Public Relation Practices in Polytechnic Libraries for Effective Service Delivery in North-Central,Nigeria

This study investigated public relations practices for effective service delivery in polytechnic libraries in North-Central,Nigeria.The study was guided by two research questions.The descriptive survey research design was adopted for this study.The population of the study was 107 library staff consisting of both federal and state polytechnic libraries in North-Central,Nigeria.There was no sampling as all the population of the study was used as sample.Two sets of instruments were used to collect data for the study:questionnaire for library staff and interview guide for the polytechnic librarians.The instruments were subjected to face validation by two experts.Quantitative data were analyzed using descriptive and inferential statistics while the qualitative data were transcribed,coded,and analyzed through document analysis as confirmatory to the quantitative data collected.The formulated hypotheses were tested using t-test.The findings revealed that public relations practices used by librarians were attending to users’enquiries on the public information desks and providing suggestion boxes to collect users’opinions,etc.(X=3.20,Sd=0.77;X=3.10,Sd=0.73);Projectors and bulletin boards were the facilities employed in public relations practices(X=3.21,Sd=0.86;X=3.18,Sd=0.69).Based on the findings,it was recommended that,the library management should create awareness on the public relations practices used for effective service delivery through such fora as workshop,orientation,and seminar to educate library users on the relevance of public relations;also librarians should use every possible avenue to be abreast with state-of-the-art facilities that can be employed in public relations practices in polytechnic libraries for effective service delivery,among others.

Effects of Chirality on Gene Delivery Efficiency of Polylysine

Chirality is a key factor in the biological activity of many biomolecules. Poly（L-lysine）（PLL）, a polypeptide synthesized from L-lysine, is one of the mostly used cationic polymers for gene delivery. The effect of chirality of polylysine（PL） on its gene delivery remains unknown. Herein, we prepared three polylysines（PLs） with the similar molecular weight but different backbone chiralities including poly（L-lysine）（PLL）, poly（D-lysine）（PDL） and poly（DL-lysine）（PDLL）. The side chains of each PL were modified with propylene oxide（PO） of different chiralities including（R）PO,（S）PO and（R,S）PO. These PL-POs with distinct chirality in main and side chains could condense p DNA into polyplexes. The polyplexes had approximately the same size, zeta potential and binding ability, but showed distinct gene transfection efficiency. We found that the PLs of L-configuration in the main chain had higher transfection efficiency than that of D or DL configuration due to their faster cellular uptake, while the side chain chirality had no effect on transfection efficiency.

Anti-tumor effects of combined doxorubicin and siRNA for pulmonary delivery

Direct administration of drugs and genes to the lungs by pulmonary delivery offers a potential effective therapy for lung cancers.In this study,combined doxorubicin（DOX） and Bcl2 siRNA was employed for cancer therapy using polyethylenimine（PEI） as the carrier of Bcl2 siRNA.Most of the DOX and siRNA possessed high cellular uptake efficiency in B16F10 cells,which was proved by FCM and CLSM analysis.Real-time PCR showed that PEI/Bcl2 siRNA exhibited high gene silencing efficiency with 70%Bcl2 mRNA being knocked down.The combination of DOX and siRNA could enhance the cell proliferation inhibition and the cell apoptosis against B16F10 cells compared to free DOX or PEI/Bcl2 siRNA.Furthermore,the biodistribution of DOX and siRNA via pulmonary administration was studied in mice with B16F10 metastatic lung cancer.The results showed that most of the DOX and siRNA were accumulated in lungs and lasted at least for 3 days,which suggested that combined DOX and siRNA by pulmonary administration may have high anti-tumor effects for metastatic lung cancer treatment in vivo.

CRISPR-Cas9 gene editing strengthens cuproptosis/chemodynamic/ferroptosis synergistic cancer therapy

Copper-based nanomaterials demonstrate promising potential in cancer therapy.Cu^(+) efficiently triggers a Fenton-like reaction and further consumes the high level of glutathione,initiating chemical dynamic therapy(CDT)and ferroptosis.Cuproptosis,a newly identified cell death modality that represents a great prospect in cancer therapy,is activated.However,active homeostatic systems rigorously keep copper levels within cells exceptionally low,which hinders the application of cooper nanomaterials-based therapy.Herein,a novel strategy of CRISPR-Cas9 RNP nanocarrier to deliver cuprous ions and suppress the expression of copper transporter protein ATP7A for maintaining a high level of copper in cytoplasmic fluid is developed.The Cu_(2)O and organosilica shell would degrade under the high level of glutathione and weak acidic environment,further releasing RNP and Cu^(+).The liberated Cut triggered a Fenton-like reaction for CDT and partially transformed to Cu^(2+),consuming intracellular GSH and initiating cuproptosis and ferroptosis efficiently.Meanwhile,the release of RNP effectively reduced the expression of copper transporter ATP7A,subsequently increasing the accumulation of cooper and enhancing the efficacy of CDT,cuproptosis,and ferroptosis.Such tumor microenvironment responsive multimodal nanoplatform opens an ingenious avenue for colorectal cancer therapy based on gene editing enhanced synergistic cuproptosis/CDT/ferroptosis.

Redox-responsive polymer prodrug/AgNPs hybrid nanoparticles for drug delivery

A drug carrier system of the hybrid nanoparticles based on the redox-responsive P[（2-（（2-（（camptothecin）-oxy）ethyl）disulfanyl）ethylmethacrylate）-co-（2-（D-galactose）methylmethacryl-ate）]（P（MACPTS-co-MAGP）） and AgNPs is developed to deliver the anti-cancer drug camptothecin（CPT） and monitor the drug release by the recovery of the fluorescence of CPT. CPT is linked to the polymer sidechains via a redox-responsive disulfide bond, attaching on the surface of AgNPs and leading to the quenching of CPT fluorescence（ ＂off＂ state） due to the nanoparticle surface energy transfer（NSET） effect.Upon the exposure to glutathione（GSH）, the disulfide bond is cleaved to release CPT, resulting in the recovery of the fluorescence of CPT（＂on＂ state）. The system offers a platform to track the CPT delivery and releasing in real time