Article #1:
The article focussed on the breeding behaviours of emperor penguins that are recently discovered with the help of satellites. Mostly it is believed that penguins lay their eggs on sea ice that is fast and stable and that remains intact under the chick fledge. Fretwell and co-workers conducted this study on forty-six colonies emperor penguins. The recent observation revealed that few colonies of emperor penguins breed on ice-shelves instead of sea ice. Due to rapid climate changes and the incidence of ice melting the penguin population has declined and very close to extinction. It is a big concern that how a species will survive that is totally dependent on sea ice.
The study by Fretwell and co-workers tried to investigate that this newly discovered behaviour of Emperor penguins is whether as adaptive process due to climate change or it has not been noticed yet. The researchers evaluated the flexibility of phenotypes in regards to understand the adaptation process among animals. .
The different fostering sites of penguin were investigated through aerial surveys using satellites. These included sites were ice shelves of Barrier Bay colony, Shackleton Ice Shelf colony, Jason Peninsula, Larsen C Ice Shelf, and Ruppert Coast colony.
The colonies were screened regularly for several years on the same positions. To know the reason for breeding site shift from sea-ice to Sea-shelf ENVISAT synthetic aperture radar imagery was utilised. The most interesting fact discovered in this study was that it was the normal breeding behaviour exclusively among emperor penguins which could not be noticed by earlier experts. The article also described the explanation responsible for this negligence indicating it as a recent phenotypic plasticity or a lack of systematic searches for emperor penguins behaviour on ice shelves (Fretwell et al.).
Article #2:
Streptococcus mutans is the most common bacterial agent causing dental caries. It demineralizes the tooth minerals through metabolising the dietary carbohydrate which releases acid that in turn reduces the pH creating an acidic environment. This bacterium is highly capable of releasing and tolerating the acidic milieu thus, can colonise effectively in the oral cavity leading to the formation of that highly cariogenic dental biofilms. Several chemotherapeutic agents have shown promising effects for prevention of various dental or oral diseases. Zingiber officinale (ginger) is the most used Indian herbs that are popular in combating the oral problems. In a study conducted by Hasan, Danishuddin and Khan they comparatively assess the impacts of rudimentary extracts and the methanolic fraction of Z. officinale against S. mutans virulence factor.
They investigated the in vitro as well as in vivo action of crude extracts and its methanolic fraction against cariogenic possessions of S. mutans. The study revealed that the ginger extract was capable of inhibiting the various virulence properties of bacterium that were crucial for its pathogenesis. The ginger extracts showed effective results on plaque biofilm and succeeded in reducing its extent. It also inhibited the glucan synthesis and bacterial adherence to the teeth.
The article presented a very valuable finding that can be implemented in treating various dental problems and showed the potential of crude extract of Z. officinale as well as its methanolic fraction against the complete range of cariogenic property of S. Mutans (Hasan, Danishuddin and Khan).
Article #3:
The third article was authored by Indrayani Waghmare, who investigated the altered signalling interactions in Drosophila epithelial tumour model. The study evaluated the process of signalling interactions in Drosophila and presented an array of proteins and genes material involved in the process. Moreover, how they interact with each other in the process as well as influence each other activity. The complex interactions in tumour play a significant role in tumorigenesis and cancer development. It is essential to analyse the interactions between oncogenic genetic abrasions to explain the tumour progression. Drosophila melanogaster is the best animal model that facilitates the study of the behaviour of cells in tumour progression. The interactions of oncogenic protein Ras (V12) and loss-of-function mutations, occurred in the tumour suppressor scribbled (scrib) results in metastatic tumours which are also seen in human cancers. The article stated that that Rasv12+scrib-/- cells act as winning cells in super competition. Moreover, the cell competitive, (JNK and Yki) signals and compensatory signals (Wg, Dronc, JNK and Yki) are seized during the super competition.
During this process, the pro-apoptotic proteins including Dronc and JNK play a non-apoptotic role. Wg acts as upstream of JNK-Yki positive feedback loop that results in the signal intensification of JNK and Yki activities that are essential for antagonistic growth. This study by Waghmare provided a substantial genetic data valuable for understanding the oncogenic collaboration between RasV12 and scrib, which constitute the signalling core skeleton of tumorigenesis (Waghmare).
Works cited
Fretwell, Peter T., et al. "Emperor penguins breeding on iceshelves." PloS one 9.1 (2014):
e85285.
Hasan, Sadaf, Mohd Danishuddin, and Asad U. Khan. "Inhibitory effect of zingiber officinale
towards Streptococcus mutans virulence and caries development: in vitro and in vivo
studies." BMC microbiology 15.1 (2015): 1.
Waghmare, Indrayani. Altered signaling interactions in Drosophila epithelial
tumor model
