and 80 yr of age. The majority of monostotic skeletal manifestation was localized at the os ilium, followed by the spine and femur. Histomorphometric results showed a high bone turnover with a significant increase in bone resorption and bone formation indices leading to an increased bone volume. Paget sarcoma was diagnosed in 6 of 754 patients, indicating a malignant transformation in 0.8% of the affected patients. Taken together, our study characterizes PDB in Germany on the basis of one of the largest cohorts of patients with histologically proven PDB. Moreover, for the first time, a quantitative histomorphometric approach was taken for >200 cases, where we could show local high bone mass lesions as a result of an increase of both osteoclast and osteoblast indices.

We report on the kinetics of the bromination of free polystyrene (PS) chains in bulk solution and those anchored on flat solid substrates by performing the bromination reaction in different solvents, including nitrobenzene (NB), 1-chlorodecane (CD), 1-chloroundecane (CUD), and 1-chlorododecane (CDD), at various temperatures. We find that bulk bromination of PS follows the second-order kinetic in bromine and the reaction rate increases with increasing dielectric constant of the solvent (e). In spite of eCDD > eCD, the bulk bromination kinetics of PS in CDD is slower than that in CD because of lower solubility of PS in CDD than in CD. In addition, we demonstrate that the reaction rates for brominating PS brushes anchored to flat solid substrates are much slower than those for brominating free PS chains in bulk solution. We attribute this behavior to steric hindrance due to PS confinement on the substrate.

Inthis report, we present a simple methodology facilitating theformation of A-B random copolymers with tunable sequencedistributions. We demonstrate that varying the degree ofblockiness in the sequence distribution of A and B monomershas a profound impact on the partition of random copolymersat interfaces.Random copolymers (RCPs) are long chain moleculesmade of covalently bound monomers comprising at least twodifferent chemical moieties (say, A and B). In addition to theoverall molecular weight, RCPs are characterized by theircomposition and monomer sequence distribution. The abilityof A-B RCPs to act as “homopolymers with tunable composi-tion”, ranging between A and B homopolymers, has recentlyattracted considerable attention in controlling polymer misci-bility

Strontium ranelate produces an early and sustained reduction of both vertebral and nonvertebral fractures in patients ≥80 years of age. Introduction: About 25–30% of the population burden of all fragility fractures in the community arise from women ≥80 years of age, because this population is at high risk for all types of fracture, particularly nonvertebral fractures. Despite this, evidence that therapies reduce the risk of both vertebral and nonvertebral fractures in this group is lacking. The aim of this study was to determine whether strontium ranelate, an agent that reduces the risk of vertebral and nonvertebral fractures in postmenopausal women >50 years of age, also reduces fractures in the elderly. Materials and Methods: An analysis based on preplanned pooling of data from two international, phase III, randomized, placebo-controlled, double-blind studies (the Spinal Osteoporosis Therapeutic Intervention [SOTI] and TReatment Of Peripheral OSteoporosis [TROPOS]) included 1488 women between 80 and 100 years of age followed for 3 years. Yearly spinal X-rays were performed in 895 patients. Only radiographically confirmed nonvertebral fractures were included. Results: Baseline characteristics did not differ in placebo and treatment arms. In the intent-to-treat analysis, the risk of vertebral, nonvertebral, and clinical (symptomatic vertebral and nonvertebral) fractures was reduced within 1 year by 59% (p = 0.002), 41% (p = 0.027), and 37% (p = 0.012), respectively. At the end of 3 years, vertebral, nonvertebral, and clinical fracture risks were reduced by 32% (p = 0.013), 31% (p = 0.011), and 22% (p = 0.040), respectively. The medication was well tolerated, and the safety profile was similar to that in younger patients. Conclusions: Treatment with strontium ranelate safely reduces the risk of vertebral and nonvertebral fractures in women with osteoporosis ≥80 years of age. Even in the oldest old, it is not too late to reduce fracture risk.

Aim We investigated the associations of apolipoprotein C-III (apoCIII) protein and apoCIII gene variation with microvascular disease complications in Type 1 diabetes. Methods The serum apoCIII concentration, and both a T −455 →C and a Sac I gene polymorphisms were determined in 409 patients in the DCCT/EDIC cohort of patients with Type 1 diabetes. Correlations with albumin excretion rate (AER) and the severity of retinopathy were investigated. Results Higher apoCIII concentrations were associated ( P r =.78), total ( r =.61) and LDL ( r =.40) cholesterol, apoAI ( r =.26), and apoB ( r =.50), AER ( r =.08), and the severity of retinopathy (ETDRS score, r =.11), and these relationships persisted after controlling for age, gender, body mass index (BMI), and HbA1c level. The apoCIII concentration was significantly higher in the group of patients with macroalbuminuria (AERs 300 mg/24 h) compared to the groups with microalbuminuria (AER 40–299 mg/24 h; P P P P −455 →C polymorphism nor a Sac I polymorphism in the 3′ UTR were associated with circulating apoCIII concentrations, nor the severity of nephropathy or retinopathy. Conclusions Elevated apoCIII levels have been associated with increased macrovascular disease risk. In the DCCT/EDIC cohort of patients, there was an independent positive association of apoCIII level with microvascular complications of Type 1 diabetes.

In order to evaluate the sensitivity of hepatocellular cultures to variations in both substrate stiffness and bioactive ligand presentation, hepatocytes were cultured on differentially compliant polyacrylamide gel discs functionalized with varying amounts of the ECM ligand, fibronectin (FN). Subconfluent cell cultures were established in a multiwell plate format enabling the systematic evaluation of cellular response to both underlying substrate rigidity and substrate ligand concentration. Hepatocellular morphogenesis, regulated by a combination of both ligand density and substrate compliance, resulted in a broad spectrum of patterns of cellular reorganization and assembly ranging from highly two-dimensionally spread cells to highly compact, three-dimensional spheroids. Cell compaction was promoted by increasing levels of substrate mechanical compliance and generally inhibited by increasing concentrations of substrate-bound FN. We identified regimes of substrate compliance in which cells are highly responsive or relatively insensitive to the level of substrate-based ligands. For example, while FN presentation did not have a large impact on cell morphogenesis for cultures on highly compliant gels (G' = 1.9 kPa), hepatocytes on "firm" substrates of intermediate compliance (G' = 5.6 kPa) exhibited approximately a 2-fold increase in cell area between the highest and lowest FN concentrations used in this study. Further, we show that increasing substrate compliance at constant ligand concentration results in increased levels of liver-specific albumin secretion while increasing levels of FN at constant substrate rigidity yield reduced liver-specific functional activity. These substrate-elicited differences in cell function also coincided with analogous changes in the transcript levels of metabolic, growth-related, and liver-specific gene markers. Notably, these results also demonstrated that "firm" gel substrates elicit the most hepatocyte functional sensitivity to substrate-based FN presentation. Overall, our findings indicate that hepatocellular responsiveness to ligand concentration can be acutely regulated by gradation of substrate compliance, suggesting that concerted biochemical and biophysical design strategies may be critical toward the fabrication of hepatospecific biomaterials that effectively support desired levels of liver-specific function.

Serum apolipoprotein C-III (apoCIII) concentration and apoCIII gene polymorphisms have been shown to be a risk factor for cardiovascular disease; however, the underlying mechanisms remain unclear. In addition, no studies have been performed that address these issues in type 1 diabetes. The current study investigated apoCIII protein and apoCIII gene variation in a normotriglyceridemic (82 +/- 57 mg/dL) population of patients with type 1 diabetes, the Diabetes Control and Complications Trial/Epidemiology of Diabetes Intervention and Complications (DCCT/EDIC) cohort. Blood samples were obtained in 409 patients after an overnight fast. Serum apoCIII concentration was highly correlated with multiple changes in lipids and lipoproteins that resulted in an adverse cardiovascular disease risk profile. Higher apoCIII concentrations were associated (P.0001) with increased triglycerides (r = 0.78), total (r = 0.61) and low-density lipoprotein (LDL) (r = 0.40) cholesterol, apoA-I (r = 0.26), and apoB (r = 0.50), and these relationships persisted after controlling for age, gender, body mass index (BMI), and hemoglobin A1c (HbA1c). Nuclear magnetic resonance (NMR) lipoprotein subclass analyses demonstrated that apoCIII was correlated with an increase in very-low-density lipoprotein (VLDL) subclasses (P = .0001). There also was a highly significant positive relationship between serum apoCIII concentration and the LDL particle concentration in both men (r = 0.49, P = .001) and women (r = 0.40, P = .001), and a highly significant negative relationship between serum apoCIII levels and average LDL particle size in both men (r = -0.37, P = .001) and women (r = -0.22, P = .001) due primarily to an augmentation in the small L1 subclass (r = 0.42, P = .0001). Neither the T(-455) --C polymorphism affecting an insulin response element in the apoCIII gene promoter nor a SacI polymorphism in the 3'UTR were associated with any alterations in circulating apoCIII concentrations, serum lipids, apolipoprotein concentrations, lipoprotein composition, or parameters measured by NMR lipoprotein subclass analyses. In summary, elevated apoCIII concentration was associated with risk factors for cardiovascular disease in normolipidemic type 1 diabetic patients through associated changes in lipoprotein subfraction distributions, which were independent of apoCIII genotype.

Monte Carlo simulation utilizing the bond fluctuation model in conjunction with single and configurational biased Monte Carlo moves is used to study the adsorption of diblock (A-block-B) and alternating (A-alt-B) copolymers at flat, chemically heterogeneous surfaces comprising C and D domains. The main objective of this work is to address the effect of the strength of attraction between the adsorbing surface domains, D, and the copolymer adsorbing segments, B, on the copolymer's ability to recognize the chemical pattern on the surface. The results of our simulations reveal that both block and alternating copolymers have the ability to recognize the surface motif and transcribe it into the bulk material. The extent to which diblock copolymers transfer the chemical pattern from the surface to the bulk is relatively unaffected when the attractive B-D potential is increased beyond a certain critical value. This behavior stems from the brush-like conformation adopted by the diblock copolymer at the substrate. In contrast to the diblock copolymer, the adsorption of the alternating copolymer is influenced by the strength of the attraction between the copolymer's adsorbing segments and the adsorbing domains on the surface. Since the B segments are distributed evenly along the backbone, the alternating copolymers are more likely to adopt conformations in which the whole chain is zipped to the surface. The resultant entropic frustration is then alleviated through an increased formation of loops with little change to their length. Such conformational changes endow the alternating copolymer with the ability to invert the substrate pattern as the distance away from the surface is increased.

We present results of Monte Carlo simulation studies utilizing the bond fluctuation model in conjunction with single and configurational biased Monte Carlo moves to investigate the adsorption of diblock (A–b–B) and alternating (A–alt–B) copolymers at physically flat surfaces made of an equal number of two chemically different sites, C and D. The adsorption of the copolymer to the surface is driven by the repulsion between the A and B segments along the copolymer and the attraction between the B segments and the D sites on the surface. We address the critical role of the commensurability between the copolymer’s monomer sequence distribution and the size and spatial distribution of the surface adsorbing sites on the copolymer adsorption. We show that both copolymer architectures have the ability to recognize the surface motif and transcribe it into the bulk material. Diblock copolymers can transfer the pattern once the heterogeneous domain sizes match the size of the parallel component to the radius of gyra...

— We examined whether plasma fibrinogen levels and the β-fibrinogen gene G−455→A polymorphism were related to microvascular or macrovascular disease in patients (n = 909) with type 1 diabetes enrolled in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/ EDIC). Univariate regression showed that fibrinogen levels were correlated with BMI (r = 0.15; P < 0.0001), HbA1c (r = 0.11; P = 0.0014), total cholesterol (r = 0.17; P < 0.0001), and LDL cholesterol (r = 0.16; P < 0.0001) in all patients. In men, but not women, waist-to-hip ratio (r = 0.20; P < 0.0001) and triglycerides (r = 0.13; P = 0.0047) also became powerful predictors of fibrinogen level; in women, but not men, fibrinogen was correlated with both diastolic (r = 0.16; P = 0.0011) and systolic (r = 0.11; P = 0.0241) blood pressure. Fibrinogen was correlated with urinary albumin excretion rates in men (r = 0.13; P = 0.0033), but not in women. In both sexes, however, the development of proteinuria (albumin excretion >300 mg/24 h) was accompanied by 1.5-fold increment in plasma fibrinogen compared with patients with normal excretion or microalbuminuria. In addition, high fibrinogen levels were associated with a lower average ankle-brachial index in women (r = −0.13; P = 0.0075), but not men. Multiple regression analyses demonstrated that plasma fibrinogen was independently correlated with high albumin excretion rate in men, and with low average ankle-brachial index in women. Fibrinogen was not correlated with the severity of retinopathy. Carotid artery intima-medial thickness was not correlated with fibrinogen, and the G−455→A polymorphism in the 5′ promoter region of the β-fibrinogen gene did not influence circulating fibrinogen levels. However, the presence of the more common G−455 allele was associated with greater intima-medial thickness in the internal carotid artery (ANCOVA P = 0.045). Last, hyperfibrinogenemia in type 1 diabetes is associated with components of the insulin resistance syndrome trait cluster, and the association is influenced by sex.

In the presence of a midblock-selective solvent, ABA triblock copolymers form physical gels in which bridged and entangled B-chains establish a swollen network stabilized by A-microdomains. Here, we seek to improve the properties of an ABA gel through the addition of an A-compatible, high-molecular-weight semicrystalline homopolymer (shA). Dynamic rheology indicates that the elastic modulus increases substantially, and far beyond that achievable with an inert filler, with increasing shA content at constant solvent concentration. Transmission electron micrographs reveal the existence of nanoscale shA filaments and sheets dispersed in a micelle-stabilized gel network. The shape of the nanoscale shA objects, which are partially crystalline according to differential scanning calorimetry, and their apparent interaction with the A-rich micelles enhance network development and are responsible for the pronounced modulus increase.

Die Osteoporose bei entzundlich-rheumatischen Erkrankungen stellt ein erhebliches klinisches Problem dar. Ein Teil des Problems ist durch die Einnahme von Steroiden zu erklaren. Deshalb ist die konsequente Durchfuhrung von Prophylaxe und Therapie (siehe Beitrag in diesem Heft) der Osteoporose bei rheumatischen Erkrankungen besonders wichtig. Hier gibt es in der taglichen Praxis noch einen erheblichen Nachholbedarf. Arzte, die Patienten mit rheumatischen und anderen entzundlichen Erkrankungen sowie solche unter Steroidmedikation behandeln, sollten die eindeutigen Interventionsindikationen beachten und mit zur Verhinderung osteoporotischer Frakturen beitragen. Osteoporosis in inflammatory rheumatic diseases is a considerable clinical problem. This can be partly ascribed to steroid intake. Hence it is of special importance in rheumatic diseases to pay particular attention to the strict performance of prophylaxis and treatment of osteoporosis (see Contribution in this issue). Daily practice needs a lot of catching up in this respect. Physicians treating patients suffering from rheumatic and other inflammatory diseases and patients who are being treated with steroids, should pay close attention to the unmistakable indications for intervention and thus be instrumental in preventing osteoporotic fractures.

We have reported previously that cellular stimulation induced by variable mechanochemical properties of the extracellular microenvironment can significantly alter liver-specific function in cultured hepatocytes (Semler et al., Biotech Bioeng 69:359-369, 2000). Cell activation via time-invariant presentation of biochemical growth factors was found to either enhance or repress cellular differentiation of cultured hepatocytes depending on the mechanical properties of the underlying substrate. In this work, we investigated the effects of dynamic growth factor stimulation on the cell growth and differentiation behavior of hepatocytes cultured on either compliant or rigid substrates. Specifically, hepatotrophic growth factors (epidermal and hepatocyte) were either temporally added or withdrawn from hepatocyte cultures on Matrigel that was crosslinked to yield differential degrees of mechanical compliance. We determined that the functional responsiveness of hepatocytes to fluctuations in GF stimulation is substrate specific but only in conditions in which the initial mechanochemical environment induced significant cell morphogenesis. Our studies indicate that in conditions under which hepatocytes adopted a "rounded" phenotype, they exhibited increased levels of differentiated function upon soluble stimulation and markedly decreased function upon the depletion of GF stimulation. In contrast, hepatocytes that assumed a "spread" phenotype exhibited slightly increased function upon the depletion of GF stimulation. By examining the functional responsiveness of hepatocytes of differential morphology to varied fluctuations in GF activation, insights into the ability of cell shape to "prime" hepatocyte behavior in dynamic microenvironments were elucidated. We report on the possibility of uncoupling and, thus, selectively manipulating, the concerted contributions of GF-induced cellular activation and substrate- and GF-induced cell morphogenesis toward induction of cell function.

Controlled activation of hepatocyte aggregation is critical to three-dimensional (3D) multicellular morphogenesis during native regeneration of liver as well as tissue reconstruction therapies. In this work, we quantify the stimulatory effects of two model hepatotrophic activators, epidermal growth factor (EGF) and hepatocyte growth factor (HGF), on the aggregation kinetics and liver-specific function of hepatocytes cultured on organotypic substrates with differing mechanical resistivity. Substrate-specific morphogenesis of cultured hepatocytes is induced on a tissue basement membrane extract, Matrigel, formulated at two distinct levels of mechanical compliance (storage modulus G', at oscillatory shear rate 1 rad/s, was 34 Pa for basal Matrigel and 118 Pa for crosslinked Matrigel). Overall, we report that growth factor stimulation selectively promotes the kinetics of aggregation in the form of two-dimensional corded aggregates on basal Matrigel and three-dimensional spheroidal aggregates on crosslinked Matrigel. Our analysis also indicates that costimulation with EGF and HGF (20 ng/mL each) cooperatively maximizes the kinetics of aggregation in a substrate-specific manner. In addition, we show that the role of growth factor stimulation on hepatocyte function is sensitively governed by the mechanical compliance of the substrate. In particular, on matrices with high compliance, costimulatory aggregation is shown to elicit a marked increase in albumin secretion rate, whereas on matrices with low compliance aggregation results in effective functional repression to basal, unstimulated levels. Thus, our studies highlight a novel interplay of physicochemical parameters of the culture microenvironment, leading to selective enhancement or repression of differentiated functions of hepatocytes, in concert with the activation of cellular morphogenesis.

In addition to the alendronate Osteoporosis Intervention Trial (FOSIT) core protocol 901-0A of 1908 enrolled patients, the use of peripheral quantitative computed tomography (pQCT) was explored for the assessment of response to therapy. Bone mineral and strength related parameters at two different sites at the distal radius were explored in a subset of the multicenter core study. One hundred and three patients were entered into the substudy and given either a daily dose of 10 mg of alendronate or placebo for 1 year. Measurements were done at months 0, 3, 6, and 12. Inclusion criteria were bone mineral density (BMD) measurements at the lumbar spine of -2 SD. The response to therapy was assessed by dual-energy X-ray absorptiometry in the lumbar spine and the hip, and by pQCT in the ultradistal and the shaft sites of the radius. In line with the FOSIT core study, alendronate increased BMD at the lumbar spine and the hip, and it decreased the serum biochemical markers of bone turnover. The substudy showed differences between the therapy and placebo group in trabecular bone density (8.4%, p = 0.095), in total density (6.8%, p = 0.009), and in the bone strength index (BSI) (15. 6 mm3, p = 0.037) at the ultradistal site due to treatment and no changes at the radius shaft. A significant correlation was observed between percentage changes from baseline in BMD of the lumbar spine, and in total density and bone strength at the ultradistal radius site in the treatment group, but not in the placebo group. Thus, the ultradistal radius site did respond to alendronate therapy. The increased bone density accompanied a significant gain in the BSI at the ultradistal site, a finding that might help explain the reduced wrist fractures in the alendronate Fracture Intervention Trial.

Indolent systemic mastocytosis (ISM) can trigger bone loss. However, the clinical relevance of different mast cell infiltration patterns for bone remains to be clarified. Here, we report increased bone turnover in individuals with ISM, and its extent is rather related to the type of mast cell distribution within the bone marrow than to the presence or absence of cutaneous manifestations.It is well established that ISM can trigger osteopenia or osteoporosis. However, neither the clinical relevance of the infiltration pattern of mast cells within the bone marrow nor the impact of the presence or absence of cutaneous mast cell infiltration has been elucidated.We retrospectively analysed 300 cases with histologically proven ISM of the bone marrow and performed quantitative histomorphometry for a subgroup of 159 patients that did not receive any treatment before the biopsies were taken. Most importantly, since 66 % of the patients displayed ISM without the characteristic skin lesions, we were able to compare ISM with or without cutaneous manifestation.We found that both forms of ISM were not only characterized by a decreased trabecular bone mass but also by an increased number of osteoclasts and osteoblasts. Interestingly, when we analysed these data in relation to mast cell distribution, we found that the bone cell numbers in cases with mast cell granulomas were significantly increased compared to cases with diffuse mast cell distribution. Moreover, evidence of increased bone turnover was also found in 16 patients displaying osteosclerosis.Based on the largest cohort of bone biopsies from patients with ISM analysed so far, we could demonstrate high bone turnover, more specifically increased osteoblast and osteoclast numbers and surface indices, as a cause of the skeletal changes. Moreover, the severity of the bone disease is presumably rather dependent on the amount of mast cells and their distribution within the bone marrow irrespective of the presence or absence of cutaneous involvement.

The physiological significance of sphingosine 1-phosphate (S1P) transport in blood has been debated. We have recently reported a comprehensive sphingolipid profile in human plasma and lipoprotein particles (VLDL, LDL, and HDL) using HPLC-MS/MS (Hammad et al., 2010). We now determined the relative concentrations of sphingolipids including S1P in the plasma subfraction containing lipoproteins compared to those in the remaining plasma proteins. Sphingomyelin and ceramide were predominantly recovered in the lipoprotein-containing fraction. Total plasma S1P concentration was positively correlated with S1P concentration in the protein-containing fraction, but not with S1P concentration in the lipoprotein-containing fraction. The percentage of S1P transported in plasma lipoproteins was positively correlated with HDL cholesterol (HDL-C) concentration; however, S1P transport in lipoproteins was not limited by the concentration of HDL-C in the individual subject. Thus, different plasma pools of S1P may have different contributions to S1P signaling in health and disease.

Author(s): Jobke, Bjorn; Burghardt, Andrew J; Muche, Burkhard; Hahn, Michael; Semler, Jutta; Amling, Michael; Majumdar, Sharmila; Busse, Bjorn | Abstract: BackgroundSeveral agents are available to treat osteoporosis while addressing patient-specific medical needs. Individuals' residual risk to severe fracture may require changes in treatment strategy. Data at osseous cellular and microstructural levels due to a therapy switch between agents with different modes of action are rare. Our study on a series of five consecutively taken bone biopsies from an osteoporotic individual over a six-year period analyzes changes in cellular characteristics, bone microstructure and mineralization caused by a therapy switch from an antiresorptive (bisphosphonate) to a dual action bone agent (strontium ranelate).Methodology/principal findingsBiopsies were progressively taken from the iliac crest of a female patient. Four biopsies were taken during bisphosphonate therapy and one biopsy was taken after one year of strontium ranelate (SR) treatment. Furthermore, serum bone markers and dual x-ray absorptiometry measurements were acquired. Undecalcified histology was used to assess osteoid parameters and bone turnover. Structural indices and degree of mineralization were determined using microcomputed tomography, quantitative backscattered electron imaging, and combined energy dispersive x-ray/µ-x-ray-fluorescence microanalysis.Conclusions/significanceMicrostructural data revealed a notable increase in bone volume fraction after one year of SR treatment compared to the bisphosphonate treatment period. Indices of connectivity density, structure model index and trabecular bone pattern factor were predominantly enhanced indicating that the architectural transformation from trabecular rods to plates was responsible for the bone volume increase and less due to changes in trabecular thickness and number. Administration of SR following bisphosphonates led to a maintained mineralization profile with an uptake of strontium on the bone surface level. Reactivated osteoclasts designed tunneling, hook-like intratrabecular resorption sites. The appearance of tunneling resorption lacunae and the formation of both mini-modeling units and osteon-like structures within increased plate-like cancellous bone mass provides additional information on the mechanisms of strontium ranelate following bisphosphonate treatment, which may deserve special attention when monitoring a treatment switch.

Introduction Longevity has resulted in a greater proportion of the population entering a time of life when increasing bone fragility and falls predispose to fractures, particularly nonvertebral fractures. Women over 80 years of age constitute 10% of the population but contribute 30% of all fractures and 60% of all nonvertebral fractures. Despite this, few studies have examined antifracture efficacy of treatments in this high-risk group and none has provided evidence for benefits beyond 3 years. Materials and methods To determine whether strontium ranelate reduces the risk of vertebral and nonvertebral fractures during 5 years, we analyzed a subgroup of 1489 female patients over 80 years of age (mean 83.5 ± 3.0 years) with osteoporosis from the SOTI (spinal osteoporosis therapeutic intervention) and TROPOS (treatment of peripheral osteoporosis) studies randomized to strontium ranelate 2 g/d or placebo. All received a supplement of calcium plus vitamin D. Results By intention to treat, vertebral fracture risk was reduced by 31% (relative risk, RR = 0.69; 95% confidence interval, CI 0.52-0.92), nonvertebral fracture risk by 27% (RR = 0.73; 95% CI 0.57-0.95), major nonvertebral fracture risk by 33% (RR = 0.67; 95% CI 0.50-0.89) and hip fracture risk by 24% (RR = 0.76; 95% CI 0.50-1.15, not significant). Treatment was cost-saving as it decreased cost and increased QALYs and life-years. Discussion Strontium ranelate safely produced a significant reduction in vertebral and nonvertebral fracture risk during 5 years in postmenopausal women over 80 years of age and was cost saving.

Interaction chromatography has been employed to validate that adsorption of poly[styrene-co-(4-bromostyrene)] (PBr(x) S) random copolymers, where x denotes the mole fraction of 4-bromostyrene (4-BrS) in PBr(x) S in solution depends on the average number of adsorptive segments, the type of adsorbing substrate, and on the co-monomer sequence distribution in PBr(x) S.

Gastric emptying of digestible solids occurs after trituration of food particles. Non-digestible solids are thought to empty with phase III of the migrating motor complex (MMC). The aim of this study was to determine if a non-digestible capsule given with a meal empties from the stomach with return of the fasting phase III MMC or during the fed pattern with the solid meal. Fifteen normal subjects underwent antroduodenal manometry and ingestion of a radiolabelled meal and SmartPill wireless pH and pressure capsule. In five subjects, emptying of the SmartPill was studied in the fasting period by ingesting the SmartPill with radiolabelled water. The SmartPill emptied from the stomach within 6 h in 14 of 15 subjects. SmartPill pressure recordings showed high amplitude phasic contractions prior to emptying. SmartPill gastric residence time (261 +/- 22 min) correlated strongly with time to the first phase III MMC (239 +/- 23 min; r = 0.813; P0.01) and correlated moderately with solid-phase gastric emptying (r = 0.606 with T-50% and r = 0.565 with T-90%). Nine of 14 subjects emptied the capsule with a phase III MMC. In five subjects, the SmartPill emptied with isolated distal antral contractions. In five subjects ingesting only water, SmartPill gastric residence time (92 +/- 44 min) correlated with the time to the first phase III MMC (87 +/- 30 min; r = 0.979; P0.01). The non-digestible SmartPill given with a meal primarily empties from the stomach with the return of phase III MMCs occurring after emptying the solid-phase meal. However, in some subjects, the SmartPill emptied with isolated antral contractions, an unappreciated mechanism for emptying of a non-digestible solid.

Introduction The wireless motility capsule (WMC) allows investigation of regional gut transit times, intraluminal pH and pressure changes as it traverses the gastrointestinal tract. It is a useful diagnostic tool to confirm slow transit constipation (STC), which recent studies suggest is allied to dysregulated rather than impaired colonic motility (Dinning et al . NGM 2010). Whether luminal pH differs in STC is unknown. AIM: to compare colonic pressure and pH profiles between healthy volunteers (HV) and STC. Method data from 18 WMC studies in STC (15 female, median age 37; colon transit time (CTT) >72h) were compared to those of 112 HV (48 female; median age 43). Pressure and pH profiles were analysed for: (1) the whole colon; (2) within the caecum and proximal colon (first 60 min following passage of WMC through the ICJ); and (3) within the distal colon (last 60 min prior to WMC expulsion). Results overall frequency of colonic contractions was similar between STC and HV (STC: 3.0 ± 1.3/min vs. HV: 2.8 ± 1.2/min; P =NS). However, the colonic motility index (CMI) was significantly higher in STC than HV (STC: 330 ± 166 vs. HV: 184 ± 104; P .0001). CMI and CTT were positively correlated ( r = 0 .38; P = 0 .003). The proximal and distal colonic pressure profiles were similar between groups. For colonic pH profile, STC had a significantly more alkaline pH, both overall (STC: 7.7 ± 1.0 vs. HV: 6.8 ± 0.7; P .0001), and in the distal colon (STC: 8.1 ± 1 vs. HV: 7.2 ± 0.9; P = 0 .0004). Using linear regression modelling, alkaline pH was associated with an increase in the CMI when controlling for age and gender between groups (beta=62.1; P = 0 .023). Conversely, proximal colonic pH was more acidic in STC, manifest as a greater difference in pH across the ICJ than in HV (STC delta ICJ: 1.8 ± 0.6 vs. HV: 1.3 ± 0.8; P Conclusion the CMI was found to be higher in STC than HV, supporting a more contemporary acceptance of underlying dysregulation of colonic contractility rather than “inertia”. Differences in colonic pH in STC may reflect alterations in regional gut microbiota (i.e. dysbiosis), resulting in excessive production of acidic metabolites in the proximal colon (e.g. short-chain fatty acids) of STC patients, and more alkaline metabolites in the distal colon (perhaps related to methanogenic activity). The observed associations between colonic pH, CMI and CCT warrants further investigation; conceivably, this may represent a biomarker to sub-classify constipated patients, and identify those who may benefit from antibiotic and/or dietary interventions Disclosure of interest None Declared.

The biophysical nature of the cellular microenvironment, in combination with its biochemical properties, can critically modulate the outcome of three-dimensional (3-D) multicellular morphogenesis. This phenomenon is particularly relevant for the design of materials suitable for supporting hepatocellular cultures, where cellular morphology is known to be intimately linked to the functional output of the cells. This review summarizes recent work describing biophysical regulation of hepatocellular morphogenesis and function and focuses on the manner by which biochemical cues can concomitantly augment this responsiveness. In particular, two distinct design parameters of the substrate biophysics are examined--microtopography and mechanical compliance. Substrate microtopography, introduced in the form of increasing pore size on collagen sponges and poly(glycolic acid) (PGLA) foams, was demonstrated to restrict the evolution of cellular morphogenesis to two dimensions (subcellular and cellular void sizes) or induce 3-D cellular assembly (supercellular void size). These patterns of morphogenesis were additionally governed by the biochemical nature of the substrate and were highly correlated to resultant levels of cell function. Substrate mechanical compliance, introduced via increased chemical crosslinking of the basement membrane, Matrigel, and polyacrylamide gel substrates, also was shown to be able to induce active two-dimensional (2-D, rigid substrates) or 3-D (malleable substrates) cellular reorganization. The extent of morphogenesis and the ensuing levels of cell function were highly dependent on the biochemical nature of the cellular microenvironment, including the presence of increasing extracellular matrix (ECM) ligand and growth-factor concentrations. Collectively, these studies highlight not only the ability of substrate biophysics to control hepatocellular morphogenesis but also the ability of biochemical cues to further enhance these effects. In particular, results of these studies reveal novel means by which hepatocellular morphogenesis and assembly can be rationally manipulated leading to the strategic control of the expression of liver-specific functions for hepatic tissue-engineering applications.

The biophysical nature of the cellular microenvironment, in combination with its biochemical properties, can critically modulate the outcome of three-dimensional (3-D) multicellular morphogenesis. This phenomenon is particularly relevant for the design of materials suitable for supporting hepatocellular cultures, where cellular morphology is known to be intimately linked to the functional output of the cells. This review summarizes recent work describing biophysical regulation of hepatocellular morphogenesis and function and focuses on the manner by which biochemical cues can concomitantly augment this responsiveness. In particular, two distinct design parameters of the substrate biophysics are examined--microtopography and mechanical compliance. Substrate microtopography, introduced in the form of increasing pore size on collagen sponges and poly(glycolic acid) (PGLA) foams, was demonstrated to restrict the evolution of cellular morphogenesis to two dimensions (subcellular and cellular void sizes) or induce 3-D cellular assembly (supercellular void size). These patterns of morphogenesis were additionally governed by the biochemical nature of the substrate and were highly correlated to resultant levels of cell function. Substrate mechanical compliance, introduced via increased chemical crosslinking of the basement membrane, Matrigel, and polyacrylamide gel substrates, also was shown to be able to induce active two-dimensional (2-D, rigid substrates) or 3-D (malleable substrates) cellular reorganization. The extent of morphogenesis and the ensuing levels of cell function were highly dependent on the biochemical nature of the cellular microenvironment, including the presence of increasing extracellular matrix (ECM) ligand and growth-factor concentrations. Collectively, these studies highlight not only the ability of substrate biophysics to control hepatocellular morphogenesis but also the ability of biochemical cues to further enhance these effects. In particular, results of these studies reveal novel means by which hepatocellular morphogenesis and assembly can be rationally manipulated leading to the strategic control of the expression of liver-specific functions for hepatic tissue-engineering applications.

Diabetes may induce both quantitative and qualitative changes in lipoproteins, especially low-density lipoprotein (LDL). Effects of LDL glycation on endothelial cell secretion of tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) have not been fully elucidated. Human aortic endothelial cell (HAEC) tPA and PAI-1 production were determined after incubation with LDL (50 to 500 microg/mL protein, 24 h) from three sources: (1) nondiabetic LDL (N-LDL) modified in vitro to form six preparations: native, nonmodified (N); glycated (G); minimally oxidized (MO); minimally oxidized and glycated (MOG); heavily oxidized (HO); and heavily oxidized and glycated (HOG); (2) in vivo glycated and relatively nonglycated LDL subfractions from type 1 diabetic patients; (3) LDL from type 1 diabetic patients and matched controls, which was subfractionated using density gradient ultracentrifugation. In experiments using LDL modified in vitro, the rate of tPA release by HAECs incubated with N-LDL (83 +/- 4 ng/mg cell protein/24 h) did not differ significantly from those incubated with G-LDL (73 +/- 7), MO-LDL (74 +/- 13), or MOG-LDL (66 +/- 15) and was not influenced by LDL concentration. The rate of PAI-1 release was similar in HAECs incubated with N-LDL (5.7 +/- 0.6 mug/mg cell protein/24 h), G-LDL (5.7 +/- 0.7), MO-LDL (5.5 +/- 0.8), or MOG-LDL (5.7 +/- 0.9) and was not influenced by LDL concentration. In contrast, tPA release was significantly decreased in cells incubated with LDL (10 microg/mL) modified extensively by oxidation, and averaged 45.2 +/- 5.0 and 43.7 +/- 9.9 ng/mg/24 h for HO-LDL and HOG-LDL, respectively, and was further decreased with increasing concentrations of the heavily oxidized LDL preparations. PAI-1 release was not significantly decreased relative to N-LDL in cells incubated with low concentrations (5 to 50 microg/mL) of HO-LDL and HOG-LDL, but was decreased to 3.2 +/- 0.5 and 3.1 +/- 0.7 microg/mg/24 h for HO-LDL and HOG-LDL at 200 microg/mL, respectively. Results using in vivo glycated versus nonglycated LDL showed that tPA and PAI-1 release did not differ between subfractions. Release of tPA averaged 5.11 +/- 0.6 and 5.12 +/- 0.7 ng/mg/24 h, whereas release of PAI-1 averaged 666 +/- 27 ng/mg/24 h and 705 +/- 30 ng/mg/24 h for nonglycated and glycated LDL subfractions, respectively. Using LDL of different density subclasses, tPA and PAI-1 release in response to LDL from diabetic patients compared with control subjects did not differ when HAECs were incubated with LDLs of increasing density isolated from each subject pair. We conclude that oxidation of LDL, but not glycation, may contribute to the altered fibrinolysis observed in diabetes.