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The selectivity control of Pd nanoparticles (NPs) in the direct CO esterification with methyl nitrite toward dimethyl oxalate (DMO) or dimethyl carbonate (DMC) remains a grand challenge. Herein, Pd NPs are incorporated into isoreticular metal-organic frameworks (MOFs), namely UiO-66-X (X=-H, -NO2 , -NH2 ), affording Pd@UiO-66-X, which unexpectedly exhibit high selectivity (up to 99 %) to DMC and regulated activity in the direct CO esterification. In sharp contrast, the Pd NPs supported on the MOF, yielding Pd/UiO-66, displays high selectivity (89 %) to DMO as always reported with Pd NPs. Both experimental and DFT calculation results prove that the Pd location relative to UiO-66 gives rise to discriminated microenvironment of different amounts of interface between Zr-oxo clusters and Pd NPs in Pd@UiO-66 and Pd/UiO-66, resulting in their distinctly different selectivity. This is an unprecedented finding on the production of DMC by Pd NPs, which was previously achieved by Pd(II) only, in the direct CO esterification.
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Clinical tracking of chimeric antigen receptor (CAR) T cells in vivo by positron emission tomography (PET) imaging is an area of intense interest. But the long-lived positron emitter-labeled CAR T cells stay in the liver and spleen for days or even weeks. Thus, the excessive absorbed effective dose becomes a major biosafety issue leading it difficult for clinical translation. In this study we used 68Ga, a commercially available short-lived positron emitter, to label CAR T cells for noninvasive cell tracking in vivo. CAR T cells could be tracked in vivo by 68Ga-PET imaging for at least 6 h. We showed a significant correlation between the distribution of 89Zr and 68Ga-labeled CAR T cells in the same tissues (lungs, liver, and spleen). The distribution and homing behavior of CAR T cells at the early period is highly correlated with the long-term fate of CAR T cells in vivo. And the effective absorbed dose of 68Ga-labeled CAR T cells is only one twenty-fourth of 89Zr-labeled CAR T cells, which was safe for clinical translation. We conclude the feasibility of 68Ga instead of 89Zr directly labeling CAR T cells for noninvasive tracking of the cells in vivo at an early stage based on PET imaging. This method provides a potential solution to the emerging need for safe and practical PET tracer for cell tracking clinically.
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Rastreo Celular/métodos , Radiofármacos/química , Receptores Quiméricos de Antígenos/metabolismo , Linfocitos T/metabolismo , Animales , Linfoma de Burkitt/terapia , Línea Celular Tumoral , Estudios de Factibilidad , Radioisótopos de Galio/química , Humanos , Inmunoterapia Adoptiva , Oxiquinolina/química , Oxiquinolina/farmacocinética , Tomografía de Emisión de Positrones/métodos , Radioisótopos/química , Radiofármacos/farmacocinética , Linfocitos T/química , Circonio/químicaRESUMEN
Nonconjugated red fluorescent polymers have been increasingly studied to improve the biocompatibility and penetration depth over conventional fluorescent materials. However, the accessibility of such polymers remains challenging due to the scarcity of nonconjugated fluorophores and lacking relevant mechanism of red-shifted fluorescence. Herein, we discovered that the combination of hydrogen bonding and π-π stacking interactions provides nonconjugated poly(amide-imide) with a large bathochromic shift (>100 nm) from blue-green fluorescence to red emission. The amphiphilic PEGylated poly(amide-imide) derived from in situ PEGylation self-assembled into nanovesicles in water, which isolated the aminosuccinimide fluorophore from the solvents and suppressed the hydrogen bonds formation between aminosuccinimide fluorophores and water. Therefore, the fluorescence of PEGylated poly(amide-imide) in water was soundly retained. Furthermore, the strong hydrogen bonding and hydrophobic interactions with water provided PEGylated poly(amide-imide) with a reversible thermoresponsiveness and presented a concentration-dependent behavior. Finally, accompanied by the excellent biostability and photostability, PEGylated poly(amide-imide) exhibited as a good candidate for cell imaging.
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Amidas/química , Colorantes Fluorescentes/química , Imidas/química , Polímeros/química , Fluorescencia , Enlace de Hidrógeno , Interacciones Hidrofóbicas e HidrofílicasRESUMEN
Bombesin (BBN) is a peptide exhibiting high affinity for the gastrin-releasing peptide receptor (GRPR), which is overexpressed on several types of cancers. Various GRPR antagonists and agonists have been labeled with radiometals for positron emission tomography (PET) imaging of GRPR-positive tumors. However, unfavorable hepatobiliary excretion such as high intestinal activity may prohibit their clinical utility for imaging abdominal cancer. In this study, the modified BBN peptide with a new hydrophilic linker was labeled with (68)Ga for PET imaging of GRPR-expressing PC-3 prostate cancer xenograft model. GRPR antagonists, MATBBN (Gly-Gly-Gly-Arg-Asp-Asn-D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHCH2CH3) and ATBBN (D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHCH2CH3), were conjugated with 1,4,7-triazacyclononanetriacetic acid (NOTA) and labeled with (68)Ga. Partition coefficient and in vitro stability were also determined. GRPR binding affinity of both tracers was investigated by competitive radioligand binding assay. The in vivo receptor targeting potential and pharmacokinetic of (68)Ga-NOTA-MATBBN were also evaluated in PC-3 prostate tumor model and compared with those of (68)Ga-NOTA-ATBBN. NOTA-conjugated BBN analogs were labeled with (68)Ga within 20 min with a decay-corrected yield ranging from 90 to 95 % and a radiochemical purity of more than 98 %. The specific activity of (68)Ga-NOTA-MATBBN and (68)Ga-NOTA-ATBBN was at least 16.5 and 11.9 GBq/µmol, respectively. The radiotracers were stable in phosphate-buffered saline and human serum. (68)Ga-NOTA-MATBBN was more hydrophilic than (68)Ga-NOTA-ATBBN, as indicated by their log P values (-2.73 ± 0.02 vs. -1.20 ± 0.03). The IC50 values of NOTA-ATBBN and NOTA-MATBBN were similar (102.7 ± 1.18 and 124.6 ± 1.21 nM). The accumulation of (68)Ga-labeled GRPR antagonists in the subcutaneous PC-3 tumors could be visualized via small animal PET. The tumors were clearly visible, and the tumor uptakes of (68)Ga-NOTA-MATBBN and (68)Ga-NOTA-ATBBN were determined to be 4.19 ± 0.32, 4.00 ± 0.41, 2.93 ± 0.35 and 4.70 ± 0.40, 4.10 ± 0.30, 3.14 ± 0.30 %ID/g at 30, 60, and 120 min, respectively. There was considerable accumulation and retention of (68)Ga-NOTA-ATBBN in the liver and intestines. In contrast, the abdominal area does not have much retention of (68)Ga-NOTA-MATBBN. Biodistribution data were in accordance with the PET results, showing that (68)Ga-NOTA-MATBBN had more favorable pharmacokinetics and higher tumor to background ratios than those of (68)Ga-NOTA-ATBBN. At 1 h postinjection, the tumor to liver and intestine of (68)Ga-NOTA-MATBBN were 8.05 ± 0.56 and 21.72 ± 3.47 and the corresponding values of unmodified counterpart were 0.85 ± 0.23 and 3.45 ± 0.43, respectively. GRPR binding specificity was demonstrated by reduced tumor uptake of radiolabeled tracers after coinjection of an excess of unlabeled BBN peptides. (68)Ga-NOTA-MATBBN exhibited GRPR-targeting properties both in vitro and in vivo. The favorable characterizations of (68)Ga-NOTA-MATBBN such as convenient synthesis, specific GRPR targeting, high tumor uptake, and satisfactory pharmacokinetics warrant its further investigation for clinical cancer imaging.
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Bombesina/metabolismo , Radioisótopos de Galio , Marcaje Isotópico/métodos , Receptores de Bombesina/metabolismo , Animales , Bombesina/análogos & derivados , Línea Celular Tumoral , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos con 1 Anillo , Xenoinjertos , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias , Tomografía de Emisión de Positrones/métodos , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/metabolismo , Distribución TisularRESUMEN
OBJECTIVE: To demonstrate the hypothesis that aerobic exercise training inhibits the development of insulin resistance through IL-6 and probe into the possible molecular mechanism about it. METHODS: Rats were raised with high-fat diets for 8 weeks to develop insulin resistance, and glucose infusion rates (GIRs) were determined by hyperinsulinemic-euglycemic clamping to confirm the development of insulin resistance. Aerobic exercise training (the speed and duration time in the first week were respectively 16 m/min and 50 min, and speed increased 1m/min and duration time increased 5 min every week following it) and/or IL-6shRNA plasmid injection (rats received IL-6shRNA injection via the tail vein every two weeks) were adopted during the development of insulin resistance. The serum IL-6, leptin, adiponectin, fasting blood glucose, fasting serum insulin, GIR, IL-6 gene expression levels, p-p38 in various tissues and p-STAT3/t-STAT3 ratio in the liver were measured. RESULTS: Rats fed with high-fat diets for 8 weeks were developed insulin resistance and the IL-6mRNA levels of IL-6shRNA injection groups in various tissues were significantly lower than those of control group (P<0.05), respectively. The development of insulin resistance in exercise rats significantly decreased, however, compared with that, the GIR of exercise rats injected by IL-6shRNA was lower (P<0.05). The IL-6mRNA levels were highest in the fat tissue and lowest in the skeletal muscles in all the rats. The serum adiponectin levels decreased (P<0.05) following the development of insulin resistance, and it increased (P<0.05) when the rats were intervened by aerobic exercise training for 8 weeks at the same time. However, there were not significant differences when serum leptin concentrations were compared (P>0.05). The p-p38 significantly increased in the rats fed with high-fat diets, however, p-p38 of the exercise high-fat diets rats in the liver and fat tissues significantly decreased than that (P<0.05). The changes of p-p38 in exercise rats injected by IL-6shRNA were irregular. The activation of STAT3 in the liver significantly increased (P<0.05) following the development of insulin resistance, and it decreased (P<0.05) when the rats were intervened by aerobic exercise training for 8 weeks at the same time, and the gene silencing of IL-6 did not have effects on the activation of STAT3 in the liver (P>0.05). CONCLUSIONS: In conclusion, aerobic exercise training prevented the development of insulin resistance through IL-6 to a certain degree. The gene expression and secretion of IL-6 could inhibit the development of insulin resistance. The mechanism of the effects were possibly related with elevating the levels of serum adiponectin, and/or inhibiting the activation of STAT3 in the liver and p38MAPK in the skeletal muscles, liver and fat tissues.
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Regulación de la Expresión Génica , Resistencia a la Insulina/genética , Interleucina-6/genética , Condicionamiento Físico Animal , Interferencia de ARN , Adiponectina/sangre , Animales , Dieta Alta en Grasa , Interleucina-6/sangre , Leptina/sangre , Hígado/metabolismo , Masculino , Músculo Esquelético/metabolismo , Plásmidos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , Ratas , Ratas Sprague-Dawley , Factor de Transcripción STAT3/metabolismo , Proteínas Quinasas p38 Activadas por MitógenosRESUMEN
Variations in the dynein axonemal heavy chain gene, dynein axonemal heavy chain 6 (DNAH6), lead to multiple morphological abnormalities of the flagella. Recent studies have reported that these deficiencies may result in sperm head deformation. However, whether DNAH6 is also involved in human acrosome biogenesis remains unknown. The purpose of this study was to investigate DNAH6 gene variants and their potential functions in the formation of defective sperm heads and flagella. Whole-exome sequencing was performed on a cohort of 375 patients with asthenoteratozoospermia from the First Affiliated Hospital of Anhui Medical University (Hefei, China). Hematoxylin and eosin staining, scanning electron microscopy, and transmission electron microscopy were performed to analyze the sperm morphology and ultrastructure. Immunofluorescence staining and Western blot analysis were conducted to examine the effects of genetic variants. We identified three novel deleterious variants in DNAH6 among three unrelated families. The absence of inner dynein arms and radial spokes was observed in the sperm of patients with DNAH6 variants. Additionally, deficiencies in the acrosome, abnormal chromatin compaction, and vacuole-containing sperm heads were observed in these patients with DNAH6 variants. The decreased levels of the component proteins in these defective structures were further confirmed in sperm from patients with DNAH6 variants using Western blot. After intracytoplasmic sperm injection (ICSI) treatment, the partner of one patient with a DNAH6 variant achieved successful pregnancy. Overall, novel variants in DNAH6 genes that contribute to defects in the sperm head and flagella were identified, and the findings indicated ICSI as an effective clinical treatment for such patients.
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OBJECTIVE: To investigate clinical effect and safety of in vitro maturation (IVM) of human immature oocytes in infertile women with polycystic ovary syndrome by comparing with conventional in vitro fertilization(IVF)and intracytoplasmic sperm injection(ICSI). METHODS: From Jan. 2003 to Dec. 2009, 157 infertile women with PCOS underwent 162 cycles IVM in Center for Reproductive Medicine, the First Affiliated Hospital of Anhui Medical University. In the mean time, 109 patients with PCOS underwent 114 IVF/ICSI cycles as control group 1 and 106 patients with other factors underwent 106 IVF/ICSI cycles as control group 2. Treatment and outcome of pregnancy and infant were compared among those 3 groups. RESULTS: No statistically significant difference were found in terms of the positive rate of hCG in urine [35.7% (56/157), 42.2% (46/109), 44.3% (47/106)], the rate of clinical pregnancy [29.3% (46/157), 37.6% (41/109), 41.5% (44/106)], the rate of entopic pregnancy [1.9% (3/157), 1.8% (2/109), 0.9% (1/106)], the rate of miscarriage [18.6% (8/43), 12.8% (5/39), 20.9% (9/43)] and the rate of live-birth [22.3% (35/157), 31.2% (34/109), 32.1% (34/106)] among three groups (IVM group, control group 1, control group 2, P > 0.05). The rate of preterm labor, low weight newborn, mean birth weight, ratio of male to female did not show significantly difference among 3 groups (P > 0.05). The average control ovarian stimulation was 6 days, the median dose of gonadotropin (Gn) was 675 IU, and the total hospital cost was (8392 ± 1328) RMB in IVM group, which were statistically lower than those in the other two control groups (P < 0.01). The rate of multiple pregnancy was 4.7% (2/43) and ovarian hyperstimulation syndrome (OHSS) 0 in IVM group, which were significantly lower than those in the other control group (P < 0.01). CONCLUSION: In vitro maturation is an effective treatment in infertile women with PCOS, it could obtain the similar pregnancy outcome and reduce total cost, the dosage of gonadotropin-releasing hormone and rate of OHSS compared with conventional IVF/ICSI.
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Infertilidad Femenina/terapia , Oocitos/fisiología , Síndrome del Ovario Poliquístico/terapia , Técnicas Reproductivas Asistidas , Adulto , Peso al Nacer , Estudios de Casos y Controles , Técnicas de Cultivo de Célula , Células Cultivadas , Transferencia de Embrión , Femenino , Fertilización In Vitro , Humanos , Recién Nacido , Infertilidad Femenina/etiología , Masculino , Oocitos/citología , Oogénesis , Inducción de la Ovulación/métodos , Síndrome del Ovario Poliquístico/complicaciones , Embarazo , Resultado del Embarazo , Estudios RetrospectivosRESUMEN
Production of ethylene glycol from coal is a particularly interesting route as it is an economic alternative to the petrochemical-based route. In this process, effectively generating dimethyl oxalate (DMO) is a crucial step by CO oxidative coupling reaction under Pd-based catalysts. However, the aggregation of Pd species over the support is still an issue that relates to the deterioration of catalytic activity and stability. To this end, enhancing the metal-support interaction is urgently required. In this work, hierarchical Nb2O5 (H-Nb2O5) microspheres with abundant oxygen defects were synthesized to anchor the Pd species thus promoting the electron transfer between Pd species and Nb species associated with the generation of interfacial Pd-NbOx sites. Besides, the thinned electron density of Pd species resulting from the electron-withdrawing effect of Nb species is beneficial for activating the adsorbed CO molecules, leading to superior catalytic activity. The Pd/H-Nb2O5 catalyst exhibited 63.1% of CO conversion (theoretical maximum conversion: 64.3%) and 92.9% of DMO selectivity, with a DMO weight time yield of 1297.9 g kgcat.-1 h-1, and remained robust even after 50 h of time on stream evaluation. Current work provides a deep insight into the CO activation mechanism and helps improve the catalytic stability by boosting interfacial electron interaction via oxygen defects induction, and also sheds light on the design and synthesis of high-performance catalysts in other heterogeneous catalysis fields.
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OBJECTIVE: To investigate the association between polymorphism of cytochrome P450 subfamily XIA polypeptide 1 (CYP11A1) gene and polycystic ovarian syndrome (PCOS) in Chinese population. METHODS: From May 2005 to Dec. 2008, 290 PCOS cases treated in the First affiliated hospital of Anhui Medical University matched with 344 reproductive women as controls were enrolled in this study. Genotypes of 7 tagging single nucleotide polymorphisms (tSNP, rs12438594, rs4077582, rs9806234, rs16968477, rs4887139, rs1843090, rs11632698) covering CYP11A1 gene (r(2) > or = 0.8) and 3 microsatellite markers (D15S1547, D16S520, D15S1546) were chosed from the phase II database of Han population in HapMap data. Genotype and frequency of allele were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and haplotype of gene polymorphism were analyzed in 290 PCOS cases and 344 controls. RESULTS: Among 7 tSNPs and 3 microsatellite markers, the frequency of rs4077582, D15S1547, D15S1546 and rs11632698 between two groups reached statistical difference (P = 0.010, 0.044, 0.018 and 0.026). The allele frequency of rs4077582, rs4887139, rs1843090, D15S1547 and D16S520 showed significant difference between two groups (P = 0.002, 0.048, 0.030, 0.001 and 0.024). Among 5 haplotype of CYP11A1 (ACGCA13/6/9AG, ACGTA16/6/11AA, GCACG12/8/8AA, GTACA14/4/7GG, GTGCA13/6/7AG), the frequency of GTACA14/4/7GG and ACGCA13/6/9AG were 7.8% (45/580) and 25.3% (147/580) in PCOS group and 11.9% and 19.6% in control group, which showed statistical difference (P < 0.05). There was no significant difference in the level of serum androgen at difference genotype from rs4077582 between two groups (P > 0.05). CONCLUSION: The polymorphism of CYP11A1 gene was associated with PCOS, however, the relationship between gene sequence covered by tSNP/microsatellite markers and hyperandrogenism of PCOS should be further investigated.
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Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Repeticiones de Microsatélite , Síndrome del Ovario Poliquístico/genética , Polimorfismo de Nucleótido Simple , Adulto , Alelos , Estudios de Casos y Controles , China/etnología , Cartilla de ADN , Estradiol/sangre , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Síndrome del Ovario Poliquístico/etnología , Reacción en Cadena de la Polimerasa/métodos , Testosterona/sangre , Adulto JovenRESUMEN
With the in situ-generated [Pb(MCP)4]2+ (HMCP+ = 1-methyl-4-(carboxyl)pyridinium) or [M(phen)3]2+ (M = Co, Fe and Ni; phen = 1,10-phenanthroline) complexes as structural directing agents and charge-balancing ions, we solvothermally synthesized and structurally characterized four new organic-inorganic hybrid iodoplumbates. Compound K2[Pb(MCP)4]Pb3I10 (1) represents the first K+ and [Pb(MCP)4]2+ co-templated hybrid haloplumbate, and exhibits a curve-like anionic layer of [Pb3I10]n4n-. Compounds [M(phen)3]Pb2I6·CH3CN (M = Co (2), Fe (3) and Ni (4)) have isostructural phases, and feature a one-dimensional (1D) [Pb2I6]n2n- anionic chain characteristic of pyramid-like [PbI5] units. The optical property studies show that compounds 1-4 exhibit semiconductor behaviors with the band gaps of 1.98-2.68 eV. In addition, the title compounds exhibited interesting photoelectrical responsive properties, with the photocurrent density in the order of 1 > 3 > 2 > 4. The thermal stabilities of the title compounds 1-4, as well as the theoretical band structure and density of states (DOS) of compounds 1 and 2 have also been studied.
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Yilong Lake, a shallow, plateau lake, is the ninth largest water body in the Yunnan Province, China. In order to figure out the characteristics of phytoplankton communities in different regions of this lake, the phytoplankton and environmental factors in the west region, east region, and in a submerged macrophytes restoration demonstration region were monthly investigated and analyzed from August 2013 to July 2014. The results showed that the habitats in different regions were spatially heterogeneous. Total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH4+-N), five-day biochemical oxygen demand (BOD5), transparency (SD), turbidity (Turb.), and electrical conductivity (EC) had no significant differences between the demonstration region and the west region, but these two regions showed significant differences in comparison with the east region (P<0.05). The largest phytoplankton density was Cyanophyta and the dominant species in the three regions were different. Mersmopedia tenuissima had the highest dominance in the west region; Cylindrospermopsis raciborskii and Pseudanabaena limntica were the most dominant taxa in the east region; while Merismopedia tenuissima and Anabaenopsis sp. were dominant in the O. uminata restoration demonstration region. PCoA compared the ß diversity of phytoplankton communities in the three different regions based on the entire year investigations. It was found that the community structures of the west region and O. uminata restoration demonstration region were similar (P>0.05), but they were significantly different from the community from the east region (P<0.01). Redundant analysis (RDA) showed that TN, TP, BOD5, and SD were the main environmental factors affecting the distribution of phytoplankton community in Yilong Lake. In addition, NH4+-N, EC, permanganate index, and pH also have a certain effect on the phytoplankton community.
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Lagos , Fitoplancton/clasificación , Fitoplancton/crecimiento & desarrollo , Análisis de la Demanda Biológica de Oxígeno , China , Monitoreo del Ambiente , Nitrógeno/análisis , Fósforo/análisis , Calidad del AguaRESUMEN
The characterization of products produced from hydrothermal liquefaction of algal biomass is helpful to better understand the effect of different kinds of raw materials on the properties of the product fractions. The data presented in this article are related to the research article entitled "Integration of hydrothermal liquefaction and supercritical water gasification for the improvement of energy recovery from algal biomass" (Duan et al., 2018) [1]. In this data article, the compositions of gaseous products produced from hydrothermal liquefaction of eight different algae feedstocks at 350⯰C for 60â¯min were analyzed by gas chromatography. The molecular and elemental compositions of the crude bio-oils produced from hydrothermal liquefaction of eight different algae feedstocks at 350⯰C for 60â¯min were analyzed by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry and organic elemental analyzer. The color of aqueous phases before and after they were subjected to supercritical water gasification was recorded by a high-resolution camera.
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BACKGROUND: In this study, a two-step processing method (hydrothermal liquefaction followed by catalytic upgrading) was used to produce upgraded bio-oil. A comprehensive screening analysis of algal species, including four microalgae and four macroalgae, was conducted to bridge the gap between previous accounts of microalgae and macroalgae hydrothermal liquefaction and the upgrading process of the resulting crude bio-oils. RESULTS: Hydrothermal liquefaction using eight algal biomasses was performed at 350 °C for 1 h. The microalgae always produced a higher crude bio-oil yield than the macroalgae due to their high lipid content, among which Schizochytrium limacinum provided the maximum crude bio-oil yield of 54.42 wt%. For microalgae, higher amounts of N in the biomass resulted in higher amounts of N in the crude bio-oil; however, contrary results were observed for the macroalgae. The crude bio-oils generated from both the microalgae and macroalgae were characterized as having a high viscosity, total acid number, and heteroatom content, and they were influenced by the biochemical compositions of the feedstocks. Next, all eight-crude bio-oils were treated at 400 °C for 2 h with 10 wt% Ru/C using tetralin as the hydrogen donor. The hydrogen source was provided after tetralin was transformed to naphthalene. All the upgraded bio-oils had higher energy densities and significantly lower N, O, and S contents and viscosities than their corresponding crude bio-oils. However, the H/C molar ratio of the upgraded bio-oils decreased due to the absence of external hydrogen relative to the crude bio-oils. The S content of the upgraded bio-oil produced from upgrading the Schizochytrium limacinum crude bio-oil was even close to the 50 ppm requirement of China IV diesel. CONCLUSIONS: Microalgae are better feedstocks than macroalgae for liquid fuel production. Biochemical components have a significant impact on the yield and composition of crude bio-oil. Tetralin does not perform as well as external hydrogen for controlling coke formation. The S content of the upgraded bio-oil can be reduced to 76 ppm for the crude bio-oil produced from Schizochytrium limacinum. Upgraded bio-oils have similar properties to those of naphtha and jet fuel.
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A comprehensive comparison of hydrothermal liquefaction (HTL) to the pyrolysis of duckweed was conducted to determine the yields and components of the crude bio-oils and their distillates. The upgrading behaviors of the distillates were thoroughly investigated with the use of used engine oil as a solvent. With all other variables fixed, HTL produced crude bio-oil with a lower H/C ratio (1.28⯱â¯0.03) than pyrolysis did (1.45⯱â¯0.04). However, its distillates had a higher H/C ratio (1.60⯱â¯0.05) and total yield (66.1⯱â¯2.0â¯wt%) than pyrolysis (1.46⯱â¯0.04 and 47.2⯱â¯1.4â¯wt%, respectively). Phenolics and nitrogenous heterocycles constituted relatively major proportions of the two crude bio-oils and most of their distillates. Obvious differences in molecular composition between the two crude bio-oils and their distillates were ascribed to the distinct impacts of HTL and pyrolysis and were affected by the distillate temperature. Co-hydrotreating with used engine oil (UEO) provided the upgraded bio-oils much higher H/C ratios (~1.78⯱â¯0.05) and higher heating values (~45.5⯱â¯1.4â¯MJ·kg-1), as well as much lower contents of N, O and S compared to their initial distillates. Aromatics and alkanes constituted a large proportion in most of upgraded bio-oils. N removal from the pyrolysis distillates was easier than from the HTL distillates. Distinct differences in yields and molecular compositions for the upgraded bio-oils were also attributed to the different influences associated with the two conversion routes.
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Supercritical water gasification (SCWG) of the microalga Chlorella pyrenoidosa was examined with a catalyst mixture of Ru/C and Rh/C in a mass ratio of 1:1. The influences of temperature (380-600°C), water density (0-0.197g/cm3), and catalyst loading (0-20wt%) on the yields and composition of the gaseous products and the gasification efficiency were examined. The temperature and water density significantly affected the SCWG of the microalgae. The hydrogen gasification efficiency was more dependent on the temperature, while the carbon gasification efficiency was more dependent on the water density. The gaseous products mainly consisted of CH4, H2, CO, and CO2, with smaller amounts of C2-C3 hydrocarbons. CH4 made up half of the mole fraction of the gaseous products under most reaction conditions. A synergistic effect between Ru/C and Rh/C existed during the SCWG of the microalgae, and this effect favored the production of CH4. The role of the catalyst mixture became indistinct at higher temperatures. Hydrogen atoms from the water were transferred to the gaseous products during the SCWG, leading to hydrogen gasification efficiencies that exceeded 100%. The main components of the bio-oil were aromatics and nitrogen-containing compounds, and the main aromatics consisted of azulene and anthracene. The nitrogen-containing compounds are potential poisons to the catalyst mixture.
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Chlorella/fisiología , Eliminación de Residuos Líquidos/métodos , Contaminantes del Agua/metabolismo , Carbono , Catálisis , Gases , Calor , Hidrógeno , Aguas del Alcantarillado , TemperaturaRESUMEN
@#Objective To investigate the current status of occupational hazards and prevention and control of occupational , - Methods , diseases in micro small and medium sized manufacturing enterprises in Jiangxi Province. A total of 1 034 micro - small and medium sized manufacturing enterprises in Jiangxi Province were selected as the research subjects using a stratified cluster sampling method. The exposure of occupational hazards and the implementation of occupational hazards prevention and Results , control measures were investigated. Among the 1 034 enterprises the small and micro enterprises accounted for , 91.5%. The enterprises with serious occupational hazards were mainly concentrated in metallurgy building materials industry , and machinery equipment and electrical appliance manufacturing industry. The exposure rate of occupational hazard factors in , , ( vs the categories of occupational hazard factors from high to low was physical factors dust and chemical factors 78.9% 52.8% vs ,P ) ( ), , 25.0% <0.01 . The exposure rate from high to low was metallurgy and building materials industry 60.8% machinery ( ), , equipment and electrical equipment manufacturing industry 42.9% light industry textile and tobacco processing industry ( ), , ( )(P ) 32.0% chemical petrochemical and pharmaceutical industry 21.0% <0.01 . Noise exposure accounted for 98.3% in the workers exposed to physical factors. The implementation rate of prevention and control measures for occupational hazards , in enterprises from high to low was the staffing of occupational health management personnel the establishment of , , occupational health management institutions the establishment of occupational health management systems the detection , , of occupational hazards the evaluation of the control effect of occupational hazards of construction projects and the - ( vs vs vs vs vs ,P ) pre evaluation of occupational hazards of construction projects 32.5% 25.7% 23.7% 16.2% 6.9% 4.2% <0.01 . Conclusion The focus of prevention and control of occupational hazards in manufacturing industry in Jiangxi Province is noise , - and dust in small and micro metallurgy and building materials industry. Most of the micro small and medium sized manufacturing enterprises have not carried out the detection of occupational hazards and evaluation of occupational hazards in accordance with the law. The situation of occupational disease prevention and control is still challenging.
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@#Objective To investigate the current status of occupational hazards and prevention and control of occupational , - Methods , diseases in micro small and medium sized manufacturing enterprises in Jiangxi Province. A total of 1 034 micro - small and medium sized manufacturing enterprises in Jiangxi Province were selected as the research subjects using a stratified cluster sampling method. The exposure of occupational hazards and the implementation of occupational hazards prevention and Results , control measures were investigated. Among the 1 034 enterprises the small and micro enterprises accounted for , 91.5%. The enterprises with serious occupational hazards were mainly concentrated in metallurgy building materials industry , and machinery equipment and electrical appliance manufacturing industry. The exposure rate of occupational hazard factors in , , ( vs the categories of occupational hazard factors from high to low was physical factors dust and chemical factors 78.9% 52.8% vs ,P ) ( ), , 25.0% <0.01 . The exposure rate from high to low was metallurgy and building materials industry 60.8% machinery ( ), , equipment and electrical equipment manufacturing industry 42.9% light industry textile and tobacco processing industry ( ), , ( )(P ) 32.0% chemical petrochemical and pharmaceutical industry 21.0% <0.01 . Noise exposure accounted for 98.3% in the workers exposed to physical factors. The implementation rate of prevention and control measures for occupational hazards , in enterprises from high to low was the staffing of occupational health management personnel the establishment of , , occupational health management institutions the establishment of occupational health management systems the detection , , of occupational hazards the evaluation of the control effect of occupational hazards of construction projects and the - ( vs vs vs vs vs ,P ) pre evaluation of occupational hazards of construction projects 32.5% 25.7% 23.7% 16.2% 6.9% 4.2% <0.01 . Conclusion The focus of prevention and control of occupational hazards in manufacturing industry in Jiangxi Province is noise , - and dust in small and micro metallurgy and building materials industry. Most of the micro small and medium sized manufacturing enterprises have not carried out the detection of occupational hazards and evaluation of occupational hazards in accordance with the law. The situation of occupational disease prevention and control is still challenging.
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Pancreatic cancer (PC) is a major health problem. Conventional imaging modalities show limited accuracy for reliable assessment of the tumor. Recent researches suggest that molecular imaging techniques with tracers provide more biologically relevant information and are benefit for the diagnosis of the cancer. In addition, radiopharmaceuticals also play more important roles in treatment of the disease. This review summaries the advancement of the radiolabeled compounds in the theranostics of PC.
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Overexpression of the gastrin-releasing peptide receptor (GRPR) in prostate cancer provides a promising target for detection the disease. MATBBN is a new bombesin analog originating from the GRPR antagonists with a hydrophilic linker. In this study NOTA-conjugated MATBBN was labeled by the Al(18)F method and the potential of (18)F-Al-NOTA-MATBBN for prostate tumor PET imaging was also evaluated. NOTA-MATBBN was radiolabeled with (18) F using Al(18)F complexes. Partition coefficient, in vitro stability and GRPR binding affinity were also determined. PET studies were performed with (18)F-Al-NOTA-MATBBN in PC-3 tumor-bearing mice. (18)F-Al-NOTA-MATBBN can be produced within 30 min with a decay-corrected yield of 62.5 ± 2.1% and a radiochemical purity of >98%. The logP octanol-water value for the Al(18)F-labeled BBN analog was -2.40 ± 0.07 and the radiotracer was stable in phosphate-buffered saline and human serum for 2 h. The IC50 values of displacement for the (18)F-Al-NOTA-MATBBN with MATBBN was 126.9 ± 2.75 nm. The PC-3 tumors were clearly visible with high contrast after injection of the labeled peptide. At 60 min post-injection, the tumor uptakes for (18)F-Al-NOTA-MATBBN and (18)F-FDG were 4.59 ± 0.43 and 1.98 ± 0.35% injected dose/g, and tumor to muscle uptake radios for two tracers were 6.77 ± 1.10 and 1.78 ± 0.32, respectively. Dynamic PET revealed that (18) F-Al-NOTA-MATBBN was excreted mainly through the kidneys. GRPR-binding specificity was also demonstrated by reduced tumor uptake of (18)F-Al-NOTA-MATBBN after coinjection with excess unlabeled MATBBN peptide at 1 h post-injection. NOTA- MATBBN could be labeled rapidly with (18)F using one step method. (18)F-Al-NOTA-MATBBN may be a promising PET imaging agent for prostate cancer.
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Bombesina/química , Radioisótopos de Flúor/química , Tomografía de Emisión de Positrones , Neoplasias de la Próstata/diagnóstico por imagen , Animales , Línea Celular Tumoral , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos con 1 Anillo , Humanos , Masculino , Ratones , Neoplasias de la Próstata/patología , RadiografíaRESUMEN
OBJECTIVE: The purpose of this study was to investigate the therapy effects of intratumoral administration of (32)P-CP-PLLA particles in a rabbit VX2 lung tumor model. METHODS: 16 rabbits with tumors were randomly divided into 4 groups. 4 rabbits served as untreated controls, and others received intratumoral administration of (32)P-CP-PLLA particles with CT guidance. The total radioactivities in treated groups were as follows: a low activity was 93 MBq (n=4) (group 1), a medium activity was 185 MBq (n=4) (group 2) and a high activity was 370 MBq (n=4) (group 3). Brachytherapy treated VX2 tumors underwent (18)F-FDG PET/CT at 0 day, 3 day, 7 day and 14 day postinjection. In control group, (18)F-FDG PET/CT images were acquired at the same time points but without any treatment. Bremsstrahlung SPECT images were performed at 14 days after intratumoral brachytherapy in treated groups. After Bremsstrahlung SPECT and last (18)F-FDG PET/CT imagings, the rabbits were euthanized and the tumors were removed for histological examination. RESULTS: Bremsstrahlung SPECT images study indicated that there was no leakage of (32)P out of the injection site at 14 days after treatment. Compared with the control, the tumor volumes in treated groups significantly decreased, and (32)P-CP-PLLA particle produced a reduction in maximum or mean SUV of VX2 tumor (p<0.05). The percentage changes in maximum and mean SUV gradually decreased in group 1 and group 2 from day 3 to day 14 (p<0.05). A transient increase in (18)F-FDG accumulation at group 3 occurred due to the inflammatory reaction elements. Activity dependence was seen in HE and PCNA staining after 14 days treatment among three treated groups (p<0.05). CONCLUSIONS: Our data suggested that (32)P-CP-PLLA particle localized on the injecting sites. This novel brachytherapy device efficiently suppressed the growth of the VX2 tumors implanted in the rabbit.