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Strategies to design multifunctional interfaces for biosensors have been extensively investigated to acquire optimal sensitivity, specificity, and accuracy. However, heterogeneous ingredients in clinical samples inevitably generate background signals, exposing challenges in biosensor performance. Polymer coating has been recognized as a crucial method to functionalize biointerfaces by providing tailored properties that are essential for interacting with biological systems. Herein, we introduce for the first time two oligomeric silatranes, MPS-MPC n and MPS-PEGMACOOH m , which were copolymerized from mercaptopropylsilatrane (MPS) with either zwitterionic monomer 2-methacryloyloxyethyl phosphorylcholine (MPC) or carboxylated poly(ethylene glycol) methacrylate (PEGMACOOH) through thiol-ene polymerization. These oligomeric silatranes were prepared individually and in combinations in acidic and nonacid solvents for deposition on silicon wafers. Afterward, coating properties, including wettability, thickness, and elemental composition, were characterized by contact angle meter, ellipsometer, and X-ray photoelectron spectroscopy (XPS), respectively. Importantly, MPS-MPC n polymers were found to form thin films with high hydrophilicity and superior fouling repulsion to bacteria and protein, while mixed coating involving 70% MPS-PEGMACOOH 2.5 and 30% MPS-MPC 2.5 exhibited thinnest coating with best wettability among COOH-terminated coatings. Furthermore, the functional COOH group in the coated surfaces was exploited for postmodification with biological molecules via intermediated N -hydroxysuccinimide (NHS) ester group by amine coupling chemistry. Once again, the combination of 70% MPS-PEGMACOOH 2.5 and 30% MPS-MPC 2.5 provided an ultimate reduction in nonspecific adsorption (NSA) and established a finest signal discrimination through enzyme-linked immunosorbent assay. Consequently, these novel mixed oligomeric silatranes offer a promising approach for the construction of biosensor interfaces with dual functions in both nonspecific binding prevention and conjugation of biomolecules.

Vietnamese ginseng (Panax vietnamensis Ha & Grushv.) represents one of the famous Panax spp. for valuable applications in both traditional and modern medicine; in which, its rhizome part has mainly been used as the medicinal materials based on the bioactive ginsenosides such as ginsenoside Rb1, ginsenoside Rg1, ginsenoside Rd, and majonoside R2. In modern medicine, the development of medicinal materials and utilization of medicinal plants are crucially based on standard bioactive ingredients, so this study to evaluate the leaves of Vietnamese ginseng as source of bioactive ginsenoside led to the identification of seven ginsenosides (1-7). Of them, ginsenoside Rd (2) and pseudoginsenoside RS1 (5) showed inhibitory effects on acetylcholinesterase in vitro with the IC 50 values of 47.13 and 79.58 μM and supported by molecular docking analysis, in which ginsenoside Rd (2) and pseudoginsenoside RS1 (5) could play as allosteric inhibitors with high binding affinity (-8.5 and -9.4 kcal/mol) as evidenced by hydrogen bonding and hydrophobic interactions. The findings provided the scientific evidence for using the leaves of Vietnamese ginseng as an alternative source to the roots to enhance memory in traditional medicine as well as for further research on the anti-dementia effects of 2 and 5., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Many herbal species in the genus Ligustrum have been shown to contain compounds with anti-cancer biological activity. This study aimed to isolate some compounds from the leaves of Ligustrum robustum (Roxb.) Blume (L. robustum) and evaluate their effects against liver cancer cells. As a result, seven previously reported compounds (1-7) were isolated, including four lignans (1-4) and three phenolic derivatives (5-7). The structures of these compounds were determined using spectroscopic methods and comparison with reported data. All isolates were assessed for their inhibitory effects on HepG2 liver cancer cells. Screening results revealed that two compounds, isocubein (3) and 4-(2-acetoxyethyl)phenol (7), exhibited strong inhibitory activity against cell proliferation, with IC 50 values of 3.1±0.9 and 4.5±14 μM, respectively. Further analyses demonstrated that both compounds could suppress the formation and development of 3D tumorspheres in terms of quantity and size. Additionally, isocubein (3) and 4-(2-acetoxyethyl)phenol (7) exhibited the ability to inhibit the migration of HepG2 cells. This study represents the first report on the inhibitory activity against HepG2 liver cancer cells of extracts and isolated compounds from L. robustum, providing valuable information for future research aiming to develop products for liver cancer treatment., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Prolonging hot carrier cooling, a crucial factor in optoelectronic applications, including hot carrier photovoltaics, presents a significant challenge. High-energy band-nesting excitons within parallel bands offer a promising and underexplored avenue for addressing this issue. Here, we exploit an exceptional D exciton cooling prolongation of 2 to 3 orders of magnitude compared to sub-picosecond in typical transition metal dichalcogenides (TMDs) owing to the complex Coulomb environment and the sequential and mismatch-valley relaxation. Simultaneously, the intervalley scattering upconversion of band-edge excitons with the slow D exciton formation in the metastable Γ valley/hill also reduces the cooling rate. We successfully extract D and C excitons as hot carriers through integrating with various thicknesses of TiO x , achieving the highest efficiency of 98% and 85% at a Ti thickness of 2 nm. Our findings highlight the potential of band-nesting excitons for extending hot carrier cooling time, paving the way for advancements in hot carrier-based optoelectronic devices.

As the role of exosomes in physiological and pathological processes has been properly perceived, harvesting them and their internal components is critical for subsequent applications. This study is a debut of intermittent lysis, which has been integrated into a simple and easy-to-operate procedure on a single paper-based device to extract exosomal nucleic acid biomarkers for downstream analysis. Exosomes from biological samples were captured by anti-CD63-modified papers before being intermittently lysed by high-temperature, short-time treatment with double-distilled water to release their internal components. Exosomal nucleic acids were finally adsorbed by sol-gel silica for downstream analysis. Empirical trials not only revealed that sporadically dropping 95 °C ddH 2 O onto the anti-CD63-modified papers every 5 min for 6 times optimized the exosomal nucleic acids extracted by the anti-CD63 paper but also verified that the whole deployed procedure is applicable for point-of-care testing (POCT) in low-resource areas and for both in vitro (culture media) and in vivo (plasma and chronic lesion) samples. Importantly, downstream analysis of exosomal miR-21 extracted by the paper-based procedure integrated with this novel technique discovered that the content of exosomal miR-21 in chronic lesions related to their stages and the levels of exosomal carcinoembryonic antigen originated from colorectal cancer cells correlated to their exosomal miR-21., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Background and Aim: We aimed to evaluate the application of Peptest, a novel technique to detect pepsin in the saliva, and identify its threshold level for the diagnosis of gastroesophageal reflux disease (GERD) with extraesophageal symptoms., Methods: A cross-sectional study was conducted in two groups: patients with extraesophageal GERD symptoms (symptomatic group divided into GERD and non-GERD groups according to 24-h esophageal pH-impedance monitoring [pH-I] results) and healthy controls. For the symptomatic group, endoscopy, pH 24 h, high-resolution manometry (HRM), and salivary Peptest were performed. For the healthy control group, only Peptest was done. The accuracy of Peptest was compared with that of pH-I by the Lyon consensus criteria., Results: Chronic laryngitis was the most frequent extraesophageal symptom. On saliva testing, the GERD group had a higher prevalence of positive samples and pepsin concentration than the control group. Between GERD and non-GERD groups, the optimal threshold level was 31.2 ng/mL, with a sensitivity of 86.7% and specificity of 27.5%. The optimal threshold level was 31.4 ng/mL to differentiate GERD from healthy controls, with a sensitivity of 86.7% and specificity of 66.0%. Age, number of total refluxes, DeMeester score, post-reflux swallow-induced peristaltic wave (PSPW) index, and mean nocturnal baseline impedence (MNBI) were associated with pepsin concentration. Regarding HRM metrics, there was no significant difference of pepsin concentration between low/normal upper esophageal sphincter (UES) resting pressure, low/normal lower esophageal sphincter (LES) resting pressure, low/normal 4-s integrated relaxation pressure (IRP4s), and hypomotility/normal motility., Conclusion: Patients with extraesophageal symptoms had a higher prevalence of positive Peptest. The optimum threshold level of 31.4 ng/mL had high sensitivity and moderate specificity to differentiate between patients with GERD and healthy controls., (© 2023 The Authors. JGH Open published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

(±)-Patulinervones A ( 1 ) and B ( 2 ), two diastereomers of spiro -lignans sharing an unprecedented dimethyl- spiro [furan-2,2'-furo[2,3- b ]furan] 5/5/5 tricyclic moiety were isolated from the leaves of Melicope patulinervia (Merr. & Chun) C.C. Huang. Their structures were established by extensive spectroscopic data and electronic circular dichroism (ECD) analyses. The racemates (±)- 1 and 2 and their enantiomers exhibited α -glucosidase inhibitory effect with IC 50 values range of 10.08 ± 1.24 - 25.58 ± 1.97 µM.

Vietnamese ginseng (Panax vietnamensis Ha and Grushv., Araliaceae) is indigenous in the central highlands of Vietnam and the southernmost distribution in the Panax genus. Like other ginseng, Vietnamese ginseng is well known has been used as a tonic and for management of certain diseases in the traditional medicine. Nevertheless, it is noteworthy that in respect to the long history in use and systematic studied on Korean ginseng (P. ginseng), American ginseng (P. quinquefolius), Japanese ginseng (P. japonicus), and Chinese ginseng (P. notoginseng), the up-to-date published database on Vietnamese ginseng is relatively much less extensive. In our ongoing research on the promising Vietnamese medicinal plants, the present phytochemical investigation of the ethanol extract of the leaves of Panax vietnamensis led to the isolation of three compounds (1-3), including a new indole alkaloid N-glycoside (1) and two known compounds. Their structures were elucidated based on extensive physiochemical and chemical methods, especially the interpretation of NMR and MS spectra. The absolute configuration of 1 was determined based on the comparison of its experimental and theoretical ECD spectra along with NMR calculation. Compound 1 is naturally isolated N-glycoside, which is rarely found in natural products. The isolated compounds showed weak or no inhibitory activity against acetylcholinesterase enzyme (AChE)., (© 2023. The Author(s) under exclusive licence to The Japanese Society of Pharmacognosy.)

Organosilicons are prevalent for the development of nanostructures, adhesives, fillers, and surface functionalization due to their ease of operation, availability, and effective modification on various surfaces. 3-(Trimethoxysilyl) propyl methacrylate (TMSPMA) is a widely used commercial silane for designing hybrid polymers via radical polymerization for a wide spectrum of applications. However, the chemical stability and processibility of TMSPMA encounter burdens due to its susceptibility to hydrolysis and aggregation, resulting in limiting its functionality and implementations. In this work, methylacrylate silatrane (MAST) was newly developed to bear a chemically stable tricyclic caged silatranyl ring and a transannular N → Si dative bond for excellent stability, processability, and progressive deposition. A complete, uniform, and thin assembled adlayer of MAST on a silicon wafer was verified by a contact angle goniometer, ellipsometry, atomic force microscopy, X-ray photoelectron microscopy, and Fourier transform infrared spectroscopy. The good homogeneity and molecular orientation of the MAST coatings are attributed to controlled silanization on oxide surfaces and strong intermolecular hydrogen bonds between internal urea groups. Moreover, the zwitterionic monomer of 2-methacryloyloxyethyl phosphorylcholine (MPC) was employed to copolymerize with MAST or TMSPMA to afford macromolecular modifiers of p(MPC 9 - co -MAST 1 ) and p(MPC 9 - co -TMSPMA 1 ), respectively, for surface modification and antifouling properties on silicon substrates. p(MPC 9 - co -MAST 1 ) well preserved the reactivity of the silatrane groups after the polymerization process, whereas the hydrolysis of silane groups of p(MPC 9 - co -TMSPMA 1 ) obviously occurred, giving rise to aggregation of polymer chains. Therefore, the p(MPC 9 - co -MAST 1 ) film on surfaces exhibited superior wettability, grafting density, and antifouling properties compared to p(MPC 9 - co -TMSPMA 1 ). Accordingly, we envision the great potential of the MAST building block for the development of functional hybrid polymers, well-defined polymeric thin films, and nanomaterials.

Emerging evidence has shown that microRNAs play pivotal roles in wound healing. MicroRNA-21 (miR-21) was previously found to upregulate in order to fulfill an anti-inflammation role for wounds. Exosomal miRNAs have been identified and explored as essential markers for diagnostic medicine. However, the role of exosomal miR-21 in wounds has yet to be well studied. In order to facilitate the early management of poorly healing wounds, we developed an easy-to-use, rapid, paper-based microfluidic-exosomal miR-21 extraction device to determine wound prognosis in a timely manner. We isolated and then quantitatively examined exosomal miR-21 in wound fluids from normal tissues and acute and chronic wounds. Eight improving wounds displayed lower levels of exosomal miR-21 expression after wound debridement. However, four instances of increased exosomal miR-21 expression levels were notably associated with patients with poor healing wounds despite aggressive wound debridement, indicating a predictive role of tissue exosomal miR-21 for wound outcome. Paper-based nucleic acid extraction device provides a rapid and user-friendly approach for evaluating exosomal miR-21 in wound fluids as a means of monitoring wounds. Our data suggest that tissue exosomal miR-21 is a reliable marker for determining current wound status.

Residue concentrations of heavy metals, including As, Cd, Cr, Cu, Ni, Pb, and Zn, were determined in bottom ash, fly ash, and particulate matter (PM 10 ) samples collected from five municipal incinerators in northern Vietnam to assess their occurrence, distribution characteristics, and potential risks. Concentrations and profiles of heavy metals are presented, showing the dominance of Zn in all types of samples. Highly volatile elements (Cd, Pb, and Zn) were found at elevated proportions in PM 10 but not fly ash. The large difference in the heavy metal profiles could be explained by the variation of input raw materials, the absence of an appropriate cycle for the material feeding process, and post-combustion technology applied. Mass balance of heavy metals in the bottom ash, fly ash, and PM 10 varied significantly between the investigated incinerators, largely due to the difference in incineration technology and air pollution control system. Emission factors and annual emissions were also estimated, indicating the highest value and amount in bottom ash, followed by PM 10 and fly ash. Our results are among the first studies reporting contents and emissions of toxic elements in incinerated solid wastes in Vietnam., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: Cervical length (CL) measured by ultrasound in the second trimester is a predictor of spontaneous preterm birth (sPTB). The uterocervical angle (UCA) has recently been suggested as a predictor to identify women at risk of sPTB. The aim of this study was to investigate the UCAs' distribution in singleton pregnant women at 16 + 0 - 23 + 6 weeks of gestation with low risk for sPTB., Methods: This was a prospective cohort study of 1,051 pregnant women with singleton pregnancies at low risk for preterm delivery. Pregnant women with a viable singleton fetus at 16 + 0 - 23 + 6 weeks of gestation were enrolled in the study conducted at the Haiphong Hospital of Obstetrics and Gynecology, Vietnam, from 09/2019 to 09/2020. CL and the UCA were assessed using transvaginal ultrasonography (TVS) by a single sonographer. Subjects were followed-up until the end of pregnancy, and maternal and neonatal outcomes were recorded. The UCAs' range and their relationship with gestational age were evaluated using regression analysis. P < 0.05 was considered statistically significant., Results: The normal range of the UCA (5 th - 95 th percentiles) was 46.47° (95% CI, 40.27°-51.81°) to 127.06° (95% CI, 123.02° - 130.71°). The UCAs in the preterm birth (< 37 weeks) and full-term groups were 117.86° ± 20.25° and 83.80° ± 24.18°, respectively (p < 0.001). Linear regression analysis showed a significant change in the UCA range from 16 + 0 to 23 + 6 weeks of gestation (2.51 degrees per week, p < 0.001). The linear function yielded the highest correlation coefficient in the variation rule of the UCA values (r = 0.22). A total of 42/63 (66.7%) patients with preterm birth < 37 weeks had a UCA above the 75 th percentile. The majority of women with preterm birth had a UCA ≥ 95° compared with those with full-term delivery (88.9% vs. 31.3%, p < 0.001)., Conclusions: The results of this study present background information about the normal range of UCA values in singleton pregnant women at 16 + 0 to 23 + 6 weeks at low risk for sPTB in this Vietnamese cohort. In this study population at low risk for sPTB, pregnant women with a UCA value ≥ 95 o were also considered at risk for preterm birth., (© 2023. The Author(s).)

In nanobiotechnology, the importance of controlling interactions between biological molecules and surfaces is paramount. In recent years, many devices based on nanostructured silicon materials have been presented, such as nanopores and nanochannels. However, there is still a clear lack of simple, reliable, and efficient protocols for preventing and controlling biomolecule adsorption in such structures. In this work, we show a simple method for passivation or selective biofunctionalization of silica, without the need for polymerization reactions or vapor-phase deposition. The surface is simply exposed stepwise to three different chemicals over the course of ∼1 h. First, the use of aminopropylsilatrane is used to create a monolayer of amines, yielding more uniform layers than conventional silanization protocols. Second, a cross-linker layer and click chemistry are used to make the surface reactive toward thiols. In the third step, thick and dense poly(ethylene glycol) brushes are prepared by a grafting-to approach. The modified surfaces are shown to be superior to existing options for silica modification, exhibiting ultralow fouling (a few ng/cm 2 ) after exposure to crude serum. In addition, by including a fraction of biotinylated polymer end groups, the surface can be functionalized further. We show that avidin can be detected label-free from a serum solution with a selectivity (compared to nonspecific binding) of more than 98% without the need for a reference channel. Furthermore, we show that our method can passivate the interior of 150 nm × 100 nm nanochannels in silica, showing complete elimination of adsorption of a sticky fluorescent protein. Additionally, our method is shown to be compatible with modifications of solid-state nanopores in 20 nm thin silicon nitride membranes and reduces the noise in the ion current. We consider these findings highly important for the broad field of nanobiotechnology, and we believe that our method will be very useful for a great variety of surface-based sensors and analytical devices.

In this study, the Fresnel lens was investigated as a potential candidate for vision correction in patients with myopia. A few previous studies have suggested this idea; however, Fresnel lenses are limited by their aesthetics and quality. Therefore, we designed a combination of Fresnel lens grooves with a constant height and pitch of 13 µm and 0.1 mm, respectively, to overcome the limitations caused by ultra-precision machining with a tool nose radius of 30 µm. A thin replicated Fresnel lens with a power of -5 diopter was procured and applied directly as spectacles that are unattached to the normal lens. The optical performance and image quality of the Fresnel lens were compared with those of a conventional lens possessing the same power in both near and far vision. These results extend the applicability for the use of Fresnel lenses as vision-correcting ophthalmological lenses and imaging systems.

In this study, selective Nb doping ( P -type) at the WS 2 layer in a WS 2 -MoS 2 lateral heterostructure via a chemical vapor deposition (CVD) method using a solution-phase precursor containing W, Mo, and Nb atoms is proposed. The different chemical activity reactivity (MoO 3 > WO 3 > Nb 2 O 5 ) enable the separation of the growth temperature of intrinsic MoS 2 to 700 °C (first grown inner layer) and Nb-doped WS 2 to 800 °C (second grown outer layer). By controlling the Nb/(W+Nb) molar ratio in the solution precursor, the hole carrier density in the p -type WS 2 layer is selectively controlled from approximately 1.87 × 10 7 /cm 2 at 1.5 at.% Nb to approximately 1.16 × 10 13 /cm 2 at 8.1 at.% Nb, while the electron carrier density in n -type MoS 2 shows negligible change with variation of the Nb molar ratio. As a result, the electrical behavior of the WS 2 -MoS 2 heterostructure transforms from the N-N junction (0 at.% Nb) to the P-N junction (4.5 at.% Nb) and the P-N tunnel junction (8.1 at.% Nb). The band-to-band tunneling at the P-N tunnel junction (8.1 at.% Nb) is eliminated by applying negative gate bias, resulting in a maximum rectification ratio (10 5 ) and a minimum channel resistance (10 8 Ω). With this optimized photodiode (8.1 at.% Nb at V g = -30 V), an I photo / I dark ratio of 6000 and a detectivity of 1.1 × 10 14 Jones are achieved, which are approximately 20 and 3 times higher, respectively, than the previously reported highest values for CVD-grown transition-metal dichalcogenide P-N junctions.

Semiconductor-containing porous materials with a well-defined structure could be unique scaffolds for carrying out selective organic transformations driven by visible light. We herein introduce for the first time a heterostructure of silver indium sulfide (AgInS 2 ) ternary chalcogenide and a highly porous MIL-101(Cr) metal-organic framework (MOF) synthesised from polyethylene terephthalate plastic waste. Our results demonstrate that AgInS 2 nanoparticles were uniformly attached to each lattice plane of the octahedral MIL-101(Cr) structure, resulting in a nanocomposite with a high distribution of semiconductors in a porous media. We also demonstrate that the nanocomposite with up to 40% of AgInS 2 doping exhibited excellent catalytic activity for tetracycline degradation under visible light irradiation (∼99% tetracycline degraded after 4 h) and predominantly maintained its performance after five cycles. These results could promote a new material circularity pathway to develop new semiconductors that can be used to protect water from further pollution., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Time-domain backprojection algorithms are widely used in state-of-the-art synthetic aperture radar (SAR) imaging systems that are designed for applications where motion error compensation is required. These algorithms include an interpolation procedure, under which an unknown SAR range-compressed data parameter is estimated based on complex-valued SAR data samples and backprojected into a defined image plane. However, the phase of complex-valued SAR parameters estimated based on existing interpolators does not contain correct information about the range distance between the SAR imaging system and the given point of space in a defined image plane, which affects the quality of reconstructed SAR scenes. Thus, a phase-control procedure is required. This paper introduces extensions of existing linear, cubic, and sinc interpolation algorithms to interpolate complex-valued SAR data, where the phase of the interpolated SAR data value is controlled through the assigned a priori known range time that is needed for a signal to reach the given point of the defined image plane and return back. The efficiency of the extended algorithms is tested at the Nyquist rate on simulated and real data at THz frequencies and compared with existing algorithms. In comparison to the widely used nearest-neighbor interpolation algorithm, the proposed extended algorithms are beneficial from the lower computational complexity perspective, which is directly related to the offering of smaller memory requirements for SAR image reconstruction at THz frequencies.

Covid-19 lockdowns have improved the ambient air quality across the world via reduced air pollutant levels. This article aims to investigate the effect of the partial lockdown on the main ambient air pollutants and their elemental concentrations bound to PM 2.5 in Hanoi. In addition to the PM 2.5 samples collected at three urban sites in Hanoi, the daily PM 2.5 , NO 2 , O 3 , and SO 2 levels were collected from the automatic ambient air quality monitoring station at Nguyen Van Cu street to analyze the pollution level before (March 10th-March 31st) and during the partial lockdown (April 1st-April 22nd) with "current" data obtained in 2020 and "historical" data obtained in 2014, 2016, and 2017. The results showed that NO 2 , PM 2.5 , O 3 , and SO 2 concentrations obtained from the automatic ambient air quality monitoring station were reduced by 75.8, 55.9, 21.4, and 60.7%, respectively, compared with historical data. Besides, the concentration of PM 2.5 at sampling sites declined by 41.8% during the partial lockdown. Furthermore, there was a drastic negative relationship between the boundary layer height (BLH) and the daily mean PM 2.5 in Hanoi. The concentrations of Cd, Se, As, Sr, Ba, Cu, Mn, Pb, K, Zn, Ca, Al, and Mg during the partial lockdown were lower than those before the partial lockdown. The results of enrichment factor (EF) values and principal component analysis (PCA) concluded that trace elements in PM 2.5 before the partial lockdown were more affected by industrial activities than those during the partial lockdown., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Exosomes, nanovesicles derived from cells, contain a variety of biomolecules that can be considered biomarkers for disease diagnosis, including microRNAs (miRNAs). Given knowledge and demand, inexpensive, robust, and easy-to-use tools that are compatible with downstream nucleic acid detection should be developed to replace traditional methodologies for point-of-care testing (POCT) applications. This study deploys a paper-based extraction kit for exosome and exosomal miRNA analytical system with some quantifying methods to serve as an easy sample preparation for a possible POCT process. Exosomes concentrated from HCT116 cell cultures were arrested on paper-based immunoaffinity devices, which were produced by immobilizing anti-CD63 antibodies on Whatman filter paper, before being subjected to paper-based silica devices for nucleic acids to be trapped by silica nanoparticles adsorbed onto Whatman filter paper. Concentrations of captured exosomes were quantified by enzyme-linked immunosorbent assay (ELISA), demonstrating that paper-based immunoaffinity devices succeeded in capturing and determining exosome levels from cells cultured in both neutral and acidic microenvironments, whereas microRNA 21 (miR-21), a biomarker for various types of cancers and among the nucleic acids absorbed onto the silica devices, was determined by reverse transcription quantitative polymerase chain reaction (RT-qPCR) to prove that paper-based silica devices were capable of trapping exosomal nucleic acids. The developed paper-based kit and the devised procedure was successfully exploited to isolate exosomes and exosomal nucleic acids from different biological samples (platelet-poor plasma and lesion fluid) as clinical applications., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Lai, Lee, Vu, Vu, Tsai, Chen and Cheng.)

Objective: Familial transmission can possibly influence the infection and treatment of Helicobacter pylori. This study aimed to describe the prevalence of H. pylori infection and outcomes of eradication treatment among Vietnamese patients who live in the same households., Methods: We conducted a prospective cohort study of Vietnamese household members with upper gastrointestinal complaints. Participants received esophagogastroduodenoscopy and H. pylori testing. The H. pylori-positive patients were treated and asked to return for follow-up within 4 months. To explore factors associated with H. pylori infection at baseline, we performed multilevel logistic regression to account for the clustering effect of living in the same households. To explore factors associated with eradication failure, we used Poisson regression with robust variance estimation to estimate the risk ratio., Results: The prevalence of H. pylori infection was 83.5% and highest among children <12 years old (92.2%) in 1,272 patients from 482 households. There were variations in H. pylori infection across households (intraclass correlation = 0.14, 95% confidence interval (CI) 0.05, 0.33). Children aged <12 years had higher odds of H. pylori infection (odds ratio = 3.41, 95%CI 2.11, 5.50). At follow-up, H. pylori was eradicated in 264 of 341 patients (77.4%). The risk of eradication failure was lower for the sequential regimen with tetracycline., Conclusion: H. pylori infection was common among people living in the same households. Eradication success for H. pylori was higher for the tetracycline sequential regimen. More research should be focused on how family factors influence H. pylori infection and on eradication treatment., Competing Interests: The authors have declared that no competing interests exist.

This study aims to resolve the trade-off between the constraints and capabilities of ultra-precision machining to achieve ophthalmic Fresnel lenses. A general Fresnel lens pattern has a narrow variable pitch and curved grooves. However, we obviate the limitations of the tool nose radius constraint and the long tool path via ultra-precision machining of the modified Fresnel lens, ensuring a constant pitch of 0.1 mm and varying the height of straight grooves from 0 to 11 µm. Photorealistic raytracing visualization and MTF simulation verified the compatibility of the lens pattern with human perception sensitivity. Copper-coated mold was fabricated using a diamond tool with a tool nose radius of 5 µm. The replicated flexible Fresnel lens demonstrated a relative MTF imaging performance of 89.1% and was attached to the goggles for the qualitative assessment. The proposed Fresnel lens design and fabrication approach can be extended to applications in the visual and infrared ranges as well.

van der Waals heterostructures (vdWHs) of metallic (m-) and semiconducting (s-) transition-metal dichalcogenides (TMDs) exhibit an ideal metal/semiconductor (M/S) contact in a field-effect transistor. However, in the current two-step chemical vapor deposition process, the synthesis of m-TMD on pregrown s-TMD contaminates the van der Waals (vdW) interface and hinders the doping of s-TMD. Here, NbSe 2 /Nb-doped-WSe 2 metal-doped-semiconductor (M/d-S) vdWHs are created via a one-step synthesis approach using a niobium molar ratio-controlled solution-phase precursor. The one-step growth approach synthesizes Nb-doped WSe 2 with a controllable doping concentration and metal/doped-semiconductor vdWHs. The hole carrier concentration can be precisely controlled by controlling the Nb/(W + Nb) molar ratio in the precursor solution from ∼3 × 10 11 /cm 2 at Nb-0% to ∼1.38 × 10 12 /cm 2 at Nb-60%; correspondingly, the contact resistance R C value decreases from 10 888.78 at Nb-0% to 70.60 kΩ.μm at Nb-60%. The Schottky barrier height measurement in the Arrhenius plots of ln( I sat / T 2 ) versus q / K B T demonstrated an ohmic contact in the NbSe 2 /W x Nb 1- x Se 2 vdWHs. Combining p-doping in WSe 2 and M/d-S vdWHs, the mobility (27.24 cm 2 V -1 s -1 ) and on/off ratio (2.2 × 10 7 ) are increased 1238 and 4400 times, respectively, compared to that using the Cr/pure-WSe 2 contact (0.022 cm 2 V -1 s -1 and 5 × 10 3 , respectively). Together, the R C value using the NbSe 2 contact shows 2.46 kΩ.μm, which is ∼29 times lower than that of using a metal contact. This method is expected to guide the synthesis of various M/d-S vdWHs and applications in future high-performance integrated circuits.

Six new oligomeric neolignans including two trimeric neolignans (1 and 2) and four dimeric neolignans (3-6) were isolated from the leaves of Magnolia officinalis var. biloba. Their structures were determined based on HR-ESIMS and NMR data, as well as electronic circular dichroism (ECD) calculations. Compound 1 is formed from two obovatol moieties directly linked to an aromatic ring of the remaining obovatol moiety, which is an unprecedented type of linkage between monomers. All isolates were assessed for their inhibitory effects on NO production in LPS-stimulated RAW 264.7 macrophage cells. Compounds 1 and 3 showed significantly inhibitory activities with IC 50 values of 6.04 and 3.26 μmol·L -1 , respectively., (Copyright © 2021 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.)

Four new lignans, patulinones A-D (1-4) and three new acetophenone derivatives, patulinones E-G (5-7) were isolated from the leaves of Melicope patulinervia. Their structures were elucidated on the basis of the interpretation of HR-ESIMS, NMR, CD data. All the isolated compounds were evaluated for α-glucosidase inhibitory activity. Of the isolates, compound 4 was found to exhibit the strongest inhibition against α-glucosidase with IC 50 value of 6.02 ± 0.46 μM., (Copyright © 2020. Published by Elsevier B.V.)

(±)-Patulignans A-C (1-3), three unique pairs of lignan enantiomers were isolated from the leaves of Melicope patulinervia. Patulignan A (1) possesses an unprecedented dimethyloxonane moiety in nature, meanwhile patulignans B (2) and C (3) are epimers carrying a novel dimethyl-1,6-dioxaspiro[4.5]decane skeleton. Their structures were established by spectroscopy methods and electronic circular dichroism (ECD) calculations. Compounds 1-3 showed significant inhibitory activity against α-glucosidase.

Six new obovatol trimeric neolignans, houpulignans A-F (1-6) were isolated from the leaves of Magnolia officinalis var. biloba. Their structures were determined on the basis of the interpretation of HRESIMS, NMR data, and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 are the first examples of neolignans derived from three units of obovatol bearing a rare 1,4-benzodioxepane moiety. Compound 3 possesses a benzodihydropyran ring, meanwhile three units of obovatol in 4-6 are connected by an alkyl chain. Compounds 1-3 inhibited NO production in LPS-stimulated RAW264.7 cells with IC 50 values of 8.01, 20.21, and 4.05 µM, respectively., Competing Interests: Declaration of Competing Interest The authors declared that there is no conflict of interest., (Copyright © 2020. Published by Elsevier Inc.)

(±)-Melipatulinones A-C ( 1 - 3 ), three unique enantiomeric pairs of lignan-phloroglucinol hybrids along with the biogenetically related compound melipatulignan A ( 4 ), were isolated from the leaves of Melicope patulinervia . Melipatulinones A ( 1 ) and B ( 2 ) share a novel spiro[hydrobenzofuran-2,3'-furan] 5/5/6 tricyclic ring system, while melipatulinone C ( 3 ) features an unprecedented spiro[cyclopenta[ b ]hydrofuran-2,3'-furan] 5/5/5 tricyclic framework. Their structures were determined by spectroscopic methods, electronic circular dichroism (ECD) calculations, and X-ray diffraction. Compounds 1 - 3 exhibited a pancreatic lipase inhibitory effect.

Vehicle rollover is a very serious problem when considering the safety of heavy vehicles, which can result in large financial and environmental consequences. This paper investigates the interest of a Linear Parameter Varying (LPV) controller for an active anti-roll bar system of single unit heavy vehicles, in order to enhance roll stability. We propose a parameter dependent H ∞ / L P V controller with weighting functions, scheduled by the forward velocity (the varying parameter of the vehicle LPV model) and by the normalized load transfers at the two axles (part of the parameter dependent weighting functions) providing an on-line performance adaptation to the vehicle rollover risk. The effectiveness of the proposed controller is validated by using the TruckSim® simulation software with two different types of heavy vehicle: a fully loaded bus and a truck. The simulation results, in the frequency and time domains, show that the proposed strategy drastically improves the vehicle roll stability when compared with a H ∞ / L T I controller, a fixed weighting functions H ∞ / L P V controller and a passive anti-roll bar system.

The aim of this study was to evaluate the antibacterial activity against Streptococcus mutans and fibroblast viability of zirconia coated with glass ceramic powder containing Ag and F nanoparticles. Specimens were divided into eight groups depending on the glass ceramic powders: 5, 10, 15, 20 wt% of NaF and Ag, respectively. Adhesion of Streptococcus mutans on glass-coated zirconia surface was evaluated by antimicrobial test. Fibroblast viability was examined by WST-8 assay. In result, the bacterial activity was reduced by 11.8%, 15.4% in Ag 10 wt% and 20 wt% groups. When 5~15 wt% of NaF was added, bacterial counts decreased to 4.2~65.4%, and when 20 wt% of NaF was added, the number of bacteria increased by 29.4%. Regardless of Ag and NaF content, all zirconia specimens showed cell viability above 70%. Within the limitations of this study, zirconia coated with glass ceramics powder containing Ag and NaF was found to reduce the adhesion of Streptococcus mutans but had no influence on osteoblast activation.

This study evaluated the shear bond strength of zirconia to titanium implant components using silica-based glasses and compared the strength with that of implant components bonded using a commercial resin cement. Forty cylindrical zirconia specimens and forty titanium disks (Grade IV) were divided equally into four groups, depending on the adhesive used: three different types of glasses (group G, group GI, group GIB) and a self-adhesive resin cement (group U200), which was used as a control. The shear bond strength was evaluated using a universal testing machine and failure mode was examined by optical microscope. Data was analyzed using One-way ANOVA with p -value <0.05, which was considered statistically significant. The shear bond strength of the three glass groups was significantly higher than that of group U200 ( p <0.05). Failure mode in all groups was a combination of adhesive and cohesive modes. Shear bond strength of zirconia to titanium bonded using glasses was higher than that using self-adhesive resin cement.

Few interventions train homeless consumers in housing-related independent living skills. To inform the development of such interventions for the Department of Veterans Affairs' Supported Housing consumers with serious mental illness, we examined these consumers' problem-solving skills and deficits. We performed semistructured interviews and cognitive tests with 20 consumers who retained housing for ≥1 year ("stayers") and 20 consumers who lost housing in <1 year ("exiters"). Salient types of problems were identified in the qualitative data; we categorized problem-solving approaches by complexity level and identified differences in problem-solving complexity by consumers' housing outcomes. Instrumental (e.g., money management), interpersonal, and health-related problems were prominent in consumers' narratives. Cognition was poor among stayers and exiters. Problem-solving approaches were highly relevant to day-to-day functioning in supported housing. There was a trend toward greater problem-solving complexity in stayers versus exiters. These data explore potential challenges faced in supported housing and help inform the development of a Veterans Affairs-based housing-focused skills training intervention. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Saphenous vein (SV) is a common graft being used in coronary artery bypass grafting (CABG). Conventional (CON), intermediate (I), and no-touch (NT) are the most common harvesting techniques of SV for CABG. The aim of this study is to systematically review the NT versus CON and I techniques in harvesting SV for CABG. Twelve databases were searched for randomized controlled trials comparing the CON, I, and NT techniques in harvesting SV for CABG. Twelve reports of six RCTs were included. Our meta-analysis showed that with NT technique, patency rate was significantly higher when compared to I technique up to 18-month follow-up duration. In contrast, this significant difference was not maintained in terms of minor complications of leg wounds with both techniques. The NT has significantly higher patency rate compared to I vein harvesting technique. However, more RCTs are warranted to confirm these results.

A new phloroglucinol derivative, named eucalyptin B (1), along with five related known compounds (2 - 6), was isolated from the fruits of Eucalyptus globulus. Their structures were elucidated by means of 1D- and 2D-NMR spectroscopy, with the absolute configuration of 1 determined by electronic circular dichroism (ECD) calculations. All isolated compounds (1 - 6) were evaluated for their cytotoxic activities against lung (A549), breast (4T1), and skin (B16F10) cancer cell lines. On the basis of cell viability assay, the cytotoxic activity of eucalyptin B (1) was further confirmed by apoptosis assay. Additionally, after treatment with eucalyptin B (1), the apoptosis factor proteins (Bcl2 and Bax) and caspase-3 levels in A549 cells were also determined by Western-blot analysis. By cytotoxic assay, eucalyptin B (1) exhibited potent cytotoxicity against A549 cells with an IC 50 value of 1.51 μm and induced concentration dependent apoptosis of up to 49%. Additionally, eucalyptin B (1) inhibited 5-fold and increased 10-folds in the level of Bcl2 and Bax, respectively. Furthermore, the 11-fold increase in the level of caspase-3 confirmed eucalyptin B (1) activated caspase dependent apoptosis pathway. In conclusion, the isolated compound eucalyptin B (1) has promising cytotoxic activity in tumor cells, especially in A549., (© 2018 Wiley-VHCA AG, Zurich, Switzerland.)

Flowers of the hop plant provide both bitterness and "hoppy" flavor to beer. Hops are, however, both a water and energy intensive crop and vary considerably in essential oil content, making it challenging to achieve a consistent hoppy taste in beer. Here, we report that brewer's yeast can be engineered to biosynthesize aromatic monoterpene molecules that impart hoppy flavor to beer by incorporating recombinant DNA derived from yeast, mint, and basil. Whereas metabolic engineering of biosynthetic pathways is commonly enlisted to maximize product titers, tuning expression of pathway enzymes to affect target production levels of multiple commercially important metabolites without major collateral metabolic changes represents a unique challenge. By applying state-of-the-art engineering techniques and a framework to guide iterative improvement, strains are generated with target performance characteristics. Beers produced using these strains are perceived as hoppier than traditionally hopped beers by a sensory panel in a double-blind tasting.

This study evaluated the effect of acid etching on surface characteristics, flexural strength and osteoblast cell response of glass-infiltrated zirconia. Zirconia specimens were divided into six groups: untreated zirconia (Z); glass-infiltrated zirconia (ZG); glass-infiltrated and sandblasted zirconia (ZGS); glass-infiltrated, sandblasted and 5 min acid-etched zirconia (ZGS-E5); glassinfiltrated, sandblasted and 15 min acid-etched zirconia (ZGS-E15); glass-infiltrated, sandblasted and 25 min acid-etched zirconia (ZGS-E25). Surface roughness, biaxial flexural strength and MC3T3-E1 cell proliferation were evaluated. When increasing etching time, surface roughness significantly increased while flexural strength decreased. Cell proliferation rate at day 3 on group ZGS-E15 and ZGS-E25 was significantly higher than that of other groups. Surface roughness and flexural strength of glass-infiltrated zirconia can be controlled by adjusting etching time. Rough surface made by acid etching following glass infiltration significantly enhanced osteoblast cell response. Glass infiltration improved strength of zirconia but severe acid etching slightly reduced strength of zirconia.

This study investigated the mechanical properties and initial cell response of bioactive glass infiltrated zirconia before and after sandblasting. One hundred zirconia specimens were divided into the following four groups: untreated zirconia (ZR), sandblasted zirconia (ZS), glass infiltrated zirconia (ZG), and sandblasted glass infiltrated zirconia (ZGS). Surface roughness, biaxial flexural strength, hardness and osteoblast cells proliferation were evaluated. ZGS group showed a slight decrease in hardness. However it has improvement in flexural strength (686.2 MPa). After sandblasting, the ZGS group had the highest surface roughness (R a = 1.24 μm) with enhanced osteoblast cells response. Our results indicated that sandblasting method can improve the mechanical properties of bioactive glass infiltrated zirconia with better osteoblast cell response. This new surface is promising for zirconia dental implant application in the future.

The purpose of this study was to examine the surface characteristics of bioactive glass-infiltrated zirconia specimens that underwent different hydrofluoric acid (HF) etching conditions. Specimens were classified into the following six groups: Zirconia, Zirliner, Porcelain, Bioactive glass A1, Bioactive glass A2, and Bioactive glass A3. Zirliner and porcelain were applied to fully sintered zirconia followed by heat treatment. Bioactive glass was infiltrated into presintered zirconia using a spin coating method followed by complete sintering. All the specimens were acid-etched with 10% or 20% HF, and surface roughness was measured using a profiler. The surface roughness of the zirconia group was not affected by the etching time or the concentration of the acid. The roughness of the three bioactive glass groups (A1, A2, and A3) was slightly increased up until 10 minutes of etching. After 1 hour of etching, the roughness was considerably increased. The infiltrated bioactive glass and acid etching did not affect the adhesion and proliferation of osteoblasts. This study confirmed that surface roughness was affected by the infiltration material, etching time, and acid concentration. For implant surfaces, it is expected that the use of etched bioactive glass-infiltrated zirconia with micro-topographies will be similar to that of machined or sand-blasted/acid-etched (SLA) titanium.

Purpose: The purpose of this study was to evaluate the influence of acid etching treatment on surface characteristics and biological response of glass-infiltrated zirconia., Materials and Methods: A hundred zirconia specimens were divided into four groups depending on surface treatments: untreated zirconia (group Z); acid-etched zirconia (group ZE); glass-infiltrated zirconia (group ZG); and glass-infiltrated and acid-etched zirconia (group ZGE). Surface roughness, surface topography, surface morphology, and Vickers hardness of specimens were evaluated. For biological response test, MC3T3-E1 cell attachment and proliferation on surface of the specimens were examined. The data were statistically analyzed using one-way ANOVA and Tukey's HSD test at a significance level of 0.05., Results: Group ZGE showed the highest surface roughness (Ra = 1.54 µm) compared with other groups ( P < .05). Meanwhile, the hardness of group Z was significantly higher than those of other groups ( P < .05). Cell attachment and cell proliferation were significantly higher in group ZGE ( P < .05)., Conclusion: We concluded that effective surface roughness on zirconia could be made by acid etching treatment after glass infiltration. This surface showed significantly enhanced osteoblast cell response.

This study investigated the effects of different mixing ratios of crop residues and biochar with liquid digestate from anaerobically treated pig manure on CH₄, CO₂, and N₂O emissions over 84 days in a system of passive aeration composting, resembling typical Vietnamese solid manure storage conditions. Two treatments with solid manure were included for comparison. The results showed that C losses through CH4 and CO₂emissions accounted for 0.06-0.28% and 1.9-26.7%, respectively, of initial total C. CH4 losses accounted for just 0.4-4.0% of total C losses. Total N losses accounted for 27.1-40% of initial total N in which N₂O emissions corresponded to 0.01-0.57% of initial total N, and hence accounted for only 0.1-1.8% of total N losses. It is assumed that the remainder was either the result of denitrification losses to N₂or ammonia volatilization. The composting of biochar (B) or crop residue with digestate (D) showed significantly lower CH4 and N₂O emissions compared with composting manure (M) (p < .05). The composting of digestate with biochar showed significantly lower CO₂and CH₄emissions and significantly higher N₂O emissions compared to the composting of digestate with rice straw (RS) (p < .05). The combined composting of digestate with biochar and rice straw (D + B + RS5:0.3:1) showed significantly reduced N₂O emissions compared with composting digestate with biochar with alone (p < .05). Composting sugar cane bagasse (SC) with digestate (D + SC) significantly reduced CH₄and N₂O emissions compared with the composting of rice straw with digestate (D + RS3.5:1 and D + RS5:1) (p < .05).

Modern pig production contributes to many environmental problems that relate to manure, especially in areas with highly intensive production systems and in regions like Asia where the regulative control is not effective. Therefore, the objective of this study was to use three different pig diets varying in dietary protein, fibre and fat as representative for Danish (DK), Thai (TH) and Vietnamese (VN) pig production to develop and evaluate different approaches to predict/calculate excretion from growing pigs in comparison with the experimentally determined values.Nine female growing pigs were used in a digestibility and balance experiment. Excretion of dry matter (DM), nitrogen (N), phosphorus (P) and carbon (C) of the experimental diets were determined.Due to the highest dietary fibre content, VN had the lowest digestibility of N, P and C (73, 49, and 73%, respectively) compared with the DK and TH pig diets. From the known diet composition using standard table values on chemical and nutrient digestibly, high accuracy (bias) and low variation was found and the results could be used for prediction on chemical composition and excretion in faeces and urine in growing pigs. Calculation based on standard values regarding nutrient retention in the pig body as used in the Danish manure normative system (DMNS) showed likewise to be quite useful for quantifying the total excretion of N and P.Overall, the results demonstrate that simple models that require cheap and normally available information on dietary nutrients can give useful information on nutrient excretion in growing pigs.

The goal of this research was to determine whether or not chickpea (Cicer arietinum L.), commonly known as Garbanzo beans, is a hyper accumulator for copper (Cu) in contaminated soils amended with EDTA. Statistical analysis (2 tailed Pearson Correlation) revealed significant correlations between: Translocation index and stem biomass (r = 0.859**; p < 0.01); Tolerance index and stem biomass (r = 0.762**; p < 0.01); and bioconcentration factor of stem/soil and soil Cu concentration (r = -0.545*; p < 0.05). Therefore, C. arietinum seems to be a cost-effective and environmentally friendly hyperaccumulator for Cu at 100 ppm Cu and 10 mM EDTA.

This study investigated the effects of meteorological conditions and spatial variations on the toxicity of polycyclic aromatic hydrocarbons (PAHs) in airborne PM(10) in Ulsan, the largest industrial city in Korea. Daily PM(10) samples were collected on quartz microfiber filters using high volume samplers located in a downtown area, a residential area and an industrial area of Ulsan during spring and summer sampling periods. Sixteen individual PAHs were extracted into a mixture solution of dichloromethane and n-hexane (1:1, v/v) in an ultrasonic bath and were analyzed using a high performance liquid chromatography system with an ultra-violet detector (HPLC-UVD). The average total PAH concentrations from the three representative sampling sites of Ulsan ranged from 16.15 to 57.12 ng/m(3) in spring and from 11.11 to 34.56 ng/m(3) in summer. The toxicity equivalent concentrations (TEQs) of the PAHs in PM(10) of Ulsan ranged from 1.82 to 13.1 ng/m(3), with an average level of 4.17 ng/m(3). The highest TEQs were found in the downtown area, which had an average value of 6.30 ng/m(3) in spring and 5.52 ng/m(3) in summer. BaP and DahA were identified as the major carcinogenic PAHs that contributed to 34.8 and 59.4% of the total carcinogenic potency of PAHs in PM(10) in Ulsan. The identified TEQs were highly correlated (r(2) = 0.73-0.90, p<0.01) with the total PAH concentrations for each area. The TEQs showed a significant correlation (p < 0.01) with the concentration of air pollutants, including PM(10), PM(2.5) and NO(2)., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Tumor hypoxia influences the outcome of treatment with radiotherapy, chemotherapy and even surgery, not only for the treatment of large bulky tumors with extensive necrosis, but also in the treatment of very small primary tumors and recurrences, micrometastases, and surgical margins with microscopic tumor involvement. Because hypoxic tumor cells are resistant to radiation and to many anticancer drugs, many approaches to circumventing the therapeutic resistance induced by hypoxia have been examined in laboratory studies and clinical trials. In this review, these approaches and the results of past laboratory and clinical studies are described and the limitations of the past agents and their testing are discussed. We describe the importance of new technologies for measuring hypoxia in human tumors, which allow assessment of pretreatment tumor oxygen levels and changes in hypoxia over the course of prolonged treatment regimens. These offer the possibility of improving the design of clinical trials and the selection of patients who will benefit from hypoxia-directed therapies, as well as the possibility of facilitating the development of better agents and regimens for use in hypoxia-directed therapy. We also discuss how the improved understanding of the abnormal vascular beds in solid tumors and of the effects of hypoxia and related microenvironmental insults, resulting from recent and ongoing research, offers the potential for finding new therapeutic targets, that may lead to the development of new agents and novel therapeutic approaches for selectively targeting cells in the adverse microenvironments within solid tumors.

A new structure for polarization-selective elements, consisting of two holographic gratings and a Dove prism coupler, is proposed. The absence of a multistage waveguide and the benefits of compact size and lightweight volume are the outstanding features of the new structure. Based on the coupled-wave theory, the analysis and design of the structure are discussed in detail to calculate the required index modulation. Several parameters, such as the recording intensity, the exposure time, and the recording angles for the fabrication of the proposed element, are determined. Under these conditions, the element is fabricated in Dupont photopolymer HRF-150-38 material and with an operating wavelength of 532 nm. A simplified pickup head is constructed to evaluate the performance of the fabricated element.

Naturally occurring and man-made (synthetic) fibers of respirable sizes are substances that have been identified by the U.S. Environmental Protection Agency (U.S. EPA) as priority substances for risk reduction and pollution prevention under the Toxic Substances Control Act (TSCA). The health concern for respirable fibers is based on the link of occupational asbestos exposure and environmental erionite fiber exposure to the development of chronic respiratory diseases, including interstitial lung fibrosis, lung cancer, and mesothelioma in humans. There is also considerable laboratory evidence indicating that a variety of fibers of varying physical and chemical characteristics can elicit fibrogenic and carcinogenic effects in animals under certain exposure conditions. This paper discusses key scientific issues and major default assumptions and uncertainties pertaining to the risk assessment of inhaled fibers. This is followed by a description of the types of assessment performed by the U.S. EPA to support risk management actions of new fibers and existing fibers under TSCA. The scope and depth of these risk assessments, however, vary greatly depending on whether the substance under review is an existing or a new fiber, the purpose of the assessment, the availability of data, time, and resources, and the intended nature of regulatory action. In general, these risk assessments are of considerable uncertainty because health hazard and human exposure information is often incomplete for most fibers. Furthermore, how fibers cause diseases and what specific determinants are critical to fiber-induced toxicity and carcinogenicity are still not completely understood. Further research to improve our knowledge base in fiber toxicology and additional toxicity and exposure data gathering are needed to more accurately characterize the health risks of inhaled fibers.

The current U.S. Environmental Protection Agency (EPA) and other national/international guidelines specify the use of two species and two sexes rodents (usually the rat and the mouse) for carcinogenicity testing of chemicals. In view of the enormous number of chemicals to be tested, the high cost of testing, and the large number of animals used in the present protocol, many academic, industrial, and government authorities are examining the possibility of using a reduced protocol (less than two species and two sexes of rodents) for carcinogenicity testing of chemicals. The use of a reduced protocol offers many advantages as well as some disadvantages. To pursue further the potential implications and impacts of using a reduced protocol for carcinogenicity testing on the processes of hazard identification and risk assessment, a workshop entitled "Evaluation of Reduced Protocols for Carcinogenicity Testing of Chemicals" was held at the Embassy Suites Hotel in Alexandria, Virginia on September 22 and 23, 1992. It was cosponsored by EPA's Office of Prevention, Pesticides and Toxic Substances (OPPTS) and the National Toxicology Program of the National Institutes of Environmental Health Sciences (NTP/NIEHS) and attended by more than 60 participants from government, industry, academia, and the general public. The Expert Consensus Panel and most of the participants supported the use of reduced protocols in carcinogenicity testing. However, it was recognized that reduced protocols may not be appropriate for the testing of all chemicals and that additional analyses/data may be needed for selection of the most appropriate reduced protocol for certain chemicals/chemical classes.

This article describes the effects of chronically administered phenobarbital (180 mg/day p.o.) in dogs on the bioavailability of single 40-mg oral doses of propranolol and on the pharmacokinetics and the patterns of propranolol metabolism in urine after both oral (40 mg) and i.v. (6 mg) doses. Phenobarbital decreased the bioavailability of propranolol from 7.7 to 3.5%. By using a gas chromatography/mass spectrometry technique, the quantitative metabolic pattern of i.v. propranolol was unaltered by phenobarbital, but increases in hydroxylation and induction of new metabolites were observed for oral propranolol after phenobarbital treatment. Chronic phenobarbital treatment led to significant decreases in the half-lives of propranolol after both i.v. and oral doses. Little change was observed in the hepatic blood flow, systemic clearance or intrinsic oral clearance. These data demonstrate the completely nonrestrictive elimination of propranolol. With phenobarbital, both the extent of plasma protein binding and the distribution into erythrocytes change significantly, yet the overall clearance remains unaltered. The half-lives fell in responses to the binding-induced reduction in the apparent volume of distribution.

In HeLa S3 cells, sodium butyrate was found to potentiate the cytotoxicity of chloroethylnitrosoureas and alkylating agents in vitro. Using a soft-agar colony-forming assay, 2.5 and 5.0 mM sodium butyrate pretreatment for 22 h increased the cell killing efficacy of both methyl- and chloroethylnitrosoureas by between 30 and 70%. The potentiation of cytotoxicity of bifunctional nitrogen mustards by butyrate was less than that of nitrosoureas, with a 15-30% increased cell kill at 5 mM butyrate. Sodium butyrate per se reduced plating efficiency and caused growth delay if residual levels (calculated at 100 microM for starting concentrations of 5 mM) were not removed by washing prior to plating.

By use of an XAD-2 sample purification procedure, the quantitative patterns of the in vitro metabolism of propranolol and four of its metabolites have been examined by a GC/MS/DATA procedure. Supernatant fractions (10,000g) from both dog and rat livers have been used to degrade propranolol, 4-hydroxypropranolol, N-deisopropylpropranolol, propranolol glycol, and alpha-naphthoxylactic acid. There were both qualitative and quantitative differences in dog and rat metabolism; rat 10,000g supernatant fraction produced more hydroxylation than that of the dog. alpha-Naphthol is not produced from propranolol directly, but rather from alpha-naphthoxylactic acid with an intermediate step requiring NAD+ as a cofactor. We observed no degradation of 4-hydroxypropranolol from the 10,000g supernatant preparations. Thus, 1,4-naphthalenediol is more likely a product of 4-hydroxypropranolol glycol.