Roaz, a rat C2H2 zinc finger protein, plays a role in the regulation of olfactory neuronal differentiation through its interaction with the Olf-1/EBF transcription factor family. An additional role for the Roaz/Olf-1/EBF heterodimeric protein is suggested by its ability to regulate gene activation at a distinct promoter lacking Olf-1/EBF-binding sites. Using an in vitro binding-site selection assay (Selex), we demonstrate that Roaz protein binds to novel inverted perfect or imperfect repeats of GCACCC separated by 2 bp. We show that Roaz is capable of binding to a canonical consensus recognition sequence with high affinity (Kd = 3 nM). Analysis of the structural requirement for protein dimerization and DNA binding by Roaz reveals the role of specific zinc finger motifs in the Roaz protein for homodimerization and heterodimerization with the Olf-1/EBF transcription factor. The DNA-binding domain of Roaz is mapped to the N-terminal 277 amino acids, containing the first seven zinc finger motifs, which confers weak monomeric binding to a single half site and a stronger dimeric binding to the inverted repeat in a binding-site-dependent manner. Full-length protein can form dimers on both the inverted repeat and direct repeat but not on a single half site. These findings support the role of the TFIIIA-type Zn fingers in both protein-protein interaction and protein-DNA interaction and suggest distinct functions for specific motifs in proteins with a large number of zinc finger structures.
Psychogenic anejaculation on the day of oocyte retrieval is uncommon in in vitro fertilization (IVF) programs. Before the use of intracytoplasmic sperm injection (ICSI), either the cycle had to be canceled or a sperm donor recruited.Two couples were enrolled for IVF. On the day of oocyte retrieval, the male partners developed psychogenic anejaculation.In cases of psychogenic anejaculation during IVF, percutaneous epididymal sperm aspiration can be utilized to obtain sperm for ICSI.
Mycophenolic acid (MPA) is commonly used for organ rejection prophylaxis via oral administration in the clinic. Recent studies have shown that MPA also has anticancer activities. To explore new therapeutic options for oral precancerous/cancerous lesions, MPA was designed to release topically on the dorsal tongue surface via a mucoadhesive patch. The objective of this study was to establish the pharmacokinetic (PK) and tongue tissue distribution of mucoadhesive MPA patch formulation after supralingual administration in rats and also compare the PK differences between oral, intravenous, and supralingual administration of MPA. Blood samples were collected from Sprague Dawley rats before and after a single intravenous bolus injection, a single oral dose, or a mucoadhesive patch administration on the dorsal tongue surface for 4 h, all with a dose of 0.5 mg/kg of MPA. Plots of MPA plasma concentration versus time were obtained. As multiple peaks were found in all three curves, the enterohepatic recycling (EHR) model in the Phoenix software was adapted to describe their PK parameters with an individual PK analysis method. The mean half-lives of intravenous and oral administrations were 10.5 h and 7.4 h, respectively. The estimated bioavailability after oral and supralingual administration was 72.4% and 7.6%, respectively. There was a 0.5 h lag-time presented after supralingual administration. The results suggest that the systemic plasma MPA concentrations were much lower in rats receiving supralingual administration compared to those receiving doses from the other two routes, and the amount of MPA accumulated in the tongue after patch application showed a sustained drug release pattern. Studies on the dynamic of drug retention in the tongue after supralingual administration showed that ~3.8% of the dose was accumulated inside of tongue right after the patch removal, ~0.11% of the dose remained after 20 h, and ~20.6% of MPA was not released from the patches 4 h after application. The data demonstrate that supralingual application of an MPA patch can deliver a high amount of drug at the site of administration with little systemic circulation exposure, hence lowering the potential gastrointestinal side effects associated with oral administration. Thus, supralingual administration is a potential alternative route for treating oral lesions.
The liver is a major organ that performs essential metabolic functions. Developing an efficient and safe method to knock down gene expression in the liver provides an important tool for determining gene function in liver pathophysiology. In this study, we describe a method for intrasplenic injection of adeno-associated virus serotype 8 (AAV8) engineered to express a small hairpin RNA (shRNA) against a target gene of interest, nucleostemin (NS). Intrasplenic injection of AAV8 expressing an NS-targeting shRNA (AAV8-shNS1) achieved the same knockdown efficiency of NS in the liver as did portal vein injection, compared to the injection of AAV8 expressing a scrambled sequence shRNA (AAV8-shScr). Furthermore, injection of the AAV8-shRNA virus triggered minimal inflammatory reactions in the liver parenchyma. Most importantly, this intrasplenic injection protocol was not technically demanding and caused minimal bleeding at the injection site, which is the leading cause of perioperative and postoperative mortality when performing portal vein injection. This study reports an improved and relatively safe method to achieve efficient gene knockdown in the liver.
Additional file 3: Table 1. Aging differentially methylated regions (DMRs) identified by comparing between 16-m/o (A16), 8-m/o (A8), and/or 2-m/o (A2) livers (n = 4 for each group). DNA methylation data for individual aging samples are available in GEO (GSE211999).