The mediating role of work-related perceptions in the relationship between empathy and self-perceived clinical performance of residents in China: A multi-center cross-sectional study.

OBJECTIVE: This study aimed to describe the association between empathy and residents' clinical performance and investigate whether work-related perception mediates this relationship. METHODS: A multi-center cross-sectional study was conducted, including 1160 residents from 10 cities in Liaoning Province between March and October 2020. The participants completed various self-reported questionnaires regarding demographic characteristics, work-related perceptions, self-perceived clinical performance, and empathy. The relationships among empathy, work-related perception, and self-perceived clinical performance were examined using a structural equation model (SEM). RESULTS: Of the 1160 residents, 961 (82.8 %) completed the questionnaires. The SEM path analysis showed that the direct effect of empathy on self-perceived clinical performance was significant and positive (ß = 0.34, P < 0.001). There existed significant effects of empathy on work-related perception (ß = 0.26, P < 0.001) and work-related perception on performance (ß = 0.31, P < 0.001). The path coefficients of empathy concerning self-perceived clinical performance decreased significantly (ß = 0.26, P < 0.001) when work-related perception was modeled as a mediator. The bias-corrected and accelerated bootstrap test revealed that work-related perception significantly mediated the relationship between empathy and self-perceived clinical performance (a*b = 0.08, BCa 95 % CI: 0.05-0.13). However, the correlation between the sub-scales of empathy and the items of self-perceived clinical performance was not substantial, even if most of them were statistically significant. The final SEM produced a good fit to the sample data, with CMIN/DF = 2.07 (P < 0.001), CFI = 0.99, GFI = 0.99, AGFI = 0.98, TLI = 0.98, NFI = 0.97, RMSEA (90 % CI) = 0.033 (0.017, 0.049), and SRMR = 0.024. CONCLUSION: Empathy might significantly affect self-perceived clinical performance both directly and indirectly through the mediating role of work-related perception. PRACTICE IMPLICATIONS: Efforts to improve clinical performance among residents might benefit from interventions for cultivating empathy and practices for improving work-related perceptions of residents.

Wide-field endoscope accessory for multiplexed fluorescence imaging.

A wide-field endoscope that is sensitive to fluorescence can be used as an adjunct to conventional white light endoscopy by detecting multiple molecular targets concurrently. We aim to demonstrate a flexible fiber-coupled accessory that can pass forward through the instrument channel of standard medical endoscopes for clinical use to collect fluorescence images. A miniature scan mirror with reflector dimensions of 1.30 × 0.45  mm2 was designed, fabricated, and placed distal to collimated excitation beams at λex = 488, 660, and 785 nm. The mirror was driven at resonance for wide angular deflections in the X and Y-axes. A large image field-of-view (FOV) was generated in real time. The optomechanical components were packaged in a rigid distal tip with dimensions of 2.6 mm diameter and 12 mm length. The scan mirror was driven at 27.6 and 9.04 kHz in the fast (X) and slow (Y) axes, respectively, using a square wave with 50% duty cycle at 60 Vpp to collect fluorescence images at 10 frames per sec. Maximum total divergence angles of ± 27.4° and ± 22.8° were generated to achieve a FOV of 10.4 and 8.4 mm, respectively, at a working distance of 10 mm. Multiplexed fluorescence images were collected in vivo from the rectum of live mice using 3 fluorescently-labeled peptides that bind to unique cell surface targets. The fluorescence images collected were separated into 3 channels. Target-to-background ratios of 2.6, 3.1, and 3.9 were measured. This instrument demonstrates potential for broad clinical use to detect heterogeneous diseases in hollow organs.

Design, synthesis and SAR of novel 7-azaindole derivatives as potential Erk5 kinase inhibitor with anticancer activity.

The extracellular signal-regulated kinase 5 (Erk5) signaling plays a crucial role in cancer, and regulating its activity may have potential in cancer chemotherapy. In this study, a series of novel 7-azaindole derivatives (4a-5o) were designed and synthesized. Their antitumor activities on human lung cancer A549 cells was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, 4',6-diamidino-2-phenylindole (DAPI) staining and colony formation assay. Among them, compounds 4a, 4 h, 5d and 5j exhibited good anti-proliferative activity with the IC50 values of 6.23 µg/mL, 8.52 µg/mL, 7.33 µg/mL and 4.56 µg/mL, respectively, equivalent to Erk5 positive control XMD8-92 (IC50 = 5.36 µg/mL). The results of structure-activity relationships (SAR) showed that double bond on the piperidine ring and N atoms at the N7 position of 7-azaindole was essential for their antiproliferative activity. Furthermore, compounds 4a and 5j exhibited good inhibition on Erk5 kinase through Western blot analysis and possible action site of compounds with Erk5 kinase was elucidated by molecular docking.

Efficient production of cordycepin by engineered Yarrowia lipolytica from agro-industrial residues.

Cordycepin, a nucleoside compound with a variety of biological activities, has been extensively applied in the nutraceutical and pharmaceutical industries. The advancement of microbial cell factories using agro-industrial residues provides a sustainable pathway for cordycepin biosynthesis. Herein, the cordycepin production was enhanced by the modification of glycolysis and pentose phosphate pathway in engineered Yarrowia lipolytica. Then, cordycepin production based on economical and renewable substrates (sugarcane molasses, waste spent yeast, and diammonium hydrogen phosphate) was analyzed. Furthermore, the effects of C/N molar ratio and initial pH on cordycepin production were evaluated. Results indicated that the maximum cordycepin productivity of 656.27 mg/L/d (72 h) and cordycepin titer was 2286.04 mg/L (120 h) by engineered Y. lipolytica in the optimized medium, respectively. The cordycepin productivity in the optimized medium was increased by 28.81% compared with the original medium. This research establishes a promising way for efficient cordycepin production from agro-industrial residues.

Increased Cordycepin Production in Yarrowia lipolytica Using Combinatorial Metabolic Engineering Strategies.

As the first nucleoside antibiotic discovered in fungi, cordycepin, with its various biological activities, has wide applications. At present, cordycepin is mainly obtained from the natural fruiting bodies of Cordyceps militaris. However, due to long production periods, low yields, and low extraction efficiency, harvesting cordycepin from natural C. militaris is not ideal, making it difficult to meet market demands. In this study, an engineered Yarrowia lipolytica YlCor-18 strain, constructed by combining metabolic engineering strategies, achieved efficient de novo cordycepin production from glucose. First, the cordycepin biosynthetic pathway derived from C. militaris was introduced into Y. lipolytica. Furthermore, metabolic engineering strategies including promoter, protein, adenosine triphosphate, and precursor engineering were combined to enhance the synthetic ability of engineered strains of cordycepin. Fermentation conditions were also optimized, after which, the production titer and yields of cordycepin in the engineered strain YlCor-18 under fed-batch fermentation were improved to 4362.54 mg/L and 213.85 mg/g, respectively, after 168 h. This study demonstrates the potential of Y. lipolytica as a cell factory for cordycepin synthesis, which will serve as the model for the green biomanufacturing of other nucleoside antibiotics using artificial cell factories.

Confocal laser endomicroscope with distal MEMS scanner for real-time histopathology.

Confocal laser endomicroscopy is an emerging methodology to perform real time optical biopsy. Fluorescence images with histology-like quality can be collected instantaneously from the epithelium of hollow organs. Currently, scanning is performed at the proximal end of probe-based instruments used routinely in the clinic, and flexibility to control the focus is limited. We demonstrate use of a parametric resonance scanner packaged in the distal end of the endomicroscope to perform high speed lateral deflections. An aperture was etched in the center of the reflector to fold the optical path. This design reduced the dimensions of the instrument to 2.4 mm diameter and 10 mm length, allowing for forward passage through the working channel of a standard medical endoscope. A compact lens assembly provides lateral and axial resolution of 1.1 and 13.6 µm, respectively. A working distance of 0 µm and field-of-view of 250 µm × 250 µm was achieved at frame rates up to 20 Hz. Excitation at 488 nm was delivered to excite fluorescein, an FDA-approved dye, to generate high tissue contrast. The endomicroscope was reprocessed using a clinically-approved sterilization method for 18 cycles without failure. Fluorescence images were collected during routine colonoscopy from normal colonic mucosa, tubular adenomas, hyperplastic polyps, ulcerative colitis, and Crohn's colitis. Individual cells, including colonocytes, goblet cells, and inflammatory cells, could be identified. Mucosal features, such as crypt structures, crypt lumens, and lamina propria, could be distinguished. This instrument has potential to be used as an accessory during routine medical endoscopy.

HIV-Specific Reported Outcome Measures: Systematic Review of Psychometric Properties.

BACKGROUND: The management of people living with HIV and AIDS is multidimensional and complex. Using patient-reported outcome measures (PROMs) has been increasingly recognized to be the key factor for providing patient-centered health care to meet the lifelong needs of people living with HIV and AIDS from diagnosis to death. However, there is currently no consensus on a PROM recommended for health care providers and researchers to assess health outcomes in people living with HIV and AIDS. OBJECTIVE: The purpose of this systematic review was to summarize and categorize the available validated HIV-specific PROMs in adults living with HIV and AIDS and to assess these PROMs using the Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) methodology. METHODS: This systematic review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A literature search of 3 recommended databases (PubMed, Embase, and PsychINFO) was conducted on January 15, 2021. Studies were included if they assessed any psychometric property of HIV-specific PROMs in adults living with HIV and AIDS and met the eligibility criteria. The PROMs were assessed for 9 psychometric properties, evaluated in each included study following the COSMIN methodology by assessing the following: the methodological quality assessed using the COSMIN risk of bias checklist; overall rating of results; level of evidence assessed using the modified Grading of Recommendations, Assessment, Development, and Evaluation approach; and level of recommendation. RESULTS: A total of 88 PROMs classified into 8 categories, assessing the psychometric properties of PROMs for adults living with HIV and AIDS, were identified in 152 studies including 79,213 people living with HIV and AIDS. The psychometric properties of most included PROMs were rated with insufficient evidence. The PROMs that received class A recommendation were the Poz Quality of Life, HIV Symptom Index or Symptoms Distress Module of the Adult AIDS Clinical Trial Group, and People Living with HIV Resilience Scale. In addition, because of a lack of evidence, recommendations regarding use could not be made for most of the remaining assessed PROMs (received class B recommendation). CONCLUSIONS: This systematic review recommends 3 PROMs to assess health outcomes in adults living with HIV and AIDS. However, all these PROMs have some shortcomings. In addition, most of the included PROMs do not have sufficient evidence for assessing their psychometric properties and require a more comprehensive validation of the psychometric properties in the future to provide more scientific evidence. Thus, our findings may provide a reference for the selection of high-quality HIV-specific PROMs by health care providers and researchers for clinical practice and research.

High-level de novo biosynthesis of cordycepin by systems metabolic engineering in Yarrowia lipolytica.

Cordycepin is a nucleoside antibiotic with various biological activities, which has wide applications in the area of cosmetic and medicine industries. However, the current production of cordycepin is costly and time-consuming. To construct the promising cell factory for high-level cordycepin production, firstly, the design and construction of cordycepin biosynthetic pathway were performed in Yarrowia lipolytica. Secondly, the adaptivity between cordycepin biosynthetic pathway and Y. lipolytica was enhanced by enzyme fusion and integration site engineering. Then, the production of cordycepin was improved by the enhancement of adenosine supply. Furthermore, through modular engineering, the production of cordycepin was achieved at 3588.59 mg/L from glucose. Finally, 3249.58 mg/L cordycepin with a yield of 76.46 mg/g total sugar was produced by the engineered strain from the mixtures of glucose and molasses. This research is the first report on the de novo high-level production of cordycepin in the engineered Y. lipolytica.

Image processing metrics for phase identification of a multiaxis MEMS scanner used in single pixel imaging.

This paper applies image processing metrics to tracking of perturbations in mechanical phase delay in a multi-axis microelectromechanical system (MEMS) scanner. The compact mirror is designed to scan a laser beam in a Lissajous pattern during the collection of endoscopic confocal fluorescence images, but environmental perturbations to the mirror dynamics can lead to image registration errors and blurry images. A binarized, threshold-based blur metric and variance-based sharpness metric are introduced for detecting scanner phase delay. Accuracy of local optima of the metric for identification of phase delay is examined, and relative advantages for processing accuracy and computational complexity are assessed. Image reconstruction is demonstrated using both generic images and sample tissue images, with significant improvement in image quality for tissue imaging. Implications of non-ideal Lissajous scan effects on phase detection and image reconstruction are discussed.

Valproate Reverses Mania-Like Behavior of Clock delta19 Mouse and Alters Monoamine Neurotransmitters Metabolism in the Hippocampus.

BACKGROUND: Mice with a deletion at exon 19 of the circadian locomotor output cycles Kaput gene (Clock delta19) exhibit mania-like behavior and have been one of the most common animal models for bipolar disorder (BD). The predictive validity of the Clock delta19 was investigated via studies using lithium previously. Determination of effects of other mood stabilizers on Clock delta19 mouse would be helpful for better understanding of the mechanism underlined. METHODS: Wildtype (WT) and Clock delta19 mice were treated with saline (n = 10 for WT and n=10 for Clock delta19) or valproate (VPA) (n = 10 for WT and n=10 for Clock delta19) for 10 days. The hyperactivity, anxiety-like behaviors and depression-like behaviors were tested. The concentration of monoamine neurotransmitters and their metabolites in the hippocampus of saline or VPA treated WT and Clock delta19 mouse (n = 8 for each) were also determined. RESULTS: VPA can reverse hyperactivity, lower level of anxiety-like and depression-like behaviors of the Clock delta19 mouse. Clock delta19 mouse exhibited lower levels of serotonin (5-HT) and dopamine (DA) in right hippocampus compared to WT mouse. Chronic VPA treatment did not affect the levels of 5-HT and DA, but can reduce the level of levodopa (L-DOPA) in the right hippocampus of Clock delta19 mouse. CONCLUSION: Our results indicated that chronic VPA treatment can reverse the mania-like behaviors of the Clock delta19 mouse and further consolidate the validity of the Clock delta19 mouse as a model of BD. Monoamine neurotransmitters and their metabolites in the hippocampus are partly regulated by mutation of the Clock gene or VPA treatment.

[Advances in the biosynthesis of pentostatin].

Pentostatin is a nucleoside antibiotics with a strong inhibitory effect on adenosine deaminase, and is widely used in the clinical treatment of malignant tumors. However, the high cost hampers its application. In the past 10 years, the biosynthesis of pentostatin were focused on strain breeding, optimization of medium composition and fermentation process. To date, there are no reviews summarizing the elucidated biosynthetic mechanism of pentostatin. This review starts by introducing the various chemical route for production of pentostatin, followed by summarizing the mechanisms of pentostatin biosynthesis in different microorganisms. Finally, challenges for biosynthesis of pentostatin were discussed, and strategies for regulating and improving the microbial synthesis of pentostatin were proposed.

[Correlation between altered levels of neurotransmitters in the frontal lobe and hippocampus and behavioral abnormalities in a Clockdelta19 mutant mice modeling bipolar manic disorder].

OBJECTIVE: To explore the correlation between altered levels of neurotransmitters in the frontal lobe and hippocampus and behavioral abnormalities in a Clockdelta19 variant mice modeling bipolar disorder manic disorder. METHODS: Open field test and Elevated plus-maze test were carried out on the Clockdelta19 mutant and wild-type control groups. The frontal lobe and hippocampus of Clockdelta19 mutant mice and controls were dissected, and neurotransmitters in tissue extracts were analyzed by high-performance liquid chromatography and mass spectrometry. The concentration of neurotransmitters and behavioral indicators were assessed by t test and Pearson correlation analysis using SPSS 22.0. RESULTS: The Clockdelta19 mutant mice showed a significant increase in activity, albeit with no difference in the level of anxiety from the wild-type controls, which suggested that the Clockdelta19 mutant mice can be used as a model for manic attack of bipolar disorder. Altered neurotransmitter levels were detected in the frontal and hippocampal regions, including elevated histamine in the left hippocampus, reduced histamine in the right hippocampus, reduced gamma-aminobutyric acid (GABA) in bilateral hippocampus, elevated dihydroxyphenylalanine (DOPA) in the left frontal lobe and reduced DOPA in the right hippocampus, and decreased glutamine in bilateral frontal lobes. The reduced glutamine in the left frontal lobe and GABA in the right hippocampus correlated with the increased activity of Clockdelta19 mutant mice. CONCLUSION: Clockdelta19 mutant mice showed abnormal behavior with increased activity. Reduced glutamine in the left frontal lobe and GABA in the right hippocampus were correlated with increased activity.

Ultra-Compact Microsystems-Based Confocal Endomicroscope.

Point-of-care medical diagnosis demands immediate feedback on tissue pathology. Confocal endomicroscopy can provide real-time in vivo images with histology-like features. The working channel in medical endoscopes are becoming smaller in dimension. Microsystems methods can produce tiny mechanical scanners. We demonstrate a flexible fiber instrument for in vivo imaging as an endoscope accessory. The optical path is folded on-axis to reduce length while allowing the beam to expand and achieve a numerical aperture of 0.41. A high-speed parametric resonance mirror produces large deflection angles > 13°, and is mounted on a 2 mm diameter chip designed with clamp structures for reduced space. A compact lens assembly provides diffraction-limited lateral and axial resolution of 1.5 and [Formula: see text], respectively. A working distance of [Formula: see text] and field-of-view of [Formula: see text] m are achieved. Miniature apparatus is fabricated to assemble and align the scanhead components. The optics and scanner are packaged in a distal tip with 2.4 mm diameter and 10 mm rigid length. These dimensions allow the endomicroscope to pass forward easily through the 2.8 mm diameter working channel in medical endoscopes commonly used in clinical practice. Fluorescence images are collected in vivo at 10 frames per second in the colon of genetically-engineered mice that spontaneously develop adenomas. A FITC-labeled peptide heterodimer is administered intravenously to provide specific contrast. Sub-cellular structures are visualized to distinguish pre-malignant from normal mucosa. These results demonstrate use of microsystems methods to produce an ultra-compact instrument with sufficiently small dimensions for broad use.

Integrated Imaging Methodology Detects Claudin-1 Expression in Premalignant Nonpolypoid and Polypoid Colonic Epithelium in Mice.

OBJECTIVES: Conventional colonoscopy with white light illumination detects colonic adenomas based on structural changes alone and is limited by a high miss rate. We aim to demonstrate an integrated imaging strategy that combines wide-field endoscopy and confocal endomicroscopy in real time to visualize molecular expression patterns in vivo to detect premalignant colonic mucosa. METHODS: A peptide specific for claudin-1 is labeled with Cy5.5 and administrated intravenously in genetically engineered mice that develop adenomas spontaneously in the distal colon. Wide-field endoscopy is used to identify the presence of nonpolypoid and polypoid adenomas. Anatomic landmarks are used to guide placement of a confocal endomicroscope with side-view optics to visualize claudin-1 expression patterns with subcellular resolution. RESULTS: Wide-field fluorescence images show peak uptake in colon adenoma at ∼1 hour after systemic peptide administration, and lesion margins are clearly defined. Further examination of the lesion using a confocal endomicroscope shows dysplastic crypts with large size, elongated shape, distorted architecture, and variable dimension compared with normal. The mean fluorescence intensity is significantly higher for dysplasia than normal. Increased claudin-1 expression in dysplasia vs normal is confirmed ex vivo, and the binding pattern is consistent with the in vivo imaging results. DISCUSSION: Wide-field endoscopy can visualize molecular expression of claudin-1 in vivo to localize premalignant colonic mucosa, and confocal endomicroscopy can identify subcellular feature to distinguish dysplasia from normal.

Motion Estimation for a Compact Electrostatic Microscanner via Shared Driving and Sensing Electrodes in Endomicroscopy.

We present a method to estimate high frequency rotary motion of a highly compact electrostatic micro-scanner using the same electrodes for both actuation and sensing. The accuracy of estimated rotary motion is critical for reducing blur and distortion in image reconstruction applications with the micro-scanner given its changing dynamics due to perturbations such as temperature. To overcome the limitation that no dedicated sensing electrodes are available in the proposed applications due to size constraints, the method adopts electromechanical amplitude modulation (EAM) to separate motion signal from parasitic capacitance feedthrough, and a novel non-linear measurement model is derived to characterize the relationship between large out-of-plane angular motion and circuit output. To estimate motion, an extended Kalman filter (EKF) and an unscented Kalman filter (UKF) are implemented, incorporating a process model based on the micro-scanner's parametric resonant dynamics and the measurement model. Experimental results show that compared to estimation without using the measurement model, our method is able to improve the rotary motion estimation accuracy of the micro-scanner significantly, with a reduction of root-mean-square error (RMSE) in phase shift of 86.1%, and a reduction of RMSE in angular position error of 78.5 %.

Complete Genome Sequence of Bacteriocin-Producing Enterococcus faecium HY07.

Here, we report the draft genome sequence of the bacteriocin-producing Enterococcus faecium strain HY07, isolated from traditional Chinese fermented sausages. The genome comprises 2,585,631 bp with 2,624 coding sequences, as assigned by NCBI, which may provide fundamental molecular information on elucidating the adaption mechanism of Enterococcus faecium to the meat environment.

Multiplexed Targeting of Barrett's Neoplasia with a Heterobivalent Ligand: Imaging Study on Mouse Xenograft in Vivo and Human Specimens ex Vivo.

Esophageal adenocarcinoma (EAC) is a molecularly heterogeneous disease that is rising rapidly in incidence and has poor prognosis. We developed a heterobivalent peptide to target detection of early Barrett's neoplasia by combining monomer heptapeptides specific for either EGFR or ErbB2 in a heterodimer configuration. The structure of a triethylene glycol linker was optimized to maximize binding interactions to the surface receptors on cells. The Cy5.5-labeled heterodimer QRH*-KSP*-E3-Cy5.5 demonstrated specific binding to each target and showed 3-fold greater fluorescence intensity and 2-fold higher affinity compared with those of either monomer alone. Peak uptake in xenograft tumors was observed at 2 h postinjection with systemic clearance by ∼24 h in vivo. Furthermore, ligand binding was evaluated on human esophageal specimens ex vivo, and 88% sensitivity and 87% specificity were found for the detection of either high-grade dysplasia (HGD) or EAC. This peptide heterodimer shows promise for targeted detection of early Barrett's neoplasia in clinical study.

In vivo near-infrared imaging of ErbB2 expressing breast tumors with dual-axes confocal endomicroscopy using a targeted peptide.

ErbB2 expression in early breast cancer can predict tumor aggressiveness and clinical outcomes in large patient populations. Accurate assessment with physical biopsy and conventional pathology can be limited by tumor heterogeneity. We aim to demonstrate real-time optical sectioning using a near-infrared labeled ErbB2 peptide that generates tumor-specific contrast in human xenograft breast tumors in vivo. We used IRDye800CW as the fluorophore, validated performance characteristics for specific peptide binding to cells in vitro, and investigated peak peptide uptake in tumors using photoacoustic tomography. We performed real-time optical imaging using a handheld dual-axes confocal fluorescence endomicroscope that collects light off-axis to reduce tissue scattering for greater imaging depths. Optical sections in either the vertical or horizontal plane were collected with sub-cellular resolution. Also, we found significantly greater peptide binding to pre-clinical xenograft breast cancer in vivo and to human specimens of invasive ductal carcinoma that express ErbB2 ex vivo. We used a scrambled peptide for control. Peptide biodistribution showed high tumor uptake by comparison with other organs to support safety. This novel integrated imaging strategy is promising for visualizing ErbB2 expression in breast tumors and serve as an adjunct during surgery to improve diagnostic accuracy, identify tumor margins, and stage early cancers.

Visualizing Epithelial Expression in Vertical and Horizontal Planes With Dual Axes Confocal Endomicroscope Using Compact Distal Scanner.

The epithelium is a thin layer of tissue that lines hollow organs, such as colon. Visualizing in vertical cross sections with sub-cellular resolution is essential to understanding early disease mechanisms that progress naturally in the plane perpendicular to the tissue surface. The dual axes confocal architecture collects optical sections in tissue by directing light at an angle incident to the surface using separate illumination and collection beams to reduce effects of scattering, enhance dynamic range, and increase imaging depth. This configuration allows for images to be collected in the vertical as well as horizontal planes. We designed a fast, compact monolithic scanner based on the principle of parametric resonance. The mirrors were fabricated using microelectromechanical systems (MEMS) technology and were coated with aluminum to maximize near-infrared reflectivity. We achieved large axial displacements [Formula: see text] and wide lateral deflections >20°. The MEMS chip has a 3.2×2.9 mm2 form factor that allows for efficient packaging in the distal end of an endomicroscope. Imaging can be performed in either the vertical or horizontal planes with [Formula: see text] depth or 1 ×1 mm2 area, respectively, at 5 frames/s. We systemically administered a Cy5.5-labeled peptide that is specific for EGFR, and collected near-infrared fluorescence images ex vivo from pre-malignant mouse colonic epithelium to reveal the spatial distribution of this molecular target. Here, we demonstrate a novel scanning mechanism in a dual axes confocal endomicroscope that collects optical sections of near-infrared fluorescence in either vertical or horizontal planes to visualize molecular expression in the epithelium.

Axial beam scanning in multiphoton microscopy with MEMS-based actuator.

We demonstrate a remotely located microelectromechanical systems (MEMS) actuator that can translate >400 µm to perform axial beam scanning in a multiphoton microscope. We use a 2-dimensional MEMS mirror for lateral scanning, and collected multiphoton excited fluorescence images in either the horizontal or vertical plane with a field-of-view of either 270 × 270 or 270 × 200 µm2, respectively, at 5 frames per second. Axial resolution varied from 4.5 to 7 µm over the scan range. The compact size of the actuator and scanner allows for use in an endomicroscope to collect images in the vertical plane with >200 µm depth.