This study investigated the biomass production process from the laboratory to the pilot scale in order to use the nutrient-rich biomass of the diatom Thalassiosira weissflogii as live feed for white-leg shrimp (Litopenaeus vannamei) at larval stages (zoeal, mysis, and postlarval) and in commercial production in hatcheries in Vietnam. Our results showed that T. weissflogii was successfully cultured in 1–2 L Erlenmeyer flasks, 0.2–3.5 m3 composite tanks, and 6.5 m3 tubular photobioreactors, with the highest cell density of 1.6 × 106 cells mL?1 reached after 6 days of culture. Under optimal culture conditions, the protein, lipid, and carbohydrate contents in this algal biomass were 13.2%, 20.0%, and 10.0% of dry cell weight, respectively. The fatty acid composition contains high amount of palmitic acid (C16:0, 43.11% of total fatty acid), and polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA, C20:5ω-3), approximated 16.5% of total fatty acid. In a 50 L larval rearing tank, at the optimal stocking density of 125 nauplii L?1, the survival percentage (75.55%), the total body length (from 5.376 ± 0.007 to 10.860 ± 0.030 mm), and weight (at from PL1 to PL12 stages) (from 0.145 ± 0.002 to 1.158 ± 0.005 g) of the white-leg shrimp larvae reached the highest values but the metamorphosis time (234 h) was shortest compared with the other stocking densities. Further, adding living T. weissflogii biomass to the diet of white-leg shrimp larvae at the nauplii 6 stage led to an increase in the body length, weight, and survival percentage of white-leg shrimp larvae of 21.17%, 35.7%, and 33% higher compared with those of larvae fed the control diet (without the addition of T. weissflogii), respectively. At the same time, the metamorphosis time of larvae (from Z1 to PL1) decreased by 4 h compared to the control group. In intensive ponds (area of 6400 m2 pond?1), using seed stocks at the postlarvae 12 stage that had been fed T. weissflogii, the final weight, yield, and survival percentage of the shrimp were increased by 7.3%, 14.2%, and 16.3%, respectively, compared with those of the control group. There were no statistically significant differences in the protein and carbohydrate contents in the shrimp flesh among the experimental and control group (p > 0.05). The lipid, omega-3, omega-6, and omega-9 fatty acid contents of shrimp flesh in experiment formula (per 100 g shrimp) were 1.21 g, 72.9 mg, 114 mg, and 86.1 mg, 11%, 29%, 21.6%, and 17.7% higher than that those in control, respectively. The obtained results show the great potential of using T. weissflogii as live feed on white-leg shrimp farms in Vietnam.
International Journal of Biometeorology - Epidemiological studies have suggested an association between particulate air pollution, increased temperatures, and morbidity related to pregnancy... 相似文献
Nanocarriers for encapsulation and sustained release of agrochemicals such as auxins have emerged as an attractive strategy to provide enhanced bioavailability and efficacy for improved crop yields and nutrition quality. Here, a comparative study was conducted on the effectiveness of chitosan-as a biopolymeric nanocarrier- and silver-as a metallic nanocarrier- on in vitro adventitious rooting potential of microcuttings in apple rootstocks, for the first time. Auxins indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) loaded silver (nAg) or chitosan nanoparticles (nChi) were synthesized. Scanning electron microscopy and transmission electron microscopy studies showed the spherical shape of the nanoparticles. The average particle size of IAA-nChi was 167.5 ± 0.1 nm while that of IBA-nChi was 123.2 ± 2.6 nm. The hydrodynamic diameter of the nAg-IAA and nAg-IBA particles were measured as 93.66 ± 5 nm and 71.41 ± 3 nm, respectively. Fourier transform infrared spectroscopy analyses confirmed the encapsulation of IAA or IBA in the chitosan nanoparticles. Meanwhile, the characteristic peaks of IAA or IBA were detected on silver nanoparticles. In-vitro adventitious rooting of microcuttings of Malling Merton 106 (MM 106) was significantly higher both in chitosan and silver nanoparticles loaded with IAA or IBA (91.7%–62.5%) compared to free IAA or IBA applications (50.0%–33.3%), except for 2.0 mg L–1 IBA (66.7%). However, the application of 2 mg L–1 IBA and IBA-nChi at all concentrations caused an undesirable large callus development. 相似文献
Therapies that utilize immune checkpoint inhibition work by leveraging mutation-derived neoantigens and have shown greater clinical efficacy in tumors with higher mutational burden. Whether tumors with a low mutational burden are susceptible to neoantigen-targeted therapy has not been fully addressed. To examine the feasibility of neoantigen-specific adoptive T-cell therapy, the authors studied the T-cell response against somatic variants in five patients with myelodysplastic syndrome (MDS), a malignancy with a very low tumor mutational burden. DNA and RNA from tumor (CD34+) and normal (CD3+) cells isolated from the patients’ blood were sequenced to predict patient-specific MDS neopeptides. Neopeptides representing the somatic variants were used to induce and expand autologous T cells ex vivo, and these were systematically tested in killing assays to determine the proportion of neopeptides yielding neoantigen-specific T cells. The authors identified a total of 32 somatic variants (four to eight per patient) and found that 21 (66%) induced a peptide-specific T-cell response and 19 (59%) induced a T-cell response capable of killing autologous tumor cells. Of the 32 somatic variants, 11 (34%) induced a CD4+ response and 11 (34%) induced a CD8+ response that killed the tumor. These results indicate that in vitro induction of neoantigen-specific T cells is feasible for tumors with very low mutational burden and that this approach warrants investigation as a therapeutic option for such patients. 相似文献
The antioxidant and mutagenic/antimutagenic activities of the fixed oils from Nigella sativa (NSO) and Nigella damascena (NDO) seeds, obtained by cold press-extraction from the cultivar samples, were comparatively investigated for the first time. The antimutagenicity test was carried out using classical and modified Ames tests. The fatty acid composition of the fixed oils was characterized by gas chromatography–mass spectrometry (GC-MS) while the quantification of thymoquinone in the fixed oils was determined by UPC2. The main components of the NSO and NDO were found to be linoleic acid, oleic acid, and palmitic acid. The results of the Ames test confirmed the safety of NSO and NDO from the viewpoint of mutagenicity. The results of the three antioxidant test methods were correlated with each other, indicating NDO as having a superior antioxidant activity, when compared to the NSO. Both NSO and NDO exhibited a significant protective effect against the mutagenicity induced by aflatoxin B1 in Salmonella typhimurium TA98 and TA100 strains. When microsomal metabolism was terminated after metabolic activation of the mycotoxin, a significant increase in antimutagenic activity was observed, suggesting that the degradation of aflatoxin B1 epoxides by these oils may be a possible antimutagenic mechanism. It is worthy to note that this is the first study to assess the mutagenicity of NSO and NDO according to the OECD 471 guideline and to investigate antimutagenicity of NDO in comparison to NSO against aflatoxin. 相似文献
BackgroundCoronary ischemia can lead to myocardial damage and necrosis. The pathogenesis of cardiovascular diseases often includes increased oxidative stress and decreased antioxidant defense. The study aimed to assess levels of ischemia modified albumin (IMA), malondialdehyde acid (MDA), superoxide dismutase (SOD), and catalase in individuals diagnosed with ST elevated myocardial infarction (STEMI) and non-STEMI.MethodsThe present study prospectively included 50 STEMI patients, 55 NSTEMI patients, and 55 healthy subjects. Only patients who were recently diagnosed with STEMI or NSTEMI were included in this study. IMA, MDA, SOD, and catalase activities were measured spectrophotometrically. Significant coronary artery lesions were determined by angiography.ResultsPatients with ACS had significantly greater IMA and MDA values than the healthy controls (p<0.001). Besides, patients with STEMI had IMA levels that were significantly greater than those of the patients with NSTEMI (p<0.001), while the reverse was true for MDA levels (p<0.001). The healthy controls had the highest levels of SOD and catalase levels, followed by patients with STEMI and patients with NSTEMI, respectively (p<0.001). There was a significant negative correlation among MDA and SOD with catalase levels (r = -0.771 p<0.001 MDA vs catalase; r = -0.821 p<0.001 SOD vs catalase).ConclusionsData obtained in this study reveals that compared to healthy controls, STEMI and NSTEMI patients had increased levels of MDA and IMA and decreased levels of SOD and catalase. 相似文献
ABSTRACTHeart attack and oxygen deficiency may cause necrosis in the brain and other tissues. We investigated the histopathological effects of nitric oxide (NO) on ischemia/reperfusion in lung and hippocampus using a rat brain bilateral occlusion ischemia model. Male rats were assigned to sham (SH), ischemic preconditioning (PC), global ischemia (GI) and ischemic reperfusion (IR) groups. Before ischemia was induced, blood was drawn to induce hypovolemic hypotension and for blood gas testing. After sacrifice, samples of hippocampus were harvested. Sections were examined using hematoxylin and eosin (H & E) staining and immunostaining using primary antibodies for GFAP, S100β, iNOS, eNOS and the TUNEL method. Following ischemia, we found evidence of gliosis induced oxidative stress and apoptosis in the hippocampus. No significant differences were detected between the SH and PC groups. In the GI and IR groups, apoptosis and necrosis were observed in the hippocampus. Lung sections were stained with H & E and Masson’s trichrome (MT) and immunostained for iNOS and eNOS. The TUNEL method was used to detect apoptosis. Interstitial edema, vascular congestion, intra-alveolar hemorrhage, perivascular edema, neutrophil infiltration and disruption of alveoli were observed after global ischemia and ischemic reperfusion. Inflammatory cells were detected in the connective tissue. The IR and GI groups exhibited significantly more apoptotic cells than the SH or PC groups. Free radicals, such as nitric oxide (NO), that appear following ischemia and reperfusion in the brain may also injure the lungs. Increased NO in both lung and brain tissue suggests that apoptosis in these organs can be induced by reactive nitrogen species. 相似文献
This study was planned to evaluate structural damages in adsorbed vaccines affected by freezing using scanning electron microscopy and X-ray analysis of the elements. Randomly selected 42 vials of eight different types of WHO pre-qualified adsorbed freeze-sensitive vaccines from 10 manufacturers were included in the study. Vaccines were kept at 5 °C. Selected numbers of vials from each type were then exposed to ?25 °C for 24 h periods. All samples were evaluated for their structure using scanning electron microscopy, X-ray analysis of the elements and precipitation time. Scanning electron microscopy of vaccines affected by freezing showed either smooth or rough surfaced conglomerates associated with phosphate content of the precipitate. These vaccines precipitated 2–15 times faster compared to non-frozen samples. Non-frozen samples showed uniform flocculent structure either dense or dispersed. X-ray analysis of precipitates in frozen samples confirmed that the precipitate is mainly aluminium clutters. Scanning electron microscopy confirmed that the lattice structure of bonds between adsorbent and the antigen is broken and aluminium forms conglomerates that grow in size and weight. The precipitation time of vaccines affected by freezing is 4.5 times faster on average compared to non-frozen samples. These facts form the basis of the "shake test". 相似文献