Biological cell trapping and manipulation of a photonic nanojet by a specific microcone-shaped optical fiber tip.

Trapping and manipulating mesoscopic biological cells with high precision and flexibility are very important for numerous biomedical applications. In particular, a photonic nanojet based on a non-resonance focusing phenomenon can serve as a powerful tool for manipulating red blood cells and tumor cells in blood. In this study, we demonstrate an approach to trap and drive cells using a high-quality photonic nanojet which is produced by a specific microcone-shaped optical-fiber tip. The dynamic chemical etching method is used to fabricate optical-fiber probes with a microcone-shaped tip. Optical forces and potentials exerted on a red blood cell by a microcone-shaped fiber tips are analyzed based on finite-difference time-domain calculations. Optical trapping and driving experiments are done using breast cancer cells and red blood cells. Furthermore, a cell chain is formed by adjusting the magnitude of the optical force. The real-time backscattering intensities of multiple cells are detected, and highly sensitive trapping is achieved. This microcone-shaped optical fiber probe is potentially a powerful device for dynamic cell assembly, optical sorting, and the precise diagnosis of vascular diseases.

A new classification of periampullary diverticulum: cannulation of papilla on the inner margins of the diverticulum (Type IIa) is more challenging.

BACKGROUND: Periampullary diverticulum (PAD) may make the performance of endoscopic retrograde cholangiopancreatography (ERCP) in patients with choledocholithiasis more difficult and may increase complication rates. The present study evaluated the effects of PAD on first-time ERCP in patients with choledocholithiasis. METHODS: Outcomes were compared in patients with and without PAD and in those with four types of PAD: papilla located completely inside the diverticulum (type I), papilla located in the inner (type II a) and outer (type II b) margins of the diverticulum; and papilla located outside the diverticulum (type III). Parameters compared included cannulation time and rates of difficult cannulation, post-ERCP pancreatitis (PEP) and perforation. RESULTS: The median cannulation times in patients with types I, II a, II b, III PAD and in those without PAD were 2.0 min, 5.0 min, 0.67 min, 3.5 min, and 3.5 min, respectively, with difficult cannulation rates in these groups of 7.4%, 31.4%, 8.3%, 18.9%, and 23.2%, respectively. The rates of PEP in patients with and without PAD were 5.3% and 5.1%, respectively. Four patients with and one without PAD experienced perforation. CONCLUSIONS: The division of PAD into four types may be more appropriate than the traditional division into three types. Cannulation of type I and II b PAD was easier than cannulation of patients without PAD, whereas cannulation of type II a PAD was more challenging. PAD may not increase the rates of PEP.

Ti3C2Txnanohybrids: tunable local conductive network and efficient EMI shielding performance for multifunctional materials and devices.

Ti3C2Txis an important member of the MXenes family. Due to its excellent electrical conductivity, adjustable atomic layer, and modifiable active surface, Ti3C2Txhas attracted great attention in the field of electromagnetic interference (EMI) shielding. This paper introduces the important role of regulating conductive network to improve the EMI shielding performance of materials and summarizes the EMI shielding performance of Ti3C2Txnanohybrids reported in recent years. In addition, Ti3C2Txbased EMI shielding materials towards multifunctional devices are also systematically introduced. After that, the development status of Ti3C2Txnanohybrids in the field of EMI shielding is objectively described, and the main problems and challenges are evaluated. Finally, the prospect of Ti3C2Txnanohybrids for advanced and green EMI shielding materials is forecasted.

Correction to: Exosomal miR-21 regulates the TETs/PTENp1/PTEN pathway to promote hepatocellular carcinoma growth.

Following the publication of article [1], the authors found that the images of Transwell Matrigel invasion (Fig. 7d) are incorrect.

Exosomal miR-21 regulates the TETs/PTENp1/PTEN pathway to promote hepatocellular carcinoma growth.

BACKGROUND: As an important means of communication, exosomes play an important role in the development of hepatocellular carcinoma (HCC). METHODS: Bioinformatics analysis, dual-luciferase reporter assays, methylation-specific quantitative PCR, and ChIP-PCR analysis were used to gain insight into the underlying mechanism of miR-21 in HCC. RESULTS: The detection of miRNAs in exosomes of HCC showed that miR-21 expression in exosomes was positively correlated with the expression level of miR-21 in cells and negatively correlated with the expression of its target genes PTEN, PTENp1 and TETs. HCC cell-derived exosomes could increase miR-21 and p-Akt expression in HCC cells and downregulate the expression of PTEN, PTENp1 and TETs. MiR-21 inhibitors or PTENp1 overexpression vectors could weaken the effect of the abovementioned exosomes and simultaneously weaken their role in promoting cell proliferation and migration and inhibiting apoptosis. Further studies showed that miR-21 not only directly regulated the expression of PTEN, PTENp1 and TETs but also increased the methylation level of the PTENp1 promoter by regulating the expression of TETs, thereby inhibiting the expression of PTENp1 and further downregulating the expression of PTEN. CONCLUSIONS: Exosomal miR-21 can regulate the expression of the tumor suppressor genes PTEN and PTENp1 in various ways and affect the growth of HCC cells.

Effect of balloon dilation eustachian tuboplasty combined with tympanic tube insertion in the treatment of chronic recurrent secretory otitis media.

PURPOSE: To investigate the long-term clinical effect of balloon dilation eustachian tuboplasty (BET) combined with tympanic tube insertion (TTI) in the treatment of chronic recurrent secretory otitis media (CRSOM). MATERIALS AND METHODS: A retrospective study of 30 cases of CRSOM treated with BET combined with TTI under general anesthesia between August 2014 and September 2016. Thirty cases of CRSOM treated with TTI in the same period were taken as the control group. All cases were followed over 24 months. The scores of eustachian tube (ET) function preoperation, 1 month, 6 months, 12 months, and 24 months postoperation were collected and analyzed, respectively. A satisfaction questionnaire was used to evaluate the therapy at 24-months postoperation. RESULTS: The symptoms were significantly improved and the ET score was obviously increased postsurgery in most cases treated with BET plus TTI compared with those treated with TTI alone. The highest ET score was obtained at 6 months post BET. Five (14%) cases (6 ears) of CRSOM recurred. The 24-month postoperation follow-up questionnaire showed that 84.6% of the patients were satisfied with the treatment, while ten cases (25%) in the TTI group recurred. CONCLUSION: BET combined with TTI surgery is an effective therapy for patients with CRSOM.

Round Window Niche Drilling with Intratympanic Steroid Is a Salvage Therapy of Sudden Hearing Loss.

OBJECTIVE: To explore the effectiveness and safety of round window niche drilling combined with intratympanic methylprednisolone injection for the salvage treatment of sudden sensorineural hearing loss (SSNHL) and its associated tinnitus after failed primary treatment. METHOD: SSNHL patients who showed a less than 10-dB improvement of pure-tone average after receiving standard systemic treatment and intratympanic steroid injection were enrolled. All included patients were randomly divided into two groups (control and study). Patients in the study group received round window niche drilling combined with daily intratympanic methylprednisolone for 7 times; the control group received only daily intratympanic methylprednisolone for 7 times. One month after treatment, the improvements of PTA, speech discrimination score (SDS), tinnitus and the incidence of adverse events were analyzed. RESULTS: 20 patients (10 for each group) were included in this study. The baseline between two groups showed no statistical significance. Patients in the study group experienced an average hearing improvement of 20.38 dB, SDS 19.3 compared with 2.1 dB and SDS 2.0 in the control group. None (0%) in the control group and 4 patients (40%) showed marked recovery, 5 patients (50%) showed slight improvement of hearing in the study group after 1 month. All patients in the study group showed significant recovery of tinnitus. Both tinnitus handicap inventory and a symptom visual analogue scale between two groups revealed statistical differences (p < 0.001, p = 0.002, respectively). None in the control and study groups experienced vertigo, infection and facial paralysis. CONCLUSION: Round window niche drilling increases the contact area and time of methylprednisolone. It is an effective and safe salvage therapy of idiopathic SSNHL and its induced tinnitus.

Effects of combination of balloon Eustachian tuboplasty with methylprednisolone irrigation on treatment of chronic otitis media with effusion in adults.

PURPOSE: Adult chronic otitis media with effusion (COME) is characterized by Eustachian tube dysfunction and mucosal inflammation, which management has long been a challenge because of high recurrence. This study was to investigate the pathological changes of Eustachian tube mucosa and optimized treatment. MATERIALS AND METHODS: Retrospective study of four groups: I: tympanic paracentesis, II: balloon Eustachian tuboplasty (BET), III: BET plus tympanic paracentesis, IV: BET and tympanic paracentesis with methylprednisolone irrigation. Biopsy of Eustachian tube mucosa was obtained preoperative and 1 month post. Recurrence ratio and Eustachian tube scores (ETS) were used to evaluate the effect of treatments. RESULTS: All patients showed narrowed with edematous and thickened Eustachian tube mucosa. At 1 month post-treatment, BET with methylprednisolone irrigation significantly decreased intraepithelial inflammation and restored the quality of epithelium and cilia. For group II to IV, The recurrence rate was significantly lower in group IV compared with the other two, but only significantly lower in group IV VS group II at 3 months and 6 months, no significant difference at 12 months. The recurrence rate was significantly higher in group I during follow-up. The ETS were improved in group II, III and IV after treatment. At 1 month and 3 months posttreatment, group IV had significant higher ETS compared with other groups (P < 0.05). There was no serious complications occurred. CONCLUSION: Methylprednisolone irrigation could help to recover mucosal function. BET and tympanic paracentesis with methylprednisolone irrigation could be regarded as a good choice for COME in adults, which has less recurrence rate and prompt recovery of ET function.

Impacts of semi-transparent window on reflectance from metallic gratings at oblique incidence.

This work both numerically and experimentally investigates the reflectance from the smooth side of a semi-transparent 508-µm-thick window with metallic gratings attached on the other side. The incident light is oblique and linearly polarized, and its wavelength ranges from 2.5 to 25 µm. Three gratings with various levels of profile complexity and periods are investigated. Influences from the intrinsic material absorption, light refraction, total internal reflection, interference, and diffraction on both the specular and hemispherical reflectance are studied. Moreover, the applicability of effective medium theory to our samples is verified.

In-plane scattering patterns from a complex dielectric grating at the normal and oblique incidence.

The in-plane scattering patterns from a complex dielectric grating were both numerically and experimentally studied in contrast to those from well-known metallic gratings. The incidence was the transverse electric or transverse magnetic wave of wavelength λ=660 nm. The grating profile was complex with a period Λ=7.0 µm, while the material was lightly doped crystalline silicon. Patterns of the electric field, magnetic field, and spatial intensity distribution were demonstrated at the normal (θ(i)=0°) and oblique (θ(i)=+30°) incidence. Electric and magnetic fields were presented in the near field as well as the far field. The measured power ratio within -90°≤θ(r)≤+90° was plotted. Their major peaks and the numerically obtained diffraction efficiency of 21 orders (-10≤m≤+10 or -15≤m≤+5) of diffracted waves occurred at the same θ(r). Other peaks and stair-like shoulders of major peaks also exhibited in spectra.

Trapping mid-infrared rays in a lossy film with the Berreman mode, epsilon near zero mode, and magnetic polaritons.

Triple mechanisms were employed to trap mid-infrared (mid-IR) rays within a semi-transparent SiO(2) film sandwiched between gold gratings and a gold substrate. Dimensions of four absorbers were explicitly determined using an LC (inductor-capacitor) circuit model considering the role transition of SiO(2) film. The film behaves as a capacitance and an inductance when the real part of relative electric permittivity for SiO(2) is positive and negative, respectively. At the normal incidence of transverse magnetic waves, every absorptance spectrum of absorbers showed a peak at wavelength λ = 10 µm due to the first mode excitation of magnetic polaritons (MP). At oblique incidence, the Berreman mode led to another peak at λ = 8 µm while its bandwidth was expanded with epsilon near zero mode excited by diffracted waves. The full-width-at-half-maximum of both peaks exceeded 0.6 µm thanks to the SiO(2) loss. Other minor absorptance peaks in the mid-IR were caused by variants of the same MP mode.

Autologous meatal skin graft implantation and intratympanic injection of Pseudomonas aeruginosa: a new experimental mouse model of acquired middle ear cholesteatoma.

AIM: To create an experimental model for the biomedical research of middle ear cholesteatoma. METHODS: Cholesteatoma was induced in the right ears of mice. An autologous meatal skin graft was implanted into the middle ear via the tympanic membrane followed by an intratympanic injection of Pseudomonas aeruginosa. Six weeks after surgery, the formation of acquired cholesteatoma was evaluated by macroscopic examination, CT scan, and histological analysis. The expressions of TNF-α, IL-1ß, and IL-6 were measured with real-time PCR. Auditory-evoked brain stem response was used for assessing the changes in hearing levels. RESULTS: None of the mice died during the modeling time. By the sixth postoperative week, cholesteatoma had successfully formed in 23 out of 25 mice, which equals a success rate of 92%. A CT scan revealed that the cholesteatoma was eroding the cochlea. Furthermore, histological analysis demonstrated a cystic structure covered by stratified squamous epithelium and keratin desquamation in the lamellae inside the cystic cavity in the bullae. All mice with experimentally induced cholesteatoma showed hearing impairment and an upregulated expression of TNF-α, IL-1ß, and IL-6. CONCLUSION: The present study successfully developed a mouse model of acquired middle ear cholesteatoma, which provides an extremely valuable tool for auditory and biomedical research. The modeling approach is technically easy and has a high success rate.

Different Effects and Mechanisms of Selenium Compounds in Improving Pathology in Alzheimer's Disease.

Owing to the strong antioxidant capacity of selenium (Se) in vivo, a variety of Se compounds have been shown to have great potential for improving the main pathologies and cognitive impairment in Alzheimer's disease (AD) models. However, the differences in the anti-AD effects and mechanisms of different Se compounds are still unclear. Theoretically, the absorption and metabolism of different forms of Se in the body vary, which directly determines the diversification of downstream regulatory pathways. In this study, low doses of Se-methylselenocysteine (SMC), selenomethionine (SeM), or sodium selenate (SeNa) were administered to triple transgenic AD (3× Tg-AD) mice for short time periods. AD pathology, activities of selenoenzymes, and metabolic profiles in the brain were studied to explore the similarities and differences in the anti-AD effects and mechanisms of the three Se compounds. We found that all of these Se compounds significantly increased Se levels and antioxidant capacity, regulated amino acid metabolism, and ameliorated synaptic deficits, thus improving the cognitive capacity of AD mice. Importantly, SMC preferentially increased the expression and activity of thioredoxin reductase and reduced tau phosphorylation by inhibiting glycogen synthase kinase-3 beta (GSK-3ß) activity. Glutathione peroxidase 1 (GPx1), the selenoenzyme most affected by SeM, decreased amyloid beta production and improved mitochondrial function. SeNa improved methionine sulfoxide reductase B1 (MsrB1) expression, reflected in AD pathology as promoting the expression of synaptic proteins and restoring synaptic deficits. Herein, we reveal the differences and mechanisms by which different Se compounds improve multiple pathologies of AD and provide novel insights into the targeted administration of Se-containing drugs in the treatment of AD.

[Compositional Characteristics of Volatile Organic Compounds in Typical Industrial Areas of the Pearl River Delta: Importance of Oxygenated Volatile Organic Compounds].

Volatile organic compounds (VOCs) are key components of tropospheric chemistry, of which industrial emissions are an important source of atmospheric VOCs. In this study, online measurements of 74 VOCs were made in a typical industrial area of the Pearl River Delta in southern China during the early summer of 2021. The mean volume mixing ratio of total volatile organic compounds (TVOC) was (81.9±45.4)×10-9 during the campaign. Among them, oxygenated volatile organic compounds (OVOCs) accounted for the largest fraction of TVOC, with an average of 51.5%, followed by aromatics, accounting for 19.4% of TVOC. The proportion of OVOCs in TVOC gradually increased with the increase in TVOC concentration. Industry-related emissions were the main contributors to aromatics and OVOCs in this region. Aromatics and OVOCs were the two major contributors to the ozone formation potential (OFP), accounting for 56.4% and 26.7%, respectively. Furthermore, OVOCs also contributed 40.0% of the total ·OH reactivity from VOCs. Xylenes, toluene, acrolein, and ethyl acetate had a greater contribution to the formation of secondary pollution; thus, these species should be given priority for controlling secondary pollution. Our results underscore the severity of OVOCs pollution in industrial areas and the important roles of OVOCs in secondary pollution.

Development of a polarization-insensitive thermophotovoltaic emitter with a binary grating.

A wavelength-selective but polarization-insensitive thermophotovoltaic emitter was numerically developed with a binary tungsten grating and its appealing emittance spectra were demonstrated with analysis. Ranges of emitter dimensions were preliminarily confined with the excitation of the surface plasmon polariton, cavity resonance, and Wood's anomaly at specified wavelengths. Then, a hybrid scheme (the rigorous coupled wave analysis together with a genetic algorithm) was able to finely tailor the grating profile such that emittance could be significantly enhanced in the near infrared region. The peak emittance at the transverse electric and transverse magnetic polarizations was 0.997 and 0.935, respectively. The emittance was actually almost twice that from a plain tungsten plate at short wavelengths but significantly reduced at long wavelengths. Moreover, such spectral emittance is insensitive to the polarization and 5% dimension modification, making the emitter ideal for thermophotovoltaic applications. Patterns of electromagnetic fields and Poynting vectors were able to confirm the excitation of physical mechanisms.

Second-order derivatives of optical path length of ray with respect to variable vector of source ray.

A method is proposed for determining the second-order derivatives (i.e., the Hessian matrix) of the optical path length of a ray with respect to the variable vector of the source ray in an optical system comprising both flat and spherical boundary surfaces. Several wavefront aberration problems are investigated using the Hessian matrix proposed in this study and the Jacobian (first-order derivatives) matrix presented in the literature. It is found that when using the Hessian matrix the precision of wavefront aberration is significantly improved when evaluated up to the quadratic term of the Taylor series expansion. The methodology proposed in this study not only provides the means to investigate the principal curvatures of the wavefront along a ray, but also yields the information required to determine the irradiance and caustics of both axisymmetric and nonaxisymmetric optical systems.

Osseointegration technique in patients with acquired auricular deformities and failed previous reconstruction: a retrospective study of long-term follow-up and Chinese experience.

OBJECTIVES: To evaluate the complication rate and patient satisfaction of reconstruction of acquired auricular deformities and failed previous reconstruction by the osseointegration technique. METHODS: The study enrolled 24 patients from January 2002 to December 2005. Data collected included demographic information, success rate of auricular prostheses, site of implants, survival rate of implants, occurrence of skin reaction and condition of the prosthetic ear. RESULTS: Twenty-five ears (24 patients) were implanted. All ears were healing well with a lifelike appearance, stable fixation and natural color; except for 2 instances of implants dislocated by trauma, the rest survived well by first intention; skin reaction was the most troublesome complication, no patient was able to maintain a consistent level of soft-tissue health for the whole follow-up period, but the ratio and degree of skin reaction decreased gradually. The time of wearing prosthetic ears was more than 8 h/day. The average time length until prosthetic ear replacement was 3.5 years. There were no intracranial or systemic complications. CONCLUSION: The osseointegration technique can be the method of choice for acquired auricular defects and failed reconstructions. Follow-up management is important to the health of the implants and the surrounding soft tissue and to preserve the prosthesis and its retention mechanism.

Cryptographic scheme using genetic algorithm and optical responses of periodic structures.

This study employed the optical responses of periodic structures, multiple-variable functions with sufficient complexity, to develop a cryptographic scheme. The characteristics of structures could be delivered easily with the ciphertext, a series of numbers containing plaintext messages. Two optimization methods utilizing a genetic algorithm were adopted to generate the periodic structure profile as a critical encryption/decryption key. The robustness of methods was further confirmed under various limits. The ciphertext could only be decrypted by referring to the codebook after acquiring the pre-determined optical response. The confidentiality and large capacity of the scheme revealed the enhanced coding strategies here while the success of the scheme was demonstrated with the delivery of an example message.