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J B Miller

Publications and source records attributed to J B Miller.

At least 55 records · Page 3Linked to original sources
PubMed1996

NMR parameter contrast in abundant-spin images of solids.

Solid state nuclear magnetic resonance imaging (NMRI) techniques have been steadily improving over the years. Today high-resolution images of rigid solids are now accomplished by many different means. For abundant nuclei, the combination of multiple-pulse line narrowing and pulsed field gradients have greatly improved both the resolution and sensitivity of the imaging experiment, but often at the expense of the chemical information in the material. In this paper we discuss means of incorporating NMR parameters in the imaging experiment to generate image contrast which provides information about local variations in the chemistry of the material.

Magnetic Resonance Spectroscopy↗
PubMed1996

Incidence of perioperative myocardial ischemia in TURP patients.

STUDY OBJECTIVE: To determine the incidence of new episodes of myocardial ischemia in patients undergoing transurethral resection of the prostate (TURP). DESIGN: Prospective, nonrandomized study. SETTING: Veterans Administration medical center. PATIENTS: 39 patients undergoing elective TURP. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Myocardial ischemia was detected with a 3-channel ambulatory ECG recorded. The ambulatory ECG recorder was applied preoperatively and removed when the patient left the recovery room. New myocardial ischemia was defined as a 1 mm or greater ST depression or a 2 mm or greater ST elevation from baseline, lasting for 1 minute or longer in at least one lead at the J point plus 60 msec unless this point fell within the T wave, in which case the J point 40 msec or greater was used. ST changes consistent with myocardial ischemia were confirmed by a cardiologist blinded to the patient's clinical course. Seven of 39 TURP patients (18%) had ST segment changes indicative of new myocardial ischemia. These seven patients had more prostate tissue resected and more blood loss than the 32 patients who did not have any myocardial ischemia (p < 0.05). CONCLUSIONS: Patients undergoing TURP have an 18% incidence of myocardial ischemia. Patients undergoing TURP with more prostate tissue resected and greater blood loss are at increased risk for perioperative myocardial ischemia.

Aged↗
PubMed1996

Honey revisited: a reappraisal of honey in pre-industrial diets.

In pre-industrial times, honey was the main source of concentrated sweetness in the diets of many peoples. There are no precise figures for per capita consumption during most periods in history because honey was part of either a hunter-gatherer or subsistence economy. Until now, historians and food writers have proposed that it was a scarce commodity available only to a wealthy few. We do know, however, that in a cash economy honey was sold in large units (gallons and even barrels) and it was present in such abundance that mead, made from honey, was a common alcoholic drink. A reappraisal of the evidence from the Stone Age, Antiquity, the Middle Ages and early Modern times suggests that ordinary people ate much larger quantities of honey than has previously been acknowledged. Intakes at various times during history may well have rivalled our current consumption of refined sugar. There are implications therefore for the role of sugar in modern diets. Refined sugar may not have displaced more nutrient-rich items from our present-day diets but only the nutritionally comparable food, honey.

Diet↗
PubMed1996

Memory for conversation.

Memory for conversation is treated as a source of coherence in social encounters and its connections with social competence are tested in a study of problem-solving conversations. As predicted, accurate recall is found to correlate positively with social competence and negatively with social anxiety. Partners have better memory for their own contributions than for each other's, and this difference is exacerbated by topic importance. Differences in recall are also found for differing amounts of involvement in the conversations. Results are explained in terms of resource allocation during conversation.

Analysis of Variance↗
PubMed1996

Progress, problems, and prospects for gene therapy in muscle.

As the molecular defects that cause many muscle diseases have been identified, research has shifted to finding novel therapies. Gene therapy has been proposed both for correcting primary gene defects of muscle and as a way of using muscle for the production of proteins therapeutic in inflammatory or nonmuscle diseases. Several strategies have been developed to introduce foreign genes into diseased muscles, including myoblast transfer, direct injection of plasmids or DNA-liposome complexes, and infection with modified viruses. Related strategies, using antisense sequences or ribozymes, have been devised to modify gene expression in diseased cells. No method has yet proved itself in the clinic, although current work remains promising and some of the pitfalls that must be overcome have been identified.

Animals↗
PubMed1995

Increased insulin responses to ingested foods are associated with lessened satiety.

In order to assess the relationship between metabolic responses and satiety, four men and five women ate two pairs of foods containing 50 g of available carbohydrate, ordinary and quick-cooking rice and high- and low-amylose puffed rice. Plasma glucose and insulin levels and satiety ratings were assessed over 2 h and food intake measured immediately thereafter. The area under the curve (AUC) of the 2-h glucose response was 1.6 times greater after quick-cooking rice than that for ordinary rice. Similarly, the glucose AUC for the low-amylose rice was 1.5 times higher than that of the high-amylose rice. Insulin responses followed the pattern of the glucose responses. Conversely, the satiety AUC was 1.5 times higher for ordinary rice than for the quick-cooking rice, and 1.5 times higher for high-amylose than for low-amylose rice. Food intake (g) immediately after each 2-h session was significantly related to both the satiety AUC and the last rating score, thereby corroborating the satiety ratings. A significant negative association was found between the individual insulin and satiety AUC responses to the four foods. These results suggest that increased rate of starch digestion and higher insulin responses are associated with lessened satiety.

Adult↗
PubMed1995

The glycaemic index of foods containing sugars: comparison of foods with naturally-occurring v. added sugars.

The primary aim of the present study was to expand the glycaemic index (GI) database by determining the GI and insulin index values of thirty-nine foods containing sugars in healthy adults. The second aim was to examine the hypothesis that glycaemic and insulin responses to foods which contain added sugar(s) are higher than responses to foods containing naturally-occurring sugars. Eight healthy subjects drawn from a pool of eighteen consumed 50 g carbohydrate portions (except 25 g carbohydrate portions for fruits) of the test foods. The GI and insulin index were determined according to standardized methodology and expressed on a scale on which glucose = 100. The median GI and insulin index values of all foods tested were 56 (range 14 to 80) and 56 (range 24 to 124) respectively. The median GI of the foods containing added sugars was similar to that of foods containing naturally-occurring sugars (58 v. 53 respectively, P = 0.08). Likewise, the median insulin index of the foods containing added sugars was not significantly different from that of foods containing naturally-occurring sugars (61 v. 56 respectively, P = 0.16). There was no evidence of 'rebound hypoglycaemia' or excessive insulin secretion relative to the glucose response. We conclude that most foods containing sugars do not have a high GI. In addition, there is often no difference in responses between foods containing added sugars and those containing naturally-occurring sugars.

Adult↗
PubMed1995

Sugars and blood glucose control.

The rise of blood glucose in normal and diabetic subjects after meals varies markedly and depends on many factors, including the source of the carbohydrate, its method of preparation, and the composition of the total meal. Classification of carbohydrates as simple or complex does not predict their effects on blood glucose or insulin. Rapidly absorbed carbohydrates, which produce large blood glucose and insulin responses, may be in the form of both sugars and starches. Sugars added to foods have no different effect on blood glucose from those of sugars alone. The natural sugars in fruit and fruit juices raise blood glucose approximately as much as does sucrose and less than do most refined starchy carbohydrate foods. The optimum amount of sugars in the diet is not known. However, undue avoidance of sugars is not necessary for blood glucose control and is not advised because it may result in increased intakes of fat and high-glycemic-index starch.

Blood Glucose↗
PubMed1995

International tables of glycemic index.

The glycemic index (GI) is a ranking of foods based on their glycemic effect compared with a standard food. It has been used to classify carbohydrate foods for various applications, including diabetes, sports, and appetite research. The purpose of these tables is to bring together all of the published data on the GIs of individual foods for the convenience of users. In total, there are almost 600 separate entries, including values for most common Western foods, many indigenous foods, and pure sugar solutions. The tables show the GI according to both the glucose and white bread (the original reference food) standard, the type and number of subjects tested, and the source of the data. For many foods there were two or more published values, so the mean +/- SEM was calculated and is shown together with the original data. These tables reduce unnecessary repetition in the testing of individual foods and facilitate wider application of the GI approach.

Bread↗
PubMed1995

Intermediate filaments in cardiac myogenesis: nestin in the developing mouse heart.

By using immunohistology combined with immunoblotting, cell culture, and RT-PCR, we show that the intermediate filament protein nestin is transiently expressed in the midembryonic mouse heart. Monoclonal antibody (MAb) Rat-401, known to react with nestin in neural and skeletal muscle cells, was also found to react with ventricular and atrial cells throughout the mouse heart from embryonic day 9 (E9) through E10.5. Both before (E8.5) and after (E11-adult) this brief period, staining with Rat-401 was absent from atrial and ventricular myocytes. To evaluate the specificity of staining with MAb Rat-401 in the heart, we used immunoblotting, cell culture, and RT-PCR to verify that the authentic nestin protein and mRNA were expressed in cardiomyocytes of the E10 mouse. Nestin expression is the first molecular marker for this distinct midembryonic period of heart development.

Animals↗
PubMed1994

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Peer Review↗
PubMed1994

Myogenesis and the intermediate filament protein, nestin.

We show that the intermediate filament protein nestin is expressed in myogenic cells and that multiple mechanisms regulate nestin expression at different stages of myogenesis. Cultured embryonic, fetal, and neonatal mouse limb myoblasts initially expressed nestin in the absence of the four muscle regulatory factors (MRFs) of the MyoD family, whereas nestin and MRFs became coexpressed by myoblasts as culture duration was lengthened. Upon differentiation, nestin was commonly concentrated at the ends, and reduced or absent in the middles, of myotubes formed by mouse limb cells. Nestin was expressed by C2C12 and L6 myoblasts and was distributed throughout C2C12 myotubes, but was entirely absent in myotubes formed by L6 cells, suggesting that nestin is dispensable for fusion and terminal differentiation. Nestin was expressed in C3H10T1/2 cells, but was not expressed in 3T3-L1 cells until transfected with MyoD or myogenin. In mouse somites, nestin was found in both myotomal and dermatomal cells. Thus, nestin is expressed by dermatomal cells and by myoblasts during the earliest stages of myogenesis, and nestin expression can be activated upon MRF transfection. Additional MRF-independent mechanisms must, however, regulate nestin expression, because nestin is found in MRF-negative cells and, conversely, nestin is not uniformly distributed in MRF-expressing myotubes.

3T3 Cells↗
PubMed1994

Characterization and physiological variation in prostaglandin, prostacyclin and thromboxane synthesis by corpora lutea, non-luteal and uterine tissues during pseudopregnancy in the rabbit.

To determine if luteal as well as uterine prostaglandin production is associated with luteal regression, the conversion of (14C) arachidonic acid into prostaglandin (PG) F2 alpha, PGE2, PGD2, prostacyclin (measured as its stable metabolite 6-keto-PGF1 alpha) and thromboxane (measured as its stable metabolite TXB2) was characterized and measured in microsomes from the uterus, corpora lutea and nonluteal tissue of the rabbit on days 8, 12 and 15 of pseudopregnancy. PGF2 alpha production was increased on day 15 compared to days 8 or 12 of pseudopregnancy in corpora lutea and in the uterus. In uterine microsomes, 6-keto-PGF1 alpha production was also elevated on day 15. No significant changes in the production of PGF2 alpha, TXB2 or PGD2 were observed with uterine or luteal microsomes. Arachidonic acid metabolism by microsomes from nonluteal tissue was not significantly different on any day examined. These results suggest that intraluteal, as well as uterine PGF2 alpha production may contribute physiologically to the final phase of luteal regression.

6-Ketoprostaglandin F1 alpha↗
PubMed1994

Somite subdomains, muscle cell origins, and the four muscle regulatory factor proteins.

We show by immunohistology that distinct expression patterns of the four muscle regulatory factor (MRF) proteins identify subdomains of mouse somites. Myf-5 and MyoD are, at specific stages, each expressed in both myotome and dermatome cells. Myf-5 expression is initially restricted to dorsal cells in all somites, as is MyoD expression in neck somites. In trunk somites, however, MyoD is initially expressed in ventral cells. Myogenin and MRF4 are restricted to myotome cells, though the MRF4-expressing cells are initially less widely distributed than the myogenin-expressing cells, which are at all stages found throughout the myotome. All somitic myocytes express one or more MRFs. The transiently distinct expression patterns of the four MRF proteins identify dorsal and ventral subdomains of somites, and suggest that skeletal muscle cells in somites originate at multiple sites and via multiple molecular pathways.

Animals↗
PubMed1994

The oligosaccharide composition of human milk: temporal and individual variations in monosaccharide components.

Oligosaccharides are an important component of human milk, but little is known about variations in their composition. The aim of this study was to determine the temporal and inter-individual variations in carbohydrate composition of human milk during the first 3 months of lactation. Serial milk samples of 10 mothers (eight full-term and two preterm births) were analyzed to determine the concentration of lactose and three monosaccharide components derived from the non-lactose carbohydrate: sialic acid, N-acetylglucosamine, and fucose. In full-term milk, sialic acid and N-acetylglucosamine were found to decrease significantly (p < 0.05) from weeks 1 to 13 postnatally. On average (mean +/- SD), sialic acid decreased by 71% (from 879 +/- 157 to 256 +/- 82 mg/L; p < 0.05) and N-acetylglucosamine by 56% (from 1,459 +/- 282 to 646 +/- 214 mg/L; p < 0.05), while fucose decreased by only 35% (from 660 +/- 192 to 432 +/- 180 mg/L; p > 0.05). On average, lactose concentration increased by 17% over the same period, from 55.4 +/- 4.2 g/L in week 1 to 64.9 +/- 2.3 g/L at 3 months. Preterm milk contained higher concentrations of each component, but temporal changes were similar to those seen in full-term milk. Apart from temporal changes, there were large inter-individual differences in oligosaccharide composition: fucose varied four-fold, sialic acid threefold, and N-acetylglucosamine two-fold among women at the same stage of lactation. The changes observed may simply reflect the aging of the cells responsible for milk secretion, but they are also consistent with a programmed adaptation of the milk composition to the needs of the infant.

Acetylglucosamine↗