For example, it has been reported that smaller, hydrophilic peptides (e.g., leptin, 16 kDa) can be widely distributed throughout the CNS upon ICV delivery whereas larger polypeptides (e.g., FGF-2, 22 kDa; GDNF, 24 kDa) which also have an affinity for components (e.g., heparan sulfate) of the extracellular matrix have a more limited distribution [26], [27].
It has been reported that small pore sizes can limit cell migration and colonization [ 25, 26], vascular ingrowth, and nutrient and water transfer [ 27].
Considering antiparasitic drugs after surgery, it has been reported that small cysts, not removed by surgery, can be missed by magnetic resonance imaging and cause further complications in an already tenuous post-neurosurgical patient.
It has already been reported that small primary tumours could lead to metastasis in different cancer types (Menz et al, 1985; Sho et al, 1998; Chiang et al, 2008).
Indeed, it has been reported that small molecule inhibitors specific to FAK tyrosine kinases have both in vitro and in vivo efficacy in interfering with mammary tumour progression [ 30, 31].
The cell rounding we observed upon Rac3 siRNA treatment may be partially responsible for the decreased cell invasion and speed of wound repair in the scratch test, since it has been reported that small pseudopodia are required for cell motility and to bear focal complexes [ 30, 31].
It has been reported that small amounts of the cysteine desulfurase NFS1 and its binding partner ISD11 are expressed in the cytosolic and/or nuclear compartments of mammalian cells (Land and Rouault, 1998; Shi et al., 2009), where small amounts of the scaffold proteins ISCU and NFU1 are also present (Tong et al., 2003; Tong and Rouault, 2006).
The details of these candidate sRNAs are summarised in Additional File 4. It has been reported that small functional proteins of less than 50 amino acids [ 34, 35] and several regulatory sRNAs encode small functional peptides (so called "dual-function sRNAs") in bacteria [ 36, 37].
It has been reported that small quantities of uromodulin/THP can be detected in blood using sensitive immunoassays [ 29, 30], but it is possible that some proteins in the serum simply cross-react with the antibody raised against the uromodulin/THP proteins [ 31].
It has also been reported that small group teaching has a direct positive effect on students' motivation to learn, which has been shown to play a central role in promoting group productivity, elaboration of knowledge and interaction in different settings [ 22].
In a previous study it was reported that smaller tumor metastases in lungs was correlated significantly with bicarbonate treatment alone, but this was a 30 day experiment using β-galactosidase expressing MDA-MB-231 cells and the mean tumor diameters were about 87% of the lesion diameters measured in the untreated group [ 16].
