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2.

Background

Early dumping is a poorly defined and incompletely understood complication after Roux-en-Y gastric (RYGB).

Objective

We performed a mixed-meal tolerance test in patients after RYGB to address the prevalence of early dumping and to gain further insight into its pathophysiology.

Setting

The study was conducted in a regional hospital in the northern part of the Netherlands.

Methods

From a random sample of patients who underwent primary RYGB between 2008 and 2011, 46 patients completed the mixed-meal tolerance test. The dumping severity score for early dumping was assessed every 30 minutes. A sum score at 30 or 60 minutes of ≥5 and an incremental score of ≥3 points were defined as indicating a high suspicion of early dumping. Blood samples were collected at baseline, every 10 minutes during the first half hour, and at 60 minutes after the start.

Results

The prevalence of a high suspicion of early dumping was 26%. No differences were seen for absolute hematocrit value, inactive glucagon-like peptide-1, and vasoactive intestinal peptide between patients with or without early dumping. Patients at high suspicion of early dumping had higher levels of active glucagon-like peptide-1 and peptide YY.

Conclusion

The prevalence of complaints at high suspicion of early dumping in a random population of patients after RYGB is 26% in response to a mixed-meal tolerance test. Postprandial increases in both glucagon-like peptide-1 and peptide YY are associated with symptoms of early dumping, suggesting gut L-cell overactivity in this syndrome.  相似文献   
3.

Objectives

Short successive periods of skeletal muscle disuse have been suggested to substantially contribute to the observed loss of skeletal muscle mass over the life span. Hospitalization of older individuals due to acute illness, injury, or major surgery generally results in a mean hospital stay of 5 to 7 days, during which the level of physical activity is strongly reduced. We hypothesized that hospitalization following elective total hip arthroplasty is accompanied by substantial leg muscle atrophy in older men and women.

Design and participants

Twenty-six older patients (75 ± 1 years) undergoing elective total hip arthroplasty participated in this observational study.

Measurements

On hospital admission and on the day of discharge, computed tomographic (CT) scans were performed to assess muscle cross-sectional area (CSA) of both legs. During surgery and on the day of hospital discharge, a skeletal muscle biopsy was taken from the m. vastus lateralis of the operated leg to assess muscle fiber type–specific CSA.

Results

An average of 5.6 ± 0.3 days of hospitalization resulted in a significant decline in quadriceps (?3.4% ± 1.0%) and thigh muscle CSA (?4.2% ± 1.1%) in the nonoperated leg (P < .05). Edema resulted in a 10.3% ± 1.7% increase in leg CSA in the operated leg (P < .05). At hospital admission, muscle fiber CSA was smaller in the type II vs type I fibers (3326 ± 253 μm2 vs 4075 ± 279 μm2, respectively; P < .05). During hospitalization, type I and II muscle fiber CSA tended to increase, likely due to edema in the operated leg (P = .10).

Conclusions

Six days of hospitalization following elective total hip arthroplasty leads to substantial leg muscle atrophy in older patients. Effective intervention strategies are warranted to prevent the loss of muscle mass induced by short periods of muscle disuse during hospitalization.  相似文献   
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Fluorescence in situ hybridization (FISH) was used to study numerical and structural chromosome 1 aberrations in interphase nuclei of transitional cell carcinomas (TCCs) of the urinary bladder. One of the characteristic numerical aberrations, as detected previously in low-grade noninvasive TCCs, included trisomy for chromosome 1 (A. H. N. Hopman et al., Cancer Res., 51: 644-651, 1991). We examined in more detail 22 cases with a centromeric (1q12) and a telomeric associated (1p36) DNA probe and with a library DNA probe from sorted human chromosome 1 in single- and double-target FISH procedures. All flow cytometrically determined DNA diploid TCCs (13 cases), which showed three spots for 1q12 (6 cases), had two spots for 1p36. Since the library DNA probe showed three separate domains in the nuclei of these cases, the additional copy for 1q12 could be explained as an extra chromosome 1p-, containing the 1q12 target. In the flow cytometrically determined DNA tetraploid/aneuploid tumors, the results were more complex. In 6 of 9 cases, we observed an overrepresentation of 1q12 as compared to 1p36, also suggesting the presence of extra copies of 1p- chromosomes. The results of the present study demonstrate the utility of the FISH method to assess structural chromosome aberrations in interphase nuclei of solid tumors.  相似文献   
6.
Summary It has been suggested that the reduced resistance of patients with rheumatoid arthritis (RA) to bacterial joint infections may be due in part to polymorphonuclear cell (PMN) function. To obtain further insight into the mechanis that contribute to the increased susceptiblity of RA patients to such infections we investigated the influence of different solid surfaces on the ingestion of various bacterial strains by PMN. Both in the presence and absence of serum, phagocytosis of bacteria by PMN was significantly lower on monolayers of synovial fibroblasts as compared to monolayers of endothelial cells and embryonic fibroblasts. It could be shown that the relative influence of the solid surfac on the results of the phagocytosis assay increased when decreasing concentrations of purified IgG were used. The results of this study sugpurified IgG were used. The results of this study suggested that the effect of synovial fibroblasts on PMB may lead to reduced clearance of bacteria from the joint.  相似文献   
7.
Background: The effects of tailored intervention on multiple behaviors and possible moderators of tailoring effects have not yet been sufficiently demonstrated.Purpose: The purpose of this study was to examine the effectiveness of a computer-tailored intervention on smoking; physical activity; and fruit, vegetable, and fat intake; and to test potential moderators of the effectiveness (BMI, age, SES, gender, motivation, and the number of behaviors for which respondents met the recommendations from national guidelines).Methods: Respondents were randomly assigned to a tailored intervention group, receiving one tailored letter on all of these behaviors, or a control intervention group, receiving one general information letter on all behaviors.Results: Three months after the baseline assessment, the tailored intervention group showed significantly better effects than the control group for all behaviors studied, except for smoking. Notably, the intervention did not enhance the health behaviors, but rather reduced a decline in these behaviors during the 3-month study interval. Effect sizes were small. No moderating factors were found, except for the number of behaviors for which recommendations were met in the tailoring intervention group on fruit consumption. The largest effects of the tailored intervention were found for fruit in respondents who did not meet the recommendations for any behavior (Cohen’s d=0.3).Conclusions: A tailored intervention on multiple behaviors had significant, but limited effects when compared to generic information. The number of bad habits influenced the effects of the tailored intervention on fruit consumption.  相似文献   
8.
In a randomized, double-blind, crossover cumulative study, the individual maximal bronchodilator dosages for formoterol (F) and salbutamol (S) were assessed for their respective influence on ECG, pulse rate, and serum potassium levels in 13 patients with stable and reversible asthma. The following dosages were administered with an interval of 1 h: 12-24-48-(48)-(48) micrograms for F and 100-200-400-400-(400)-(400) micrograms for S. The study day was discontinued if pulse rate was above 140 beats min-1, a flattening of T wave on the ECG was recorded, or a maximal bronchodilation in FEV1 was observed (above 110 percent of the predicted value or an increase in FEV1 in the last two measurements below 5 percent). The maximal individual dose of F administered was 84 micrograms in six patients, 132 micrograms in three patients, 180 micrograms in three patients, and 228 micrograms in one patient. For S, the maximal individual dose was 400 micrograms in three patients, 2,200 micrograms in eight patients, 3,000 micrograms in one patient, and 3,800 micrograms in one patient. The mean maximal increase in FEV1 was 36.0 percent after F and 35.1 percent after S. Pulse rate increased from 73 to S3 beats.min-1 after F and from 75 to 84 beats.min-1 after S (both statistically significant). No pulse rate above 140 beats.min-1 was observed. In the high-therapeutic range (up to 36 micrograms of F and 6,090 micrograms of S), no changes in potassium level were observed. In still higher dosages, mean potassium level decreased from 4.16 to 3.78 mmol.L-1 after F and from 4.02 to 3.88 mmol.L-1 after S (not clinically relevant). The lowest individual potassium level recorded was 3.1 mmol.L-1. No clinically important changes in ECG were observed. In conclusion, very high doses of F and S administered from a metered dose inhaler proved to be safe for patients.  相似文献   
9.
Forty transitional cell carcinomas of the human urinary bladder (TCCs) were examined for numerical aberrations of chromosomes 1, 7, 9, and 11 by in situ hybridization using chromosome-specific probes. Our interphase cytogenetic study of 24 low-grade, noninvasive TCCs, which were near-diploid by flow cytometry, showed a numerical aberration for at least 1 of these chromosomes in 14 of these cases. Most strikingly, a monosomy for chromosome 9 was found in 9 of 24 low-grade TCCs. A trisomy for chromosomes 1, 7, and 11 was detected in 5, 2, and 1 case(s), respectively. In 1 case a monosomy for chromosome 1 was detected by in situ hybridization. Monosomy for chromosome 9 was the only detected numerical change in 5 low-grade TCC cases. Examination of 16 invasive TCCs showed extra copies for chromosomes 1 and 7 in 7 flow cytometrically diploid cases with numerical chromosome aberrations; also, loss of chromosome 9 was detected. In 5 invasive and 2 noninvasive aneuploid/tetraploid TCCs a profound imbalance between the different chromosomes was found. In 5 of these cases an evident underrepresentation of chromosome 9 in comparison to chromosomes 1, 7, and 11 was detected. This underrepresentation of chromosome 9 in diploid, as well as aneuploid, TCCs, and in some cases the constant ratio between this chromosome and the other chromosomes, may be explained by a process of tetraploidization. Therefore, loss of chromosome 9 may be one of the primary genetic events in TCC oncogenesis, with secondary events, such as tetraploidization, correlated to tumor progression. Our results show that in situ hybridization can be routinely used to study important cytogenetic changes which occur during the development of a malignant disease.  相似文献   
10.
We have re-examined an extended myotonic dystrophy (DM) family, previously described in 1955, in order to study the long term effects of anticipation in DM and in particular the implications for families affected by this disease. This follow up study provides data on 35 gene carriers and 46 asymptomatic at risk family members in five generations. Clinical anticipation, defined as the cascade of mild, adult, childhood, or congenital disease in subsequent generations, appeared to be a relentless process, occurring in all affected branches of the family. The cascade was found to proceed asynchronously in the different branches, mainly because of an unequal number of generations with mild disease. The transition from the mild to the adult type was associated with transmission through a male parent. Stable transmission of the asymptomatic/mild phenotype showed a female transmission bias. We further examined the extent and causes of gene loss in this pedigree. Gene loss in the patient group was complete, owing to infertility of the male patients with adult onset disease and the fact that mentally retarded patients did not procreate. Out of the 46 at risk subjects in the two youngest generations, only one was found to have a full mutation. This is the only subject who may transmit the gene to the sixth generation. No protomutation carriers were found in the fourth and fifth generations. Therefore it is highly probable that the DM gene will be eliminated from this pedigree within one generation. The high population frequency of DM can at present not be explained by the contribution of asymptomatic cases in the younger generations of known families, but is probably caused by the events in the ancestral generations.  相似文献   
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