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The impact of fine sediments on both habitat quality and macroinvertebrate communities of riverine systems has been well documented over recent years. However, there is a paucity of studies examining the mechanisms that relate macroinvertebrate sensitivity and responses of individual macroinvertebrate species to burial by sediment. Laboratory-based burial experiments were undertaken to study the response of some EPT species including Baetis rhodani, Ecdyonurus insignis, Rhithrogena semicolorata, Hydropsyche siltalai, Rhyacophila dorsalis and the amphipod Gammarus duebeni to burial. A range of burial conditions were studied which included five sediment fractions at two burial depths. Responses were variable across species and, overall, the ranking of the determinants that impacted on species responses to burial was burial depth > sediment class > species source, with no detectable effect linked to body size. Increased burial depth had the most marked effects on emergence times, while slower escape times were also observed from the finer sediment classes. Species source also influenced responses with some upland species taking longer or failing to emerge from burial. Further mechanistic studies, based on EPT species, are required to enhance our understanding of how and at what level sediment affect species, an essential step in developing pressure-specific biological metrics. [ABSTRACT FROM AUTHOR]

After approximately fifteen months of service, cracking was detected in the journal section of a 3-MW electric motor shaft used to drive a reciprocating gas compressor. A detailed failure analysis revealed sulfide inclusion and quench crack-initiated fatigue cracks. Two crack orientations were observed, axial and angular. The axial cracks are believed to be quench cracks which initiated along sulfide stringers; the angular cracks were found to be high-cycle fatigue cracks emanating from the axial cracks. Recommendations included the use of a reduced sulfur content shaft steel (0.010 wt.% max) and a pre-service non-destructive inspection to detect the presence of quench cracks or other surface imperfections. [ABSTRACT FROM AUTHOR]

We examined the systematic effects of display size on task performance as derived from a standard perceptual and cognitive test battery. Specifically, three experiments examined the influence of varying viewing conditions on response speed, response accuracy and subjective workload at four differing screen sizes under three different levels of time pressure. Results indicated a ubiquitous effect for time pressure on all facets of response while display size effects were contingent upon the nature of the viewing condition. Thus, performance decrement and workload elevation were evident only with the smallest display size under the two most restrictive levels of time pressure. This outcome generates a lower boundary threshold for display screen size for this order of task demand. Extrapolations to the design and implementation of all display sizes and forms of cognitive and psychomotor demand are considered. Practitioner Summary:This work specifies the effect of display size on operator performance. It presents a threshold for an acceptable level of response time and accuracy contingent upon time pressure imposed and display size presented. The procedure provides vital information for all future designers and users of displays. [ABSTRACT FROM AUTHOR]

Background Patients with cancer are often treated with glucocorticoids (GCs) as part of therapy, which may cause hyperglycemia. We sought to define the prevalence of, and risk factors for, hyperglycemia in this setting. Methods Adult patients taking GC as part of therapy protocols for primary brain tumour or metastasis, for lymphoma, or for bone marrow transplant (BMT) were screened with random glucometer measurements taken at least 3 hours after the last dose GCs. Results We screened 90 patients [44.4% women, 55.6% men; mean age: 59.6 years (range: 25-82 years); mean body mass index (BMT): 26.4 kg/m2 (range: 15.8-45.3 kg/m2)] receiving gc as part of cancer treatment. Mean total daily gc dose in the group was 238.5 mg (range: 30-1067 mg) hydrocortisone equivalents. Hyperglycemia (glucose ⩾ 8.0 mmol/L) was found in 58.9% (53 of 90), and diabetes mellitus (DM)-range hyperglycemia (glucose ⩾ 11.1 mmol/L) in 18.9% (17 of 90). The mean time from GC ingestion to glucometer testing was 5.5 hours (range: 3-20 hours). Presence of hyperglycemia did not correlate with traditional DM risk factors such as age, sex, BMT, and personal or family history of DM. A longer interval from GC dose to testing (p < 0.05), a higher GC dose (p = 0.04), and a shorter interval between the preceding meal and testing (p = 0.02) were risk factors for hyperglycemia in some patient groups. Conclusions Glucocorticoid-induced hyperglycemia is common in patients undergoing cancer treatment and cannot be predicted by traditional risk factors for DM. We recommend that all cancer patients receiving GC be screened for hyperglycemia at least 4-6 hours after GC administration. [ABSTRACT FROM AUTHOR]

In anaesthetised male rats an intravenous (i.v.) injection of p-chloroamphetamine (PCA) produced a specific patterned bursting response in the sympathetic vas deferens nerve (VDN) that corresponds to ejaculation. In the present, study selective dopamine agonists and antagonists were used to investigate whether dopaminergic mechanisms influence the generation of this ejaculatory-related response. Administration of a mixed D(1/2) receptor agonist (0.1-1.0 mg kg(-1) apomorphine i.v.) also evoked the characteristic bursting pattern responses in the VDN. Similar, but fewer, burst pattern responses could also be evoked by a selective D(2/3) receptor agonist (0.1-2.0 mg kg(-1) piribedil). Responses to 1.0 mg kg(-1) apomorphine were blocked by pretreatments with either 0.5 mg kg(-1) remoxipride (D(2) receptor antagonist) or 0.5 mg kg(-1) nafadotride (D(3) receptor antagonist), suggesting that D(2)-like receptors were involved. Responses could not be evoked by i.v. injections of apomorphine (1.0 mg kg(-1)) in anaesthetised male rats with a midthoracic spinal section, indicating that activation of D(2)-like receptors at supraspinal sites leads to an increase in the excitability of the lumbosacral pattern generator for ejaculation. In anaesthetised female rats a similar patterned bursting response occurred in the uterine nerve (UN) in response to apomorphine (0.5-2.0 mg kg(-1) i.v.). Thus a common neural mechanism may regulate sexual climactic reflexes in both sexes. [ABSTRACT FROM AUTHOR]

The incretins, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) are responsible for >50% of nutrient-stimulated insulin secretion. After being released into the circulation, GIP and GLP-1 are rapidly inactivated by the circulating enzyme dipeptidyl peptidase IV (DP IV). The use of DP IV inhibitors to enhance these insulinotropic hormonal axes has proven effective on an acute scale in both animals and humans; however, the long-term effects of these compounds have yet to be determined. Therefore, we carried out the following study: two groups of fa/fa Zucker rats (n = 6 each) were treated twice daily for 3 months with the DP IV inhibitor P32/98 (20 mg.kg(-1).day(-1), p.o.). Monthly oral glucose tolerance tests (OGTTs), performed after drug washout, revealed a progressive and sustained improvement in glucose tolerance in the treated animals. After 12 weeks of treatment, peak OGTT blood glucose values in the treated animals averaged 8.5 mmol/l less than in the controls (12.0 +/- 0.7 vs. 20.5 +/- 1.3 mmol/l, respectively). Concomitant insulin determinations showed an increased early-phase insulin response in the treated group (43% increase). Furthermore, in response to an 8.8 mmol/l glucose perfusion, pancreata from controls showed no increase in insulin secretion, whereas pancreata from treated animals exhibited a 3.2-fold rise in insulin secretion, indicating enhanced beta-cell glucose responsiveness. Also, both basal and insulin-stimulated glucose uptake were increased in soleus muscle strips from the treated group (by 20 and 50%, respectively), providing direct evidence for an improvement in peripheral insulin sensitivity. In summary, long-term DP IV inhibitor treatment was shown to cause sustained improvements in glucose tolerance, insulinemia, beta-cell glucose responsiveness, and peripheral insulin sensitivity, novel effects that provide further support for the use of DP IV inhibitors in the treatment of diabetes. [ABSTRACT FROM AUTHOR]

As-received and heat-treated Ti40Ta and Ti50Ta alloys were evaluated to determine their corrosion as well as mechanical performances and compared to Ti6A14V, a common material utilized for orthopedic (surgical) implants. Anodic potentiodynamic tests performed in PlasmalyteTM showed that all samples, except for the Ti50Ta specimen aged at 400 °C for 3 h gave a curve similar to that of Ti6A14V. Optical and TEM microscopy was performed to determine as-received and heat-treated microstructures. As-received materials showed an α precipitate in an α+β and martensite matrix. Samples that were aged at 400 °C increased in the density and the length of the α precipitate. Vickers hardness measurements were performed to get an approximation of the tensile strengths. Aged Ti40Ta and Ti50Ta specimens produced the highest tensile values when compared to the Ti6A14V material, representing a 31% and 56% increase for the 3 h samples and an 18% and 58% increase for the 10 h samples. Of all the materials studied the Ti50Ta specimen aged for 10 h exhibited the best biocompatibility showing excellent corrosion resistance combined with the highest tensile strength (1089 MPa and 58% harder/stronger than Ti6A14V). © 2001 Kluwer Academic Publishers [ABSTRACT FROM AUTHOR]

The management of malignant colonic polyps removed colonoscopically has been a controversial subject. A continuing series is reported of 36 patients with 37 malignant polyps removed by colonoscopic polypectomy (CP) between 1976 and 1982. Fourteen polyps contained carcinomain situ (CIS); 13 were treated by CP alone; one was treated by CP and colectomy. Nineteen polyps contained invasive carcinoma; 13 were treated by CP alone; six were treated by CP and colectomy. Four patients had sessile polyps resected piecemeal, in which accurate staging was impossible. Two were treated with CP alone, and two had CP plus colectomy. All patients were followed with yearly colonoscopy and/or barium enema. Follow-up has been six to 84 months (mean 36 months). Twenty-seven patients whose polyps were treated by CP alone have had no evidence of recurrent tumor at the polypectomy site. Of the nine patients undergoing colectomy, six had residual tumor at the polypectomy resection site. No patients had involved lymph nodes. Our current approach to this problem is based on the degree of invasion and the status of the resection margins. Polyps containing CIS can safely be treated with CP alone. Polyps with invasive carcinoma and clear resection margins should be treated with CP and either colectomy or frequent repeat colonoscopy. This decision is a clinical one and must involve input from both the clinician and the pathologist. Those polyps whose resection margins are involved or where piecemeal excision precludes accurate pathologic assessment should undergo colectomy. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined the assays used to diagnose acute pancreatitis. Patients and methods; Results and discussion.

A patient with acute intestinal obstruction due to unrecognized gastric phytobezoars is presented. There was no history of prior gastric or other abdominal surgery. At laparotomy several fragments of rubbery material were discovered obstructing the ileocecal valve. Exploration of the upper gastrointestinal tract revealed two partially fragmented bezoars in the stomach which were removed through a gastrotomy. After surgery the patient recounted the ingestion of persimmons a few weeks before the onset of her symptoms. A review of the literature reveals bezoars to be an infrequent, al-though not an altogether rare, cause of small bowel obstruction in patients without antecedent gastric surgery. A careful dietary history should accompany all patients presenting with acute intestinal obstruction. [ABSTRACT FROM AUTHOR]

PurposeTo investigate the role of silicone oil as an adjunct to iodine 125 (125I) brachytherapy in attenuating radiation dose and reducing radiation retinopathy.MethodsA 16-mm COMS plaque loaded with 125I seeds was simulated in vitro on an eye model containing silicone oil as a vitreous substitute using BrachyDose. The radiation dose ratio of silicone oil vs water to ocular structures was calculated at angles subtended from the centre of the eye. Silicone oil was then used in three choroidal melanoma patients who underwent 23-gauge vitrectomy, silicone oil placement, and 125I brachytherapy.ResultsSilicone oil reduced the ocular radiation dose in vitro to 65%. Radiation dose ratios on the retina increased from 0.45 to 0.99 when moving from points diametrically opposed to the plaque's central axis. In 10-24 months' follow-up, no patients have developed radiation retinopathy. Each patient required silicone oil removal and experienced cataract progression, and one also developed a retinal detachment.ConclusionsThis study confirms that silicone oil attenuates radiation dose in vitro, and may protect against radiation retinopathy clinically in patients, however it requires extensive surgical interventions. Further studies in only very selected populations using silicone oil as an adjunct to 125I brachytherapy will best elucidate its role in shielding radiation retinopathy. [ABSTRACT FROM AUTHOR]

Purpose: Stereotactic radiosurgery (SRS) is the primary treatment for most patients with cavernous sinus meningiomas. To analyze factors associated with tumor control and complications after single-fraction SRS, we reviewed patients having Gamma Knife SRS between 1990 and 2008. Methods: Excluded were patients with WHO grade II or III tumors, radiation-induced tumors, multiple meningiomas, Neurofibromatosis type 2, and prior or concurrent radiotherapy. Four patients were lost to follow-up and two patients refused research authorization. The remaining 119 patients (30 men/89 women) had either histologically confirmed WHO grade I tumors (n=48, 40%) or presumed (n=71, 60%) cavernous sinus meningiomas. The median prescription isodose volume was 9.4 cm3 (range, 1.3-42.2). The median margin dose was 16 Gy (range, 12-20); only 10 patients (8%) had tumor margin doses <14 Gy. The median follow-up after SRS was 85 months (range, 12-251). Thirty-seven patients (31%) had ≥10 years of follow-up after SRS. Results: Six patients (5%) had tumor progression (in-field, n=3; marginal, n=3) at a median of 74 months (range, 42-145) after SRS. The 5-year and 10-year tumor control rate was 99% and 93%, respectively. No analyzed factor was associated with tumor growth after SRS including previous surgery (HR=5.3, 95% CI 0.6- 45.8, P=0.12) or margin dose (HR=1.14, 95% CI 0.5- 1.48, P=0.64). Sixteen patients (14%) had permanent complications at a median onset of 23 months (range, 2-146) including trigeminal dysfunction (n=10), diplopia (n=3), ischemic stroke (n=2), and hypo-pituitarism (n=1). Multivariate analysis found increasing PIV (HR=1.07, 95% CI 1.02-1.13, P=0.006) to be associated with permanent complications after SRS. The complication rate for patients with a PIV = 9.4 cm3 was 3% (2/60) compared to 24% (14/59) for patients with a PIV > 9.4 cm3. No patient developed a radiation-induced tumor after SRS. Conclusions: Single-fraction SRS at the radiation doses used in this series provided durable tumor control for patients with benign cavernous sinus meningiomas. Despite the advances in SRS technique, tumor volume remains the primary factor associated with complications after single-fraction SRS of benign cavernous sinus meningiomas. Disclosure: No significant relationships. [ABSTRACT FROM AUTHOR]

Summary Background Intrapulmonary administration of IL-12 has been shown to inhibit the number of eosinophils in lung murine models of asthma, but the precise mechanism of this inhibition has not been reported. The purpose of this study was to examine whether IL-12 treatment inhibits bone marrow eosinophilopoiesis, and to elucidate the role of IFN-γ in this process. Objective To elucidate the in vivo and in vitro effects of IL-12 on eosinophil differentiation from murine bone marrow (BM) stem cells, and to examine the mechanistic role of IFN-γ in this process. Methods Allergen-sensitized BALB/c mice were administered low doses of intranasal IL-12 at the time of allergen challenge, and the number of eosinophils in BM was determined 3 days later. The direct actions of IL-12 on eosinophil differentiation from BM cells were determined in vitro . The mechanistic role of IFN-γ was assessed by measuring IFN-γ induction by IL-12 in BM cell cultures, and through the use of IFN-γ KO mice. Results Treatment of allergic mice with intrapulmonary IL-12 (1 ng or 10 ng) reduced eosinophils in BM by 43%. Culture of BM cells from allergen-sensitized mice with IL-3 + IL-5 induced eosinophil differentiation in vitro . Addition of IL-12 to these cultures inhibited eosinophil differentiation, with maximal inhibition (45%) occurring at 10 ng/mL IL-12 concentration. IL-12 induced IFN-γ production from BM cultures, and failed to inhibit eosinophil differentiation in IFN-γ-knockout mice, indicating a critical mechanistic role for IFN-γ. Conclusion This study demonstrates that IL-12 selectively inhibits BM eosinophilopoiesis, and that this effect is mediated by IFN-γ. Intrapulmonary IL-12 has suppressive effects on BM eosinophilopoiesis that may represent a novel mechanism contributing to the anti-eosinophilic effects of IL-12 in allergic airway disease. [ABSTRACT FROM AUTHOR]