Informational masking emerges with processing of complex sounds in the central auditory system and can be affected by uncertainty emerging from trial-to-trial variation of stimulus features. Uncertainty can be non-informative but confusing and thus mask otherwise salient stimulus changes resulting in increased discrimination thresholds. With increasing age, the ability for processing of such complex sound scenes degrades. Here, 6 young and 4 old gerbils were tested behaviorally in a vowel discrimination task. Animals were trained to discriminate between sequentially presented target and reference vowels of the vowel pair/I/-/i/. Reference and target vowels were generated shifting the three formants of the reference vowel in steps towards the formants of the target vowels. Non-informative but distracting uncertainty was introduced by random changes in location, level, fundamental frequency or all three features combined. Young gerbils tested with uncertainty for the target or target and reference vowels showed similar informational masking effects for both conditions. Young and old gerbils were tested with uncertainty for the target vowels only. Old gerbils showed no threshold increase discriminating vowels without uncertainty in comparison with young gerbils. Introducing uncertainty, vowel discrimination thresholds increased for young and old gerbils and vowel discrimination thresholds increased most when presenting all three uncertainty features combined. Old gerbils were more susceptible to non-informative uncertainty and their thresholds increased more than thresholds of young gerbils. Gerbils' vowel discrimination thresholds are compared to human performance in the same task (Eipert et al., 2019). L86-8275 Aberrant expression of c-MYC oncogene is significantly associated with the occurrence and development of malignant melanoma. Suppression of the c-MYC transcriptional activity accordingly provides a new idea for treating melanoma. Notably, stabilizing the G-quadruplex (G4) structure in the promoter is proved to be effective in downregulating c-MYC transcription. In this work, we developed a drug-like imidazole-benzothiazole conjugate called IZTZ-1, which was confirmed to preferentially stabilize the promoter G4 and thus lower c-MYC expression. Intracellular assays revealed that IZTZ-1 induced cell cycle arrest, apoptosis, thereby inhibiting cell proliferation. Furthermore, IZTZ-1 was demonstrated to effectively inhibit tumor growth in a melanoma mouse model. Consequently, IZTZ-1 showed good potential in the treatment of melanoma. This study provides an alternative strategy to treat melanoma by targeting the c-MYC G4. With respect to the main role of amyloid-β (Aβ) plaques as one of the pathological hallmarks in the brain of Alzheimer's patients, the development of new imaging probes for targeted detection of Aβ plaques has attracted considerable interests. In this study, a novel cyclopentadienyl tricarbonyl Technetium-99 m (99mTc) agent with peptide scaffold, 99mTc-Cp-GABA-D-(FPLIAIMA)-NH2, for binding to the Aβ plaques was designed and successfully synthesized using the Fmoc solid-phase peptide synthesis method. This radiopeptide revealed a good affinity for Aβ42 aggregations (Kd = 20 µM) in binding affinity study and this result was confirmed by binding to Aβ plaques in brain sections of human Alzheimer's disease (AD) and rat models using in vitro autoradiography, fluorescent staining, and planar scintigraphy. Biodistribution studies of radiopeptide in AD and normal rats demonstrated a moderate initial brain uptake about 0.38 and 0.35% (ID/g) 2 min post-injection, respectively. Whereas, AD rats showed a notable retention time in the brain (0.23% ID/g at 30 min) in comparison with fast clearance in normal rat brains. Normal rats following treatment with cyclosporine A as a p-glycoprotein inhibitor showed a significant increase in the radiopeptide brain accumulation compared to non-treated ones. There was a good correlation between data gathered from single-photon emission computed tomography/computed tomography (SPECT/CT) imaging and biodistribution studies. Therefore, these findings showed that this novel radiopeptide could be a potential SPECT imaging agent for early detection of Aβ plaques in the brain of patients with AD. Molecular imaging techniques are increasingly being used in localization, staging and therapy control of cancer. Due to their unique target specificity for the endogenous receptors, radiopeptides have been used widely for the development of radiopharmaceuticals for targeted tumor imaging in nuclear oncology. It is necessary to modify radiolabeled peptides in order to achieve more effective agents. Structural modifications of amino acid chains have significant effect on the metabolic stability, biological activity and efficiency of peptide conjugates that are currently applied as imaging tracers. There are several ways to modify the peptide chain but the most common strategies include amino acid substitutions, cyclization and multimerization. In this review, we have focused on studies involving these kind of modifications on amino acid sequences of radiolabeled peptides and we have provided an overview of the effects of these chemical modifications on the in vitro and in vivo properties of these radioconjugates and their potential as SPECT (Single photon emission computed tomography) and PET (positron emission tomography) imaging agents. Calcium phosphate is the inorganic mineral of hard tissues such as bone and teeth. Due to their similarities to the natural bone, calcium phosphates are highly biocompatible and biodegradable materials that have found numerous applications in dental and orthopedic implants and bone tissue engineering. In the form of nanoparticles, calcium phosphate nanoparticles (CaP's) can also be used as effective delivery vehicles to transfer therapeutic agents such as nucleic acids, drugs, proteins and enzymes into tumor cells. In addition, facile preparation and functionalization of CaP's, together with their inherent properties such as pH-dependent solubility provide advantages in delivery and release of these bioactive agents using CaP's as nanocarriers. In this review, the challenges and achievements in the intracellular delivery of these agents to tumor cells are discussed. Also, the most important issues in the design and potential applications of CaP-based biominerals are addressed with more focus on their biodegradability in tumor microenvironment.