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51.
Fluorescent proteins are excited by light that is polarized parallel to the dipole axis of the chromophore. In two-photon microscopy, polarized light is used for excitation. Here we reveal surprisingly strong polarization sensitivity in a class of genetically encoded, GPCR-based neurotransmitter sensors. In tubular structures such as dendrites, this effect led to a complete loss of membrane signal in dendrites running parallel to the polarization direction of the excitation beam. To reduce the sensitivity to dendritic orientation, we designed an optical device that generates interleaved pulse trains of orthogonal polarization. The passive device, which we inserted in the beam path of an existing two-photon microscope, removed the strong direction bias from fluorescence and second-harmonic (SHG) images. We conclude that for optical measurements of transmitter concentration with GPCR-based sensors, orthogonally polarized excitation is essential.  相似文献   
52.

Purpose

To evaluate the predictive and prognostic role as well as the clinical impact on decision-making of serum cholinesterase (ChoE) levels in patients treated with radical prostatectomy for clinically nonmetastatic prostate cancer.

Materials and methods

We conducted a retrospective analysis of our multi institutional database. Preoperative ChoE was evaluated as continuous and dichotomized variable using a visual assessment of the functional form of the association of ChoE with biochemical recurrence (BCR)-free survival. We assessed its association with perioperative clinicopathologic characteristics and outcomes. Multivariable models established its independent prognostic value for BCR. Cox proportional hazard coefficients were used to build nomograms for the prediction of early and late BCR. Decision curve analysis was used to assess the clinical impact on decision making of preoperative ChoE.

Results

In all, 6,041 patients were available for the analysis. Decreased ChoE was associated with higher biopsy Gleason score, preoperative PSA levels, pathologic Gleason score, pathological stage, lymph node metastasis, positive surgical margin, and lymphovascular invasion at radical prostatectomy (all P < 0.01). Preoperative ChoE ≤ 6.52 U/ml was associated with higher probability of BCR (HR 1.72, 95% CI 1.48–1.99, P < 0.001). Preoperative and postoperative multivariable models that adjusted for the effects of established clinicopathologic features confirmed its independent association with BCR. In decision curve analysis inclusion of preoperative ChoE did not improve the net benefit of preoperative and postoperative models for the prediction of BCR.

Conclusions

Despite independent association with clinicopathologic features and BCR, preoperative serum ChoE has no impact on clinical decision making. Future studies should investigate the possible relationship between ChoE activity and neoplastic cell transformation with a rational for targeting.  相似文献   
53.
54.

Purpose

To evaluate the effect of preoperative anemia (PA) on oncological outcomes in a multicenter cohort of patients with non–muscle-invasive bladder cancer (NMIBC) treated with transurethral resection of the bladder (TURB) and adjuvant intravesical therapies. We hypothesize that PA represents a marker of disease aggressiveness and could be used to improve the discrimination of prognostic tools for the prediction of disease recurrence and progression.

Methods

This multicenter retrospective study included 1,117 patients from 4 different centers. The presence of PA was assessed according to the World Health Organization classification as a preoperative hemoglobin level of≤13 g/dl in men and≤12 g/dl in women. PA evaluation was done at each institution, generally 1 to 3 days before surgery. Multivariable Cox regression models were performed to evaluate the prognostic effect of PA on survival outcomes.

Results

Overall, 381 (34%) patients with NMIBC treated with TURB, had PA. Median follow-up for patients alive at last follow-up was 62.7 months (interquartile range: 25–110.7). On multivariable Cox regression analyses that accounted for the effect of standard clinicopathologic prognosticators, PA was independently associated with recurrence-free survival (P = 0.045) and progression-free survival (P = 0.01). Adding PA to a model for the prediction of disease recurrence and progression improved the discrimination of the prognostic models marginally from 69.8% to 70.3% and from 71.6% to 73.1%, respectively.

Conclusions

PA was found in more than one-third of patients with NMIBC treated with TURB. PA was associated with poor oncological outcomes and was an independent predictor of intravesical disease recurrence and progression. However, the additional prognostic information provided by PA remains limited.  相似文献   
55.
Significant efforts have been directed to understanding the factors that influence the lineage commitment of stem cells. This paper demonstrates that cell shape, independent of soluble factors, has a strong influence on the differentiation of human mesenchymal stem cells (MSCs) from bone marrow. When exposed to competing soluble differentiation signals, cells cultured in rectangles with increasing aspect ratio and in shapes with pentagonal symmetry but with different subcellular curvature—and with each occupying the same area—display different adipogenesis and osteogenesis profiles. The results reveal that geometric features that increase actomyosin contractility promote osteogenesis and are consistent with in vivo characteristics of the microenvironment of the differentiated cells. Cytoskeletal-disrupting pharmacological agents modulate shape-based trends in lineage commitment verifying the critical role of focal adhesion and myosin-generated contractility during differentiation. Microarray analysis and pathway inhibition studies suggest that contractile cells promote osteogenesis by enhancing c-Jun N-terminal kinase (JNK) and extracellular related kinase (ERK1/2) activation in conjunction with elevated wingless-type (Wnt) signaling. Taken together, this work points to the role that geometric shape cues can play in orchestrating the mechanochemical signals and paracrine/autocrine factors that can direct MSCs to appropriate fates.  相似文献   
56.
Background and Aim:  Liver histology still represents the gold standard for the assessment of liver inflammation, necrosis, and fibrosis. The least cumbersome way of obtaining liver tissue is percutaneous liver biopsy. The aim of this retrospective study was to compare the complications following liver biopsy in in- and outpatients and to evaluate for which patients the benefit from liver biopsy is highest.
Methods:  All patients undergoing percutaneous liver biopsy at a teaching hospital between January 1990 and April 2005 were evaluated for indications, complications and impact of histology.
Results:  Liver biopsy was performed in 287 inpatients and 428 outpatients with a success rate of 99.4%. The total complication rate was 6.3% in inpatients and 11% in outpatients. Only two major complications, but no deaths occurred. Pain was the main complication, especially in young patients with chronic viral hepatitis. Despite normal alanine aminotransferase (ALT) levels advanced liver fibrosis was found in 9.3%, 2.6%, and 5.4% of all patients with HBV-, HCV infection, and non viral liver diseases, respectively. In 3% of all patients evaluated a previously unrecognized second liver disease was found. In 21.4% of the patients alkaline phosphatase (AP) levels were elevated, and in more than 90% of these patients liver biopsy led to the final diagnosis.
Conclusion:  Liver biopsy is safe in in- and outpatients. Biopsy is particularly helpful in patients suspected of having liver disease in spite of normal ALT levels or in patients exhibiting unexplained elevated AP levels.  相似文献   
57.
58.
Although the role of creatine in muscle metabolism is well understood, there is still uncertainty as to its effects at supplemented levels. With this in mind, this study was designed to investigate the direct effects of commercially available creatine on the isolated rat heart, retrogradely perfused and infused with varying concentrations of creatine (1.25, 2.5, 5 and 10 mM) to determine its effects on heart rate, coronary flow and ventricular pressure. Furthermore, tissue from these hearts was used to investigate the cardiotoxic potential of supplemented levels of creatine. Results indicate that creatine directly improves the functioning of the heart under normal conditions with respect to heart rate and ventricular pressure, but may be detrimental to the functioning of energy-deprived hearts. It also showed no cardiotoxic properties since it increased the baseline levels of adenosine triphosphate (ATP) and decreased the levels of isocitrate dehydrogenase (lCD), indicating a decrease in cellular death compared with non-supplemented control hearts.  相似文献   
59.
In the context of a larger study on malaria related knowledge, attitudes, practices and beliefs in western Uganda 813 women aged 15-49 years were shown a sample of a pre-packed, unit-dosed malaria treatment for children, its use was explained and attitudes of the women were investigated. Of all women, 90.5% (86% urban, 92% rural) said they would prefer the pre-packed over the conventional type of treatment and 93.9% of these were willing to pay between 0.17 (rural) and 0.29 (urban) US dollars more for this treatment. Two-thirds (67.8%) thought that they would not have to ask their spouses before making a decision on the kind of treatment and 59.5% said they would rather stock the treatment at home than buy it when a child gets sick. The most mentioned reason for preferring pre-packs was their safety and cleanliness, while ease of application, dosing and compliance were secondary. We conclude that pre-packed, unit-dosed malaria treatment is accepted by the caretakers of children in the area studied and that they readily understand and accept its concept. This indicates a high potential for this approach to improve the home management of malaria fevers and reduce malaria-related morbidity and mortality if adequate coverage can be achieved and if the intervention is embedded into an appropriate programme of behavioural change communication and provider training.  相似文献   
60.
Between April 1996 and December 1999, 76 tibial shaft fractures were treated at the Department of Trauma Surgery of the Justus-Liebig-University in Giessen, Germany and the Department of Orthopedic Surgery of the University of Louisville, USA with a newly developed, unreamed, solid, small diameter tibial nail interlocked "biorigidly" with screws in grooves of the nail. 69 Patients were reviewed with a minimal follow-up period of 16 months. In 65 patients, the fractures united without exchange nailing, although four of these fractures showed a delay of healing. In further four cases, non-union occurred, one of which was associated with the only break of a nail located at a distal interlocking groove of the nail. In one patient, a late medullary infection so far has not recurred following treatment. In 358 implanted interlocking screws, no implant failure was observed. First clinical experience suggests that, especially due to the low rate of material fatigue, the biorigid nail is an alternative to other implants for unreamed intramedullary nailing of the tibia.  相似文献   
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