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1.
The present research focused on enhancing the production of wedelolactone through cell suspension culture (CSC) in Eclipta alba (L.) Hassk. With an aim of attaining a sustainable CSC, various plant growth regulators, elicitors and agitation speed were examined. Nodal segments of in vitro propagated plantlets induced the maximum percentage (93.47?±?0.61%) of callus inoculated on Murashige and Skoog (MS) medium fortified with picloram (2 mg L?1). The growth kinetics of CSC exhibited a sigmoid pattern with a lag phase (0–6 days), a log phase (6–18 days), a stationary phase (18–24 days) and then death phase thereafter. The highest biomass accumulation in CSC with 7.09?±?0.06 g 50 mL?1 fresh weight, 1.52?±?0.02 g 50 mL?1 dry cell weight, 1.34?±?0.01?×?106 cell mL?1 total cell count and 57.00?±?0.58% packed cell volume was obtained in the liquid MS medium supplemented with 1.5 mg L?1 picloram plus 0.5 mg L?1 kinetin at 120 rpm. High performance thin layer chromatography confirmed that yeast extract (biotic elicitor) at 150 mg L?1 accumulated more CSC biomass with 1.22-fold increase in wedelolactone (288.97?±?1.94 µg g?1 dry weight) content in comparison to the non-elicited CSC (237.78?±?0.04 µg g?1 dry weight) after 120 h of incubation. Contrastingly, methyl jasmonate (abiotic elicitor) did not alter the biomass but increased the wedelolactone content (259.32?±?1.06 µg g?1 dry weight) to an extent of 1.09-fold at 100 µM. Complete plantlet regeneration from CSC was possible on MS medium containing N6-benzyladenine (0.75 mg L?1) and abscisic acid (0.5 mg L?1). Thus, the establishment of protocol for CSC constitutes the bases for future biotechnological improvement studies in this crop.  相似文献   

2.
Treatment with radionuclide labeled regulatory peptides is a promising tool in the management of patients with inoperable receptor positive neuroendocrine tumors. Peptide receptor lutetium-177 radionuclide therapy currently has gained ample attention due to high specific accumulation of regulatory peptides at tumor cell surface and promising characteristics of β- and γ-energy photons of lutetium-177 radionuclide. In this study gastrin peptides analogues were labeled with lutetium-177 by subsequent mixing of 177LuCl3 (~?185 MBq), ammonium acetate buffer of 5 pH, gentistic acid, aqueous solution of gastrin peptide analogues (1 mg/mL) and heating the reaction mixture at 98 °C which resulted in high radiochemical yield (>?96%). Chromatographic analysis was carried out to analyze the radiochemical purity. The shelf life and serum stability results showed the labeled peptides are sufficiently stable up to 4-h. Glomerular filtration rate study results showed moderate filtration through kidneys. The GFR values of 177Lu-MGCL2 and 177Lu-MGCL4 was noted 48 mL/min and 45 mL/min, respectively. Biodistribution and scintigraphy study using rat and rabbit models showed minimal non-target accumulation, moderate uptake by liver and kidneys. The promising radiochemical yield, stability, GFR values and biodistribution results of 177Lu-MGCL2 & 4 indicate, the agents can be tested clinically for PRRT procedures.  相似文献   

3.
An effective protocol was developed for in vitro regeneration of the Melothria maderaspatana via indirect organogenesis in liquid and solid culture systems. Organogenesis was achieved from liquid culture calluses derived from leaf and petiole explants of mature plants. Organogenic calluses (98.2?±?0.36 and 94.8?±?0.71%) were induced from both leaf and petiole explants on Murashige and Skoog (MS) liquid medium containing 6.0 µM 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.5 µM thidiazuron (TDZ); and 6.0 µM 2,4-D and 1.0 µM benzyladenine (BA) combinations, respectively. Adventitious shoot regeneration (68.2?±?0.06 shoots per explant) was achieved on MS medium supplemented with 2.0 µM BA, 4.0 µM TDZ, 10% v/v coconut water and 0.06 mM glutamine from leaf-derived calluses. Petiole-derived calluses produced adventitious shoots (45.4?±?0.09 shoots per explant) on MS medium fortified with 2.0 µM BA, 4.0 µM TDZ, 10% v/v coconut water, and 0.08 mM glutamine. Elongation of shoots occurred in MS medium with 2.0 µM gibberellic acid (GA3). Regenerated shoots (2–3 cm in length) rooted (74.2?±?0.38%) and hardened (85?±?1.24%) when they were transferred to 1/2-MS medium supplemented with 3.0 µM indole-3-butyric acid (IBA) followed by garden soil, vermiculate, and sand (2:1:1 ratio) mixture. The elongated shoots (4–5 cm in length) were exposed simultaneously for rooting as well as hardening (100%) in moistened [(1/8-MS basal salt solution with 5 µM IBA and 100 mg l?1 Bavistin® (BVN)] garden soil, vermiculate, and sand (2:1:1 ratio) mixture. Subsequently, the plants were successfully established in the field. The survival percentage differed with seasonal variations.  相似文献   

4.
This paper presents results of 131I air activity measurements performed within nuclear medical hospitals as a tool for internal dose assessment. The study was conducted at a place of preparation and administration of 131I (“hot room”) and at a nurse station. 131I activity measurements were performed for 5 and 4 consecutive working days, at the “hot room” and nurse station, respectively. Iodine from the air was collected by a mobile HVS-30 aerosol sampler combined with a gas sampler. Both the gaseous and aerosol fractions were measurement. The activities in the gaseous fraction ranged from (28?±?1 Bq m?3) to (492?±?4) Bq m?3. At both sampling sites, the activity of the gaseous iodine fraction trapped on activated charcoal was significantly higher than that of the aerosol fraction captured on Petrianov filter cloth. Based on these results, an attempt has been made to estimate annual inhalation effective doses, which were found to range from 0.47 mSv (nurse female) to 1.3 mSv (technician male). The highest annual inhalation equivalent doses have been found for thyroid as 32, 27, 13, and 11 mSv, respectively, for technician male, technical female, nurse male, and nurse female. The method presented here allows to fill the gaps in internal doses measurements. Moreover, because method has been successful used for many years in radioactive contamination monitoring of air in cases of serious nuclear accidents, it should also be used in nuclear medicine.  相似文献   

5.
This study aimed to overexpress a glucose oxidase gene (GOD1) in Aureobasidium sp. P6 to achieve Ca2+-gluconic acid (GA) overproduction. The GOD1 gene was cloned, deleted, and overexpressed. A protein deduced from the GOD1 gene of Aureobasidium sp. P6 strain had 1824 bp that encoded a protein with 606 amino acids, with a conserved NADB-ROSSMAN domain and a GMC-oxred domain. Deleting the GOD1 gene made the disruptant GOK1 completely lose the ability to produce GA and GOD1 activity, whereas overexpressing the GOD1 gene rendered the transformant GOEX8 to produce considerably more Ca2+-GA (160.5?±?5.6 g/L) and higher GOD1 activity (1438.6?±?73.2 U/mg of protein) than its parent P6 strain (118.7?±?4.3 g/L of Ca2+-GA and 1100.0?±?23.6 U/mg of GOD1 protein). During a 10-L fermentation, the transformant GOEX8 grown in the medium containing 160.0 g/L of glucose produced 186.8?±?6.0 g/L of Ca2+-GA, the yield was 1.2 g/g of glucose, and the volumetric productivity was 1.7 g/L/h. Most of the produced GOD1 were located in the yeast cell wall. The purified product was identified to be a GA. The transformant GOEX8 overexpressing the GOD1 gene could produce considerably more Ca2+-GA (186.8?±?6.0 g/L) than its wild-type strain P6.  相似文献   

6.
The current study aimed to develop a prolonged-release pramipexole (PPX) transdermal patch for the treatment of Parkinson’s disease. Permeation parameters of PPX were investigated using human cadaver skin. Pramipexole patches were prepared using DURO-TAK® pressure-sensitive-adhesive (PSA) and evaluated for drug stability, drug loading, in vitro drug release, and in vitro permeation through mouse skin. The results indicated that blends of DURO-TAK® 87-2852 and DURO-TAK® 87-2510 were suitable for creating a prolonged-release PPX patch due to their advantages in drug release, drug loading, and stability. The final formulation consisted of 87-2852/87-2510 (70:30), 10% PG, and 15% PPX and showed a cumulative permeation amount of 1497.19?±?102.90 μg/cm2 with a continuous flux over 6.0 μg/(cm2·h) across human cadaver skin for 7 days. In vivo studies in rats indicated that PPX patch produced a significantly longer (p?<?0.001) half-life (t 1/2, 75.16?±?17.37 h) and mean residence time (MRT, 135.89?±?24.12 h) relative to oral tablets (Sifrol®) and had a relative bioavailability of 51.64?±?21.32%. Therefore, this study demonstrated the feasibility of developing a prolonged-release PPX patch, which proposed the potential to serve as an alternate to conventional oral tablets and may therefore improve patient compliance.  相似文献   

7.

Introduction

The analysis of limited-quantity samples remains a challenge associated with mouse models, especially for multi-platform metabolomics studies. Although inherently insensitive, the highly specific characteristics of nuclear magnetic resonance (NMR) spectroscopy make it an advantageous platform for global metabolite profiling, particularly in mitochondrial disease research.

Objectives

Show method equivalency between a well-established standard operating protocol (SOP) and our novel miniaturized 1H-NMR method.

Method

The miniaturized method was performed in a 2 mm NMR tube on a standard 500 MHz NMR spectrometer with a 5 mm triple-resonance inverse TXI probe at room temperature.

Results

Firstly, using synthetic urine spiked with low (50 µM), medium (250 µM) and high (500 µM) levels (n?=?10) of nine standards, both the SOP and miniaturized method were shown to have acceptable precision (CV?<?15%), relative accuracy (80–120%), and linearity (R2?>?0.95), except for taurine. Furthermore, statistical equivalence was shown using the two one-sided test. Secondly, pooled mouse quadriceps muscle extract was used to further confirm method equivalence (n?=?3), as well as explore the analytical dynamics of this novel approach by analyzing more-concentrated versions of samples (up to 10× concentration) to expand identification of metabolites qualitatively, with quantitative linearity. Lastly, we demonstrate the new technique’s application in a pilot metabolomics study using minute soleus muscle tissue from a mouse model of Leigh syndrome using Ndufs4 KO mice.

Conclusion

We demonstrate method equivalency, supporting our novel miniaturized 1H-NMR method as a financially feasible alternative to cryoprobe technology—for limited-quantity biological samples in metabolomics studies that requires a volume one-tenth of the SOP.
  相似文献   

8.
Protein conformational changes play crucial roles in enabling function. The Carr–Purcell–Meiboom–Gill (CPMG) experiment forms the basis for studying such dynamics when they involve the interconversion between highly populated and sparsely formed states, the latter having lifetimes ranging from ~?0.5 to ~?5 ms. Among the suite of experiments that have been developed are those that exploit methyl group probes by recording methyl 1H single quantum (Tugarinov and Kay in J Am Chem Soc 129:9514–9521, 2007) and triple quantum (Yuwen et al. in Angew Chem Int Ed Engl 55:11490–11494, 2016) relaxation dispersion profiles. Here we build upon these by developing a third experiment in which methyl 1H double quantum coherences evolve during a CPMG relaxation element. By fitting single, double, and triple quantum datasets, akin to recording the single quantum dataset at static magnetic fields of Bo, 2Bo and 3Bo, we show that accurate exchange values can be obtained even in cases where exchange rates exceed 10,000 s?1. The utility of the double quantum experiment is demonstrated with a pair of cavity mutants of T4 lysozyme (T4L) with ground and excited states interchanged and with exchange rates differing by fourfold (~?900 s?1 and ~?3600 s?1), as well as with a fast-folding domain where the unfolded state lifetime is ~?80 µs.  相似文献   

9.
Successful commercialization of microbial biocontrol agents, such as Metarhizium spp., is often constrained by poor drying survival and shelf life. Here, we hypothesized that culture age would influence endogenous arabitol, erythritol, mannitol and trehalose contents in M. brunneum mycelium and that elevated levels of these compounds would improve drying survival and shelf life of encapsulated mycelium coupled with enhanced fungal virulence against T. molitor larvae. We found that culture age significantly influenced endogenous arabitol and mannitol contents in mycelium with highest concentrations of 0.6?±?0.2 and 2.1?±?0.2 µg/mg after 72 h, respectively. Drying survival of encapsulated mycelium was independent of culture age and polyol content with 41.1?±?4.4 to 55.0?±?6.2%. Best shelf life was determined for biomass harvested after 72 h at all investigated storage temperatures with maximum values of 59.5?±?3.3% at 5 °C followed by 54.5?±?1.6% at 18 °C and 19.4?±?1.3% at 25 °C after 6 months. Finally, high fungal virulence against T. molitor larvae of 83.3?±?7.6 to 98.0?±?1.8% was maintained during storage of encapsulated mycelium for 12 months with larval mortalities being independent of culture age and polyol content. In conclusion, our findings indicate beneficial effects of endogenous polyols in improving shelf life of encapsulated mycelium and this may spur the successful development of microbial biocontrol agents in the future.  相似文献   

10.
Postoperative 131I treatment for differentiated thyroid cancer (DTC) can create a radiation hazard for nearby persons. The present prospective study aimed to investigate radiation dose rates in 131I-treated DTC patients to provide references for radiation protection. A total of 141 131I-treated DTC patients were enrolled, and grouped into a singular treatment (ST) group and a repeated treatment (RT) group. The radiation dose rate of 131I-treated patients was measured. The rate of achieving discharge compliance and restricted contact time were analyzed based on Chinese regulations. Multivariate logistic regression analysis was used to analyze the independent factors associated with the clearance of radioiodine. The rate of achieving discharge compliance (131I retention <?400 MBq) was 79.8 and 93.7% at day 2 (D2) for the ST and RT groups, respectively, and reached 100% at D7 and D4, respectively. The restricted contact time with 131I-treated patients at 0.5 m for medical staff, caregivers, family members, and the general public ranged from 4 to 7 days. Multivariate logistic regression analysis showed that the 24-h iodine uptake rate was the only significant factor associated with radioiodine clearance. For the radiation safety of 131I-treated DTC patients, the present results can provide radiometric data for radiation protection.  相似文献   

11.
We investigated the pharmacological actions of a slow-releasing H2S donor, GYY 4137; a substrate for the biosynthesis of H2S, l-cysteine and its precursor, N-acetylcysteine on potassium (K+; 50 mM)-evoked [3H]D-aspartate release from bovine isolated retinae using the Superfusion Method. GYY 4137 (10 nM–10 µM), l-cysteine (100 nM–10 µM) and N-acetylcysteine (10 µM–1 mM) elicited a concentration-dependent decrease in K+-evoked [3H]D-aspartate release from isolated bovine retinae without affecting basal tritium efflux. At equimolar concentration of 10 µM, the rank order of activity was as follows: l-cysteine?>?GYY 4137?>?N-acetylcysteine. A dual inhibitor of the biosynthetic enzymes for H2S, cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE), amino-oxyacetic acid (AOA; 3 mM) reversed the inhibitory responses caused by GYY 4137, l-cysteine and N-acetylcysteine on K+-evoked [3H]D-aspartate release. Glibenclamide (300 µM), an inhibitor of KATP channels blocked the inhibitory action of GYY 4137 and l-cysteine but not that elicited by N-acetylcysteine on K+-induced [3H]D-aspartate release. The inhibitory effect of GYY 4137 and l-cysteine on K+-evoked [3H]D-aspartate release was reversed by the non-specific inhibitor of nitric oxide synthase (NOS), l-NAME (300 µM). Furthermore, a specific inhibitor of inducible NOS (iNOS), aminoguanidine (10 µM) blocked the inhibitory action of l-cysteine on K+-evoked [3H]D-aspartate release. We conclude that both donors and substrates for H2S production can inhibit amino acid neurotransmission in bovine isolated retinae, an effect that is dependent, at least in part, upon the intramural biosynthesis of this gas, and on the activity of KATP channels and NO synthase.  相似文献   

12.
A general method for calculating doses absorbed from isotopes released in nuclear accidents is presented. As an example, this method was used to calculate doses for inhabitants of Southern Poland due to inhalation of 131I released due to the Fukushima nuclear plant accident. 131I activity measurements in the air of that region provided the basis for the study. The proposed model is based on a complex biokinetic model for iodine merging the Leggett model developed in 2010 with the human respiratory tract and gastrointestinal tract models recommended by the International Commission on Radiological Protection (ICRP). This model is described here, and it is demonstrated that resulting dose estimates are consistent with those obtained using the ICRP methodology. Using the developed model, total doses were calculated for six age groups of both genders, for gaseous and aerosol fractions alike. The committed effective dose, H 50, for an adult man reached 16 nSv, which is lower than 0.001% of the background dose. The dose for the thyroid of an adult reached 0.33 μSv, which corresponds to circa 0.0007% of the dose to the population of Southern Poland after the Chernobyl nuclear plant accident.  相似文献   

13.
The present study reports the in vitro biological nature of the pigment produced by Staphylococcus gallinarum KX912244, isolated as the gut microflora bacterium of the insect Bombyx mori. The purified pigment was characterized as Staphyloxanthin based on bio-physical characterization techniques like Fourier transform infrared spectroscopy, high performance liquid chromatography, Proton nuclear magnetic resonance spectroscopy (1H NMR), Liquid chromatography-Mass spectroscopy and Gas chromatography-Mass spectroscopy. The Staphyloxanthin pigment presented considerable biological properties including in vitro antimicrobial activity against pathogens Staphylococcus aureus, Escherichia coli and Candida albicans; in vitro antioxidant activity by % DPPH free radical scavenging activity showing IC50 value of 54.22 µg/mL; DNA damage protection activity against reactive oxygen species and anticancer activity evaluated by cytotoxicity assay against 4 different cancer cell lines like the Dalton’s lymphoma ascites with IC50 value 6.20?±?0.02 µg/mL, Ehrlich ascites carcinoma having IC50 value 6.48?±?0.15 µg/mL, Adenocarcinomic human alveolar basal epithelial cells (A549 Lung carcinoma) bearing IC50 value 7.23?±?0.11 µg/mL and Mus mucus skin melanoma (B16F10) showing IC50 value 6.58?±?0.38 µg/mL and less cytotoxicity towards non-cancerous human fibroblast cell lines (NIH3T3) with IC50 value of 52.24 µg/mL. The present study results suggest that Staphyloxanthin acts as a potential therapeutic agent especially due to its anticancer property.  相似文献   

14.
The land crab Cardisoma guanhumi is one of the most common species in mangroves of the American Atlantic coast and Caribbean islands however, studies of its effects on the physical and chemical soil properties are scarce. This study compares specific physicochemical properties of soil between C. guanhumi burrows (B) and adjacent zones (AZ), and provides the first insights on their role as an ecosystem engineer in mangroves. The study was conducted in an estuarine system dominated by Rhizophora mangle, located at the Río Chico estuary, Miranda state of Venezuela. Random soil samples were taken digging each burrow until reaching the bottom and at the same depth for AZ. Data analysis was carried out using Bayesian inference. Credible mean differences between B and AZ, were found for sand (B?=?26.53?±?10.76, AZ?=?17.25?±?5.7%), silt (B?=?73.16?±?10.77, AZ?=?82.42?±?5.69%), pH (B?=?8.71?±?0.36, AZ?=?9.12?±?0.30), soil organic matter (SOM, B?=?0.43?±?0.21, AZ?=?0.17?±?0.06%), total N (TN, B?=?786?±?232, AZ?=?529?±?107 µg g?1), Mg (B?=?4.42?±?0.60, AZ?=?3.48?±?0.71 cmolc kg?1) and K (B?=?0.12?±?0.05 AZ?=?0.06?±?0.02 cmolc kg?1). Chemical variables as SOM, K, Mg and TN showed the highest values of effect size (>?1.4). With the exception of the pH, all chemicals variables—which were different between B and AZ—showed strong and decisive evidences of correlations with SOM. When SOM variable was controlled, the relationships between pH–TN, TN–K and Mg–K decreased, even though the correlation evidence between each pair remained. Differences in chemical contents found in B respect to AZ suggest that the activities of C. guanhumi (feeding, moulting, excretion and defecation) within their burrows promote the spatial heterogeneity of mangrove soils.  相似文献   

15.
The influence of light quality and cytokinin content in media on growth, development, photosynthetic pigments and secondary metabolite content of Myrtus communis L. was evaluated in an in vitro culture. Various treatments with light emitting diodes (LEDs): 100% blue (B), a mix of 70% red and 30% blue (RB) and 100% red were applied and compared with a traditional fluorescent lamp as control. Axillary shoots were incubated on Murashige and Skoog medium with 30 g dm?3 sucrose, 0.5% BioAgar, 0.5 μM 1-naphthaleneacetic acid and different concentrations of 6-benzyladenine (BA): 1, 2.5 and 5 µM. Cultures were maintained for 6 weeks in 23/21?±?1 °C (day/night), 80% relative humidity and 16/8 h photoperiod; photosynthetic photon flux density (PPFD) was 35 µmol m?2 s?1 in all treatments. Light spectra and BA content in media affected biometrical and phytochemical M. communis properties. Red LEDs and 5 µM BA resulted in the highest multiplication rate. The highest shoots were obtained under red LEDs, but with the lowest concentration of cytokinin in media. Fresh weight was greatest on LEDs containing blue light in the spectrum (B and RB); moreover, 5 µM BA increased dry weight. Photosynthetic pigment levels were lower under LED light compared to control lamps. Phenolic acids and flavonoids were identified in M. communis leaf extracts. Myricetin was the major constituent with highest concentration under red LEDs and highest BA level.  相似文献   

16.
In order to induce the direct formation of erect dark brown vegetative shoots of Kappahycus alvarezii, under micro-propagation conditions, the agricultural bio-stimulant “Acadian Marine Plant Extract Powder” (or AMPEP) K+ (a Canadian commercial extract of the brown seaweed Ascophyllum nodosum with enhanced levels of potassium) was used singly or in combination with colchicine or oryzalin at different concentrations plus (synthetic) plant growth regulators (i.e., PGR, IAA, and kinetin) over 45 days of incubation. Amongst the treatments tested, 5 mg L?1 AMPEP K+ with PGR produced the longest direct axis shoots (9.6 ± 0.33 mm), followed by 0.1 mg L?1 AMPEP K+ + 1.0 mg L?1 oryzalin with PGR (8.7 ± 0.00 mm), 10 mg L?1 AMPEP K+ + 0.5 mg L?1 colchicine with PGR (8.6 ± 1.20 mm), and 0.5 mg AMPEP K+ only (5.3 ± 1.8 mm). The shortest, direct axis shoots measured were the following: 8.3 ± 0.33 mm with 0.1, 1 and 10 mg L?1 AMPEP K+ with PGR, 6.0 ± 0.58 mm with 0.5 mg L?1 AMPEP K+ + 0.1 mg L?1 oryzalin with PGR, 5.3 ± 0.89 mm with 0.5 mg L?1 AMPEP K+ + 0.1 mg L?1 colchicine with PGR, and finally, 2.7 ± 0.33 mm with 0.1 mg L?1 AMPEP K+ only. The percentage of direct shoots formed ranged from 93 to 100 % and 87 to 100 % in AMPEP K+ with PGR and AMPEP K+ only, respectively, while 62–100 % and 87–100 % were observed in AMPEP K+ + colchicine with PGR and AMPEP K+ + oryzalin with PGR, respectively. The use of AMPEP K+ with the PGR resulted in the longest and highest percentage formation of direct axis shoots. These observations, taken together, suggested the efficacy of AMPEP K+ used as a protocol to induce direct, erect shoots for the micro-propagation of K. alvarezii plantlets under laboratory conditions.  相似文献   

17.
Electrophysiological effects produced by selective activation of M3 cholinoreceptors were studied in isolated left atrium preparations from rat using the standard sharp glass microelectrode technique. The stimulation of M3 receptors was obtained by application of muscarinic agonist pilocarpine (10?5 M) in the presence of selective M2 antagonist methoctramine (10?7 M). Stimulation of M3 receptors induced marked reduction of action potential duration by 14.4 ± 2.4% and 16.1 ± 2.5% of control duration measured at 50 and 90% of repolarization, respectively. This effect was completely abolished by selective M3 blocker 4-DAMP (10?8 M). In isolated myocytes obtained from the rat left atrium, similar pharmacological stimulation of M3 receptors led to suppression of peak L-type calcium current by 13.9 ± 2.6% of control amplitude (measured at +10 mV), but failed to affect K+ currents I to, I Kur, and I Kir. In the absence of M2 blocker methoctramine, pilocarpine (10?5 M) produced stronger attenuation of I CaL and induced an increase in I Kir. This additive inward rectifier current could be abolished by highly selective blocker of Kir3.1/3.4 channels tertiapin-Q (10?6 M) and therefore was identified as I KACh. Thus, in the rat atrial myocardium activation of M3 receptors leads to shortening of action potentials via suppression of I CaL, but does not enhance the major potassium currents involved in repolarization. Joint stimulation of M2 and M3 receptors produces stronger action potential shortening due to M2-mediated activation of I KACh.  相似文献   

18.
The present work evaluated biomass productivity, carbon dioxide fixation rate, and biochemical composition of two microalgal species, Phaeodactylum tricornutum (Bacillariophyta) and Tetradesmus obliquus (Chlorophyta), cultivated indoors in high-technology photobioreactors (HT-PBR) and outdoors both in pilot ponds and low-technology photobioreactors in a greenhouse in southern Italy. Microalgae were grown in standard media, under nitrogen starvation, and in two liquid digestates obtained from anaerobic digestion of agro-zootechnical and vegetable biomass. P. tricornutum, cultivated in semi-continuous mode in indoor HT-PBRs with standard medium, showed a biomass productivity of 21.0?±?2.3 g m?2 d?1. Applying nitrogen starvation, the lipid productivity increased from 2.3 up to 4.5?±?0.5 g m?2 d?1, with a 24 % decrease of biomass productivity. For T. obliquus, a biomass productivity of 9.1?±?0.9 g m?2 d?1 in indoor HT-PBR was obtained using standard medium. Applying liquid digestates as fertilizers in open ponds, T. obliquus gave a biomass productivity (10.8?±?2.0 g m?2 d?1) not statistically different from complete medium such as P. tricornutum (6.5?±?2.2 g m?2 d?1). The biochemical data showed that the fatty acid composition of the microalgal biomass was affected by the different cultivation conditions for both microalgae. In conclusion, it was found that the microalgal productivity in standard medium was about doubled in HT-PBR compared to open ponds for P. tricornutum and was about 20 % higher for T. obliquus.  相似文献   

19.
The genetic manipulation of Capsicum has been unsuccessful, and a large bottleneck to transferring the desired genes is due to the difficulty in regenerating whole plants through tissue culture because of its highly recalcitrant and high genotype specificity. This study aimed to investigate and establish rapid shoot regeneration from the proximal ends of the leaves of Capsicum frutescens KT-OC and BOX-RUB varieties. A maximum of 8–10 shoot buds were obtained from the margins of the proximal portion of a cotyledonary leaf explant of C. frutescens variety KT-OC on medium I containing 44.44 µM 6-benzylaminopurine (BA), 5.71 µM indole-3-acetic acid (IAA), 10 µM silver nitrate (AgNO3) and 1.98 mg L?1 2-(N-morpholine) ethane sulphonic acid within 4 weeks of incubation, of which 60% of explants responded in terms of shoot buds. Petiole explants (40%) cultured on the same medium produced 2–4 shoots per explant from the distal portion. The cut portions of the cotyledonary leaf proximal portions responded well to shoot bud formation in the presence of 22.20 µM BA and 14.68 µM phenyl acetic acid (PAA), wherein 100% of explants responded in terms of shoot bud formation, with an average of 10?±?1.7 and 8?±?1.9 shoot buds per explant in KT-OC and BOX-RUB varieties, respectively. The differentiated shoots grew well and proliferated in the presence of 14.68 µM PAA?+?22.20 µM BA and 10 µM AgNO3. Shoot elongation was obtained in presence of 1.44 µM gibberellic acid (GA3) and 10 µM AgNO3. These shoots were rooted on plant growth regulator-free half-strength MS medium and upon hardening; field survival rate was 70%. This reproducible regeneration method for C. frutescens, especially the Indian high pungent variety, from proximal portion of cotyledonary leaf and petiole explants, can be used for biotechnological improvement.  相似文献   

20.
The objective of the present work is to apply the plasma clearance parameters to strontium, previously determined in our laboratory, to improve the biokinetic and dosimetric models of strontium-90 (90Sr) used in radiological protection; and also to apply this data for the estimation of the radiation doses from strontium-89 (89Sr) after administration to patients for the treatment of the painful bone metastases. Plasma clearance and urinary excretion of stable strontium tracers of strontium-84 (84Sr) and strontium-86 (86Sr) were measured in GSF-National Research Center for Environment and Health (GSF) in 13 healthy German adult subjects after intravenous injection and oral administration. The biological half-life of strontium in plasma was evaluated from 49 plasma concentration data sets following intravenous injections. This value was used to determine the transfer rates from plasma to other organs and tissues. At the same time, the long-term retention of strontium in soft tissue and whole body was constrained to be consistent with measured values available. A physiological urinary path was integrated into the biokinetic model of strontium. Parameters were estimated using our own measured urinary excretion values. Retention and excretion of strontium were modeled using compartmental transfer rates published by the International Commission on Radiological Protection (ICRP), the SENES Oak Ridge Inc. (SENES), and the Urals Research Center for Radiation Medicine (TBM). The results were compared with values calculated by applying our GSF parameters (GSF). For the dose estimation of 89Sr, a bone metastases model (GSF-M) was developed by adding a compartment, representing the metastases, into the strontium biokinetic model. The related parameters were evaluated based on measured data available in the literature. A set of biokinetic parameters was optimized to represent not only the early plasma kinetics of strontium but also the long-term retention measured in soft tissue and whole body. The ingestion dose coefficients of 90Sr were computed and compared with different biokinetic model parameters. The ingestion dose coefficients were calculated as 2.8 × 10−8, 2.1 × 10−8, 2.5 × 10−8 and 3.8 × 10−8 Sv Bq−1 for ICRP, SENES, TBM and GSF model parameters, respectively. Moreover, organ absorbed dose for the radiopharmaceutical of 89Sr in bone metastases therapy was estimated based on the GSF and ICRP biokinetic model parameters. The effective doses were 3.3, 1.8 and 1.2 mSv MBq−1 by GSF, GSF-M, and ICRP Publication 67 model parameters, respectively, compared to the value of 3.1 mSv MBq−1 reported by ICRP Publication 80. The absorbed doses of red bone marrow and bone surface, 17 and 21 mGy MBq−1 calculated by GSF parameters, and 7.1 and 8.8 mGy MBq−1 by GSF-M parameters, are comparable to the clinical results of 3–19 mGy MBq−1 for bone marrow and 16 mGy MBq−1 for bone surface. Based on the GSF-M model, the absorbed dose of 89Sr to metastases was estimated to be 434 mGy MBq−1. The strontium clearance half-life of 0.25 h from the plasma obtained in the present study is obviously faster than the value of 1.1 h recommended by ICRP. There are no significant changes for ingestion dose coefficients of 90Sr using different model parameters. A model including the metastases was particularly developed for dose estimation of 89Sr treatment for the pain of bone metastases.  相似文献   

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