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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   
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BACKGROUND AND PURPOSE:In the chronic phase after traumatic brain injury, DTI findings reflect WM integrity. DTI interpretation in the subacute phase is less straightforward. Microbleed evaluation with SWI is straightforward in both phases. We evaluated whether the microbleed concentration in the subacute phase is associated with the integrity of normal-appearing WM in the chronic phase.MATERIALS AND METHODS:Sixty of 211 consecutive patients 18 years of age or older admitted to our emergency department ≤24 hours after moderate to severe traumatic brain injury matched the selection criteria. Standardized 3T SWI, DTI, and T1WI were obtained 3 and 26 weeks after traumatic brain injury in 31 patients and 24 healthy volunteers. At baseline, microbleed concentrations were calculated. At follow-up, mean diffusivity (MD) was calculated in the normal-appearing WM in reference to the healthy volunteers (MDz). Through linear regression, we evaluated the relation between microbleed concentration and MDz in predefined structures.RESULTS:In the cerebral hemispheres, MDz at follow-up was independently associated with the microbleed concentration at baseline (left: B = 38.4 [95% CI 7.5–69.3], P = .017; right: B = 26.3 [95% CI 5.7–47.0], P = .014). No such relation was demonstrated in the central brain. MDz in the corpus callosum was independently associated with the microbleed concentration in the structures connected by WM tracts running through the corpus callosum (B = 20.0 [95% CI 24.8–75.2], P < .000). MDz in the central brain was independently associated with the microbleed concentration in the cerebral hemispheres (B = 25.7 [95% CI 3.9–47.5], P = .023).CONCLUSIONS:SWI-assessed microbleeds in the subacute phase are associated with DTI-based WM integrity in the chronic phase. These associations are found both within regions and between functionally connected regions.

The yearly incidence of traumatic brain injury (TBI) is around 300 per 100,000 persons.1,2 Almost three-quarters of patients with moderate to severe TBI have traumatic axonal injury (TAI).3 TAI is a major predictor of functional outcome,4,5 but it is mostly invisible on CT and conventional MR imaging.6,7DTI provides direct information on WM integrity and axonal injury.5,8 However, DTI abnormalities are neither specific for TAI nor stable over time. Possibly because of the release of mass effect and edema and resorption of blood products, the effects of concomitant (non-TAI) injury on DTI are larger in the subacute than in the chronic phase (>3 months).4,9,10 Therefore, DTI findings are expected to reflect TAI more specifically in the chronic than in the subacute phase (1 week–3 months).4 Even in regions without concomitant injury, the effects of TAI on DTI are dynamic, possibly caused by degeneration and neuroplastic changes.6,11,12 These ongoing pathophysiological processes possibly contribute to the emerging evidence that DTI findings in the chronic phase are most closely associated with the eventual functional outcome.12,13Although DTI provides valuable information, its acquisition, postprocessing, and interpretation in individual patients are demanding. SWI, with which microbleeds can be assessed with high sensitivity, is easier to interpret and implement in clinical practice. In contrast to DTI, SWI-detected traumatic microbleeds are more stable1 except in the hyperacute14,15 and the late chronic phases.16 Traumatic cerebral microbleeds are commonly interpreted as signs of TAI. However, the relation is not straightforward. On the one hand, nontraumatic microbleeds may be pre-existing. On the other hand, even if traumatic in origin, microbleeds represent traumatic vascular rather than axonal injury.17 Indeed, TAI is not invariably hemorrhagic.18 Additionally, microbleeds may secondarily develop after trauma through mechanisms unrelated to axonal injury, such as secondary ischemia.18DTI is not only affected by pathophysiological changes but also by susceptibility.19 The important susceptibility-effect generated by microbleeds renders the interpretation of DTI findings at the location of microbleeds complex. In the chronic phase, mean diffusivity (MD) is the most robust marker of WM integrity.4,6 For these reasons, we evaluated MD in the normal-appearing WM.Much TAI research focuses on the corpus callosum because it is commonly involved in TAI5,18,20 and it can reliably be evaluated with DTI,5,21 and TAI in the corpus callosum is related to clinical prognosis.6,20 The corpus callosum consists of densely packed WM tracts that structurally and functionally connect left- and right-sided brain structures.22 The integrity of the corpus callosum is associated with the integrity of the brain structures it connects.23 Therefore, microbleeds in brain structures that are connected through the corpus callosum may affect callosal DTI findings. Analogous to this, microbleeds in the cerebral hemispheres, which exert their function through WM tracts traveling through the deep brain structures and brain stem,24,25 may affect DTI findings in the WM of the latter.Our purpose was to evaluate whether the microbleed concentration in the subacute phase is associated with the integrity of normal-appearing WM in the chronic phase. We investigated this relation within the cerebral hemispheres and the central brain and between regions that are functionally connected by WM tracts.  相似文献   
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OBJECTIVES: In the quest for a cost-effective and quality-preserving solution to manage crowding in the emergency department, the possibility of deploying regular emergency nurses for the treatment of acute ankle injuries was investigated. The aim of this study is to compare the diagnostic accuracy of emergency nurses with that of senior house officers in interpreting ankle and foot radiographs. METHODS: A prospective study comparing the assessment of 60 radiographs (30 feet and 30 ankles) by 16 emergency nurses before and after an educational session was performed. Each subset of 30 radiographs contained 12 fractures, hand-picked by a radiologist to represent everyday traumatology in the emergency department. The control group consisted of eight senior house officers representing everyday expertise. The outcome of the diagnostic assessment, represented as the pooled sensitivity and specificity for both groups, was compared using Z-statistics. RESULTS: Before the training session, the specialized emergency nurse group showed a sensitivity of 0.87 (confidence interval 0.83-0.91) compared with 0.93 (confidence interval 0.88-0.96) for the control group (P = 0.05). The specificity of specialized emergency nurses was 0.87 (confidence interval 0.81-0.92) compared with 0.93 (confidence interval 0.89-0.95) for the senior house officers (P < 0.05). After the training session, specialized emergency nurse diagnostic parameters did not differ significantly from the control group, displaying a sensitivity of 0.89 (confidence interval 0.86-0.92) and specificity of 0.92 (confidence interval 0.87-0.95). CONCLUSION: Before the training session, the specialized emergency nurse group showed a significantly lower accuracy than the SHO group. After training, however, the diagnostic accuracy did not differ significantly between groups. Therefore, we conclude that emergency nurses are able to accurately interpret foot and ankle radiographs after a short educational session.  相似文献   
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SETTING: Diabetes mellitus is a known risk factor for tuberculosis (TB), but no studies have been reported from South-East Asia, which has a high burden of TB and a rapidly growing prevalence of diabetes. OBJECTIVE: To examine if and to what extent diabetes is associated with an increased risk of TB in an urban setting in Indonesia. DESIGN: Case-control study comparing the prevalence of diabetes mellitus (fasting blood glucose level >126 mg/dl) among newly diagnosed pulmonary TB patients and matched neighbourhood controls. RESULTS: Patients and control subjects had a similar age (median 30 years) and sex distribution (52% male), but malnutrition was more common among TB patients (median body mass index 17.7 vs. 21.5 kg/m2). HIV infection was uncommon (1.5% of patients). Diabetes mellitus was present in 60 of 454 TB patients (13.2%) and 18 of 556 (3.2%) control subjects (OR 4.7; 95%CI 2.7-8.1). Adjustment for possible confounding factors did not reduce the risk estimates. Following anti-tuberculosis treatment, hyperglycaemia reverted in a minority (3.7%) of TB patients. CONCLUSION: Diabetes mellitus is strongly associated with TB in young and non-obese subjects in an urban setting in Indonesia. This may have implications for TB control and patient care in this region.  相似文献   
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