The Drosophila segmentation gene runt has an extended cis-regulatory region that is required for vital expression at other stages of development.

The Drosophila runt gene functions in several developmental pathways during embryogenesis. This gene was initially characterized due to the pivotal role that it plays in the genetic regulatory network that establishes the segmented body pattern. Recently it was found that this X-chromosome-linked gene is one of several dosage-sensitive, X-linked components that is involved in activating the Sex-lethal gene in blastoderm stage female embryos. Finally, this gene is also extensively re-expressed in later stages of embryogenesis in the developing nervous system where it plays an important role in the development of specific neural lineages. We have initiated an analysis of the runt cis-regulatory region in order to investigate runt's roles in these (and other) developmental pathways. Analysis of both the function and the expression patterns of runt genes with truncated cis-regulatory regions indicates that there are multiple elements that make quantitative contributions to runt regulation during segmentation. We find that sequences that are more than 8.5 kb upstream of the runt promoter are necessary for normal expression during the post-blastoderm stages of embryogenesis. Genetic experiments indicate that the post-blastoderm expression of runt is vital to the organism.

Effects of a behavioral weight loss program stressing calorie restriction versus calorie plus fat restriction in obese individuals with NIDDM or a family history of diabetes.

OBJECTIVE: The aim of this randomized trial was to compare the effects of a behavioral intervention focusing on either calorie restriction alone or calorie plus fat restriction on weight loss and changes in lipids and glycemic control in individuals with non-insulin-dependent diabetes mellitus (NIDDM) or a family history of diabetes. RESEARCH DESIGN AND METHODS: We recruited 44 obese women with NIDDM and 46 obese women with a family history of NIDDM and randomly assigned these subjects to calorie restriction (CAL) or to calorie plus fat restriction (CAL + FAT). All subjects participated in a 16-week behavioral weight loss program, with training in diet, exercise, and behavior modification. Subjects assigned to the CAL condition were given a 1,000-1,500 kcal/day goal and self-monitored calories consumed. Subjects assigned to the CAL+FAT condition had the same calorie goal, but were also given a fat goal (grams of fat/day), to produce a diet with < 20% of calories from fat; this group monitored both calories and fat grams. RESULTS: Among NIDDM subjects, weight loss of the subjects in the CAL+FAT condition was significantly greater than subjects in the CAL condition (7.7 vs. 4.6 kg) and the CAL+FAT condition group also maintained their weight loss better at the 1-year follow-up (5.2 vs. 1.0 kg). Significant decreases in glucose, high-density lipoprotein (HDL) cholesterol, and total cholesterol were seen after 16 weeks of treatment among NIDDM subjects; these changes were similar in CAL and CAL+FAT groups, but a greater proportion of subjects in CAL condition required oral hypoglycemic medication. At the 1-year follow-up, all parameters had returned to baseline. No significant differences in weight loss or physiological changes were seen between CAL and CAL+FAT conditions in subjects with a family history of diabetes. CONCLUSIONS: These results suggest that using the combination of calorie and fat restriction may help promote weight loss in obese NIDDM patients. No other long-term benefits of this regimen were observed.

Weight cycling, psychological health, and binge eating in obese women.

This study examined the relationship between weight cycling and psychological health in 120 obese women. Weight cycling was defined in 2 ways by retrospective self-report: total lifetime weight loss and total number of weight cycles > or = 20 lbs (> or = 9.07 kg). Psychological self-report measures assessed psychiatric symptoms, eating behavior, mood, stress, and perceptions of physical health. Of the 52 associations between weight cycling and psychological parameters, 8 were significant, with the most consistent association being between weight cycling and binge eating. Binge eating was also strongly associated with psychological distress, as found in previous studies. After adjusting for binge eating, however, weight cycling was independently related to only one of the psychological measures: perceived physical health.

Nutritional management of catabolic acute renal failure requiring renal replacement therapy.

Catabolic acute renal failure patients have a high incidence of morbidity and mortality despite advances in dialytic and lifesaving technologies. Malnutrition is a complicating factor in the treatment of these patients. Early and aggressive nutritional support may positively impact eventual outcome. Continuous renal replacement therapy (CRRT) enables delivery of this support. This article reviews nutritional support in acute renal failure for individuals undergoing these therapies.

Isolation of the Drosophila segmentation gene runt and analysis of its expression during embryogenesis.

runt is one of the genes required for establishment of the segmented body pattern of the Drosophila embryo. We have isolated DNA sequences containing this gene using P-element transposon tagging. Southern blot analyses of six different DNA rearrangements that are associated with runt mutations revealed a minimal region of 8.5-kb of DNA that was important for function. In germ line transformation experiments, a 14.5-kb segment of DNA that spanned this minimal region provided significant, although not full, levels of runt activity. The runt gene encoded a 2.6-kb poly(A)+ RNA that underwent a series of dynamic changes in its spatial and temporal patterns of accumulation during embryogenesis. The runt RNA was most abundant at the blastoderm stage when it showed the seven stripes of expression characteristic of other Drosophila pair-rule genes.

Overlapping genes of Drosophila melanogaster: organization of the z600-gonadal-Eip28/29 gene cluster.

The Drosophila gonadal (gdl) gene is a member of a gene cluster that maps cytogenetically to the 71CD interval of chromosome 3. The gene is bordered distally by z600, a gene expressed predominantly during early embryogenesis, and proximally by Eip28/29, a gene regulated by ecdysone in Drosophila cell lines. gdl can be expressed in either of two modes in adults: gdlF expression leads to the transcripts 1300 and 1000, which are found in the ovaries, whereas gdlM expression leads to the transcripts 1500 and 1200, which are found in the testes. In situ hybridization analysis reveals that this expression occurs in the germ line during oogenesis and spermatogenesis. Structural studies identify an unusual gdl sequence organization. The ovarian and testes transcripts differ at their 5' ends because of the utilization of different transcription initiation sites. This result indicates that alternative promoter usage is responsible for sex-specific gdl expression. Within an expression mode, the two transcripts differ at their 3' ends as a result of multiple polyadenylation site usage; one of these sites resides within the 5' exon of the Eip28/29 gene. gdl is overlapped by z600 as well because the z600 transcript is polyadenylated at position +91 of the gdlM transcripts. An analysis of germ-line transformants reveals that gdl can be expressed properly outside the overlapping gene environment because a 1.8-kb DNA region contains all the sequences necessary for gdl sex-specific expression.

Effect of the number of high-fat and low-fat cues on food choice.

This study examined the effects on food choice of increasing the number of healthy items available (fruit) and decreasing the number of unhealthy items available (candy bars). A similar choice, involving nonfood items, was also examined. Two hundred eighty-nine men and women were randomly assigned to 1 of 4 experimental groups: (a) control group, (b) increased number of fruits, (c) decreased number of candy bars, and (d) combination. Between 30% and 40% of participants chose fruit regardless of the amount of fruit and candy presented: there was no effect of increasing fruit or decreasing candy bars. However, restrained participants and current dieters were more likely to choose fruit. In contrast, both stimulus control techniques were effective in increasing the percentage of participants choosing a nonfood item. These results suggest that stimulus control may not be sufficient to modify food choice: other powerful factors affect eating behavior, and these must be considered.

Prescribing exercise in multiple short bouts versus one continuous bout: effects on adherence, cardiorespiratory fitness, and weight loss in overweight women.

OBJECTIVE: To investigate whether prescribing exercise in several short-bouts versus one long-bout per day would enhance exercise adherence, cardiorespiratory fitness, and weight loss in overweight adult females in a behavioral weight control program. DESIGN: Randomized controlled trial with subjects randomized to either a short-bout exercise group (SB, n = 28, age = 40.4 +/- 5.9 yrs) or a long-bout exercise group (LB, n = 28, age = 40.9 +/- 7.3 yrs), with subjects followed for a period of 20 weeks. Both groups were instructed to exercise 5 days per week with exercise duration progressing from 20 to 40 min per day. The LB group performed one exercise bout per day, whereas the SB group performed multiple 10 min bouts of exercise per day. The recommended caloric intake for all subjects was 5022-6277 kJ/day (1200-1500 kcal/day), with fat reduced to 20% of caloric intake. SUBJECTS: Fifty-six obese, sedentary females (BMI = 33.9 +/- 4.1 kg/m2). MEASUREMENTS: Exercise participation was assessed from self-reported diaries and Tri-Trac Accelerometers. Cardiorespiratory fitness was assessed using a submaximal cycle ergometer test. RESULTS: Exercising in multiple short-bouts per day improved adherence to exercise: the SB group reported exercising on a greater number of days (mean +/- s.d. = 87.3 +/- 29.5 days vs 69.1 +/- 28.9 days; P < 0.05) and for a greater total duration (223.8 +/- 69.5 min/week vs 188.2 +/- 58.4 min/week; P = 0.08) than the LB group. Predicted VO2Peak increased by 5.6% and 5.0% for the LB and SB groups, respectively (P < 0.05). There was a trend for the weight loss to be greater in the SB group (-8.9 +/- 5.3 kg) compared to the LB group (-6.4 +/- 4.5 kg; P < 0.07). CONCLUSION: These results suggest that short-bouts of exercise may enhance exercise adherence. Short-bouts of exercise may also enhance weight loss and produce similar changes in cardiorespiratory fitness when compared to long-bouts of exercise. Thus, short-bouts of exercise may be preferred when prescribing exercise to obese adults.