The potential role of mesenchymal stem cells in modulating antiageing process

Ageing and age-related diseases share some basic origin that largely converges on inflammation. Precisely, it boils down to a common pathway characterised by the appearance of a fair amount of proinflammatory cytokines known as inflammageing. Among the proposed treatment for antiageing, MSCs gained attention in recent years. Since mesenchymal stem cells (MSCs) can differentiate itself into a myriad of terminal cells, previously it was believed that these cells migrate to the site of injury and perform their therapeutic effect. However, with the more recent discovery of huge amounts of paracrine factors secreted by MSCs, it is now widely accepted that these cells do not engraft upon transplantation but rather unveil their benefits through excretion of bioactive molecules namely those involved in inflammatory and immunomodulatory activities. Conversely, the true function of these paracrine changes has not been thoroughly investigated all these years. Hence, this review will describe in detail on ways MSCs may capitalize its paracrine properties in modulating antiageing process. Through a comprehensive literature search various elements in the antiageing process, we aim to provide a novel treatment perspective of MSCs in antiageing related clinical conditions.     

Imported Malaria in Korea: a 13-Year Experience in a Single Center

The incidence of imported malaria has been increasing in Korea. We reviewed data retrospectively to evaluate the epidemiology, clinical features, and outcomes of imported malaria from 1995 to 2007 in a university hospital. All patients diagnosed with imported malaria were included. Imported malaria was defined as a positive smear for malaria that was acquired in a foreign country. A total of 49 patients (mean age, 35.7 year; M : F = 38 : 11) were enrolled. The predominant malarial species was Plasmodium falciparum (73.5%), and the most frequent area of acquisition was Africa (55.1%), followed by Southeast Asia (22.4%) and South Asia (18.4%). Fourteen-patients (30.6%) suffered from severe malaria caused by P. falciparum and 1 patient (2.0%) died of multiorgan failure. Most of the patients were treated with mefloquine (79.2%) or quinine (10.2%); other antimalarial agents had to be given in 13.2% treated with mefloquine and 44.4% with quinine due to adverse drug events (ADEs). P. falciparum was the most common cause of imported malaria, with the majority of cases acquired from Africa, and a significant number of patients had severe malaria. Alternative antimalarial agents with lower rates of ADEs might be considered for effective treatment instead of mefloquine and quinine.     

Expression of theRSI-1 gene during development of roots and reproductive organs in tomato

TheRSI-1 gene is expressed in pericycle cells just prior to the first round of cell division for lateral root development in tomato. We transformed tomato plants with theRSI-1 gene promoter linked to a GUS reporter gene. GUS activity was detected not only at the sites of initiation for lateral and adventitious roots, but also at the primary root tip. Expression of the fusion gene was also regulated at various stages of tissue development: in particular, during the formation of reproductive organs such as pollen and fruit Overexpression of theRSI-1 gene in either the sense or antisense orientation resulted in arrest of fruit development and seed germination. TheRSI-1 gene product, therefore, may play a role in auxin-induced cell division in various developing tissues. Inter and intramolecular disulfide bridges between cysteines rich in the RSI-1 protein might be involved in cell-wall modifications that are essential for new cell division. These hypotheses for the role of theRSI-1 gene in lateral-root and reproductive-organ development remain to be tested.     

Lack of association between FOS polymorphisms and clearance of HBV infection as well as HCC occurrence

Human v-Fos Finuel-Biskis-Jinkins (FBJ) murine osteosarcoma viral oncogene homolog (FOS) is located in 14q24.3. The FOS protein is a constituent of the activating protein-1 (AP-1) and its increased expression in the hepatocellular carcinoma (HCC) have been reported. In this study, the association of FOS polymorphisms with the HBV infection and HCC occurrence were evaluated in Korean patients. After re-sequencing in 24 unrelated healthy individuals, two common single nucleotide polymorphisms (SNPs) in regulatory regions that were selected based on linkage disequilibrium were genotyped in a total of 1,093 Korean subjects including 656 HBV chronic carriers, who were further stratified into chronic hepatitis/liver cirrhosis (CH/LC, n = 339) and HCC (n = 317) groups, and 437 spontaneously recovered (SR) controls. Logistic regression and Cox relative hazard analysis showed no significant association of regulatory polymorphisms and haplotypes in FOS with HBV clearance and HCC development (P > 0.05, respectively).     

Dynactin integrity depends upon direct binding of dynamitin to Arp1

Dynactin is a multiprotein complex that works with cytoplasmic dynein and other motors to support a wide range of cell functions. It serves as an adaptor that binds both dynein and cargoes and enhances single-motor processivity. The dynactin subunit dynamitin (also known as p50) is believed to be integral to dynactin structure because free dynamitin displaces the dynein-binding p150^Glued subunit from the cargo-binding Arp1 filament. We show here that the intrinsically disordered dynamitin N-terminus binds to Arp1 directly. When expressed in cells, dynamitin amino acids (AA) 1–87 causes complete release of endogenous dynamitin, p150, and p24 from dynactin, leaving behind Arp1 filaments carrying the remaining dynactin subunits (CapZ, p62, Arp11, p27, and p25). Tandem-affinity purification–tagged dynamitin AA 1–87 binds the Arp filament specifically, and binding studies with purified native Arp1 reveal that this fragment binds Arp1 directly. Neither CapZ nor the p27/p25 dimer contributes to interactions between dynamitin and the Arp filament. This work demonstrates for the first time that Arp1 can directly bind any protein besides another Arp and provides important new insight into the underpinnings of dynactin structure.     

Paradoxical Survival: Examining the Parrondo Effect across Biology

Parrondo's paradox, in which losing strategies can be combined to produce winning outcomes, has received much attention in mathematics and the physical sciences; a plethora of exciting applications has also been found in biology at an astounding pace. In this review paper, the authors examine a large range of recent developments of Parrondo's paradox in biology, across ecology and evolution, genetics, social and behavioral systems, cellular processes, and disease. Intriguing connections between numerous works are identified and analyzed, culminating in an emergent pattern of nested recurrent mechanics that appear to span the entire biological gamut, from the smallest of spatial and temporal scales to the largest—from the subcellular to the complete biosphere. In analyzing the macro perspective, the pivotal role that the paradox plays in the shaping of biological life becomes apparent, and its identity as a potential universal principle underlying biological diversity and persistence is uncovered. Directions for future research are also discussed in light of this new perspective.