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The authors studied gains in student learning when curriculum was changed to include an optional verbal final exam (VF). Students who passed the VF outscored peers on MCAT questions (66.4% [n=160] and 62% [n=285], respectively; p < 0.001), and passing the VF also correlated with higher performance in a range of upper-level science courses., We studied gains in student learning over eight semesters in which an introductory biology course curriculum was changed to include optional verbal final exams (VFs). Students could opt to demonstrate their mastery of course material via structured oral exams with the professor. In a quantitative assessment of cell biology content knowledge, students who passed the VF outscored their peers on the medical assessment test (MAT), an exam built with 40 Medical College Admissions Test (MCAT) questions (66.4% [n = 160] and 62% [n = 285], respectively; p < 0.001);. The higher-achieving students performed better on MCAT questions in all topic categories tested; the greatest gain occurred on the topic of cellular respiration. Because the VF focused on a conceptually parallel topic, photosynthesis, there may have been authentic knowledge transfer. In longitudinal tracking studies, passing the VF also correlated with higher performance in a range of upper-level science courses, with greatest significance in physiology, biochemistry, and organic chemistry. Participation had a wide range but not equal representation in academic standing, gender, and ethnicity. Yet students nearly unanimously (92%) valued the option. Our findings suggest oral exams at the introductory level may allow instructors to assess and aid students striving to achieve higher-level learning.

Successful implementation of cisgenic/intragenic/ingenic technology for crop improvement necessitates a better understanding of the function of native promoters for driving desired gene expression in host plant. Although the genome of grapevine (Vitis vinifera) has been determined, efforts to explore promoter resources for the development of cisgenics are still lacking. Particularly, there is a shortage of constitutive promoters for marker and/or target gene expression in this species. In this work, we utilized an anthocyanin-based color histogram analysis method to evaluate quantitatively a large number of promoters for their ability to activate transgene expression. Promoter fragments corresponding to known genes were amplified from various genotypes and used to drive the VvMybA1 gene of 'Merlot' for anthocyanin production in non-pigmented somatic embryo (SE) explants to infer transcriptional activity. Results revealed that among 15 tested promoters belonging to seven ubiquitin genes, at least three promoters generated constitutive activities reaching up to 100% value of the d35S promoter. In particular, the high activity levels of VvUb6-1 and VvUb7-2 promoters were verified by transient GUS quantitative assay as well as stable anthocyanin expression in sepal and corolla of transgenic tobacco. Variations in promoter activity of different ubiquitin genes in grapevine did not correlate with the presence and sizes of 5' UTR intron, but seemed to be related positively and negatively to the number of positive cis-acting elements and root-specific elements respectively. In addition, several of the 13 promoters derived from a PR1 gene and a PAL gene produced a higher basal activity as compared to previously reported inducible promoters and might be useful for further identification of strong inducible promoters. Our study contributed invaluable information on transcriptional activity of many previously uncharacterized native promoters that could be used for genetic engineering of grapevine.

Fibrates, such as ciprofibrate, fenofibrate, and clofibrate, are peroxisome proliferator-activated receptor-alpha (PPARalpha) agonists that have been in clinical use for many decades for treatment of dyslipidemia. When mice and rats are given PPARalpha agonists, these drugs cause hepatic peroxisome proliferation, hypertrophy, hyperplasia, and eventually hepatocarcinogenesis. Importantly, primates are relatively refractory to these effects; however, the mechanisms for the species differences are not clearly understood. Cynomolgus monkeys were exposed to ciprofibrate at various dose levels for either 4 or 15 days, and the liver transcriptional profiles were examined using Affymetrix human GeneChips. Strong upregulation of many genes relating to fatty acid metabolism and mitochondrial oxidative phosphorylation was observed; this reflects the known pharmacology and activity of the fibrates. In addition, (1) many genes related to ribosome and proteasome biosynthesis were upregulated, (2) a large number of genes downregulated were in the complement and coagulation cascades, (3) a number of key regulatory genes, including members of the JUN, MYC, and NFkappaB families were downregulated, which appears to be in contrast to the rodent, where JUN and MYC are reported to upregulated after PPARalpha agonist treatment, (4) no transcriptional signal for DNA damage or oxidative stress was observed, and (5) transcriptional signals consistent with an anti-proliferative and a pro-apoptotic effect were seen. We also compared the primate data to literature reports of hepatic transcriptional profiling in PPARalpha-treated rodents, which showed that the magnitude of induction in beta-oxidation pathways was substantially greater in the rodent than the primate.

Although they are known to be effective antidiabetic agents, little is published about the toxic effects of carnitine palmitoyltransferase-1 (CPT-1) inhibitors, such as etomoxir (ET). These compounds inhibit mitochondrial fatty acid beta-oxidation by irreversibly binding to CPT-1 and preventing entry of long chain fatty acids into the mitochondrial matrix. Treatment of HepG2 cells with 1 mM etomoxir for 6 h caused significant modulations in the expression of several redox-related and cell cycle mRNAs as measured by microarray analysis. Upregulated mRNAs included heme oxygenase 1 (HO1), 8-oxoguanine DNA glycosylase 1 (OGG1), glutathione reductase (GSR), cyclin-dependent kinase inhibitor 1A (CDKN1 [p21(waf1)]) and Mn+ superoxide dismutase precursor (SOD2); while cytochrome P450 1A1 (CYP1A1) and heat shock 70kD protein 1 (HSPA1A) were downregulated. Real time quantitative PCR (RT-PCR) confirmed the significant changes in 4 of 4 mRNAs assayed (CYP1A1, HO1, GSR, CDKN1), and identified 3 additional mRNA changes; 2 redox-related genes, gamma-glutamate-cysteine ligase modifier subunit (GCLM) and thioredoxin reductase (TXNRD1) and 1 DNA replication gene, topoisomerase IIalpha (TOP2A). Temporal changes in selected mRNA levels were examined by RT-PCR over 11 time points from 15 min to 24 h postdosing. CYP1A1 exhibited a 38-fold decrease by 4 h, which rebounded to a 39-fold increase by 20 h. GCLM and TXNRD1 exhibited 13- and 9-fold increases, respectively at 24 h. Etomoxir-induced oxidative stress and impaired mitochondrial energy metabolism were confirmed by a significant decrease in reduced glutathione (GSH), reduced/oxidized glutathione ratio (GSH/GSSG), mitochondrial membrane potential (MMP), and ATP levels, and by concurrent increase in oxidized glutathione (GSSG) and superoxide generation. This is the first report of oxidative stress caused by etomoxir.

Plant regeneration from grapevine (Vitis spp.) via somatic embryogenesis typically is poor. Recovery of plants from Vitis rotundifolia Michx. (muscadine grape) is particularly problematic due to extremely low efficiency, including extended culture durations required for embryo-plant conversion. Poor plant recovery is an obstacle to the selection of improved genetically modified lines. Somatic embryos (SEs) of V. rotundifolia cultivar Delicious (Del-HS) and Vitis vinifera L cultivar Thompson Seedless (TS) were used to identify culture media and conditions that promoted embryo differentiation and plant conversion; this resulted in a two-step culture system. In comparative culture experiments, C2D medium containing 6% sucrose was the most effective, among four distinct formulae tested, for inducing precocious SE germination and cell differentiation. This medium, further supplemented with 4 µM 6-benzylaminopurine (C2D4B), was subsequently determined to enhance post-germinative growth of SE. MS medium supplemented with 0.5 µM 1-naphthaleneacetic acid (MSN) was then utilized to stimulate root and shoot growth of germinated SE. An average of 35% and 80% 'Del-HS' and 'TS' SE, respectively, developed into plants. All plants developed robust root and shoot systems and exhibited excellent survival following transfer to soil. Over 150 plants of 'Del-HS' were regenerated and established within 2.5 months, which is a dramatic reduction from the 6- to 12-month time period previously required. Similarly, 88 'TS' plant lines were obtained within the same time period. Subsequently, seven out of eight Vitis cultivars exhibited significantly increased plant conversion percentages, demonstrating broad application of the two-step culture system to produce the large numbers of independent plant lines needed for selection of desired traits.

This study examined the historical performance of students at Michigan State University in 12 life sciences courses over 13 yr to find variables impacting student success. Hierarchical linear modeling predicted 25.0–62.8% of the variance in students’ grades in the courses analyzed. The primary predictor of a student's course grade was his or her entering grade point average; except for the second course in a series (i.e., Biochemistry II), in which the grade for the first course in the series (i.e., Biochemistry I) was often the best predictor, as judged by β values. Student gender and major were also statistically significant for a majority of the courses studied. Female students averaged grades 0.067–0.303 lower than their equivalent male counterparts, and majors averaged grades were 0.088–0.397 higher than nonmajors. Grades earned in prerequisite courses provided minimal predictive ability. Ethnicity and involvements in honors college or science residential college were generally insignificant.

Peroxisome proliferation in the liver is a well-documented response that occurs in some species upon treatment with hypolipidemic drugs, such as fibrates. Typically, liver peroxisome proliferation has been estimated by direct counting via electron microscopy, as well as by gene expression, enzyme activity, and immunolabeling. We have developed a novel method for the immunofluorescent labeling of peroxisomes, using an antibody to the 70-kDa peroxisomal membrane protein (PMP70) coupled with fluorescent nanocrystals, Quantum Dots. This method is applicable to standard formalin-fixed, paraffin-embedded tissues. Using this technique, a dose-dependent increase in PMP70 labeling was evident in formalin-fixed liver sections from fenofibrate-treated rats. In formalin-fixed liver sections from cynomolgus monkeys given ciprofibrate, quantitative image analysis showed a statistically significant increase in PMP70 labeling compared to control; the increase in hepatic PMP70 protein levels was corroborated by immunoblotting using total liver protein. An increase in hepatic peroxisome number in ciprofibrate-treated monkeys was confirmed by electron microscopy. An advantage of the Quantum Dot/PMP70 method is that a single common protocol can be used to label peroxisomes from several different species, and many of the common problems that arise with immunolabeling, such as fading and low signal strength, are eliminated.

Two hundred and fifty-eight patients with small cell carcinoma and 185 patients with adenocarcinoma were centrally randomized to receive either cyclophosphamide (1000 mg/m2 every 3 weeks) iv or cyclophosphamide (700 mg/m2 every 3 weeks) iv plus CCNU (70 mg/m2 every 6 weeks) orally. Those patients who were initially treated with the single agent were then treated with CCNU (130 mg/m2 every 6 weeks) at the time of cyclophosphamide failure. Objective tumor regression occurred more frequently with the combination regimen in patients with small cell carcinoma (43% vs 22%, P = 0.002), but no difference in response rates was apparent in patients with adenocarcinoma. In both cell types patients survived somewhat longer following treatment with the combination. The overall incidence of severe toxicity was equal for the two regimens in both cell types; however, the therapeutic index of the combination was superior to that of the single agent in small cell carcinoma. Severe drug toxicity was more frequent in small cell carcinoma patients with extensive disease, and survival was reduced in both cell types with extensive disease. Survival was better for ambulatory patients in both cell types and women survived longer than men. In women with small cell carcinoma, ambulatory status also was associated with a higher incidence of tumor regression. In patients with small cell carcinoma those who had prior lung surgery survived longer than those without prior surgery. Previous radiation therapy was associated with a reduced incidence of objective regression in men with small cell carcinoma. In both cell types patients with tumor regression lived longer than nonresponders; however, objective disease stability was associated with improved survival only in patients with adenocarcinoma. Stratification in future studies should consider extent of disease, performance status, sex, and prior therapy.

This report describes the preliminary results from a randomized study comparing megestrol acetate with tamoxifen in the treatment of postmenopausal women with advanced breast cancer, correlating estrogen receptors (ER) and progesterone receptor (PgR) status with response. Patients received megestrol acetate (40 mg) orally four times daily or tamoxifen (10 mg) orally twice daily. If the initial therapy failed, patients were crossed over to the alternate treatment. Of 197 patients entered in the study, 190 were considered evaluable. The overall response rates were 35% with megestrol acetate and 42% with tamoxifen. Twenty-three percent (7/30) of patients responded to megestrol acetate after being crossed over from tamoxifen, while 22% (6/27) responded to tamoxifen after being crossed over from megestrol acetate. Response did not correlate significantly with combined receptor (ie, ER plus PgR) levels. A significant trend was seen between ER level and response only in the tamoxifen group. There was no association between PgR levels and response for either tamoxifen or megestrol acetate.

Bone marrow chromosome studies were done on three patients who developed acute nonlymphocytic leukemia 5 to 19 months after completion of adjuvant chemotherapy for breast cancer, and on 17 breast cancer patients without hematologic disease 2 to 30 months after similar adjuvant therapy. Clones of cells with multiple cytogenetic abnormalities were demonstrated in two of the three leukemic patients. No chromosomally abnormal clones or evidence of increased chromosome damage was found in the 17 nonleukemic individuals. Although leukemias induced by chemotherapy, and particularly by alkylating agents, typically show multiple cytogenetic alterations, it appears that patients recently exposed to these agents, but without obvious hematopoietic disorders, do not have a high frequency of aberrant marrow clones. Additional approaches may be needed for early identification of patients at increased risk for chemotherapy-induced leukemia.

Two hundred seventy-five patients with breast cancer and no axillary metastases had mastectomies and axillary node dissection performed during the period between 1970 and 1979 at The Fox Chase Cancer Center. They had a mean age of 60 years (range, 21-91) and 38 (14%) patients have had recurrence to date. Poor histologic differentiation and skin involvement were related to a high risk of recurrence. Those patients with skin infiltration by tumor or a poorly differentiated tumor had a 53 +/- 9% expected five-year tumor-free survival, whereas patients without these had a 90 +/- 2% expected five-year tumor-free survival. Tumor involvement of the lymphatic vessels within the breast and estrogen receptor protein positivity or negativity were not helpful for identifying a subpopulation at increased risk of recurrence. Large tumor size was not a poor prognostic indicator for a patient subpopulation. These factors should be considered as indicators for inclusion in clinical trials and adjuvant therapy and used as stratification points for the analysis of the data developed in these trials.

Hormonal therapy is very effective in the treatment of patients with metastatic breast cancer. Response to various therapies leads to improved quality of life and prolonged survival. This clinical trial compared two commonly utilized additive hormonal agents, tamoxifen citrate and megestrol acetate (Megace). Preliminary data indicate equal efficacy and equal toxicity of these two hormones and suggests that both are suitable for first-line hormonal treatment of stage IV breast cancer.

One hundred and forty-four patients with advanced renal cell cancer were evaluated for objective response to single-agent treatment with megestrol acetate, VP-16-213, cyclophosphamide, or dianhydrogalactitol. In view of the low order of response observed, these agents do not appear to be effective in the treatment of metastatic renal cell cancer. Performance status and a relatively long interval from onset of primary symptoms to study entry were the most favorable prognostic variables affecting time to progression and survival for patients in this study.