Sexual signalling in female crested macaques and the evolution of primate fertility signals

Background

Host-parasite coevolution can lead to local adaptation of either parasite or host if there is specificity (GxG interactions) and asymmetric evolutionary potential between host and parasite. This has been demonstrated both experimentally and in field studies, but a substantial proportion of studies fail to detect such clear-cut patterns. One explanation for this is that adaptation can be masked by counter-adaptation by the antagonist. Additionally, genetic architecture underlying the interaction is often highly complex thus preventing specific adaptive responses. Here, we have employed a reciprocal cross-infection experiment to unravel the adaptive responses of two components of fitness affecting both parties with different complexities of the underlying genetic architecture (i.e. mortality and spore load). Furthermore, our experimental coevolution of hosts (Tribolium castaneum) and parasites (Nosema whitei) included paired replicates of naive hosts from identical genetic backgrounds to allow separation between host- and parasite-specific responses.

Results

In hosts, coevolution led to higher resistance and altered resistance profiles compared to paired control lines. Host genotype × parasite genotype interactions (G_H × G_P) were observed for spore load (the trait of lower genetic complexity), but not for mortality. Overall parasite performance correlated with resistance of its matching host coevolution background reflecting a directional and unspecific response to strength of selection during coevolution. Despite high selective pressures exerted by the obligatory killing parasite, and host- and parasite-specific mortality profiles, no general pattern of local adaptation was observed, but one case of parasite maladaptation was consistently observed on both coevolved and control host populations. In addition, the use of replicate control host populations in the assay revealed one case of host maladaptation and one case of parasite adaptation that was masked by host counter-adaptation, suggesting the presence of complex and probably dynamically changing fitness landscapes.

Conclusions

Our results demonstrate that the use of replicate naive populations can be a useful tool to differentiate between host and parasite adaptation in complex and dynamic fitness landscapes. The absence of clear local adaptation patterns during coevolution with a sexual host showing a complex genetic architecture for resistance suggests that directional selection for generality may be more important attributes of host-parasite coevolution than commonly assumed.     

Heterologous expression,characterization and evaluation of the matrix protein from Newcastle disease virus as a target for antiviral therapies

Newcastle disease virus (NDV) is an infectious agent of a large variety of birds, including chicken, which poses a real threat to the agriculture industry. Matrix (M) proteins of NDV and many other viruses perform critical functions during viral assembly and budding from the host cell. M-proteins are well conserved and therefore are potential targets for antiviral therapies. To validate this, we expressed the NDV M-protein in its native form in Saccharomyces cerevisiae and in inclusion bodies in Escherichia coli. Proper refolding of the recombinant protein produced in E. coli was verified using circular dichroism and infrared spectroscopies and electron microscopy. Immunization of chickens with the NDV M-protein elicited significant serum antibody titers. However, the antibodies conferred little protection against the ND following lethal viral challenges. We conclude that the M-protein is not exposed on the surface of the host cell or the virus at any stage during its life cycle. We discuss how the conserved M-protein can further be exploited as an antiviral drug target.     

Use of aged refuse-based bioreactor/biofilter for landfill leachate treatment

Sanitary landfilling is a proven way for disposal of municipal solid waste (MSW) in developed countries in general and in developing countries in particular, owing to its low immediate costs. On the other hand, landfilling is a matter of concern due to its generation of heavily polluted leachate. Landfill leachate becomes more refractory with time and is very difficult to treat using conventional biological processes. The aged refuse-based bioreactor/biofilter (ARB) has been shown to be a promising technology for the removal of various pollutants from landfill leachate and validates the principle of waste control by waste. Based on different environmental and operational factors, many researchers have reported remarkable pollutant removal efficiencies using ARB. This paper gives an overview of various types of ARBs used; their efficiencies; and certain factors like temperatures, loading rates, and aerobic/anaerobic conditions which affect the performance of ARBs in eliminating pollutants from leachate. Treating leachate by ARBs has been proved to be more cost-efficient, environment friendly, and simple to operate than other traditional biological techniques. Finally, future research and developments are also discussed.     

Expanding the Repertoire of Gene Tools for Precise Manipulation of the Clostridium difficile Genome: Allelic Exchange Using pyrE Alleles

Sophisticated genetic tools to modify essential biological processes at the molecular level are pivotal in elucidating the molecular pathogenesis of Clostridium difficile, a major cause of healthcare associated disease. Here we have developed an efficient procedure for making precise alterations to the C. difficile genome by pyrE-based allelic exchange. The robustness and reliability of the method was demonstrated through the creation of in-frame deletions in three genes (spo0A, cwp84, and mtlD) in the non-epidemic strain 630Δerm and two genes (spo0A and cwp84) in the epidemic PCR Ribotype 027 strain, {"type":"entrez-nucleotide","attrs":{"text":"R20291","term_id":"774925","term_text":"R20291"}}R20291. The system is reliant on the initial creation of a pyrE deletion mutant, using Allele Coupled Exchange (ACE), that is auxotrophic for uracil and resistant to fluoroorotic acid (FOA). This enables the subsequent modification of target genes by allelic exchange using a heterologous pyrE allele from Clostridium sporogenes as a counter-/negative-selection marker in the presence of FOA. Following modification of the target gene, the strain created is rapidly returned to uracil prototrophy using ACE, allowing mutant phenotypes to be characterised in a PyrE proficient background. Crucially, wild-type copies of the inactivated gene may be introduced into the genome using ACE concomitant with correction of the pyrE allele. This allows complementation studies to be undertaken at an appropriate gene dosage, as opposed to the use of multicopy autonomous plasmids. The rapidity of the ‘correction’ method (5–7 days) makes pyrE ⁻ strains attractive hosts for mutagenesis studies.     

Relationships between gas-exchange characteristics and stomatal structural modifications in some desert grasses under high salinity

Two populations, one from lesser saline Derawar Fort (DF) and the other from highly saline Ladam Sir (LS) in the Cholistan desert, for each of the five grass species, Aeluropus lagopoides, Cymbopogon jwarancusa, Lasiurus scindicus, Ochthochloa compressa, and Sporobolus ioclados were examined to investigate the influence of salinity on structural and functional characteristics of stomata. Salinity tolerance in A. lagopoides mainly depended on controlled transpiration rate (E) and high water-use efficiency (WUE), which was found to be regulated by fewer and smaller stomata on both leaf surfaces as well as stomatal encryption by epidermal invaginations. C. jwarancusa had sunken stomata on the abaxial surface only, which largely reflected a reduced E, but less affected stomatal conductance (g _s) or WUE. L. scindicus had fewer but larger stomata along with hairs/trichomes which may function to avoid water loss through transpiration, and hence, to attain a high WUE. In O. compressa stomata were found only on the abaxial surface and these were completely encrypted by epidermal invaginations as well as a dense covering of microhairs, which was associated with a low E and high WUE under salinity stress. In S. ioclados, the traits of increased stomatal density and decreased stomatal area may be critical for stomatal regulation under salt-prone environments. High stomatal regulation depended largely on stomatal density, area, and degree of encryption under salinity, which is of great ecophysiological significance for plants growing under osmotic stresses.     

A novel synthesis and antimicrobial activity of 1-[(Substituted-phenyl) sulfonyl]pyrrolidin-2-ones

Novel cyclization of 4-(substituted-phenylsulfonamido)butanoic acids to their corresponding 1-[(substituted-phenyl)sulfonyl]pyrrolidin-2-ones was successfully achieved by using polyphosphate ester (PPE). The reaction time was considerably reduced with corresponding increase in the yields, when polyphosphate ester (PPE) was used in combination with 4-(N,N-dimethylamino)pyridine (DMAP). All the synthesized compounds were screened for their antimicrobial activity. Minimum Inhibitory Concentration (MIC) values of synthesized compounds were also determined, and were found to be in the range of 0.09-1.0 mg.     

Study of rust resistance genes in wheat germplasm with DNA markers

Wheat is a vital dietary component for human health and widely consumed in the world. Wheat rusts are dangerous pathogens and contribute serious threat to its production. In present study, PCR-Based DNA Markers were employed to check the rust resistance genes among 20 wheat genotypes and 22 markers were amplified. NTSYS-pc 2.2 was used to calculate genetic diversity and Nei and Li''s coefficients ranged from 0.55 to 0.95. Cluster analysis was obtained using UPGMA (Unweighted Pair Group Method of Arithmetic Average) algorithm. Maximum no. of genes (23) was amplified from TW-760010 genotype whereas minimum no of genes (14) were amplified from TW-76005 genotype. The data gained from present study open up new ways to produce new varieties by breeding rust resistant germplasm to avoid the economic and food loss and varieties with improved characteristics.     

P2RY1/ALK3-Expressing Cells within the Adult Human Exocrine Pancreas Are BMP-7 Expandable and Exhibit Progenitor-like Characteristics

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Anaplastic thyroid cancer: outcomes of trimodal therapy

BackroundThe purpose of this study is to assess the impact of trimodal therapy [surgery, chemotherapy and external beam radiotherapy (EBRT)] in patients with anaplastic thyroid cancer (ATC) treated with curative intent.Materials and methodsRetrospective review of patients with ATC treated at a tertiary referral centre between January 2009 and June 2020. Data were collected regarding demographics, histology, staging, treatment and outcomes.ResultsSeven patients (4 female) were identified. Median age was 58 years (range 52–83 years). All patients received EBRT with concurrent doxorubicin. Six patients received surgery followed by chemoradiotherapy (CRT), and one underwent neoadjuvant CRT followed by surgery. Median radiological tumour size was 50mm (range 40–90 mm). Six patients had gross extrathyroidal extension and three had N1b disease. Prescribed radiotherapy schedules were 46.4 Gy in 29 bidaily fractions (n = 2, treated 2010), 60 Gy in 30 daily fractions (n = 2), 66 Gy in 30 fractions (n = 2) and 70 Gy in 35 fractions (n = 1; patient received neoadjuvant CRT). CRT was discontinued early for two patients due to toxicities. At median follow up of 5.8 months, 42.9% (3/7) patients were alive and disease-free. Only one patient developed a local failure. Three patients died from distant metastases without locoregional recurrence.ConclusionsDespite poor prognosis of ATC, selected patients with operable tumours may achieve high locoregional control rates with trimodal therapy, with possibility of long-term survival in select cases.