Brain Response to Food Stimulation in Obese,Normal Weight,and Successful Weight Loss Maintainers

As many people struggle with maintenance of weight loss, the study of successful weight loss maintainers (SWLM) can yield important insights into factors contributing to weight loss maintenance. However, little research has examined how SWLM differ from people who are obese or normal weight (NW) in brain response to orosensory stimulation. The goal of this study was to determine if SWLM exhibit different brain responses to orosensory stimulation. Brain response to 1‐min orosensory stimulation with a lemon lollipop was assessed using functional magnetic resonance imaging among 49 participants, including SWLM (n = 17), NW (n = 18), and obese (n = 14) controls. Significant brain responses were observed in nine brain regions, including the bilateral insula, left inferior frontal gyrus, left putamen, and other sensory regions. All regions also exhibited significant attenuation of this response over 1 min. The SWLM exhibited greater response compared with the other groups in all brain regions. Findings suggest that the response to orosensory stimulation peaks within 40 s and attenuates significantly between 40 and 60 s in regions associated with sensation, reward, and inhibitory control. Greater reactivity among the SWLM suggests that greater sensory reactivity to orosensory stimulation, increased anticipated reward, and subsequently greater inhibitory processing are associated with weight loss maintenance.     

Amount of Food Group Variety Consumed in the Diet and Long‐Term Weight Loss Maintenance

Objective: Decreases in variety of foods consumed within high‐fat‐dense food groups and increases in variety of foods consumed within low‐fat‐dense food groups are associated with lower energy intake and greater weight loss during obesity treatment and may assist with weight loss maintenance. This study examined food group variety in 2237 weight loss maintainers in the National Weight Control Registry, who had lost 32.2 ± 18.0 kg (70.9 ± 39.5 lbs) and maintained a weight loss of at least 13.6 kg (30 lbs) for 6.1 ± 7.7 years. Research Methods and Procedures: At entry into the registry, registry members completed a food frequency questionnaire from which amount of variety consumed from different food groups was assessed. To provide a context for interpreting the level of variety occurring in the diet of registry participants, food group variety was compared between registry participants and 96 individuals who had recently participated in a behavioral weight loss program and had lost at least 7% of initial body weight. Results: Registry members reported consuming a diet with very low variety in all food groups, especially in those food groups higher in fat density. Registry participants consumed significantly (p < 0.001) less variety within all food groups, except fruit and combination foods, than recent weight losers after 6 months of weight loss treatment. Discussion: These results suggest that successful weight loss maintainers consume a diet with limited variety in all food groups. Restricting variety within all food groups may help with consuming a low‐energy diet and maintaining long‐term weight loss.     

Effects of elastic compression stockings on wall shear stress in deep and superficial veins of the calf

The purpose of this study was to estimate wall shear stress (WSS) in individual vessels of the venous circulation of the calf and quantify the effects of elastic compression based on change of vessel geometry and velocity waveform. The great saphenous vein and either a peroneal or posterior tibial vein have been imaged in four healthy subjects using magnetic resonance imaging, with and without the presence of a grade 1 medical stocking. Flow through image-based reconstructed geometries was numerically simulated for both a range of steady flow rates and ultrasound-derived transient velocity waveforms, scaled to give a standardized time averaged flow rate. For steady flow, the stocking produced an average percentage increase in mean WSS of approximately 100% in the great saphenous vein across a range of 0.125-1.25 ml/s. The percentage increase in the peroneal/posterior tibial veins varied from 490 to 650% across a range of 0.5-5 ml/s. In addition, application of the stocking eliminated periods of very low or zero flow from the transient waveforms. The average minimum value of WSS in all vessels without the stocking was <0.1 Pa. With the stocking, this was increased to 0.7 Pa in the great saphenous and 0.9 Pa in the peroneal/posterior tibial veins. The pathophysiological effects of these changes are discussed. In conclusion, the flight stocking was effective in raising venous WSS levels in prone subjects, and this effect was much more pronounced in the deep vessels. The stocking also tended to prevent cessation of flow during periods of increased downstream pressure produced by respiration.     

Sequential colonization by river periphyton analysed by microscopy and molecular fingerprinting

1. An artificial glass substratum was incubated in the River Danube for a period of 28 days in order to detect the sequential colonization of microorganisms.
2. Light and fluorescent microscopy showed that microalgae and the picoalgal fraction on the slides increased rapidly over the first 2 weeks of colonization. Diatoms were numerically the most abundant component of the periphyton and their species richness and diversity increased rapidly in the early phase of colonization whereas diversity subsequently increased moderately.
3. Evenness of the diatom community was initially high, lower in the intermediate phase and again higher later on. Succession involving early, intermediate and late colonizer species was observed. Community composition during the first 5 days of colonization was very different from later stages whereas there were only minor changes subsequently.
4. Molecular community analysis by means of terminal restriction fragment length polymorphism analysis of PCR amplified 16S rRNA and 18S rRNA genes pointed to even larger differences between the composition of samples obtained early and late in the period.
5. The number of 18S rRNA and 16S rRNA terminal restriction fragments (T-RF-s) was variable over the colonization period and the fragment patterns of both the bacterial and eukaryotic portion of the microbial community were variable, with most T-RF-s unique to a single sample, suggesting a wide diversity and dynamic properties of periphytic organisms.     

In vivo CRISPR screening reveals nutrient signaling processes underpinning CD8+ T cell fate decisions

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Effects of computer generated reminder charts on patients' compliance with drug regimens.

OBJECTIVE--To investigate whether a reminder chart improved patients'' compliance with their drug regimen after discharge from hospital. DESIGN--Patients were randomly allocated to one of four groups. Two groups received the reminder chart: one also received routine counselling from a nurse and the other received structured counselling from a pharmacist, which included an explanation of the reminder chart. The other two groups received only counseling, either from a nurse or from a pharmacist. Patients were visited about 10 days later: they were questioned about their drug regimen, and their compliance was measured by tablet counting. SETTING--The pharmacy in a district general hospital and patients'' homes. PATIENTS--197 patients being discharged from hospital who were regularly taking two or more drugs. INTERVENTION--An individualised reminder chart, which listed each person''s medicines and when they were to be taken and was automatically generated by a medicine labelling computer. MAIN OUTCOME MEASURES--Patient''s compliance with and knowledge of their drug regimen. MAIN RESULTS--Of the patients who received the reminder chart, 83% (95% confidence interval 74% to 90%) correctly described their dose regimen compared with 47% (37% to 58%) of those without the chart (p < 0.001). The mean compliance score was 86% (81% to 91%) in both groups not given the reminder chart; 91% (87% to 94%) in the group given the chart without an explanation; and 95% (93% to 98%) in the group given the chart and an explanation. A mean compliance score of > 85% was achieved by 63% (53% to 73%) of patients without a reminder chart and by 86% (78% to 93%) of those receiving the chart (p < 0.001). CONCLUSIONS--An automatically generated reminder chart is a practical and cost effective aid to compliance.     

Comparative abilities of lanthanide ions La3+ and Tb3+ to substitute for Ca2+ in regulating phospholipid-sensitive Ca2+-dependent protein kinase and myosin light chain kinase

Although lanthanide ions La³⁺ and Tb³⁺ were only slightly able to substitute for Ca²⁺ to activate phospholipid-sensitive Ca²⁺-dependent protein kinase (PL-Ca-PK), they potentiated the ability of a suboptimal concentration of Ca²⁺ to stimulate the enzyme. In comparison, the lanthanides were much more effective Ca²⁺ substitutes for myosin light chain kinase, a calmodulin-sensitive Ca²⁺-dependent protein kinase. Both enzymes, however, were inhibited by high concentrations of lanthanides either in the presence or absence of Ca²⁺. Similar effects of the lanthanides were also noted on phosphorylation of endogeneous substrates in the particulate fraction of rat brain stimulated by either phosphatidylserine/Ca²⁺ or calmodulin/Ca²⁺. The La³⁺- or Tb³⁺-stimulated activity of PL-Ca-PK, as the Ca²⁺-stimulated activity, was inhibited by various agents, such as trifluoperazine, polymyxin B, cobra cytotoxin I, melittin, and spermine.     

Purification to homogeneity, characterization and monoclonal antibodies of phospholipid-sensitive Ca2+-dependent protein kinase from spleen.

A phospholipid-sensitive Ca2+-dependent protein kinase was purified to homogeneity, for the first time, from extracts of pig spleen, employing the steps of DEAE-cellulose, octyl-agarose, Sephacryl S-200 and phosphatidylserine-Affigel 10 affinity chromatographies. The purified enzyme appeared as a single protein band on both analytical (non-denaturing) and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, having a minimum mol.wt. of 68 000 +/- 200. The molecular weight of the enzyme was also determined to be 74 500 +/- 4600 by gel filtration and 80 000 based on its sedimentation coefficient (5.52 S) and Stokes radius (3.52 +/- 0.09 nm), indicating that the enzyme was a monomeric protein. The frictional ratio (f/f0) of the enzyme was 1.24, indicating it was non-globular in shape. The enzyme had a pI of 5.3, and a pH optimum of 6.5 for its reaction. Amino acid analysis indicated that the enzyme apparently was not similar to myosin light-chain kinase (a calmodulin-sensitive species of Ca2+-dependent protein kinase) or cyclic AMP-dependent and cyclic GMP-dependent protein kinases. The enzyme had an apparent Km for ATP of 7.5 microns. Histone H1 and myelin basic protein were effective substrates for the enzyme, with apparent Km values of 0.3 and 0.2 microns, and Vmax, values of 0.06 and 0.09 mumol/min per mg of enzyme respectively. The enzyme activity was dependent on both phosphatidylserine (apparent Ka = 6.25 micrograms/ml) and Ca2+ (apparent Ka = 160 microns). Calmodulin was unable to substitute for the phospholipid as a cofactor, nor was it a subunit of the enzyme. Sr2+ and Ba2+ could partially mimic Ca2+ to activate the enzyme in the presence of phosphatidylserine. An endogenous substrate protein (mol.wt. 41 000) for the enzyme was found in the total, solubilized fraction of pig spleen. Monoclonal antibodies against the enzyme interacted similarly with the homogeneous and impure enzyme; the antibodies, however, did not bind to cyclic nucleotide-dependent protein kinases.     

Attachment of boar sperm to mucosal explants of oviduct in vitro: possible role in formation of a sperm reservoir

Ejaculated boar sperm were incubated with explants of porcine oviductal mucosa that had been dissected from the isthmic and ampullar regions of gilts. Sperm bound within minutes to the epithelial surfaces of the explants. Binding was not affected by region (isthmus or ampulla) nor day of estrous cycle (Day 0 or Day 10), but was increased by addition of 70 pg/ml 17 beta-estradiol to the medium. Scanning electron micrographs indicated that sperm bound, via the acrosomal region, to ciliated cells. After 24 h, the numbers of bound sperm dropped significantly, but the motility of the bound sperm did not. A mucous material that entrapped sperm was observed on the epithelial surfaces of 23/32 isthmic and only 4/32 ampullar explants. These results indicate that sperm sticking to ciliated cells and mucus can create a sperm reservoir in the isthmus, but the means by which sperm are released remain unknown.