High Sensitivity SERS Substrate of a Few Nanometers Single-Layer Silver Thickness Fabricated by DC Magnetron Sputtering Technology.

Surface-enhanced Raman spectroscopy (SERS) is commonly used for super-selective analysis through nanostructured silver layers in the environment, food quality, biomedicine, and materials science. To fabricate a high-sensitivity but a more accessible device of SERS, DC magnetron sputtering technology was used to realize high sensitivity, low cost, a stable deposition rate, and rapid mass production. This study investigated various thicknesses of a silver film ranging from 3.0 to 12.1 nm by field emission scanning electron microscope, X-ray diffraction, and X-ray photoelectron spectroscopy. In the rhodamine 6G (R6G) testing irradiated by a He-Ne laser beam, the analytical enhancement factor (AEF) of 9.35 × 108, the limit of detection (LOD) of 10-8 M, and the relative standard deviation (RSD) of 1.61% were better than the other SERS substrates fabricated by the same DC sputtering process because the results showed that the 6 nm thickness silver layer had the highest sensitivity, stability, and lifetime. The paraquat and acetylcholine analytes were further investigated and high sensitivity was also achievable. The proposed SERS samples were evaluated and stored in a low humidity environment for up to forty weeks, and no spectrum attenuation could be detected. Soon, the proposed technology to fabricate high sensitivity, repeatability, and robust SERS substrate will be an optimized process technology in multiple applications.

Crosstalk between E-Cadherin/ß-Catenin and NF-κB Signaling Pathways: The Regulation of Host-Pathogen Interaction during Leptospirosis.

Approximately 1 million cases of leptospirosis, an emerging infectious zoonotic disease, are reported each year. Pathogenic Leptospira species express leucine-rich repeat (LRR) proteins that are rarely expressed in non-pathogenic Leptospira species. The LRR domain-containing protein family is vital for the virulence of pathogenic Leptospira species. In this study, the biological mechanisms of an essential LRR domain protein from pathogenic Leptospira were examined. The effects of Leptospira and recombinant LRR20 (rLRR20) on the expression levels of factors involved in signal transduction were examined using microarray, quantitative real-time polymerase chain reaction, and western blotting. The secreted biomarkers were measured using an enzyme-linked immunosorbent assay. rLRR20 colocalized with E-cadherin on the cell surface and activated the downstream transcription factor ß-catenin, which subsequently promoted the expression of MMP7, a kidney injury biomarker. Additionally, MMP7 inhibitors were used to demonstrate that the secreted MMP7 degrades surface E-cadherin. This feedback inhibition mechanism downregulated surface E-cadherin expression and inhibited the colonization of Leptospira. The degradation of surface E-cadherin activated the NF-κB signal transduction pathway. Leptospirosis-associated acute kidney injury is associated with the secretion of NGAL, a downstream upregulated biomarker of the NF-κB signal transduction pathway. A working model was proposed to illustrate the crosstalk between E-cadherin/ß-catenin and NF-κB signal transduction pathways during Leptospira infection. Thus, rLRR20 of Leptospira induces kidney injury in host cells and inhibits the adhesion and invasion of Leptospira through the upregulation of MMP7 and NGAL.

Enhanced early immune response of leptospiral outer membrane protein LipL32 stimulated by narrow band mid-infrared exposure.

Previous studies revealed significant impact on cancer cell by mid-infrared (MIR) radiation. However, the effects of narrow band MIR on immune reaction and infectious disease are still unknown. In this study, an enhanced innate immune response was observed through the interaction between Leptospiral outer membrane protein (LipL32) and toll-like receptor 2 (TLR2). Thereafter, human kidney proximal tubular cells (HK-2 cells) initiated a serial reaction of enhanced MCP-1 production. The 6 µm narrow bandwidth light source emitted by waveguide thermal emitter (WTE) was applied to induce carbonyl group (CO bond) stretching vibration during the stage of antigen-receptor complex formation. The amount of MCP-1 gene expression had 2.5 folds increase after narrow band MIR illumination comparing to non-MIR illumination at low dose LipL32 condition. Besides, both ELISA and confocal microscopy results also revealed that the chemokine concentration increased significantly after narrow band MIR illumination either at low or high concentration of LipL32. Furthermore, a specific phenomenon that narrow band MIR can amplify the signal of weak immune response by enhancing sensitivity of the interaction between antigen and receptor was observed. This study exhibits clear evidence that the narrow band MIR exposure can modulate the early immune response of infectious disease and play a potential role to develop host-directed therapy in the future.

The impact of primary location and age at orchiopexy on testicular atrophy for congenital undescended testis.

In this study, we investigated post-orchiopexy testicular growth of undescended testes (UDTs) at different primary locations and determined the risk factors for testicular atrophy (TA). We conducted a retrospective chart review of boys who had undergone orchiopexy for UDTs during January 2001-December 2013. Patient profile, age at operation, primary UDT location, and testicular volume were noted. TA was defined as ≥50% loss of volume after orchiopexy. The primary endpoints were testicular growth and TA after orchiopexy. The secondary endpoint was risk factors for TA. In total, 182 boys had undergone regular ultrasonography; the median follow-up period was 34 months. Among 230 UDTs, 18 (7.8%) atrophic testicles were identified within a median interval of 13 months after orchiopexy. TA rates were 3.3% (1/30), 6.9% (12/173), and 18.5% (5/27) in primary suprascrotal, canalicular, and above-inguinal UDTs, respectively. The survival probability of UDT was 91%, 92% and 100% when orchiopexy was performed in age ≤1 year, 1 < age ≤2 years, and 100% in age >2 years, respectively. Multivariate analysis revealed that inguinal and above-inguinal UDTs (hazard ratio [HR] 11.76, 95% confidence interval [CI] 1.55-89.33, p = 0.017) and genetic or endocrine disorders (HR 3.19, 95% CI 1.19-8.56, p = 0.021) were the risk factors for TA, but not age at operation, premature birth, and laterality. Thus, TA incidence was higher when patients had high primary testicular locations. Early orchiopexy before two years of age may be associated with higher TA risk, while most testicles have promising growth after orchiopexy.

Trifecta outcome of ureteral reconstruction in iatrogenic injury and non-iatrogenic ureteral lesions: a 10-year experience at a tertiary referral center.

PURPOSE: To analyze the trifecta outcome (functional, anatomical, and surgical aspects) of surgical reconstruction for ureteral lesions and investigate the factors affecting the success rate of such reconstruction. METHODS: We retrospectively reviewed the data of patients who underwent ureteral reconstruction at our institute between March 2007 and November 2016. Patient profiles, surgical methods, complications, ureteral stenting, laboratory data, and image studies were collected. The trifecta outcome was defined as preserved renal function, no progression of hydronephrosis, and no long-term stenting. The primary endpoint was the percentage of patients who achieved the trifecta outcome. The secondary endpoint was risk factors for trifecta outcome failure. RESULTS: We retrospectively reviewed 178 adult patients who had undergone ureteral reconstruction. The median follow-up period was 37.4 months. In total, 70 (39.3%) patients had iatrogenic ureteral injuries and 108 (60.7%) patients had non-iatrogenic ureteral lesions. Overall, 70% of the patients achieved the trifecta outcome after ureteral reconstruction. A multivariate analysis revealed that risk factors for trifecta failure were malignant diseases [odds ratio (OR) 2.93, p = 0.005], a history of pelvic radiation (OR 3.08, p = 0.032), preoperative estimated glomerular filtration rate < 60 (OR 2.52, p = 0.039), and a type of reconstruction ureteroureterostomy (OR 2.99, p = 0.014). CONCLUSIONS: Trifecta outcome could be used to evaluate the ureteral reconstruction in iatrogenic injury and non-iatrogenic ureteral lesions. This study revealed several risk factors that affected the trifecta outcome.

Advantage of early orchiopexy for undescended testis: Analysis of testicular growth percentage ratio in patients with unilateral undescended testicle.

This study reports the experience of our tertiary referral center and proposes a new indicator, the growth percentage ratio (GPR), for determining the optimal timing of surgical intervention. A retrospective review of boys who underwent orchiopexy for undescended testis from 2001 to 2013 was conducted. We analyzed testicular volumes in different age groups using the UDT to normally descended testis ratio and testicular GPR. A total of 134 boys with unilateral undescended testicle underwent regular ultrasonography follow-up examinations for more than a mean of 3.9 years. Forty-five (33.4%) of them underwent orchiopexy before the age of one year. Orchiopexy at this age resulted in a GPR (2.02 ± 0.40) that was significantly higher than the GPRs in the second (1 < age ≤ 2 years, 1.25 ± 0.13, p = 0.004) and third (age > 2 years, 1.24 ± 0.14 p = 0.008) age groups. The undescended testicle grew faster when orchiopexy was performed before one year of age. Orchiopexy performed within one year from birth significantly accelerates the growth of the UDT, as determined using the GPR, compared to other age groups. The present clinical evidence indicates that orchiopexy should be performed before one year of age.

A nanobiosensing method based on force measurement of antibody-antigen interaction for direct detection of enterovirus 71 by the chemically modified atomic force microscopic probe.

Hand, Foot and mouth disease (HFMD) is a common disease with high infectivity for children, and enterovirus 71 (EV71) is one of the main pathogens to cause the type of illness. Therefore, the aim of this study was to propose a rapid and effective technique for detecting EV71 directly based on the mechanism of biological intermolecular force by using atomic force microscopy (AFM). At first, we coated EV71 particles on the mica surface and made the EV71 antibodies (anti-EV71) fixed on the AFM tip by means of several chemical procedures. Then, AFM chemically modified tip was applied to measure the unbinding forces between EV71 and anti-EV71 by contact mode. Finally, by using AFM imaging calculating software, the EV71 particle size (mean±SD) was 31.36±3.87 nm (n = 200) and this result was concordance with previous literature. Besides, the force (mean±SD) between EV71 antigen and antibody complex was 336.9±64.7 pN. The force (mean±SD) between anti-EV71 and non-specific specimens was 47.1±15.1 pN and was significantly smaller (P < 0.05). Apparently, the results show that we can precisely identify EV71 infection among the samples by measuring the force magnitude and observing the occurrence of EV71/anti-EV71 unbinding events. Therefore, the combination of AFM system and the chemically modified tip has the potential to be a rapid and effective method for detecting EV71 directly.

Dynamic response of HPV16/anti-HPV16 pairs with unbinding events studied by atomic force microscopy.

This paper proposes an effective approach to distinguish whether samples include Human Papilloma virus type-16 (HPV16) by Atomic force microscopy (AFM). AFM is an important instrument in nanobiotechnology field. At first we identified the HPV16 by Polymerase chain reaction (PCR) analysis and Western blotting from specimen of the HPV patient (E12) and the normal (C2), and then we used an AFM to observe the surface ultrastructure by tapping mode and to measure the unbinding force between HPV16 coupled to an AFM tip and anti-HPV16 L1 coated on the substrate surface by contact mode. The experimental results by tapping mode show that the size of a single HPV viron was similar to its SEM image from the previous literatures; moreover, based on the purposed methods and the analysis, two obvious findings that we can determine whether or not the subject is a HPV patient can be derived from the results; one is based on the distribution of unbinding forces, and the other is based on the distribution of the stiffness. Furthermore, the proposed method could be a useful technique for further investigating the potential role among subtypes of HPVs in the oncogenesis of human cervical cancer.