Hip joint replacement surgery for idiopathic osteoarthritis aggregates in families

In order to determine whether there is a genetic component to hip or knee joint failure due to idiopathic osteoarthritis (OA), we invited patients (probands) undergoing hip or knee arthroplasty for management of idiopathic OA to provide detailed family histories regarding the prevalence of idiopathic OA requiring joint replacement in their siblings. We also invited their spouses to provide detailed family histories about their siblings to serve as a control group. In the probands, we confirmed the diagnosis of idiopathic OA using American College of Rheumatology criteria. The cohorts included the siblings of 635 probands undergoing total hip replacement, the siblings of 486 probands undergoing total knee replacement, and the siblings of 787 spouses. We compared the prevalence of arthroplasty for idiopathic OA among the siblings of the probands with that among the siblings of the spouses, and we used logistic regression to identify independent risk factors for hip and knee arthroplasty in the siblings. Familial aggregation for hip arthroplasty, but not for knee arthroplasty, was observed after controlling for age and sex, suggesting a genetic contribution to end-stage hip OA but not to end-stage knee OA. We conclude that attempts to identify genes that predispose to idiopathic OA resulting in joint failure are more likely to be successful in patients with hip OA than in those with knee OA.     

Rapid evolution of immunoglobulin superfamily C2 domains expressed in immune system cells

To test the hypothesis that proteins expressed in cells of the vertebrate immune system evolve unusually rapidly, 107 orthologous immunoglobulin C2 domains were compared between human and murine rodent. The analysis showed that the rate of nonsynonymous (amino-acid- altering) nucleotide substitution in these domains was correlated with factors associated with protein structure and with breadth of tissue expression, as well as with the rate of synonymous substitution. However, when such factors were controlled for statistically, there remained a strong positive association between expression in the immune system and nonsynonymous rate, with the highest rates being seen in genes expressed in the immune system only. Certain immune system genes are known to be subject to positive selection favoring diversity at the amino acid level; most of these genes encode receptors that interact directly with foreign antigens. The observed acceleration of the rate of nonsynonymous evolution in C2 domains of immune system proteins may be explained by either (1) reduced constraint at the amino acid level on molecules interacting with immune system receptors that are themselves evolving rapidly due to positive diversifying selection or (2) positive selection favoring amino acid changes correlated with changes in the immune system receptors.      

Position specific growth regulation of 3T3 cells in vivo.

In this study we have investigated the mechanism by which spatial growth is regulated by monitoring 3T3 cells, introduced into the developing mouse limb using exo utero surgery. The 3T3 cells were labeled with a human cell surface glycoprotein, CD8, and injected into stage 7-9 mouse limbs. At 24 and 48 hr after injection embryos were labeled with [3H]thymidine and processed for immunohistochemistry and autoradiography. The labeling index of CD8 positive cells was compared to that of neighboring limb bud cells and also to the position of the injection site within the limb. We find that the labeling index of 3T3 cells is in accord with that of the limb cells that immediately surround them; 3T3 cells display a high labeling index in limb regions of high growth and a low labeling index in limb regions of low growth. In addition, we find that both limb bud cells and injected 3T3 cells display a general proximal (low) to distal (high) gradient of growth at the stages analyzed. We conclude from these results that position-specific regulation of growth occurs in a non-cell autonomous manner and is likely to be mediated by mitogenic signals that are localized within the limb environment. In addition, our results demonstrate the usefulness of utilizing established cell lines as in vivo probes to monitor developmental mechanisms.     

Motoneurons purified by cell sorting respond to two distinct activities in myotube-conditioned medium

Spinal motoneurons from chick embryos were purified by retrograde transport and fluorescence-activated cell sorting. Growth conditions for motoneurons were studied, with experiments focused on the effects of conditioned media from chick myotubes, fibroblasts, and spinal cord dividing cells. Motoneurons rapidly extended neurites when plated onto polylysine-coated dishes that had been exposed to these conditioned media. Enzymatic analysis of the substratum-binding, neurite outgrowth-promoting activity from myotube-conditioned medium indicated that it contained heparan sulfate and protein. The neurite outgrowth-promoting activity sedimented as a peak centered at a density of 1.34 in associative cesium chloride gradients, and eluted near the void volume of a Sepharose CL-6B column. Inclusion of myotube conditioned medium in the culture medium of motoneurons also enhanced their survival over periods greater than 2 days in culture. This enhancement of survival could not be explained by myotube-conditioned medium providing motoneurons with a continuous supply of the neurite outgrowth-promoting activity. Media conditioned by spinal cord dividing cells and fibroblasts supported motoneuron survival to some extent, but this effect was not as great as that of myotube-conditioned medium.     

Genotype × environment interaction in the allometry of body,genitalia and signal traits in Enchenopa treehoppers (Hemiptera: Membracidae)

Developmental plasticity may promote divergence by exposing genetic variation to selection in novel ways in new environments. We tested for this effect in the static allometry (i.e. scaling on body size) of traits in advertisement signals, body and genitalia. We used a member of the Enchenopa binotata species complex of treehoppers – a clade of plant‐feeding insects in which speciation is associated with colonization of novel environments involving marked divergence in signals, subtle divergence in body size and shape, and no apparent divergence in genitalia. We found no change in mean allometric slopes across environments, but substantial genetic variation and genotype × environment interaction (G × E) in allometry. The allometry of signal traits showed the most genetic variation and G × E, and that of genitalia showed the weakest G × E. Our findings suggest that colonizing novel environments may have stronger diversifying consequences for signal allometry than for genitalia allometry. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 187–196.     

Localisation of the SMC loading complex Nipbl/Mau2 during mammalian meiotic prophase I

Evidence from lower eukaryotes suggests that the chromosomal associations of all the structural maintenance of chromosome (SMC) complexes, cohesin, condensin and Smc5/6, are influenced by the Nipbl/Mau2 heterodimer. Whether this function is conserved in mammals is currently not known. During mammalian meiosis, very different localisation patterns have been reported for the SMC complexes, and the localisation of Nipbl/Mau2 has just recently started to be investigated. Here, we show that Nipbl/Mau2 binds on chromosomal axes from zygotene to mid-pachytene in germ cells of both sexes. In spermatocytes, Nipbl/Mau2 then relocalises to chromocenters, whereas in oocytes it remains bound to chromosomal axes throughout prophase to dictyate arrest. The localisation pattern of Nipbl/Mau2, together with those seen for cohesin, condensin and Smc5/6 subunits, is consistent with a role as a loading factor for cohesin and condensin I, but not for Smc5/6. We also demonstrate that Nipbl/Mau2 localises next to Rad51 and γH2AX foci. NIPBL gene deficiencies are associated with the Cornelia de Lange syndrome in humans, and we find that haploinsufficiency of the orthologous mouse gene results in an altered distribution of double-strand breaks marked by γH2AX during prophase I. However, this is insufficient to result in major meiotic malfunctions, and the chromosomal associations of the synaptonemal complex proteins and the three SMC complexes appear cytologically indistinguishable in wild-type and Nipbl ^+/? spermatocytes.     

Assessment of antioxidant activities in roots of Miswak (Salvadora persica) plants grown at two different locations in Saudi Arabia

Traditionally, in Middle Eastern countries, many cultures use chewing sticks of arak for medicinal purposes especially, for oral cleanliness care. It was used by Muslims for treatment of teeth and highly recommended to be used by Muslims during the whole day. Therefore, the present work aimed to determine the total phenolic content and total flavonoids in two Miswak extracts obtained from arak roots collected from two different localities in Saudi Arabia. They were extracted with aqueous ethanol (80%) and used to estimate in vitro their antioxidative abilities. The new findings showed that the two tested extracts contained significantly different amounts of both total phenolic content and total flavonoids. According to the increase of total phenolic contents and total flavonoids obtained from the two extracts, Miswak collected from the southern region was found to contain more contents than those collected from the middle region. The results of antioxidant activities of Miswak root extract obtained by using different in vitro methods were varied depending on the technique used. According to the malondialdehyde (MDA) method, hydrogen peroxide (H₂O₂) scavenging ability and 1,1-diphenyl-2-picrylhydrazyl (DPPH) methods, the two Miswak extracts exhibited to have high to very high antioxidant activities. Mostly, the values of antioxidant activities of Southern region have been shown to be always the highest.     

Technical and economic potentials of the unconventional extruded dried Arabic bread wastes in broilers diets

Food waste is one of the major global challenges that have adverse socioeconomic and environmental impacts. Therefore, studying food waste utilization potentials and minimizing its negative consequences becomes imperative. This study aims to assess the technical and economic potentials of substituting corn with unconventional extruded dried Arabic Bread waste (EDABW) in broilers’ diets, in terms of broilers’ performance, carcass characteristic, economic net returns, and income over feed cost (IOFC). One hundred eighty unsexed one-day-old broiler birds of Ross breed were distributed randomly in six treatments (0, 20, 40, 60, 80, and 100% EDABW group) of isocaloric and isonitrogenous diets in a completely randomized design with six replicated (5 chicks/replicate). The investigated traits were broilers’ performance (live body weight, total feed intake, total feed conversion ratio, and total weight gain. Other traits such as carcass weight, abdominal fat, edible offal (liver, heart, and gizzard), eviscerated (breast muscles, drum and thigh muscles, and wings) were weighed and expressed based on a live body weight. Results showed that the 20% replacement level of corn with EDABW generated the highest increase in the live body weight and the eviscerated carcass at about 4.24% g and 4.90%, respectively. On the other hand, the economic analysis showed potential reductions in the broilers’ diet cost and the total broilers' production cost as the levels of corn substitution with by unconventional EDABW increased. The reductions were estimated at 5.1%, 6.3%, 8.4%, 9.3%, and 9.9% at substitution levels of 20%, 40%, 60%, 80%, and 100%, respectively as compared to the control diet. The results also showed a potential increase in the net economic returns of broiler meat as the increase in substitution levels ranged between 3.5–06.8% and 4.3–8.3% as compared to the control diets using the average retail and wholesale prices of broiler meats, respectively. In addition, the maximum IOFC was estimated potentially at a 20% substitution level of corn with EDABW. Conclusively, the study results show promising technical and economic potentials for unconventional EDABW in broilers’ diets that could lead to a thriving industry of unconventional broilers’ diets with high net economic returns and maximum IOFC.