Pleomorphic adenoma of the nasal cavity: a case report.

Pleomorphic adenomas of the nasal cavity are rare. We describe the case of a middle-aged white man who presented to our clinic with a long history of unilateral nasal obstruction. Preoperative imaging was performed, and the patient was taken to the operating room for endoscopic excision of the lesion.

Assays for determination of protein concentration.

Biochemical analysis of proteins relies on accurate quantitation of protein concentration. This unit describes how to perform commonly used protein assays, e.g.

P39, a novel soybean protein allergen, belongs to a plant-specific protein family and is present in protein storage vacuoles.

Soybean lecithins are seeing increasing use in industry as an emulsifier and food additive. They are also a growing source of human food allergies, which arise principally from the proteins fractionating with the lecithin fraction during manufacture. A previous study (Gu, X.

Use of a laboratory exercise on molar absorptivity to help students understand the authority of the primary literature.

To promote understanding of the authority of the primary literature in students taking our biochemistry laboratory courses, a biochemistry laboratory exercise on the determination of an acceptable molar absorptivity value of 2-nitrophenol (2-NP) was developed. This made the laboratory course much more relevant by linking to a thematic thread, β-galactosidase, that scaffolds concepts in one exercise with those in later exercises. The substrate for the continuous assay of β-galactosidase is the chromogenic 2-nitrophenyl-β-D-galactopyranoside that produces 2-NP.

Assays for determination of protein concentration.

Biochemical analysis of proteins relies on accurate quantitation of protein concentration. This appendix describes how to perform commonly used protein assays, e.g.

Cognitive development and the complexities of the undergraduate learner in the science classroom*.

Students' reactions to classroom learning and the mastery of science vary along a wide spectrum of attitudes and emotions. In particular, we argue here that how learners encounter and learn subject matter is a function of their level of cognitive development. We describe the stages of cognitive development based on the work of William Perry and demonstrate their relevance to the undergraduate science classroom.

A mechanistic foundation for instructor-regulated collective learning.

The theory of memory and the ability to influence learning with conscious and unconscious factors, both internal and external, is reviewed. From a connectionist view of memory, the interactive compensatory model of learning is introduced, with an emphasis on the plastic components (motivation, prior knowledge, and metacognition) that can be regulated. Expert students, but not naive students, have a considerable ability to self-regulate their learning processes and improve performance in undergraduate courses.

The human side of science education: Using McGregor's theory Y as a framework for improving student motivation*.

Student motivation is correlated with learning. Douglas McGregor's Theory X and Theory Y as a basis for understanding and improving motivation in the business world can be directly applied to the science classroom. Teachers with a Theory Y perspective (students naturally want to learn) provide increased motivation for students and promote more active learning than Theory X-style teachers who do not view students as active learners.

C-Terminal 23 kDa polypeptide of soybean Gly m Bd 28 K is a potential allergen.

Gly m Bd 28 K is a major soybean (Glycine max Merr.) glycoprotein allergen. It was originally identified as a 28 kDa polypeptide in soybean seed flour.

Stability of the allergenic soybean Kunitz trypsin inhibitor.

The soybean Kunitz trypsin inhibitor (SKTI) is a 21.5 kDa allergenic protein that belongs to the family of all antiparallel beta-sheet proteins that are highly resistant to thermal and chemical denaturation. Spectroscopic and biochemical techniques such as circular dichroism (CD), ANS fluorescence and proteolysis were used to study its molecular structure under denaturing conditions such as acid and heat to which these allergens are commonly exposed during food processing.

Comparison of chlorophyll and carotenoid concentrations among Russian wheat aphid (Homoptera: Aphididae)-infested wheat isolines.

Russian wheat aphid, Diuraphis noxia (Mordvilko), feeding injury on 'Betta' wheat isolines with the Dn1 and Dn2 genes was compared by assessing chlorophyll and carotenoid concentrations, and aphid fecundity. The resistant Betta isolines (i.e.

Facilitating student understanding of buffering by an integration of mathematics and chemical concepts.

We describe a simple undergraduate exercise involving the titration of a weak acid by a strong base using a pH meter and a micropipette. Students then use their data and carry out graphical analyses with a spreadsheet. The analyses involve using mathematical concepts such as first-derivative and semi-log plots and provide an opportunity for collaboration between biochemistry and mathematics instructors.

Kinetic behavior of the Arabidopsis thaliana leaf formate dehydrogenase is thermally sensitive.

Two previous kinetic studies on the Arabidopsis thaliana leaf NAD-dependent formate dehydrogenase (EC 1.2.1.

Reversible denaturation of the soybean Kunitz trypsin inhibitor.

The soybean Kunitz trypsin inhibitor (SKTI) is a beta-sheet protein with unusual stability to chemical and thermal denaturation. Different spectroscopic criteria were used to follow the thermal denaturation and renaturation of SKTI. Upon heating to 70 degrees C, changes in UV difference spectra showed increased absorbance at 292 and 297 nm, attributable to perturbation of aromatic residues.

Identification and analysis of a conserved immunoglobulin E-binding epitope in soybean G1a and G2a and peanut Ara h 3 glycinins.

To identify conserved immunoglobulin E (IgE)-binding epitopes among legume glycinins, we utilized recombinant soybean G2a and G2a-derived polypeptide fragments. All of these fusion polypeptides bound IgE, and the C-terminal 94-residue fragment appeared to bind more IgE. Using synthetic peptides we identified S219-N233 (S(219)GFAPEFLKEAFGVN(233)) as the dominant IgE-binding epitope.

Identification of IgE-binding proteins in soy lecithin.

Background: Soy lecithin is widely used as an emulsifier in processed foods, pharmaceuticals and cosmetics. Soy lecithin is composed principally of phospholipids; however, it has also been shown to contain IgE-binding proteins, albeit at a low level. A few clinical cases involving allergic reactions to soy lecithin have been reported.

Oxidative responses of resistant and susceptible cereal leaves to symptomatic and nonsymptomatic cereal aphid (Hemiptera: Aphididae) feeding.

The impact of the leaf-chlorosis-eliciting Russian wheat aphid, Diuraphis noxia (Mordvilko), and the nonchlorosis-eliciting bird cherry-oat aphid, Rhopalosiphum padi (L.), feeding on D. noxia-susceptible and -resistant cereals was examined during the period (i.

Soybean glycinin G1 acidic chain shares IgE epitopes with peanut allergen Ara h 3.

Background: The identification of IgE epitopes for proteins is the first step in understanding the interaction of allergens with the immune system. Proteins from the legume family have shown in vitro cross-reactivity in IgE-binding assays, but this cross-reactivity is rarely clinically significant. Resolution of this discrepancy requires IgE epitope mapping of legume family protein allergens.

Formate dehydrogenase in Arabidopsis thaliana: characterization and possible targeting to the chloroplast.

Formate dehydrogenase (E.C. 1.

Purification of a protein phosphatase from chloroplast stroma capable of dephosphorylating the light-harvesting complex-II.

A protein phosphatase was purified from the stroma of Pea (Pisum sativum L.) chloroplasts that is capable of dephosphorylating synthetic phosphopeptides. Following chromatographic purification of greater than 400-fold, two-dimensional electrophoresis indicated that the stromal protein phosphatase is a 29-kD protein.