Nonlinear edge enhancement imaging based on Laguerre-Gaussian superimposed vortex filters.

Nonlinear reconstruction, which is based on the principle of cross correlation, is a commonly employed reconstruction technique in incoherent correlated digital holography systems. However, the modulation of phase masks in these systems is suppressed during the reconstruction process, resulting in an inability to express the characteristics of the phase masks. Consequently, achieving edge enhancement within these systems is constrained. We propose a nonlinear reconstruction method utilizing Laguerre-Gaussian superimposed vortex filters, which modulates the spectrum of the target during the reconstruction process. Experimental results demonstrate that this method performs well in reconstructing image edges for various phase-masked incoherent imaging systems and effectively suppresses noise. Additionally, this method enables directional edge enhancement.

Oral micronized progesterone versus vaginal progesterone for luteal phase support in fresh embryo transfer cycles: a multicenter, randomized, non-inferiority trial.

STUDY QUESTION: Does oral micronized progesterone result in a non-inferior ongoing pregnancy rate compared to vaginal progesterone gel as luteal phase support (LPS) in fresh embryo transfer cycles? SUMMARY ANSWER: The ongoing pregnancy rate in the group administered oral micronized progesterone 400 mg per day was non-inferior to that in the group administered vaginal progesterone gel 90 mg per day. WHAT IS KNOWN ALREADY: LPS is an integrated component of fresh IVF, for which an optimal treatment regimen is still lacking. The high cost and administration route of the commonly used vaginal progesterone make it less acceptable than oral micronized progesterone; however, the efficacy of oral micronized progesterone is unclear owing to concerns regarding its low bioavailability after the hepatic first pass. STUDY DESIGN, SIZE, DURATION: This non-inferiority randomized trial was conducted in eight academic fertility centers in China from November 2018 to November 2019. The follow-up was completed in April 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 1310 infertile women who underwent their first or second IVF cycles were enrolled. On the day of hCG administration, the patients were randomly assigned to one of three groups for LPS: oral micronized progesterone 400 mg/day (n = 430), oral micronized progesterone 600 mg/day (n = 440) or vaginal progesterone 90 mg/day (n = 440). LPS was started on the day of oocyte retrieval and continued till 11-12 weeks of gestation. The primary outcome was the rate of ongoing pregnancy. MAIN RESULTS AND THE ROLE OF CHANCE: In the intention-to-treat analysis, the rate of ongoing pregnancy in the oral micronized progesterone 400 mg/day group was non-inferior to that of the vaginal progesterone gel group [35.3% versus 38.0%, absolute difference (AD): -2.6%; 95% CI: -9.0% to 3.8%, P-value for non-inferiority test: 0.010]. There was insufficient evidence to support the non-inferiority in the rate of ongoing pregnancy between the oral micronized progesterone 600 mg/day group and the vaginal progesterone gel group (31.6% versus 38.0%, AD: -6.4%; 95% CI: -12.6% to -0.1%, P-value for non-inferiority test: 0.130). In addition, we did not observe a statistically significant difference in the rate of live births between the groups. LIMITATIONS, REASONS FOR CAUTION: The primary outcome of our trial was the ongoing pregnancy rate; however, the live birth rate may be of greater clinical interest. Although the results did not show a difference in the rate of live births, they should be confirmed by further trials with larger sample sizes. In addition, in this study, final oocyte maturation was triggered by hCG, and the findings may not be extrapolatable to cycles with gonadotropin-releasing hormone agonist triggers. WIDER IMPLICATIONS OF THE FINDINGS: Oral micronized progesterone 400 mg/day may be an alternative to vaginal progesterone gel in patients reluctant to accept the vaginal route of administration. However, whether a higher dose of oral micronized progesterone is associated with a poorer pregnancy rate or a higher rate of preterm delivery warrants further investigation. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by a grant from the National Natural Science Foundation of China (82071718). None of the authors have any conflicts of interest to declare. TRIAL REGISTRATION NUMBER: This trial was registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/) with the number ChiCTR1800015958. TRIAL REGISTRATION DATE: May 2018. DATE OF FIRST PATIENT'S ENROLMENT: November 2018.

Focusing through scattering media by a single polarization transmission matrix with binary polarization modulation.

Wavefront distortion induced by scattering media seriously affects optical focusing. Wavefront shaping based on a transmission matrix (TM) is useful in controlling light propagation in highly scattering media. Traditional TM generally studies amplitude and phase, but the stochastic nature of the light propagation in the scattering medium also affects its polarization. Based on the binary polarization modulation, we propose a single polarization transmission matrix (SPTM) and achieve single-spot focusing through scattering media. We anticipate that the SPTM will be widely used in wavefront shaping.

Recording point spread functions by wavefront modulation for interferenceless coded aperture correlation holography.

Coded aperture correlation holography (COACH) needs the point spread function (PSF) for image reconstruction. Utilizing a pinhole to generate a point light source is the most frequently adopted method for measuring PSF, which, however, has significant issues to resolve. One of the problems is that the resolution of the reconstructed result is limited by the cutoff frequency of the pinhole. The other is that the far-field PSF is undetectable because the amount of light illuminance decreases with the distance. In this work, we present a method for recording the PSF based on wavefront modulation. By modulating a plane wave with both the carrier spherical wave and the coded phase mask, we obtain a virtual point spread function (VPSF) that is used for image reconstruction. It is shown that the resolution of reconstructed results is not limited by the pinhole. We experimentally demonstrate high-resolution reconstruction by the VPSF.

Overexpression of Sugarcane ScDIR Genes Enhances Drought Tolerance in Nicotiana benthamiana.

Dirigent proteins (DIRs) are known to function in lignin biogenesis and to be involved in stress resistance in plants. However, the sugarcane DIRs have not been functionally characterized. In this study, we investigated the DIR-protein-encoding genes in Saccharum spp. (ScDIR) by screening collections of sugarcane databases, monitoring the responses of these genes to drought stress by real-time quantitative PCR, and identifying their heterologous expression in tobacco. Of the 64 ScDIRs identified, four belonging to the DIR-b/d (ScDIR5 and ScDIR11) and DIR-c (ScDIR7 and ScDIR40) subfamilies showed a significant transcriptional response when subjected to drought stress. ScDIR5, ScDIR7, and ScDIR11 are localized in the cell membrane, whereas ScDIR40 is found in the cell wall. The overexpression of these ScDIR genes in tobacco generally increased the drought tolerance of the transgenic lines, with ScDIR7 conferring the highest degree of drought tolerance. The characterization of the physiological and biochemical indicators (superoxide dismutase, catalase, malondialdehyde, and H2O2) confirmed that the ScDIR-overexpressing lines outperformed the wild type. These results demonstrated that specific ScDIRs in sugarcane respond and contribute to tolerance of drought stress, shedding light on potential means of improving drought tolerance in this crop.

Renieramycin T Inhibits Melanoma B16F10 Cell Metastasis and Invasion via Regulating Nrf2 and STAT3 Signaling Pathways.

As one of marine tetrahydroisoquinoline alkaloids, renieramycin T plays a significant role in inhibiting tumor metastasis and invasion. However, the effect of renieramycin T on inflammation-related tumor metastasis and invasion is still unknown, and its mechanisms remain unclear. Here we established an inflammation-related tumor model by using the supernatant of RAW264.7 cells to simulate B16F10 mouse melanoma cells. The results indicate that renieramycin T suppressed RAW264.7 cell supernatant-reduced B16F10 cell adhesion to a fibronectin-coated substrate, migration, and invasion through the matrigel in a concentration-dependent manner. Moreover, Western blot results reveal that renieramycin T attenuated the phosphorylation of STAT3 and down-regulated the expression of Nrf2. Together, the above findings suggest a model of renieramycin T in suppressing B16F10 cancer cell migration and invasion. It may serve as a promising drug for the treatment of cancer metastasis.

Dually acid- and GSH-triggered bis(ß-cyclodextrin) as drugs delivery nanoplatform for effective anticancer monotherapy.

The intrinsic poor solubility and limited load capacity of ß-cyclodextrins (ß-CDs) results in reduced bioavailability, rendering the material unsuitable in complex biological environments. In this work, a pair of ß-CDs was methylated and covalently linked with acid-sensitive acylhydrazone and GSH-sensitive disulfide bonds to ensure a precise drug release pattern. The hydrophobic anticancer drug doxorubicin (Dox) was encapsulated inside the hydrophobic core of bis(ß-CD) via hydrophobic association with loading capacity of 24% in weight and a hydrodynamic size of about 100 nm. When exposed to acidic and reductive environments, the acylhydrazone and disulfide bonds were found to be cleaved, resulting in Dox release. Using fluorescence imaging and flow cytometry analysis, the designed bis(ß-CD) were determined to activate the drug release behavior by specific intracellular stimuli (pH and GSH). In vivo studies demonstrated specific drug delivery characteristics and controlled drug release behaviors in the tumor sites, giving rise to high antitumor activity and low toxicity. Taken in concert, this dual stimuli-responsive bis(ß-CD) with superior amphiphilicity and biocompatibility features showed great potential for future clinical applications.

Angiogenesis effects of 4-methoxy benzyl alcohol on cerebral ischemia-reperfusion injury via regulation of VEGF-Ang/Tie2 balance.

Angiogenesis facilitates the formation of microvascular networks and promotes neurological deficit recovery after cerebral ischemia-reperfusion injury (CIRI). This study investigated the angiogenesis effects of 4-methoxy benzyl alcohol (4-MA) on CIRI. The angiogenesis effects of 4-MA and the potential underlying mechanisms were assessed based on a middle cerebral artery occlusion/reperfusion (MCAO/R) rat model and a hind limb ischemic (HLI) mouse model. Immunofluorescence was conducted to detect microvessel density, and Western blotting and polymerase chain reaction were performed to determine the expression of angiogenesis-promoting factors. In addition, we investigated whether the angiogenesis effects of 4-MA caused damage to the blood-brain barrier (BBB). After treatment with 4-MA (20 mg/kg) for 7 days, the neurological deficits recovered and microvessel density in the cerebral cortex increased in the MCAO/R rats. Additionally, 4-MA also regulated the expression of angiogenesis factors, with an increase in vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor 2 (VEGFR-2) expression and a decrease in angiopoietin 1 (Ang-1), Ang-2, and Tie-2 expression in both MCAO/R rats and HLI mice. Moreover, 4-MA increased the expression of angiogenesis-promoting factors without exacerbating BBB cascade damage in MCAO/R rats. Our results indicated that 4-MA may contribute to the formation of microvascular networks, thus promoting neurological deficit recovery after CIRI.

Efficient compressive holographic reconstruction based on hologram segmentation.

Compressive holography can successfully reconstruct a three-dimensional layered object from a two-dimensional hologram. However, the extremely time-consuming reconstruction limits its range of applications. We propose a dimension reduction of measurement matrix (DRMM) method to accelerate compressive holographic reconstruction. The calculation time is substantially reduced while the reconstruction quality is improved by DRMM, which is implemented by a hologram segmentation approach and a parallel computing technique. Holograms of specific target objects are segmented from the hologram of a three-dimensional layered object, and the reconstruction can be implemented in parallel using multicore processors. We present both simulation and experimental results to show the feasibility and effectiveness of the proposed method.

Wire templated electrodeposition of vessel-like structured chitosan hydrogel by using a pulsed electrical signal.

Herein, by performing a templated electrodeposition process with an oscillating electrical signal stimulation, a vessel-like structured chitosan hydrogel (diameter about 0.4 mm) was successfully prepared in the absence of salt conditions. Experimental results demonstrated that the hydrogel growth (e.g. the thickness) is linearly correlated with the imposed charge transfer and can be well quantified by using a theoretical moving front model. Morphological observations indicated that the heterogeneous multilayer structure was spatially and temporally controlled by an externally employed electrical signal sequence while the channel structure could be determined by the shaped electrode. Moreover, the oscillating ON-OFF cycles were proved to strongly affect the film structure, leading to a more compact hydrogel coating with a lower water content, higher crystallinity, complex layer architecture and relatively strong mechanical properties that could be easily peeled off as a free-standing hollow tube. Importantly, all the experiments were conducted under mild conditions that allowed additional enhancing materials to be added in to further improve the mechanical and/or biological properties. Thus, this work advances a very promising self-assembly technology for the construction of a multi-functional hydrogel coating and artificial blood vessel regeneration.

Preparation and characterization of molecularly imprinted polymers based on ß-cyclodextrin-stabilized Pickering emulsion polymerization for selective recognition of erythromycin from river water and milk.

Molecularly imprinted polymers were prepared via ß-cyclodextrin-stabilized oil-in-water Pickering emulsion polymerization for selective recognition and adsorption of erythromycin. The synthesized molecularly imprinted polymers were spherical in shape, with diameters ranging from 20 to 40 µm. The molecularly imprinted polymers showed high adsorption capacity (87.08 mg/g) and adsorption isotherm data fitted well with Langmuir model. Adsorption kinetics study demonstrated that the molecularly imprinted polymers acted in a fast adsorption kinetic pattern and the adsorption features of molecularly imprinted polymers followed a pseudo-first-order model. Adsorption selectivity analysis revealed that molecularly imprinted polymers had a much better specificity for erythromycin than that for spiramycin or amoxicillin, and the relative selectivity coefficient values on the bases of spiramycin and amoxicillin were 3.97 and 3.86, respectively. The Molecularly imprinted polymers also showed a satisfactory reusability after four times of regeneration. In addition, molecularly imprinted polymers exhibited good adsorption capacities for erythromycin under complicated environment, that is, river water and milk. These results proved that the as-prepared molecularly imprinted polymers is a potent absorbent for selective recognition of erythromycin, and therefore it may be a promising candidate for practical applications, such as wastewater treatment and detection of erythromycin residues in food.

A nanoprobe for ratiometric imaging of glutathione in living cells based on the use of a nanocomposite prepared from dual-emission carbon dots and manganese dioxide nanosheets.

A ratiometric fluorescence assay for glutathione (GSH) was developed. The novel assay is based on a nanoprobe composed of manganese dioxide nanosheets (MnO2 NS) and dual-emission carbon dots (de-CDs) with intrinsic GSH-response property. After construction of the nanoprobe, two emission peaks of de-CDs were suppressed to varying degrees by MnO2 NS. The suppression was relieved and the two emission peaks recovered proportionally when MnO2 NS was decomposed by GSH, thus realizing the ratiometric assay for micromolar GSH. The intrinsic responsiveness of de-CDs to millimolar GSH broadens the analytical range of the nanoprobe. An appropriate precursor, calcon-carboxylic acid, was screened out to synthesize de-CDs via one-step hydrothermal treatment. The de-CD@MnO2 NS nanoprobe can measure GSH concentrations through the fluorescence intensity ratio between 435 and 516 nm excited at 365 nm. The range of response was from 1 µM to 10 mM and the detection limit reached 0.6 µM (3σ criterion). Benefiting from its good biocompatibility, the proposed nanoprobe has excellent applicability for intracellular GSH imaging.Graphical abstract Schematic representation of glutathione (GSH) ratiometric detection. The nanoprobe is prepared from dual-emission carbon dots (de-CDs) and manganese dioxide nanosheets (MnO2 NS). GSH removes quenching effect by decomposing MnO2 NS and induces intrinsic response of de-CDs, which realizes ratiometric detection.

Syphilis associated with recreational drug use, depression and high-risk sexual behaviour in men who have sex with men: a case-control study in China.

OBJECTIVE: We investigated syphilis prevalence among men who have sex with men (MSM) in China, as well as potential risk factors. Our principal hypothesis was that syphilis would be associated with the use of recreational drugs such as methamphetamines. METHODS: From April to October 2013, we used several methods to recruit MSM in Qingdao, collecting demographic/behavioural information via self-administrated questionnaires. Trained health workers collected blood for the Treponema pallidum particle assay (TPPA) with positives confirmed by a toluidine red unheated serum test. We used an unmatched case-control study to identify factors that might predict syphilis infection using multivariable logistic regression. RESULTS: We recruited 447 MSM who agreed to participate and who completed syphilis testing. Of 71 (15.9%) syphilis-positive MSM, 44 (62.0%) used drugs. Of 376 (84.1%) syphilis-negative MSM, 186 (49.5%) used drugs. We found a positive association with syphilis for any recreational drug use (crude OR (cOR) 1.7, 95 % CI 1.0 to 2.8), frequent methamphetamine use (cOR 2.4, 95% CI 1.1 to 5.3) and multiple drug use (adjusted OR (aOR) 3.4, 95% CI 1.3 to 9.2). Syphilis-positive men were more likely to have a higher physical depression score (aOR 5.2, 95% CI 1.1 to 24.4), be > 30 years old (aOR 2.7, 95% CI 1.5 to 4.8), report a prior STI (aOR 4.1, 95% CI 2.3 to 7.3) and report a sex party experience (aOR 2.2, 95% CI 1.1 to 4.4). CONCLUSIONS: Recreational drug use, depression and high-risk sexual behaviours were associated with syphilis infection among MSM in China. Only a multifaceted approach is likely be effective in control of both syphilis and HIV .

Controllable mode transformation in perfect optical vortices.

We report a novel method to freely transform the modes of a perfect optical vortex (POV). By adjusting the scaling factor of the Bessel-Gauss beam at the object plane, the POV mode transformation can be easily controlled from circle to ellipse with a high mode purity. Combined with the modulation of the cone angle of an axicon, the ellipse mode can be freely adjusted along the two orthogonal directions. The properties of the "perfect vortex" are experimentally verified. Moreover, fractional elliptic POVs with versatile modes are presented, where the number and position of the gaps are controllable. These findings are significant for applications that require the complex structured optical field of the POV.

Synthesis of Size-Tunable Hollow Polypyrrole Nanostructures and Their Assembly into Folate-Targeting and pH-Responsive Anticancer Drug-Delivery Agents.

Chemotherapeutic drugs currently used in clinical settings have high toxicity, low specificity, and short half-lives. Herein, polypyrrole-based anticancer drug nanocapsules were prepared by tailoring the size of the nanoparticles with a template method, controlling drug release by means of an aromatic imine, increasing nanoparticle stability through PEGylation, and improving tumor-cell selectivity by folate mediation. The nanoparticles were characterized by TEM and dynamic light scattering. α-Folate receptor expression levelsof tumor cells and normal cells were investigated by western blot and quantitative polymerase chain reaction analyses. Flow cytometry and fluorescence imaging were used to verify the cell uptake of the different-sized nanoparticles. From the different-sized polypyrrole nanoparticles, the optimally functionalized nanoparticles of 180 nm hydrodynamic diameter were chosen and further usedfor in vitroandin vivotests. The nanoparticles showed excellent biocompatibility and the drug-loaded nanoparticles exhibited effective inhibition of tumor cell growth in vitro. Moreover, the drug-loaded nanoparticles showed substantially enhanced accumulation in tumor regions and effectively inhibitedin vivotumor growth. Furthermore, the nanoparticles showed reduced doxorubicin-induced toxicity andno significant side effects in normal organs of tumor-bearing mice, as measured by body-weight shifts and evaluationof drug distribution. Overall, the functionalized nanoparticles are promising nanocarriers for tumor-targeting drug delivery.

Multifunctional halloysite nanotubes for targeted delivery and controlled release of doxorubicin in-vitro and in-vivo studies.

The current state of cancer therapy encourages researchers to develop novel efficient nanocarriers. Halloysite nanotubes (HNTs) are good nanocarrier candidates due to their unique nanoscale (40-80 nm in diamter and 200-500 nm in length) and hollow lumen, as well as good biocompatibility and low cost. In our study, we prepared a type of folate-mediated targeting and redox-triggered anticancer drug delivery system, so that Doxorubicin (DOX) can be specifically transported to tumor sites due to the over-expressed folate-receptors on the surface of cancer cells. Furthermore, it can then be released by the reductive agent glutathione (GSH) in cancer cells where the content of GSH is nearly 103-fold higher than in the extracellular matrix. A series of methods have demonstrated that per-thiol-ß-cyclodextrin (ß-CD-(SH)7) was successfully combined with HNTs via a redox-responsive disulfide bond, and folic acid-polyethylene glycol-adamantane (FA-PEG-Ad) was immobilized on the HNTs through the strong complexation between ß-CD/Ad. In vitro studies indicated that the release rate of DOX raised sharply in dithiothreitol (DTT) reducing environment and the amount of released DOX reached 70% in 10 mM DTT within the first 10 h, while only 40% of DOX was released in phosphate buffer solution (PBS) even after 79 h. Furthermore, the targeted HNTs could be specifically endocytosed by over-expressed folate-receptor cancer cells and significantly accelerate the apoptosis of cancer cells compared to non-targeted HNTs. In vivo studies further verified that the targeted HNTs had the best therapeutic efficacy and no obvious side effects for tumor-bearing nude mice, while free DOX showed damaging effects on normal tissues. In summary, this novel nanocarrier system shows excellent potential for targeted delivery and controlled release of anticancer drugs and provides a potential platform for tumor therapy.

Sexual health status of women who have regular sexual relations with men who have sex with men in mainland China.

BACKGROUND: Men who have sex with men (MSM) are a high-risk group for sexually transmitted diseases (STDs) and human immunodeficiency virus (HIV) infection. In China, the vast majority of MSM feel forced to marry or plan to marry women, according to traditional Chinese culture. Women who have regular sexual relations with MSM, called tongqi in mainland China, live with a high risk of STDs or HIV infection, but these risks are often ignored. Our investigation of this group of the women is a preliminary study that aims to understand the sexual health problems of tongqi and related factors. METHODS: This study relied on website mobilization and was funded by tongqi. Participants were limited to women who had sex with MSM to whom they were married (in-GWs), whom they had divorced (ex-GWs), or with whom they were friends (GGFs). The data were collected using questionnaire software. RESULTS: A total 144 valid surveys were returned from 100 in-GWs, 33 ex-GWs, and 11 GGFs. Average respondent age was 32.8 ± 6.4 years (range 22 to 58 years). Among in-GWs and ex-GWs, over 95% learned that their husbands were MSM after marriage. More than half of respondents had had sex before marriage, and one-third of those women had sex partners other than their husbands. In addition, 35.3% of tongqi had STDs symptoms. About 50% participants had had oral sex with sex partners of MSM and 10% had had passive anal sex, with low condom use during both oral (9.7%) and anal sex (23.1%). Most tongqi had misunderstandings about STDs and HIV and less than 30% had undergone HIV screening. Among participants tested, 5.6% were HIV positive. A total 93.5% of respondents believed that laws should be established to protect the sexual rights of women. CONCLUSIONS: Women who have regular sexual relations with MSM face adverse sexual health issues and are susceptible to STDs and HIV infection. Measures must be taken to protect the rights and interests of tongqi in mainland China.

[Factors affecting the success rate of artificial insemination with donor sperm].

OBJECTIVE: To explore various factors affecting the clinical pregnancy outcomes of artificial insemination with donor sperm (AID). METHODS: We retrospectively analyzed 15,744 cycles of AID in 6302 women and investigated the association of the clinical pregnancy outcomes of AID with the treatment protocols, the times of insemination per cycle, the age of the infertile women, the status of the oviduct, and the number of AID cycles. RESULTS: The pregnancy rate of AID was higher in the chlomiphene-treated women than in those of the natural cycle group (P = 0.003) but showed no significant differences either between the chloramiphene and human menopause gonadotropin (HMG) or between the HMG and natural cycle groups (P > 0.05), and so was it in the women that had received AID twice per cycle before and after ovulation (26.3%) than in those that had undergone only once before (7.0%) or after ovulation (23.7%) (P < 0.05). However, the pregnancy rate was remarkably lower in the women aged 35-40 years (16.5%), especially in those over 40 years (1.2%), than in those under 35 years (26.0%) (P < 0.05). There was no significant difference in the success rate of AID between the women with oviductal adhesion and those without (27.4% vs. 28.1%, P > 0.05). The pregnancy rate of the first cycle of AID (27.6%) was markedly higher than those of the second (24.7%), third (23.9%), and fourth (23.1%) (P < 0.01), but with no significant differences among the latter three cycles (P > 0.05), while that of the fifth cycle (19.0%) was remarkably lower than those of the first four (P < 0.01). CONCLUSION: The age of the infertile women is an important factor affecting the success rate of AID. AID twice per cycle is better than once only. For those without oviductal factors, at least 4 cycles of AID are required before in vitro fertilization.

Introducing rapid oral-fluid HIV testing among high risk populations in Shandong, China: feasibility and challenges.

BACKGROUND: This study was conducted to ascertain the feasibility of using rapid oral fluid testing as an alternative HIV testing method in China. METHOD: This is a mixed-method study among men who have sex with men (MSM), female sex workers (FSW) and VCT clients, conducted in 4 cities in Shandong Province. A pre-tested questionnaire was administered to 1137 participants through face-to-face interview to assess demographic characteristics, HIV testing histories and willingness to accept rapid oral fluid testing. VCT clients were provided with the saliva test kits for a screening test and errors in operation were recorded. Testing results were compared between oral and blood testing. Short feedback questionnaire was administered to 200 FSW who had undergone oral testing. RESULTS: The rate of willingness to take oral-fluid HIV testing among MSM, FSW and VCT clients was 72.8%, 72.1% and 67.4% respectively. Common errors recorded during test kit operation by the 229 VCT clients included: unpreparedness, wrong swab sampling, wrong dilution, wrong testing and inability to read test results. Advantages of oral testing listed by participants included: less intrusive, painlessness, easy self- testing and privacy. Disadvantages included perceived unreliable results (55.5%) and not nationally recognised (9%). Comparison of saliva and the blood testing results recorded a consistency rate of 0.970 (χ2 = 153.348, P < 0.001), implying an excellent consistency. CONCLUSION: Introduction of oral rapid fluid testing as an alternative HIV testing method in China is highly feasible but with some challenges including low recognition and operation errors.

Antheraea pernyi silk fibroin-coated PEI/DNA complexes for targeted gene delivery in HEK 293 and HCT 116 cells.

Polyethylenimine (PEI) has attracted much attention as a DNA condenser, but its toxicity and non-specific targeting limit its potential. To overcome these limitations, Antheraea pernyi silk fibroin (ASF), a natural protein rich in arginyl-glycyl-aspartic acid (RGD) peptides that contains negative surface charges in a neutral aqueous solution, was used to coat PEI/DNA complexes to form ASF/PEI/DNA ternary complexes. Coating these complexes with ASF caused fewer surface charges and greater size compared with the PEI/DNA complexes alone. In vitro transfection studies revealed that incorporation of ASF led to greater transfection efficiencies in both HEK (human embryonic kidney) 293 and HCT (human colorectal carcinoma) 116 cells, albeit with less electrostatic binding affinity for the cells. Moreover, the transfection efficiency in the HCT 116 cells was higher than that in the HEK 293 cells under the same conditions, which may be due to the target bonding affinity of the RGD peptides in ASF for integrins on the HCT 116 cell surface. This result indicated that the RGD binding affinity in ASF for integrins can enhance the specific targeting affinity to compensate for the reduction in electrostatic binding between ASF-coated PEI carriers and cells. Cell viability measurements showed higher cell viability after transfection of ASF/PEI/DNA ternary complexes than after transfection of PEI/DNA binary complexes alone. Lactate dehydrogenase (LDH) release studies further confirmed the improvement in the targeting effect of ASF/PEI/DNA ternary complexes to cells. These results suggest that ASF-coated PEI is a preferred transfection reagent and useful for improving both the transfection efficiency and cell viability of PEI-based nonviral vectors.