Geosmin and 2-MIB are responsible for the majority of earthy and musty events related to the drinking water. These two odorants have extremely low odor threshold concentrations at ng L−1 level in the water, so a simple and sensitive method for the analysis of such trace levels was developed by headspace solid-phase microextraction coupled to gas chromatography/mass spectrometry. In this study, the orthogonal experiment design L32 (49) was applied to arrange and optimize experimental conditions. The optimum was the following: temperatures of extraction and desorption, 65°C and 260°C, respectively; times of extraction and desorption, 30 min and 5 min, respectively; ionic strength, 25% (w/v); rotate-speed, 600 rpm; solution pH, 5.0. Under the optimized conditions, limits of detection (S/N = 3)
were 0.04 and 0.13 ng L−1 for geosmin and 2-MIB, respectively. Calculated calibration curves gave high levels of linearity with a correlation coefficient value of 0.9999 for them. Finally, the proposed method was applied to water samples, which were previously analyzed and confirmed to be free of target analytes. Besides, the proposal method was applied to test environmental water samples. The RSDs were 2.75%~3.80% and 4.35%~7.6% for geosmin and 2-MIB, respectively, and the recoveries were 91%~107% and 91%~104% for geosmin and 2-MIB, respectively.
Objective: To investigate the effect of hyperbaric oxygen therapy (HBOT) on the iNOS mRNA-iNOS-NO signaling pathway and neurofunction protected in a rat spinal cord injury model. Methods: A total of 36 Sprague-Dawley rats were randomly divided into 3 groups: control group (n=12), SCI group (n=12) and SCI + HBOT group (n=12). SCI + HBOT group In the SCI group and SCI + HBOT groups, SCI was performed on rats. In the SCI + HBOT group, rats with SCI underwent HBO treatment 30 min after SCI for 24 sessions. After HBO therapy, measurement of motor evoked potential (MEP), Basso, Beattie, Bresnahan (BBB) scoring and pathological examination were done. RT-PCR and immunohistochemistry were employed to detect the mRNA and protein expression of iNOS, respectively. Diazo colorimetry was performed to detect the serum NO content. Results: The mRNA and protein expression of iNOS in the spinal cord and the serum NO content were markedly increased in the SCI group as compared to the control group (P<0.05). However, the mRNA and protein expression of iNOS and the serum NO content were dramatically reduced in the SCI + HBOT group as compared to the SCI group (P<0.05). Conclusion: HBO therapy can promote the neuroprotection following SCI, which may be related to the effect of HBO on the iNOS mRNA-iNOS-NO signaling pathway.
Hyperbaric oxygen; spinal cord injury; rat; nitric oxide; inducible nitric oxide synthase
Understanding the linkages between ecosystem services (ES) and human well-being (HWB) is crucial to sustain the flow of ES for HWB. The Millennium Ecosystem Assessment (MA) provided a state-of-the-art synthesis of such knowledge. However, due to the complexity of the linkages between ES and HWB, there are still many knowledge gaps, and in particular a lack of quantitative indicators and integrated models based on the MA framework. To fill some of these research needs, we developed a quantitative index system to measure HWB, and assessed the impacts of an external driver – the 2008 Wenchuan Earthquake – on HWB. Our results suggest that our proposed index system of HWB is well-designed, valid and could be useful for better understanding the linkages between ES and HWB. The earthquake significantly affected households' well-being in our demonstration sites. Such impacts differed across space and across the five dimensions of the sub-index (i.e., the basic material for good life, security, health, good social relations, and freedom of choice and action). Since the conceptual framework is based on the generalizable MA framework, our methods should also be applicable to other study areas.
The aim of this study was to explore the clinical value of the porcine acellular dermal xenograft (ADX) in combination with autologous split-thickness skin and pure autologous split-thickness skin grafting applied in deep full-thickness burns and scar wounds. A total of 30 patients with deep burns were randomly divided into experimental and control groups following escharectomy. The patients were separately treated with porcine acellular dermal xenograft (ADX) in combination with autologous split-thickness skin and pure autologous split-thickness skin graft. The wound healing was observed routinely and the scores were evaluated using Vancouver scar scale at different times following transplant surgery. The samples of cograft regions and the control group (pure transplant split-thickness skin autograft) were observed using light microscopy and electron microscopy, and the follow-up results were recorded. No conspicuous rejections on the cograft wound surface were observed. Compared with the control group, the cograft wounds were smooth, presented no scar contracture and exhibited good skin elasticity and recovery of the joint function. The cografted skin combined well and displayed a clear and continuous basal membrane, as well as gradually combined skin structure, a mature stratum corneum, downward extended rete pegs, a mainly uniform dermal collagen fiber structure, regular alignment, and fewer blood capillaries. Clear desmosome cograft regions were identified among heckle cells, as well as a clear and continuous basal membrane. The cografted skin of the combined split-thickness autograft and the acellular heterologous (porcine) dermal matrix showed an improved shape and functional recovery compared with the pure split-thickness skin autograft. The combination of the meshed ADX and the split-thickness skin autograft applied in deep full-thickness burns and scar wounds may induce tissue regeneration via dermis aiming. This method also has superior shape and functional recovery, and has an extensive clinical application value.
skin grafting; burns; slit-thickness skin; acellular dermal xenograft
Bone sialoprotein (BSP) has been implicated in a variety of physiological and pathophysiological events, including tumor cell invasion, bone homing, adhesion, and matrix degradation. To explore the potential involvement of BSP in human breast cancer cell invasion and metastasis, we used retrovirus-mediated RNAi to deplete BSP levels in the human bone-seeking breast cancer cell line MDA-MB-231BO (231BO) and established the 231BO-BSP27 and 231BO-BSP81 cell clones. Cell proliferation, colony formation, wound healing, and the ability to invade into matrigel of these BSP-depleted clones were all decreased. Both 231BO-BSP27 cells and 231BO-BSP81 cells showed a significant (15.4% and 28.6% respectively) reduction of bone metastatic potential following intracardiac injection as determined by X-ray detection and by hematoxylin and eosin staining. Moreover, the expression of integrins αvβ3 and β3 was decreased in the BSP-silenced cells whereas ectopic BSP expression increased the integrins αvβ3 and β3 levels. These results together suggest that BSP silencing decreased the integrin αvβ3 and β3 levels, in turn inhibiting cell migration and invasion and decreasing the ability of the cells to metastasize to bone.
Conservation investments are increasingly being implemented through payments for ecosystem services (PES) for the protection and restoration of ecosystem services around the world. Previous studies suggested that social norms have substantial impacts on environmental behaviors of humans, including enrollment of PES programs. However, it is still not well understood how social norms are affected by the design of PES programs and how the evolution of social norms may affect the efficiency of conservation investments. In this paper, we developed an agent-based simulation model to demonstrate the evolution and impacts of social norms on the enrollment of agricultural land in a PES program. We applied the model to land plots that have been enrolled in China’s Grain-to-Green Program (GTGP) to examine reenrollment in an alternative payment program when the current payments ceased. The study was conducted in Wolong Nature Reserve where several thousand plant and animal species, including giant pandas, may benefit from the reenrollment. We found that over 15% more GTGP land can be reenrolled at the same payment if social norms were leveraged by allowing more than ten rounds of interactions among landholders regarding their reenrollment decisions. With only three rounds of interactions, an additional 7.5% GTGP land was reenrolled at the same payment due to the effects of social norms. In addition, the effects of social norms were largest at intermediate payments and were smaller at much higher or much smaller payments. Even in circumstances where frequent interactions among landholders about their enrollment decisions are not feasible, policy arrangements that divide households into multiple waves for sequential enrollment can enroll over 11% more land at a given payment level. The approach presented in this paper can be used to improve the efficiency of existing PES programs and many other conservation investments worldwide.
agent-based model; conservation investments; Grain-to-Green Program; payments for ecosystem services; social norms
Nanofibers containing ferrocene (Fc) have been prepared for the first time by electrospinning. In this paper, Fc was dispersed uniformly throughout the poly(vinypyrrolidone) (PVP) matrix for the purpose of combining the properties of PVP and Fc. The effects of solvents and Fc concentration on the morphologies and diameters of nanofibers were investigated. In the DMF/ethanol solvent, the morphologies of the obtained nanofibers significantly changed with the increase of Fc concentration. The results demonstrated that the morphologies of the nanofibers could be controlled through adjusting solvents and Fc concentration. Scanning electron microscopy (SEM) showed that the diameters of the obtained composite fibers were about 30–200 nm at different Fc concentrations. Thermogravimetric analysis (TGA) results confirmed the presence of ferrocene within the PVP nanofibers. X-ray diffraction (XRD) results showed that the crystalline structure of Fc in the fibers was amorphous after the electrospinning process. A biological evaluation of the antimicrobial activity of Fc/PVP nanofibers was carried out by using Gram-negative Escherichia coli (E. coli) as model organisms. The nanofibers fabricated by this method showed obvious antibacterial activity. Electrochemical properties were characterized based on cyclic voltammetry measurements. The CV results showed redox peaks corresponding to the Fc+/Fc couple, which suggested that Fc molecules encapsulated inside PVP nanofibers retian their electrochemical activity. The properties and facile preparation method make the Fc/PVP nanofibers promising for antibacterial and sensing applications.
composites; electrochemistry; electrospinning; membranes; porous materials
Geometrical diffuse reflection is a common optical phenomenon that occurs when a reflecting surface has roughness of order of hundreds of micrometres. Light rays thus reflect uniformly in all directions with each ray obeying Snell's law. Of interest is knowing what happens when light reflects off surfaces with roughness of nanometres. Here, by introducing nanoscaled roughness on the hexagonal faces of ZnO nanocavities, we observe luminescent profiles with flowery patterns, replacing the usual whispering gallery modes. The unique profile for these nanocavities is attributed to wave diffuse reflection, which occurs when the features on the reflecting surfaces are typically nanometre-sized. Light with wavelengths of similar scale “sees” these nano-perturbations, and undergoes scattering rather than geometrical diffuse reflection. These findings could benefit the fields of nanoscale topography and nanoscopic uniform lighting by using wave diffuse reflection.
Fluorescence in situ hybridization (FISH) tests provide promising molecular imaging biomarkers to more accurately and reliably detect and diagnose cancers and genetic disorders. Since current manual FISH signal analysis is low-efficient and inconsistent, which limits its clinical utility, developing automated FISH image scanning systems and computer-aided detection (CAD) schemes has been attracting research interests. To acquire high-resolution FISH images in a multi-spectral scanning mode, a huge amount of image data with the stack of the multiple three-dimensional (3-D) image slices is generated from a single specimen. Automated preprocessing these scanned images to eliminate the non-useful and redundant data is important to make the automated FISH tests acceptable in clinical applications. In this study, a dual-detector fluorescence image scanning system was applied to scan four specimen slides with FISH-probed chromosome X. A CAD scheme was developed to detect analyzable interphase cells and map the multiple imaging slices recorded FISH-probed signals into the 2-D projection images. CAD scheme was then applied to each projection image to detect analyzable interphase cells using an adaptive multiple-threshold algorithm, identify FISH-probed signals using a top-hat transform, and compute the ratios between the normal and abnormal cells. To assess CAD performance, the FISH-probed signals were also independently visually detected by an observer. The Kappa coefficients for agreement between CAD and observer ranged from 0.69 to 1.0 in detecting/counting FISH signal spots in four testing samples. The study demonstrated the feasibility of automated FISH signal analysis applying a CAD scheme to the automated generated 2-D projection images.
Fluorescence in situ hybridization (FISH); Automated FISH signal analysis; Computer-aided detection (CAD); Molecular imaging biomarker
Mesenchymal stem cells (MSCs) are emerging as a promising therapeutic approach of cell-based therapy for a wide range of autoimmune disorders and degenerative diseases. In preclinical and clinical studies, MSCs have been shown to be highly efficient in treating graft-versus-host disease, systemic lupus erythematosus, multiple sclerosis, type 1 diabetes, myocardial infarction, liver cirrhosis, inflammatory bowel disease, and other disorders. The underlying therapeutic mechanisms of MSCs include their homing efficiency to the tissue injury sites, their differentiation potential, their capability to produce a large amount of trophic factors, and their immunomodulatory effect. Because tissue damage sites are complicated milieus with distinct types of inflammatory cells and factors, available data have demonstrated that the properties of MSCs could be fundamentally influenced by the inflammatory elements. Thus, an understanding of the interaction between MSCs and the inflammatory microenvironment will provide critical information in revealing the precise in vivo mechanisms of MSC-mediated therapeutic effects and designing more practical protocols for clinical use of these cells.
Mesenchymal stem cells; Immunosuppression; Cell-based therapy; Translational medicine
Aim. To analyze the clinicopathological features of meningioangiomatosis (MA) associated with meningioma. Methods. We present one case of MA associated with meningioma. Histopathological examination and immunohistochemistry were used. Results. The age of the patient was 33-year-old man. Histopathologically, MA was characterized by vascular proliferation with perivascular meningothelial cells and/or fibroblast proliferation, entrapped glial islands. In addition, MA was associated with transitional meningioma. The patient was alive without evidence of recurrence at 18 months after mass resection. Conclusion. MA associated with meningioma is an extremely rare lesion. The differential diagnosis includes cortical invasion by meningioma and intracerebral schwannoma. Patients with MA associated with meningioma often have a good prognosis after operation.
Objective. This study aimed to investigate improvements in inflammatory mediator levels in induced sputum and airway hyperresponsiveness (AHR) in cough variant asthma (CVA) during long-term inhaled corticosteroid (ICS) treatment. Patients and Methods. Patients with CVA (N = 35) and classic asthma (N = 26) and healthy subjects (N = 24) were recruited into this study. All patients were treated with budesonide (400 μg/day). Measurement of inflammatory mediators in induced sputum and PD20-FEV1 (the accumulated provocative dose resulting in a 20% decrease in FEV1) in histamine-challenged subjects was performed every three months after the start of medication. Interleukin- (IL-) 5 and IL-10 were assayed by ELISA, and the percentage of eosinophils was detected with Giemsa stain. Trends during the follow-up period were analyzed using a general linear model. Results. Inflammatory mediator levels in induced sputum and PD20-FEV1 in patients with CVA and classic asthma differed from those in the control group, although no differences were found in the two asthmatic groups. PD20-FEV1 significantly increased in CVA patients after ICS treatment for 3 months, while classic asthma patients exhibited a delayed change in AHR. After ICS treatment, levels of IL-5 and IL-10 as well as the percentage of eosinophils in the CVA group were altered at 3 months and 6 months, respectively. Accordingly, the level of inflammatory mediators in classic asthma changed more slowly. Conclusion. CVA has a greater improvement in airway inflammation and airway hyperresponsiveness (AHR) than classic asthma with respect to inhaled corticosteroid (ICS). Short-term ICS considerably reduces AHR although longer treatment is required for complete control of airway inflammation.
We report a facile method to prepare a nanoarchitectured lithium manganate/graphene (LMO/G) hybrid as a positive electrode for Li-ion batteries. The Mn2O3/graphene hybrid is synthesized by exfoliation of graphene sheets and deposition of Mn2O3 in a one-step electrochemical process, which is followed by lithiation in a molten salt reaction. There are several advantages of using the LMO/G as cathodes in Li-ion batteries: (1) the LMO/G electrode shows high specific capacities at high gravimetric current densities with excellent cycling stability, e.g., 84 mAh·g−1 during the 500th cycle at a discharge current density of 5625 mA·g−1 (~38.01 C capacity rating) in the voltage window of 3–4.5 V; (2) the LMO/G hybrid can buffer the Jahn–Teller effect, which depicts excellent Li storage properties at high current densities within a wider voltage window of 2–4.5 V, e.g., 93 mAh·g−1 during the 300th cycle at a discharge current density of 5625 mA·g−1 (~38.01 C). The wider operation voltage window can lead to increased theoretical capacity, e.g., 148 mAh·g−1 between 3 and 4.5 V and 296 mAh·g−1 between 2 and 4.5 V; (3) more importantly, it is found that the attachment of LMO onto graphene can help to reduce the dissolution of Mn2+ into the electrolyte, as indicated by the inductively coupled plasma (ICP) measurements, and which is mainly attributed to the large specific surface area of the graphene sheets.
cathode; graphene; Li-ion battery; lithium manganate
Delayed neutrophil apoptosis may be an important factor in the persistent inflammation associated with chronic obstructive pulmonary disease (COPD). Bcl-2 family proteins are important regulators of neutrophil apoptosis. We determined the mRNA levels of pro-apoptotic Bak and anti-aptototic Bcl-xl and Mcl-1 members of the Bcl-2 family in unstimulated peripheral blood neutrophils from patients with mild to moderate COPD and compared these to neutrophils from healthy controls.
Neutrophils were isolated from peripheral blood samples of 47 COPD patients (smokers: N = 24) and 47 healthy controls (smokers: N = 24). Percentages of apoptotic cells were determined at 4, 24, and 36 h for unstimulated neutrophils cultured in vitro. Neutrophil mRNA expression of Bak, Bcl-xl, and Mcl-1 was determined by real-time polymerase chain reaction (PCR). FEV1 (% predicted) and FVC were determined by spirometry and correlations between mRNA levels and lung function parameters were determined.
The percentages of apoptotic cells among unstimulated neutrophils from COPD patients were significantly lower compared to cells from controls after 4, 24, and 36 h in culture; smoking history had only a minimal effect on these differences. Unstimulated neutrophils from COPD patients had significantly lower Bak mRNA expression and higher expressions of Bcl-xl and Mcl-1 mRNA than cells from healthy controls. Again, smoking history had only a minimal effect on these trends. Bak mRNA expression was significantly positively correlated with both % predicted FEV1 and the FEV1/FVC ratio, while Bcl-xl and Mcl-1 mRNA expressions were significantly negatively correlated with %predicted FEV1 and the FEV1/FVC ratio.
The genes for pro-apoptotic Bak, and anti-apoptotic Bcl-xl and Mcl-1 may be important in regulating the delayed neutrophil apoptosis observed in COPD, which may contribute to COPD pathogenesis.
The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1605269445677066
Apoptosis; Bcl-2; Chronic obstructive pulmonary disease; Lung function; Neutrophils
Conservation policies are increasing in response to human-induced ecosystem degradation, but little is known about their interplay with natural disasters. Through an analysis of satellite imagery and field data we evaluated the impacts of a devastating earthquake on forest recovery and avoided forest loss estimated to have been obtained by two of the largest conservation programs in the world. Results show that more than 10% of the forests in Wenchuan County, Sichuan province, China were immediately affected by the 2008 earthquake, offsetting some gains in forest cover observed since the enactment of the conservation programs. But without the enactment of these conservation programs, the combined effects of human disturbance and earthquake-induced landslides could have severely reduced the region’s forest cover. The continuation—and enhancement—of incentives for participation in conservation programs will be important for reducing the environmental impacts of the combined effects of human disturbance and natural hazards not only in the study area but also in many disaster-prone regions around the world.
Conservation; Grain-to-Green Program; Natural disasters; Natural Forest Conservation Program; Payments for ecosystem services; Wenchuan Earthquake
The conventional optical microscope has been the primary tool in assisting pathological examinations. The modern digital pathology combines the power of microscopy, electronic detection, and computerized analysis. It enables cellular-, molecular-, and genetic-imaging at high efficiency and accuracy to facilitate clinical screening and diagnosis. This paper first reviews the fundamental concepts of microscopic imaging and introduces the technical features and associated clinical applications of optical microscopes, electron microscopes, scanning tunnel microscopes, and fluorescence microscopes. The interface of microscopy with digital image acquisition methods is discussed. The recent developments and future perspectives of contemporary microscopic imaging techniques such as three-dimensional and in vivo imaging are analyzed for their clinical potentials.
surface-enhanced Raman scattering; on-wire lithography; surface plasmon resonance; nanowire; surface chemistry
We report a simple and reproducible method for fabricating heterometallic nanogaps, which are made of two different metal nanorods separated by a nanometer-sized gap. The method is based upon on-wire lithography, which is a chemically enabled technique used to synthesize a wide variety of nanowire-based structures (e.g., nanogaps and disk arrays). This method can be used to fabricate pairs of metallic electrodes, which exhibit distinct work functions and are separated by gaps as small as 2 nm. Furthermore, we demonstrate that a symmetric thiol-terminated molecule can be assembled into such heterometallic nanogaps to form molecular transport junctions (MTJs) that exhibit molecular diode behavior. Theoretical calculations demonstrate that the coupling strength between gold and sulfur (Au-S) is 2.5 times stronger than that of Pt-S. In addition, the structures form Raman hot spots in the gap, allowing the spectroscopic characterization of the molecules that make up the MTJs.
The numerical and/or structural deviation of some chromosomes (i.e., monosomy and polysomy of chromosomes 3 and X) are routinely used as positive genetic biomarkers to diagnose cervical cancer and predict the disease progression. Among the available diagnostic methods to analyze the aneusomy of chromosomes 3 and X, fluorescence in situ hybridization (FISH) technology has demonstrated significant advantages in assisting clinicians to more accurately detect and diagnose cervical carcinoma at an early stage, in particular for the women at a high risk for progression of low-grade and high-grade squamous intra-epithelium lesions (LSIL and HSIL). In order to increase the diagnostic accuracy, consistency, and efficiency from that of manual FISH analysis, this study aims to develop and test an automated FISH analysis method that includes a two-stage scheme. In the first stage, an interactive multiple-threshold algorithm is utilized to segment potential interphase nuclei candidates distributed in different intensity levels and a rule-based classifier is implemented to identify analyzable interphase cells. In the second stage, FISH labeled biomarker spots of chromosomes 3 and X are segmented by a top-hat transform. The independent FISH spots are then detected by a knowledge-based classifier, which enables recognition of the splitting and stringy FISH signals. Finally, the ratio of abnormal interphase cells with numerical changes of chromosomes 3 and X is calculated to detect positive cases. The experimental results of four test cases showed high agreement of FISH analysis results between the automated scheme and the cytogeneticist’s analysis including 92.7% to 98.7% agreement in cell segmentation and 4.4% to 11.0% difference in cell classification. This preliminary study demonstrates that the feasibility of potentially applying the automatic FISH analysis method to expedite the screening and detecting cervical cancer at an early stage.
Fluorescence in situ hybridization (FISH); Automated FISH analysis; Cervical cancer; Computer-aided detection (CAD); Chromosomes 3 and X
Nasopharyngeal carcinoma (NPC), one of the most common cancers in population with Chinese or Asian progeny, poses a serious health problem for southern China. It is unfortunate that most NPC victims have had lymph node metastasis (LNM) when first diagnosed. We believe that the 2D based serum proteome analysis can be useful in discovering new biomarkers that may aid in the diagnosis and therapy of NPC patients. To filter the tumor specific antigen markers of NPC, sera from 42 healthy volunteers, 27 non-LNM NPC patients and 37 LNM NPC patients were selected for screening study using 2D combined with MS. Pretreatment strategy, including sonication, albumin and immunoglobulin G (IgG) depletion, was adopted for screening differentially expressed proteins of low abundance in serum. By 2D image analysis and MALDI-TOF-MS identification, twenty-three protein spots were differentially expressed. Three of them were further validated in the sera using enzyme-linked immunosorbent assay (ELISA). Our research demonstrates that HSP70, sICAM-1 and SAA, confirmed with ELISA at sera and immunohistochemistry, are potential NPC metastasis-specific serum biomarkers which may be of great underlying significance in clinical detection and management of NPC.
Nasopharyngeal carcinoma; Serum proteome; Carcinogenesis; Lymph node metastasis
heme protein cytochrome c adsorbed to a two-layer
gold surface modified with a self-assembled monolayer of 2-mercaptoethanol
was analyzed using a two-dimensional (2D) heterospectral correlation
analysis that combined surface-enhanced infrared absorption spectroscopy
(SEIRAS) and surface-enhanced Raman spectroscopy (SERS). Stepwise
increasing electric potentials were applied to alter the redox state
of the protein and to induce conformational changes within the protein
backbone. We demonstrate herein that 2D heterospectral correlation
analysis is a particularly suitable and useful technique for the study
of heme-containing proteins as the two spectroscopies address different
portions of the protein. Thus, by correlating SERS and SEIRAS data
in a 2D plot, we can obtain a deeper understanding of the conformational
changes occurring at the redox center and in the supporting protein
backbone during the electron transfer process. The correlation analyses
are complemented by molecular dynamics calculations to explore the