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This work examines the antibacterial and anticandidal activities of zinc oxide nanoparticles (ZNPs) synthesized by high-speed ball milling (HSBM), for short milling times: 0.5, 1, 1.5, and 2 h. First, ZNPs have been characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, and the Zetasizer analyzer. The HSBM results in semispherical ZNPs with some local agglomeration. We found that nanoparticles decrease in size continuously with milling time until they reach about 84% of their original size after only two hours; at 1000 rpm, HSBM reduces ZNP's average size by 6 nm/min. As particle size decreases, the X-ray diffracted patterns become broader and less intense while confirming that no phase transformation has occurred, proving HSBM's effectiveness in synthesizing nanoparticles on a large scale within a short period of time. According to FT-IR analysis, as material sizes change, the polarization charge of the ZNP surface changes as well, creating discrepancies in vibrational frequency, as demonstrated by the shifting of the IR spectra in the 300-600 cm-1 frequency band. Raman responses have also been proven to depend on the particle size. Using the Agar well diffusion method, eleven microorganisms have been tested for the antimicrobial activity of ZNPs. Among the six Gram-negative tested bacteria, S. sonnei showed the largest inhibition zone of about 11.3 ± 0.6 mm with ZNPs measuring 148 nm in size (milled for 2 h), followed by E. coli ATCC 25922. Accordingly, S. aureus was the most susceptible Gram-positive bacteria, with inhibition zone size gradually increasing from 11.8 ± 0.3 mm to 13.5 ± 0.5 mm with decreasing nanoparticle size from 767 to 148 nm, while S. aureus ATCC 25923 was resistant to both milled and unmilled samples. Similar results were seen with candida, all milled ZNPs inhibited C. albicans, followed by C. tropicalis, whereas C. knisei was resistant to all ZNP sizes. In light of microorganism-ZNP interaction mechanisms, the obtained results have been discussed in depth.
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INTRODUCTION: Dyslipidemia is the most important modifiable risk factor that leads to cardiovascular diseases. The screening for dyslipidemia in Palestine is not established in primary health care centers for healthy people. Our study aims to determine the prevalence of dyslipidemia among healthy undiagnosed adult men in Palestine in order to assess the need for screening and preventive programs for dyslipidemia. MATERIALS AND METHODS: A cross-sectional observational study was carried out in 10 secondary schools at Nablus municipality (Palestine) from August 2017 to February 2018. The study included 140 teachers based on sample calculations. The age of participants ranged between 24 and 60 years. A questionnaire was used to collect demographic data about the lifestyle, past medical, and family histories. Serum lipid profile, and fasting blood glucose levels for each participant were measured. Lipoprotein levels were categorized based on the adult treatment panel III criteria. RESULTS: The overall prevalence of dyslipidemia among Palestinian men was 66.4%. The most prevalent type of dyslipidemia was hypo HDL (X < 40 mg/dl, 59.3%), followed by hypertriglyceridemia (X ≥ 200 mg/dl, 20%). The prevalence of hyper LDL (X ≥ 160 mg/dl), hypercholesterolemia (X ≥ 240 mg/dl) was 8.5%, and 3.6%, respectively. About 15% of participants had glucose intolerance, and 4.3% had hyperglycemia (undiagnosed). Those with glucose intolerance, 13 (9.2%) have hypo HDL, while 9 (6.42%) have hypertriglyceridemia. On the other hand, out of hyperglycemic patients: 5 (3.5%) had hypo HDL, and 1 (0.7%) had hypertriglyceridemia. CONCLUSION: Around two-thirds of undiagnosed participants had at least one lipid abnormality. None of them were aware of having dyslipidemia. The prevalence of undiagnosed dyslipidemia was higher than the prevalence of undiagnosed glucose intolerance, and diabetes. This suggests that dyslipidemia plays a major role in developing diabetes. Hence, profound efforts should be done to manage and treat those with dyslipidemia, in order to prevent progression to type II diabetes mellitus.
