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51.

Aims

Evidence of ethnic disparities in the conversion of prediabetes to type 2 diabetes is scarce. We studied the association of impaired fasting glucose (IFG) and fasting plasma glucose (FPG) with the 10-year cumulative incidence of type 2 diabetes in three ethnic groups.

Methods

We analyzed data for 90 South-Asian Surinamese, 190 African-Surinamese, and 176 ethnic Dutch that were collected in the periods 2001–2003 and 2011–2012. We excluded those with type 2 diabetes or missing FPG data. We defined baseline IFG as FPG of 5.7–6.9 mmol/L. We defined type 2 diabetes at follow-up as FPG ≥ 7.0 mmol/L, HbA1c ≥ 48 mmol/mol (6.5%), or self-reported type 2 diabetes.

Results

10-Year cumulative incidences of type 2 diabetes were: South-Asian Surinamese, 18.9%; African-Surinamese, 13.7%; ethnic Dutch, 4.5% (p < 0.05). The adjusted association of baseline IFG and FPG with the 10-year cumulative incidence of type 2 diabetes was stronger for South-Asian Surinamese than for African-Surinamese and ethnic Dutch. The IFG (compared to normoglycaemia) ORs were 11.1 [3.0–40.8] for South-Asian Surinamese, 5.1 [2.0–13.3] for African-Surinamese, and 2.2 [0.5–10.1] for ethnic Dutch.

Conclusions

The 10-year cumulative incidence of type 2 diabetes was higher and associations with baseline IFG and FPG were stronger among South-Asian Surinamese and African-Surinamese than among ethnic Dutch. Our findings confirm the high risk of type 2 diabetes in South-Asians and suggest more rapid conversion in populations of South-Asian origin and (to a lesser extent) African origin than European origin.  相似文献   
52.
Microstructural white matter deterioration is a frequent finding in mild cognitive impairment (MCI), potentially underlying default mode network (DMN) dysfunctioning. Thus far, microstructural damage in MCI has been attributed to Alzheimer's disease pathophysiology. A cerebrovascular role, in particular the role of cerebral small vessel disease (CSVD), received less interest. Here, we used diffusion tensor imaging (DTI) to examine the role of CSVD in microstructural deterioration within the normal appearing white matter (NAWM) in MCI. MCI patients were subdivided into those with (n = 20) and without (n = 31) macrostructural CSVD evidence on MRI. Using TBSS we performed microstructural integrity comparisons within the whole brain NAWM. Secondly, we segmented white matter tracts interconnecting DMN brain regions by means of automated tractography segmentation. We used NAWM DTI measures from these tracts as dependent variables in a stepwise‐linear regression analysis, with structural and demographical predictors. Our results indicated microstructural deterioration within the anterior corpus callosum, internal and external capsule and periventricular white matter in MCI patients with CSVD, while in MCI patients without CSVD, deterioration was restricted to the right perforant path, a tract along the hippocampus. Within the full cohort of MCI patients, microstructure within the NAWM of the DMN fiber tracts was affected by the presence of CSVD. Within the cingulum along the hippocampal cortex we found a relationship between microstructural integrity and ipsilateral hippocampal volume and the extent of white matter hyperintensity. In conclusion, we found evidence of CSVD‐related microstructural damage in fiber tracts subserving the DMN in MCI. Hum Brain Mapp 35:2836–2851, 2014. © 2013 Wiley Periodicals, Inc .  相似文献   
53.

Background

Computer-assisted decision support is an emerging modality to assist patients with type 2 diabetes mellitus (T2DM) in insulin self-titration (ie, self-adjusting insulin dose according to daily blood glucose levels). Computer-assisted insulin self-titration systems mainly focus on helping patients overcome barriers related to the cognitive components of insulin titration. Yet other (eg, psychological or physical) barriers could still impede effective use of such systems.

Objective

Our primary aim was to identify experiences with and barriers to self-monitoring of blood glucose, insulin injection, and insulin titration among patients with T2DM. Our research team developed a computer-assisted insulin self-titration system, called PANDIT. The secondary aim of this study was to evaluate patients’ perceptions of computer-assisted insulin self-titration. We included patients who used PANDIT in a 4-week pilot study as well as patients who had never used such a system.

Methods

In-depth, semi-structured interviews were conducted individually with patients on insulin therapy who were randomly recruited from a university hospital and surrounding general practices in the Netherlands. The interviews were transcribed verbatim and analyzed qualitatively. To classify the textual remarks, we created a codebook during the analysis, in a bottom-up and iterative fashion. To support examination of the final coded data, we used three theories from the field of health psychology and the integrated model of user satisfaction and technology acceptance by Wixom and Todd.

Results

When starting insulin therapy, some patients feared a lifelong commitment to insulin therapy and disease progression. Also, many barriers arose when implementing insulin therapy (eg, some patients were embarrassed to inject insulin in public). Furthermore, patients had difficulties increasing the insulin dose because they fear hypoglycemia, they associate higher insulin doses with disease progression, and some were ignorant of treatment targets. Patients who never used a computer-assisted insulin self-titration system felt they had enough knowledge to know when their insulin should be adjusted, but still believed that the system advice would be useful to confirm their reasoning. Furthermore, the time and effort saved with automated insulin advice was considered an advantage. Patients who had used PANDIT found the system useful if their glycemic regulation improved. Nevertheless, for some patients, the absence of personal contact with their caregiver was a drawback. While guidelines state that adjustment of basal insulin dose based on fasting plasma glucose values is sufficient, both patients who had and those who had not used PANDIT felt that such a system should take more patient data into consideration, such as lifestyle and diet factors.

Conclusions

Patients encounter multiple obstacles when implementing insulin therapy. Computer-assisted insulin self-titration can increase patient awareness of treatment targets and increase their confidence in self-adjusting the insulin dose. Nevertheless, some barriers may still exist when using computer-assisted titration systems and these systems could also introduce new barriers.  相似文献   
54.
Social Psychiatry and Psychiatric Epidemiology - Our study explored whether aspects of veterans’ social connectedness (social support, interpersonal conflict, loneliness, social norms, number...  相似文献   
55.
Evidence on survival of malignant mesothelioma (MM) and other rare thoracic cancers is limited due to the rarity of these cancer sites. Here, we provide a comprehensive overview of MM incidence and survival after MM and other rare thoracic cancers in Germany and the United States (US). Incidence was estimated from a German National Cancer Database and from the Surveillance, Epidemiology and End Results (SEER) 18 database for 2000–2014. Patients diagnosed in 1997–2013 with malignant epithelial tumors of the trachea (Etra), epithelial tumors of the thymus (Ethy) and MM were extracted from a German cancer survival database and from the SEER 13 database. Period analysis was employed to compute 5-year relative survival (RS). During 2000–2014, an annual average of 0.9 and 0.6 MM cases per 100,000 person-years was diagnosed in Germany and the US. Rates decreased in Germany and in the US. Patients with Ethy had highest 5-year RS with US patients surviving longer (69.1% compared to 63.7%, p = 0.02). Survival after Etra was comparable in both countries (Germany 33.6%, US 34.4%, p = 0.07). Survival in MM patients was poor overall (Germany 11.8%, US 12.1%, p < 0.01). Survival improvements were only observed in MM patients in Germany (10.8% [2002–2007] vs. 13.0% [2008–2013], p < 0.01). The lack of progress in survival for Etra and Ethy patients underlines the need of novel preventive, therapeutic and diagnostic approaches. MM incidence significantly decreased in Germany and in the US. Further monitoring of MM incidence is warranted given that a peak in incidence is expected in 2020–2030 in Western countries.  相似文献   
56.
Copy number gains and increased expression levels of cellular Inhibitor of Apoptosis protein (cIAP)1 and cIAP2 have been identified in primary diffuse large B-cell lymphoma (DLBCL) tissues. Second mitochondria-derived activator of caspases (Smac) mimetics were designed to antagonize IAP proteins. However, since their effect as single agents is limited, combination treatment represents a strategy for their clinical development. Therefore, we investigated the Smac mimetic BV6 in combination with proteasome inhibitors and analyzed the molecular mechanisms of action. We discovered that BV6 treatment sensitizes DLBCL cells to proteasome inhibition. We show a synergistic decrease in cell viability and induction of apoptosis by BV6/Carfilzomib (CFZ) treatment, which was confirmed by calculation of combination index (CI) and Bliss score. BV6 and CFZ acted together to trigger activation of BAX and BAK, which facilitated cell death, as knockdown of BAX and BAK significantly reduced BV6/CFZ-mediated cell death. Activation of BAX and BAK was accompanied by loss of mitochondrial membrane potential (MMP) and activation of caspases. Pretreatment with the caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (zVAD.fmk) rescued BV6/CFZ-induced cell death, confirming caspase dependency. Treatment with CFZ alone or in combination with BV6 caused accumulation of NOXA, which was required for cell death, as gene silencing by siRNA or Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9-mediated NOXA inactivation inhibited BV6/CFZ-induced cell death. Together, these experiments indicate that BV6 and CFZ cooperatively induce apoptotic cell death via the mitochondrial pathway. These findings emphasize the role of Smac mimetics for sensitizing DLBCL cells to proteasome inhibition with important implications for further (pre)clinical studies.  相似文献   
57.
Neuropeptide Y receptor expression in human primary ovarian neoplasms   总被引:2,自引:0,他引:2  
Peptide hormone receptors overexpressed in human malignant neoplasms are potential targets for diagnostic scintigraphy and radiotherapy. One such receptor is the neuropeptide Y (NPY) receptor, mediating primarily feeding behavior in the brain but shown recently to play a role in breast cancer. In this study, the presence of NPY receptors was evaluated in another group of gynecological tumors, namely ovarian tumors, using in vitro receptor autoradiography with (125)I-labeled peptide YY and receptor subtype selective analogs. Remarkably, all 10 investigated inhibin-expressing granulosa cell tumors, Leydig cell tumors, and Sertoli-Leydig cell tumors expressed NPY receptors. In contrast, receptors were found in only seven of 22 ovarian adenocarcinomas (32%). Pharmacological characterization of the expressed NPY receptor subtypes in the various tumors revealed the presence of Y1, Y2, or both. In addition, Y1 receptors were observed in intra- and peritumoral blood vessels as well. NPY receptors were not expressed in three ovarian adenomas, three borderline tumors, four fibromas and fibrothecomas, and one dysgerminoma. This is the first time that NPY receptors are described in human ovarian tissue. They may play a role in the pathogenesis and also in the pathophysiology of ovarian malignancies. Moreover, the high incidence and density of NPY receptors in sex cord-stromal tumors suggest that these receptors represent a new potential target for the diagnostic and therapeutic administration of NPY analogs in these tumors.  相似文献   
58.

Objective

Autologous therapy via stem cell-based tissue regeneration is an aim to rebuild natural teeth. One option is the use of adult stem cells from the dental pulp (DPSCs), which have been shown to differentiate into several types of tissue in vitro and in vivo, especially into tooth-like structures. DPSCs are mainly isolated from the dental pulp of third molars routinely extracted for orthodontic reasons. Due to the extraction of third molars at various phases of life, DPSCs are isolated at different developmental stages of the tooth.

Design

The present study addressed the question whether DPSCs from patients of different ages were similar in their growth characteristics with respect to the stage of tooth development. Therefore DPSCs from third molars of 12–30 year-old patients were extracted, and growth characteristics, e.g. doubling time and maximal cell division potential were analysed. In addition, pulp and hard dental material weight were recorded.

Results

Irrespective of the age of patients almost all isolated cells reached 40–60 generations with no correlation between maximal cell division potential and patient age. Cells from patients <22 years showed a significantly faster doubling time than the cells from patients ≥22 years.

Conclusion

The age of patients at the time of stem cell isolation is not a crucial factor concerning maximal cell division potential, but does have an impact on the doubling time. However, differences in individuals regarding growth characteristics were more pronounced than age-dependent differences.  相似文献   
59.
60.
Objectives: Although the aortic-valve-sparing (AVS) reimplantation technique according to David has shown favorable durability results in mid-term and long-term studies, composite valve grafting (CVG) according to Bentall is still considered the standard procedure. Methods: Retrospectively, we evaluated the results of aortic root replacement of patients with Marfan syndrome (MFS) who underwent surgery between January 1995 and January 2010. MFS was diagnosed using the Ghent criteria. AVS was used in 58 patients and CVG in 30 patients with MFS. AVS was done for aortic-root aneurysm (n = 48) or aortic dissection type A (n = 10). CVG was used for aortic-root aneurysm in 14 patients or aortic dissection type A in 16 patients. The mean follow-up was 3.2 (95% CI: 2.4–4.2) years. Results: In both groups, 30-day mortality was 0%. Three patients (10.0%) in the CVG group required resternotomy for postoperative bleeding versus two patients (3.4%) in the AVS group (p = 0.3). At follow-up, mortality was 10% in the CVG group versus 3.4% in the AVS group (p = 0.3). Re-operation was required in two patients (3.4%) after AVS and in three patients after CVG (10%) (p = 0.3). Three patients (10.0%) who underwent CVG had endocarditis and two patients (6.7%) had a stroke during follow-up, whereas no endocarditis and stroke occurred after AVS. After 14 years, stratified event-free survival was better in the AVS group (event-free survival was 82.3% vs 58.6%, log-rank test p = 0.086), especially after aneurysm (p = 0.057). After 10 years, freedom from aortic regurgitation ≥II° in the AVS group was 80% for aneurysm and 50% after dissection (p = 0.524). Conclusion: The reimplantation technique according to David was associated with excellent survival, good valve function and a low rate of re-operation, endocarditis, and stroke. There was a trend to better event-free survival for AVS patients making it the procedure of choice in MFS patients.  相似文献   
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