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1.
Water Res ; 207: 117810, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34741901

RESUMO

Urine with its abundant macronutrients (N-P-K) is an ideal resource for the production of fertiliser. However, the odor and pathogens in the raw urine must be removed to meet the public acceptance of urine collection systems and to enable its safe reuse as a fertiliser. In this work, real urine was collected and treated through a pilot-scale gravity-driven membrane bioreactor (GDMBR) to remove the malodorous organics and to nitrify almost 50% of the ammonia into nitrate. The stablised urine was subsequently distilled via low-cost heat localized solar evaporation (HLSE) to produce a non-odorous solid fertiliser. The developed HLSE with a small footprint can attract bulk solution into a vertical insulated space and quickly heat it up to 68 °C within 1 h. The HLSE process had vapour flux at 1.3 kg m-2 h-1 as well as high solar to vapour conversion efficiency at 87%. Based on the EDX mapping and XRD analysis, the generated crystals are mainly NaNO3, NH4Cl, NaCl, NH4H2PO4 and K2HPO4, which are ideal nutrients for vegetation. In this study, the produced urine-derived fertilisers have a better performance on the growth of the leafy basil than the all-purpose commercial fertilisers. Generally, the GDMBR-HLSE is a promising cost-effective and green technology for nutrients recovery from urine.

2.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(4): 365-370, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34374255

RESUMO

Objective: To study the effects of electroacupuncture on the expressions of autophagy-related factors LC3-Ⅱ, Beclin1, Atg7, and P62 in the liver of rapidly aging (senescence accelerated mouse/prone8,SAMP8) mice, and to explore the mechanisms of electroacupuncture to improve liver lipid metabolism in mice. Methods: Thirty-week-old male SAMP8 mice were randomly divided into model group, drug group, and electroacupuncture group, with 7 mice in each group. Seven anti-rapid aging SAMR1 mice of the same age were used as the control group. The animals in the control group and the model group were bred routinely for 2 weeks without any intervention; the drug group was treated with intraperitoneal injection of rapamycin at the dose of 10 mg·kg-1·d-1, once a day, 6 consecutive days a week; the electroacupuncture group was given "Shenshu" and "Taichong" Electroacupuncture at point(15 minutes a day, 6 consecutive days a week). The serum lipid metabolism and liver lipid deposition of mice were detected, the distribution of liver autophagy body, the protein and mRNA expressions of liver LC3 - Ⅱ, Beclin1, Atg7 and P62 were determined. Results: Compared with the control group, the total cholesterol (TC), triglycerides (TG), and low density lipoprotein (LDL) of the model group were increased significantly(P<0.01). In the model group, lipid droplet deposition was obvious, autophagosomes were decreased, the protein and mRNA expression levels of autophagy- related factors LC3-Ⅱ, Beclin1 and Atg7 were decreased significantly (P<0.01), while the protein and mRNA expressions of P62 were increased significantly (P<0.01). Compared with the model group, the serum contents of TG, TC, and LDL of the mice in the electroacupuncture group and the drug group were decreased significantly (P<0.01), lipid droplet deposition was reduced, autophagosomes were increased, the protein and mRNA expression levels of LC3 -Ⅱ, Beclin1 and Atg7 were increased significantly(P<0.01), and the protein and mRNA expression levels of P62 were decreased significantly(P<0.01). The protein and mRNA expression levels of Beclin1 and Atg7 in the liver of the electroacupuncture group were not significantly different from the drug group (P>0.05). Conclusion: Electroacupuncture can alleviate liver lipid metabolism disorders, which may be related to the regulation of the expressions of liver autophagy related factors LC3-Ⅱ, Beclin1, Atg7, and P62, thereby promoting liver autophagy in SAMP8 mice.


Assuntos
Eletroacupuntura , Envelhecimento , Animais , Autofagia , Metabolismo dos Lipídeos , Lipídeos , Fígado , Masculino , Camundongos
3.
Zhen Ci Yan Jiu ; 46(4): 259-65, 2021 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-33931988

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture(EA)on locomotor activity and the expression of high-mobility group box-1(HMGB1) and Toll-like receptor 4(TLR4) in mice with spinal cord injury(SCI), so as to explore its mechanisms underlying improvement of SCI at the acute stage. METHODS: Forty-eight female C57BL/6 mice were equally randomized into 3 groups: sham operation, model and EA. The SCI model was established by clamping the spinal cord with a serrefine after laminectomy at the 1st lumbar vertebra(L1). EA (1.5 Hz/7.5 Hz, 1.0 mA) was applied to "Jiaji"(EXH-B2) for 10 min, once a day for 5 and 14 days, separately. The hindlimb locomotor function was assessed by Basso, Beattie, Bresnahan Locomotor Rating Scale (BBB). Histopathological changes of the injured area of the spinal cord were determined by H.E. staining. The expression levels of spinal HMGB1, TLR4, ionized calcium binding adaptor molecule 1(Iba1) proteins were detected by Western blot, and the Iba1-positive microglial cells and HMGB1 and Iba1 co-labelled microglia were displayed by immunofluorescence staining. RESULTS: After SCI, the BBB scores on day 5 and 14 were obviously decreased (P<0.05), and the expression of HMGB1 on day 14, TLR4 on day 5 and 14, the number of Iba1-positive microglia as well as the co-expressed HMGB1/Iba1-positive microglia on day 5 and 14 were significantly increased in the model group relevant to the sham operation group (P<0.05, P<0.01). In the EA intervention group, SCI-induced reduction of BBB scores on day 5 and 14, and increases of the expression of HMGB1 and Iba1 on day 14, and TLR4 on day 5 and 14, and the number of Iba1-positive cells as well as the co-expressed HMGB1/Iba1-positive microglia on day 14 were reversed relevant to the model group (P<0.05,P<0.01). H.E. staining showed a structural disorder with lots of cavities, severe inflammatory infiltration with a large quantity of inflammatory cells, and a reduction of normal neurons in the injured spinal cord tissue in the model group, which was relatively milder, with lower activation of microglia in the EA group. CONCLUSION: EA can significantly improve locomotor function in SCI mice, which is associated with its effects in suppressing the expression of inflammatory factors such as HMGB1, TLR4, Iba1 and the over-activation of microglia.


Assuntos
Eletroacupuntura , Proteína HMGB1 , Traumatismos da Medula Espinal , Animais , Feminino , Proteína HMGB1/genética , Camundongos , Camundongos Endogâmicos C57BL , Medula Espinal , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/terapia , Coluna Vertebral , Receptor 4 Toll-Like/genética
4.
Zhen Ci Yan Jiu ; 46(1): 45-51, 2021 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-33559425

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Jiaji" (EX-B2) on the levels of autophagy and endoplasmic reticulum stress in mice with spinal cord injury (SCI), so as to explore its mechanism underlying improvement of SCI. METHODS: A total of 60 female C57BL/6 mice were randomly divided into sham operation, model and EA groups, which were further divided into 7 d and 14 d subgroups (10 mice in each subgroup). The SCI model was established by pressing the exposed spinal cord (L1) with a vascular clamp for 15 s. EA was applied to bilateral EX-B2 3 h after modeling, once a day for 7 and 14 d, respectively. Basso Mouse Scale(BMS) for locomotion was used to evaluate hindlimb motor function on day 7 and 14 after SCI. H.E. staining was used to observe histopathologic changes of the injured spinal cord tissue, and Western blot employed to detect the expression of glucose regulatory protein-78 (GRP78), Caspase-12, microtubule-associated protein light chain 3 II (LC-II) and P62(also known as sqstm1/Sequestome1) proteins. Immunofluorescence staining was used to detect the immunoacti-vities of spinal CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP, an endoplasmic reticulum stress-inducible protein) and P62. RESULTS: On the 7th and 14th day after SCI, the BMS scores and expression levels of LC3II protein were significantly down-regulated (P<0.05), and the expression levels of P62, GRP78 and Caspase-12 proteins, the immunoactivities of CHOP and P62 were all significantly up-regulated on both day 7 and 14 in the model group than in the sham operation group (P<0.05).Compared with the model group, the BMS scores and the expression levels of LC3II protein were significantly increased on both day 7 and 14 (P<0.05), while the expression levels of P62, GRP78 and Caspase-12 proteins, and the immunoactivities of CHOP and P62 were obviously decreased on day 7 and 14 in the EA group (P<0.05). Outcomes of H.E. stain showed that the cells with nuclei pyknosis and swelling and the necrotic cells appeared in the model group, which was relatively fewer in the EA group. CONCLUSION: EA of EX-B2 can improve the locomotor function in SCI mice, which may be related to its effects in up-regulating the expression of LC3II (to promote cell autophagy), and down-regulating the expression of P62, GRP78, Caspase-12 and CHOP proteins (to inhibit endoplasmic reticulum stress) in the spinal cord tissue.


Assuntos
Eletroacupuntura , Traumatismos da Medula Espinal , Animais , Autofagia/genética , Estresse do Retículo Endoplasmático/genética , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Medula Espinal , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/terapia
5.
Water Res ; 177: 115785, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32304906

RESUMO

In the present study, radiolabelled formate was used as a probe compound in order to gain mechanistic insight into the catalytic ozonation process using a commercially available iron oxide-impregnated activated carbon catalyst. We simultaneously analysed the adsorptive and oxidative removal of formate in order to determine the contribution of the catalyst to adsorption and oxidant generation processes respectively. Our results show that the presence of the catalyst enhanced ozone decay as well as the rate and extent of formate oxidation at pH 3.0 compared to that observed in the presence of ozone alone as a result of oxidant generation via O3-Fe oxide interaction. A reduction in rate and extent of formate oxidation on addition of t-butanol and Cl- (known hydroxyl radical (•OH) scavengers under acidic conditions) provides evidence that the oxidant generated during catalytic ozonation at pH 3.0 is •OH. Moreover, the oxidation of formate during catalytic ozonation mostly occurs at the solid-liquid interface and/or in bulk solution with adsorption playing no role in the overall oxidation process with this finding supported by the exceptionally high oxidation efficiency compared to the extent of adsorption observed when no O3 was added. While catalytic ozonation was effective in formate oxidation at pH 3.0, the presence of the catalyst did not lead to an increase in either the rate or extent of formate oxidation at pH 7.3 and 8.5 suggesting that only protonated iron oxide surface sites generate strong oxidant(s) on interaction with O3. Based on our understanding of the processes operating during the ozonation and catalytic ozonation processes, a mathematical model has been developed that adequately describes the experimental results obtained here. Overall, this study shows that systematic measurement of ozone decay, removal of the parent compound as well as formation of the oxidized products under well controlled conditions are required for unequivocal elucidation of the mechanism of catalytic ozonation.


Assuntos
Ozônio , Poluentes Químicos da Água , Purificação da Água , Catálise , Carvão Vegetal , Compostos Férricos
6.
Water Res ; 171: 115390, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31865129

RESUMO

The knowledge about membrane biofouling evolution in full-scale membrane bioreactor (MBR) applications is quite lacking, notwithstanding a few lab-scale investigations. For the first time, this study elaborated the effect of online NaOCl cleaning on the dynamic development of membrane biofilm microbiota during long-term operation of a large-scale MBR for municipal wastewater treatment (40,000 m3/d). Four times of membrane autopsies were conducted during 160 days operation to scrutinize the microbial community and concomitant organic foulants. The transmembrane pressure difference (TMP) development revealed limited effect of 30 min online NaOCl cleaning on long-term biofouling removal. NaOCl not only altered the structure of biofilm communities but also increased the richness and evenness on early fouling stages. Meanwhile, network analysis revealed the keystone taxa f_Comamonadaceae that played key roles in stabilizing community structure and developing anti-cleaning and irreversible fouling propensity of the biofilm. NaOCl cleaning also impacted the evolving of keystone taxa by intensifying the competition between the dominated taxa f_Moraxellaceae and other species during early fouling stages. Furthermore, the succession of the biofilm microbiota synchronously accelerated the TMP increase and the accumulation of organic foulants including polysaccharides, aromatic proteins and soluble microbial products during biofilm maturation. These identified key stubborn foulants shed light on limitations of current online NaOCl cleaning and provide guidance to optimize the efficiency of online chemical cleaning protocols in full-scale MBR operations.


Assuntos
Incrustação Biológica , Membranas Artificiais , Autopsia , Reatores Biológicos , Águas Residuárias
7.
Opt Express ; 27(26): 38541-38552, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878619

RESUMO

We propose an on-chip optical narrowband reflector (NBR) based on two cascaded Bragg gratings (BGs). A π phase shifted anti-symmetric Bragg grating (π-PS-ASBG) and a rear uniform Bragg grating (UBG), are in-line connected. The π-PS-ASBG provides a hybrid mode resonance between the even- and odd TE (TE0 and TE1) modes, while the UBG is used as a rear reflector to reflect the TE0 mode that transmitted from the π-PS-ASBG. Different from traditional UBG, the reflection bandwidth decreases when the coupling coefficient increases. The calculated 3-dB bandwidth is 0.16 nm when the whole grating length is 400 µm. The proposed NBR can be applied in the cases requiring narrow reflection such as narrow linewidth semiconductor lasers.

8.
Zhen Ci Yan Jiu ; 44(11): 781-6, 2019 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-31777225

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the expression of apolipoprotein E (ApoE) and related proteins of inflammation and anti-oxidative stress in spinal cord in mice with spinal cord injury (SCI), so as to explore its mechanisms underlying function repair. METHODS: Thirty-six female C57BL/6 mice were equally randomized into 3 groups: sham operation, model and EA. The SCI model was established by clamping the spinal cord for 25 s with a serrefine after laminectomy of the 1st lumbar vertebra (L1). EA (1.5 Hz/7.5 Hz, 1.0 mA) was applied to bila-teral "Zusanli" (ST36) and "Sanyinjiao" (SP6) for 10 min, once a day for 7 days. The hindlimb locomotor function was assessed according to the state of the range of motion, coordination, claw gesture of the hind leg ankle-joint, trunk stabi-lity and the tail posture by using Basso Mouse Scale(BMS). The histopathological changes of the injured area of the spinal cord were determined by H.E. staining. The expression levels of ApoE, phosphorylated nuclear transcription factor-κB(p-NF-κB), interleukin 1 beta(IL-1ß), phosphorylated extracellular regulatory protein kinase(p-ERK1/2), extracellular regulatory protein kinase(ERK1/2), nuclear factor erythroid 2-related factor 2(Nrf2) and heme oxidase-1(HO-1) in the spinal cord were detected by Western blot, and the glial fibrillary acidic protein (GFAP)-positive astrocytes were displayed by immunofluorescence staining. RESULTS: After modeling, the BMS scores were significantly decreased in the model group compared with the sham operation group (P<0.05). Following EA, the BMS scores were markedly increased in the EA group relevant to the model group (P<0.05), suggesting an improvement of the hindlimb locomotor function. H.E. stain showed structural disorder with lots of cavities, severe inflammatory infiltration with large quantity of inflammatory cells, and apparent reduction of normal neurons in the injured spinal cord tissue of model group, which was milder in the EA group. The expression levels of ApoE, p-NF-κB, IL-1ß, p-ERK1/2 (not ERK1/2), Nrf2 and HO-1 were significantly increased in the model group than those in the sham operation group (P<0.05). Compared with the model group, the expression levels of ApoE, p-ERK1/2, Nrf2 and HO-1 were further notably up-regulated (P<0.05), and those of p-NF-κB and IL-1ß proteins obviously down-regulated in the EA group (P<0.05). Immunoflorescence staining showed that the number of GFAP-positive cells was apparently increased in the model group compared with the sham operation group and observably decreased in the EA group relevant to the model group (P<0.05). CONCLUSION: EA can significantly improve locomotor function in SCI mice, which is associated with its effects in reducing inflammation, oxi-dative stress reactions and reactive astrocyte proliferation via up-regulating expression of ApoE, p-ERK1/2, and Nrf2/HO-1 (antioxidant pathway) and inhibiting IL-1ß and NF-κB expression.


Assuntos
Eletroacupuntura , Traumatismos da Medula Espinal , Animais , Feminino , Proteínas de Choque Térmico , Inflamação , Locomoção , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Medula Espinal
9.
Zhen Ci Yan Jiu ; 44(6): 391-8, 2019 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-31368260

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) combined with transplantation of Schwann cells (SCs) on limb locomotor, myelin sheath repair and expression of CD4 and CD8 in compressed spinal cord injury (CSCI) rats, so as to explore its mechanisms underlying improvement of CSCI. METHODS: A total of 45 female SD rats were randomly divided into normal control, model, EA, Schwann cell (SC) transplantation, and EA+SC transplantation groups (n=9 rats in each group). The CSCI model was established by laminectomy at T12-L2 and clip compression. Rats of the SC transplantation group accepted injection of the cultured SC suspension (2×106/6 µL) into the central, upper and lower sites of the injured spinal cord (5 mm in depth) 7-8 days after CSCI modeling. EA (2 Hz) was applied to bilateral "Zusanli" (ST36) and "Sanyinjiao" (SP6) for 10 min, once daily and 6 days a week for 3 weeks. The Basso, Beattie and Bresnahan locomotor rating scale (BBB scale) was used to evaluate the function state of CSCI. Morphological changes of the regional injured tissue were observed under light microscope after H.E. staining. The myelin sheath repair state and survival of SCs were detected by Luxol fast blue (LFB) staining and immunofluorescence histochemistry, and the expression of CD4, CD8 and P0 of the injured spinal cord was detected by Western blot. RESULTS: Compared with the normal control group, the BBB scores at the time-points of 0 d, and 1, 2, and 3 weeks were significantly decreased in the model group (P<0.001), and those of the EA+SC transplantation group at the 2nd and 3rd week were significantly higher than those of the model group (P<0.05). No significant changes of BBB scores were found after EA and SC transplantation relevant to the model group (P>0.05). LFB staining showed a disordered arrangement of the nerve fibers in the white matter, myelinociasis and obvious decrease of the medullated fibers in the model group, and these situations were relatively milder in both EA and SC transplantation groups and obviously milder in the EA+SC transplantation group. H.E. staining displayed that the structure of the injured region of the spinal cord was incomplete, accompanied with a large number of defect cavities and neuronal karyopyknosis in the model group, while the structure was relatively clear, with an increase of the normal neurons and fewer neuronal karyopyknosis in the EA+SC transplantation group. Compared with the normal control group, MBP in the model group was significantly decreased (P<0.001),and P0 was significantly increased (P<0.001). Compared with the model group, the expressions of MBP and P0 were significantly increased in the EA, SC transplantation, and EA+SC transplantation groups (P<0.01, P<0.001), and was significantly higher in the EA+SC transplantation group than in both EA and SC transplantation groups (P<0.001). The average immunofluorescence intensity of Hoechst33342-labeled SCs was significantly higher in the EA+SC transplantation group than in the SC transplantation group (P<0.05). After CSCI, the expression levels of spinal CD4, CD8 and P0 proteins had no significant changes in comparison with the normal control group (P>0.05), while after the intervention and in comparison with the model group, the expression levels of P0 protein were significantly increased in the EA, SC transplantation and EA+SC transplantation groups (P<0.05), and was significantly higher in the EA+SC transplantation group than in both EA and SC transplantation groups (P<0.05). The expression levels of CD4 and CD8 proteins were significantly lower in the EA+SC transplantation group than in the SC transplantation group (P<0.05).. CONCLUSION: EA+SCs transplantation can improve the locomotor function in CSCI rats, which may be related to its effects in increasing the survival of transplanted SCs to promote the remyelination and in reducing the immune rejecting reaction.


Assuntos
Eletroacupuntura , Remielinização , Traumatismos da Coluna Vertebral , Animais , Linfócitos T CD8-Positivos , Transplante de Células , Feminino , Ratos , Ratos Sprague-Dawley , Células de Schwann
10.
Opt Express ; 27(3): 1941-1957, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732240

RESUMO

We propose an on-chip mode converter via two cascaded Bragg reflection processes. A forward conversion between two guided modes can be achieved with the aid of an additional mode. The proposed structure is theoretically studied and simulated via the rigorous three-dimensional finite-difference time-domain (3D-FDTD) method. The bandwidth and central wavelength of the proposed mode converter can be adjusted according to our theoretical analysis and simulation results. By applying the similar design approaches as fiber Bragg gratings, conversion spectra with different shapes can be obtained. As an example, several mode converters with bandpass and sidelobe-reduced spectra are designed. We also investigate and verify the mode conversion by experiment. Therefore, the proposed method may pave a new path for the mode converters with desired conversion spectra.

11.
Biosens Bioelectron ; 86: 683-689, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27472402

RESUMO

Herein, a spatial-resolved electrochemiluminescene (ECL) ratiometry based on a closed biopolar electrode (BPE) is reported for the highly sensitive detection of prostate specific antigen (PSA). Au@g-C3N4 NCs as one ECL emitter were firstly coated on the cathode of BPE, while the anode of the BPE served for calibration via another ECL substance, Ru(bpy)3(2+). The electroneutrality across the BPE makes the reactions on each pole of BPE electrically coupled. Thus one electrochemical sensing reaction at one pole of BPE could be quantified at both ends. A composite, Pt-PAMAM-DNAzyme was assembled on the surface of cathode via DNA hybridization between probe DNA and PSA aptamer. It acted as an ECL quencher of g-C3N4 via resonance energy transfer (RET) and catalyzing the reduction of O2, the co-reactant of g-C3N4. Meanwhile, it could promote the ECL of Ru(bpy)3(2+) at anode, since the catalytic reduction of O2 at the cathode increased the faradiac current flowing through the BPE. Based on this signal composite, an ECL "off-on" phenomenon was observed at the cathode, after Pt-PAMAM-DNAzyme was "peeled off" by PSA. Conversely, at the anode, an "on-off" ECL changing was obtained. Therefore, a sensitive ratiometry for PSA detection was achieved with a linear range from 0.10 to 200ng/mL. Since the two ECL emitters were physically separated, the ratiometric system was relatively simple and neither optical filters nor spectrometer were required. The strategy combining the ECL ratiometry and BPE broadens the applications of BPE-ECL and shows good perspective in clinical application.


Assuntos
Técnicas Biossensoriais/instrumentação , Condutometria/instrumentação , Eletrodos , Medições Luminescentes/instrumentação , Antígeno Prostático Específico/sangue , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise Espaço-Temporal
12.
ACS Appl Mater Interfaces ; 8(7): 4434-41, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26824724

RESUMO

Facile and efficient detection of cancer cells at their preclinical stages is one of the central challenges in cancer diagnostics. A direct, rapid, highly sensitive and specific biosensor for detection of cancer biomarkers is desirable in early diagnosis and prognosis of cancer. In this work, we developed, for the first time, an easy and intuitive dispersion-dominated colorimetric strategy for cancer cell detection based on combining multi-DNA released from an aptamer scaffold with cyclic enzymatic amplification, which was triggered by aptamer DNA conformational switch and demonstrated by non-cross-linking gold nanoparticles (Au NPs) aggregation. First, five kinds of messenger DNAs (mDNAs) were aligned on the cancer cell aptamers modified on magnetic beads (MBs) to form mDNAs-Apt-MBs biocompatible nanosensors. In the presence of target cells, the aptamer would bind to the receptors on the cell membranes, and mDNAs would be released, resulting in the first amplification that one biological binding event would cause the release of multiple kinds of mDNAs simultaneously. After magnetic separation, the released mDNAs were introduced into the cyclic enzymatic amplification to cleave more single strand DNA (ssDNA) fragments. Instead of modification of Au NPs, these fragments and mDNAs could be adsorbed on the surface of Au NPs to prevent particle aggregation and ensure the stability and color of solution in high salt environments. The linear response for HL-60 cells in a concentration range from 10 to 10(4) cells was obtained with a detection limit of four cells in buffer solution. Moreover, the feasibility of the proposed strategy was demonstrated in a diluted serum sample. This dual signal amplification method can be extended to other types of cancer cells, which has potential application in point-of-care cancer diagnosis.


Assuntos
Técnicas Biossensoriais , Rastreamento de Células/métodos , Colorimetria/métodos , DNA/isolamento & purificação , Neoplasias/diagnóstico por imagem , Aptâmeros de Nucleotídeos/química , DNA/química , Ouro/química , Células HL-60 , Humanos , Nanopartículas Metálicas/química , Neoplasias/patologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-25090391

RESUMO

The complete mitochondrial genome of Heliconius pachinus has been reconstructed from the whole-genome Illumina sequencing data. The circular genome is 15,369 bp in length, and comprises the typical components: 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and 1 D-loop region. PCGs are mostly initiated with either the ATN codons (COII, COIII, Cytb, ND2, ND3, ND4, ND4L, ND5, ND6, ATP6 & ATP8) or the TTG codon (ND1); the COI gene may use the unusual CGA as its initiation codon, as suggested for other lepidopteran species. Some PCGs harbor TAG (ND3) or incomplete termination codon T (COI, COII & ND4), while the others use TAA as their termination codons. The nucleotide composition is highly asymmetric (39.2% A, 42.0% T, 7.7% G, 11.1% C) with an overall GC content of 18.8%.


Assuntos
Borboletas/genética , DNA Mitocondrial/genética , Genoma Mitocondrial/genética , Mitocôndrias/genética , Animais , Composição de Bases/genética , Sequência de Bases , Códon de Iniciação/genética , Códon de Terminação/genética , DNA Intergênico/genética , Tamanho do Genoma/genética , RNA Ribossômico/genética , RNA de Transferência/genética , Análise de Sequência de DNA
14.
Anal Chem ; 87(24): 12372-9, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26564425

RESUMO

Semiconductor nanocrystals usually suffer from weak electrogenerated chemiluminescence (ECL) emissions compared with conventional organic emitters. In this work, we propose, for the first time, a very convenient but effective way to greatly enhance ECL emission of semiconductor TiO2 nanotubes (NTs) by H2O2 and K2S2O8 as dual coreactants, generating ECL emission ca. 6.3 and 107 times stronger than that of K2S2O8 or H2O2 as an individual coreactant, respectively. Scanning electron microscopy, X-ray diffraction, and electron paramagnetic resonance spectral studies were carried out to investigate the ECL enhancement mechanism. The ECL enhancement of TiO2 NTs by the K2S2O8-H2O2 system was supposed to originate from the coordination of H2O2 to the TiO2 surface and the synergy effect between H2O2 and K2S2O8 in the ECL process. The coordination of H2O2 to the surface of TiO2 could stabilize the electrogenerated coreactant-related radical OH(•) (hydroxyl radical), which could obviously promote the amount of sulfate radical anion (SO4(•-)) near the electrode surface by inducing decomposition of K2S2O8 into SO4(•-) or inhibiting the consumption of SO4(•-) by its reaction with H2O. The holes (h(+)) released from SO4(•-) were injected into the valence band of TiO2, resulting in more TiO2(+), which combined with the electrons coming from the conduction band with an enhanced light emission. Moreover, this enhancement effect was also applicable to ECL of a CdS nanocrystal film on a glass carbon electrode, with ca. 2.74- and 148.3-fold enhanced ECL intensity correspondingly, indicating wide applications in the development of semiconductor nanocrystal-based ECL biosensors.

15.
Chem Commun (Camb) ; 51(70): 13504-7, 2015 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-26216522

RESUMO

A dual target-recycling amplification strategy for sensitive detection of microRNAs based on duplex-specific nuclease and catalytic hairpin assembly was reported for the first time.


Assuntos
Técnicas de Química Analítica/métodos , Desoxirribonucleases/metabolismo , MicroRNAs/análise , Técnicas de Amplificação de Ácido Nucleico , Catálise , MicroRNAs/isolamento & purificação
16.
Talanta ; 141: 97-102, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25966387

RESUMO

Here we have developed a sensitive cancer cell amplified detection method which combined Au NPs enhanced electrochemiluminescence (ECL) of CdS nanocrystals (NCs) film, with isothermal circular amplification reaction of polymerase. In DNA circular amplification detection system, hairpin DNA beacon/Au NPs composite modified CdS NCs film was used as an ECL emitter. Messenger DNA is hybridized with the aptamer modified on magnetic beads (MBs) to form MB-Au bioconjugates. In the presence of HL-60 cell, the aptamer would conjugate with the glycoprotein at cell surface and messenger DNA sequence would be released. The released messenger DNA sequence was then introduced into the cycle amplification system to trigger circular polymerizations. This assay allows us to determine the released messenger DNA equivalent to 10 cells and exhibits a significant specificity for HL-60 cells.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas/química , RNA Mensageiro/análise , Compostos de Cádmio/química , Células HL-60 , Humanos , Medições Luminescentes/métodos , Magnetismo , Técnicas de Amplificação de Ácido Nucleico , RNA Mensageiro/química , Sulfetos/química
17.
Anal Chem ; 86(23): 11513-6, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25403364

RESUMO

Photoelectrochemical (PEC) immunoassay has received increasing attention owing to its good analytical performance and attractive potential for future protein assay. This Letter represents a novel and general strategy for elegant PEC immunoassay of the important cardiac marker troponin T (cTnT) at neutral conditions. Specifically, we first developed an efficient CdS quantum dots (QDs)/TiO2 nanoparticles (NPs) photoelectrode, on the basis of which an exquisite ß-galactosidase (ß-Gal) catalytic system was integrated with sandwich immunobinding for probing cTnT. In pH 7.4, ß-Gal could catalyze the conversion of p-aminophenyl galactopyranoside (PAPG) to p-aminophenol (PAP), which could be easily photo-oxidized to p-quinone imine (PQI). Because the resulting photocurrent was directly related with the target concentration, an innovative PEC immunoassay could be realized for cTnT detection. The neutral operating condition of this protocol would greatly contribute to its wide applicability for protein assay. This work provides the first PEC immunoassay toward cardiac marker and, more significantly, opens a different perspective for future PEC immunoassay development through a general sensing protocol.


Assuntos
Compostos de Cádmio/química , Técnicas Eletroquímicas , Imunoensaio/métodos , Processos Fotoquímicos , Pontos Quânticos , Sulfetos/química , Titânio/química , beta-Galactosidase/metabolismo , Biocatálise , Eletrodos
18.
ScientificWorldJournal ; 2012: 907685, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23213305

RESUMO

Power sector is responsible for about 40% of the total CO2 emissions in the world and plays a leading role in climate change mitigation. In this study, measures that lower CO2 emissions from the supply side, demand side, and power grid are discussed, based on which, an integrated optimization model of CO2 mitigation (IOCM) is proposed. Virtual energy, referring to energy saving capacity in both demand side and the power grid, together with conventional energy in supply side, is unified planning for IOCM. Consequently, the optimal plan of energy distribution, considering both economic benefits and mitigation benefits, is figured out through the application of IOCM. The results indicate that development of demand side management (DSM) and smart grid can make great contributions to CO2 mitigation of power sector in China by reducing the CO2 emissions by 10.02% and 12.59%, respectively, in 2015, and in 2020.


Assuntos
Dióxido de Carbono/isolamento & purificação , Efeito Estufa/prevenção & controle , Resíduos Industriais/prevenção & controle , Resíduos Industriais/estatística & dados numéricos , Centrais Elétricas/estatística & dados numéricos , Energia Renovável/estatística & dados numéricos , Gerenciamento de Resíduos/estatística & dados numéricos , China , Efeito Estufa/estatística & dados numéricos , Modelos Teóricos , Integração de Sistemas
19.
Nanoscale Res Lett ; 6(1): 576, 2011 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-22040124

RESUMO

We report the initial results of GaAs and GaInP solar cells grown by all solid-state molecular-beam-epitaxy (MBE) technique. For GaAs single-junction solar cell, with the application of AlInP as the window layer and GaInP as the back surface field layer, the photovoltaic conversion efficiency of 26% at one sun concentration and air mass 1.5 global (AM1.5G) is realized. The efficiency of 16.4% is also reached for GaInP solar cell. Our results demonstrate that the MBE-grown phosphide-contained III-V compound semiconductor solar cell can be quite comparable to the metal-organic-chemical-vapor-deposition-grown high-efficiency solar cell.

20.
Mol Phylogenet Evol ; 57(1): 176-88, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20637294

RESUMO

Saruma henryi Oliv. (Aristolochiaceae) is an endangered herb endemic to China. In this study, chloroplast microsatellites (cpSSRs) and sequences of the atpB-rbcL intergenic spacers were employed to reveal its genetic diversity and phylogeographic patterns. We detected high within-species genetic diversity (H(T)=0.939 for cpSSR; H(T)=0.862 for atpB-rbcL) and pronounced among-population genetic differentiation (H(S)=0.182, G(ST)=0.811, R(ST)=0.9, F(ST)=0.93 for cpSSR; H(S)=0.238, G(ST)=0.724, N(ST)=0.758, F(ST)=0.79 for atpB-rbcL) with a strong phylogeographic pattern (R(ST)>G(ST), P<0.01 for cpSSR; N(ST)>G(ST), U=0.25 for atpB-rbcL). Eleven haplotypes were distinguished by cpSSRs and atpB-rbcL intergenic spacers, respectively. The molecular phylogenetic data, together with the geographic distribution of the haplotypes, suggested the existence of multiple localized glacial refugia in Mts. Qinling, eastern Mts. Bashan and the southeastern edge of Yunnan-Guizhou Plateau. Nested clade analysis (NCA) and population genetic analyses supported the limited gene flow (caused by low dispersal capacity and complex topography of its habitats) as the major factor responsible for the strong population differentiation and phylogeographic pattern. Past fragmentation and allopatric fragmentation were inferred as important processes responsible for the modern phylogeograhpic pattern. In addition, contiguous range expansions occurred in western Mts. Qinling and eastern Mts. Bashan.


Assuntos
Aristolochiaceae/genética , Evolução Molecular , Variação Genética , Filogenia , Aristolochiaceae/classificação , China , DNA de Cloroplastos/genética , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Fluxo Gênico , Genética Populacional , Haplótipos , Repetições de Microssatélites , Filogeografia , Análise de Sequência de DNA
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