Activity of zinc oxide and zinc borate nanoparticles against resistant bacteria in an experimental lung cancer model.

BACKGROUND: Recent research indicates a prevalence of typical lung infections, such as pneumonia, in lung cancer patients. Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii stand out as antibiotic-resistant pathogens. Given this, there is a growing interest in alternative therapeutic avenues. Boron and zinc derivatives exhibit antimicrobial, antiviral, and antifungal properties. OBJECTIVES: This research aimed to establish the effectiveness of ZnO and ZB NPs in combating bacterial infections in lung cancer cell lines. METHODS: Initially, this study determined the minimal inhibitory concentration (MIC) and fractional inhibitory concentration (FIC) of zinc oxide nanoparticles (ZnO NPs) and zinc borate (ZB) on chosen benchmark strains. Subsequent steps involved gauging treatment success through a lung cancer-bacteria combined culture and immunohistochemical analysis. RESULTS: The inhibitory impact of ZnO NPs on bacteria was charted as follows: 0.97 µg/mL for K. pneumoniae 700603, 1.95 µg/mL for P. aeruginosa 27853, and 7.81 µg/mL for Acinetobacter baumannii 19,606. In comparison, the antibacterial influence of zinc borate was measured as 7.81 µg/mL for Klebsiella pneumoniae 700603 and 500 µg/mL for both P. aeruginosa 27853 and A.baumannii 19606. After 24 h, the cytotoxicity of ZnO NPs and ZB was analyzed using the MTT technique. The lowest cell viability was marked in the 500 µg/mL ZB NPs group, with a viability rate of 48.83% (P < 0.001). However, marked deviations appeared at ZB concentrations of 61.5 µg/mL (P < 0.05) and ZnO NPs at 125 µg/mL. CONCLUSION: A synergistic microbial inhibitory effect was observed when ZnO NP and ZB were combined against the bacteria under investigation.

Cancer Marker Immunosensing through Surface-Enhanced Photoluminescence on Nanostructured Silver Substrates.

Nanostructured noble metal surfaces enhance the photoluminescence emitted by fluorescent molecules, permitting the development of highly sensitive fluorescence immunoassays. To this end, surfaces with silicon nanowires decorated with silver nanoparticles in the form of dendrites or aggregates were evaluated as substrates for the immunochemical detection of two ovarian cancer indicators, carbohydrate antigen 125 (CA125) and human epididymis protein 4 (HE4). The substrates were prepared by metal-enhanced chemical etching of silicon wafers to create, in one step, silicon nanowires and silver nanoparticles on top of them. For both analytes, non-competitive immunoassays were developed using pairs of highly specific monoclonal antibodies, one for analyte capture on the substrate and the other for detection. In order to facilitate the identification of the immunocomplexes through a reaction with streptavidin labeled with Rhodamine Red-X, the detection antibodies were biotinylated. An in-house-developed optical set-up was used for photoluminescence signal measurements after assay completion. The detection limits achieved were 2.5 U/mL and 3.12 pM for CA125 and HE4, respectively, with linear dynamic ranges extending up to 500 U/mL for CA125 and up to 500 pM for HE4, covering the concentration ranges of both healthy and ovarian cancer patients. Thus, the proposed method could be implemented for the early diagnosis and/or prognosis and monitoring of ovarian cancer.

Health risk behaviors among high school and university adolescent students.

Tobacco, alcohol and drug abuse constitute a public health concern. Data regarding health risk behaviors among Greek youth are scarce. The aim of the present study was to investigate health risk behaviors of a large adolescent sample (730 adolescents, 294 males and 436 females), residing in different areas of Greece, trace perceived side effects and associate the findings with the adopted lifestyle. High school students and University newcomers, aged 14-21 years (17.8±4.5 years), self-reported health risk behaviors via an anonymous, closed-type, validated questionnaire. Simultaneous adoption of unhealthy habits, such as smoking and drug abuse, were not independent (χ2=38.668, P=0.01). Age was the most significant factor in the adoption of unhealthy behaviors; smoking (χ2=27.220, P=0.01), misuse of cannabis and recreational drugs (χ2=9.874, P=0.05) and combining alcohol and smoking with entertainment (χ2=8.708, P=0.05; χ2=317.309, P=0.05, respectively) were adopted more by the elder (18-20 years) than the younger (15-18 years) teenagers. Males were more prone to abuse of cannabis (χ2=8.844, P=0.01), whereas females combined drinking and smoking with loud music during entertainment (χ2=6.618, P=0.05). The majority (64%) reported driving after drinking alcohol and intense entertainment, especially in urban areas. Almost half of smokers (53.1%) and drug users (46.3%) first encountered smoking or drugs from friends. Educational institutions and entertainment venues were the main places of initiation of smoking (26%) or drug use (35.2%), respectively. Adolescents from touristic regions were more prone to smoking (33.9%, P=0.01) and drug abuse (53.7%, P=0.01). The lower the frequency of exercise, the higher the consumption of psychoactive substances (P=0.022). Youth engaging in unhealthy habits were also willing to use prohibited doping substances (56%, P=0.043). Health problems were the main reason to consider changing habits (72%). In conclusion, health risk behaviors were multifactorial and tended to cluster. Thus, preventive youth strategies should target negative peer influences, especially during late adolescence.