Human granulocyte colony stimulating factor (hG-CSF): cloning,overexpression, purification and characterization

Background  

Biopharmaceutical drugs are mainly recombinant proteins produced by biotechnological tools. The patents of many biopharmaceuticals have expired, and biosimilars are thus currently being developed. Human granulocyte colony stimulating factor (hG-CSF) is a hematopoietic cytokine that acts on cells of the neutrophil lineage causing proliferation and differentiation of committed precursor cells and activation of mature neutrophils. Recombinant hG-CSF has been produced in genetically engineered Escherichia coli (Filgrastim) and successfully used to treat cancer patients suffering from chemotherapy-induced neutropenia. Filgrastim is a 175 amino acid protein, containing an extra N-terminal methionine, which is needed for expression in E. coli. Here we describe a simple and low-cost process that is amenable to scaling-up for the production and purification of homogeneous and active recombinant hG-CSF expressed in E. coli cells.     

Macrozoobenthic communities of underwater landscapes in the shallow-water zone of southern Lake Baikal

Species composition and distribution of macrozoobenthos have been studied in the shallow water zone (0–20 m) of Southern Lake Baikal (Bolshiye Koty Bay). The amount of taxa recorded reached up to 244 species distributed among 16 distinctive communities of complex structure and high species diversity. The Shannon index of specific diversity was found to vary between 2.9 and 4.8 bits. Mosaic spatial distribution of communities is controlled by both biotic and abiotic factors. Trophic zones with respect to the bottom-dwellers are determined by two lithodynamic phenomena: washout and accumulation of thin deposits (fine to medium silt and mud). The bottom with coarse clastic material (pebbles and boulders), where fine sediments are eroded and resuspended, is dominated by immobile and mobile sestonophagous species as well as by the communities dominated by detrito- and phytophagous species. Areas with soft fine sediments are dominated by macro-invertebrates, which ingest the substrate indiscriminately.     

The Genome Sequence of a Type ST239 Methicillin-Resistant Staphylococcus aureus Isolate from a Malaysian Hospital

We report the genome sequence of a healthcare-associated MRSA type ST239 clone isolated from a patient with septicemia in Malaysia. This clone typifies the characteristics of ST239 lineage, including resistance to multiple antibiotics and antiseptics.     

Ultrastructural changes in synaptic junctions of the mouse neocortex during rehabilitation after prolonged protein-calorie malnutrition

The quantitative ultrastructural study of neocortical synaptic junctions has been performed during rehabilitation after protein-caloric deficiency. It has been shown that simple food rehabilitation does not lead to absolute restoration of synaptic junctions. However, food rehabilitation with carnitine restores the ultrastructure of synaptic junctions, with the length of the active zones and the number of spine apparatus cisterns exceeding the control values. Nevertheless, synaptic cleft width and postsynaptic density remain lower than in the control group, both after simple food rehabilitation and food rehabilitation with carnitine.     

Distinct α2 Na,K-ATPase membrane pools are differently involved in early skeletal muscle remodeling during disuse

The Na,K-ATPase is essential for the contractile function of skeletal muscle, which expresses the α1 and α2 subunit isoforms of Na,K-ATPase. The α2 isozyme is predominant in adult skeletal muscles and makes a greater contribution in working compared with noncontracting muscles. Hindlimb suspension (HS) is a widely used model of muscle disuse that leads to progressive atrophy of postural skeletal muscles. This study examines the consequences of acute (6–12 h) HS on the functioning of the Na,K-ATPase α1 and α2 isozymes in rat soleus (disused) and diaphragm (contracting) muscles. Acute disuse dynamically and isoform-specifically regulates the electrogenic activity, protein, and mRNA content of Na,K-ATPase α2 isozyme in rat soleus muscle. Earlier disuse-induced remodeling events also include phospholemman phosphorylation as well as its increased abundance and association with α2 Na,K-ATPase. The loss of α2 Na,K-ATPase activity results in reduced electrogenic pump transport and depolarized resting membrane potential. The decreased α2 Na,K-ATPase activity is caused by a decrease in enzyme activity rather than by altered protein and mRNA content, localization in the sarcolemma, or functional interaction with the nicotinic acetylcholine receptors. The loss of extrajunctional α2 Na,K-ATPase activity depends strongly on muscle use, and even the increased protein and mRNA content as well as enhanced α2 Na,K-ATPase abundance at this membrane region after 12 h of HS cannot counteract this sustained inhibition. In contrast, additional factors may regulate the subset of junctional α2 Na,K-ATPase pool that is able to recover during HS. Notably, acute, low-intensity muscle workload restores functioning of both α2 Na,K-ATPase pools. These results demonstrate that the α2 Na,K-ATPase in rat skeletal muscle is dynamically and acutely regulated by muscle use and provide the first evidence that the junctional and extrajunctional pools of the α2 Na,K-ATPase are regulated differently.     

Heterogeneity in the accessory olfactory system

The mammalian accessory olfactory bulb (AOB) is chemoarchitecturally heterogeneous in that it stains differentially with a number of markers; the receptor cells that project to the AOB are similarly heterogeneous. What is the significance of this heterogeneity? We have found that the AOB of the gray, short-tailed opossum, Monodelphis domestica, stains differentially with a number of 'markers': antibodies to olfactory marker protein (OMP) and the alpha subunit of the G protein Gi2, the lectin of Vicia villosa and NADPH-diaphorase. These markers stain the rostral AOB more strongly than the caudal AOB whereas, the G protein subunit G(o) alpha is located predominantly in the posterior subdivision of the AOB. This heterogeneity in the chemoarchitecture of the AOB may reflect a fundamental organizational dichotomy within the vomeronasal system that corresponds to a functional dichotomy. The vomeronasal sensory epithelium also exhibits a chemoarchitectural heterogeneity: receptor cells in the basal third are G(o) alpha-immunoreactive whereas the cells in the middle third are Gi2 alpha-immunoreactive. Tracing studies using WGA-HRP demonstrate that the neurons in the middle third of the vomeronasal sensory epithelium project their axons to the anterior AOB whereas those in the basal third appear to project to the posterior AOB.      

Effect of protein-calorie deficiency on the ultrastructure of synapses in the molecular layer of the cerebellar cortex in developing and adult animals

The influence of protein-caloric deficiency on the ultrastructure of synapses in the molecular layer of the cerebellum has been quantitatively assessed in young and adult mice. It has been found that protein-caloric deficiency in the early postnatal period delays the time of axo-dendritic synapse development in the neuropil. Adult mice were more resistant to the influence of protein-caloric deficiency because of an increase in compensatory-adaptive reactions found in the cerebellum.     

Phylogenetic relationships of the Baikal endemic Paratanytarsus baicalensis (Tshern.) with representatives of genera Paratanytarsus Thien. et Bause and Micropsectra Kieff. (Diptera, Chironomidae)

The phylogenetic relationships of the Baikal endemic chironomid Paratanytarsus baicalensis (Tshern.) and other representatives of the tribe Tanytarsini were studied using 117 partial sequences of the mitochondrial COI gene from 33 species of the genera Paratanytarsus and Micropsectra. The results show that the Baikal species is close in origin to two geographically distant European species, P. austriacus and P. hyperboreus, and itself splits into two genetically distinct clades.