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1.

The use of recombinant gonadotropin-releasing hormone (rGnRH) has very rarely been tested in fish to promote spawning. This study evaluated the impact of recombinant chicken gonadotropin-releasing hormone (rcGnRH) with metoclopramide on the release of sex steroids and final maturation induction in goldfish (Carassius auratus) broodstock. For this purpose, goldfish broodstock was divided into four groups and treated with 0.9% NaCl with 20 mg/kg metoclopramide (Met) (C); 10 μg/kg body weight (BW) rcGnRH with 20 mg/kg metoclopramide (rcGn10); 15 μg/kg BW rcGnRH with 20 mg/kg metoclopramide (rcGn15); and 20 μg/kg BW rcGnRH with 20 mg/kg metoclopramide (rcGn20). The capability of the rcGnRH for eliciting biological response was tested in vivo by evaluating the changes of 17β estradiol (E2), testosterone (T), and 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) and the induced spawning. Blood samples were obtained at 0 h, 12 h, and 24 h after injection. The rcGn10, rcGn15, and rcGn20 treatments induced lower E2 concentration, especially 24 h post-injection. T levels were significantly higher in rcGn10, rcGn15, and rcGn20 treatments 12 h post-injection than at 0 h and then decreased at 24 h post-injection. Furthermore, the rcGnRH tested significantly enhanced DHP secretion in rcGn10, rcGn15, and rcGn20 treatments 12 h post-injection before a decline at 24 h post-injection. No significant difference between the sampling times was found in the C treatment for the 3 sex steroids tested. The results also displayed that rcGnRH at 10–20 µg/kg of body weight can trigger spawning with the highest speed and efficiency of spawning at 20 µg/kg. The obtained results represent a possible strategy for enhancing the artificial reproduction and ovulation of broodstock fish by rGnRH and further support the use of recombinant hormones to promote reproduction in aquaculture.

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2.
Supplements produced by mouse testicular cells (mTCs) and the interaction between cells can increase the differentiation rate of human umbilical cord mesenchymal stem cells (hUCMSCs) into the germ-like cells. We studied the differentiation rate of hUCMSCs into the germ-like cells under effect of mTCs co-culturing. Isolated hUCMSCs from postpartum human umbilical cords were cultured. Then, the expression of mesenchymal (CD73, CD90 and CD105) and haematopoietic (CD34 and CD45) markers of hUCMSCs were confirmed by flow cytometry. Then, the hUCMSCs were cultured in four distinct groups: (a) control, (b) co-culture until D0, (c) co-culture until D5 and (d) co-culture until D10, in order to differentiate into the germ-like cells. After 10 days, the expression of OCT4, VASA, Fragilis and SYCP3 genes were examined by Real-Time qPCR. The flow cytometry indicated a high expression of mesenchymal markers and a low expression of haematopoietic markers (CD73:98.6%, CD90: 99.1%, CD105: 99.5%, CD34: 4.22% and CD45: 2.54%). The expression of OCT4 decreased during the time while the expression of VASA, Fragilis and SYCP3 markers increased in the co-culture with testicular cells (p value <.05). Co-culture with mTCs may be used as an effective method to differentiate hUCMSCs into germ-like cells.  相似文献   
3.
The effect of bacteria inoculation was studied on sunflower growth and phytoremediation capacity in soils contaminated by different levels of nickel. The experimental treatments consisted of four levels of bacteria inoculation – non-inoculated, inoculated by Bacillus safensis, inoculated by Kocuria rosea, and co-inoculated by B. safensis + K. rosea – and four levels of nickel concentrations in the soil – Ni0, Ni150, Ni300, and Ni450 (0, 150, 300, and 450 mg Ni per kg soil, respectively). The treatments were arranged as factorial structure based on a completely randomized design. Results have shown that growth indices, photosynthetic pigments, shoot Fe concentration, root and shoot Zn concentration, and translocation factor decreased as the Ni concentration in soil increased. Shoot and root Ni concentration were higher at Ni450, whereas, the highest Ni uptake by the plant was observed at Ni300 when the sunflower seed was co-inoculated by B. safensis + K. rosea bacteria. Bacteria inoculation significantly increased the plant growth, photosynthetic pigments, and Ni uptake. By B. safensis inoculation, the Fe concentration significantly increased in shoot, while it decreased in root.  相似文献   
4.
The aim of this study was to evaluate the effects of the two types of media, namely minimum essential medium (αMEM) and Ham'sF10, supplemented with foetal bovine serum (FBS) or bovine serum albumin (BSA) in vitrification/warming solution on the quality and viability of sheep ovarian follicles. Vitrification method was applied for cryopreservation of sheep ovarian cortex using Ham'sF10 and αMEM supplemented with either BSA or FBS. There were five groups: Fresh, Ham'sF10+ BSA, Ham'sF10+ FBS, αMEM + BSA and αMEM + FBS. Samples were cultured for two weeks after warming. Viability and morphology of follicles and DNA fragmentation in follicles and in tissue stroma cells were analysed before vitrification/warming and following one and two weeks of culture. The Ham'sF10+ FBS and Ham'sF10+ BSA groups showed a significant decrease in follicular viability after one week of culture (p < .05 vs. Fresh). Following two weeks of culture, all groups revealed a considerable fall in the number of viable follicles (p < .05 vs. Fresh). There was an increase in DNA fragmentation of connective tissue cells but not in the follicles (p < .05). Our results showed the better application of αMEM supplemented with BSA as a vitrification solution in improvement of cryopreservation effects and maintenance of follicular survival.  相似文献   
5.
This paper describes the effect of plant growth-promoting bacteria on sunflower growth and its phytoremediation efficiency under Cd-contaminated soils. Four levels of bacteria inoculation (non-inoculation, inoculation by Bacillus safensis, Kocuria rosea and co-inoculation by Bacillus safensis+Kocuria rosea) and four Cd concentrations (0, 50, 100 and 150 mg Cd per kg soil) were arranged as factorial experiment based on a completely randomized design (CRD). Results showed that Cd significantly decreased growth by decreasing the shoot and root length and biomass (p < 0.01). In addition, Cd dramatically decreases photosynthetic pigments, Fe transport to shoot and Zn uptake (p < 0.01). Bacterial inoculation increased Fe and Zn uptake by plants, Cd concentration in the aboveground part of plants and Cd uptake by the enhancement of Cd concentration in plant tissue and biomass production. Results showed that the highest shoot Cd uptake was ?observed in ?inoculated plants by Bacillus safensis at Cd100 (20.35 mg pot?1). However, in average of Cd treatments, the performance of co-inoculation in Cd uptake (13.04 mg pot?1) was better than singular inoculation (10.68 and 12.58 mg pot?1 for Bacillus safensis and Kocuria rosea, respectively). Results revealed that bacterial inoculation increased the Cd uptake performance in shoot and total biomass by 30% and 25%, respectively.  相似文献   
6.
The objective of this study was to evaluate the efficacy of pre-anesthetic orally administration of clonidine on pulse rate and blood stress response to laryngoscopy and tracheal intubation. In a double-blinded, randomized study, 274 ASA I and II subjects with age of 18 to 45 years scheduled for elective surgery under general anesthesia were enrolled. They were randomly allocated to receive oral clonidine (0.2 mg) or placebo as premedication 90-120 min before surgery. All the patients received Succinylcholine (1.5 mg kg(-1)) after induction of anesthesia with Fentanyl (50 microg) and Thiopentone (5 mg kg(-1)). The anesthesia was maintained with halothane (1.5 Mac) in 50% mixture of N2O/O2. Heart rate and systolic blood pressure were recorded before, immediately after and then every 5 min after intubation until 20 min. The Clonidine group showed a significant superiority over placebo in the prevention of increase in systolic blood pressure as well as heart rate over the intubation. A significant difference was observed in both heart rate and systolic blood pressures were significantly higher in Control group at three subsequent measurements following intubation. The results of this study suggest that orally administered clonidine in preanesthetic period, provides more haemodynamic stability and attenuates the stress response to laryngoscopy and intubation.  相似文献   
7.
Juniperus species （juniper） are resistant to drought and have medicinal properties. In order to investigatethe condition of juniper reproduction and prevent a decline in its area, largely caused by problems in natural regeneration, the asexual reproduction of juniper has received special attention besides its sexual propagation. Among the six species of juniper in Iran, the most abundant are Juniperus polycarpos and J. excelsa. Juniperus polycarpos is ambi-sexual and J. excelsa unisexual. We show that collecting seeds in September provided for better germination than in November. In sexual propagation 82.0% and in asexual （graft） 47.6% success were achieved. Compared to a mixture of water, lime and hormones, a natural treatment of only water had better results. Diurnal change of temperature increased germination of juniper seeds over a constant temperature. Aphyllous stem cuttings from mature and old trees are less successful in rooting than leafy cuttings of juniper saplings. A treatment with Aaterra significantly reduced the percentage of rooted cuttings and total root length. Aliette, Fongarid, Octave, Benomyl, Delsene M and Maneb fungicides significantly increased the percentage of rooted cuttings but did not affect total root length. Autumn explants formed more calli than spring explants. Successful multiplication was achieved by treating buds with a mixture of 0.7% polyvinyl pyrrolidone （PVP） and 2% sucrose and cultured in a basal MS or WRC medium, with a maximum number of new buds. In consideration of extracted material of juniper species in remedy of infectious, fungus, contagious diseases as well as for drought resistance and longevity of this species in severe arid environmental conditions and various industrial applications, reproduction and seed production by micro propagation and biotechnology are necessary.  相似文献   
8.
To determine the effect of adding ketamine to pethidine in reducing post-operative pain in patients undergoing major abdominal operations, in a double blind randomized controlled trial, 100 patients aged 15-60 years who were candidate for elective major abdominal surgery allocated into two groups of pethidine + ketamine group (5 mg pethidine and 0.25 mg kg(-1) ketamine) or pethidine and placebo group (10 mg pethidine and NS) according to the regimen prescribed in postanesthesia care unit. Severity of pain (using visual analogue scale), prescribed dose of pethidine and side effects were recorded until 24 h after operation. Regarding post-operative pain, pethidine + ketamine group showed significant lower scores in all the times except 0 min, 2, 6 and 16 h. Nausea was significantly less frequent amongst pethidine + placebo group at times of 0, 15, 30 and 45 min (p < 0.05). Comparison of two groups did not show significant differences in prescribed pethedine dose in 0, 9, 12, 16, 20 and 24 h (p > 0.05). Yet, the mean dose of administered pethidine as rescue analgesic was significant lower in pethidine + ketamine group compared to pethidine + placebo group (112 +/- 31.5 mg vs. 133.5 +/- 24.5 mg, p < 0.001). In conclusion, our results showed that co-administration of ketamine and pethidine in postanesthesia care unit will improve postoperative pain and reduce narcotic consumption. It may, however, increase rate of postoperative nausea in the first hour after operation.  相似文献   
9.
Twelve multiparous Holstein dairy cows were used in a replicated 4 × 4 Latin square changeover design to evaluate the effects of graded inclusion of soya bean hulls (SHs) in replacement of diet forages at 0%, 10%, 20% and 30% of dietary dry matter (DM) basis on peNDF > 8 and peNDF > 1.18 contents of diets and their resulting effects on chewing activity, nutrient digestibility and milk production of dairy cattle. The control diet contained 50% forage, 50% concentrate and no SH. In the other three diets, SH was substituted for alfalfa hay, corn silage and wheat bran to supply 10%, 20% and 30% of the dietary DM. Increasing SH concentration in the diets resulted in decreasing concentrations of forage neutral detergent fibre (NDF), physically effective NDF (peNDF) and mean particle size (p < 0.01). Chewing activity per kilogram of daily dry matter intake (DMI) was not affected by the different diets tested. However, chewing activity significantly decreased for kilogram intake of NDF, but increased for peNDF > 1.18 when SH was included in the diets (p < 0.01). Total tract apparent digestibility of nutrients significantly increased for DM, organic matter (p < 0.05) and NDF (p < 0.01) but decreased for crude protein (p < 0.05) as the proportion of SH was increased in the diets. Rumen pH value of cattle was not influenced by the diets. Including medium and high amounts of SH in the diets decreased DMI of the animals (p < 0.05) without any significant effect on their daily milk or 4% fat‐corrected milk production. In conclusion, the results of this study showed that the NDF from a non‐forage fibre source like SH had a lower potential for stimulating chewing activity than did forage NDF. Despite this, the small size of dietary particles increased not only the chewing activity per kilogram of peNDF intake but also saliva secretion as well as the potential for rumen to neutralize acids. The findings of this study demonstrate the greater differences in peNDF > 8 among the diets and that these differences are better reflected in terms of DMI, chewing activity and nutrient digestibility, but not in rumen pH.  相似文献   
10.
Genetic Resources and Crop Evolution - Persian walnut (Juglans regia L.) is an economically important species of edible nuts. In the present study, northwest regions of Iran were explored to find...  相似文献   
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