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91.
STUDY OBJECTIVES: Relapse-free survival in patients with sulcus superior tumors. DESIGN: Prospective registration study. SETTING: Department of surgical oncology of a university hospital. PATIENTS: Twenty-one patients treated with preoperative radiotherapy (46 Gy), lobectomy and chest-wall resection, and intraoperative radiotherapy (10 Gy). RESULTS: After a median follow-up of 18 months, 18 patients (85%) were free from locoregional relapse, while 8 patients were still alive. CONCLUSIONS: The results show that this protocol can achieve excellent local tumor control and can even be used for palliative treatment.  相似文献   
92.
A kindred was diagnosed with atypical MEN type 2B characterized by medullary thyroid cancer and mucosal neurilemmomas in multiple family members. Mutation analysis revealed a double RET germline mutation, Val804Met and Ser904Cys, in affected individuals. The clinical phenotype, the functional effect of the mutations, and the clinical implications of our findings are discussed.  相似文献   
93.
OBJECTIVE: Arterial remodeling aims to maintain a constant circumferential wall stress (sigmac). A failing remodeling process is associated with stroke. Data on the relationship between chronic kidney disease and arterial remodeling are scarce. METHODS: We investigated the association between a lower glomerular filtration rate (GFR) and microalbuminuria with arterial remodeling of the common carotid artery (CCA) in a population-based study of 806 patients. CCA properties including intima-media thickness and interadventitial diameter (IAD) were assessed. Lumen diameter, circumferential wall tension (CWT), and circumferential wall stress (sigmac) were calculated. GFR was estimated (eGFR) by the Modification of Diet in Renal Disease formula. Albuminuria was expressed as urinary albumin/creatinine ratio. RESULTS: Mean eGFR was 60.3 (+/-10.8) ml/min/1.73 m2; median urinary albumin/creatinine ratio was 0.57 (range 0.10-26.6 mg/mmol). After adjustment for age, sex, glucose tolerance status, and prevalent cardiovascular disease, eGFR was not independently associated with CCA properties. A greater urinary albumin/creatinine ratio (per quartile) was associated with a greater lumen diameter [regression coefficient beta with 95% confidence interval, 0.14 (0.08-0.20; P < 0.01)], IAD [0.15 (0.09-0.21; P < 0.01)], CWT [0.95 (0.52-1.38; P < 0.01)], and sigmac [1.7 (0.5-2.9; P < 0.01)] but not with a greater IMT [0.01 (-0.002-0.02; P = 0.12)]. Additional adjustments for mean arterial pressure, pulse pressure, and eGFR did not change the results. CONCLUSION: Greater albuminuria is independently associated with an increase in lumen diameter and IAD of the CCA. In addition, greater albuminuria is associated with a maladaptive carotid remodeling process as shown by an increase in CWT and sigmac. These findings may explain, why microalbuminuria is associated with a greater risk of cardiovascular disease and especially stroke.  相似文献   
94.
CC10 (CC16, uteroglobin) is a pulmonary protein postulated to play a counter regulatory role in sarcoidosis pathogenesis. The adenine38guanine (A38G) polymorphism of the encoding CC10 gene (SCGB1A1) is functional. Recently, an association between the low CC10 producing 38A allele and sarcoidosis susceptibility has been reported in Japanese patients from Hokkaido. The aim of the present study was to confirm this association in a clinically well characterized population of Dutch white and Kyoto Japanese patients with sarcoidosis and control subjects. No difference in genotype or allele frequency was found between patients with sarcoidosis and control subjects in either ethnic population. Remarkably, however, a significant difference was found between the control subjects from Kyoto and Hokkaido, but not between the Japanese groups of patients with sarcoidosis. Furthermore, review of previously published A38G genotyping results showed a consistent difference in CC10 A38G allele frequencies between whites and Japanese subjects. We conclude that the CC10 A38G polymorphism does not influence sarcoidosis susceptibility in Dutch whites or in Japanese subjects from Kyoto. This stresses the importance of studying the influence of polymorphisms on disease susceptibility in multiple ethnically and geographically distinct disease and control populations before reaching conclusions.  相似文献   
95.
Genetic and environmental control of host-gut microbiota interactions   总被引:1,自引:0,他引:1  
Genetics provides a potentially powerful approach to dissect host-gut microbiota interactions. Toward this end, we profiled gut microbiota using 16s rRNA gene sequencing in a panel of 110 diverse inbred strains of mice. This panel has previously been studied for a wide range of metabolic traits and can be used for high-resolution association mapping. Using a SNP-based approach with a linear mixed model, we estimated the heritability of microbiota composition. We conclude that, in a controlled environment, the genetic background accounts for a substantial fraction of abundance of most common microbiota. The mice were previously studied for response to a high-fat, high-sucrose diet, and we hypothesized that the dietary response was determined in part by gut microbiota composition. We tested this using a cross-fostering strategy in which a strain showing a modest response, SWR, was seeded with microbiota from a strain showing a strong response, A×B19. Consistent with a role of microbiota in dietary response, the cross-fostered SWR pups exhibited a significantly increased response in weight gain. To examine specific microbiota contributing to the response, we identified various genera whose abundance correlated with dietary response. Among these, we chose Akkermansia muciniphila, a common anaerobe previously associated with metabolic effects. When administered to strain A×B19 by gavage, the dietary response was significantly blunted for obesity, plasma lipids, and insulin resistance. In an effort to further understand host-microbiota interactions, we mapped loci controlling microbiota composition and prioritized candidate genes. Our publicly available data provide a resource for future studies.Studies carried out over the last decade have revealed that gut microbiota contribute to a variety of common disorders, including obesity and diabetes (Musso et al. 2011), colitis (Devkota et al. 2012), atherosclerosis (Wang et al. 2011), rheumatoid arthritis (Vaahtovuo et al. 2008), and cancer (Yoshimoto et al. 2013). The evidence for metabolic interactions is particularly strong, as a large body of data now supports the conclusion that gut microbiota influence the energy harvest from dietary components, particularly complex carbohydrates, and that metabolites such as the short-chain fatty acids produced by gut bacteria can perturb metabolic traits, including adiposity and insulin resistance (Turnbaugh et al. 2006, 2009; Backhed et al. 2007; Wen et al. 2008; Ridaura et al. 2013). Gut microbiota communities are assembled each generation, influenced by maternal seeding, environmental factors, host genetics, and age, resulting in substantial variations in composition among individuals in human populations (Eckburg et al. 2005; Costello et al. 2009; Human Microbiome Project Consortium 2012; Goodrich et al. 2014). Most experimental studies of host-gut microbiota interactions have employed large perturbations, such as comparisons of germ-free versus conventional mice, and the significance of common variations in gut microbiota composition for disease susceptibility is still poorly understood. Furthermore, while studies with germ-free mice have clearly implicated microbiota in clinically relevant traits, it has proven difficult to identify the responsible taxa of bacteria.We now report a population-based analysis of host-gut microbiota interactions in the mouse. One of the issues we explore is the role of host genetics. Although some evidence is consistent with significant heritability of gut microbiota composition, the extent to which the host controls microbiota composition under controlled environmental conditions is unclear. We also examined the role of common variations in gut microbiota in metabolic traits such as obesity and insulin resistance and mapped loci contributing to the abundance of certain microbiota. We performed our study using a resource termed the Hybrid Mouse Diversity Panel (HMDP), consisting of about 100 inbred strains of mice that have been either sequenced or subjected to high-density genotyping (Bennett et al. 2010). The resource has several advantages for genetic analysis as compared to traditional genetic crosses. First, it allows high-resolution mapping by association rather than linkage analysis, and it has now been used for the identification of a number of novel genes underlying complex traits (Farber et al. 2011; Lavinsky et al. 2015; Parks et al. 2015; Rau et al. 2015). Second, since the strains are permanent, the data from separate studies can be integrated, allowing the development of large, publicly available databases of physiological and molecular traits relevant to a variety of clinical disorders (systems.genetics.ucla.edu and phenome.jax.org). Third, the panel is ideal for examining gene-by-environment interactions, since it is possible to examine individuals of a particular genotype under a variety of conditions (Orozco et al. 2012; Parks et al. 2013).  相似文献   
96.

Background

Cardiac rehabilitation (CR) exercise training is beneficial after myocardial infarction (MI). Whilst the peripheral adaptations to training are well defined, little is known regarding the effect on left ventricular (LV) remodelling, particularly LV function. Efficient LV ejection and filling is achieved through deformation and rotation of the myocardium in systole and diastole – LV mechanics. The response of LV mechanics to CR exercise training in MI patients is unknown.

Methods

In this observational exploratory study, 36 (of 40 enrolled) male, MI patients completed either 10-weeks of twice-weekly gym based cardiovascular exercise at 60–80% VO2peak (n = 18), or a non-exercise control period (n = 18). Cardiopulmonary exercise testing and speckle tracking echocardiography were performed at baseline and 10 weeks.

Results

Compared to the non-exercise group, VO2peak improved with CR exercise training (Difference: +4.28 [95% CI: 1.34 to 7.23] ml.kg?1.min?1, P = 0.01). Neither conventional LV structural or functional indices, nor LV global longitudinal strain, significantly changed in either group. In contrast, LV twist and twist velocity decreased in the exercise group and increased in the non-exercise group (Difference: ?3.95° [95% CI: ?7.92 to 0.03°], P = 0.05 and ?19.2°.s?1 [95% CI: ?35.9 to ?2.7°.s?1], P = 0.02, respectively).

Conclusion

In MI patients who completed CR exercise training, LV twist and twist velocity decreased, whereas these parameters increased in patients who did not exercise. These preliminary data may indicate reverse LV functional remodelling and improved functional reserve. The assessment of LV twist may serve as an indicator of the therapeutic benefit of CR exercise training and should be investigated in larger trials.  相似文献   
97.
98.

Purpose

The purposes of this study are to characterize magneto-endosymbiont (ME) labeling of mammalian cells and to discern the subcellular fate of these living contrast agents. MEs are novel magnetic resonance imaging (MRI) contrast agents that are being used for cell tracking studies. Understanding the fate of MEs in host cells is valuable for designing in vivo cell tracking experiments.

Procedures

The ME’s surface epitopes, contrast-producing paramagnetic magnetosomal iron, and genome were studied using immunocytochemistry (ICC), Fe and MRI contrast measurements, and quantitative polymerase chain reaction (qPCR), respectively. These assays, coupled with other common assays, enabled validation of ME cell labeling and dissection of ME subcellular processing.

Results

The assays mentioned above provide qualitative and quantitative assessments of cell labeling, the subcellular localization and the fate of MEs. ICC results, with an ME-specific antibody, qualitatively shows homogenous labeling with MEs. The ferrozine assay shows that MEs have an average of 7 fg Fe/ME, ~30 % of which contributes to MRI contrast and ME-labeled MDA-MB-231 (MDA-231) cells generally have 2.4 pg Fe/cell, implying ~350 MEs/cell. Adjusting the concentration of Fe in the ME growth media reduces the concentration of non-MRI contrast-producing Fe. Results from the qPCR assay, which quantifies ME genomes in labeled cells, shows that processing of MEs begins within 24 h in MDA-231 cells. ICC results suggest this intracellular digestion of MEs occurs by the lysosomal degradation pathway. MEs coated with listeriolysin O (LLO) are able to escape the primary phagosome, but subsequently co-localize with LC3, an autophagy-associated molecule, and are processed for digestion. In embryos, where autophagy is transiently suppressed, MEs show an increased capacity for survival and even replication. Finally, transmission electron microscopy (TEM) of ME-labeled MDA-231 cells confirms that the magnetosomes (the MRI contrast-producing particles) remain intact and enable in vivo cell tracking.

Conclusions

MEs are used to label mammalian cells for the purpose of cell tracking in vivo, with MRI. Various assays described herein (ICC, ferrozine, and qPCR) allow qualitative and quantitative assessments of labeling efficiency and provide a detailed understanding of subcellular processing of MEs. In some cell types, MEs are digested, but the MRI-producing particles remain. Coating with LLO allows MEs to escape the primary phagosome, enhances retention slightly, and confirms that MEs are ultimately processed by autophagy. Numerous intracellular bacteria and all endosymbiotically derived organelles have evolved molecular mechanisms to avoid intracellular clearance, and identification of the specific processes involved in ME clearance provides a framework on which to develop MEs with enhanced retention in mammalian cells.
  相似文献   
99.

BACKGROUND

The Gram‐negative bacillus Capnocytophaga canimorsus may cause a severe illness resembling thrombotic thrombocytopenic purpura (TTP). The pathogenesis and optimal therapy of this secondary thrombotic microangiopathy (TMA) remain uncertain.

CASE REPORT

A 63‐year‐old Caucasian man was admitted with suspicion for TTP, but blood cultures grew C. canimorsus. Initial investigations revealed severe thrombocytopenia, a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) activity level of less than 1%, and strongly elevated D‐dimer and lactate dehydrogenase levels. He made a full recovery with antibiotics and plasma infusion for 3 days. Plasmapheresis was not performed. Retrospective determination of serial ADAMTS13 activity levels revealed that ADAMTS13 activity had already increased to 25% at the start of plasma infusion.

CONCLUSION

This case highlights that a C. canimorsus sepsis may cause a secondary TMA with a severe ADAMTS13 deficiency. It also illustrates that the adjunctive role of plasma exchange or plasma infusion is doubtful as ADAMTS13 activity levels increased with antibiotics alone.  相似文献   
100.

Purpose

The aim of the present study was to evaluate the efficacy of an oral formulation of Δ9-tetrahydrocannabinol (ECP002A) in patients with progressive multiple sclerosis (MS).

Methods

This accelerated proof-of-concept study consisted of 2 phases: a crossover challenge (dose-finding) phase and a 4-week, parallel, randomized, placebo-controlled treatment phase. Twenty-four patients with progressive MS and moderate spasticity were enrolled. During the treatment phase, biomarkers for efficacy and secondary pharmacodynamic effects were measured at baseline and after 2 and 4 weeks of treatment. Serum samples were collected to determine pharmacokinetic properties and perform population modeling. Safety and tolerability profiles were assessed based on adverse events and safety measurements.

Findings

Pain was significantly reduced when measured directly after administration of ECP002A in the clinic but not when measured in a daily diary. A similar pattern was observed in subjective muscle spasticity. Other clinical outcomes were not significantly different between active treatment and placebo. Cognitive testing indicated that there was no decline in cognition after 2 or 4 weeks of treatment attributable to ECP002A compared with placebo.ImplicationsThis study specifically underlines the added value of thorough investigation of pharmacokinetic and pharmacodynamic associations in the target population. Despite the complex interplay of psychoactive effects and analgesia, the current oral formulation of Δ9-tetrahydrocannabinol may play a role in the treatment of spasticity and pain associated with MS because it was well tolerated and had a stable pharmacokinetic profile.  相似文献   
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