Purification of a chymotrypsin-like enzyme present on adult Schistosoma mansoni worms from infected mice and its characterization as a host carboxylesterase

A serine protease-like enzyme found in detergent extracts of Schistosoma mansoni adult worms perfused from infected mice has been purified from mouse blood and further characterized. The enzyme is approximately 85 kDa and hydrolyses N-acetyl-DL-phenylalanine β-naphthyl–ester, a chromogenic substrate for chymotrypsin-like enzymes. The enzyme from S. mansoni worms appears to be antigenically and enzymatically similar to a molecule that is present in normal mouse blood and so is seemingly host-derived. The enzyme was partially purified by depleting normal mouse serum of albumin using sodium chloride and cold ethanol, followed by repeated rounds of purification by one-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis. The purified material was subjected to tandem mass spectrometry and its derived peptides found to belong to mouse carboxylesterase 1C. Its ability to hydrolyse α- or β-naphthyl acetates, which are general esterase substrates, has been confirmed. A similar carboxylesterase was purified and characterized from rat blood. Additional evidence to support identification of the enzyme as a carboxylesterase has been provided. Possible roles of the enzyme in the mouse host–parasite relationship could be to ease the passage of worms through the host's blood vessels and/or in immune evasion

Professional identity, career commitment, and career entrenchment of midlevel student affairs professionals

The purposes of this study were to identify factors of midlevel student affairs administrators’ professional identity and to examine the association of those factors to career commitment, career entrenchment, and demographic characteristics. Principal axis factor analysis derived 3 dimensions of professional identity: career contentment, community connection, and values congruence with the profession. Regression analyses conducted on 377 survey responses revealed that 3 of 4 demographic characteristics, all 3 career commitment subscales, and all 3 career entrenchment subscales were significantly associated with at least 1 of the professional identity subscales. Implications for research and practice are discussed

Socialization to student affairs: Early career experiences associated with professional identity development

In this study, the authors propose and test a model of professional identity development among early career student affairs professionals. Using survey data from 173 new professionals (0-5 years of experience), factor analysis revealed three dimensions of professional identity: commitment, values congruence, and intellectual investment. Multivariate analyses found significant associations of age, master’s program characteristics, and influential people and experiences (e.g., interactions with professional colleagues and associations) with the dimensions of professional identity. Findings indicated key socialization experiences during and after graduate school were associated with the development of professional identity. We conclude with recommendations for practice and research

Development of Professional Identity Through Socialization in Graduate School

Professional identity is one outcome of successful socialization. The purpose of this study was to understand how socialization in graduate programs contributes to the development of professional identity for new professionals in student affairs. Via survey, we found significant relationships between program qualities, standards, activities, and experiences and measures of professional identity. Out-of-class experiences were perceived to have a strong influence than in-class experiences. Implications for graduate preparation programs and supervisors are discussed

Prolongation of isovolumetric relaxation time as assessed by Doppler echocardiography predicts doxorubicin-induced systolic dysfunction in humans

AbstractA reasonably sensitive and specific noninvasive test for doxorubicin cardiotoxicity is needed. In addition, few data exist on the short- and long-term effects of doxorubicin on diastolic filling. To determine if pulsed Doppler indexes of diastolic filling could predict doxorubicin-induced systolic dysfunction, 26 patients (mean age 48 ± 12 years) were prospectively studied before receiving chemotherapy (control) and 3 weeks after obtaining cumulative doses of doxorubicin.In nine patients developing doxorubicin-induced systolic dysfunction (that is, a decrease in ejection fraction by ≥ 10 ejection fraction units to <55% the isovolumetric relaxation time was prolonged (from 66 ± 18 to 84 ± 24 ms, p < 0.05) after a cumulative doxorubicin dose of 100 to 120 mg/m2. This prolongation preceded a significant decrease in ejection fraction. Other Doppler indexes of filling were impaired after doxorubicin therapy but occurred simultaneously with the decrease in ejection fraction.A >37% increase in isovolumetric relaxation time was 78% (7 of 9) sensitive and 88% (15 of 17) specific for predicting the ultimate development of doxorubicin-induced systolic dysfunction. In 15 patients studied 1 h after the first treatment, doxorubicin enhanced Doppler indexes of filling and shortened isovolumetric relaxation time. In 22 patients, indexes of filling remained impaired and isovolumetric relaxation time was prolonged 3 months after the last doxorubicin dose.In conclusion, doxorubicin-induced systolic dysfunction is reliably predicted by prolongation of Doppler-derived isovolumetric relaxation time. Early after administration, doxorubicin enhances filling and isovolumetric relaxation time. The adverse effects of doxorubicin on both variables persist at least 3 months after cessation of treatment

METHANE HYDRATE PRODUCTION FROM ALASKAN PERMAFROST

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrate potential agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is a cost-shared partnership between Maurer Technology, Anadarko Petroleum, Noble Corporation, and the U.S. Department of Energy's Methane Hydrate R&amp;D program. The purpose of the project is to build on previous and ongoing R&amp;D in the area of onshore hydrate deposition to help identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. As part of the project work scope, team members drilled and cored a well (the Hot Ice No. 1) on Anadarko leases beginning in January 2003 and completed in March 2004. Due to scheduling constraints imposed by the Arctic drilling season, operations at the site were suspended between April 21, 2003 and January 30, 2004. An on-site core analysis laboratory was constructed and used for determining physical characteristics of frozen core immediately after it was retrieved from the well. The well was drilled from a new and innovative Anadarko Arctic Platform that has a greatly reduced footprint and environmental impact. Final efforts of the project were to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists for future hydrate operations. No gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in the project reports. Documenting the results of this effort are key to extracting lessons learned and maximizing the industry's benefits for future hydrate exploitation

Methane Hydrate Production From Alaskan Permafrost: Final Report

Natural-gas hydrates have been encountered beneath the permafrost and considered a nuisance by the oil and gas industry for years. Oil-field engineers working in Russia, Canada and the USA have documented numerous drilling problems, including kicks and uncontrolled gas releases, in Arctic regions. Information has been generated in laboratory studies pertaining to the extent, volume, chemistry and phase behavior of gas hydrates. Scientists studying hydrates agree that the potential is great--on the North Slope of Alaska alone, it has been estimated at 590 TCF. However, little information has been obtained on physical samples taken from actual rock containing hydrates. This gas-hydrate project is a cost-shared partnership between Maurer Technology, Anadarko Petroleum, Noble Corporation, and the U.S. Department of Energy's Methane Hydrate R&amp;D program. The purpose of the project is to build on previous and ongoing R&amp;D in the area of onshore hydrate deposition to help identify, quantify and predict production potential for hydrates located on the North Slope of Alaska. As part of the project work scope, team members drilled and cored the HOT ICE No. 1 on Anadarko leases beginning in January 2003 and completed in March 2004. Due to scheduling constraints imposed by the Arctic drilling season, operations at the site were suspended between April 21, 2003 and January 30, 2004. An on-site core analysis laboratory was designed, constructed and used for determining physical characteristics of frozen core immediately after it was retrieved from the well. The well was drilled from a new and innovative Anadarko Arctic Platform that has a greatly reduced footprint and environmental impact. Final efforts of the project were to correlate geology, geophysics, logs, and drilling and production data and provide this information to scientists for future hydrate operations. Unfortunately, no gas hydrates were encountered in this well; however, a wealth of information was generated and is contained in the project reports

Molecular determinants of a competent bovine corpus luteum: first vs final wave dominant follicles

Reproductive management in cattle requires the synchrony of follicle development and oestrus before insemination. However, ovulation of follicles that have not undergone normal physiological maturation can lead to suboptimal luteal function. Here, we investigated the expression of a targeted set of 47 genes in (a) a first-wave vs final-wave dominant follicle (DF; the latter destined to ovulate spontaneously) and (b) 6-day-old corpora lutea (CLs) following either spontaneous ovulation or induced ovulation of a first-wave DF to ascertain their functional significance for competent CL development. Both the mass and progesterone-synthesising capacity of a CL formed following induced ovulation of a first-wave DF were impaired. These impaired CLs had reduced expression of steroidogenic enzymes (e.g. STAR and HSD3B1), luteotrophic receptors (LHCGR) and angiogenic regulators (e.g. VEGFA) and increased expression of BMP2 (linked to luteolysis). Relative to final-wave DFs, characteristic features of first-wave DFs included reduced oestradiol concentrations and a reduced oestradiol:progesterone ratio in the face of increased expression of key steroidogenic enzymes (i.e. CYP11A1, HSD3B1 and CYP19A1) in granulosa cells and reduced expression of the HDL receptor SCARB1 in thecal cells. Transcripts for further components of the TGF and IGF systems (e.g. INHA, INHBA, IGF2R and IGFBP2) varied between the first- and final-wave DFs. These results highlight the importance of hormones such as progesterone interacting with local components of both the TGF and IGF systems to affect the maturation of the ovulatory follicle and functional competency of the subsequent CL