Use of the Olympus endoArm for spinal and skull-based transsphenoidal neurosurgery

ManuscriptMinimally invasive surgical techniques have evolved to reduce soft-tissue injury associated with open surgical techniques. The use of endoscopic visualization allows the exposure of deep structures and provides a mechanism to perform all the components of an open surgical procedure through small portals, thus satisfying a basic requirement of minimally invasive surgical procedures. Surgeons in the field of skull-based and spine surgery are now taking advantage of the benefits of such endoscopes. The pneumatically powered EndoArm endoscopic holder has been used extensively in both cranial and spinal neurosurgical cases at the University of Utah. These cases include minimally invasive cervical and lumbar decompression procedures, as well as more recently for the resection of larger and more extensive pituitary tumors. In this paper, the multiple advantages of the Olympus EndoArm endoscopic holder are described in detail. As more surgeons gain experience with endoscopes in skull-based surgery, the hope is that operative times will be shorter and more extensive surgical resections will be possible with less patient morbidity

Effects of fostriecin on β2-adrenoceptor-driven responses in human mast cells

As part of the intracellular processes leading to mast cell and basophil activation, phosphorylation of key substrates is likely to be important. These processes, mediated by phosphatases, are responsible for regulating phosphorylation. The aim of the present study was to determine effects fostriecin – a selective inhibitor of PP2A (protein phosphatase-2) – on β2-adrenoceptor-driven responses in human mast cells. Here, the effects of fostriecin (PP inhibitors) on the inhibition of histamine release from HLMC, on β-adrenoceptor-driven responses in mast cells and on desensitization were investigated. Long-term incubation (24 h) of mast cells with fostriecin (10−6 M) resulted in a significant (p < 0.001) reduction in the maximal response (from 41.2 [± 3.0] to 29.9 [± 4.2] %) to salbutamol following fostriecin treatment. The results showed that fostriecin pretreatment significantly attenuated the inhibitory effects of salbutamol. Overall, the present study suggested that PP2A has an important role in regulating mast cell β2-adrenoceptors

A statistical approach to identify optimal inclusion criteria: An application to acute stroke clinical trials.

To develop a statistical approach that compares patient selection strategies across clinical trials and apply this approach to acute ischemic stroke clinical trials to identify the optimal inclusion criteria. We developed a statistical approach that compares the number needed to treat to achieve one success (NNT) along with the number needed to screen to achieve one success (NNS) and assesses if there are significant differences in inclusion criteria, treatment course, and clinical outcome among patients that may have been included/excluded in the trials. We applied this approach to the study population from four recent positive acute stroke clinical trials: MR CLEAN, EXTEND-IA, ESCAPE, and SWIFT PRIME, applying published trial criteria to an independent registry of 612 acute stroke patients, since we did not have access to the complete trial data. Although reported NNT were similar for EXTEND-IA, SWIFT PRIME and ESCAPE, and somewhat higher for MR CLEAN, NNS varied across the trials from 21 for EXTEND-IA, 27 for MR CLEAN, to 46 for ESCAPE and 64 for SWIFT PRIME, reflecting less and more stringent inclusion criteria, respectively. Although there were significant differences in imaging biomarkers and other clinical characteristics among patients that may have been included/excluded in the trials, these differences did not translate to significant differences in treatment course or clinical outcomes. Our study proposes a robust statistical approach that can be applied to a larger pooled trial dataset, if made available, to objectively compare across clinical trials and inform inclusion criteria of future trials. Pooled analysis of the acute stroke trial data is needed to determine which imaging biomarker inclusion criteria are critical and which may be relaxed. If this procedure were applied across the pooled trial data, it could decrease costs and refine the design of future trials to be the most efficacious for the greatest number of patients

Analyzing the failure and damage of FRP composite laminates under high strain rates considering visco-plasticity

In order to analyze composite structures under dynamic condition or model manufacturing processes in which high strain rates exist, it is important to develop a constitutive model that regards these effects. In this work, a phenomenological approach is used to formulate a continuum damage for composites in presence of high strain rates. Visco-plastic behavior of the composite is taken into account and the deformation of composite structures under dynamic conditions is studied. Effects of dynamic conditions on the material properties including strength and fracture toughness are included in the modeling. The model can capture the effects of strain rate on material behavior and has a good capability in the prediction of the response and final strength of composite laminates in comparison with the experimental data under medium and high rates

Stock assessment of zobaidy, Pampus argenteus, in the north of Persian Gulf

The project “Stock Assessment of Zobaidy, Pampus argenteus, in the North of Persian Gulf” started in April 2003 and completed by the end of April 2006 as a cooperative research project to assess the valuable stock of zobaidy shared between Kuwait and Iran in the North of Persian Gulf. The main objectives were to investigate and determine the basic biological parameters, the standing biomass, seasonal abundance, and the impact of regional fishery activities. These studies are necessary to recommend practical management policies and measures for long-term sustainability of the zobaidy stock. The sampling of fisheries data (catch, effort, fish length distributions, and biological data) was started in May 2003 and ended December 2006. Monthly length frequencies data were collected from both the drift gill net and shrimp trawl fisheries. Age determination was based on otolith sectioning, polishing, etching, and staining method. The age groups ranged from 0 to 10 yrs but the dominant age groups were 1-3 years and the estimated parameters for both sexes were L_∞ = 32.0-36.0 cm FL and K = 0.26-0.30 yr^-1, females grow faster than males. Sea survey on board of two dhow boats was carried out using swept area method. Higher abundance was always obtained in Kuwait Bay rather than the other areas surveyed in Kuwait and Khuzestan waters. The total estimated stock biomass in the surveyed areas varied from 42 t in January 2004 to 2,633 t in November 2004, while the Iranian biomass varied from as low as 19 t in October 2005 to 295 t in November 2003. The data indicated that Ras Al-Gaid, Bubiyan Island is the main nursery area in Kuwait waters, while Lifah, Busaif, and Bahrakan are important nursery areas in the Khuzestan waters. Kuwait Bay and Khor Musa are considered important spawning grounds and should be protected. Yield per recruit analysis showed that higher yield could be gained with increasing fish effort, which is not recommended under the present status of high exploitation rate. In contrast, virtual population analysis indicated that future catches will reduce if the fishery continues with present level fishing effort. A reduction of 50% would be required to maintain the present level of catches as well as to enhance the stock biomass. Formulation of a joint advisory management committee would be advisable approach to manage and monitor the zobaidy stock in the region. This will need commitment from the three countries in the region for data collection on regular basis on length frequency, statistics, and biological data. Copepods with high occurence of 64% - 88% is considered as the main item in the Pomfret fish, while jelly fish and other decapods crustaceans are considered as minor items. Observation of pre- flexion stage larvae of pampus genus among the specimens collected from Khuzestan coast water could be considered as an evidence for the spawning of this fish in this region. The occurrence of pampus larvae in Khuzestan coast during the months of June to October has been reported for several times. Examination of 101 specimens (38 from Kuwait, 63 from Iran) for molecular survey does not show any significant differences between Kuwait and Iran water stocks for this fish, so it is possible to hypothesize a unit population for zobidy stock in Persian Gulf and Oman Sea as whole

Could a defective epithelial sodium channel lead to bronchiectasis

<p>Abstract</p> <p>Background</p> <p>Bronchiectasis is defined as a permanent dilation of the airways arising from chronic bronchial inflammation/infection. In 50% of cases, no etiology can be identified. Recently, the role of the epithelial sodium channel ENaC has been pointed out in the pathophysiology of cystic fibrosis, a disease due to mutations in the <it>CFTR </it>gene and causing bronchiectasis in the airways. Moreover, it was found that transgenic mice overexpressing <it>ENaCβ </it>present cystic fibrosis-like lung disease symptoms. Our aim was to evaluate if a defective ENaC protein could be involved in the development of bronchiectasis.</p> <p>Methods</p> <p>We extensively analysed <it>ENaCβ </it>and <it>γ </it>genes in 55 patients with idiopathic bronchiectasis and without two mutations in the coding regions of <it>CFTR</it>. Thirty-eight patients presented functional abnormalities suggesting impaired sodium transport (abnormal sweat chloride concentration or nasal potential difference measurement), and 17 had no such evidence.</p> <p>Results</p> <p>Sequencing of the exons and flanking introns of the <it>ENaCβ </it>and <it>γ </it>gene identified five different amino-acid changes (p.Ser82Cys, p.Pro369Thr, p.Asn288Ser in <it>ENaCβ </it>; and p.Gly183Ser, p.Glu197Lys in <it>ENaCγ</it>) in heterozygous state in 8 patients. The p.Ser82Cys amino-acid change was found in 3 unrelated patients who were also heterozygous for a <it>CFTR </it>mutation or variant (1 p.F508del, 1 IVS8-5T, and 1 IVS8-5T:1716G>A (p.E528E)). The other mutations were found in patients without <it>CFTR </it>mutation, the p.Glu197Lys mutation in 2 patients and the other variants in single patients. Among the 8 patients bearing an <it>ENaC </it>mutation, 5 had functional abnormalities suggesting impaired sodium transport.</p> <p>Conclusion</p> <p>Our results suggest that several variants in <it>ENaCβ </it>and <it>γ </it>genes might be deleterious for ENaC function and lead to bronchiectasis, especially in patients who are trans-heterozygotes for <it>ENaCβ/CFTR </it>mutations or variants.</p