Complications of Venous Thromboembolism Chemoprophylaxis in Lumbar Laminectomy With and Without Fusion.

BACKGROUND: The benefit of chemoprophylaxis (CPX) agents in preventing venous thromboembolism must be weighed against potential risks. Current literature regarding the efficacy of CPX after laminectomies with or without fusion is limited, with no clear consensus to inform guidelines. OBJECTIVE: This study evaluated the association between CPX and surgical complications after lumbar laminectomy with and without fusion. STUDY DESIGN: Retrospective study of patients at a single large academic institution. METHODS: The medical records of patients who underwent lumbar laminectomies with or without lumbar fusion from 2018 to 2020 were reviewed for demographics, surgical characteristics, CPX agents, postoperative complications, epidural hematomas, and wound drainage. Patients receiving CPX (n = 316) were compared with patients not receiving CPX (n = 316) via t test following propensity score matching, and patients on CPX were further stratified by fusion status. RESULTS: The CPX group had higher body mass index and American Society of Anesthesiologists grades. Rates of venous thromboembolism, epidural hematomas, infections, postoperative incision and drainage, transfusions, wound dehiscence, and reoperation were not associated with CPX. Moist dressings were more frequent, and average days of drain duration were longer with CPX. Overall postoperative complication rate and length of stay (LOS) were greater with CPX. The fusion subgroup had a lower Charlson Comorbidity Index, had a lower American Society of Anesthesiologists grade, was younger, had more women, and underwent more minimally invasive laminectomies. While estimated blood loss, operative times, and LOS were significantly greater in the fusion group, there was no difference in rate of intraoperative and postoperative complications. CONCLUSION: CPX after lumbar laminectomies with or without fusion was not associated with increased rates of epidural hematomas, wound complications, or reoperation. Patients receiving CPX had more postoperative cardiac complications, but it is possible that surgeons were more likely to prescribe CPX for higher-risk patients. They also had higher rates of ileus and moist dressings, greater LOS, and longer length of drain duration. Patients who underwent lumbar laminectomy with fusion on CPX tended to be lower risk yet incurred greater blood loss, operative times, LOS, cardiac complications, and hematomas/seromas than patients not undergoing fusion. CLINICAL RELEVANCE: This retrospective study compared surgical complications of lumbar laminectomies in patients who received chemoprophylaxis vs patients who did not. Chemoprophylaxis was not associated with increased rates of epidural hematomas, wound complications, or reoperation, but it was associated with higher rates of postoperative cardiac complications and ileus.

The Impact of Social Determinants of Health on Discharge Disposition Following One- and Two-Level Posterior Interbody Fusion.

Background Current research is limited in exploring the impact of social determinants of health (SDOH) on the discharge location within elective spine surgery. Further understanding of the influence of SDOH on disposition is necessary to improve outcomes. This study explores how SDOH influence discharge disposition for patients undergoing one- or two-level posterior interbody fusion (TLIF/PLIF). Methods This was a retrospective propensity-matched cohort study. Patients who underwent TLIF/PLIF between 2017 and 2020 at a single academic medical center were identified. The chart review gathered demographics, perioperative characteristics, intra/post-operative complications, discharge disposition, and 90-day outcomes. Discharge dispositions included subacute nursing facility (SNF), home with self-care (HSC), home with health services (HHS), and acute rehab facility (ARF). Demographic, perioperative, and disposition outcomes were analyzed by chi-square analysis and one-way ANOVA based on gender, race, and income quartiles. Results Propensity score matching for significant demographic factors isolated 326 patients. The rate of discharge to SNF was higher in females compared to males (25.00% vs 10.56%; p=0.001). Men were discharged to home at a higher rate than women (75.4% vs 61.95%; p=0.010). LatinX patients had the highest rate of home discharge, followed by Asians, Caucasians, and African Americans (83.33% vs 70.31% vs 66.45% vs 65.90%; p<0.001). The post hoc Tukey test demonstrated statistically significant differences between Asians and all other races in the context of age and BMI. Additionally, patients discharged to SNF showed the highest Charlson comorbidity index (CCI) score, followed by those at ARF, HHS, and HSC (4.36 vs 4.05 vs 2.87 vs 2.37; p<0.001). The estimated median income for the cohort ranged from $52,000 to $250,001, with no significant differences in income seen across comparisons. Conclusion Discharge disposition following one- or two-level TLIF/PLIF shows significant association with gender and race. No association was seen when comparing discharge rates among zip code-level median income quartiles.

Clinical outcomes and complications after biportal endoscopic spine surgery: a comprehensive systematic review and meta-analysis of 3673 cases.

PURPOSE: Current literature suggests that biportal spinal endoscopy is safe and effective in treating lumbar spine pathology such as lumbar disc herniation, lumbar stenosis, and degenerative spondylolisthesis. No prior study has investigated the postoperative outcomes or complication profile of the technique as a whole. This study serves as the first comprehensive systematic review and meta-analysis of biportal spinal endoscopy in the lumbar spine. METHODS: A PubMed literature search provided over 100 studies. 42 papers were reviewed and 3673 cases were identified with average follow-up time of 12.5 months. Preoperative diagnoses consisted of acute disc herniation (1098), lumbar stenosis (2432), and degenerative spondylolisthesis (229). Demographics, operative details, complications, and perioperative outcome and satisfaction scores were analyzed. RESULTS: Average age was 61.32 years, 48% male. 2402 decompressions, 1056 discectomies, and 261 transforaminal lumbar Interbody fusions (TLIFs) were performed. Surgery was performed on 4376 lumbar levels, with L4-5 being most common(61.3%). 290 total complications occurred, 2.23% durotomies, 1.29% inadequate decompressions, 3.79% epidural hematomas, and < 1% transient nerve root injuries, infections, and iatrogenic instability. Significant improvement in VAS-Back, VAS-Leg, ODI, and Macnab Scores were seen across the cohort. CONCLUSION: Biportal spinal endoscopy is a novel method to address pathology in the lumbar spine with direct visualization through an endoscopic approach. Complications are comparable to previously published rates. Clinical outcomes demonstrate effectiveness. Prospective studies are required to assess the efficacy of the technique as compared to traditional techniques. This study demonstrates that the technique can be successful in the lumbar spine.

Assessing Postoperative Pseudarthrosis in Anterior Cervical Discectomy and Fusion (ACDF) on Dynamic Radiographs Using Novel Angular Measurements.

STUDY DESIGN: A retrospective review of operative patients at a single institution. OBJECTIVE: The aim was to validate a novel method of detecting pseudarthrosis on dynamic radiographs. SUMMARY OF BACKGROUND DATA: A common complication after anterior cervical discectomy and fusion is pseudarthrosis. A previously published method for detecting pseudarthrosis identifies a 1 mm difference in interspinous motion (ISM), which requires calibration of images and relies on anatomic landmarks difficult to visualize. An alternative is to use angles between spinous processes, which does not require calibration and relies on more visible landmarks. MATERIALS AND METHODS: ISM was measured on dynamic radiographs using the previously published linear method and new angular method. Angles were defined by lines from screw heads to dorsal points of spinous processes. Angular cutoff for fusion was calculated using a regression equation correlating linear and angular measures, based on the 1 mm linear cutoff. Pseudarthrosis was assessed with both cutoffs. Sensitivity, specificity, inter-reliability and intrareliability of angular and linear measures used postoperative computed tomography (CT) as the reference. RESULTS: A total of 242 fused levels (81 allograft, 84 polyetheretherketone, 40 titanium, 37 standalone cages) were measured in 143 patients (mean age 52.0±11.5, 42%F). 36 patients (66 levels) had 1-year postoperative CTs; 13 patients (13 levels) had confirmed pseudarthrosis. Linear and angular measurements closely correlated ( R =0.872), with 2.3° corresponding to 1 mm linear ISM. Potential pseudarthroses was found in 28.0% and 18.5% levels using linear and angular cutoffs, respectively. Linear cutoff had 85% sensitivity, 87% specificity; angular cutoff had 85% sensitivity, 96% specificity for detecting CT-validated pseudarthrosis. Interclass correlation coefficients were 0.974 and 0.986 (both P <0.001); intrarater reliability averaged 0.953 and 0.974 ( P <0.001 for all) for linear and angular methods, respectively. CONCLUSIONS: The angular measure for assessing potential pseudarthrosis is as sensitive as and more specific than published linear methods, has high interobserver reliability, and can be used without image calibration. LEVEL OF EVIDENCE: 3.

Analysis of microsatellite instability in Korean patients with pancreatic cancer.

BACKGROUND: Pancreatic cancer (PC) is a dangerous malignancy with a high mortality rate. Diagnosing PC at an early stage is difficult, and approximately 5% of the patients survive for 5 years. Microsatellite instability (MSI) plays an important role in colorectal cancer (CRC) for prognosis and immunotherapy. Evaluation of MSI status is important as it is recognized biomarker for the positive response of immune checkpoint blockade therapy in cancer. To our knowledge, there is no report yet on the prevalence of MSI in Korean PC patients. Studies have reported conflicting prevalence of MSI in PC. METHODS: Therefore, to improve the likelihood of MSI identification in PC, we included 133 patients with PC; paired tumor and normal tissue DNA were isolated and MSI was analyzed using Promega panel and immunohistochemistry (IHC) was also performed. RESULTS: Our results from the Promega panel indicated that one (0.7%) tumor was MSI-high (MSI-H), 13 (9.8%) were MSI-low (MSI-L), and 119 (89.5%) were microsatellite stable (MSS). IHC result also confirmed dMMR in only one sample. CONCLUSIONS: The finding of low incidence of MSI-H observed by the Promega panel also matched IHC results, so this study suggested that in Korean PC patients, MSI prevalence is infrequent.

Bone Graft Options in Spinal Fusion: A Review of Current Options and the Use of Mesenchymal Cellular Bone Matrices.

BACKGROUND: Spinal fusion is the mainstay treatment for various spinal conditions ranging from lumbar and cervical stenosis to degenerative spondylolisthesis as well as extensive deformity corrections. A new emerging category of allograft is cellular bone matrices (CBMs), which take allogeneic mesenchymal stem cells and incorporate them into an osteoconductive and osteoinductive matrix. This study reviewed the current spinal fusion options and new emerging treatment options. METHODS: Articles were searched using PubMed. The search included English publications since January 1, 2014, using the search terms "cellular bone matrix," "mesenchymal stem cells spinal fusion," "spinal arthrodesis AND mesenchymal stem cells," and "spine fusion AND cellular bone matrix." RESULTS: Spinal fusion is accomplished through the use of allografts, autografts, and bone graft substitutes in combination or alone. An emerging category of allograft is CBMs, in which an osteoconductive and osteoinductive matrix is filled with mesenchymal stem cells. Studies demonstrate that CBMs have achieved equivalent or better fusion rates compared with traditional options for anterior cervical discectomy and fusions and posterolateral lumbar fusions; however, the studies have been retrospective and lacking control groups and therefore not ideal. CONCLUSIONS: Many treatment options have been successfully used in spinal fusion. Newer allografts such as CBMs have shown promising results in both animal and clinical studies. Further research is needed to determine the therapeutic dose of mesenchymal stem cells delivered within CBMs.

Patient Outcomes After Single-level Coflex Interspinous Implants Versus Single-level Laminectomy.

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: The aim of this study was to compare postoperative outcomes of Coflex interspinous device versus laminectomy. SUMMARY OF BACKGROUND DATA: Coflex Interlaminar Stabilization device (CID) is indicated for one- or two-level lumbar stenosis with grade 1 stable spondylolisthesis in adult patients, as an alternative to laminectomy, or laminectomy and fusion. CID provides stability against progressive spondylolisthesis, retains motion, and prevents further disc space collapse. METHODS: Patients ≥18 years' old with lumbar stenosis and grade 1 stable spondylolisthesis who underwent either primary single-level decompression and implantation of CID, or single-level laminectomy alone were included with a minimum 90-day follow-up at a single academic institution. Clinical characteristics, perioperative outcomes, and postoperative complications were reviewed until the latest follow-up. χ2 and independent samples t tests were used for analysis. RESULTS: Eighty-three patients (2007-2019) were included: 37 cases of single-level laminectomy (48.6% female) were compared to 46 single-level CID (50% female). CID cohort was older (CID 69.0 ±â€Š9.4 vs. laminectomy 64.2 ±â€Š11.0, P = 0.042) and had higher American Society of Anesthesiologists (ASA) grade (CID 2.59 ±â€Š0.73 vs. laminectomy 2.17 ±â€Š0.48, P = 0.020). CID patients had higher estimated blood loss (EBL) (97.50 ±â€Š77.76 vs. 52.84 ±â€Š50.63 mL, P = 0.004), longer operative time (141.91 ±â€Š47.88 vs. 106.81 ±â€Š41.30 minutes, P = 0.001), and longer length of stay (2.0 ±â€Š1.5 vs. 1.1 ±â€Š1.0 days, P = 0.001). Total perioperative complications (21.7% vs. 5.4%, P = 0.035) and instrumentation-related complication was higher in CID (10.9% vs. 0% laminectomy group, P = 0.039). There were no other significant differences between the groups in demographics or outcomes. CONCLUSION: Single-level CID devices had higher perioperative 90-day complications, longer operative time, length of stay, higher EBL compared to laminectomies alone. Similar overall revision and neurologic complication rates were noted compared to laminectomy at last follow-up.Level of Evidence: 3.

The Military Medical System and Wartime Injuries to the Spine.

War has historically been a major catalyst for advancement in military medical care and medicine in general. In our current conflicts, advances in battlefield medicine, evacuation techniques, and personal protective equipment have improved survival rates among members of the armed services. With increased survival, there has been increased prevalence of serious but nonfatal injuries, particularly from blunt and penetrating trauma. Blast injuries are the major cause of trauma and have both blunt and penetrating components. With respect to the spine, blasts have led to open, contaminated wounds that are complex and difficult to treat. Additionally, blasts have led to an increased incidence of lower lumbar burst fractures and lumbosacral dissociation. As these and other injuries are being seen more commonly during war, we must ensure that our military medical system is adapting to ensure we are taking care of our military personnel at the highest level.

Directional Change of Interfacial Electric Field by Carbon Insertion in Heterojunction System TiO2/WO3.

Z-scheme transfer is an ideal photocatalytic system with stronger redox ability, but its design and construction still lack understanding. Herein, the work function difference and the band bending are found to be the determining factors for the construction of the Z-scheme transfer mechanism of photoexcited charges in TiO2/WO3. The control of work function and band bending achieved by carbon insertion results from the hybridization of orbitals and redistribution of electron density, as demonstrated by ultraviolet photoelectron spectroscopy and photocatalytic analysis. The heterojunction system, TiO2/WO3, with controlled work function and band bending, shows 2 times faster •OH radical formation rate (0.011 µmol min-1) compared to the undisturbed system. First-principles calculation reveals that the changes in work function and band bending result in an interfacial electric field, which shifts the charge transfer mechanism from type II to Z-scheme. This work proves that the design of work function and band bending allows reconstructing charge transfer mechanism by forming the interfacial electric field in heterojunction systems.

MRI Radiological Predictors of Requiring Microscopic Lumbar Discectomy After Lumbar Disc Herniation.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To investigate radiological differences in lumbar disc herniations (herniated nucleus pulposus [HNP]) between patients receiving microscopic lumbar discectomy (MLD) and nonoperative patients. METHODS: Patients with primary treatment for an HNP at a single academic institution between November 2012 to March 2017 were divided into MLD and nonoperative treatment groups. Using magnetic resonance imaging (MRI), axial HNP area; axial canal area; HNP canal compromise; HNP cephalad/caudal migration and HNP MRI signal (black, gray, or mixed) were measured. T test and chi-square analyses compared differences in the groups, binary logistic regression analysis determined odds ratios (ORs), and decision tree analysis compared the cutoff values for risk factors. RESULTS: A total of 285 patients (78 MLD, 207 nonoperative) were included. Risk factors for MLD treatment included larger axial HNP area (P < .01, OR = 1.01), caudal migration, and migration magnitude (P < .05, OR = 1.90; P < .01, OR = 1.14), and gray HNP MRI signal (P < .01, OR = 5.42). Cutoff values for risks included axial HNP area (70.52 mm2, OR = 2.66, P < .01), HNP canal compromise (20.0%, OR = 3.29, P < .01), and cephalad/caudal migration (6.8 mm, OR = 2.43, P < .01). MLD risk for those with gray HNP MRI signal (67.6% alone) increased when combined with axial HNP area >70.52 mm2 (75.5%, P = .01) and HNP canal compromise >20.0% (71.1%, P = .05) cutoffs. MLD risk in patients with cephalad/caudal migration >6.8 mm (40.5% alone) increased when combined with axial HNP area and HNP canal compromise (52.4%, 50%; P < .01). CONCLUSION: Patients who underwent MLD treatment had significantly different axial HNP area, frequency of caudal migration, magnitude of cephalad/caudal migration, and disc herniation MRI signal compared to patients with nonoperative treatment.

Comment on: Does sugammadex decrease the severity of agitation and complications in pediatric patients undergoing adenotonsillectomy?

[No Abstract Available].

Retrolisthesis and lumbar disc herniation: a postoperative assessment of outcomes at 8-year follow-up.

BACKGROUND CONTEXT: Lumbar disc herniation and retrolisthesis have been shown to be significant degenerative changes that can be associated with back pain. Current literature has shown evidence that retrolisthesis is associated with similar baseline function in patients with L5-S1 disc herniation, but worse postoperative outcomes 2 years after lumbar discectomy. However, literature comparing long-term postoperative outcomes at 8-year follow-up in patients with L5-S1 disc herniation with retrolisthesis is lacking. PURPOSE: The purpose of the present study is to compare long-term postoperative outcomes at 8-year follow-up in patients with retrolisthesis and L5-S1 disc herniations to patients with L5-S1 disc herniations without retrolisthesis. STUDY DESIGN: Retrospective review of prospectively collected data from the Spine Patients Outcomes Research Trial (SPORT) database. PATIENT SAMPLE: Sixty-five patients who underwent lumbar discectomy for L5-S1 disc herniations with 8-year follow-up from the SPORT. OUTCOME MEASURES: Short Form (SF)-36 bodily pain scale, SF-36 physical function scale, Oswestry Disability Index, Sciatica Bothersomeness Index, and reoperation rate. METHODS: Baseline surgical parameters, length of stay, complication rates, reoperation rates, and outcome measures were recorded in the SPORT database. Follow-up data were collected at 6 weeks, 3 months, 6 months, 1 year, 2 years, 3 years, 4 years, 5 years, 6 years, 7 years, and 8 years. Retrolisthesis was defined as posterior subluxation ≥8%. Patients with and without retrolisthesis were compared using a mixed-effects model of longitudinal regression. Outcomes were calculated as time-weighted averages over 8 years. Reoperation rates were compared using the log-rank test based on time to first reoperation. RESULTS: One hundred-twenty five patients met inclusion criteria for the present study, including 29 patients with retrolisthesis (23.3%) and 96 patients who did not have retrolisthesis (76.7%). The greatest difference in clinical outcome measures was found at 2 years postoperatively. This was the only point at which both the Short Form-36 Bodily Pain scale (SF-36 BP) and PF showed significant differences between the retrolisthesis and nonretrolisthesis group. At 3 years, SF-36 BP was significantly lower in patients with retrolisthesis (39.9 vs. 52, p=.046). At 8-year follow-up, the presence of retrolisthesis in patients undergoing L5-S1 discectomy was not associated with worse outcome measure scores based on the area under the curve analysis for any metric investigated (SF-36 BP 41.4 vs. 47.1, p=.18; SF-36 Physical Function scale 38.9 vs. 45.4, p=.12; Oswestry Disability Index -39.4 vs. -34.8, p=.23; -11.6 vs. -10.4, p=.25) or a difference in reoperation rate (retrolisthesis group 10%, nonretrolisthesis group 17%, p=.41). CONCLUSIONS: While retrolisthesis can contribute to low back pain and dysfunction in patients undergoing lumbar discectomy for L5-S1 herniated nucleus pulposus in early follow-up, no significant difference was found in postoperative outcomes after 3 years. Additionally, retrolisthesis was not found to be associated with different reoperation rates at 8 years postoperatively.

A Photoenzymatic NADH Regeneration System.

A photoenzymatic NADH regeneration system was established. The combination of deazariboflavin as a photocatalyst with putidaredoxin reductase enabled the selective reduction of NAD+ into the enzyme-active 1,4-NADH to promote an alcohol dehydrogenase catalysed stereospecific reduction reaction. The catalytic turnover of all the reaction components was demonstrated. Factors influencing the efficiency of the overall system were identified.

Prognostic significance of Glasgow prognostic score in patients with acute exacerbation of idiopathic pulmonary fibrosis.

BACKGROUND AND OBJECTIVE: The Glasgow prognostic score (GPS) reflects the host systemic inflammatory response and is a validated independent prognostic factor in lung cancer. We investigated GPS as a potential predictive factor of clinical outcomes in idiopathic pulmonary fibrosis (IPF) patients with acute exacerbation (AE). METHODS: This was a retrospective study performed between January 2006 and March 2016 in Bucheon St. Mary's Hospital, The Catholic University of Korea. Overall, 327 admitted IPF patients were registered in the study. Patients with definite pneumonia at the time of admission, those with left-sided heart failure, pulmonary embolism and an identifiable cause of acute lung injury, and those whose albumin or C-reactive protein levels were not measured were excluded. RESULTS: A total of 66 patients hospitalized with IPF-AE were finally included. Median survival was 20.7 days and 29 (43.9%) patients died during hospitalization. The median length of overall survival (OS) was 26.0, 20.0 and 15.0 days for GPS-0, GPS-1 and GPS-2, respectively. There were significant differences in OS between GPS-0 and GPS-2 (P = 0.002). In a multivariate analysis performed using a Cox regression model, eosinopenia (P = 0.007), lower partial pressure of oxygen/fraction of inspired oxygen ratio (P = 0.014), and higher GPS (P = 0.006) were independent predictors of mortality. CONCLUSION: GPS can be helpful in predicting mortality in IPF patients with AE.

Thoracic juxtafacet cyst (JFC): a cause of spinal myelopathy.

Spinal cord compression due to synovial facet cyst in thoracolumbar spine is rare. Several etiologies of juxtafacet cysts (JFCs) in this location have been discussed, particularly overload of the arthritic facet joints. Due to the narrow caliber of the thoracic spine, JFC in this location can present with radicular pain or progressive myelopathy. We report an interesting case of a 67 year-old woman who presented with the signs and symptoms of thoracic myelopathy. A left-sided T11/12 JFC was identified on MRI and CT scans correlating with her myelopathy. She experienced a substantial improvement in her myelopathic symptoms after surgical excision of the JFC. The presentation, etiology, and therapeutic aspects of JFC are discussed in detail.

Development of a Reactive Plume Model for the Consideration of Power-Plant Plume Photochemistry and Its Applications.

A reactive plume model (RPM) was developed to comprehensively consider power-plant plume photochemistry with 255 condensed photochemical reactions. The RPM can simulate two main components of power-plant plumes: turbulent dispersion of plumes and compositional changes of plumes via photochemical reactions. In order to evaluate the performance of the RPM developed in the present study, two sets of observational data obtained from the TexAQS II 2006 (Texas Air Quality Study II 2006) campaign were compared with RPM-simulated data. Comparison shows that the RPM produces relatively accurate concentrations for major primary and secondary in-plume species such as NO2, SO2, ozone, and H2SO4. Statistical analyses show good correlation, with correlation coefficients (R) ranging from 0.61 to 0.92, and good agreement with the Index of Agreement (IOA) ranging from 0.76 to 0.95. Following evaluation of the performance of the RPM, a demonstration was also carried out to show the applicability of the RPM. The RPM can calculate NOx photochemical lifetimes inside the two plumes (Monticello and Welsh power plants). Further applicability and possible uses of the RPM are also discussed together with some limitations of the current version of the RPM.

The association between body mass index and duration spent on electronic devices in children and adolescents in Western Saudi Arabia.

[No Abstract Available].

Ozone production efficiency of a ship-plume: ITCT 2K2 case study.

Ozone production efficiency (OPE) of ship plume was first evaluated in this study, based on ship-plume photochemical/dynamic model simulations and the ship-plume composition data measured during the ITCT 2K2 (Intercontinental Transport and Chemical Transformation 2002) aircraft campaign. The averaged instantaneous OPEs (OPE(i)‾) estimated via the ship-plume photochemical/dynamic modeling for the ITCT 2K2 ship-plume ranged between 4.61 and 18.92, showing that the values vary with the extent of chemical evolution (or chemical stage) of the ship plume and the stability classes of the marine boundary layer (MBL). Together with OPE(i)‾, the equivalent OPEs (OPE(e)‾) for the entire ITCT 2K2 ship-plume were also estimated. The OPE(e)‾ values varied between 9.73 (for the stable MBL) and 12.73 (for the moderately stable MBL), which agreed well with the OPE(e)‾ of 12.85 estimated based on the ITCT 2K2 ship-plume observations. It was also found that both the model-simulated and observation-based OPE(e)‾ inside the ship-plume were 0.29-0.38 times smaller than the OPE(e)‾ calculated/measured outside the ITCT 2K2 ship-plume. Such low OPEs insides the ship plume were due to the high levels of NO and non-liner ship-plume photochemistry. Possible implications of this ship-plume OPE study in the global chemistry-transport modeling are also discussed.

Influence of red algal sulfated polysaccharides on blood coagulation and platelets activation in vitro.

The influence of sulfated polysaccharides (λ-, κ-, and κ/ß-carrageenan and porphyran) - on platelet activation was studied. Carrageenans were much weaker inhibitors of a coagulation process than heparin, while porphyran had not that effect. Results of the aPTT and PT assays suppose that carrageenans affected mostly intrinsic pathway of coagulation, while their effect on the extrinsic pathway is extremely low (λ and κ/ß) or absent (κ, LMW derivative of κ-carrageenan). λ-Carrageenan was the most potent anticoagulant agent in TT, aPTT, PT, and anti-factor Xa activity. This sample was also the strongest inhibitor of collagen-induced platelet aggregation in PRP. Generally, the correlation of anticoagulant and antithrombotic action in PRP is preserved for carrageenans but not for heparin. Carrageenans and porphyran affected platelet adhesion to collagen by influencing glycoprotein VI. Low molecular weight κ-carrageenan had a similar effect on platelet adhesion mediated with both major collagen receptors: integrin α2 ß1 and glycoprotein VI as native polysaccharide had. Carrageenans resulted in activation of platelets under platelet adhesion mediated by integrin αIIb ß3 with less degree than heparin. The least sulfated κ/ß-carrageenan that possessed an inhibiting effect on thrombin- and collagen-induced aggregation of washed platelets and on the PT test but it had no significant effect on TT was the weakest promoter of integrin αIIb ß3 mediated platelet activation. In summary, our study showed that the polysaccharide action was complex, since it depended on its molecular mass, sulfation degree, and monosaccharide contents (3,6-anhydrogalactose).