Diversity of the free helical rim flap: A case series tailoring the microsurgical technique to esthetically optimize full-thickness nasal defect reconstructions.

INTRODUCTION: The free helical rim (FHR) flap offers like-with-like reconstruction for full-thickness nasal defects. A case series of nasal reconstruction using an FHR flap was presented, detailing surgical steps and refinements, as well as functional and esthetic outcomes. METHODS AND MATERIALS: This is a retrospective cohort study of composite nasal defect reconstruction with FHR flap from August 2018 to March 2020. Descriptive data were analyzed by SPSS software. RESULTS: Six cases were recruited, four were unilateral alar defects, one was hemi-nose, and one was ala plus tip. The average size of the defect was 2.5 × 2.8 cm2. Three FHR flaps were designed with retrograde pedicles and three with anterograde pedicles. The facial artery and veins were the recipient vessels in all cases. Vascular grafts were used in all six cases. Descending branch of the lateral circumflex femoral (DLCxF) artery and vein functioned as interposition vascular conduits in five cases. Superficial forearm vein grafts were used in one case. One patient needed flap re-exploration due to venous congestion. One patient had partial flap necrosis due to delayed infection, and one developed delayed wound dehiscence in the irradiated wound. The average follow-up was 18 months. CONCLUSION: The FHR flap has consistent vascular anatomy. It can be raised as an anterograde or retrograde flap for a contralateral or ipsilateral inset. FHR flap can be used in extensive composite nasal defects. This case series demonstrates that interposition vascular grafts are invariably needed and the possibility of using forearm vessels as grafts instead of DLCxF artery and vein.

Comparing right colon adenoma detection rate during water exchange and air insufflation: a double-blind randomized controlled trial.

BACKGROUND: Randomized controlled trials (RCTs) have reported that water exchange (WE) produced the highest adenoma detection rate (ADR) but did not evaluate right colon adenoma detection rate (rADR) as a primary outcome and only one of the trials employed blinded colonoscopists. The aim of our study was to determine whether, compared with air insufflation, WE significantly increases rADR and right colon serrated lesion detection rate (rSLDR) and decreases adenoma miss rate (rAMR). METHODS: This prospective, double-blind RCT was conducted at a regional hospital in Taiwan between December 2015 and February 2020. Standard WE and air insufflation were performed. After cecal intubation, the second blinded endoscopist examined the right colon and obtained rADR (primary outcome) and rSLDR. Then, the primary colonoscopist reinserted the scope to the cecum with WE in both groups and performed a tandem examination of the right colon to obtain rAMR. RESULTS: There were 284 patients (50.9% male, mean age 58.9 ± 9.4 years) who were randomized to WE (n = 144) or air insufflation (n = 140). The baseline characteristics were similar. The rADR (34.7% vs. 22.3%, p = 0.025), Boston Bowel Preparation Scale scores (mean, 2.6 ± 0.6vs. 2.2 ± 0.6, p < 0.001), rSLDR (18.1% vs. 7.1%, p = 0.007), and rAMR (31.5% vs. 45.2%, p = 0.038) were significantly different between WE and air insufflation. CONCLUSIONS: The current study demonstrated a significantly higher rADR and rSLDR with the WE method performed by blinded colonoscopists. The impact of the significant findings in this report on the occurrence of interval cancers deserves to be studied.

High-power structured laser modes: manifestation of quantum Green's function.

The distributions of resonant frequencies in an astigmatic cavity are theoretically confirmed to be analogously equivalent to the quantum energy structures of two-dimensional commensurate harmonic oscillators. In the first part [Opt. Lett.45, 4096 (2020)OPLEDP0146-959210.1364/OL.399251] of this two-part series study, the lasing modes were verified to reveal a variety of vortex array structures. Here, in the second part of this two-part series study, the lasing modes are confirmed to agree very well with the quantum Green's functions that correspond to a bundle of Lissajous figures in the high-order regime.

High-power structured laser modes: direct generation of a vortex array.

The frequency degeneracy induced by the astigmatism in a nearly hemispherical cavity is originally exploited to generate vortex array laser modes with the output power up to 300 mW. The inhomogeneous Helmholtz equation is employed to derive the wave function for manifesting the characteristics of the lasing modes. The theoretical wave function explicitly reveals the role of the Gouy phase in the formation of vortex arrays. Numerical analyses are further performed to confirm that the thermal lensing effect in the laser crystal assists the lasing transverse order to increase with increasing pump power. It is believed that the high efficiency enables the present laser modes to be useful in the applications of structured vortex beams.

Integral-based parallel algorithm for the fast generation of the Zernike polynomials.

The integral representation of the Zernike radial functions is well approximated by applying the Riemann sums with a surprisingly rapid convergence. The errors of the Riemann sums are found to averagely be not exceed 3 ×10-14, 3.3×10-14, and 1.8×10-13 for the radial order up to 30, 50, and 100, respectively. Moreover, a parallel algorithm based on the Riemann sums is proposed to directly generate a set of radial functions. With the aid of the graphics processing units (GPUs), the algorithm shows an acceleration ratio up to 200-fold over the traditional CPU computation. The fast generation for a set of Zernike radial polynomials is expected to be valuable in further applications, such as the aberration analysis and the pattern recognition.

Generalized wave-packet formulation with ray-wave connections for geometric modes in degenerate astigmatic laser resonators.

The parametric equations for periodic rays in degenerate astigmatic laser resonators are derived in a generalized way. The derived parametric equations clearly reveal the formation of Lissajous geometric modes with phase variation along the propagation. Using the representation of a quantum coherent state, a generalized wave-packet formula is derived to connect with the periodic rays of geometric modes. The derived wave-packet formula is not only validated through comparing with various experimental patterns, but also is directly exploited to manifest the spatial asymmetries of Lissajous lasing modes due to a highly transmissive output coupler.

Wave representation for asymmetric elliptic vortex beams generated from the astigmatic mode converter.

An analytical wave representation is derived to express the asymmetric elliptic vortex beams generated by using an astigmatic mode converter to transform the asymmetric Hermite-Gaussian modes. The effect of the spatial asymmetry on the elliptic vortex beam can be straightforwardly considered in the analytical wave representation. A detailed comparison with experimental intensity patterns and phase structures is made. The good agreement between experimental results and theoretical analyses confirms the characterization and generation of the asymmetric elliptic vortex beams.

Exploring elliptical vortex beams with the spatial damping effect.

A general integral formula is analytically derived to represent the wave function of elliptical vortex modes. The derived formula can be straightforwardly employed to take account of spatial damping to explore vortex structure. Spatial damping is found to cause the central degenerate singularity of the circular vortex mode to be split into several singularities with different topological charges. For the non-circular vortex beam, the influence of spatial damping on the distribution of singularities is not significant. Theoretical analyses are confirmed to agree very well with the experimental measurements.

Underwater polypectomy without submucosal injection for colorectal lesions ≤ 20 mm in size-a multicenter retrospective observational study.

BACKGROUND: Underwater polypectomy (UWP) of large (≥ 20 mm) colorectal lesions is well described, but reports of UWP for lesions ≤ 20 mm in size, which account for > 95% of polyps encountered in routine clinical practice, are limited. We assessed the feasibility of UWP in routine practice across various sites for colorectal lesions ≤ 20 mm in size. METHODS: A multicenter retrospective study was performed on pooled data from nine colonoscopists at 3 U.S., 1 Taiwanese and 2 Italian sites. Outcomes related to UWP on lesions ≤ 20 mm in size were analyzed. RESULTS: In 117 patients, UWP netted 169 lesions. Polypectomy by hot (HSP, 54%) or cold (CSP, 41%) snare, and cold forceps (CFP, 5%) were performed successfully without endoscopic evidence of residual neoplasia or immediate clinically significant adverse events. The majority (74.6%) were tubular adenomas; 60.9% were from the proximal colon. Histopathologic margins were positive in 4 and unavailable in 26 CSP and 24 HSP specimens. The remainder had negative resection margins on pathologic reports. CONCLUSION: UWP for colorectal lesions ≤ 20 mm in routine practice across multiple sites confirms the feasibility and acceptability of this technique. Improvement of resection outcomes by UWP in routine practice deserves further evaluation in a randomized controlled trial.

Origin of continuous curves and dotted spots in laser transverse modes with geometric structures.

The transverse structures of geometric modes in degenerate laser resonators with large astigmatism are systematically investigated by starting from the Gaussian wave packet formulation with ray-wave connections. The overlapping degree D between Gaussian wave packets is derived as an analytic expression that manifests the critical overlapping with D=1. The transverse patterns are confirmed to display a structure of continuous curves or dotted spots, depending on D>1 or D<1, respectively. A thorough comparison between experimental results and numerical calculations is performed to validate the theoretical analysis.

Characterization and generation of high-power multi-axis vortex beams by using off-axis pumped degenerate cavities with external astigmatic mode converter.

The generalized geometric mode with several high-order Hermite-Gaussian (HG) beams localized on ray periodic orbits in the degenerate resonator is generated by an off-axis pumped Nd:YVO4 laser, by performing beam transformation via an astigmatic mode converter, the generalized geometric modes are found that can be converted into the multi-axis vortex beams with the bundled-rings structures. Experimental results reveal that the generated multi-axis vortex beams can preserve quite stable beam structures even under high-power operation. Moreover, the radius of the bundled rings for the multi-axis vortex beams can be flexibly adjusted by the off-axis pumping to lead to vortex structures with easily controlled orbital angular momentum distribution. The good agreement between the experimental and theoretical results of propagation evolution for the astigmatic transformation of generalized geometric modes further verify the feasibility of using the proposed system to realize various high-powered, multi-center vortex beams with good reliability and predictability.

Generating high-power asymmetrical Laguerre-Gaussian modes and exploring topological charges distribution.

We employ an off-axis pumped Nd:YVO4 laser and control the reflectance of output coupler to directly generate asymmetrical Hermite-Gaussian (HG) modes with various transverse orders. By using an astigmatic mode converter, the generated asymmetrical HG modes are straightforwardly transformed into asymmetrical Laguerre-Gaussian (LG) modes with a crescent-like shape. The average output power of all the crescent-shaped LG modes can exceed 1W at the pump power of 4W. Furthermore, experimental results are theoretically verified by resonant modes derived from the inhomogeneous Helmholtz equation with the localized source distribution. Theoretical resonant modes are also used to explore the dependence of the phase structures of LG modes on the system loss. As the loss increases, it is found that the singularities at the origin will be rearranged and new singularities are formed in the outside region with average orbital angular momentum remaining unchanged.

Mobile nucleic acid amplification testing (mobiNAAT) for Chlamydia trachomatis screening in hospital emergency department settings.

Management of curable sexually-transmitted infections (STI) such as Chlamydia can be revolutionized by highly sensitive nucleic acid testing that is deployable at the point-of-care (POC). Here we report the development of a mobile nucleic acid amplification testing (mobiNAAT) platform utilizing a mobile phone and droplet magnetofluidics to deliver NAAT in a portable and accessible format. By using magnetic particles as a mobile substrate for nucleic acid capture and transport, fluid handling is reduced to particle translocation on a simple magnetofluidic cartridge assembled with reagents for nucleic acid purification and amplification. A mobile phone user interface operating in tandem with a portable Bluetooth-enabled cartridge-processing unit facilitates process integration. We tested 30 potentially Chlamydia trachomatis (CT)-infected patients in a hospital emergency department and confirmed that mobiNAAT showed 100% concordance with laboratory-based NAAT. Concurrent evaluation by a nontechnical study coordinator who received brief training via an embedded mobile app module demonstrated ease of use and reproducibility of the platform. This work demonstrates the potential of mobile nucleic acid testing in bridging the diagnostic gap between centralized laboratories and hospital emergency departments.

Extracting trajectory equations of classical periodic orbits from the quantum eigenmodes in two-dimensional integrable billiards.

The trajectory equations for classical periodic orbits in the equilateral-triangular and circular billiards are systematically extracted from quantum stationary coherent states. The relationship between the phase factors of quantum stationary coherent states and the initial positions of classical periodic orbits is analytically derived. In addition, the stationary coherent states with noncoprime parametric numbers are shown to correspond to the multiple periodic orbits, which cannot be explicable in the one-particle picture. The stationary coherent states are further verified to be linked to the resonant modes that are generally observed in the experimental wave system excited by a localized and unidirectional source. The excellent agreement between the resonant modes and the stationary coherent states not only manifests the importance of classical features in experimental systems but also paves the way to manipulate the mesoscopic wave functions localized on the periodic orbits for applications.

Exploiting broad-area surface emitting lasers to manifest the path-length distributions of finite-potential quantum billiards.

Broad-area vertical-cavity surface-emitting lasers (VCSELs) with different cavity sizes are experimentally exploited to manifest the influence of the finite confinement strength on the path-length distribution of quantum billiards. The subthreshold emission spectra of VCSELs are measured to obtain the path-length distributions by using the Fourier transform. It is verified that the number of the resonant peaks in the path-length distribution decreases with decreasing the confinement strength. Theoretical analyses for finite-potential quantum billiards are numerically performed to confirm that the mesoscopic phenomena of quantum billiards with finite confinement strength can be analogously revealed by using broad-area VCSELs.

Targeting post-translational modifications of histones for cancer therapy.

Post-translational modifications (PTMs) on histones including acetylation, methylation, phosphorylation, citrullination, ubiquitination, ADP ribosylation, and sumoylation, play important roles in different biological events including chromatin dynamics, DNA replication, and transcriptional regulation. Aberrant histones PTMs leads to abnormal gene expression and uncontrolled cell proliferation, followed by development of cancers. Therefore, targeting the enzymes required for specific histone PTMs holds a lot of potential for cancer treatment. In this review article, we retrospect the latest studies in the regulations of acetylation, methylation, and phosphorylation of histones. We also summarize inhibitors/drugs that target these modifications for cancer treatment.

Clinical manifestations in patients with alpha-fetoprotein-producing gastric cancer.

BACKGROUND: Patients with alpha-fetoprotein (afp)-producing gastric cancer have a high incidence of liver metastasis and poor prognosis. There is some controversy about clinical manifestations in these patients. METHODS: Our study enrolled patients who, before surgery, had gastric cancer with serum afp exceeding 20 ng/mL [afp>20 (n = 58)] and with serum afp 20 ng/mL or less [afp≤20 (n = 1236)]. Clinical manifestations were compared between the groups. RESULTS: Early gastric cancer was more frequent (30.1% vs. 4%) and advanced gastric cancer was less frequent (69.9% vs. 96%) in the afp≤20 group than the afp>20 group (p < 0.001). Liver and lymph node metastasis occurred less frequently in the afp≤20 group (4.4% vs. 27.6%, p < 0.001, and 60.7% vs. 91.4%, p < 0.001, respectively). The 1-, 3-, 5-, and 10-year survival rates of afp≤20 patients were 75.2%, 53.4%, 45.8%, and 34.6% respectively. The 1-, 3-, 5-, and 10-year survival rates of patients with afp greater than 20 ng/mL, but 300 ng/mL or less, were 46.7%, 28.9%, 17.8%, and 13.3% respectively. The 1-, 3-, and 5-year survival rates of patients with serum afp greater than 300 ng/mL were 15.4%, 7.7%, and 0% respectively. The independent predictors for survival time were afp concentration, age, peritoneal seeding, liver metastasis, lymph node metastasis, vascular invasion, TNM stage, curative surgery, serosal invasion, and Lauren classification. CONCLUSIONS: Patients with high serum afp had a high frequency of liver and lymph node metastasis and very poor prognosis. More aggressive management with multimodal therapy (for example, chemotherapy, radiotherapy) might be needed when treating such patients.

Emergency department (ED) utilization by HIV-infected ED patients in the United States in 2009 and 2010 - a national estimation.

OBJECTIVES: The aim of the study was to describe the emergency department (ED) resource utilization patterns of ED visits by patients reported to be HIV-infected in the USA in 2009 and 2010 and to compare them with those of the general ED patient population. METHODS: We identified demographics, HIV infection status, and ED utilization patterns in 2009 and 2010 from a weighted sample of US ED visits using the National Hospital Ambulatory Medical Care Survey, a nationally representative survey. Data on visits by patients aged ≥ 13 years were analysed using procedures for multiple-stage survey data. RESULTS: In 2009 and 2010, 1 192 535 visits were documented for HIV-infected patients. The estimated annual ED visit rates were 633 per 1000 known HIV-infected persons and 438 per 1000 non-HIV-infected persons [rate difference 195; 95% confidence interval (CI) 194, 197]. While no difference was recorded in the level of acuity between HIV-infected ED patients and general ED patients, the total number of diagnostic/screening services ordered and medications administered in the ED was significantly higher for visits by HIV-infected patients. HIV-infected patients making ED visits also had a longer duration of stays [mean 5.4 h (95% CI 4.6, 6.2 h) vs. 3.6 h (95% CI 3.5, 3.8 h) for HIV-uninfected patients] and were more likely to be admitted [28% (95% CI 22, 34%) vs. 15% (95% CI 14, 16%), respectively] than their non-HIV-infected counterparts. CONCLUSIONS: ED visits by HIV-infected individuals occur at rates higher than those of visits by the general population, and consume significantly more ED resources than visits by the general population. These national findings represent baseline prior to full implementation of the 2010 Patient Protection and Affordable Care Act.