A fluorescence polarization assay for high-throughput screening of inhibitors against HIV-1 Nef-mediated CD4 downregulation.

Therapeutic inhibition of the viral protein Nef is an intriguing direction of antiretroviral drug discovery-it may revitalize immune mechanisms to target, and potentially clear, HIV-1-infected cells. Of the many cellular functions of Nef, the most conserved is the downregulation of surface CD4, which takes place through Nef hijacking the clathrin adaptor protein complex 2 (AP2)-dependent endocytosis. Our recent crystal structure has unraveled the molecular details of the CD4-Nef-AP2 interaction. Guided by the new structural knowledge, we have developed a fluorescence polarization-based assay for inhibitor screening against Nef's activity on CD4. In our assay, AP2 is included along with Nef to facilitate the proper formation of the CD4-binding pocket and a fluorescently labeled CD4 cytoplasmic tail binds competently to the Nef-AP2 complex generating the desired polarization signal. The optimized assay has a good signal-to-noise ratio, excellent tolerance of dimethylsulfoxide and detergent, and the ability to detect competitive binding at the targeted Nef pocket, making it suitable for high-throughput screening.

A fluorescence polarization assay for high-throughput screening of inhibitors against HIV-1 Nef-mediated MHC-I downregulation.

The multifunctional, HIV-1 accessory protein Nef enables infected cells to evade host immunity and thus plays a key role in viral pathogenesis. One prominent function of Nef is the downregulation of major histocompatibility complex class I (MHC-I), which disrupts antigen presentation and thereby allows the infected cells to evade immune surveillance by the cytotoxic T cells. Therapeutic inhibition of this Nef function is a promising direction of antiretroviral drug discovery as it may revitalize cytotoxic T cells to identify, and potentially clear, hidden HIV-1 infections. Guided by the crystal structure of the protein complex formed between Nef, MHC-I, and the hijacked clathrin adaptor protein complex 1, we have developed a fluorescence polarization-based assay for inhibitor screening against Nef's activity on MHC-I. The optimized assay has a good signal-to-noise ratio, substantial tolerance of dimethylsulfoxide, and excellent ability to detect competitive inhibition, indicating that it is suitable for high-throughput screening.

Effect of Short-term Deep Breathing Exercises on Perioperative Anxiety and Pain in Pediatric Orthopedic Patients: A Randomized Controlled Trial.

PURPOSE: There are currently no pediatric studies examining the effects of deep breathing on perioperative pain and anxiety. This study sought to determine the effect of short-term deep breathing exercises on perioperative anxiety and pain in pediatric patients and their parents. DESIGN: A randomized controlled trial was conducted in the Department of Orthopaedic Surgery where pediatric patients about to undergo surgery were allocated to a control group or a deep breathing group. In the intervention group, patients and their main guardian were guided to practice 10 minutes of deep breathing exercises twice a day for 3 to 4 days prior to surgery. Perioperative anxiety and pain were measured for both the children and parents as outcome indicators. METHODS: Perioperative anxiety was measured using the modified Yale Preoperative Anxiety Scale-Short Form (mYPAS-SF) and state anxiety was measured using the State-Trait Anxiety Inventory (STAI). Patients reported their pain levels daily using the Wong-Baker FACES Pain Rating Scale. The following cutoffs were determined as high levels of anxiety: STAI (adult) > 44, STAI (child) > 36, and mYPAS-SF ≥ 30. FINDINGS: No significant differences were found in the STAI, mYPAS-SF, and Wong-Baker FACES Pain Rating Scale scores of the patients between the intervention and control group. Overall statistics showed that parents had significantly higher postoperative state anxiety levels toward female children (44.93 ± 9.01) compared to male children (40.18 ± 9.89). Preoperative and postoperative parental state anxiety levels were correlated with the child's postoperative anxiety. Furthermore, children's postoperative state anxiety was slightly correlated with postoperative pain. CONCLUSIONS: Short-term use of our deep breathing exercises was ineffective in reducing incidences of perioperative pain and anxiety in pediatric orthopedic patients. A longer period of deep breathing administration may be required for the intervention to be effective. Parental anxiety may have an effect on anxiety levels in children, and postoperative parental anxiety may be affected by the gender of the child.

Highly active and regioselective hydroaminomethylation of olefins catalyzed by Rh/sulfoxantphos with ZSM-5.

Rh-catalyzed hydroaminomethylation has been developed with acid sulfoxantphos and ZSM-5. Linear amines were obtained in good yields (71-95%) with high l/b ratios (up to 132.4) and excellent TON values (up to 23 760). The ZSM-5 and SO3H group of ligands improved the performances of hydroformylation and reductive amination.

Enhanced identification and localization of metabolites in Scutellariae Radix using ion mobility enabled MALDI-Q-TOF/MS imaging.

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