Properties of the amniotic membrane for potential use in tissue engineering

An important component of tissue engineering (TE) is the supporting matrix upon which cells and tissues grow, also known as the scaffold. Scaffolds must easily integrate with host tissue and provide an excellent environment for cell growth and differentiation. Most scaffold materials are naturally derived from mammalian tissues. The amniotic membrane (AM) is considered an important potential source for scaffolding material. The AM represents the innermost layer of the placenta and is composed of a single epithelial layer, a thick basement membrane and an avascular stroma. The special structure and biological viability of the AM allows it to be an ideal candidate for creating scaffolds used in TE. Epithelial cells derived from the AM have the advantages of stem cells, yet are a more suitable source of cells for TE than stem cells. The extracellular matrix components of the basement membrane of the AM create an almost native scaffold for cell seeding in TE. In addition, the AM has other biological properties important for TE, including anti-inflammatory, anti-microbial, anti-fibrosis, anti-scarring, as well as reasonable mechanical property and low immunogenicity. In this review, the various properties of the AM are discussed in light of their potential use for TE

The effect of density and stocking weight on growth rate and production of grey mullet (Mugil cephalus L.)

Around ten thousands fries of Striped grey mullet (Mugil cephalus) with average weight and length of 280 mg and 28.3 mm respectively, imported in March 2008 from Egypt. The wild fries collected from surrounding natural waters of Alexandria. They stocked in four earthen ponds (each with 2500 m2 ) located at the Gomishan shrimp educational centre at late march in 2008. At the first year of culture the densities were 5000 and 10000 individuals per hectare and each treatment with two replicates. At second year, densities changed with 2000 and 2500 individuals per hectares and each of the treatments divided fishes with average primary weights of 80 and 115 grams. They fed twice a day at 8 AM and 2 PM and the amount was 5-7 percents of the fish existent biomass in each ponds. After seven months culture period, the average weight and length of fish in treatment 5000 ind./hec. were 113.7 gr and 21.1 cm respectively and in treatment 10000 ind./hec. the average weight and length were 86.6 gr and 19.6 cm respectively. At first year the average survival rate in different treatments was 77 percent. The average FCR in treatments 5000 and 10000 ind./hec. were 3.4 and 3.9 respectively. At second years after six months culture the average weights in pond no. 9 (with primary weight 115 gr and density 2000 ind./hec) , pond no. 10 (with primary weight 80 gr and density 2000 ind./hec) , pond no. 11 (with primary weight 115 gr and density 2500 ind./hec) and pond no. 12 (with primary weight 80 gr and density 2500 ind./hec) calculated as 476.6 ,338.1, 366.5 and 440 gr respectively. The average survival rate and FCR were 93 % and 3.1 respectively

The effect of lavender essential oil and nanoemulsion on Trichomonas vaginalis in vitro

Background: Trichomonas vaginalis is the cause of trichomoniasis. Due to increased resistance and side effects of the drugs, the aim of this study was to assess an anti-trichomonias effect of lavender (Lavandula officinalis) essential oil and nanoemulsion on T. vaginalis in vitro. Materials and Methods: Lavender essential oil components were characterized by gas chromatography. To determine the cytotoxicity effects, the macrophage cell line J774.A.1 was used. Trichomonas vaginalis was isolated from vaginal secretions of the infected women and then cultured in the TYM complete medium and passaged for 10 days. The effect of essential oil and 1 lavender nanoemulsion in concentrations 10, 25, 50 and 100 μg/mL in the 24-well plate were examined at 1, 2 and 3 hours as triplicate. Positive control was metronidazole (50 μg/mL). The number of live and dead parasites was counted by trypan blue stain with a Neubauer slide. Results: The viability of the macrophages for lavender essential oil was 93.70 and for nanoemulsion was 90.90. Essential oil and nanoemulsion of lavender in concentration of 100 μg/mL and during 3 hours showed 81.7 and 81.9 growth inhibitory, respectively. This difference was not statistically significant. Conclusion: Lavender essential oil and nanoemulsion has a desirable inhibitory effect on growth of T.vaginalis and can be a good choice for conducting therapeutic investigations regarding trichomonial infections

Multiple-breed genomic evaluation by principal component analysis in small size populations

In this study, the effects of breed composition and predictor dimensionality on the accuracy of direct genomic values (DGV) in a multiple breed (MB) cattle population were investigated. A total of 3559 bulls of three breeds were genotyped at 54 001 single nucleotide polymorphisms: 2093 Holstein (H), 749 Brown Swiss (B) and 717 Simmental (S). DGV were calculated using a principal component (PC) approach for either single (SB) or MB scenarios. Moreover, DGV were computed using all SNP genotypes simultaneously with SNPBLUP model as comparison. A total of seven data sets were used: three with a SB each, three with different pairs of breeds (HB, HS and BS), and one with all the three breeds together (HBS), respectively. Editing was performed separately for each scenario. Reference populations differed in breed composition, whereas the validation bulls were the same for all scenarios. The number of SNPs retained after data editing ranged from 36 521 to 41 360. PCs were extracted from actual genotypes. The total number of retained PCs ranged from 4029 to 7284 in Brown Swiss and HBS respectively, reducing the number of predictors by about 85% (from 82% to 89%). In all, three traits were considered: milk, fat and protein yield. Correlations between deregressed proofs and DGV were used to assess prediction accuracy in validation animals. In the SB scenarios, average DGV accuracy did not substantially change when either SNPBLUP or PC were used. Improvement of DGV accuracy were observed for some traits in Brown Swiss, only when MB reference populations and PC approach were used instead of SB-SNPBLUP (+10% HBS, +16%HB for milk yield and +3% HBS and +7% HB for protein yield, respectively). With the exclusion of the abovementioned cases, similar accuracies were observed using MB reference population, under the PC or SNPBLUP models. Random variation owing to sampling effect or size and composition of the reference population may explain the difficulty in finding a defined pattern in the results

Investigation osmoregulation system of the Persian sturgeon released in the Gorgan River

In this study, circumstances of osmoregulation system of the Persian sturgeon released in the Gorgan River in order to stock restoration have been investigated. Ten days old larvae sampled during 45 days from hatchery to the estuary. Samples taken form blood serum, gills and kidney tissues were collected from 12 May to 26 June, 2003. In the present study, Sampling sites were Shahid Marjani sturgeon hatchery, earthen pond, river water (2 sub samples ) and estuary. The blood serum osmotic pressure ( mOsm/L) , K^ + , Na^+, Mg^++ ( mEqu/l) and Ca^++ (mg/dl) concentration were measured. In order to investigate the condition of osmoregulatory cells development, histological experiments of the specific tissues have been taken place accordingly.Regarding to figs. (1,2,3,4,5,6,7,8,9,10) , osmotic pressure of blood plasma was higher than the water ( the difference range is 14- 196 mOsmol/l). Statistical results (test of one way t student) show significant differences between the medium osmotic pressures (P=0.99). In cases of ions, the concentration of Na^+ and K^+ were higher than those of the water. There is also significant difference between these ions concentration (P = 0.01).In contrast, the content of Mg^ ++ and Ca^++ were lower than the water. Regarding to these last two ions, there is also significant difference (P= 0.99). Histological experiments confirm the results and show a relative development of the osmoregulatory cells in gills and kidney in accordance with fish ages

Intra-arterial verapamil improves functional outcomes of thrombectomy in a preclinical model of extended hyperglycemic stroke

The abrupt hyperglycemic reperfusion following thrombectomy has been shown to harm the efficacy of the intervention in stroke patients with large vessel occlusion. Studies of ours and others have shown thioredoxin-interacting protein (TXNIP) is critically involved in hyperglycemic stroke injury. We recently found verapamil ameliorates cerebrovascular toxicity of tissue plasminogen activators in hyperglycemic stroke. The present study aims to answer if verapamil exerts direct neuroprotective effects and alleviates glucose toxicity following thrombectomy in a preclinical model of hyperglycemic stroke. Primary cortical neural (PCN) cultures were exposed to hyperglycemic reperfusion following oxygen-glucose deprivation (OGD), with or without verapamil treatment. In a mouse model of intraluminal stroke, animals were subjected to 4 h middle cerebral artery occlusion (MCAO) and intravenous glucose infusion. Glucose infusion lasted one more hour at reperfusion, along with intra-arterial (i.a.) verapamil infusion. Animals were subjected to sensorimotor function tests and histological analysis of microglial phenotype at 72 h post-stroke. According to our findings, glucose concentrations (2.5–20 mM) directly correlated with TXNIP expression in OGD-exposed PCN cultures. Verapamil (100 nM) effectively improved PCN cell neurite growth and reduced TXNIP expression as well as interaction with NOD-like receptor pyrin domain-containing-3 (NLRP3) inflammasome, as determined by immunoblotting and immunoprecipitation. In our mouse model of extended hyperglycemic MCAO, i.a. verapamil (0.5 mg/kg) could attenuate neurological deficits induced by hyperglycemic stroke. This was associated with reduced microglial pro-inflammatory transition. This finding encourages pertinent studies in hyperglycemic patients undergoing thrombectomy where the robust reperfusion may exacerbate glucose toxicity

Principal component and factor analytic models in international sire evaluation

<p>Abstract</p> <p>Background</p> <p>Interbull is a non-profit organization that provides internationally comparable breeding values for globalized dairy cattle breeding programmes. Due to different trait definitions and models for genetic evaluation between countries, each biological trait is treated as a different trait in each of the participating countries. This yields a genetic covariance matrix of dimension equal to the number of countries which typically involves high genetic correlations between countries. This gives rise to several problems such as over-parameterized models and increased sampling variances, if genetic (co)variance matrices are considered to be unstructured.</p> <p>Methods</p> <p>Principal component (PC) and factor analytic (FA) models allow highly parsimonious representations of the (co)variance matrix compared to the standard multi-trait model and have, therefore, attracted considerable interest for their potential to ease the burden of the estimation process for multiple-trait across country evaluation (MACE). This study evaluated the utility of PC and FA models to estimate variance components and to predict breeding values for MACE for protein yield. This was tested using a dataset comprising Holstein bull evaluations obtained in 2007 from 25 countries.</p> <p>Results</p> <p>In total, 19 principal components or nine factors were needed to explain the genetic variation in the test dataset. Estimates of the genetic parameters under the optimal fit were almost identical for the two approaches. Furthermore, the results were in a good agreement with those obtained from the full rank model and with those provided by Interbull. The estimation time was shortest for models fitting the optimal number of parameters and prolonged when under- or over-parameterized models were applied. Correlations between estimated breeding values (EBV) from the PC19 and PC25 were unity. With few exceptions, correlations between EBV obtained using FA and PC approaches under the optimal fit were ≥ 0.99. For both approaches, EBV correlations decreased when the optimal model and models fitting too few parameters were compared.</p> <p>Conclusions</p> <p>Genetic parameters from the PC and FA approaches were very similar when the optimal number of principal components or factors was fitted. Over-fitting increased estimation time and standard errors of the estimates but did not affect the estimates of genetic correlations or the predictions of breeding values, whereas fitting too few parameters affected bull rankings in different countries.</p

The study of annual cycle of gonads developments and sex steroids of gray mullet, Mugil cephalus in Golestan Province

Grey mullet, Mugil cephalus is one of the most famous and valuable fish on the fisheries and aquaculture industry. This species is the most suitable to introducing the southern, northern and central regions of our country due to high resistant to large variation of water salinity and temperature. On the monthly sampling period biometric data including total length and total weight recorded and length and weight classes for every sex were determined. To understanding of physiological functions and sexual development of reproductive organs, this investigation carried out with Grey mullet imported from Hong Kong by 1993. Findings of this research can be used for management of artificial breeding of this species. Daily variation of pond water temperature was recorded. Sex steroid hormones and other plasma metabolites such as Ca^2+, cholesterol, triglycerides and total proteins were measured by blood sampling. Gonad samples were prepared in order to histological studies. Oocyte growth was studied by measurement of egg diameters. Measured values of cholesterol, triglycerides of blood plasma revealed that these metabolites have seasonal variation and severely deposited on the summer and mobilized on the spawning seasons. Findings of this research suggested that egg diameters, values of sex steroid hormones (estradiol and progesterone) and Calcium concentrations of fish blood plasma shortening increased a long with day length shortening

Study on the reason of striped mullet (Mugil cephalus) larvae mortality and the production of its fingerlings

In this study, nine years old farmed broodstocks of striped grey mullet have been induced artificially by hormones. Eight experiments of artificial propagation carried out during three months (from October to February) in 2003. The hormones used for males were HCG and 17-α-Methyltestosterone and to induce females the hormones such as LHRH-α2, HCG and CPH were used. During these experiments, 27 females injected which 22 of them spawned along with larval production. Water temperature and salinity were 20-23°c and 32 ppt during artificial propagation respectively. For larval culture, two different experiments carried out which final larval density in tanks, water temperature and salinity were 20 in/liter, 22-24°c and 32-33 ppt respectively. Larvae fed with live foods such as Nannochloropsis oculata , Brachionus plicatilis, Artemia nauplii with density of 500000 cell/ml, 20 ind/ml and 3-200 ind/liter respectively. Water exchange in larval culture tanks during first week was 10 percent of tank volume, and this amount in the second and next weeks were higher which have been 2030 and 40-50 percent of tank volume respectively. At the first experiment of larval culture, the tanks with maximum depth of 80 cm used that whole larvae died after 12 days post hatching; whereas at the next trial, three numbers of 4000 liters fiberglass black color tanks with maximum depth of 120 cm used which tend to the survival rate of 0.9 percent after 55 days post hatching

Principal component approach in variance component estimation for international sire evaluation

<p>Abstract</p> <p>Background</p> <p>The dairy cattle breeding industry is a highly globalized business, which needs internationally comparable and reliable breeding values of sires. The international Bull Evaluation Service, Interbull, was established in 1983 to respond to this need. Currently, Interbull performs multiple-trait across country evaluations (MACE) for several traits and breeds in dairy cattle and provides international breeding values to its member countries. Estimating parameters for MACE is challenging since the structure of datasets and conventional use of multiple-trait models easily result in over-parameterized genetic covariance matrices. The number of parameters to be estimated can be reduced by taking into account only the leading principal components of the traits considered. For MACE, this is readily implemented in a random regression model.</p> <p>Methods</p> <p>This article compares two principal component approaches to estimate variance components for MACE using real datasets. The methods tested were a REML approach that directly estimates the genetic principal components (direct PC) and the so-called bottom-up REML approach (bottom-up PC), in which traits are sequentially added to the analysis and the statistically significant genetic principal components are retained. Furthermore, this article evaluates the utility of the bottom-up PC approach to determine the appropriate rank of the (co)variance matrix.</p> <p>Results</p> <p>Our study demonstrates the usefulness of both approaches and shows that they can be applied to large multi-country models considering all concerned countries simultaneously. These strategies can thus replace the current practice of estimating the covariance components required through a series of analyses involving selected subsets of traits. Our results support the importance of using the appropriate rank in the genetic (co)variance matrix. Using too low a rank resulted in biased parameter estimates, whereas too high a rank did not result in bias, but increased standard errors of the estimates and notably the computing time.</p> <p>Conclusions</p> <p>In terms of estimation's accuracy, both principal component approaches performed equally well and permitted the use of more parsimonious models through random regression MACE. The advantage of the bottom-up PC approach is that it does not need any previous knowledge on the rank. However, with a predetermined rank, the direct PC approach needs less computing time than the bottom-up PC.</p