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Objective: Coronary CT angiography (CCTA) permits both qualitative and quantitative analysis of atherosclerotic plaque and may be a suitable risk modifier in assessing patients at intermediate risk of atherosclerotic cardiovascular disease. We sought to determine the association of plaque components with long-term major adverse cardiovascular events (MACEs) in asymptomatic intermediate-risk patients, compared with conventional coronary artery calcium (CAC) score., Methods: 100 intermediate-risk patients underwent double-blinded CCTA. Follow-up was conducted at 10 years and data were cross-referenced with the National Death Index. The primary outcome was MACE, which was a composite of death, acute coronary syndrome (ACS), revascularisation and stroke., Results: The median time from CCTA to follow-up was 9.5 years. 83 patients completed follow-up interview and mortality data were available on all 100 patients. MACE occurred in 17 (20.5%) patients, which included 2 (2%) deaths, 8 (10%) ACS, 3 (4%) strokes and 5 (6%) revascularisation procedures. 47 (57%) patients had mixed plaque, which was predictive of MACE (OR 4.68 (95% CI 1.19 to 18.5) p=0.028). The burden of non-calcified and mixed plaque, defined by non-calcified plaque segment stenosis score, was also a predictor of long-term MACE (OR 1.59 (95% CI 1.18 to 2.13) p=0.002). Neither calcified plaque (OR 3.92 (95% CI 0.80 to 19.3)) nor CAC score (OR 1.01 (95% CI 0.999 to 1.02)) was associated with long-term MACE., Conclusion: The presence and burden of mixed plaque on CCTA is associated with an increased risk of long-term MACE among asymptomatic intermediate-risk patients and is a superior predictor to CAC score., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: The goal in open tibial fracture management is to achieve a united tibia in an extremity that allows pain free mobilization. The objective of this study was to assess factors that lead to this functional outcome in lower limb reconstruction, from a plastic surgical perspective., Materials and Methods: The Plastic and Reconstructive Surgery lower limb database at a tertiary trauma hospital was searched for open tibial injuries from February 2015 to March 2020. The nature and severity of injury, timing and details of all operations including reconstructions were collected prospectively. Mobility including gait aids, pain, and complications were retrospectively collected. Union was assessed in two ways, depending on fracture location. Metaphyseal and diaphyseal tibial fractures were provided mRUST scores (union defined as RUST > 13) and epiphyseal tibial fractures were categorically classified as "united" or "non-union" by two independent radiologists., Results: During the five-year study period there were 148 open leg injuries in the database. Twenty-one patients underwent a primary amputation due to severity of their initial injury. One hundred patients underwent primary limb salvage. Sixty-one patients in the limb salvage group achieved primary tibial union with a mean follow-up time of 19.4 months post injury. Twenty-three additional patients were confirmed to subsequently unite. Patient who achieved union were more likely to mobilise without gait aids., Discussion: In this study definitive external fixation and soft tissue infection were both associated with higher rates of non-union. Longer times to soft tissue reconstruction was not associated with an increase in acute soft tissue complications. More importantly bone union, pain and mobility did not decline. After undertaking a primary limb salvage pathway for 100 patients, the ultimate tibial fracture union rate was 84% and the confirmed ambulation rate was 96%., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Sreedharan, Bruscino-Raiola, Lew, Ling and Ferris.)

Purpose: To assess the feasibility and outcomes of an approach utilizing transbasilic access for balloon-assisted maturation (BAM) of brachiocephalic arteriovenous fistulas (BCAVFs)., Materials and Methods: This retrospective analysis comprised 28 patients (mean age, 63 years ± 10.8) who underwent endovascular treatment of their immature BCAVFs via a basilic approach from December 2016 to December 2018. The mean age of the BCAVFs was 3.3 months ± 1.4 at the time of BAM. Other demographic data, vascular access characteristics, procedural data, technical and clinical success rates, and adverse events were also evaluated., Results: All patients had inflow juxta-anastomotic stenoses, with 4 patients (14%) having concomitant outflow tract stenoses and 1 patient (4%) having a short-segment occlusion at the stenotic juxta-anastomotic segment. Technical success was achieved in 27 patients (96%). The mean diameter of the largest balloon used was 5.7 mm ± 0.6. Clinical success was achieved in 22 patients (79%), with 6 patients (21%) requiring a subsequent additional intervention before successful cannulation. No perioperative adverse events were observed., Conclusions: The retrograde basilic approach is feasible, safe, and effective for BAM of BCAVFs., (Copyright © 2022 SIR. Published by Elsevier Inc. All rights reserved.)

Objective: The objective of this study was to assess the frequency, type, and severity of errors associated with intravenous medication administration before and after smart pump interoperability., Methods: We conducted an observational study at a community healthcare system before and after implementing smart pump interoperability. Point prevalence methodology was used to collect data on medication administration and errors in adult inpatient settings., Results: Observations were completed for 350 infusions preintervention (178 patients) and 367 postintervention (200 patients). Total errors significantly decreased from 401 (114.6 per 100 infusions) to 354 (96.5 per 100 infusions, P = 0.02). Administration errors decreased from 144 (41.1 per 100 infusions) to 119 (32.4 per 100 infusions, P = 0.12). Expired medication errors significantly reduced from 11 (3.1 per 100 infusions) to 2 (0.5 per 100 infusions, P = 0.02). Errors involving high-risk medications significantly reduced from 45 (12.8 per 100 infusions) to 25 (6.8 per 100 infusions, P = 0.01). Errors involving continuous medications significantly reduced from 44 (12.6 per 100 infusions) to 22 (6.0 per 100 infusions, P = 0.005). When comparing programming type, manual programming resulted in 115 (77.2%) of administration and user documentation errors compared with 34 errors (22.8%) that occurred when autoprogramming was used. Of these, errors involving high-risk medications reduced from 21 (84.0%) to 4 (16.0%) after using autoprogramming., Conclusions: Smart pump interoperability resulted in a 16% reduction in medication administration errors. Despite using dose error reduction software and autoprogramming, some types of errors persisted. Further studies are needed to understand how technology use can be optimized., Competing Interests: The authors disclose no conflict of interest., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc.)

Context: Abnormally increased hepatic glucose production contributes to hyperglycemia in diabetes. Interventions that suppress hepatic gluconeogenesis should be beneficial in improving glycemic control in patients with diabetes., Objectives: It has been suggested that hepatic FTO is involved in glycemic control by regulating gluconeogenesis. Both FTO and activating transcription factor 4 ( ATF4 ) positively regulate the expression of gluconeogenic genes in the liver, suggesting the possibility that ATF4 mediates the stimulatory effect of FTO on hepatic gluconeogenesis. The present study aimed to determine the effect of altered expression or activity of FTO on Atf4 and gluconeogenic gene expression in hepatocyte cells., Methods: Mouse hepatocyte AML12 cells were treated with the FTO inhibitor rhein or transfected with an FTO -expressing plasmid. Levels of gluconeogenic glucose-6-phosphatase ( G6pc ) and Atf4 mRNA and protein were measured., Results: Rhein treatment significantly reduced G6pc mRNA levels as well as Atf4 mRNA and protein levels. Conversely, enhanced FTO expression caused an increase in G6pc and Atf4 mRNA levels., Conclusions: These findings support the hypothesis that hepatic FTO participates in the regulation of hepatic gluconeogenic gene and ATF4 expression. Reducing the activity of the hepatic FTO - ATF4 pathway may be beneficial in reducing hepatic glucose production and ameliorating hyperglycemia in diabetes., (©by Acta Endocrinologica Foundation.)

Objective: Posterior fixation with interbody cage placement can be accomplished via numerous techniques. In an attempt to expedite recovery by limiting muscle dissection, midline lumbar interbody fusion (MIDLIF) has been described. More recently, the authors have developed a robot-assisted MIDLIF (RA-MIDLIF) technique. The purpose of this study was to compare the index episode-of-care (iEOC) parameters between patients undergoing traditional open transforaminal lumbar interbody fusion (tTLIF), MIDLIF, and RA-MIDLIF., Methods: A retrospective review of a prospective, multisurgeon surgical database was performed. Consecutive patients undergoing 1- or 2-level tTLIF, MIDLIF, or RA-MIDLIF for degenerative lumbar conditions were identified. Patients in each cohort were propensity matched based on age, sex, smoking status, BMI, diagnosis, American Society of Anesthesiologists (ASA) class, and number of levels fused. Index EOC parameters such as length of stay (LOS), estimated blood loss (EBL), operating room (OR) time, and actual, direct hospital costs for the index surgical visit were analyzed., Results: Of 281 and 249 patients undergoing tTLIF and MIDLIF, respectively, 52 cases in each cohort were successfully propensity matched to the authors' first 55 RA-MIDLIF cases. Consistent with propensity matching, there was no significant difference in age, sex, BMI, diagnosis, ASA class, or levels fused. Spondylolisthesis was the most common indication for surgery in all cohorts. The mean total iEOC was similar across all cohorts. Patients undergoing RA-MIDLIF had a shorter average LOS (1.53 days) than those undergoing either MIDLIF (2.71 days) or tTLIF (3.58 days). Both MIDLIF and RA-MIDLIF were associated with lower EBL and less OR time compared with tTLIF., Conclusions: Despite concerns for additional cost and time while introducing navigation or robotic technology, a propensity-matched comparison of the authors' first 52 RA-MIDLIF surgeries with tTLIF and MIDLIF showed promising results for reducing OR time, EBL, and LOS without increasing cost.

Study Design: Systematic review and case series., Objectives: Any acute injury to the posterior elements of the lumbar spine resulting in listhesis is considered a traumatic spondylolisthesis. This rare injury caused by high-energy trauma is variably described in the literature as fracture-dislocation, where only case reports and series have been published. Our objectives were to propose evidence-based treatment recommendations and a new classification system for this injury., Methods: A systematic review of literature from PubMed, EMBASE, and Cochrane without time frame limitations was performed, which included 77 level IV and V articles and 9 patients as case series in the analysis., Results: A total of 125 cases were reviewed with mean age of 30.5 years. Half of the cases resulted from a vehicular accident. Back pain presented in 82%, while 50% had neurologic deficits. Operative treatment was performed in 93.6% (posterior decompression [PD] = 4%; posterior spinal fusion [PSF] = 43.2%; interbody fusion [IB] = 46.4%) with overall fusion rates of 74%. Binomial regression analysis for achieving solid fusion showed a 28.6× higher odds for IB compared to PSF ( P = .008, r 2 = 0.633). Subanalysis of cases with disc injuries revealed higher fusion outcomes for IB (87%) compared to PSF (46%; P = .006), while there were no significant differences for patients without disc injury. Pain and neurological symptoms improved significantly on final follow-up ( P < .001). Overall complication rate was 22%., Conclusion: Operative management with reduction, decompression for neurologic deficits, instrumentation, and fusion is recommended for traumatic spondylolisthesis. Interbody fusion is recommended to achieve better fusion outcomes especially with preoperatively identified disc lesions., Competing Interests: Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: MLPV has no conflicts of interest to disclose. JRD is an employee of Norton Healthcare; receives royalties, consulting and speaker fees from Medtronic; consultant for DePuy and K2; board member for the Federation of Spinal Associations (FOSA); Member of Board of Directors of the Scoliosis Research Society. LYC is an employee of Norton Healthcare; Member, Editorial Advisory Board, Spine Deformity, Spine, and Spine Journal; Institutional Review Board Member, University of Louisville; Research Committee Member, Scoliosis Research Society; receives research funds from the Orthopedic Research and Educational Fund, 2013-present; received funds for travel for study planning meetings from the Center for Spine Surgery and Research of the University of Southern Denmark; University of Louisville. Authors’ institution received research support from Norton Healthcare, Integra, IntelliRod, and Pfizer.

Background: Transcatheter aortic valve implantation (TAVI) is increasingly used for intermediate- and high-risk patients with severe symptomatic aortic stenosis (AS). However, safe undertaking of the procedure may be precluded by various anatomic factors. This study sought to identify prevalence of factors that prevent progression to TAVI., Methods: TAVI candidates with severe AS undergoing workup coronary angiography and iliac vessel angiography (±cardiac-gated CT) were identified and factors precluding TAVI were reviewed retrospectively from a single-centre cardiac database over a 10-year period., Results: 197 patients were included; mean age was 81.5±6.5years (±SD); 46.2% were male. 26.9% of TAVI candidates could not proceed to femoral access TAVI due to various factors including unsuitable peripheral vasculature (13.2%), untreated coronary artery disease (CAD) deemed high risk for TAVI (8.1%), unfavourable aortic characteristics (4.1%), and low-lying coronary ostia (1.5%). Factors associated with unsuitable femoral vasculature included female gender (p<0.01) and any CAD (p=0.03). Factors associated with the presence of unrevascularised CAD included male gender (p<0.01), estimated glomerular filtration rate (eGFR)<30mL/min/1.73m 2 (p=0.02), history of CAD (p<0.01), while prior percutaneous coronary intervention (PCI) or bypass surgery were protective (both p<0.01). Rates of progression to TAVI have increased over the last 10 years (p<0.01) from 58.3% prior to 2012 to 83.7% in 2016 and 2017, while incidence of unsuitable peripheral vasculature preventing TAVI (p=0.01) and CAD deemed unsuitable for TAVI (p=0.04) have both decreased., Conclusions: Non-progression to TAVI among higher risk patients with severe AS has become less common over the last 10 years with improvements in operator experience, lower profile devices, and wider ranges of valve sizes., (Copyright © 2018. Published by Elsevier B.V.)

Nowadays, most of the commonly used superabsorbent polymers (SAPs) are derived from synthetic polymers, particularly acrylic acid and its copolymers made with acrylamide. Here, we describe a novel and environmentally friendly aqueous-based process for fabrication of a new, natural, cellulose-based SAP (hydrogel). In this two-step process, cellulose was first reacted with sodium monochloroacetate (MCA) to obtain carboxymethyl cellulose (CMC) and then cross-linked with epichlorohydrin (ECH). In distilled water (d-water), the water retention value (WRV) of the newly fabricated hydrogels reached 725 g d-water/g gel, which is significantly greater than any other commercially available superabsorbent cellulose-based material (WRV of 10-100 g/g) and comparable to the commercial synthetic (polyacrylate) SAP gels (WRV of up to 1000 g/g). In saline water (s-water; 0.9% NaCl), the maximum WRV attained was 118 g s-water/g gel, which exceeds more than 2-fold the WRV of commercial gels (40-50 g/g). Compositional analysis was carried out to determine the amount of carboxyl groups and average molecular mass, and the parameters for hydrogel preparation were optimized. The natural SAP was characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The hydrogels showed good re-swelling properties losing only 5-10% of their capabilities to reabsorb d-water when reused in four consecutive cycles. Because of their superior swelling properties in physiological saline, the new hydrogels can compete with their synthetic counterparts in applications such as high-value hygiene and biomedical products., Competing Interests: The authors declare no competing financial interest.

Background: Lichens provide a large array of compounds with the potential for pharmaceutical development. In the present study, extracts from three previously undescribed North American lichen species were examined for antioxidant, antibacterial and anticancer activities., Results: The results from this study demonstrated the following: (i) Acarospora socialis ethanol extract exhibited significant DPPH antioxidant scavenging activities, which were concentration dependent; (ii) acetone and ethyl acetate extracts of Xanthoparmelia mexicana inhibited Gram-positive bacteria but had no effect on Gram-negative bacteria; X. mexicana acetone extract yielded a minimum inhibitory concentration (MIC) of 20.9 µg mL -1 against Staphylococcus aureus, and 41.9 µg mL -1 against Enterococcus faecalis; (iii) acetone extract of Lobothallia alphoplaca inhibited growth of cultured breast cancer MCF-7 cells with an effective concentration (EC 50 ) of 87 µg mL -1 ; the MCF-7 cell cycle appears arrested in the G2 phase, whereas the DNA synthesis cell cycle (S) may be inhibited., Conclusion: New lichen species that possess strong biological activities have been identified. These lichens comprise secondary metabolites that possess antioxidant, antibacterial and anticancer properties. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)

Although cellulosic fibers are increasingly used in textile products, current methods for production of cellulose-based textiles suffer certain economic and/or environmental drawbacks. We have developed a new, cost-effective and environmentally-friendly (CS 2 -free) process that overcomes some of the shortcomings of existing technologies. The process is based on a modified method for periodate oxidation of cellulose that is then cross-linked with chitosan and extruded to obtain cellulosic fibers in the form of textile fibers. The produced fibers have low content of aldehyde groups (∼2mmol/g cellulose) and water retention values of 1.5-2.0g/g fibers. The new process makes use of both hardwood and softwood pulps, and offers significant yield advantages over the use of dissolving pulp as a raw material. The mechanical, water absorbency and morphological properties of the new textile fibers and their potential applications are discussed. The potential techno-economic and environmental benefits of the process are summarized., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

A strictly anaerobic, thermophilic bacterium, designated strain YS13, was isolated from a geothermal hot spring. Phylogenetic analysis using the 16S rRNA genes and cpn60 UT genes suggested strain YS13 as a species of Thermoanaerobacter. Using cellobiose or xylose as carbon source, YS13 was able to grow over a wide range of temperatures (45-70 °C), and pHs (pH 5.0-9.0), with optimum growth at 65 °C and pH 7.0. Metabolic profiling on cellobiose, glucose, or xylose in 1191 medium showed that H2, CO2, ethanol, acetate, and lactate were the major metabolites. Lactate was the predominant end product from glucose or cellobiose fermentations, whereas H2 and acetate were the dominant end products from xylose fermentation. The metabolic balance shifted away from ethanol to H2, acetate, and lactate when YS13 was grown on cellobiose as temperatures increased from 45 to 70 °C. When YS13 was grown on xylose, a metabolic shift from lactate to H2, CO2, and acetate was observed in cultures as the temperature of incubation increased from 45 to 65 °C, whereas a shift from ethanol and CO2 to H2, acetate, and lactate was observed in cultures incubated at 70 °C.

Demethylation of industrial lignin has been for long coveted as a pathway to the production of an abundant natural substitute for fossil-oil derived phenol. In an attempt to possibly identify a novel Kraft lignin-demethylating enzyme, we surveyed a collection of fungi by using selected ion flow tube-mass spectrometry (SIFT-MS). This method readily identifies methanol resulting from lignin demethylation activity. Absidia cylindrospora, and unidentified Cylindrocladium sp. and Aspergillus sp. were shown to metabolize lignin via different pathways, based on the HPLC analysis of lignin fragments. Of these three, Cylindrocladium and Aspergillus were shown to retain most of the lignin intact after 3 weeks in culture, while removing about 40% of the available methoxy groups. Our results demonstrate that after optimization of culture and lignin recovery methods, biological modification of Kraft lignin may be a feasible pathway to obtaining demethylated lignin for further industrial use., (Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.)

Lactic acid is an intermediate-volume specialty chemical for a wide range of food and industrial applications such as pharmaceuticals, cosmetics and chemical syntheses. Although lactic acid production has been well documented, improved production parameters that lead to reduced production costs are always of interest in industrial developments. In this study, we describe the production of lactic acid at high concentration, yield and volumetric productivity utilizing a novel homofermentative, facultative anaerobe Enterococcus faecalis CBRD01. The highest concentration of 182 g lactic acid l(-1) was achieved after 38 h of fed-batch fermentation on glucose. The bacterial isolate utilized only 2-13% of carbon for its growth and energy metabolism, while 87-98% of carbon was converted to lactic acid at an overall volumetric productivity of 5 g l(-1)  h(-1). At 13 h of fermentation, the volumetric productivity of lactate production reached 10.3 g l(-1)  h(-1), which is the highest ever reported for microbial production of lactic acid. The lactic acid produced was of high purity as formation of other metabolites was less than 0.1%. The present investigation demonstrates a new opportunity for enhanced production of lactic acid with potential for reduced purification costs., (© 2014 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.)

Metabolic engineering is a powerful biotechnological tool that finds, among others, increased use in constructing microbial strains for higher lactic acid productivity, lower costs and reduced pollution. Engineering the metabolic pathways has concentrated on improving the lactic acid fermentation parameters, enhancing the acid tolerance of production organisms and their abilities to utilize a broad range of substrates, including fermentable biomass-derived sugars. Recent efforts have focused on metabolic engineering of lactic acid bacteria as they produce high yields and have a small genome size that facilitates their genetic manipulation. We summarize here the current trends in metabolic engineering techniques and strategies for manipulating lactic acid producing organisms developed to address and overcome major challenges in the lactic acid production process., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Aims: The optimal management of asymptomatic subjects at intermediate risk of coronary artery disease (CAD) is often uncertain. Re-stratification to a high- or low-risk category may enable optimization of preventative strategies. Coronary computed tomographic angiography (CCTA) enables a minimally invasive assessment of coronary artery plaque quantity and composition. Non-calcified plaque by CCTA is lipid-rich and more vulnerable to rupture and resultant acute coronary syndromes. The purpose of this study was to determine whether novel approaches to CAD risk stratification, such as plasma lipid profiling, may predict non-calcified plaque burden in intermediate risk subjects., Methods and Results: CCTA and several markers of CAD (including plasma lipid profiling, carotid intima-media thickness, aortic pulse wave velocity, and high-sensitivity C-reactive protein) were prospectively performed in 100 asymptomatic patients at intermediate CAD risk according to the Framingham risk score. Segment stenosis scores (SSS) were calculated to evaluate the burden of total, calcified, and non-calcified coronary artery plaque. Non-calcified plaque was observed in 66 subjects and 158 (11%) of 1425 coronary artery segments. Eighteen lipid species demonstrated significant associations with non-calcified plaque burden, but not with total plaque or calcified plaque burden. No other marker of CAD was found to predict coronary artery plaque burden., Conclusions: Plasma lipidomic analysis can predict the burden of non-calcified coronary plaque in asymptomatic subjects at intermediate risk of CAD. Re-stratification of these patients by plasma lipid profiling may enable more appropriate and effective primary prevention management strategies., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)

We report here the draft genome sequence of the novel homofermentative Enterococcus faecalis isolate CBRD01, which is capable of high lactic acid productivity and yields, with minimal nutritional requirements. The genome is 2.8 Mbp, with 37% G+C, and contains genes for two lactate dehydrogenase (LDH) enzymes found in related organisms.

Askin tumor is a rare disease which had previously been reported as being thallium-201 and gallium-67 avid. Varying data regarding 18F- fluorodeoxyglucose metabolism has been described with Ewing family of soft tissue tumors. In this case, we present a patient found to have an Askin tumor of the left chest wall which demonstrated indium-111 pentetreotide and technetium-99m MIBI avidity. The lesion did not show 18F- fluorodeoxyglucose hypermetabolism in this case despite the aggressiveness of the tumor. The patient was treated with surgical excision of the tumor and chemotherapy. Subsequently, contrast enhanced CT, indium-111 pentetreotide and technetium 99m-MIBI showed that the lesion had regressed. These findings suggest that Askin tumor can demonstrate Indium-111 pentetreotide and technetium 99m-MIBI uptake and need not be hypermetabolic on 18F-fluorodeoxyglucose exam.

Context: Lichens are composite organisms consisting of a symbiotic association of a fungus (the mycobiont) with a photosynthetic partner (the phytobiont), usually either a green alga or cyanobacterium. The morphology, physiology and biochemistry of lichens are very different from those of the isolated fungus and alga in culture. Lichens occur in some of the most extreme environments on the Earth and may be useful to scientists in many commercial applications., Objective: Over the past 2 decades, there has been a renewed and growing interest in lichens as a source of novel, pharmacologically active biomolecules. This review summarizes the past and current research and development trends in the characterization and use of lichens and their bioactive compounds in traditional medicine and other biopharmaceutical applications of commercial interest., Methods: The present review contains 10 illustrations and 188 references compiled from major databases including Science Direct, Chemical Abstracts, PubMed and Directory of Open Access Journals., Results: Lichen morphology, symbiosis, diversity and bioactivities including enzyme inhibitory, antimicrobial, antifungal, antiviral, anticancer, anti-insecticidal and antioxidant actions were reviewed and summarized. Recent progress in lichens and lichen-forming fungi was discussed with emphasis on their potential to accelerate commercialization of lichen-based products., Conclusions: Lichens are an untapped source of biological activities of industrial importance and their potential is yet to be fully explored and utilized. Lichen-derived bioactive compounds hold great promise for biopharmaceutical applications as antimicrobial, antioxidant and cytotoxic agents and in the development of new formulations or technologies for the benefit of human life.

Introduction: Obesity is a real and dangerous problem with rising incidence. This study aimed to examine public perceptions of obesity as a disease, as well as the community's impression of the various modalities in the management of obesity, particularly bariatric surgery, in Singapore., Methods: Volunteers from the public were approached in 2010 to complete a questionnaire that collected both their demographic data and perceptions on obesity, management of obesity and bariatric surgery. The perceptions of the respondents were analysed based on various demographic factors., Results: The incidence of obesity was 16.8%. Consistent with previous studies in developed countries, the highest mean body mass index was noted in the age range of 41-50 years. 95.6% of the population surveyed were aware that obesity was related to significant medical conditions. 60% of the population surveyed had attempted weight loss in the past, with 41.7% expressing lack of success, and 58.4% expressed that they had not heard of surgery as a modality., Conclusion: This study shows that the majority of the population understands the significance of obesity as a medical problem and would take steps to combat it. However, there is suboptimal knowledge of the various modalities of managing obesity as a disease, especially with regard to surgical options. More education on the modalities available and access to them would help in the combat of this obesity epidemic.

Objective: Recent genome-wide association studies have identified a strong association between obesity and common variants in the fat mass and obesity associated (FTO) gene. FTO has been detected in the hypothalamus, but little is known about its regulation in that particular brain structure. The present study addressed the hypothesis that hypothalamic FTO expression is regulated by nutrients, specifically by glucose, and that its regulation by nutrients is impaired in obesity., Research Design and Methods: The effect of intraperitoneal (i.p.) or intracerebroventricular (i.c.v.) administration of glucose on hypothalamic Fto mRNA levels was examined in fasted mice. Additionally, the effect of glucose on Fto mRNA levels was also investigated ex vivo using mouse hypothalamic explants. Lastly, the effect of i.p. glucose injection on hypothalamic Fto immunoreactivity and food intake was compared between lean wild-type and obese ob/ob mice., Results: In wild-type mice, fasting reduced both Fto mRNA levels and the number of Fto-immunoreactive cells in the hypothalamus, whereas i.p. glucose treatment reversed this effect of fasting. Furthermore, i.c.v. glucose treatment also increased hypothalamic Fto mRNA levels in fasted mice. Incubation of hypothalamic explants at high glucose concentration increased Fto mRNA levels. In ob/ob mice, both fasting and i.p. glucose treatment failed to alter the number of Fto-immunoreactive cells in the hypothalamus. Glucose-induced feeding suppression was abolished in ob/ob mice., Conclusion: Reduction in hypothalamic Fto expression after fasting likely arises at least partly from reduced circulating glucose levels and/or reduced central action of glucose. Obesity is associated with impairments in glucose-mediated regulation of hypothalamic Fto expression and anorexia. Hypothalamic Fto-expressing neurons may have a role in the regulation of metabolism by monitoring metabolic states of the body.

A recently discovered thermophilic isolate, Geobacillus sp. R7, was shown to produce a thermostable cellulase with a high hydrolytic potential when grown on extrusion-pretreated agricultural residues such corn stover and prairie cord grass. At 70°C and 15-20% solids, the thermostable cellulase was able to partially liquefy solid biomass only after 36 h of hydrolysis time. The hydrolytic capabilities of Geobacillus sp. R7 cellulase were comparable to those of a commercial cellulase. Fermentation of the enzymatic hydrolyzates with Saccharomyces cerevisiae ATCC 24860 produced ethanol yields of 0.45-0.50 g ethanol/g glucose with more than 99% glucose utilization. It was further demonstrated that Geobacillus sp. R7 can ferment the lignocellulosic substrates to ethanol in a single step that could facilitate the development of a consolidated bioprocessing as an alternative approach for bioethanol production with outstanding potential for cost reductions.

The composition of thermophilic (60 degrees C) mixed cellulose-degrading enrichment culture initiated from compost samples was examined by constructing a 16S rRNA gene clone library and the presence of sequences related to Actinobacteria, Bacteroidetes, Chloroflexi, Deinococcus-Thermus, Firmicutes, and Proteobacteria were identified. Eight isolates capable of degrading cellulose, carboxymethyl cellulose (CMC), or ponderosa pine sawdust were identified as belonging to the genera Geobacillus, Thermobacillus, Cohnella, and Thermus. A compost isolate WSUCF1 (Geobacillus sp.) was selected based on its higher growth rate and cellulase activity compared to others in liquid minimal medium containing cellulose as a source of carbon and energy. Strain WSUCF1 and a previously isolated thermophilic cellulose-degrading deep gold mine strain DUSELR13 (Bacillus sp.) were examined for their enzyme properties and kinetics. The optimal pH for carboxymethyl cellulase (CMCase) activity was 5.0 for both isolates. The optimum temperatures for CMCase of WSUCFI and DUSELR13 were 70 and 75 degrees C, respectively. For CMC, the DUSELR13 and WSUCF1 CMCases had K(m) values of 3.11 and 1.08mg/ml, respectively. Most remarkably, WSUCF1 and DUSELR13 retained 89% and 78% of the initial CMCase activities, respectively, after incubation at 70 degrees C for 1day. These thermostable enzymes would facilitate development of more efficient and cost-effective forms of the simultaneous saccharification and fermentation process to convert lignocellulosic biomass into biofuels.

Background: Diabetic foot lesion is associated with increased morbidity and high resource use. Although early amputation has been advocated in case of osteomyelitis, conservative treatment is a more attractive alternative., Objective: To identify criteria predictive of failure of conservative treatment of diabetic foot ulcer at time of admission to the hospital., Methods: We conducted a 5-year retrospective cohort study with prospective long-term follow-up of all diabetic patients admitted for a foot lesion at a large (1600-bed) teaching institution. Predetermined criteria were used for the diagnosis and classification of diabetic foot lesions (Wagner classification). Study variables included patient demographics and clinical parameters related to infection and diabetes. The average follow-up after hospital discharge was 2 years. Failure of conservative treatment was the main outcome measure. Independent predictor variables were selected by logistic regression analysis., Results: A total of 120 diabetic patients were admitted for foot lesions; complications of contiguous osteomyelitis, deep tissue involvement, and/or gangrenous lesions occurred in 78 (74%) of the 105 patients for whom charts were available. Fourteen patients (13%) underwent immediate amputation. Conservative treatment was successful for 57 (63%) of the 91 remaining patients. Success was achieved in 21 (81%) of 26 patients presenting with skin ulcer, 35 (70%) of 50 patients with deep tissue infection or suspected osteomyelitis, and 1 (7%) of 15 patients with gangrene (P<.001, chi2 for trend). Independent factors predictive of failure were the presence of fever (odds ratio [OR]=1.1 per degrees Celcius; 95% confidence interval [CI], 1.0-1.2) and increased serum creatinine level (OR=1.002 per micromoles per liter; 95% CI, 1.0020-1.0021) on admission, prior hospitalization for diabetic foot lesion (OR=1.4; 95% CI, 1.2-1.6), and gangrenous lesion (OR=1.8; 95% CI, 1.5-2.2). Other patient characteristics, demographics, duration of diabetes mellitus, neutrophil count, or the anatomical site of the lesion failed to predict outcome., Conclusions: Conservative treatment, including prolonged, culture-guided parenteral and oral antibiotics, is successful without amputation in a large proportion of diabetic patients admitted for a foot skin ulcer or suspected osteomyelitis. Future studies comparing early amputation with novel therapeutic strategies for severe diabetic foot infection should take into account currently identified factors that predicted failure of conservative treatment on admission to the hospital.

Objective: To determine the relation of hamstring and quadriceps muscle strength and imbalance to hamstring injury using a prospective observational cohort study, Method: A total of 102 senior male Australian Rules footballers aged 22.2 (3.6) years were tested at the start of a football season. Maximum voluntary concentric and eccentric torque of the hamstring and quadriceps muscles of both legs was assessed using a Kin-Com isokinetic dynamometer at angular velocities of 60 and 180 degrees/second. Twelve (11.8%) players sustained clinically diagnosed hamstring strains which caused them to miss one or more matches over the ensuing season., Results: There were no significant differences for any of the isokinetic variables comparing the injured and non-injured legs in players with unilateral hamstring strains (n=9). Neither the injured nor the non-injured leg of injured players differed from the mean of left and right legs in non-injured players for any isokinetic variable. The hamstring to opposite hamstring ratios also did not differ between injured and non-injured players. A hamstring to opposite hamstring ratio of less than 0.90 and a hamstring to quadriceps ratio of less than 0.60 were not associated with an increased risk of hamstring injury. A significantly greater percentage of players who sustained a hamstring strain reported a history of hamstring strain compared with non-injured players (p=0.02). However, this was not related to muscle weakness or imbalance., Conclusions: Isokinetic muscle strength testing was not able to directly discriminate Australian Rules football players at risk for a hamstring injury.

Thirty-five patients with clinical features and histologically or microbiologically proven infection met predetermined stringent criteria for invasive aspergillosis over a 5-year period at our institution. Underlying conditions included hematologic malignancy, solid tumor, bone marrow and solid organ transplantation, and immunosuppressive therapy. The majority of patients (94%) presented with respiratory symptoms and abnormal pulmonary chest radiography; only 40% had neutropenia at time of infection. Invasive aspergillosis was suspected in only 21 cases (60%). Concomitant infections were present in 83% of patients. Half of patients had pathogenic or potentially pathogenic microorganisms other than Aspergillus spp. isolated from pulmonary specimens at time of aspergillosis. Aspergillus spp. were recovered from sputum in 75% of patients and from bronchoalveolar lavage in only 52%. Invasive aspergillosis is an unexpectedly unrecognized disease with poor outcome; overall mortality was 94% in our series. The lack of sensitivity of diagnostic procedures, together with the high frequency of concomitant infections, delays the time of diagnosis. Early diagnostic tests are needed, and presumptive antifungal therapy among high-risk patients is mandatory.

Foreign body implants are highly susceptible to microorganism infection. The infectious agents may be of low pathogenicity (such as S. epidermidis) or involve more virulent strains (such as S. aureus). The common denominator for the three main elements that play a role in the physiopathology of such infections (bacteria, neutrophils, and different biomaterials) are host proteins deposited over the surface of the devices immediately after their implantation. These proteins modulate that host cells response but can also promote Staphylococcus adhesion to the biomaterial. Neutrophils and other cells such as fibroblasts adhere to several extracellular matrix proteins such as fibronectin, fibrinogen, collagen, vitronectin, via specific cell surface receptor. The evolution of the technology and the increasing numbers of long-term artificial implants require a better understanding of fundamental mechanisms of foreign body infections to reduce their incidence and optimize their treatment.

SUMMARY. Myofascial trigger points (TPs) are sites in muscle or fascia which are tender to palpate and are located in a taut band of tissue. The significance of TPs is underlined by claims that treatment applied to TPs can be effective in treating pain. Before such claims can be validated, the ability of clinicians to identify these points reliably using palpation needs to be established. The location of such sites is also important for studies which try to determine the relationship of these points to other measures of pathology, e.g. EMG and thermographic abnormalities. Intertester reliability in the localization of these points, therefore, appears to be of primary importance. This study examined the concordance between two experienced clinicians in being able to identify TPs in the upper trapezius muscle. The results indicated that the agreement between these clinicians in identifying TPs in asymptomatic subjects was poor. There was a lack of concordance not only in the location of sites of TPs but also in the numbers of TPs identified. This outcome challenges claims that TPs can be reliably identified using palpation. Copyright 1997 Harcourt Publishers Ltd.

SUMMARY. The slump test has been used routinely to differentiate low back pain due to involvement of neural structures from low back pain attributable to other factors. It is also said to differentiate between posterior thigh pain due to neural involvement from that due to hamstring injury. If changes in cervical position affect the hamstring muscles, differential diagnosis is confounded. Posterior thigh pain caused by the cervical component of the slump could then be caused either by increased tension on neural structures or increased tension in the hamstrings themselves. The aim of this study was to determine whether changing the cervical position during slump altered posterior thigh pain and/or the tension in the hamstring muscle. Asymptomatic subjects aged between 18 and 30 years were tested. A special fixation device was engineered to fix the trunk, pelvis and lower limb. Pain levels in cervical flexion and extension were assessed by visual analogue scale. Fixation was successful in that there were no significant differences in position of the pelvis or knee during changes in cervical position. Averaged over the group, there was a 40% decrease (P < 0.05) in posterior thigh pain with cervical extension. There were no significant differences in hamstring electromyographic readings during the cervical movements. This indicated that: (1) cervical movement did not change hamstring muscle tension, and (2) the change in experimentally induced pain during cervical flexion was not due to changes in the hamstring muscle. This conclusion supports the view that posterior thigh pain caused by the slump test and relieved by cervical extension arises from neural structures rather than the hamstring muscle. Copyright 1997 Harcourt Publishers Ltd.

Objective: To provide quantitative data about the accuracy of the information about drugs presented to physicians by pharmaceutical sales representatives., Design: One hundred six statements about drugs made during 13 presentations by pharmaceutical representatives were analyzed for accuracy. Statements were rated inaccurate if they contradicted the 1993 Physicians' Desk Reference or material quoted or handed out by the sales representative., Setting: University teaching hospital., Results: Twelve (11%) of 106 statements about drugs were inaccurate. All 12 inaccurate statements were favorable toward the promoted drug, whereas 39 (49%) of 79 accurate statements were favorable (P = .005). None of 15 statements about competitors' drugs were favorable, but all were accurate, significantly P < .001) differing from statements about promoted drugs. In a survey of 27 physicians who attended these presentations, seven (26%) recalled any false statement made by a pharmaceutical representative, and 10 (37%) said information from the representatives influenced the way they prescribed drugs., Conclusions: Eleven percent of the statements made by pharmaceutical representatives about drugs contradicted information readily available to them. Physicians generally failed to recognize the inaccurate statements.

Two years' experience with an automated, point-of-use unit-dose system at the University of California, San Diego Medical Center (UCSDMC) is described. Growing concerns about the efficiency and cost-effectiveness of the traditional unit-dose drug distribution system at UCSDMC, and the corresponding diversion of professional staff time from pharmaceutical care responsibilities, led us to investigate alternative systems. Criteria for a new system were developed and used in evaluating alternatives. Consideration was given to three possibilities: 1) improving the existing system, 2) automating the unit-dose cassette fill process, or 3) automating the final step in medication delivery at the nursing station. Based on the realization that our traditional unit-dose system was largely inefficient in today's hospital environment, it was concluded that the drug distribution system needed to be re-engineered in a way that simplified delivery and reduced waiting time. The Medstation Rx system marketed by the Pyxis Corporation (San Diego, CA) seemed to meet the need. During a 2-year period a Medstation Rx system was implemented in most of the hospital (in all but three specialty units) and evaluated. This system has resulted in several benefits, including a net savings in labor costs, a significant reduction in waiting time for first doses, and a reduction in dispensing errors. In the process, it was possible to minimize the disruption of pharmacists engaged in the direct provision of pharmaceutical care, thereby increasing their efficiency.

Study Design: Fresh cadavers of five baboons were used to assess lumbar spinal cord movement. Window dissection at the L3 level was performed to observe the relative displacement of the cord to bony landmark, when the neck and hip were moved., Objectives: To examine the effect of the neck and hip flexion alone and in combination on the movements of the lumbar spinal cord relative to the third lumbar vertebral body. To investigate also the effect of the sequence of flexions., Summary of Background Data: Several clinical studies claim that cervical flexion together with straight leg raise tensions the lumbar nerve root. Although previous studies describe the effect of each of these movements, there have been no measurements of the combined effect or the effect of the sequence of movements., Methods: Five fresh baboon cadavers were dissected to expose the L3 nerve root. The movement of the lumbar cord at that level was measured relative to a pin on the L3 vertebra. The neck and leg of the cadavers were moved by two operators., Results: Cervical flexion always moved the lumbar cord in a cephalad direction. The degree of displacement was more pronounced if the cervical flexion followed hip flexion rather than hip extension. Hip flexion also moved the lumbar cord in a cephalad direction. However, the difference in cord displacement attributable to different sequences in hip movements were not found to be statistically significant. Cervical flexion elicited a greater cord displacement than traction., Conclusion: These findings would advocate that a test that comprises both neck and hip movements would be more sensitive in assessing nerve root movements than one that only uses neck or hip movements. Such a test should also consider the use of various sequences of neck and hip movements.

To study the role of cytosolic free calcium, [Ca2+]i, in cell activation, in particular during adhesion and movement on a surface in response to chemotactic peptide stimulation and during phagocytosis, we monitored [Ca2+]i in single human neutrophils. The neutrophils were loaded with fura-2 and allowed to adhere to albumin-coated glass coverslips. [Ca2+]i was monitored with a dual excitation microfluorimeter. Half of the cells showed spontaneous [Ca2+]i transients that lasted up to 15 min with an amplitude averaging 77 +/- 10 nM above basal levels (mean basal value of 110 +/- 20 nM) and a mean duration of 28 +/- 5 s. These repetitive [Ca2+]i elevations depended on the continuous presence of extracellular Ca2+ and could be dissociated from those triggered by the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (fMLP). Cell morphology was monitored in parallel by recording fluorescent images with a high sensitivity charge coupled device (CCD) camera. The majority of the cells studied showed visible changes in shape which started either before or at the same time as the onset of the [Ca2+]i transients. Removal of extracellular Ca2+ abolished [Ca2+]i transients without impairing cell movement and spreading. Blockade of adherence and cell movement with cytochalasin B markedly inhibited [Ca2+]i transients. Monoclonal antibodies directed against the leucocyte integrin CR3 (CD11b/CD18 alpha m beta 2) blocked adherence, spreading and most of the [Ca2+]i activity. Total [Ca2+]i activity was assessed during phagocytosis of C3bi-opsonized yeast particles and correlated with fusion of secondary granules with the phagosomal membrane (P-L fusion).(ABSTRACT TRUNCATED AT 250 WORDS)

To investigate the role of D-myo-inositol 1,3,4,5-tetrakisphosphate [Ins(1,3,4,5)P4] in the regulation of Ca2+ influx, we injected inositol phosphates into Xenopus oocytes and measured Ca(2+)-gated Cl- current to assay intracellular free Ca2+ concentration ([Ca2+]i). To assess Ca2+ influx, we removed extracellular Ca2+ or added the inorganic Ca2+ channel blocker Mn2+ to the extracellular bath and measured the resulting change in Cl- current. Ins(1,3,4,5)P4 did not cause Ca2+ influx when injected alone or when preceded by an injection of Ca2+. In contrast, Ins(1,3,4,5)P4 stimulated Ca2+ influx when injected after the poorly metabolized inositol trisphosphate (InsP3) analogues D-myo-inositol 1,4,5-trisphosphorothioate [Ins(1,4,5)P3S3] or D-myo-inositol 2,4,5-trisphosphate [Ins(2,4,5)P3]. These results indicate that Ins(1,3,4,5)P4 is not sufficient to stimulate Ca2+ influx but acts in synergy with InsP3s to cause Ca2+ influx. We also studied the effect of Ca2+ influx on the immediate metabolism of D-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] in single oocytes. Ca2+ influx shunted the metabolism of Ins(1,4,5)P3 toward the formation of Ins(1,3,4,5)P4 and away from D-myo-inositol 1,4-bisphosphate [Ins(1,4)P2]. These results suggest that there is a positive feedback regulatory mechanism in which Ca2+ influx stimulates Ins(1,3,4,5)P4 production and Ins(1,3,4,5)P4 stimulates further Ca2+ influx.

The effects of carbobenzyloxy-leucine-tyrosine-chloromethylketone (zLYCK), an inhibitor of chymotrypsin, were investigated on the activation pathways of the human neutrophil respiratory burst. At 10 microM zLYCK, a parallel inhibition was observed of superoxide production stimulated with the chemo-attractant FMLP and of chymotrypsin-like activity of human neutrophils. By contrast, superoxide production induced by PMA was minimally affected by zLYCK. The known transduction pathways triggered by FMLP were analyzed. zLYCK did not affect either the FMLP-induced cytosolic free calcium transient, inositol 1,4,5 trisphosphate formation, nor the PMA-induced phosphorylation of the 47-kDa substrate of protein kinase C. zLYCK did not affect the activity of protein kinase C extracted from neutrophils. In Ca(2+)-depleted cells, in which phosphatidylinositol 4,5-biphosphate breakdown does not occur, zLYCK inhibited the FMLP-induced respiratory burst in cells primed by low doses of PMA. The activity of the NADPH oxidase tested with active membranes from stimulated neutrophils or in a cell-free system was not inhibited by zLYCK. We conclude that: 1) zLYCK inhibits superoxide production through the inhibition of a chymotrypsin-like protease of the neutrophil, 2) zLYCK inhibits FMLP-induced activation of NADPH oxidase through a pathway independent of PtdInsP2 breakdown and cytosolic free calcium, and 3) zLYCK may prove a useful probe for the characterization of its target protease in neutrophil activation.

Numerous microbial factors are responsible for perioperative infections and influence the efficacy of antibiotic prophylaxis. These factors include the staphylococcal carrier state, bacterial adherence to a number of host proteins, the production of glycocalyx by sessile bacteria, and shifts in antibiotic resistance. A full understanding of the mechanisms involved will lead to further reductions in the number of postoperative infections. Unfortunately, the microbial factors affecting prophylaxis cannot be evaluated separately under clinical conditions; they are easier to study under circumstances whose bacteriologic features are well defined and in which the presence of foreign materials (e.g., sutures) greatly potentiates pathogenic mechanisms. Such circumstances exist, for example, in infections developing after "clean" surgery and in experimental models. Since even clean wounds are found to be contaminated when sampled carefully, the control of infection is more a quantitative than a qualitative problem. The critical period for the development of infection is short: an antibiotic course not exceeding 24 hours seems effective in preventing infection.

The effects of carbobenzyloxy-leucine-tyrosine-chloromethylketone (zLYCK), an inhibitor of chymotrypsin-like proteases, on signal transduction in human neutrophils triggered by the chemoattractant formyl-methionyl-leucyl-phenylalanine (fMLP) were investigated. zLYCK (10 microM) inhibited the fMLP-induced respiratory burst in neutrophils treated with cytochalasin B. In the presence of zLYCK (10 microM), the activation of phospholipase D in response to fMLP addition was inhibited. zLYCK did not inhibit the binding of [3H] fMLP to its receptor or the enzymic activity of phospholipase D because the response to ionomycin was unaffected. The effect of zLYCK on phospholipase D correlated well with its effects on the accumulation of diglycerides, which was also inhibited in the presence of zLYCK. In electropermeabilized neutrophils, too, zLYCK caused an inhibition of the fMLP-induced respiratory burst and the fMLP-induced activation of phospholipase D. Interestingly, this inhibition could be bypassed by guanosine 5'-O-(thiotriphosphate). We conclude that the inhibition of the respiratory burst in human neutrophils by zLYCK is caused by the selective inhibition of signal transduction leading to activation of phospholipase D and that zLYCK might be a useful probe to study the role of phospholipase D in neutrophil activation.

Substantial efforts have been devoted to improving the means for early and accurate diagnosis of ventilator-associated (VA) pneumonia in intensive care unit (ICU) patients because of its high incidence and mortality. A good diagnostic yield has been reported from quantitative cultures of bronchoalveolar lavage (BAL) fluid or a protected specimen brush, both obtained by fiberoptic bronchoscopy. As bronchoscopy requires specific skills and is costly, we evaluated a simpler method to obtain BAL fluid, that is, by a catheter introduced blindly into the bronchial tree. Quantitative cultures from bronchoscopically sampled BAL (B-BAL) and blindly nonbronchoscopically collected BAL (NB-BAL) were assessed for sensitivity, specificity, and predictive value for the diagnosis of VA pneumonia. A total of 40 pairs of samples were examined in 28 patients requiring prolonged mechanical ventilation and presenting a high risk of developing pneumonia. For comparison with bacteriologic data we defined a clinical score for pneumonia ranging from zero to 12 using the following variables: body temperature, leukocyte count, volume and character of tracheal secretions, arterial oxygenation, chest X-ray, Gram stain, and culture of tracheal aspirate. To quantify the bacteria in BAL the bacterial index (BI) was used, defined as the sum of the logarithm of the number of bacteria cultured per milliliter of BAL fluid. A good correlation between clinical score and quantitative bacteriology was observed (r = 0.84 for B-BAL and 0.76 for NB-BAL; p less than 0.0001). Similar to studies in baboons, patients with pulmonary infection could be distinguished by a BI greater than or equal to 5 with a sensitivity of 93% and a specificity of 100% (B-BAL).(ABSTRACT TRUNCATED AT 250 WORDS)

Multiple spontaneous transient elevations of cytosolic-free calcium ([Ca2+]i) are observed in single human neutrophils during adherence. The interrelation between adherence and spontaneous [Ca2+]i transients was analyzed by simultaneous monitoring of [Ca2+]i and cell morphology. Fluorescent images of fura 2-loaded neutrophils attached to albumin-coated glass were recorded with a high sensitivity CCD camera while [Ca2+]i was assessed with a dual excitation microfluorimetry. The majority of the initially round cells studied showed changes in shape which started either before or at the same time as the onset of the [Ca2+]i transients. These data suggested that a rise in [Ca2+]i is not a prerequisite for shape change. This conclusion was confirmed by observation of movement and spreading in cells whose [Ca2+]i transients were abolished by chelation of extracellular Ca2+. Instead, our data suggest that spreading or adhesion itself initiates the [Ca2+]i activity. In keeping with this hypothesis, cytochalasin B, which prevents both cell movement and adhesion, completely inhibited generation of [Ca2+]i transients. To determine if the movement alone or adhesion alone is responsible for [Ca2+]i activity, we treated cells with antibodies against the beta chain (CD18, beta 2) or the alpha subunit (CD11b, alpha m) of the dominant leukocyte integrin (CR3). Antibody-treated cells showed normal extension of pseudopods but impaired ability to adhere. Inhibition of adhesion in this way inhibited [Ca2+]i activity. Taken together these results suggest that following sequence of events after contact of neutrophils with surfaces: (a) cell movement and shape change lead to enhanced contact of integrins with the surface; and (b) integrins-mediated adhesion generates multiple [Ca2+]i transients. The [Ca2+]i transients may then control exocytic events associated with movement and may provide a link between adherence and activation or priming of neutrophils to other stimuli.

Bacterial adherence to surfaces is the determining first step in staphylococcal infections. Activated platelets mediate adherence of staphylococci to tissues during inflammation or infection; however, the molecular mechanisms of this interaction are not clearly understood. Thrombospondin, a large multifunctional glycoprotein, is the principal platelet-stored glycoprotein. It is secreted upon platelet activation and either bound to receptors on the platelet surface or released and incorporated into blood clots and extracellular matrices. To characterize thrombospondin binding to staphylococci, we incubated [125I]thrombospondin with Staphylococcus aureus Cowan 1 in the presence of albumin and separated bound and free thrombospondin by centrifugation. We found that binding was (i) specific, since it was up to 76% inhibitable and up to 60% reversible in the presence of a 100-fold excess of unlabeled thrombospondin, (ii) saturable, with an apparent dissociation constant (Kd) of 5.6 x 10(-9) M and a maximal number of 2,600 binding sites per microorganism, and (iii) Ca2+ dependent, since omission of this ion from the medium decreased significantly the binding capacity. The binding reaction was insensitive to previous trypsin treatment of bacteria, but it was strongly inhibited in the presence of heparin. Protein A-negative and -positive strains had similar binding characteristics. To determine the promotion of staphylococcal adherence to surfaces by solid-phase thrombospondin, we incubated 3H-labeled S. aureus Cowan 1 and 26 pathogenic staphylococcal isolates with thrombospondin-coated polymethylmethacrylate disks and found that adherence was significantly promoted as a function of adsorbed thrombospondin. These results indicate a role for thrombospondin as an important mediator of staphylococcal adherence to activated platelets, to blood clots, or to extracellular matrices in pyogenic infections.

Adherence, chemotaxis, phagocytosis, and responses to cytokines are mediated by distinct classes of cell surface receptors in human neutrophils. Intracellular signaling by these different receptors is a subject of active investigation. Observation of single neutrophils adherent to surfaces reveals the presence of spontaneous oscillations of cytosolic-free calcium, [Ca2+]i, generated by mechanisms that are presently unknown. Chemoattractant receptor activation via a specific G-regulatory protein activates a plasma membrane phospholipase C and generates diacylglycerol and inositol(1,4,5)triphosphate. DG activates C kinase(s). Ins(1,4,5)P3 releases Ca2+ from a specific intracellular organelle, the calciosome. Calciosomes resemble sarcoplasmic reticulum: they contain a Ca2(+)-ATPase and a high capacity/low affinity calcium-binding, calsequestrin-like protein. Chemoattractant receptor stimulation of calcium influx across the plasma membrane in phagocytes correlates strongly with the conversion of Ins(1,3,4,5)P3 to Ins(1,3,4,5)P4 by a Ca2(+)-calmodulin-sensitive kinase. The transduction system of phagocytosis receptors also generates DG and Ins(1,4,5)P3 and elicits [Ca2+]i elevations. The Ca2+ signal is an important regulator of secretion (granule exocytosis, superoxide production), whereas C kinase(s)/and other unknown mediators appear to be more important for the control of movement. Several mechanisms that could account for the specificity of cell signaling by different receptors are discussed.

A 50-year-old woman who developed acute endocarditis on a mitral Starr valve due to Neisseria subflava is reported. This microorganism, which belongs to the normal flora of the upper respiratory tract, is a very rare cause of endocarditis since only 9 cases have been described. The patient developed various complications including right hemiplegia. Cure was obtained by medical therapy alone due to the high susceptibility of the bacteria to a third generation cephalosporin (moxalactam). This is the third time a neurological complication of this kind is reported during N. subflava endocarditis. A high frequency of neurological and systemic embolic complications appears to be an important feature of endocarditis due to N. subflava and other saprophytic Neisseria.

Cytosolic free calcium and intracellular calcium stores were measured in neutrophils by trapping intracellularly the fluorescent calcium indicator Quin-2. Ten patients with untreated essential hypertension were compared to 10- age and sex-matched normotensive subjects. Intracellular calcium concentration and calcium stores did not differ in the two groups. No significant relationship was found between blood pressure and the calcium parameters. These results suggest that essential hypertension is not associated with a generalized cellular alteration in calcium handling.

The metabolism of [3H]inositol (1,4,5)-trisphosphate was followed in permeabilized bovine adrenal glomerulosa cells. At low Ca++ concentration (pCa = 7.2), more than 90% of [3H]inositol (1,4,5)-trisphosphate had disappeared within 2 min, while two other metabolites, [3H]inositol (1,3,4)-trisphosphate and [3H]inositol (1,3,4,5)-tetrakisphosphate appeared progressively. At higher Ca++ concentrations (pCa = 5.7 and 4.8), the formation of these two metabolites was markedly increased, but completely abolished if the medium was ATP-depleted. The peak levels for the generation of [3H]inositol (1,3,4,5)-tetrakisphosphate (1 min) preceded those of [3H]inositol (1,3,4)-trisphosphate and were closely correlated. These results suggest that, in adrenal glomerulosa cells, the isomer inositol (1,3,4)-trisphosphate is generated from inositol (1,4,5)-trisphosphate via a calcium-sensitive and ATP-dependent phosphorylation/dephosphorylation pathway involving the formation of inositol (1,3,4,5)-tetrakisphosphate.

The mechanism of neutrophil activation by the chemotactic peptide formyl-methionyl-leucyl-phenylalanine (FMLP) has been studied by pretreatment of human neutrophils with pertussis toxin. Upon stimulation with FMLP, the cytosolic-free calcium concentration, [Ca2+]i, is increased both by stimulation of calcium influx and mobilization of cellular calcium. We have measured [Ca2+]i as well as the generation of the phospholipid breakdown product inositol trisphosphate (IP3), which is thought to mediate Ca2+ mobilization. As the phosphoinositide pool in human neutrophils is difficult to prelabel with [3H]myoinositol, experiments were also carried out in the cultured human promyelocytic leukemia cell line HL-60 after differentiation with dimethylsulfoxide. Pertussis toxin pretreatment of both cell types inhibited FMLP stimulated membrane depolarization, exocytosis, and superoxide production in a dose-dependent manner. This toxin effect was selective for the receptor agonist, since stimulation of these parameters by two substances bypassing the transduction mechanism, the calcium ionophore ionomycin and the phorbolester phorbol myristate acetate, were unaffected. Rises in [Ca2+]i, as well as generation of IP3 in response to FMLP, were inhibited in parallel; for the inhibition of functional responses, slightly lower toxin concentrations were required. The attentuation of the [Ca2+]i rise was more marked in the absence of extracellular calcium, i.e., when the rise is due only to calcium mobilization. The results provide evidence that phospholipase C stimulation by FMLP resulting in IP3 generation is involved in the signal transduction mechanism. Coupling of FMLP receptor occupancy to phospholipase C activation is sensitive to pertussis toxin, suggesting the involvement of a GTP binding protein (N protein), which has been shown to be a pertussis toxin substrate. The parallel changes in [Ca2+]i and IP3 further support the hypothesis that IP3 is the calcium-mobilizing mediator in FMLP-activated cells.

Studies with fluorescent Ca2+ indicators in large populations of neutrophils in suspension reveal a stable base line followed by a rapid agonist-induced elevation of cytosolic free calcium, [Ca2+]i, concomitant with other parameters of cellular activation. To study the role of adhesion in cell activation, we monitored [Ca2+]i in single neutrophils adhered to albumin-coated or fibronectin-coated glass coverslips before and after stimulation with the chemotactic peptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP). Human neutrophils loaded with 2 microM fura 2/AM were allowed to adhere to coverslips for 15-20 min at 37 degrees C. [Ca2+]i was monitored with a dual excitation microfluorimeter with a time resolution of 200 ms. Statistical analysis was performed using an algorithm allowing to detect significant [Ca2+]i peaks. 54% of the cells showed spontaneous [Ca2+]i oscillations. The amplitude of these [Ca2+]i peaks averaged 77 +/- 10 nM above basal levels (mean value of 110 +/- 20 nM), and their mean duration was 28 +/- 5 s; periods of [Ca2+]i bursts could last up to 15 min. In "silent" cells exhibiting a stable [Ca2+]i base line without spontaneous oscillations, low concentrations of fMLP (10(-10)-10(-9) M) could induce sustained [Ca2+]i oscillations. By contrast, higher agonist concentrations (10(-6) M) induced a single [Ca2+]i transient followed by a stable base line. 47% of the cells showing spontaneous [Ca2+]i oscillations did not respond to fMLP. Spontaneous [Ca2+]i oscillations depended on the continuous presence of extracellular Ca2+. Therefore: (i) spontaneous oscillations of [Ca2+]i occur in neutrophils adherent to various substrata; (ii) these oscillations do not preclude and can be dissociated from the response to fMLP; (iii) neutrophil functions might be controlled by [Ca2+]i oscillations rather than by sustained alterations of [Ca2+]i.