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Soybean agglutinin (SBA) protein, also known as soybean lectin, is regarded as an anti‐nutrient due to its negative effect on the ability of monogastric animals to gain weight following consumption of raw soybean seed. Historically, SBA has been measured using a time‐consuming and cumbersome hemagglutination procedure. The objective of our research was to obtain a validated methodology that is precise and accurate in the measurement of SBA while allowing minimally equipped laboratories to effectively conduct the analysis, thus our focus was on evaluating an existing commercially available ELISA, an enzyme‐linked‐lectin‐assay (ELLA), and a hybrid ELISA/ELLA. A new ELLA technique that can detect and quantify lectins was chosen and modified specifically for the quantitation of SBA in soybean seed. The proposed ELLA methodology is similar to a standard sandwich ELISA, and uses polyacrylamide‐linked N‐acetylgalactosamine (Gal–NAc–PAA) for a capture phase and the biotinylated version (Gal–NAc–PAA–Biotin) for detection. Based upon the validation data, the ELLA method can precisely and accurately determine soybean lectin levels in soybean seed. The validated ELLA method was used to quantify SBA in nine commercial soybean varieties introduced between 1972 and 2008 and demonstrated that the natural variability of SBA is subject to the effects of genotype and environment.  相似文献   
2.
Islet-brain 1 (IB1), a regulator of the pancreatic beta-cell function in the rat, is homologous to JIP-1, a murine inhibitor of c-Jun amino-terminal kinase (JNK). Whether IB1 and JIP-1 are present in humans was not known. We report the sequence of the 2133-bp human IB1 cDNA, the expression, structure, and fine-mapping of the human IB1 gene, and the characterization of an IB1 pseudogene. Human IB1 is 94% identical to rat IB1. The tissue-specific expression of IB1 in human is similar to that observed in rodent. The IB1 gene contains 12 exons and maps to chromosome 11 (11p11.2-p12), a region that is deleted in DEFECT-11 syndrome. Apart from an IB1 pseudogene on chromosome 17 (17q21), no additional IB1-related gene was found in the human genome. Our data indicate that the sequence and expression pattern of IB1 are highly conserved between rodent and human and provide the necessary tools to investigate whether IB1 is involved in human diseases.  相似文献   
3.
Ras associated with diabetes (Rad), a new ras-related GTPase, was recently identified by subtractive cloning as an mRNA in skeletal muscle that is overexpressed in NIDDM. To better understand its metabolic significance, we measured skeletal muscle Rad expression in well-characterized insulin sensitive (IS) and insulin resistant (IR) subjects with normal glucose tolerance and in untreated NIDDM patients. We found no differences in expression of Rad mRNA levels among IS, IR, and NIDDM groups using a ribonuclease protection assay (0.22 +/- 0.06, 0.13 +/- 0.01, and 0.16 +/- 0.02 relative units, respectively; NS) and no differences in Rad protein expression using a specific anti-peptide Rad antibody (1.05 +/- 0.18, 1.14 +/- 0.08, and 1.08 +/- 0.21 units/mg protein, respectively; NS). However, Rad protein levels were positively correlated with BMI (r = 0.43, P = 0.03) and percentage body fat (r = 0.55, P < 0.005), two independent measures of obesity, and negatively correlated with resting metabolic rate (r = 0.49, P = 0.01). In multiple regression analyses, percentage body fat and resting metabolic rate independently accounted for 30 and 10% of individual variability in muscle Rad protein expression. In conclusion, Rad expression in skeletal muscle is not altered as a function of insulin resistance or NIDDM in humans. However, these data, for the first time, implicate a role for Rad in regulating body composition and energy expenditure and provide a framework for studies designed to elucidate Rad's cellular functions.  相似文献   
4.
The conserved residue Asp477 in yeast transketolase is located in the substrate channel of the enzyme and forms a hydrogen bond with the C2-hydroxyl group of the acceptor substrate. The significance of this interaction for the recognition of the preferred acceptor substrates, D-alpha-hydroxyaldehydes was investigated by site-directed mutagenesis. In the wild-type enzyme the kcat/KM values are by three to four orders of magnitude lower for 2-deoxyaldoses or substrates with L-configuration at the C2-atom. In the Asp477 Ala mutant, the kcat/KM values for D-alpha-hydroxyaldehydes are decreased by a thousandfold, while the kcat/KM values for substrates with L-configuration or 2-deoxyaldoses are similar to wild-type enzyme. These results indicate that Asp477 is involved in determining the enantioselectivity of transketolase.  相似文献   
5.
One hundred eleven (58%) of 191 adolescent inpatients previously admitted to the emergency wards at the Child and Adolescent Psychiatric Clinics in the cities of Uppsala and G?teborg participated in a 2-4 year follow-up evaluation. The prevalence, incidence, and stability of depressive symptoms, suicidal ideation, and suicide attempts among the adolescents, and predictors of follow-up functioning were examined. Although a majority of the patients substantially reduced their depressive symptoms over the 2-4 year period, a smaller group (13%), mainly girls (94%), continued reporting high symptom levels at follow-up, and one out of five adolescents had moderate-severe levels of suicidal ideation. The accumulated frequency of suicide attempts among the patients shortly prior to hospitalization and during the follow-up was 59% including two patients who committed suicide. Significant predictors of depressive symptom severity at follow-up were depressive symptom scores and V-diagnoses at inpatient assessment. Previous suicide attempts before hospitalization, high levels of self-reported depressive symptoms and nonintact family status at inpatient assessment predicted suicide attempts during the follow-up period. The high prevalence of attempted and completed suicide in this clinical group underscores the importance of developing effective treatments for suicidal adolescents.  相似文献   
6.
Conceptual tools for planning for the wireless classroom   总被引:2,自引:0,他引:2  
Abstract  Wireless and mobile devices are beginning to offer stunning new technical capabilities for collaborative learning. Yet, researchers in this field must recognise the importance of complementing these technical advances with improved understanding of the patterns of classroom activity that most need support. The approach taken in the work reported in this paper has been to create conceptual tools that help thinking and talking about technology-supported collaborative learning. A particularly powerful tool is Collaborative Design Patterns, which captures common learning situations and benefits in written form. This paper uses four classroom scenarios to describe eight patterns. These patterns fall into two categories: whole-activity patterns, which suggest ways to organise one or more class periods, and smaller-grained support patterns.  相似文献   
7.
Abstract An important challenge faced by many teachers as they involve students in science investigations is measuring (‘assessing’) students' progress. Our detailed requirements analysis in a particular school district led to the idea that what teachers need most are ways to increase the quality of the information they have about what students know and can do, not automation of typical assessment practices. We see handheld computers as promising tools for addressing this need because they can give students and teachers frequent, integral access to new ways of expressing and communicating what they know and can do. Our requirements analysis has led us to emphasize a need for handheld-based tools that ‘informate’ science instruction by:
  • • Being oriented to the needs of teachers in transition to inquiry-oriented pedagogy;
  • • expanding the range of assessment tasks through a new representational medium and communication infrastructure;
  • • creating new roles for students in expressing what they know and can do; and
  • • focusing both students' and teachers' attention on scientific concepts.
  相似文献   
8.
BACKGROUND: Despite the early excitement regarding the possible uses of computers in medical care in the 1980s, the computer has not had much effect on routine outpatient medicine except for billing and accounting. METHODS: An emerging comprehensive ambulatory care computer system, The Medical Record (TMR), is used extensively in a large family practice, the Duke Family Medicine Center. TMR is the central system for accounting, appointments, billing, and reporting of laboratory results, radiographic findings, and medications. TMR also records problem lists and generates prompts to the clinicians for needed health maintenance, laboratory tests, and reminder letters. The most innovative function of TMR is the computerized obstetric patient record, which can be accessed from multiple sites. Cost savings compared with a manual system were found to be in excess of $7 per patient visit or approximately $500,000 per year for the Duke Family Medicine Center. RESULTS AND CONCLUSIONS: A comprehensive computer system in a large family practice is cost effective and facilitates better patient care through improved access to patient data.  相似文献   
9.
We demonstrate a single-polarization cladding-pumped Er : Yb optical amplifier using a dual-pass design with a Faraday rotator mirror and nonpolarization-maintaining gain fiber. Over a 25-nm range centered at 1562 nm, the amplifier output exceeds 1 W and maintains a polarization extinction ratio greater than 22 dB. We investigate enhanced relative intensity noise inherent in the dual-pass configuration and discuss scaling to higher powers.  相似文献   
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