Predicted structure of the bovine calcitonin gene-related peptide and the carboxy-terminal flanking peptide of bovine calcitonin precursor

We have isolated from a bovine genomic library a clone which contains the calcitonin (CT) and CT gene-related peptide (CGRP) sequences, using probes representing the human CT and CGRP sequences. Sequence analysis has identified the nucleotide sequence coding for bovine CT, its C-terminal flanking peptide and bovine CGRP. The deduced amino acid sequence of bovine CGRP revealed a significant homology with other CGRPs so far reported. It differs by only one amino acid from rat CGRP alpha and porcine CGRP, and by three and four amino acids from human CGRP beta and alpha respectively. Bovine CT has, however, only 14 out of 32 residues in common with human CT. As in the human CT precursor, the C-terminal flanking peptide of bovine CT precursor is a 21 amino acid peptide. It shares only 11 residues in common with its human counterpart. This study thus provides further evidence that CGRP, in contrast to CT and its C-terminal flanking peptide, is a highly conserved molecule.     

Brain anatomic effects of electroconvulsive therapy. A prospective magnetic resonance imaging study.

To determine prospectively whether electroconvulsive therapy (ECT) produces structural brain changes, 35 inpatients with depression underwent magnetic resonance imaging before and twice after (at 2 to 3 days and at 6 months) completion of a course of brief-pulse, bilateral ECT. The magnetic resonance images were analyzed blindly for evidence of changes in brain structure using two approaches: measurement of regional brain volumes and a pairwise global comparison. Structural brain abnormalities were present in many patients before ECT. The course of ECT produced no acute or delayed (6-month) change in brain structure as measured by alterations of the total volumes of the lateral ventricles, the third ventricle, the frontal lobes, the temporal lobes, or the amygdala-hippocampal complex. In five subjects, the pairwise global comparisons revealed an apparent increase in subcortical hyperintensity, most likely secondary to progression of ongoing cerebrovascular disease during follow-up. Our results confirm and extend previous imaging studies that also found no relationship between ECT and brain damage.     

Effect of repetitive brief episodes of cardiac ischemia on 31P magnetic resonance spectroscopy in the cat

Angina is characterized by brief periods of ischemia followed by reperfusion; the cumulative effect of these episodes on energetics of the myocardium has not been fully elucidated. This study used an in vivo feline model for the assessment of high-energy phosphate compounds during brief sequential periods of ischemia and reperfusion. Nine adult, open-chest, anesthetized cats were prepared with a reversible occluder around the proximal left anterior descending artery and a 1.2-cm-inside diameter coil sutured on the myocardial surface in the distribution of the left anterior descending coronary artery. Levels of PCr, Pi, and ATP (beta-phosphate signal) were measured by 31P MRS in a GE CSI 2-T NMR spectrometer/imager. Measurements were obtained during a control period and during three successive occlusion-deocclusion periods of roughly 12 and 20 min' duration, respectively. The last deocclusion period was observed for 60 min. Electron microscopy was performed in two animals. PCr declined (P less than 0.01) rapidly following each occlusion to 51 +/- 5.2% (occlusion 1), 53 +/- 5.8% (occlusion 2), and 48 +/- 5.7% (occlusion 3) of the control value by 6 min. Pi rose (P less than 0.01) with the three sequential occlusions to 253 +/- 46, 288 +/- 57, and 277 +/- 46%, respectively. PCr and Pi returned to baseline promptly with reperfusion, while ATP showed a gradual decline throughout the experiment, decreasing to 77 +/- 7.2% of control at the end of the last reperfusion (P less than 0.05). Although PCr returned to baseline during reperfusion, ATP did not, suggesting a reduction in the nucleotide pool. These findings indicate that the repeated episodes of ischemia, which are insufficient to produce necrosis, can have an effect on myocardial high-energy phosphate metabolism as evidenced by mild depletion of ATP.     

Indexes of Overall Diet Quality: A Review

This article reviews the published indexes of overall diet quality. Approaches used for measuring overall diet quality include those based on examination of the intake of nutrients, food groups, or a combination of both. A majority of the indexes have been examined in relation to nutrient adequacy only; few have been evaluated for assessment of quality according to current dietary guidelines, namely, a diet relatively low in fat that meets energy and nutrient needs. The indexes of overall diet quality were related to the risk of disease more strongly than individual nutrients or foods. J Am Diet Assoc. 1996; 96:785–791.     

Transmission of HIV-1 in the Breast-Feeding Process

Current laboratory techniques cannot distinguish the mode of vertical transmission (intrauterine, intrapartum, or postnatal) of human immunodeficiency virus type 1 (HIV-1) from mother to infant. The ability to transmit HIV-1 via breastfeeding has been established in 24 case reports, primarily involving mothers who seroconvert after delivery. Whether breast-feeding adds a notable additional risk of HIV-1 infection to the risk from pregnancy is controversial. The importance of the duration and intensity of breast-feeding in modulating the outcome of HIV transmission via breast milk also remains unclear. Factors in breast milk may play important roles in an infant's susceptibility to infection with HIV and in the expression of the virus. Pasteurization and storage enhance the intrinsic, antiviral properties of human milk. Banked human milk is pasteurized to destroy the HIV-1 virus but retains properties that may be helpful to infants of HIV-1-positive mothers in developed countries where breastfeeding is not recommended. For infants in populations where the infant mortality rate is high, the risk of death associated with HIV infection acquired via breast milk is lower than the risk associated with not being breast-fed. J Am Diet Assoc. 1996; 96:267-274.     

Pilot Study to Enhance Start-up of a Multicenter Nutrition Intervention Trial

Multicenter trials are important for answering questions that require large numbers of subjects. Such trials require standardized implementation of behavioral change programs across diverse populations, regions, and staff. Researchers involved with the Trial of Nonpharmacologic Interventions in the Elderly conducted a 17-week pilot study of their most complex intervention (combined weight and sodium reduction) before actual start-up of the main study. This allowed staff to rehearse implementing the program and to identify and address intervention and standardization issues. Registered dietitians in 4 US communities recruited 28 participants for the pilot study, using eligibility criteria similar to those for the main trial. Participant evaluations reflected high satisfaction with the program materials and overall approach. Minor protocol changes suggested by results of the pilot study were made easily in time for start-up of the main study. Reductions in weight and sodium intake were less than targeted but were sufficient to suggest that the intervention would be effective under optimal conditions. This partial achievement of goals in the pilot study underscored the need to allow for a learning curve, for without it standardization and outcomes of the main study would be compromised. J Am Diet Assoc. 1998;98:322–325.     

Guidelines vs practice in the delivery of diabetes nutrition care

The American Dietetic Association and the American Diabetes Association have published recommendations for the nutrition care of people with diabetes. However, the frequency of this care is rarely documented. As part of a study of diabetes care and education practices, the Michigan Diabetes Research and Training Center collected extensive data from 440 randomly selected adults who receive diabetes care from community physicians. These data provided a basis for comparison between diabetes nutrition care as recommended and as delivered in typical American communities. In this population (mean AGE = 61 years; 54% women), 89% (393) had non-insulin-dependent diabetes mellitus (NIDDM). Of these, 152 were managed with insulin (NIDDM/I) and 241 were not managed with insulin (NIDDM/NI). Most of the NIDDM/NI group was overweight (71%) and had elevated levels of glycated hemoglobin (62%) and serum cholesterol (53%). Yet they were significantly less likely than those with NIDDM/I to see a dietitian. The most frequently reported reason for not seeing a dietitian was that a physician had not referred them (53%). More than 90% of those with NIDDM/I or NIDDM/NI who were referred to a dietitian saw one. Because this population was from randomly selected communities, physicians, and patients, the results are probably generalizable to other regions of the United States. This study shows that in community practice, insulin use is the primary marker of the need for nutrition intervention, and the lack of physician referred to a dietitian is an important barrier to people receiving recommended diabetes nutrition care.