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Functional studies of how duodenal–jejunal exclusion (DJE) brings a superior glycemic control when added to sleeve gastrectomy in duodenal–jejunal bypass with sleeve gastrectomy (DJB-SG) patients, are lacking. To study this, we compared the appetite sensations and the β-cell response following a standard mixed meal in patients with DJB-SG, versus those with sleeve gastrectomy (SG) alone. Twenty one patients who underwent DJB-SG and 25 with SG, who participated in mixed-meal tests (MMTT) preoperatively and at 1 year, with complete data were included and compared. Blood glucose, C-peptide, and insulin levels were estimated, along with the visual analogue scale (VAS) scoring of the six appetite sensations, as a part of the MMTT. At 1 year following surgery, compared to SG group, DJB-SG group had greater complete remission rates (HbA1C

Formal surface devices at syntactic, prosodic, and semantic levels may converge, compete, or conspire with each other for specific meanings/functions assignment, such as given and new interpretation. Studies based on the Competition Model have shown that form–function mappings are assigned different strengths determined by the statistical distributions of certain attributes of the cues, depending on language structure. In view of the qualitative and quantitative differences between Mandarin Chinese and English, this comparative study, by adopting a verification task, investigates the similarities and differences in the utilization of the surface cues of word order, marked cleft structure, animacy, and focal accent between the two languages for given and new interpretation within an isolated sentence. Forty Taiwanese Mandarin and American English adult speakers, each with 20, were asked to verify a stimulus sentence against a pair of pictures to measure their interpretation of the given and new distinctions implied in a particular stimulus. The results showed that the hierarchy of cue strength in Mandarin Chinese, in descending order, was word order, animacy, focal accent, and cleft, while that in English was cleft, word order, focal accent, and animacy. The findings support the interactive constraint-based view of pragmatic processing, and reveal cross-linguistic variations, which were explored from typological, psycholinguistic, and information patterning perspectives.

Glucose has long been considered the substrate for energy metabolism in the retina. Recently, an alternative hypothesis (metabolic coupling) suggested that mitochondria in retinal neurons utilize preferentially the lactate produced specifically by Müller cells, the principal glial cell in the retina. These two views of retinal metabolism were examined using confluent cultures of photoreceptor cells, Müller cells, ganglion cells, and retinal pigment epithelial cells incubated in modified Dulbecco's minimal essential medium containing glucose or glucose and lactate. The photoreceptor and ganglion cells represented neural elements, and the Müller and pigment epithelial cells represented non-neural cells. The purpose of the present experiments was two-fold: (1) to determine whether lactate is a metabolic product or substrate in retinal cells, and (2) to examine the evidence that supports the two views of retinal energy metabolism. Measurements were made of lactic acid production, cellular ATP levels, and cellular morphology over 4 h. Results showed that all cell types incubated with 5 mM glucose produced lactate aerobically and anaerobically at linear rates, the anaerobic rate being 2-3-fold higher (Pasteur effect). Cells incubated with both 5 mM glucose and 10 mM lactate produced lactate aerobically and anaerobically at rates similar to those found when cells were incubated with glucose alone. Anaerobic ATP content in the cells was maintained at greater than 50% of the control, aerobic value, and cellular morphology was well preserved under all conditions. The results show that the cultured retinal cells produce lactate, even in the presence of a high starting ambient concentration of lactate. Thus, the net direction of the lactic dehydrogenase reaction is toward lactate formation rather than lactate utilization. It is concluded that retinal cells use glucose, and not glial derived lactate, as their major substrate.

Inherited defects in the RDS gene cause a multiplicity of progressive retinal diseases in humans. The gene product, peripherin/rds (P/rds), is a member of the tetraspanin protein family required for normal vertebrate photoreceptor outer segment (OS) architecture. Although its molecular function remains uncertain, P/rds has been suggested to catalyze membrane fusion events required for the OS renewal process. This study investigates the importance of two charged residues within a predicted C-terminal helical region for protein biosynthesis, localization, and interaction with model membranes. Targeted mutagenesis was utilized to neutralize charges at Glu(321) and Lys(324) individually and in combination to generate three mutant variants. Studies were conducted on variants expressed as 1) full-length P/rds in COS-1 cells, 2) glutathione S-transferase fusion proteins in Escherichia coli, and 3) membrane-associated green fluorescent protein fusion proteins in transgenic Xenopus laevis. None of the mutations affected biosynthesis of full-length P/rds in COS-1 cells as assessed by Western blotting, sedimentation velocity, and immunofluorescence microscopy. Although all mutations reside within a recently identified localization signal, none altered the ability of this region to direct OS targeting in transgenic X. laevis retinas. In contrast, individual or simultaneous neutralization of the charged amino acids Glu(321) and Lys(324) abolished the ability of the C-terminal domain to promote model membrane fusion as assayed by lipid mixing. These results demonstrate that, although overlapping, C-terminal determinants responsible for OS targeting and fusogenicity are separable and that fusogenic activity has been uncoupled from other protein properties. The observation that subunit assembly and OS targeting can both proceed normally in the absence of fusogenic activity suggests that properly assembled and targeted yet functionally altered proteins could potentially generate pathogenic effects within the vertebrate photoreceptor.