Method to quantify accuracy of position feedback signals of a three-dimensional two-photon laser-scanning microscope

Two-photon laser-scanning microscopy enables to record neuronal network activity in three-dimensional space while maintaining single-cellular resolution. One of the proposed approaches combines galvanometric x-y scanning with piezo-driven objective movements and employs hardware feedback signals for position monitoring. However, readily applicable methods to quantify the accuracy of those feedback signals are currently lacking. Here we provide techniques based on contact-free laser reflection and laser triangulation for the quantification of positioning accuracy of each spatial axis. We found that the lateral feedback signals are sufficiently accurate (defined as <2.5 µm) for a wide range of scan trajectories and frequencies. We further show that axial positioning accuracy does not only depend on objective acceleration and mass but also its geometry. We conclude that the introduced methods allow a reliable quantification of position feedback signals in a cost-efficient, easy-to-install manner and should be applicable for a wide range of two-photon laser scanning microscopes.OCIS codes: (180.6900) Three-dimensional microscopy, (180.4315) Nonlinear microscopy, (170.0180) Microscopy, (170.2520) Fluorescence microscopy, (180.2520) Fluorescence microscopy     

kappa gene diversity among the clonal progeny of pre-B lymphocytes.

Some clonal pre-B cell lines, when transformed by Abelson murine leukemia virus, are able to rearrange and express kappa light chain genes. We have analyzed the light chains expressed in sets of early B-cell subclones derived from two pre-B cell clones. Each subclone makes an indistinguishable mu heavy chain, while the kappa gene rearrangements and proteins synthesized were distinct. All members of one set of subclones expressed a V kappa 21 kappa light chain. Only one of the members of the other two sets of subclones expressed V kappa 21. Thus, a single pre-B-cell clone can select a kappa variable region from more than one family. In each subclone of the set that expressed V kappa 21 light chain the same member appears to be used. The differences detected in the expressed proteins can best be explained by primary sequence alterations in the rearranged V kappa 21 segment. These sequence alterations have resulted in a restriction site polymorphism in the expressed V kappa 21 gene and charge and size differences in the expressed proteins. These data suggest that diversification of kappa light chains can occur at the pre-B- to early B-cell stage of development.     

Prostate cancer detection upon transrectal ultrasound-guided biopsy in relation to digital rectal examination and prostate-specific antigen level: what to expect in the Chinese population?

We investigated the prostate cancer detection rates upon transrectal ultrasound (TRUS)-guided biopsy in relation to digital rectal examination (DRE) and prostate-specific antigen (PSA), and risk factors of prostate cancer detection in the Chinese population. Data from all consecutive Chinese men who underwent first TRUS-guided prostate biopsy from year 2000 to 2013 was retrieved from our database. The prostate cancer detection rates with reference to DRE finding and PSA level of < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml⁻¹ were investigated. Multivariate logistic regression analyses were performed to investigate for potential risk factors of prostate cancer detection. A total of 2606 Chinese men were included. In patients with normal DRE, the cancer detection rates were 8.6%, 13.4%, 21.8%, 41.7% and 85.2% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml⁻¹ respectively. In patients with abnormal DRE, the cancer detection rates were 12.4%, 30.2%, 52.7%, 80.6% and 96.4% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml⁻¹ respectively. Older age, smaller prostate volume, larger number of biopsy cores, presence of abnormal DRE finding and higher PSA level were associated with increased risk of prostate cancer detection upon multivariate logistic regression analyses (P < 0.001). Chinese men appeared to have lower prostate cancer detection rates when compared to the Western population. Taking the different risk factors into account, an individualized approach to the decision of TRUS-guided biopsy can be adopted.     

Bone marrow transplantation from HLA-identical siblings as treatment for myelodysplasia

Allogeneic hematopoietic stem cell transplantation is the only curative therapy for myelodysplasia (MDS). To identify factors influencing transplantation outcome, we studied 452 recipients of HLA-identical sibling transplants for MDS from 1989 to 1997, reported to the International Bone Marrow Transplant Registry. Patients with treatment-related MDS or unclassified MDS were excluded. Median age was 38 years (range, 2-64 years). Sixty percent had refractory anemia with excess blasts (n = 136) or with excess blasts in transformation (n = 136). Conditioning regimens included total body irradiation in 199 (44%) cases. Marrow was T-cell depleted for 58 (13%) transplants. Cumulative incidences of neutrophil engraftment, grades II-IV acute graft-versus-host disease (GVHD), and chronic GVHD were 91% (95% confidence interval [CI], 88%-93%), 36% (95% CI, 31%-40%), and 39% (95% CI, 33%-44%), respectively. Three-year transplantation-related mortality (TRM), relapse, disease-free survival, and overall survival rates were 37% (95% CI, 32%-42%), 23% (95% CI, 19%-27%), 40% (95% CI, 36%-45%), and 42% (95% CI, 37%-47%), respectively. Multivariate analyses showed that young age and platelet counts higher than 100 x 10(9)/L at transplantation were associated with lower TRM and higher disease-free and overall survival rates. Relapse incidence was higher in patients with high percentages of blasts in the marrow at transplantation or presentation, with high International Prognostic Scoring System scores at diagnosis, and with T-cell-depleted transplants. These findings indicate that transplantation from an HLA-identical sibling offers the possibility of long-term, disease-free survival to patients with MDS. Best candidates are younger patients with a low percentage of blasts and preserved platelet counts.     

It's LiFe! Mobile and Web-Based Monitoring and Feedback Tool Embedded in Primary Care Increases Physical Activity: A Cluster Randomized Controlled Trial

BackgroundPhysical inactivity is a major public health problem. The It’s LiFe! monitoring and feedback tool embedded in the Self-Management Support Program (SSP) is an attempt to stimulate physical activity in people with chronic obstructive pulmonary disease or type 2 diabetes treated in primary care.ObjectiveOur aim was to evaluate whether the SSP combined with the use of the monitoring and feedback tool leads to more physical activity compared to usual care and to evaluate the additional effect of using this tool on top of the SSP.MethodsThis was a three-armed cluster randomised controlled trial. Twenty four family practices were randomly assigned to one of three groups in which participants received the tool + SSP (group 1), the SSP (group 2), or care as usual (group 3). The primary outcome measure was minutes of physical activity per day. The secondary outcomes were general and exercise self-efficacy and quality of life. Outcomes were measured at baseline after the intervention (4-6 months), and 3 months thereafter.ResultsThe group that received the entire intervention (tool + SSP) showed more physical activity directly after the intervention than Group 3 (mean difference 11.73, 95% CI 6.21-17.25; P<.001), and Group 2 (mean difference 7.86, 95% CI 2.18-13.54; P=.003). Three months after the intervention, this effect was still present and significant (compared to Group 3: mean difference 10.59, 95% CI 4.94-16.25; P<.001; compared to Group 2: mean difference 9.41, 95% CI 3.70-15.11; P<.001). There was no significant difference in effect between Groups 2 and 3 on both time points. There was no interaction effect for disease type.ConclusionsThe combination of counseling with the tool proved an effective way to stimulate physical activity. Counseling without the tool was not effective. Future research about the cost-effectiveness and application under more tailored conditions and in other target groups is recommended.

Trial Registration

ClinicalTrials.gov: {"type":"clinical-trial","attrs":{"text":"NCT01867970","term_id":"NCT01867970"}}NCT01867970, https://clinicaltrials.gov/ct2/show/{"type":"clinical-trial","attrs":{"text":"NCT01867970","term_id":"NCT01867970"}}NCT01867970 (archived by WebCite at http://www.webcitation.org/6a2qR5BSr).     

Noninvasive detection of tumor-infiltrating T cells by PET reporter imaging

Adoptive transfer of tumor-reactive T cells can successfully reduce tumor burden; however, in rare cases, lethal on-target/off-tumor effects have been reported. A noninvasive method to track engineered cells with high sensitivity and resolution would allow observation of correct cell homing and/or identification of dangerous off-target locations in preclinical and clinical applications. Human deoxycytidine kinase triple mutant (hdCK3mut) is a nonimmunogenic PET reporter that was previously shown to be an effective tool to monitor whole-body hematopoiesis. Here, we engineered a construct in which hdCK3mut is coexpressed with the anti-melanoma T cell receptor F5, introduced this construct into human CD34 cells or PBMCs, and evaluated this approach in multiple immunotherapy models. Expression of hdCK3mut allowed engrafted cells to be visualized within recipient bone marrow, while accumulation of [¹⁸F]-L-FMAU in hdCK3mut-expressing T cells permitted detection of intratumoral homing. Animals that received T cells coexpressing hdCK3mut and the anti-melanoma T cell receptor had demonstrably higher signals in HLA-matched tumors compared with those in animals that received cells solely expressing hdCK3mut. Engineered T cells caused cytotoxicity in HLA/antigen-matched tumors and induced IFN-γ production and activation. Moreover, hdCK3mut permitted simultaneous monitoring of engraftment and tumor infiltration, without affecting T cell function. Our findings suggest that hdCK3mut reporter imaging can be applied in clinical immunotherapies for whole-body detection of engineered cell locations.     

Theoretical approach towards increasing effectiveness of palatal surgery in obstructive sleep apnea: role for concomitant positional therapy?

Purpose

The aims of this study are to evaluate the effect of palatal surgery (uvulopalatopharyngoplasty (UPPP) or Z-palatoplasty (ZPP)) with or without (+/?) concomitant radiofrequent ablation of the base of the tongue (RFTB) on body position-specific apnea–hypopnea index (AHI) values in patients with obstructive sleep apnea (OSA) and to compare this treatment outcome to the theoretical effect of (addition of) positional therapy (PT).

Methods

Retrospective analysis of pre- and posttreatment polysomnographies in 139 patients who had undergone UPPP/ZPP +/? RFTB was performed. Hypothetical evaluation of the effects of (addition of) ideal PT on AHI in positional OSA (POSA) patients was carried out.

Results

Median AHI significantly decreased from 18.0 to 11.2 (p?<?0.001). Median AHI in all separate positions decreased significantly as well. Sixty-eight patients suffered from POSA and showed a significant decrease in median AHI from 15.5 to 11.5 (p?=?0.002). In the 71 non-positional OSA (NPOSA) patients, the significant AHI decrease was more outspoken, from 23.0 to 11.0 (p?<?0.001). Our hypothetical model to treat POSA patients with an ideal PT (as monotherapy or in addition to surgery) resulted in a significant median AHI decrease from 18.0 to 4.5 (p?<?0.0001).

Conclusions

UPPP/ZPP +/? RFTB significantly reduces AHI and all body position-specific AHI values. This reduction is significantly higher in NPOSA than in POSA patients. When considering UPPP/ZPP +/? RFTB, the effect of body position needs to be taken into account. PT, either as monotherapy or in addition to surgery, theoretically has shown to improve treatment results dramatically in POSA patients. Prospective, controlled trials focusing on the effects of this combination of treatments should further evaluate this hypothetical conclusion.     

Xenophagy in Helicobacter pylori‐ and Epstein–Barr virus‐induced gastric cancer

Helicobacter pylori and Epstein–Barr virus (EBV) account for roughly 80% and 10%, respectively, of gastric carcinomas worldwide. Autophagy is an evolutionarily conserved and intricately regulated cellular process that involves the sequestration of cytoplasmic proteins and organelles into double‐membrane autophagosomes that eventually fuse with lysosomes for degradation of the engulfed content. Emerging evidence indicates that xenophagy, a form of selective autophagy, plays a crucial role in the pathogenesis of H. pylori‐ and EBV‐induced gastric cancer. Xenophagy specifically recognizes intracellular H. pylori and EBV and physically targets these pathogens to the autophagosomal–lysosomal pathway for degradation. In this connection, H. pylori or EBV‐induced dysregulation of autophagy may be causally linked to gastric tumourigenesis and therefore can be exploited as therapeutic targets. This review will discuss how H. pylori and EBV infection activate autophagy and how these pathogens evade recognition and degradation by the autophagic pathway. Elucidating the molecular aspects of H. pylori‐ and EBV‐induced autophagy will help us better understand the pathogenesis of gastric cancer and promote the development of autophagy modulators as antimicrobial agents. Published by John Wiley & Sons, Ltd