487 research outputs found
Determination of Pancreatic and Salivary Amylase By Enzyme Immunoassay and Their Prevalence in Hyperamylasemic Patients
Currently, amylase determinations are nonspecific for the organ source and are based entirely on the enzymatic properties of amylase to produce a measurable product or byproduct. The determination of pancreatic amylase is important in the diagnosis of acute pancreatitis. Most commercially available tests for amylase employ the measurement of the change in NADH absorbance at 280 nm or of the p-nitrophenol released from a maltotetrose substrate. These are nonspecific measurements of pancreatic amylase and often necessitate other tests to be run such as a serum lipase.
The two predominant isoenzymes of amylase are pancreatic (p-amylase) and salivary (s-amylase); the most important of which is pancreatic. Pancreatic amylase to date is determined by the removal of salivary amylase by monoclonal antibody, wheat germ, or ion-exchange chromatography. Also amylase isoenzymes are determined by electrophoresis. These methods are time consuming and lack either specificity or quantification capability. There is a 7% difference in the amino acid sequences of pancreatic and salivary amylase. These structural differences between pancreatic and salivary amylase are small but significant enough that they should enable a monoclonal antibody to be produced for each isoenzyme.
A sensitive and specific microwell assay based on sandwich technique for the quantitative determination of the p-amylase and s-amylase was developed. Microwells were utilized for the solid-phase immobilization of the amylase inhibitor cycloheptaamylose (CHA) which was coupled to bovine serum albumin (BSA) by carbodiimide coupling. Monoclonal antibodies were produced against p-amylase and s-amylase (PAb and SAb). These were purified by Protein-A affinity chromatography and then coupled to horseradish peroxidase (HRPO) by carbodiimide coupling. The microwells which were coated with oxidized CHA-BSA (CHA-BSA) were incubated with patient\u27s serum and then allowed to react with the PAb-HRPO and SAb-HRPO.
This EIA method is able to distinguish between p-amylase and s-amylase quantitatively, rapidly and has the capability for automation. The correlation coefficients for human serum samples were 0.920 and 0.867 for p-amylase and s-amylase when comparing this EIA method and protein electrophoresis then staining for amylase. The limit of detection was determined to be 8 U/L for p-amylase and 16 U/L for s-amylase. The percent coefficient of variation for p-amylase was found to be 7.79% for the normal control and 6.28% for the abnormal control. The percent coefficient of variation for s-amylase was found to be 9.42% for the normal control and 9.29% for the abnormal control
Cultural Resource Assessment and Archival Research for the Proposed Galveston-Bolivar Causeway Galveston County, Texas
In 2008, following a cultural resources remote-sensing survey for the Proposed Galveston-Bolivar Causeway Project, PBS&J was contracted by the Texas Department of Transportation to perform three studies as supplements to the original investigation. These studies comprised a hydraulic probing investigation at the Old Port Bolivar slip in the area of a charted historic shipwreck; a review of historic maps and aerial photography of the Area of Potential Effect (APE); and an assessment of a collection of abandoned hulks at the northwestern tip of Bolivar Peninsula. All three studies were completed between June and August 2008.
The hydraulic probing investigation at the Old Port Bolivar slip located the remains of a potential submerged shipwreck site measuring approximately 40 x 11 feet at a depth of 17–18 feet below the water surface. PBS&J also examined over 40 historic maps from the collections of the National Archives in Washington, D.C. The investigation of historic maps isolated at least 12 shipwrecks within the APE. Historic Tobin aerial photos of the APE acquired by PBS&J were limited to the sets available from 1930 and 1956. One shipwreck anomaly discovered during the 2007 Galveston-Bolivar Causeway remote-sensing survey was captured in the 1956 aerial. The incomplete coverage area of the 1930 photography prevented a review of other known targets. An investigation of the abandoned hulks at Bolivar Peninsula determined that 16 barges are arranged in three primary groups. These barges have either ferrous or wooden hulls; most of the hulks are submerged. Research did not discover parallels for the types of barges examined by PBS&J, but review of barge construction history indicates many of these hulks could likely predate World War II
Chasing the Phantom Ship: Revisiting Interpretations of the Boca Chica No. 2 Shipwreck on the Texas Coast
Boca Chica Beach spans the south Texas coast in Cameron County for a distance of roughly 12 kilometers between Brazos Santiago Pass and the mouth of the Rio Grande River at the Texas and Mexican border. More than 165 historic ships have been reported lost along the south Texas coast in this general area and at least four, or portions thereof, have been discovered so far. The most well-known of the shipwreck remains is archeological site 41CF184, nicknamed Boca Chica No. 2, which has gained almost mythological status in the region as it has long been circumstantially linked to the Mexican warship Moctezuma; not-so-coincidentally one of the most famous shipwrecks in the region. Is Boca Chica No. 2 the famous warship, once believed to be a “phantom” because it so often eluded the Texian patrols? Evidence suggests otherwise but the significance of both the historic ship and the archeological site invite reexamination of this unresolved mystery
Chasing the Phantom Ship: Revisiting Interpretations of the Boca Chica No. 2 Shipwreck on the Texas Coast
Boca Chica Beach spans the south Texas coast in Cameron County for a distance of roughly 12 kilometers between Brazos Santiago Pass and the mouth of the Rio Grande River at the Texas and Mexican border. More than 165 historic ships have been reported lost along the south Texas coast in this general area and at least four, or portions thereof, have been discovered so far. The most well-known of the shipwreck remains is archeological site 41CF184, nicknamed Boca Chica No. 2, which has gained almost mythological status in the region as it has long been circumstantially linked to the Mexican warship Moctezuma; not-so-coincidentally one of the most famous shipwrecks in the region. Is Boca Chica No. 2 the famous warship, once believed to be a “phantom” because it so often eluded the Texian patrols? Evidence suggests otherwise but the significance of both the historic ship and the archeological site invite reexamination of this unresolved mystery
Chitosan nanoparticle-based neuronal membrane sealing and neuroprotection following acrolein-induced cell injury
<p>Abstract</p> <p>Background</p> <p>The highly reactive aldehyde acrolein is a very potent endogenous toxin with a long half-life. Acrolein is produced within cells after insult, and is a central player in slow and progressive "secondary injury" cascades. Indeed, acrolein-biomolecule complexes formed by cross-linking with proteins and DNA are associated with a number of pathologies, especially central nervous system (CNS) trauma and neurodegenerative diseases. Hydralazine is capable of inhibiting or reducing acrolein-induced damage. However, since hydralazine's principle activity is to reduce blood pressure as a common anti-hypertension drug, the possible problems encountered when applied to hypotensive trauma victims have led us to explore alternative approaches. This study aims to evaluate such an alternative - a chitosan nanoparticle-based therapeutic system.</p> <p>Results</p> <p>Hydralazine-loaded chitosan nanoparticles were prepared using different types of polyanions and characterized for particle size, morphology, zeta potential value, and the efficiency of hydralazine entrapment and release. Hydralazine-loaded chitosan nanoparticles ranged in size from 300 nm to 350 nm in diameter, and with a tunable, or adjustable, surface charge.</p> <p>Conclusions</p> <p>We evaluated the utility of chitosan nanoparticles with an in-vitro model of acrolein-mediated cell injury using PC -12 cells. The particles effectively, and statistically, reduced damage to membrane integrity, secondary oxidative stress, and lipid peroxidation. This study suggests that a chitosan nanoparticle-based therapy to interfere with "secondary" injury may be possible.</p
Recommended from our members
Chronic Acceleration and Osteogenesis
The effect of excess gravity on bone-forming elements of the growing perichondrial shaft of embryonic chicks was investigated through the use of the transmission electron microscope and various cytochemical techniques
Behavioral recovery from traumatic brain injury after membrane reconstruction using polyethylene glycol
Polyethylene glycol (PEG; 2000 MW, 30% by volume) has been shown to mechanically repair damaged cellular membranes and reduce secondary axotomy after traumatic brain and spinal cord injury (TBI and SCI respectively). This repair is achieved following spontaneous reassembly of cell membranes made possible by the action of targeted hydrophilic polymers which first seal the compromised portion of the plasmalemma, and secondarily, allow the lipidic core of the compromised membranes to resolve into each other. Here we compared PEG-treated to untreated rats using a computer-managed open-field behavioral test subsequent to a standardized brain injury. Animals were evaluated after a 2-, 4-, and 6-hour delay in treatment after TBI. Treated animals receive a single subcutaneous injection of PEG. When treated within 2 hours of the injury, injured PEG-treated rats showed statistically significant improvement in their exploratory behavior recorded in the activity box when compared to untreated but brain-injured controls. A delay of 4 hours reduced this level of achievement, but a statistically significant improvement due to PEG injection was still clearly evident in most outcome measures compared at the various evaluation times. A further delay of 2 more hours, however, eradicated the beneficial effects of PEG injection as revealed using this behavioral assessment. Thus, there appears to be a critical window of time in which PEG administration after TBI can provide neuroprotection resulting in an enhanced functional recovery. As is often seen in clinically applied acute treatments for trauma, the earlier the intervention can be applied, the better the outcome
Analysis of the Pass Cavallo shipwreck assemblage, Matagorda Bay, Texas
A survey conducted in February of 1998 located an anomaly originally believed to be the remains of L'Aimable. L'Aimable was one of four ships utilized by Rene-Robert Cavelier, Sieur de La Salle, for his voyage to colonize the Gulf Coast in 1684. The anomaly, a wrecked vessel with a heavy iron signature, was located outside the entrance to the historic pass into Matagorda Bay, Texas. Artifacts were extracted from the wreck site to aid in the identification of the vessel, which was subsequently determined to be more recent in origin. A preliminary examination of the artifacts indicates that the shipwreck dates to the first half of the 19th century.
The survey recovered over two hundred artifacts. The assemblage of artifacts includes over 80 lead shot, over 40 examples of brass firearm furniture, over 15 firearm fragments, several pieces of copper sheathing, and iron bar stock. Almost two-thirds of the material is associated with small arms. The majority of the identifiable firearms are military arms of three patterns: the British Short Land Pattern, the British India Pattern, and the 1757 Spanish musket.
Historical research has determined that these arms were circulating in Texas, New Orleans, and Mexico, as early as 1815. The British Pattern arms were both purchased for the Mexican army in the 1820s, and used by the British Infantry in the Battle of New Orleans in 1815. The 1757 Spanish musket was used chiefly by Spanish expeditionary forces in North America in the late 18th century.
Evidence garnered from the artifacts suggest that the firearms were shipboard cargo onboard a small, wood-hulled sailing vessel that wrecked between the years 1815 and 1845. Archival and historical research isolated nine wreck candidates for this period. Historical research and artifact analysis suggest the Hannah Elizabeth as the primary candidate for this wreck site. The Hannah Elizabeth was a small merchant schooner from New Orleans laden with a munitions cargo for Texas troops stationed at Goliad. The vessel wrecked at the entrance of the historic Pass Cavallo while evading capture from a Mexican brig-of-war in November of 1835
Investigation and Recovery of USS Westfield (Site 41GV151) Galveston Bay, Galveston County, Texas
This report represents the culmination of fourteen years of marine archeological investigations by PBS&J (now Atkins North America, Inc.) associated with the Texas City Channel Improvement Project. Over that time span Atkins’ investigations of the site of USS Westfield (41GV151) have included numerous remote-sensing surveys using various combinations of marine magnetometer, side-scan sonar, sector-scan sonar, sub-bottom profiler, and ROV; three diving investigations totaling 64 dives and over 72 hours of bottom time; and archeological salvage of Westfield resulting in the recovery of at least 8,380 artifacts. These combined efforts were undertaken in order to satisfy the responsibilities of the U.S. Army Corps of Engineers under Section 106 of the National Historic Preservation Act (Public Law 89-665; 16 U.S.C. 470) and the Antiquities Code of Texas (Texas Natural Resource Code, Title 9, Chapter 191). The archeological investigations reported in this document were conducted under Texas Antiquities Permits 3878, 4622, and 5271, issued by the Texas Historical Commission, and Federal Permits for Intrusive Archaeological Research on U.S. Naval Cultural Resources, Nos. PBSJ-2009-001 and PBSJ2009-0002, issued by the U.S. Naval History and Heritage Command. The minimum reporting and survey requirements for marine archeological studies conducted under a Texas Antiquities Permit are mandated by The Texas Administrative Code, Title 13, Part 2, Chapters 26 and 28, respectively. The results of six separate site investigations are reported in this document, including Contract DACW64-03-D-0001Delivery Orders 0004 and 0005, conducted in 2005 and 2006, respectively, and additional site assessments and data recovery conducted under Delivery Order 0006 and four subsequent delivery order modifications in 2007, 2009, and 2010. The results of Delivery Order 0004 conclusively demonstrated that the source of recorded anomaly GV0031 was a shipwreck (and given the site designation 41GV151), which tentatively matched the time period and characteristics of Westfield. The results of Delivery Order 0005 further substantiated the identity of 41GV151 as USS Westfield and concluded that the site demonstrates several criteria for eligibility to the National Register of Historic Places. Delivery Order 0006 resulted in the data recovery operations, which are the primary focus of this report
Ecologia de saberes na formação de professores de lĂngua: o uso das novas tecnologias nas zonas de contato entre ensino básico e superior
The attacks against Brazilian education are not a recent phenomenon, but lately criticism against primary and higher education and their depreciation have made education an easy target for social criticism. Knowledge produced in public basic education, on the one hand, is considered inefficient or deficient. On the other hand, the university is losing its legitimacy because of the lack of circulation of the knowledge it produces (SOUSA SANTOS, 2011). This qualitative ethnographic research seeks to discuss the development of new pedagogies, new processes of construction and diffusion of scientific and lay knowledges, and new social commitments, on local, national and global levels, by creating contact zones (PRATT, 1992) between basic and higher education. The exchange of knowledges on English language teaching, of this denationalized and de-territorialized language (RAJAGOPALAN, 2004, p. 2004), turns the space where knowledges meet into a dynamic and rich place. Thus, we observe the need to make a critique of traditional schooling that does not incorporate new technologies that are part of the world of our students, regardless of the social class that each one of them belongs to. Digital inclusion in the educational system should lead to new forms of language learning and teaching and make educators and educated people not only consumers of digital ways of meaning-making, but also producers (PARDO, 2015).NĂŁo Ă© de hoje que a educação brasileira sofre ataques, mas ultimamente as crĂticas contra o ensino básico e superior pĂşblico e a sua depreciação tornaram a educação alvo fácil da crĂtica social. O conhecimento produzido no ensino básico pĂşblico, por um lado, Ă© considerado ineficiente ou deficiente. Do outro lado, a universidade está perdendo sua legitimidade por causa da falta de circulação dos conhecimentos produzidos por ela (SANTOS, 2011). Essa pesquisa qualitativa de cunho etnográfico busca desenvolver novas pedagogias, novos processos de construção e de difusĂŁo de conhecimentos cientĂficos e leigos, e novos compromissos sociais, locais, nacionais e globais a partir de criação de zonas de contato (PRATT, 1992) entre a educação básica e superior. A troca de saberes sobre o ensino de lĂngua inglesa, essa lĂngua desnacionalizada e desterritorializada (RAJAGOPALAN, 2004, p. 2004), torna o espaço de encontro de saberes em lugar dinâmico e rico. Assim, vemos a necessidade de fazer uma crĂtica ao ensino tradicional que nĂŁo incorpora as novas tecnologias que fazem parte do mundo do nosso alunado sem relação Ă classe social que cada um pertence. A inclusĂŁo digital no sistema educacional deve levar a novas formas de aprendizagem e de ensino de lĂnguas e tornar os educadores e os educandos nĂŁo sĂł consumidores das formas digitais de criar sentidos, mas tambĂ©m produtores
- …